Copper(II) ion

evidence_span

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experimental_model

Copper and iron exposure with transcription-factor knockdown

exposure

CuCl2 or FeCl2 exposure; NFE2L2 or ATOX1 knockdown

limitations

One cancer-cell model. Expression changes do not prove increased glutathione synthesis, tumor progression, or a clinical nutrient interaction.

nutrient_topic

Copper research collection; topical membership is not evidence of a direct dietary effect. · Copper

organism

Human MDA-MB-231 breast cancer cells

plain_language

A stress-response regulator moved to the cell’s DNA-containing compartment.

primary_references

[copper-p40944334] Copper induces cystine/glutamate antiporter SLC7A11 through the activation of Nrf2 and Atox1 pathways. (2025). https://pubmed.ncbi.nlm.nih.gov/40944334/ DOI: 10.1080/10715762.2025.2560847

tissue_or_cell_type

Cellular amino-acid transport machinery

Copper: transport, cuproenzymes, deficiency, excess and nutrient interactions (2026-09-17) · lines 1287–1298

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Copper and iron exposure with transcription-factor knockdown · source_derived_draft · unverified_draft

### copper-cu-nrf2 CuCl2 exposure promoted NRF2 nuclear translocation in the tested cancer cells. Condition category: normal nutrient_topic: Copper research collection; topical membership is not evidence of a direct dietary effect. plain_language: A stress-response regulator moved to the cell’s DNA-containing compartment. organism: Human MDA-MB-231 breast cancer cells tissue_or_cell_type: Cellular amino-acid transport machinery experimental_model: Copper and iron exposure with transcription-factor knockdown limitations: One cancer-cell model. Expression changes do not prove increased glutathione synthesis, tumor progression, or a clinical nutrient interaction. exposure: CuCl2 or FeCl2 exposure; NFE2L2 or ATOX1 knockdown evidence_span: {"source_cache": "artifacts/copper-research/40944334.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6df1716e8998546d22a1d96116e1bc35b1f7e24c94868ec5e441ada6a2be3e89", "start_char": 0, "end_char": 1634, "text_sha256": "6df1716e8998546d22a1d96116e1bc35b1f7e24c94868ec5e441ada6a2be3e89"} [copper-p40944334] Copper induces cystine/glutamate antiporter SLC7A11 through the activation of Nrf2 and Atox1 pathways. (2025). https://pubmed.ncbi.nlm.nih.gov/40944334/ DOI: 10.1080/10715762.2025.2560847

evidence_span

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experimental_model

Copper and iron exposure with transcription-factor knockdown

exposure

CuCl2 or FeCl2 exposure; NFE2L2 or ATOX1 knockdown

limitations

One cancer-cell model. Expression changes do not prove increased glutathione synthesis, tumor progression, or a clinical nutrient interaction.

nutrient_topic

Copper research collection; topical membership is not evidence of a direct dietary effect. · Copper

organism

Human MDA-MB-231 breast cancer cells

plain_language

Copper exposure changed part of the cystine-entry system in these cells.

primary_references

[copper-p40944334] Copper induces cystine/glutamate antiporter SLC7A11 through the activation of Nrf2 and Atox1 pathways. (2025). https://pubmed.ncbi.nlm.nih.gov/40944334/ DOI: 10.1080/10715762.2025.2560847

tissue_or_cell_type

Cellular amino-acid transport machinery

Copper: transport, cuproenzymes, deficiency, excess and nutrient interactions (2026-09-17) · lines 1274–1285

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Copper and iron exposure with transcription-factor knockdown · source_derived_draft · unverified_draft

### copper-cu-slc7a11 CuCl2 treatment induced SLC7A11 expression in human MDA-MB-231 cells. Condition category: normal nutrient_topic: Copper research collection; topical membership is not evidence of a direct dietary effect. plain_language: Copper exposure changed part of the cystine-entry system in these cells. organism: Human MDA-MB-231 breast cancer cells tissue_or_cell_type: Cellular amino-acid transport machinery experimental_model: Copper and iron exposure with transcription-factor knockdown limitations: One cancer-cell model. Expression changes do not prove increased glutathione synthesis, tumor progression, or a clinical nutrient interaction. exposure: CuCl2 or FeCl2 exposure; NFE2L2 or ATOX1 knockdown evidence_span: {"source_cache": "artifacts/copper-research/40944334.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6df1716e8998546d22a1d96116e1bc35b1f7e24c94868ec5e441ada6a2be3e89", "start_char": 0, "end_char": 1634, "text_sha256": "6df1716e8998546d22a1d96116e1bc35b1f7e24c94868ec5e441ada6a2be3e89"} [copper-p40944334] Copper induces cystine/glutamate antiporter SLC7A11 through the activation of Nrf2 and Atox1 pathways. (2025). https://pubmed.ncbi.nlm.nih.gov/40944334/ DOI: 10.1080/10715762.2025.2560847

evidence_access

Primary abstract

experimental_model

Native rat-liver carrier; recombinant cysteine mutants supported involvement of C136 and C155.

limitations

Free copper in an assay is not dietary copper exposure; no clinical deficiency or toxicity threshold follows.

nutrient_topic

L-Carnitine collection; isomer, preparation, species, exposure and manipulation remain explicit. · L-Carnitine

plain_language

Metal exposure can interfere with the carrier in a controlled assay.

primary_references

Effect of Copper on the Mitochondrial Carnitine/Acylcarnitine Carrier Via Interaction with Cys136 and Cys155. Possible Implications in Pathophysiology. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32070004/ · DOI 10.3390/molecules25040820

L-Carnitine: synthesis, acyl-group transport, fuel selection and nutrient interactions (2026-09-19) · lines 138–144

AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Native rat-liver carrier; recombinant cysteine mutants supported involvement of C136 and C155. · source_derived_draft · unverified_draft

## l-carnitine-copper-carrier Metal exposure can interfere with the carrier in a controlled assay. Copper inhibited rat-liver CACT carnitine exchange in proteoliposomes, with a native-protein IC50 of 1.6 micromolar. Model: Native rat-liver carrier; recombinant cysteine mutants supported involvement of C136 and C155. Limitations: Free copper in an assay is not dietary copper exposure; no clinical deficiency or toxicity threshold follows. Evidence access: Primary abstract Effect of Copper on the Mitochondrial Carnitine/Acylcarnitine Carrier Via Interaction with Cys136 and Cys155. Possible Implications in Pathophysiology. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32070004/ · DOI 10.3390/molecules25040820

availability_state

nutrient_deficiency Imported condition classification; unverified.

experimental_model

Chicks receiving diets differing in copper; tendon enzyme assays.

limitations

Copper manipulation in chicks, not evidence of dietary lysine deficiency or a human copper/lysine dose recommendation.

organism

Chicken

plain_language

Insufficient copper can limit a lysine-processing enzyme even when its substrate is present.

primary_references

[lox-copper-1999] Activation of chick tendon lysyl oxidase in response to dietary copper (1999). https://pubmed.ncbi.nlm.nih.gov/10573541/

tissue_or_cell_type

Tendon

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

L-Lysine: mechanism-first literature curation (2026-09-17) · lines 497–505

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Chicks receiving diets differing in copper; tendon enzyme assays. · source_derived_draft · unverified_draft

### copper-insufficiency-lox Dietary copper availability altered tendon lysyl-oxidase activation in the chick experiments. Plain language: Insufficient copper can limit a lysine-processing enzyme even when its substrate is present. Condition category: nutrient_deficiency organism: Chicken tissue_or_cell_type: Tendon experimental_model: Chicks receiving diets differing in copper; tendon enzyme assays. limitations: Copper manipulation in chicks, not evidence of dietary lysine deficiency or a human copper/lysine dose recommendation. [lox-copper-1999] Activation of chick tendon lysyl oxidase in response to dietary copper (1999). https://pubmed.ncbi.nlm.nih.gov/10573541/

cross_nutrient

Vitamin C chemistry in collagen, modified-lysine/carnitine metabolism or copper-dependent peptide/catecholamine processing.

experimental_model

Rat pituitary and bovine intermediate-pituitary secretory-granule preparations

exposure

Synthetic D-Tyr-Val-Gly amidation with varied ascorbate, oxygen and divalent-metal chelators/copper.

limitations

Study included rat and bovine preparations; this cofactor observation is scoped to those preparations rather than a human nutritional copper trial.

nutrient_topic

Vitamin C research collection; topical membership is not evidence of a direct dietary effect. · Vitamin C

organism

Rattus norvegicus; Bos taurus

plain_language

Vitamin C and copper participate together, and removing available metal stops this peptide-processing assay.

primary_references

[pam1983] Identification in pituitary tissue of a peptide alpha-amidation activity that acts on glycine-extended peptides and requires molecular oxygen, copper, and ascorbic acid. (1983). https://pubmed.ncbi.nlm.nih.gov/6576381/ DOI: 10.1073/pnas.80.16.5144

tissue_or_cell_type

Pituitary secretory granules

Vitamin C: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 872–883

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Rat pituitary and bovine intermediate-pituitary secretory-granule preparations · source_derived_draft · unverified_draft

### vc-enzyme-amidation-copper-recovery Pituitary peptide-amidating activity inhibited by divalent-metal chelators was restored above control by copper addition; the assayed reaction also required molecular oxygen. Condition category: normal nutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect. plain_language: Vitamin C and copper participate together, and removing available metal stops this peptide-processing assay. organism: Rattus norvegicus; Bos taurus tissue_or_cell_type: Pituitary secretory granules experimental_model: Rat pituitary and bovine intermediate-pituitary secretory-granule preparations limitations: Study included rat and bovine preparations; this cofactor observation is scoped to those preparations rather than a human nutritional copper trial. cross_nutrient: Vitamin C chemistry in collagen, modified-lysine/carnitine metabolism or copper-dependent peptide/catecholamine processing. exposure: Synthetic D-Tyr-Val-Gly amidation with varied ascorbate, oxygen and divalent-metal chelators/copper. [pam1983] Identification in pituitary tissue of a peptide alpha-amidation activity that acts on glycine-extended peptides and requires molecular oxygen, copper, and ascorbic acid. (1983). https://pubmed.ncbi.nlm.nih.gov/6576381/ DOI: 10.1073/pnas.80.16.5144

evidence_span

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experimental_model

Mouse Steap expression constructs and metal-reduction assays

exposure

Transient expression of Steap2, Steap3 or Steap4

limitations

Protein species verified in primary Methods (PMC1785011). Overexpression does not establish the dominant intestinal reductase in humans; relative activity can reflect localization and abundance.

nutrient_topic

Copper research collection; topical membership is not evidence of a direct dietary effect. · Copper

organism

Mouse proteins expressed in human HEK293T cells

plain_language

This enzyme prepares copper in a chemical form compatible with uptake.

primary_references

[copper-p16609065] The Steap proteins are metalloreductases. (2006). https://pubmed.ncbi.nlm.nih.gov/16609065/ DOI: 10.1182/blood-2006-02-003681

tissue_or_cell_type

Cell surface and endosomal compartments

Copper: transport, cuproenzymes, deficiency, excess and nutrient interactions (2026-09-17) · lines 273–284

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Mouse Steap expression constructs and metal-reduction assays · source_derived_draft · unverified_draft

### copper-steap2-reduces-copper Expressed mouse Steap2 reduced Cu(II) to Cu(I) and increased cellular copper uptake in the tested human cell system. Condition category: normal nutrient_topic: Copper research collection; topical membership is not evidence of a direct dietary effect. plain_language: This enzyme prepares copper in a chemical form compatible with uptake. organism: Mouse proteins expressed in human HEK293T cells tissue_or_cell_type: Cell surface and endosomal compartments experimental_model: Mouse Steap expression constructs and metal-reduction assays limitations: Protein species verified in primary Methods (PMC1785011). Overexpression does not establish the dominant intestinal reductase in humans; relative activity can reflect localization and abundance. exposure: Transient expression of Steap2, Steap3 or Steap4 evidence_span: {"source_cache": "artifacts/copper-research/16609065.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "d0f42a3f30c22ba4235d82f21ba165c78b6c519a6218f487411fb2247ecc0d9f", "start_char": 0, "end_char": 827, "text_sha256": "d0f42a3f30c22ba4235d82f21ba165c78b6c519a6218f487411fb2247ecc0d9f"} [copper-p16609065] The Steap proteins are metalloreductases. (2006). https://pubmed.ncbi.nlm.nih.gov/16609065/ DOI: 10.1182/blood-2006-02-003681

evidence_span

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experimental_model

Mouse Steap expression constructs and metal-reduction assays

exposure

Transient expression of Steap2, Steap3 or Steap4

limitations

Protein species verified in primary Methods (PMC1785011). Overexpression does not establish the dominant intestinal reductase in humans; relative activity can reflect localization and abundance.

nutrient_topic

Copper research collection; topical membership is not evidence of a direct dietary effect. · Copper

organism

Mouse proteins expressed in human HEK293T cells

plain_language

This enzyme prepares copper in a chemical form compatible with uptake.

primary_references

[copper-p16609065] The Steap proteins are metalloreductases. (2006). https://pubmed.ncbi.nlm.nih.gov/16609065/ DOI: 10.1182/blood-2006-02-003681

tissue_or_cell_type

Cell surface and endosomal compartments

Copper: transport, cuproenzymes, deficiency, excess and nutrient interactions (2026-09-17) · lines 286–297

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Mouse Steap expression constructs and metal-reduction assays · source_derived_draft · unverified_draft

### copper-steap3-reduces-copper Expressed mouse Steap3 reduced Cu(II) to Cu(I) and increased cellular copper uptake in the tested human cell system. Condition category: normal nutrient_topic: Copper research collection; topical membership is not evidence of a direct dietary effect. plain_language: This enzyme prepares copper in a chemical form compatible with uptake. organism: Mouse proteins expressed in human HEK293T cells tissue_or_cell_type: Cell surface and endosomal compartments experimental_model: Mouse Steap expression constructs and metal-reduction assays limitations: Protein species verified in primary Methods (PMC1785011). Overexpression does not establish the dominant intestinal reductase in humans; relative activity can reflect localization and abundance. exposure: Transient expression of Steap2, Steap3 or Steap4 evidence_span: {"source_cache": "artifacts/copper-research/16609065.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "d0f42a3f30c22ba4235d82f21ba165c78b6c519a6218f487411fb2247ecc0d9f", "start_char": 0, "end_char": 827, "text_sha256": "d0f42a3f30c22ba4235d82f21ba165c78b6c519a6218f487411fb2247ecc0d9f"} [copper-p16609065] The Steap proteins are metalloreductases. (2006). https://pubmed.ncbi.nlm.nih.gov/16609065/ DOI: 10.1182/blood-2006-02-003681

evidence_span

{"source_cache": "artifacts/copper-research/16609065.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "d0f42a3f30c22ba4235d82f21ba165c78b6c519a6218f487411fb2247ecc0d9f", "start_char": 0, "end_char": 827, "text_sha256": "d0f42a3f30c22ba4235d82f21ba165c78b6c519a6218f487411fb2247ecc0d9f"}

experimental_model

Mouse Steap expression constructs and metal-reduction assays

exposure

Transient expression of Steap2, Steap3 or Steap4

limitations

Protein species verified in primary Methods (PMC1785011). Overexpression does not establish the dominant intestinal reductase in humans; relative activity can reflect localization and abundance.

nutrient_topic

Copper research collection; topical membership is not evidence of a direct dietary effect. · Copper

organism

Mouse proteins expressed in human HEK293T cells

plain_language

This enzyme prepares copper in a chemical form compatible with uptake.

primary_references

[copper-p16609065] The Steap proteins are metalloreductases. (2006). https://pubmed.ncbi.nlm.nih.gov/16609065/ DOI: 10.1182/blood-2006-02-003681

tissue_or_cell_type

Cell surface and endosomal compartments

Copper: transport, cuproenzymes, deficiency, excess and nutrient interactions (2026-09-17) · lines 299–310

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Mouse Steap expression constructs and metal-reduction assays · source_derived_draft · unverified_draft

### copper-steap4-reduces-copper Expressed mouse Steap4 reduced Cu(II) to Cu(I) and increased cellular copper uptake in the tested human cell system. Condition category: normal nutrient_topic: Copper research collection; topical membership is not evidence of a direct dietary effect. plain_language: This enzyme prepares copper in a chemical form compatible with uptake. organism: Mouse proteins expressed in human HEK293T cells tissue_or_cell_type: Cell surface and endosomal compartments experimental_model: Mouse Steap expression constructs and metal-reduction assays limitations: Protein species verified in primary Methods (PMC1785011). Overexpression does not establish the dominant intestinal reductase in humans; relative activity can reflect localization and abundance. exposure: Transient expression of Steap2, Steap3 or Steap4 evidence_span: {"source_cache": "artifacts/copper-research/16609065.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "d0f42a3f30c22ba4235d82f21ba165c78b6c519a6218f487411fb2247ecc0d9f", "start_char": 0, "end_char": 827, "text_sha256": "d0f42a3f30c22ba4235d82f21ba165c78b6c519a6218f487411fb2247ecc0d9f"} [copper-p16609065] The Steap proteins are metalloreductases. (2006). https://pubmed.ncbi.nlm.nih.gov/16609065/ DOI: 10.1182/blood-2006-02-003681

evidence_access

Primary abstract

experimental_model

Cell-free Cu(II) spectroscopy.

limitations

Metal, pH and preparation matter; no human copper-balance measurement.

nutrient_topic

Luteolin collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Luteolin / 3′,4′,5,7-tetrahydroxyflavone

plain_language

Copper need not bind at the same site assigned for iron.

primary_references

The effect of Luteolin on DNA damage mediated by a copper catalyzed Fenton reaction. · 2022 · https://pubmed.ncbi.nlm.nih.gov/34717250/ · DOI 10.1016/j.jinorgbio.2021.111635

Luteolin: metabolism, immune signaling, redox chemistry and cross-nutrient mechanisms (2026-09-19) · lines 316–322

AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Cell-free Cu(II) spectroscopy. · source_derived_draft · unverified_draft

## luteolin-copper-binding Copper need not bind at the same site assigned for iron. Spectroscopy assigned Cu(II) coordination by luteolin to the 5-hydroxyl/4-carbonyl region. Model: Cell-free Cu(II) spectroscopy. Limitations: Metal, pH and preparation matter; no human copper-balance measurement. Evidence access: Primary abstract The effect of Luteolin on DNA damage mediated by a copper catalyzed Fenton reaction. · 2022 · https://pubmed.ncbi.nlm.nih.gov/34717250/ · DOI 10.1016/j.jinorgbio.2021.111635

evidence_span

{"source_cache": "artifacts/ala-research/9680174.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ac15770e92102947345520296b7795e8ff2dca2c345ac76c14b929fbd19739f1", "start_char": 0, "end_char": 2034, "text_sha256": "ac15770e92102947345520296b7795e8ff2dca2c345ac76c14b929fbd19739f1"}

experimental_model

Cell-free human LDL oxidation and electron-spin-resonance assays

exposure

Copper 5 micromolar; DHLA 0–20 micromolar; oxygen and pH varied

limitations

Metal binding, reduction and radical production depend on ratio, oxygen and pH; not evidence for human metal-detoxification efficacy.

nutrient_topic

Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect. · Lipoic acid

organism

Human LDL; cell-free chemistry

plain_language

Whether copper was bound or chemically reduced depended on the relative amounts.

primary_references

[ala-p9680174] Thiol chelation of Cu2+ by dihydrolipoic acid prevents human low density lipoprotein peroxidation. (1998). https://pubmed.ncbi.nlm.nih.gov/9680174/ DOI: 10.1016/s0891-5849(98)00048-3

tissue_or_cell_type

LDL and copper/DHLA solutions

Alpha-lipoic acid: cofactor assembly, redox signaling and nutrient interactions (2026-09-17) · lines 1053–1064

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cell-free human LDL oxidation and electron-spin-resonance assays · source_derived_draft · unverified_draft

### ala-dhla-copper-ratio DHLA favored copper reduction when copper was in excess and chelation when DHLA was in excess. Condition category: normal nutrient_topic: Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect. plain_language: Whether copper was bound or chemically reduced depended on the relative amounts. organism: Human LDL; cell-free chemistry tissue_or_cell_type: LDL and copper/DHLA solutions experimental_model: Cell-free human LDL oxidation and electron-spin-resonance assays limitations: Metal binding, reduction and radical production depend on ratio, oxygen and pH; not evidence for human metal-detoxification efficacy. exposure: Copper 5 micromolar; DHLA 0–20 micromolar; oxygen and pH varied evidence_span: {"source_cache": "artifacts/ala-research/9680174.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ac15770e92102947345520296b7795e8ff2dca2c345ac76c14b929fbd19739f1", "start_char": 0, "end_char": 2034, "text_sha256": "ac15770e92102947345520296b7795e8ff2dca2c345ac76c14b929fbd19739f1"} [ala-p9680174] Thiol chelation of Cu2+ by dihydrolipoic acid prevents human low density lipoprotein peroxidation. (1998). https://pubmed.ncbi.nlm.nih.gov/9680174/ DOI: 10.1016/s0891-5849(98)00048-3

evidence_access

Primary abstract

experimental_model

Single oral radiocopper dose to 10-12-day-old rats; 0.93 mg Cu/L with 10 mg fulvic/L; chemical fractionation.

limitations

Binding is not evidence of improved systemic delivery.

nutrient_topic

Fulvic acid collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · Fulvic acid (heterogeneous humic fraction)

plain_language

Copper can bind components of the mixture.

primary_references

Intestinal absorption of copper from drinking water containing fulvic acids and an infant formula mixture studied in a suckling rat model. · 1999 · https://pubmed.ncbi.nlm.nih.gov/10406087/ · DOI 10.1023/a:1009233802104

Fulvic acid: mixture identity, mineral chemistry, signaling and cross-nutrient mechanisms (2026-09-19) · lines 76–82

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Single oral radiocopper dose to 10-12-day-old rats; 0.93 mg Cu/L with 10 mg fulvic/L; chemical fractionation. · source_derived_draft · unverified_draft

## fulvic-acid-copper-binding Copper can bind components of the mixture. Dialysis and centrifugation showed copper association with the tested fulvic mixture. Model: Single oral radiocopper dose to 10-12-day-old rats; 0.93 mg Cu/L with 10 mg fulvic/L; chemical fractionation. Limitations: Binding is not evidence of improved systemic delivery. Evidence access: Primary abstract Intestinal absorption of copper from drinking water containing fulvic acids and an infant formula mixture studied in a suckling rat model. · 1999 · https://pubmed.ncbi.nlm.nih.gov/10406087/ · DOI 10.1023/a:1009233802104

evidence_span

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experimental_model

Computational and binding comparison of metformin and propanediimidamide with copper

exposure

Copper(I) and copper(II) binding energies, pKa and hydrophilicity

limitations

A chemistry study proposing a pro-oxidant role. It is explicitly a hypothesis about mitochondrial activity, not a cellular measurement.

nutrient_topic

Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. · Metformin

organism

Chemical and computational

plain_language

The drug grabs copper tightly enough that it could pull it off proteins and oxidise it.

primary_references

[metformin-p24433134] Biomolecular mode of action of metformin in relation to its copper binding properties. (2014). https://pubmed.ncbi.nlm.nih.gov/24433134/ DOI: 10.1021/bi401444n

tissue_or_cell_type

Molecular interaction

Metformin: transport, molecular targets, gut mechanisms and nutrient interactions (2026-09-19) · lines 1373–1384

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Computational and binding comparison of metformin and propanediimidamide with copper · source_derived_draft · unverified_draft

### metformin-copper-binding-chemistry Metformin can occur as an anion in aqueous medium at moderate pH and forms much stronger complexes with Cu(II) ions than the comparator propanediimidamide, suggesting that biguanides may induce oxidation of Cu(I) ions extracted from proteins. Condition category: normal nutrient_topic: Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. plain_language: The drug grabs copper tightly enough that it could pull it off proteins and oxidise it. organism: Chemical and computational tissue_or_cell_type: Molecular interaction experimental_model: Computational and binding comparison of metformin and propanediimidamide with copper limitations: A chemistry study proposing a pro-oxidant role. It is explicitly a hypothesis about mitochondrial activity, not a cellular measurement. exposure: Copper(I) and copper(II) binding energies, pKa and hydrophilicity evidence_span: {"source_cache": "artifacts/metformin-research/24433134.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a6dda36e30a49ba48e8200b6de36f39a8ab80a1bcbda819c03d3442bb8705963", "start_char": 0, "end_char": 1430, "text_sha256": "a6dda36e30a49ba48e8200b6de36f39a8ab80a1bcbda819c03d3442bb8705963"} [metformin-p24433134] Biomolecular mode of action of metformin in relation to its copper binding properties. (2014). https://pubmed.ncbi.nlm.nih.gov/24433134/ DOI: 10.1021/bi401444n

evidence_span

{"source_cache": "artifacts/chlorogenic_acid-research/9089288.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "459e8c9d21cadd0d8e0cd76d596dd8b6deb9c373fb7d4ee9efb8e8f507ed03ff", "start_char": 0, "end_char": 1419, "text_sha256": "459e8c9d21cadd0d8e0cd76d596dd8b6deb9c373fb7d4ee9efb8e8f507ed03ff"}

experimental_model

Isolated human LDL oxidation with copper challenge

exposure

CGA 0.5 micromolar at initiation; 0.1 micromolar or more during propagation

limitations

Reaction phase and concentration determine direction. This does not show that dietary CGA plus copper produces vascular harm. More detailed caffeic-acid timing and concentration findings must not be transferred to CGA.

nutrient_topic

Chlorogenic acid research collection; topical membership is not evidence of a direct dietary effect. · Chlorogenic acid / 5-O-caffeoylquinic acid

organism

Human LDL outside the body

plain_language

The early reaction stage showed antioxidant behavior.

primary_references

[chlorogenic_acid-p9089288] Prooxidant activity of caffeic acid, dietary non-flavonoid phenolic acid, on Cu2+-induced low density lipoprotein oxidation. (1997). https://pubmed.ncbi.nlm.nih.gov/9089288/ DOI: 10.1016/s0014-5793(97)00185-3

tissue_or_cell_type

LDL oxidation initiation versus propagation

Chlorogenic acid: metabolism, signaling and nutrient connections (2026-09-17) · lines 737–748

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Isolated human LDL oxidation with copper challenge · source_derived_draft · unverified_draft

### chlorogenic_acid-ldl-initiation CGA at 0.5 micromolar inhibited copper-induced LDL oxidation during initiation. Condition category: normal nutrient_topic: Chlorogenic acid research collection; topical membership is not evidence of a direct dietary effect. plain_language: The early reaction stage showed antioxidant behavior. organism: Human LDL outside the body tissue_or_cell_type: LDL oxidation initiation versus propagation experimental_model: Isolated human LDL oxidation with copper challenge limitations: Reaction phase and concentration determine direction. This does not show that dietary CGA plus copper produces vascular harm. More detailed caffeic-acid timing and concentration findings must not be transferred to CGA. exposure: CGA 0.5 micromolar at initiation; 0.1 micromolar or more during propagation evidence_span: {"source_cache": "artifacts/chlorogenic_acid-research/9089288.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "459e8c9d21cadd0d8e0cd76d596dd8b6deb9c373fb7d4ee9efb8e8f507ed03ff", "start_char": 0, "end_char": 1419, "text_sha256": "459e8c9d21cadd0d8e0cd76d596dd8b6deb9c373fb7d4ee9efb8e8f507ed03ff"} [chlorogenic_acid-p9089288] Prooxidant activity of caffeic acid, dietary non-flavonoid phenolic acid, on Cu2+-induced low density lipoprotein oxidation. (1997). https://pubmed.ncbi.nlm.nih.gov/9089288/ DOI: 10.1016/s0014-5793(97)00185-3

evidence_span

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experimental_model

Isolated human LDL oxidation with copper challenge

exposure

CGA 0.5 micromolar at initiation; 0.1 micromolar or more during propagation

limitations

Reaction phase and concentration determine direction. This does not show that dietary CGA plus copper produces vascular harm. More detailed caffeic-acid timing and concentration findings must not be transferred to CGA.

nutrient_topic

Chlorogenic acid research collection; topical membership is not evidence of a direct dietary effect. · Chlorogenic acid / 5-O-caffeoylquinic acid

organism

Human LDL outside the body

plain_language

Once oxidation was underway, the direction differed.

primary_references

[chlorogenic_acid-p9089288] Prooxidant activity of caffeic acid, dietary non-flavonoid phenolic acid, on Cu2+-induced low density lipoprotein oxidation. (1997). https://pubmed.ncbi.nlm.nih.gov/9089288/ DOI: 10.1016/s0014-5793(97)00185-3

tissue_or_cell_type

LDL oxidation initiation versus propagation

Chlorogenic acid: metabolism, signaling and nutrient connections (2026-09-17) · lines 750–761

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Isolated human LDL oxidation with copper challenge · source_derived_draft · unverified_draft

### chlorogenic_acid-ldl-propagation CGA at 0.1 micromolar or more enhanced LDL oxidation during propagation. Condition category: normal nutrient_topic: Chlorogenic acid research collection; topical membership is not evidence of a direct dietary effect. plain_language: Once oxidation was underway, the direction differed. organism: Human LDL outside the body tissue_or_cell_type: LDL oxidation initiation versus propagation experimental_model: Isolated human LDL oxidation with copper challenge limitations: Reaction phase and concentration determine direction. This does not show that dietary CGA plus copper produces vascular harm. More detailed caffeic-acid timing and concentration findings must not be transferred to CGA. exposure: CGA 0.5 micromolar at initiation; 0.1 micromolar or more during propagation evidence_span: {"source_cache": "artifacts/chlorogenic_acid-research/9089288.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "459e8c9d21cadd0d8e0cd76d596dd8b6deb9c373fb7d4ee9efb8e8f507ed03ff", "start_char": 0, "end_char": 1419, "text_sha256": "459e8c9d21cadd0d8e0cd76d596dd8b6deb9c373fb7d4ee9efb8e8f507ed03ff"} [chlorogenic_acid-p9089288] Prooxidant activity of caffeic acid, dietary non-flavonoid phenolic acid, on Cu2+-induced low density lipoprotein oxidation. (1997). https://pubmed.ncbi.nlm.nih.gov/9089288/ DOI: 10.1016/s0014-5793(97)00185-3

availability_state

nutrient_deficiency Imported condition classification; unverified.

evidence-system

22 completers; 81-day low and supplemented Mg periods; Holter monitoring

experimental_model

22 completers; 81-day low and supplemented Mg periods; Holter monitoring

exposure

Chemically measured mean intake: 130 mg Mg/day in the low period versus 411 mg/day in the supplemented period; 81 days per period after 10-day equilibration. These are experimental exposures, not recommendations.

limitations

Ventricular ectopy alone was not significantly increased; small cohort. Dietary copper varied independently; reported Mg effect was unaffected by copper or sequence.

nutrient_topic

Magnesium research collection; topical membership is not evidence of a direct dietary effect. · Magnesium

organism

Human

plain_language

Controlled magnesium restriction produced its own measurable cardiac electrical effect.

primary_references

[klevay-2002-ectopy] Low dietary magnesium increases supraventricular ectopy (2002). https://ajcn.nutrition.org/article/S0002-9165%2823%2906154-3/fulltext DOI: 10.1093/ajcn/75.3.550

tissue

Whole-body nutrition; cardiac electrophysiology

tissue_or_cell_type

Whole-body nutrition; cardiac electrophysiology

trigger_kind

nutrient_deficiency Imported condition classification; unverified.

Magnesium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 1318–1330

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · 22 completers; 81-day low and supplemented Mg periods; Holter monitoring · source_derived_draft · unverified_draft

### low-dietary-magnesium-increases-ectopy Lower Mg intake increased supraventricular ectopy in a randomized crossover feeding study of postmenopausal women. Condition category: nutrient_deficiency nutrient_topic: Magnesium research collection; topical membership is not evidence of a direct dietary effect. plain_language: Controlled magnesium restriction produced its own measurable cardiac electrical effect. organism: Human tissue_or_cell_type: Whole-body nutrition; cardiac electrophysiology experimental_model: 22 completers; 81-day low and supplemented Mg periods; Holter monitoring limitations: Ventricular ectopy alone was not significantly increased; small cohort. Dietary copper varied independently; reported Mg effect was unaffected by copper or sequence. exposure: Chemically measured mean intake: 130 mg Mg/day in the low period versus 411 mg/day in the supplemented period; 81 days per period after 10-day equilibration. These are experimental exposures, not recommendations. evidence-system: 22 completers; 81-day low and supplemented Mg periods; Holter monitoring tissue: Whole-body nutrition; cardiac electrophysiology [klevay-2002-ectopy] Low dietary magnesium increases supraventricular ectopy (2002). https://ajcn.nutrition.org/article/S0002-9165%2823%2906154-3/fulltext DOI: 10.1093/ajcn/75.3.550

evidence_access

Primary abstract

experimental_model

EPR spin trapping and DNA gel electrophoresis.

limitations

Neither cancer prevention nor clinical copper depletion follows from this assay.

nutrient_topic

Luteolin collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Luteolin / 3′,4′,5,7-tetrahydroxyflavone

plain_language

This chemical assay showed protection rather than inevitable metal-driven damage.

primary_references

The effect of Luteolin on DNA damage mediated by a copper catalyzed Fenton reaction. · 2022 · https://pubmed.ncbi.nlm.nih.gov/34717250/ · DOI 10.1016/j.jinorgbio.2021.111635

Luteolin: metabolism, immune signaling, redox chemistry and cross-nutrient mechanisms (2026-09-19) · lines 324–330

AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · EPR spin trapping and DNA gel electrophoresis. · source_derived_draft · unverified_draft

## luteolin-copper-fenton This chemical assay showed protection rather than inevitable metal-driven damage. Luteolin–copper coordination suppressed radical formation and luteolin dose-dependently protected DNA in the Cu-Fenton assay. Model: EPR spin trapping and DNA gel electrophoresis. Limitations: Neither cancer prevention nor clinical copper depletion follows from this assay. Evidence access: Primary abstract The effect of Luteolin on DNA damage mediated by a copper catalyzed Fenton reaction. · 2022 · https://pubmed.ncbi.nlm.nih.gov/34717250/ · DOI 10.1016/j.jinorgbio.2021.111635

evidence_access

Primary abstract

experimental_model

Cell-free DNA-bound copper system.

limitations

Authors inferred physiological relevance; this experiment does not establish systemic safety or clinical synergy.

nutrient_topic

Resveratrol collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Resveratrol

plain_language

Vitamin C changes the relevant chemical context.

primary_references

Effects of trans-resveratrol on copper-dependent hydroxyl-radical formation and DNA damage: evidence for hydroxyl-radical scavenging and a novel, glutathione-sparing mechanism of action. · 2000 · https://pubmed.ncbi.nlm.nih.gov/11032413/ · DOI 10.1006/abbi.2000.1973

Resveratrol: metabolites, target selectivity and cross-nutrient mechanisms (2026-09-19) · lines 374–380

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Cell-free DNA-bound copper system. · source_derived_draft · unverified_draft

## resveratrol-ascorbate-context Vitamin C changes the relevant chemical context. With ascorbate present, resveratrol protected DNA in copper-based chemical experiments without lowering hydroxyl-radical formation rate, consistent with radical scavenging. Model: Cell-free DNA-bound copper system. Limitations: Authors inferred physiological relevance; this experiment does not establish systemic safety or clinical synergy. Evidence access: Primary abstract Effects of trans-resveratrol on copper-dependent hydroxyl-radical formation and DNA damage: evidence for hydroxyl-radical scavenging and a novel, glutathione-sparing mechanism of action. · 2000 · https://pubmed.ncbi.nlm.nih.gov/11032413/ · DOI 10.1006/abbi.2000.1973

evidence_access

Primary abstract

experimental_model

Isolated cells, permeabilized cells and nuclei.

limitations

Cancer-selective killing was a proposed interpretation, not demonstrated clinical benefit.

nutrient_topic

Resveratrol collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Resveratrol

plain_language

A metal-specific rescue helps identify the assay mechanism.

primary_references

Resveratrol mobilizes endogenous copper in human peripheral lymphocytes leading to oxidative DNA breakage: a putative mechanism for chemoprevention of cancer. · 2010 · https://pubmed.ncbi.nlm.nih.gov/20119749/ · DOI 10.1007/s11095-010-0055-4

Resveratrol: metabolites, target selectivity and cross-nutrient mechanisms (2026-09-19) · lines 390–396

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Isolated cells, permeabilized cells and nuclei. · source_derived_draft · unverified_draft

## resveratrol-copper-chelator-rescue A metal-specific rescue helps identify the assay mechanism. Copper-specific chelators, unlike tested iron/zinc chelators, inhibited resveratrol-associated DNA breakage in isolated human lymphocyte and nuclear experiments. Model: Isolated cells, permeabilized cells and nuclei. Limitations: Cancer-selective killing was a proposed interpretation, not demonstrated clinical benefit. Evidence access: Primary abstract Resveratrol mobilizes endogenous copper in human peripheral lymphocytes leading to oxidative DNA breakage: a putative mechanism for chemoprevention of cancer. · 2010 · https://pubmed.ncbi.nlm.nih.gov/20119749/ · DOI 10.1007/s11095-010-0055-4

evidence_access

Primary abstract

experimental_model

Plasmid treatment followed by E. coli transformation/sequencing.

limitations

Not demonstrated human mutagenicity from dietary resveratrol.

nutrient_topic

Resveratrol collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Resveratrol

plain_language

Copper can change an antioxidant into a pro-oxidant in an assay.

primary_references

Prooxidant activity of resveratrol in the presence of copper ions: mutagenicity in plasmid DNA. · 2005 · https://pubmed.ncbi.nlm.nih.gov/15913925/ · DOI 10.1016/j.toxlet.2005.04.001

Resveratrol: metabolites, target selectivity and cross-nutrient mechanisms (2026-09-19) · lines 366–372

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Plasmid treatment followed by E. coli transformation/sequencing. · source_derived_draft · unverified_draft

## resveratrol-copper-dna Copper can change an antioxidant into a pro-oxidant in an assay. Resveratrol/copper treatment produced plasmid sequence mutations and reduced transformation efficiency in a cell-free DNA/bacterial readout experiment. Model: Plasmid treatment followed by E. coli transformation/sequencing. Limitations: Not demonstrated human mutagenicity from dietary resveratrol. Evidence access: Primary abstract Prooxidant activity of resveratrol in the presence of copper ions: mutagenicity in plasmid DNA. · 2005 · https://pubmed.ncbi.nlm.nih.gov/15913925/ · DOI 10.1016/j.toxlet.2005.04.001

evidence_access

Primary abstract

experimental_model

Chemical assay with glutathione versus ascorbate conditions.

limitations

Not a measurement of GSH synthesis, recycling or depletion in humans.

nutrient_topic

Resveratrol collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Resveratrol

plain_language

Glutathione changes the redox reaction rather than merely adding another antioxidant label.

primary_references

Effects of trans-resveratrol on copper-dependent hydroxyl-radical formation and DNA damage: evidence for hydroxyl-radical scavenging and a novel, glutathione-sparing mechanism of action. · 2000 · https://pubmed.ncbi.nlm.nih.gov/11032413/ · DOI 10.1006/abbi.2000.1973

Resveratrol: metabolites, target selectivity and cross-nutrient mechanisms (2026-09-19) · lines 382–388

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Chemical assay with glutathione versus ascorbate conditions. · source_derived_draft · unverified_draft

## resveratrol-gsh-context Glutathione changes the redox reaction rather than merely adding another antioxidant label. In the glutathione-containing copper system, resveratrol reduced radical formation and glutathione-disulfide formation. Model: Chemical assay with glutathione versus ascorbate conditions. Limitations: Not a measurement of GSH synthesis, recycling or depletion in humans. Evidence access: Primary abstract Effects of trans-resveratrol on copper-dependent hydroxyl-radical formation and DNA damage: evidence for hydroxyl-radical scavenging and a novel, glutathione-sparing mechanism of action. · 2000 · https://pubmed.ncbi.nlm.nih.gov/11032413/ · DOI 10.1006/abbi.2000.1973

evidence_access

Primary abstract

experimental_model

Spectroscopy and competition against histidine/phenanthroline.

limitations

This is not demonstrated copper depletion in humans.

nutrient_topic

Ergothioneine collection; molecular form, preparation, species, exposure and manipulation remain explicit. · L-Ergothioneine

plain_language

Copper oxidation state matters for binding.

primary_references

Ergothioneine prevents copper-induced oxidative damage to DNA and protein by forming a redox-inactive ergothioneine-copper complex. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21047085/ · DOI 10.1021/tx100214t

Ergothioneine: transport, redox chemistry and cross-nutrient mechanisms (2026-09-19) · lines 120–126

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Spectroscopy and competition against histidine/phenanthroline. · source_derived_draft · unverified_draft

## ergothioneine-copper-binding Copper oxidation state matters for binding. Ergothioneine bound copper(I), rather than copper(II), and formed a redox-inactive complex in the tested chemical systems. Model: Spectroscopy and competition against histidine/phenanthroline. Limitations: This is not demonstrated copper depletion in humans. Evidence access: Primary abstract Ergothioneine prevents copper-induced oxidative damage to DNA and protein by forming a redox-inactive ergothioneine-copper complex. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21047085/ · DOI 10.1021/tx100214t

evidence_access

Primary abstract

experimental_model

Cell-free copper/ascorbate and copper/peroxide systems.

limitations

Exposure and free-metal speciation limit extrapolation.

nutrient_topic

Ergothioneine collection; molecular form, preparation, species, exposure and manipulation remain explicit. · L-Ergothioneine

plain_language

Binding the catalyst can protect several targets.

primary_references

Ergothioneine prevents copper-induced oxidative damage to DNA and protein by forming a redox-inactive ergothioneine-copper complex. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21047085/ · DOI 10.1021/tx100214t

Ergothioneine: transport, redox chemistry and cross-nutrient mechanisms (2026-09-19) · lines 128–134

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Cell-free copper/ascorbate and copper/peroxide systems. · source_derived_draft · unverified_draft

## ergothioneine-copper-oxidation Binding the catalyst can protect several targets. Ergothioneine at 0.1-1 mM protected DNA and albumin against 0.1 mM copper with ascorbate or peroxide. Model: Cell-free copper/ascorbate and copper/peroxide systems. Limitations: Exposure and free-metal speciation limit extrapolation. Evidence access: Primary abstract Ergothioneine prevents copper-induced oxidative damage to DNA and protein by forming a redox-inactive ergothioneine-copper complex. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21047085/ · DOI 10.1021/tx100214t

evidence_span

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experimental_model

Human endothelial-cell and extracellular LDL oxidation experiments

exposure

40–80 micromolar lipoic acid; menadione or copper/LDL challenge

limitations

Compartment and oxidant matter; intracellular vitamin C and LDL vitamin E are distinct readouts.

nutrient_topic

Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect. · Lipoic acid

organism

Human cell line and human LDL

plain_language

Protection of LDL did not guarantee protection of intracellular vitamin C.

primary_references

[ala-p18026819] alpha-Lipoic acid and ascorbate prevent LDL oxidation and oxidant stress in endothelial cells. (2008). https://pubmed.ncbi.nlm.nih.gov/18026819/ DOI: 10.1007/s11010-007-9650-z

tissue_or_cell_type

EA.hy926 endothelial cells; extracellular LDL

Alpha-lipoic acid: cofactor assembly, redox signaling and nutrient interactions (2026-09-17) · lines 1027–1038

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Human endothelial-cell and extracellular LDL oxidation experiments · source_derived_draft · unverified_draft

### ala-copper-challenge-ascorbate-null Lipoic acid did not prevent intracellular ascorbate loss caused by the extracellular copper/LDL challenge in the same study. Condition category: normal nutrient_topic: Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect. plain_language: Protection of LDL did not guarantee protection of intracellular vitamin C. organism: Human cell line and human LDL tissue_or_cell_type: EA.hy926 endothelial cells; extracellular LDL experimental_model: Human endothelial-cell and extracellular LDL oxidation experiments limitations: Compartment and oxidant matter; intracellular vitamin C and LDL vitamin E are distinct readouts. exposure: 40–80 micromolar lipoic acid; menadione or copper/LDL challenge evidence_span: {"source_cache": "artifacts/ala-research/18026819.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a4dff4887489013858d07ce07ba538c62702962afa1588ae7cc83e308648e53a", "start_char": 0, "end_char": 1329, "text_sha256": "a4dff4887489013858d07ce07ba538c62702962afa1588ae7cc83e308648e53a"} [ala-p18026819] alpha-Lipoic acid and ascorbate prevent LDL oxidation and oxidant stress in endothelial cells. (2008). https://pubmed.ncbi.nlm.nih.gov/18026819/ DOI: 10.1007/s11010-007-9650-z

evidence_span

{"source_cache": "artifacts/ala-research/9680174.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ac15770e92102947345520296b7795e8ff2dca2c345ac76c14b929fbd19739f1", "start_char": 0, "end_char": 2034, "text_sha256": "ac15770e92102947345520296b7795e8ff2dca2c345ac76c14b929fbd19739f1"}

experimental_model

Cell-free human LDL oxidation and electron-spin-resonance assays

exposure

Copper 5 micromolar; DHLA 0–20 micromolar; oxygen and pH varied

limitations

Metal binding, reduction and radical production depend on ratio, oxygen and pH; not evidence for human metal-detoxification efficacy.

nutrient_topic

Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect. · Lipoic acid

organism

Human LDL; cell-free chemistry

plain_language

Metal binding was not a permanent guarantee against oxidation.

primary_references

[ala-p9680174] Thiol chelation of Cu2+ by dihydrolipoic acid prevents human low density lipoprotein peroxidation. (1998). https://pubmed.ncbi.nlm.nih.gov/9680174/ DOI: 10.1016/s0891-5849(98)00048-3

tissue_or_cell_type

LDL and copper/DHLA solutions

Alpha-lipoic acid: cofactor assembly, redox signaling and nutrient interactions (2026-09-17) · lines 1066–1077

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cell-free human LDL oxidation and electron-spin-resonance assays · source_derived_draft · unverified_draft

### ala-dhla-copper-oxygen Oxidation destabilized DHLA-copper complexes near physiological pH, with renewed LDL oxidation and radical detection in the model. Condition category: normal nutrient_topic: Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect. plain_language: Metal binding was not a permanent guarantee against oxidation. organism: Human LDL; cell-free chemistry tissue_or_cell_type: LDL and copper/DHLA solutions experimental_model: Cell-free human LDL oxidation and electron-spin-resonance assays limitations: Metal binding, reduction and radical production depend on ratio, oxygen and pH; not evidence for human metal-detoxification efficacy. exposure: Copper 5 micromolar; DHLA 0–20 micromolar; oxygen and pH varied evidence_span: {"source_cache": "artifacts/ala-research/9680174.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ac15770e92102947345520296b7795e8ff2dca2c345ac76c14b929fbd19739f1", "start_char": 0, "end_char": 2034, "text_sha256": "ac15770e92102947345520296b7795e8ff2dca2c345ac76c14b929fbd19739f1"} [ala-p9680174] Thiol chelation of Cu2+ by dihydrolipoic acid prevents human low density lipoprotein peroxidation. (1998). https://pubmed.ncbi.nlm.nih.gov/9680174/ DOI: 10.1016/s0891-5849(98)00048-3

evidence_span

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experimental_model

Cell-free human LDL oxidation and electron-spin-resonance assays

exposure

Copper 5 micromolar; DHLA 0–20 micromolar; oxygen and pH varied

limitations

Metal binding, reduction and radical production depend on ratio, oxygen and pH; not evidence for human metal-detoxification efficacy.

nutrient_topic

Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect. · Lipoic acid

organism

Human LDL; cell-free chemistry

plain_language

Reduced and oxidized forms behaved differently in the same chemical test.

primary_references

[ala-p9680174] Thiol chelation of Cu2+ by dihydrolipoic acid prevents human low density lipoprotein peroxidation. (1998). https://pubmed.ncbi.nlm.nih.gov/9680174/ DOI: 10.1016/s0891-5849(98)00048-3

tissue_or_cell_type

LDL and copper/DHLA solutions

Alpha-lipoic acid: cofactor assembly, redox signaling and nutrient interactions (2026-09-17) · lines 1040–1051

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cell-free human LDL oxidation and electron-spin-resonance assays · source_derived_draft · unverified_draft

### ala-dhla-ldl-protection DHLA delayed copper-driven LDL oxidation, whereas oxidized lipoic acid did not protect in this cell-free assay. Condition category: normal nutrient_topic: Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect. plain_language: Reduced and oxidized forms behaved differently in the same chemical test. organism: Human LDL; cell-free chemistry tissue_or_cell_type: LDL and copper/DHLA solutions experimental_model: Cell-free human LDL oxidation and electron-spin-resonance assays limitations: Metal binding, reduction and radical production depend on ratio, oxygen and pH; not evidence for human metal-detoxification efficacy. exposure: Copper 5 micromolar; DHLA 0–20 micromolar; oxygen and pH varied evidence_span: {"source_cache": "artifacts/ala-research/9680174.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "ac15770e92102947345520296b7795e8ff2dca2c345ac76c14b929fbd19739f1", "start_char": 0, "end_char": 2034, "text_sha256": "ac15770e92102947345520296b7795e8ff2dca2c345ac76c14b929fbd19739f1"} [ala-p9680174] Thiol chelation of Cu2+ by dihydrolipoic acid prevents human low density lipoprotein peroxidation. (1998). https://pubmed.ncbi.nlm.nih.gov/9680174/ DOI: 10.1016/s0891-5849(98)00048-3

evidence_span

{"source_cache": "artifacts/ala-research/18026819.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a4dff4887489013858d07ce07ba538c62702962afa1588ae7cc83e308648e53a", "start_char": 0, "end_char": 1329, "text_sha256": "a4dff4887489013858d07ce07ba538c62702962afa1588ae7cc83e308648e53a"}

experimental_model

Human endothelial-cell and extracellular LDL oxidation experiments

exposure

40–80 micromolar lipoic acid; menadione or copper/LDL challenge

limitations

Compartment and oxidant matter; intracellular vitamin C and LDL vitamin E are distinct readouts.

nutrient_topic

Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect. · Lipoic acid

organism

Human cell line and human LDL

plain_language

The extracellular lipoprotein compartment showed less oxidative damage.

primary_references

[ala-p18026819] alpha-Lipoic acid and ascorbate prevent LDL oxidation and oxidant stress in endothelial cells. (2008). https://pubmed.ncbi.nlm.nih.gov/18026819/ DOI: 10.1007/s11010-007-9650-z

tissue_or_cell_type

EA.hy926 endothelial cells; extracellular LDL

Alpha-lipoic acid: cofactor assembly, redox signaling and nutrient interactions (2026-09-17) · lines 1014–1025

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Human endothelial-cell and extracellular LDL oxidation experiments · source_derived_draft · unverified_draft

### ala-ldl-vitamin-e-sparing Lipoic acid blunted copper-driven LDL oxidation and associated vitamin E consumption in the endothelial-cell experiment. Condition category: normal nutrient_topic: Alpha-lipoic acid research collection; topical membership is not evidence of a direct dietary effect. plain_language: The extracellular lipoprotein compartment showed less oxidative damage. organism: Human cell line and human LDL tissue_or_cell_type: EA.hy926 endothelial cells; extracellular LDL experimental_model: Human endothelial-cell and extracellular LDL oxidation experiments limitations: Compartment and oxidant matter; intracellular vitamin C and LDL vitamin E are distinct readouts. exposure: 40–80 micromolar lipoic acid; menadione or copper/LDL challenge evidence_span: {"source_cache": "artifacts/ala-research/18026819.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a4dff4887489013858d07ce07ba538c62702962afa1588ae7cc83e308648e53a", "start_char": 0, "end_char": 1329, "text_sha256": "a4dff4887489013858d07ce07ba538c62702962afa1588ae7cc83e308648e53a"} [ala-p18026819] alpha-Lipoic acid and ascorbate prevent LDL oxidation and oxidant stress in endothelial cells. (2008). https://pubmed.ncbi.nlm.nih.gov/18026819/ DOI: 10.1007/s11010-007-9650-z

evidence_access

Primary abstract

experimental_model

Rat-liver CACT proteoliposome assay.

limitations

Does not demonstrate oral glutathione-carnitine synergy.

nutrient_topic

L-Carnitine collection; isomer, preparation, species, exposure and manipulation remain explicit. · L-Carnitine

plain_language

The redox environment can change whether the carrier works.

primary_references

Effect of Copper on the Mitochondrial Carnitine/Acylcarnitine Carrier Via Interaction with Cys136 and Cys155. Possible Implications in Pathophysiology. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32070004/ · DOI 10.3390/molecules25040820

L-Carnitine: synthesis, acyl-group transport, fuel selection and nutrient interactions (2026-09-19) · lines 146–152

AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Rat-liver CACT proteoliposome assay. · source_derived_draft · unverified_draft

## l-carnitine-gsh-carrier The redox environment can change whether the carrier works. Adding reduced glutathione reversed copper inhibition of the reconstituted native rat carnitine-acylcarnitine carrier. Model: Rat-liver CACT proteoliposome assay. Limitations: Does not demonstrate oral glutathione-carnitine synergy. Evidence access: Primary abstract Effect of Copper on the Mitochondrial Carnitine/Acylcarnitine Carrier Via Interaction with Cys136 and Cys155. Possible Implications in Pathophysiology. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32070004/ · DOI 10.3390/molecules25040820

cross_nutrient

true

experimental_model

Transient expression of human SOD1 and CCS in human HEK293T cells; in-cell NMR

exposure

10 µM ZnSO4 in expression medium; 100 µM CuCl2 added after 48 h and incubated 24 h.

limitations

HEK293T cells overexpressed SOD1/CCS above endogenous levels; these medium concentrations are experimental exposures, not dietary targets. Copper transfer and disulfide oxidation need not occur in a fixed coupled step in every cellular context.

nutrient_topic

Zinc research collection; topical membership is not evidence of a direct dietary effect. · Zinc

organism

Homo sapiens

plain_language

The copper chaperone increased copper loading into zinc-containing SOD1.

primary_references

[zinc-enz-sod1-live2013] Atomic-resolution monitoring of protein maturation in live human cells by NMR. (2013). https://pubmed.ncbi.nlm.nih.gov/23455544/ DOI: 10.1038/nchembio.1202

tissue_or_cell_type

Human HEK293T cytoplasm

Zinc: transport, enzyme loading, deficiency and nutrient interactions (2026-09-17) · lines 742–753

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Transient expression of human SOD1 and CCS in human HEK293T cells; in-cell NMR · source_derived_draft · unverified_draft

### zinc-enz-sod1-copper-loading Coexpression of CCS increased Cu(I) incorporation into SOD1 after Cu(II) exposure in zinc-supplemented HEK293T cells; at higher expression the Cu(I),Zn-SOD1:E,Zn-SOD1 ratio reached about 1:1. Condition category: normal nutrient_topic: Zinc research collection; topical membership is not evidence of a direct dietary effect. plain_language: The copper chaperone increased copper loading into zinc-containing SOD1. organism: Homo sapiens tissue_or_cell_type: Human HEK293T cytoplasm experimental_model: Transient expression of human SOD1 and CCS in human HEK293T cells; in-cell NMR limitations: HEK293T cells overexpressed SOD1/CCS above endogenous levels; these medium concentrations are experimental exposures, not dietary targets. Copper transfer and disulfide oxidation need not occur in a fixed coupled step in every cellular context. exposure: 10 µM ZnSO4 in expression medium; 100 µM CuCl2 added after 48 h and incubated 24 h. cross_nutrient: true [zinc-enz-sod1-live2013] Atomic-resolution monitoring of protein maturation in live human cells by NMR. (2013). https://pubmed.ncbi.nlm.nih.gov/23455544/ DOI: 10.1038/nchembio.1202

cross_nutrient

true

experimental_model

Radiolabeled Cu(I) and Cu(II) uptake in Xenopus oocytes

exposure

Cu(I) and Cu(II) tested separately against controls.

limitations

A bounded negative result does not mean zinc and copper have no interaction through other proteins or intestinal mechanisms.

nutrient_topic

Zinc research collection; topical membership is not evidence of a direct dietary effect. · Zinc

organism

Mouse protein in Xenopus laevis oocytes

plain_language

This ZIP14 experiment found no copper transport despite detecting other metal substrates.

primary_references

[zinc-trans-21653899] Zip14 is a complex broad-scope metal-ion transporter whose functional properties support roles in the cellular uptake of zinc and nontransferrin-bound iron. (2011). https://pubmed.ncbi.nlm.nih.gov/21653899/ DOI: 10.1152/ajpcell.00479.2010

tissue_or_cell_type

Oocyte plasma membrane

Zinc: transport, enzyme loading, deficiency and nutrient interactions (2026-09-17) · lines 518–529

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Radiolabeled Cu(I) and Cu(II) uptake in Xenopus oocytes · source_derived_draft · unverified_draft

### zinc-trans-zip14-copper-negative Mouse ZIP14 did not increase uptake of radiolabeled copper supplied as Cu(I) or Cu(II) in the tested oocyte conditions. Condition category: normal nutrient_topic: Zinc research collection; topical membership is not evidence of a direct dietary effect. plain_language: This ZIP14 experiment found no copper transport despite detecting other metal substrates. organism: Mouse protein in Xenopus laevis oocytes tissue_or_cell_type: Oocyte plasma membrane experimental_model: Radiolabeled Cu(I) and Cu(II) uptake in Xenopus oocytes limitations: A bounded negative result does not mean zinc and copper have no interaction through other proteins or intestinal mechanisms. exposure: Cu(I) and Cu(II) tested separately against controls. cross_nutrient: true [zinc-trans-21653899] Zip14 is a complex broad-scope metal-ion transporter whose functional properties support roles in the cellular uptake of zinc and nontransferrin-bound iron. (2011). https://pubmed.ncbi.nlm.nih.gov/21653899/ DOI: 10.1152/ajpcell.00479.2010

evidence_access

Primary abstract

experimental_model

DNA electrophoresis and spectroscopic assays.

limitations

Prepared complex exposure is not equivalent to eating copper-containing food with fisetin.

nutrient_topic

Fisetin collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Fisetin

plain_language

Metal binding does not guarantee antioxidant protection.

primary_references

Physicochemical, antioxidant, DNA cleaving properties and antimicrobial activity of fisetin-copper chelates. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29247867/ · DOI 10.1016/j.jinorgbio.2017.12.006

Fisetin: metabolism, cell-state responses and cross-nutrient mechanisms (2026-09-19) · lines 144–150

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · DNA electrophoresis and spectroscopic assays. · source_derived_draft · unverified_draft

## fisetin-copper-dna-chemistry Metal binding does not guarantee antioxidant protection. A prepared 1:2 copper(II):fisetin complex cleaved and degraded DNA in chemical assays. Model: DNA electrophoresis and spectroscopic assays. Limitations: Prepared complex exposure is not equivalent to eating copper-containing food with fisetin. Evidence access: Primary abstract Physicochemical, antioxidant, DNA cleaving properties and antimicrobial activity of fisetin-copper chelates. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29247867/ · DOI 10.1016/j.jinorgbio.2017.12.006

evidence_access

Primary full text

experimental_model

5 micromolar fisetin with FeCl2/CuCl2 titration.

limitations

Cell-culture ratio, not a clinical spacing rule for supplements.

nutrient_topic

Fisetin collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Fisetin

plain_language

Iron weakened the signaling response under these conditions.

primary_references

Modulation of the Neuroprotective and Anti-inflammatory Activities of the Flavonol Fisetin by the Transition Metals Iron and Copper. · 2020 · https://pubmed.ncbi.nlm.nih.gov/33187316/ · DOI 10.3390/antiox9111113

Fisetin: metabolism, cell-state responses and cross-nutrient mechanisms (2026-09-19) · lines 160–166

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · 5 micromolar fisetin with FeCl2/CuCl2 titration. · source_derived_draft · unverified_draft

## fisetin-iron-signaling-antagonism Iron weakened the signaling response under these conditions. In mouse HT22 cells, added iron reduced fisetin-induced nuclear Nrf2 and ATF4 from an iron:fisetin ratio of 0.5:1; copper did not do so in the tested range. Model: 5 micromolar fisetin with FeCl2/CuCl2 titration. Limitations: Cell-culture ratio, not a clinical spacing rule for supplements. Evidence access: Primary full text Modulation of the Neuroprotective and Anti-inflammatory Activities of the Flavonol Fisetin by the Transition Metals Iron and Copper. · 2020 · https://pubmed.ncbi.nlm.nih.gov/33187316/ · DOI 10.3390/antiox9111113

evidence_access

Primary full text

experimental_model

Mouse HT22 cells; separately added FeCl2/CuCl2, 0.5-10 micromolar.

limitations

Not a dietary deficiency experiment or evidence of systemic metal removal.

nutrient_topic

Fisetin collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Fisetin

plain_language

Protection depended on the way oxidative stress was induced.

primary_references

Modulation of the Neuroprotective and Anti-inflammatory Activities of the Flavonol Fisetin by the Transition Metals Iron and Copper. · 2020 · https://pubmed.ncbi.nlm.nih.gov/33187316/ · DOI 10.3390/antiox9111113

Fisetin: metabolism, cell-state responses and cross-nutrient mechanisms (2026-09-19) · lines 152–158

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Mouse HT22 cells; separately added FeCl2/CuCl2, 0.5-10 micromolar. · source_derived_draft · unverified_draft

## fisetin-metal-gsh-protection Protection depended on the way oxidative stress was induced. At 5 micromolar, fisetin limited iron- or copper-potentiated glutathione loss and cell death in glutamate-challenged mouse HT22 cells. Model: Mouse HT22 cells; separately added FeCl2/CuCl2, 0.5-10 micromolar. Limitations: Not a dietary deficiency experiment or evidence of systemic metal removal. Evidence access: Primary full text Modulation of the Neuroprotective and Anti-inflammatory Activities of the Flavonol Fisetin by the Transition Metals Iron and Copper. · 2020 · https://pubmed.ncbi.nlm.nih.gov/33187316/ · DOI 10.3390/antiox9111113

evidence_access

Primary abstract

experimental_model

Suckling-rat tracer study; water and formula matrices.

limitations

The abstract switches to Cd when describing circulatory absorption. That sentence is not silently treated as a verified copper result; no infant recommendation follows.

nutrient_topic

Fulvic acid collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · Fulvic acid (heterogeneous humic fraction)

plain_language

Copper stayed in the intestinal lining longer.

primary_references

Intestinal absorption of copper from drinking water containing fulvic acids and an infant formula mixture studied in a suckling rat model. · 1999 · https://pubmed.ncbi.nlm.nih.gov/10406087/ · DOI 10.1023/a:1009233802104

Fulvic acid: mixture identity, mineral chemistry, signaling and cross-nutrient mechanisms (2026-09-19) · lines 84–90

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Suckling-rat tracer study; water and formula matrices. · source_derived_draft · unverified_draft

## fulvic-acid-copper-retention Copper stayed in the intestinal lining longer. Fulvic exposure increased intestinal mucosal copper retention at six hours without markedly changing lumen-to-mucosa uptake. Model: Suckling-rat tracer study; water and formula matrices. Limitations: The abstract switches to Cd when describing circulatory absorption. That sentence is not silently treated as a verified copper result; no infant recommendation follows. Evidence access: Primary abstract Intestinal absorption of copper from drinking water containing fulvic acids and an infant formula mixture studied in a suckling rat model. · 1999 · https://pubmed.ncbi.nlm.nih.gov/10406087/ · DOI 10.1023/a:1009233802104

evidence_access

Primary full text

experimental_model

Zebrafish larvae; FulvoFeed for 96 hours, wash, then copper 50 micromolar for 2 hours; ROS fluorescence assay.

limitations

mg C/L expresses organic carbon, not supplement mass. Washing reduced direct external copper-complexation confounding. ROS is an indirect inflammatory endpoint; proposed radical/aromatic explanations were not isolated genetic or binding tests. This is a concentration-dependent result, not an unexplained contradiction with the lower-dose result.

nutrient_topic

Fulvic acid collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · Fulvic acid (heterogeneous humic fraction)

plain_language

Higher tested exposures amplified the same stress readout.

primary_references

Modification of the chemically induced inflammation assay reveals the Janus face of a phenol rich fulvic acid. · 2022 · https://pubmed.ncbi.nlm.nih.gov/35393468/ · DOI 10.1038/s41598-022-09782-w

Fulvic acid: mixture identity, mineral chemistry, signaling and cross-nutrient mechanisms (2026-09-19) · lines 204–210

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Zebrafish larvae; FulvoFeed for 96 hours, wash, then copper 50 micromolar for 2 hours; ROS fluorescence assay. · source_derived_draft · unverified_draft

## fulvic-acid-zebrafish-high Higher tested exposures amplified the same stress readout. FulvoFeed at 300 or 500 mg C/L increased the subsequent copper-associated ROS response. Model: Zebrafish larvae; FulvoFeed for 96 hours, wash, then copper 50 micromolar for 2 hours; ROS fluorescence assay. Limitations: mg C/L expresses organic carbon, not supplement mass. Washing reduced direct external copper-complexation confounding. ROS is an indirect inflammatory endpoint; proposed radical/aromatic explanations were not isolated genetic or binding tests. This is a concentration-dependent result, not an unexplained contradiction with the lower-dose result. Evidence access: Primary full text Modification of the chemically induced inflammation assay reveals the Janus face of a phenol rich fulvic acid. · 2022 · https://pubmed.ncbi.nlm.nih.gov/35393468/ · DOI 10.1038/s41598-022-09782-w

evidence_access

Primary full text

experimental_model

Zebrafish larvae; FulvoFeed for 96 hours, wash, then copper 50 micromolar for 2 hours; ROS fluorescence assay.

limitations

mg C/L expresses organic carbon, not supplement mass. Washing reduced direct external copper-complexation confounding. ROS is an indirect inflammatory endpoint; proposed radical/aromatic explanations were not isolated genetic or binding tests.

nutrient_topic

Fulvic acid collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · Fulvic acid (heterogeneous humic fraction)

plain_language

Lower tested exposures dampened the stress readout.

primary_references

Modification of the chemically induced inflammation assay reveals the Janus face of a phenol rich fulvic acid. · 2022 · https://pubmed.ncbi.nlm.nih.gov/35393468/ · DOI 10.1038/s41598-022-09782-w

Fulvic acid: mixture identity, mineral chemistry, signaling and cross-nutrient mechanisms (2026-09-19) · lines 196–202

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Zebrafish larvae; FulvoFeed for 96 hours, wash, then copper 50 micromolar for 2 hours; ROS fluorescence assay. · source_derived_draft · unverified_draft

## fulvic-acid-zebrafish-low Lower tested exposures dampened the stress readout. FulvoFeed at 5 or 50 mg C/L reduced the subsequent copper-associated ROS response. Model: Zebrafish larvae; FulvoFeed for 96 hours, wash, then copper 50 micromolar for 2 hours; ROS fluorescence assay. Limitations: mg C/L expresses organic carbon, not supplement mass. Washing reduced direct external copper-complexation confounding. ROS is an indirect inflammatory endpoint; proposed radical/aromatic explanations were not isolated genetic or binding tests. Evidence access: Primary full text Modification of the chemically induced inflammation assay reveals the Janus face of a phenol rich fulvic acid. · 2022 · https://pubmed.ncbi.nlm.nih.gov/35393468/ · DOI 10.1038/s41598-022-09782-w

evidence_access

Primary full text

experimental_model

Human SH-SY5Y cells, 24 hours; 10 micrograms/mL myricetin is about 31.4 micromolar.

limitations

High copper cell-culture challenge; not evidence that ordinary copper foods plus myricetin cause neuronal injury.

nutrient_topic

Myricetin collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Myricetin

plain_language

Copper changes the outcome of this redox-active compound.

primary_references

Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33562817/ · DOI 10.3390/molecules26040845

Myricetin: metabolism, immune signaling, redox chemistry and cross-nutrient mechanisms (2026-09-19) · lines 340–346

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human SH-SY5Y cells, 24 hours; 10 micrograms/mL myricetin is about 31.4 micromolar. · source_derived_draft · unverified_draft

## myricetin-copper-atp Copper changes the outcome of this redox-active compound. With 0.5 mM CuSO4 and 10 micrograms/mL myricetin, ATP content fell to 43% of untreated control. Model: Human SH-SY5Y cells, 24 hours; 10 micrograms/mL myricetin is about 31.4 micromolar. Limitations: High copper cell-culture challenge; not evidence that ordinary copper foods plus myricetin cause neuronal injury. Evidence access: Primary full text Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33562817/ · DOI 10.3390/molecules26040845

evidence_access

Primary full text

experimental_model

Human SH-SY5Y cells, 24 hours; 10 micrograms/mL myricetin is about 31.4 micromolar.

limitations

High copper cell-culture challenge; not evidence that ordinary copper foods plus myricetin cause neuronal injury.

nutrient_topic

Myricetin collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Myricetin

plain_language

Copper changes the outcome of this redox-active compound.

primary_references

Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33562817/ · DOI 10.3390/molecules26040845

Myricetin: metabolism, immune signaling, redox chemistry and cross-nutrient mechanisms (2026-09-19) · lines 348–354

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human SH-SY5Y cells, 24 hours; 10 micrograms/mL myricetin is about 31.4 micromolar. · source_derived_draft · unverified_draft

## myricetin-copper-death Copper changes the outcome of this redox-active compound. Myricetin exacerbated copper-associated cell death, corroborated by metabolic and trypan-blue measurements. Model: Human SH-SY5Y cells, 24 hours; 10 micrograms/mL myricetin is about 31.4 micromolar. Limitations: High copper cell-culture challenge; not evidence that ordinary copper foods plus myricetin cause neuronal injury. Evidence access: Primary full text Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33562817/ · DOI 10.3390/molecules26040845

evidence_access

Primary full text

experimental_model

Human cells; 0.5 mM CuSO4, up to 10 micrograms/mL myricetin.

limitations

Do not convert proposed thiol chemistry into measured GSH depletion.

nutrient_topic

Myricetin collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Myricetin

plain_language

More injury did not require a further measured fall in glutathione.

primary_references

Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33562817/ · DOI 10.3390/molecules26040845

Myricetin: metabolism, immune signaling, redox chemistry and cross-nutrient mechanisms (2026-09-19) · lines 356–362

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human cells; 0.5 mM CuSO4, up to 10 micrograms/mL myricetin. · source_derived_draft · unverified_draft

## myricetin-copper-gsh-null More injury did not require a further measured fall in glutathione. Myricetin did not further reduce the glutathione pool already lowered by copper in this SH-SY5Y experiment. Model: Human cells; 0.5 mM CuSO4, up to 10 micrograms/mL myricetin. Limitations: Do not convert proposed thiol chemistry into measured GSH depletion. Evidence access: Primary full text Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33562817/ · DOI 10.3390/molecules26040845

availability_state

machinery_impairment Imported condition classification; unverified.

evidence_access

Primary full text

experimental_model

Human SH-SY5Y pharmacological perturbation.

limitations

Channel subtype and causal downstream steps were not resolved; no human medication interaction established.

nutrient_topic

Myricetin collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Myricetin

plain_language

Changing calcium entry altered the response.

primary_references

Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33562817/ · DOI 10.3390/molecules26040845

trigger_kind

machinery_impairment Imported condition classification; unverified.

Myricetin: metabolism, immune signaling, redox chemistry and cross-nutrient mechanisms (2026-09-19) · lines 364–370

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human SH-SY5Y pharmacological perturbation. · source_derived_draft · unverified_draft

## myricetin-copper-nifedipine Changing calcium entry altered the response. L-type calcium-channel blockade with 10 micromolar nifedipine exacerbated death during copper/myricetin exposure. Model: Human SH-SY5Y pharmacological perturbation. Limitations: Channel subtype and causal downstream steps were not resolved; no human medication interaction established. Evidence access: Primary full text Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33562817/ · DOI 10.3390/molecules26040845

evidence_access

Primary full text

experimental_model

Human SH-SY5Y cells, 24 hours; 10 micrograms/mL myricetin is about 31.4 micromolar.

limitations

High copper cell-culture challenge; not evidence that ordinary copper foods plus myricetin cause neuronal injury.

nutrient_topic

Myricetin collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Myricetin

plain_language

Copper changes the outcome of this redox-active compound.

primary_references

Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33562817/ · DOI 10.3390/molecules26040845

Myricetin: metabolism, immune signaling, redox chemistry and cross-nutrient mechanisms (2026-09-19) · lines 332–338

AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human SH-SY5Y cells, 24 hours; 10 micrograms/mL myricetin is about 31.4 micromolar. · source_derived_draft · unverified_draft

## myricetin-copper-ros Copper changes the outcome of this redox-active compound. Myricetin at 5–10 micrograms/mL increased ROS under 0.5 mM CuSO4 exposure. Model: Human SH-SY5Y cells, 24 hours; 10 micrograms/mL myricetin is about 31.4 micromolar. Limitations: High copper cell-culture challenge; not evidence that ordinary copper foods plus myricetin cause neuronal injury. Evidence access: Primary full text Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33562817/ · DOI 10.3390/molecules26040845

evidence_span

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experimental_model

Copper sequestration and biguanide analogues in cells, with mitochondrial measurements

exposure

Metformin and analogues with and without copper sequestration

limitations

A metal-dependence result using chemical sequestration and structural analogues. It does not establish that copper status in a person changes the drug’s effect.

nutrient_topic

Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. · Metformin

organism

Cultured cells

plain_language

Take copper away and the drug stops doing several of the things it normally does.

primary_references

[metformin-p22492524] Cellular responses to the metal-binding properties of metformin. (2012). https://pubmed.ncbi.nlm.nih.gov/22492524/ DOI: 10.2337/db11-0961

tissue_or_cell_type

Mitochondria and cytoplasm

Metformin: transport, molecular targets, gut mechanisms and nutrient interactions (2026-09-19) · lines 1347–1358

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Copper sequestration and biguanide analogues in cells, with mitochondrial measurements · source_derived_draft · unverified_draft

### metformin-copper-dependence-ampk Copper sequestration opposed the known actions of metformin on AMPK-dependent signalling, and biguanide metal-binding was required for regulation of AMPK, glucose production, gluconeogenic gene expression, mitochondrial respiration and mitochondrial copper binding. Condition category: normal nutrient_topic: Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. plain_language: Take copper away and the drug stops doing several of the things it normally does. organism: Cultured cells tissue_or_cell_type: Mitochondria and cytoplasm experimental_model: Copper sequestration and biguanide analogues in cells, with mitochondrial measurements limitations: A metal-dependence result using chemical sequestration and structural analogues. It does not establish that copper status in a person changes the drug’s effect. exposure: Metformin and analogues with and without copper sequestration evidence_span: {"source_cache": "artifacts/metformin-research/22492524.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a0b1587d871d78b3bccefc5a47b277191faf6bc3b070dbe43295a0b21a633c56", "start_char": 0, "end_char": 1526, "text_sha256": "a0b1587d871d78b3bccefc5a47b277191faf6bc3b070dbe43295a0b21a633c56"} [metformin-p22492524] Cellular responses to the metal-binding properties of metformin. (2012). https://pubmed.ncbi.nlm.nih.gov/22492524/ DOI: 10.2337/db11-0961

evidence_span

{"source_cache": "artifacts/metformin-research/28530702.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "885eedb24772fbd218ff6497da6c39f486d0e0b0293ddd97e8fd7b3f23330b11", "start_char": 0, "end_char": 1137, "text_sha256": "885eedb24772fbd218ff6497da6c39f486d0e0b0293ddd97e8fd7b3f23330b11"}

experimental_model

Four-month double-blind randomised trial with faecal transfer to germ-free mice and a gut simulator

exposure

Metformin or placebo for 4 months in treatment-naive type 2 diabetes

limitations

The faecal transfer carries the causal claim. The metalloprotein observation is a genomic annotation, not a measured metal interaction.

nutrient_topic

Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. · Metformin

organism

Human and mouse

plain_language

The genes the drug touched in bacteria were unusually often metal-handling genes.

primary_references

[metformin-p28530702] Metformin alters the gut microbiome of individuals with treatment-naive type 2 diabetes, contributing to the therapeutic effects of the drug. (2017). https://pubmed.ncbi.nlm.nih.gov/28530702/ DOI: 10.1038/nm.4345

tissue_or_cell_type

Gut microbiome

Metformin: transport, molecular targets, gut mechanisms and nutrient interactions (2026-09-19) · lines 931–942

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Four-month double-blind randomised trial with faecal transfer to germ-free mice and a gut simulator · source_derived_draft · unverified_draft

### metformin-microbial-metalloproteins In a gut simulator, many of the metformin-regulated genes in species from two different phyla encoded metalloproteins or metal transporters. Condition category: normal nutrient_topic: Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. plain_language: The genes the drug touched in bacteria were unusually often metal-handling genes. organism: Human and mouse tissue_or_cell_type: Gut microbiome experimental_model: Four-month double-blind randomised trial with faecal transfer to germ-free mice and a gut simulator limitations: The faecal transfer carries the causal claim. The metalloprotein observation is a genomic annotation, not a measured metal interaction. exposure: Metformin or placebo for 4 months in treatment-naive type 2 diabetes evidence_span: {"source_cache": "artifacts/metformin-research/28530702.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "885eedb24772fbd218ff6497da6c39f486d0e0b0293ddd97e8fd7b3f23330b11", "start_char": 0, "end_char": 1137, "text_sha256": "885eedb24772fbd218ff6497da6c39f486d0e0b0293ddd97e8fd7b3f23330b11"} [metformin-p28530702] Metformin alters the gut microbiome of individuals with treatment-naive type 2 diabetes, contributing to the therapeutic effects of the drug. (2017). https://pubmed.ncbi.nlm.nih.gov/28530702/ DOI: 10.1038/nm.4345

evidence_access

Primary abstract

experimental_model

Cell-free metal-catalyzed oxidation.

limitations

Millimolar assay; does not show safe systemic metal chelation.

nutrient_topic

Carnosine collection; isomer, preparation, species, exposure and manipulation remain explicit. · L-Carnosine / beta-alanyl-L-histidine

plain_language

Its chemical protection depended on the oxidation system.

primary_references

Antioxidant properties of carnosine re-evaluated with oxidizing systems involving iron and copper ions. · 2005 · https://pubmed.ncbi.nlm.nih.gov/15853927/ · DOI 10.1111/j.1742-7843.2005.pto_03.x

Carnosine: synthesis, transport, carbonyl chemistry and nutrient interactions (2026-09-19) · lines 308–314

AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Cell-free metal-catalyzed oxidation. · source_derived_draft · unverified_draft

## carnosine-metal-dna Its chemical protection depended on the oxidation system. At 10 mM, carnosine reduced DNA damage caused by copper- or iron/peroxide/ascorbate systems. Model: Cell-free metal-catalyzed oxidation. Limitations: Millimolar assay; does not show safe systemic metal chelation. Evidence access: Primary abstract Antioxidant properties of carnosine re-evaluated with oxidizing systems involving iron and copper ions. · 2005 · https://pubmed.ncbi.nlm.nih.gov/15853927/ · DOI 10.1111/j.1742-7843.2005.pto_03.x

evidence_access

Primary abstract

experimental_model

Cell-free LDL oxidation.

limitations

Cannot distinguish all contributions of trapping and oxidation suppression.

nutrient_topic

Carnosine collection; isomer, preparation, species, exposure and manipulation remain explicit. · L-Carnosine / beta-alanyl-L-histidine

plain_language

Aldehyde availability changed in an oxidizing lipid preparation.

primary_references

Dietary carnosine prevents early atherosclerotic lesion formation in apolipoprotein E-null mice. · 2013 · https://pubmed.ncbi.nlm.nih.gov/23559625/ · DOI 10.1161/ATVBAHA.112.300572

Carnosine: synthesis, transport, carbonyl chemistry and nutrient interactions (2026-09-19) · lines 324–330

AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Cell-free LDL oxidation. · source_derived_draft · unverified_draft

## carnosine-oxidized-ldl Aldehyde availability changed in an oxidizing lipid preparation. Adding carnosine lowered free HNE formation during copper-driven LDL oxidation. Model: Cell-free LDL oxidation. Limitations: Cannot distinguish all contributions of trapping and oxidation suppression. Evidence access: Primary abstract Dietary carnosine prevents early atherosclerotic lesion formation in apolipoprotein E-null mice. · 2013 · https://pubmed.ncbi.nlm.nih.gov/23559625/ · DOI 10.1161/ATVBAHA.112.300572

evidence_access

Primary abstract

experimental_model

Chemical analysis, mouse tissues and human neuroblastoma cells.

limitations

Product formation is distinct from simple removal of oxidants.

nutrient_topic

Carnosine collection; isomer, preparation, species, exposure and manipulation remain explicit. · L-Carnosine / beta-alanyl-L-histidine

plain_language

An oxidation product can retain biological activity.

primary_references

2-Oxo-histidine-containing dipeptides are functional oxidation products. · 2019 · https://pubmed.ncbi.nlm.nih.gov/30504220/ · DOI 10.1074/jbc.RA118.006111

Carnosine: synthesis, transport, carbonyl chemistry and nutrient interactions (2026-09-19) · lines 340–346

AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Chemical analysis, mouse tissues and human neuroblastoma cells. · source_derived_draft · unverified_draft

## carnosine-oxo-product An oxidation product can retain biological activity. Oxidation of carnosine produced 2-oxo-carnosine; mechanistic analysis supported imidazole-radical formation followed by oxygen addition. Model: Chemical analysis, mouse tissues and human neuroblastoma cells. Limitations: Product formation is distinct from simple removal of oxidants. Evidence access: Primary abstract 2-Oxo-histidine-containing dipeptides are functional oxidation products. · 2019 · https://pubmed.ncbi.nlm.nih.gov/30504220/ · DOI 10.1074/jbc.RA118.006111

experimental_model

LOXL2 assay development and total-family activity detection in cultured cells and tissue.

limitations

Substrate sites and enzyme-family members differ; peroxide production alone does not establish systemic oxidative injury.

organism

Mammalian cells/tissues and recombinant LOXL2; see study methods

plain_language

An enzyme creates reactive attachment sites used in matrix cross-linking.

primary_references

[lox-assay-2021] An in situ activity assay for lysyl oxidases (2021). https://pubmed.ncbi.nlm.nih.gov/34226627/

tissue_or_cell_type

Not specified as a whole tissue; see experimental model.

L-Lysine: mechanism-first literature curation (2026-09-17) · lines 467–475

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · LOXL2 assay development and total-family activity detection in cultured cells and tissue. · source_derived_draft · unverified_draft

### lox-peptidyl-lysine-oxidation Lysyl oxidase converts suitable peptidyl lysines to allysine, producing ammonia and hydrogen peroxide. Plain language: An enzyme creates reactive attachment sites used in matrix cross-linking. Condition category: normal organism: Mammalian cells/tissues and recombinant LOXL2; see study methods tissue_or_cell_type: Not specified as a whole tissue; see experimental model. experimental_model: LOXL2 assay development and total-family activity detection in cultured cells and tissue. limitations: Substrate sites and enzyme-family members differ; peroxide production alone does not establish systemic oxidative injury. [lox-assay-2021] An in situ activity assay for lysyl oxidases (2021). https://pubmed.ncbi.nlm.nih.gov/34226627/

dose

25-100 micromolar pigment added to plasma; copper-triggered LDL oxidation

duration

Kinetic oxidation assay; incubation duration not specified in accessed abstract

evidence_access

Primary PubMed abstract; detailed exposure for PMID 23931157 additionally checked in publisher results. No uninspected full text is claimed.

evidence_scope

literature_reviewed; source-derived curation, not universally established human effects

experimental_model

Human pooled plasma from 10 healthy donors; isolated LDL

limitations

Plasma spiking exceeds typical dietary parent-pigment exposure; vitamin synergy refers only to this assay.

nutrient_topic

Betalains collection; each molecular form, species, exposure and preparation remains explicit. · Betalains

organism

Human pooled plasma from 10 healthy donors; isolated LDL

plain_language

LDL enriched with betanin showed a longer lag before copper-induced oxidation.

primary_references

Increased resistance to oxidation of betalain-enriched human low density lipoproteins. (2003). https://pubmed.ncbi.nlm.nih.gov/12868496/ DOI: 10.1080/1071576031000097490

route

Ex vivo spiking, not oral dosing

tissue

Plasma and LDL

Betalains: mechanisms, molecular forms and cross-actor connections (2026-09-20) · lines 57–65

Original AI-assisted curation of twelve primary research papers; study-specific PubMed/DOI links and limitations retained. Not publisher full text. · supports · Human pooled plasma from 10 healthy donors; isolated LDL · source_derived_draft · unverified_draft

## betalains-betanin-ldl-oxidation LDL enriched with betanin showed a longer lag before copper-induced oxidation. Model/species: Human pooled plasma from 10 healthy donors; isolated LDL Tissue: Plasma and LDL Exposure: 25-100 micromolar pigment added to plasma; copper-triggered LDL oxidation Route: Ex vivo spiking, not oral dosing Duration: Kinetic oxidation assay; incubation duration not specified in accessed abstract Limits: Plasma spiking exceeds typical dietary parent-pigment exposure; vitamin synergy refers only to this assay. Primary reference: Increased resistance to oxidation of betalain-enriched human low density lipoproteins. (2003). https://pubmed.ncbi.nlm.nih.gov/12868496/ DOI: 10.1080/1071576031000097490

dose

25-100 micromolar pigment added to plasma; copper-triggered LDL oxidation

duration

Kinetic oxidation assay; incubation duration not specified in accessed abstract

evidence_access

Primary PubMed abstract; detailed exposure for PMID 23931157 additionally checked in publisher results. No uninspected full text is claimed.

evidence_scope

literature_reviewed; source-derived curation, not universally established human effects

experimental_model

Human pooled plasma from 10 healthy donors; isolated LDL

limitations

Plasma spiking exceeds typical dietary parent-pigment exposure; vitamin synergy refers only to this assay.

nutrient_topic

Betalains collection; each molecular form, species, exposure and preparation remains explicit. · Betalains

organism

Human pooled plasma from 10 healthy donors; isolated LDL

plain_language

LDL enriched with indicaxanthin showed a longer lag before copper-induced oxidation.

primary_references

Increased resistance to oxidation of betalain-enriched human low density lipoproteins. (2003). https://pubmed.ncbi.nlm.nih.gov/12868496/ DOI: 10.1080/1071576031000097490

route

Ex vivo spiking, not oral dosing

tissue

Plasma and LDL

Betalains: mechanisms, molecular forms and cross-actor connections (2026-09-20) · lines 77–85

Original AI-assisted curation of twelve primary research papers; study-specific PubMed/DOI links and limitations retained. Not publisher full text. · supports · Human pooled plasma from 10 healthy donors; isolated LDL · source_derived_draft · unverified_draft

## betalains-indicaxanthin-ldl-oxidation LDL enriched with indicaxanthin showed a longer lag before copper-induced oxidation. Model/species: Human pooled plasma from 10 healthy donors; isolated LDL Tissue: Plasma and LDL Exposure: 25-100 micromolar pigment added to plasma; copper-triggered LDL oxidation Route: Ex vivo spiking, not oral dosing Duration: Kinetic oxidation assay; incubation duration not specified in accessed abstract Limits: Plasma spiking exceeds typical dietary parent-pigment exposure; vitamin synergy refers only to this assay. Primary reference: Increased resistance to oxidation of betalain-enriched human low density lipoproteins. (2003). https://pubmed.ncbi.nlm.nih.gov/12868496/ DOI: 10.1080/1071576031000097490

cross_nutrient

Vitamin C chemistry in collagen, modified-lysine/carnitine metabolism or copper-dependent peptide/catecholamine processing.

experimental_model

Bovine intermediate-pituitary secretory-granule kinetic assay

exposure

Synthetic D-Tyr-Val-Gly amidation with varied ascorbate, oxygen and divalent-metal chelators/copper.

limitations

The old granule preparation is not a purified modern PAM-domain assay; synthetic substrate kinetics do not quantify all hormone amidation.

nutrient_topic

Vitamin C research collection; topical membership is not evidence of a direct dietary effect. · Vitamin C

organism

Bos taurus

plain_language

Vitamin C helps the pituitary enzyme finish a peptide with an amide group.

primary_references

[pam1983] Identification in pituitary tissue of a peptide alpha-amidation activity that acts on glycine-extended peptides and requires molecular oxygen, copper, and ascorbic acid. (1983). https://pubmed.ncbi.nlm.nih.gov/6576381/ DOI: 10.1073/pnas.80.16.5144

tissue_or_cell_type

Pituitary secretory granules

Vitamin C: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 859–870

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Bovine intermediate-pituitary secretory-granule kinetic assay · source_derived_draft · unverified_draft

### vc-enzyme-bovine-amidation-ascorbate Bovine intermediate-pituitary granule amidation of D-Tyr-Val-Gly responded to ascorbate, with apparent substrate Km and Vmax changing as the ascorbate concentration changed. Condition category: normal nutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect. plain_language: Vitamin C helps the pituitary enzyme finish a peptide with an amide group. organism: Bos taurus tissue_or_cell_type: Pituitary secretory granules experimental_model: Bovine intermediate-pituitary secretory-granule kinetic assay limitations: The old granule preparation is not a purified modern PAM-domain assay; synthetic substrate kinetics do not quantify all hormone amidation. cross_nutrient: Vitamin C chemistry in collagen, modified-lysine/carnitine metabolism or copper-dependent peptide/catecholamine processing. exposure: Synthetic D-Tyr-Val-Gly amidation with varied ascorbate, oxygen and divalent-metal chelators/copper. [pam1983] Identification in pituitary tissue of a peptide alpha-amidation activity that acts on glycine-extended peptides and requires molecular oxygen, copper, and ascorbic acid. (1983). https://pubmed.ncbi.nlm.nih.gov/6576381/ DOI: 10.1073/pnas.80.16.5144

cross_nutrient

Vitamin C chemistry in collagen, modified-lysine/carnitine metabolism or copper-dependent peptide/catecholamine processing.

experimental_model

Bovine dopamine beta-hydroxylase X-ray absorption and EXAFS

exposure

Ascorbate reduction of purified Cu(II)-DBH to Cu(I)-DBH.

limitations

Purified bovine enzyme, not a dietary copper-status measurement. Scott 1988 and Blumberg 1989 disagree on the detailed coordination change and heavy-atom ligation; this record retains only the shared Cu(II)-to-Cu(I) redox conclusion.

nutrient_topic

Vitamin C research collection; topical membership is not evidence of a direct dietary effect. · Vitamin C

organism

Bos taurus

plain_language

Vitamin C supplies reducing power to copper held inside this neurotransmitter enzyme.

primary_references

[scott1988] The copper sites of dopamine beta-hydroxylase: an X-ray absorption spectroscopic study. (1988). https://pubmed.ncbi.nlm.nih.gov/3179263/ DOI: 10.1021/bi00415a005 [blumberg1989] X-ray absorption spectroscopic study of the active copper sites in dopamine beta-hydroxylase. (1989). https://pubmed.ncbi.nlm.nih.gov/2703478/ DOI: 10.1016/s0021-9258(18)83307-5

tissue_or_cell_type

Adrenal-medullary enzyme preparation

Vitamin C: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 793–805

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Bovine dopamine beta-hydroxylase X-ray absorption and EXAFS · source_derived_draft · unverified_draft

### vc-enzyme-dbh-copper-reduction Ascorbate reduced enzyme-bound copper in purified bovine dopamine beta-hydroxylase from Cu(II) to Cu(I), as examined by X-ray absorption spectroscopy. Condition category: normal nutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect. plain_language: Vitamin C supplies reducing power to copper held inside this neurotransmitter enzyme. organism: Bos taurus tissue_or_cell_type: Adrenal-medullary enzyme preparation experimental_model: Bovine dopamine beta-hydroxylase X-ray absorption and EXAFS limitations: Purified bovine enzyme, not a dietary copper-status measurement. Scott 1988 and Blumberg 1989 disagree on the detailed coordination change and heavy-atom ligation; this record retains only the shared Cu(II)-to-Cu(I) redox conclusion. cross_nutrient: Vitamin C chemistry in collagen, modified-lysine/carnitine metabolism or copper-dependent peptide/catecholamine processing. exposure: Ascorbate reduction of purified Cu(II)-DBH to Cu(I)-DBH. [scott1988] The copper sites of dopamine beta-hydroxylase: an X-ray absorption spectroscopic study. (1988). https://pubmed.ncbi.nlm.nih.gov/3179263/ DOI: 10.1021/bi00415a005 [blumberg1989] X-ray absorption spectroscopic study of the active copper sites in dopamine beta-hydroxylase. (1989). https://pubmed.ncbi.nlm.nih.gov/2703478/ DOI: 10.1016/s0021-9258(18)83307-5

cross_nutrient

Vitamin C chemistry in collagen, modified-lysine/carnitine metabolism or copper-dependent peptide/catecholamine processing.

experimental_model

Purified bovine pituitary PAL and bovine-domain expression constructs in HEK293 cells

exposure

Purified PAL with N-acetyl-Tyr-Val-alpha-hydroxyglycine; PHM or PAL-containing constructs expressed in HEK293.

limitations

Bovine protein expressed in human cells is not a human PAM protein; domain construct activity does not quantify tissue hormone synthesis.

nutrient_topic

Vitamin C research collection; topical membership is not evidence of a direct dietary effect. · Vitamin C

organism

Bos taurus (protein); Homo sapiens (expression host)

plain_language

Peptide amidation begins with a separate vitamin-C-dependent hydroxylation step.

primary_references

[pal1991] Peptidyl-alpha-hydroxyglycine alpha-amidating lyase. Purification, characterization, and expression. (1991). https://pubmed.ncbi.nlm.nih.gov/1902227/ DOI: 10.1016/s0021-9258(20)89524-6

tissue_or_cell_type

Bovine neurointermediate pituitary; heterologous HEK293

Vitamin C: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 885–896

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified bovine pituitary PAL and bovine-domain expression constructs in HEK293 cells · source_derived_draft · unverified_draft

### vc-enzyme-pam-two-domains Expression of the bovine PHM-only construct in HEK293 cells increased secreted PHM activity, demonstrating a functional hydroxylating domain separable from the PAL portion of PAM. Condition category: normal nutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect. plain_language: Peptide amidation begins with a separate vitamin-C-dependent hydroxylation step. organism: Bos taurus (protein); Homo sapiens (expression host) tissue_or_cell_type: Bovine neurointermediate pituitary; heterologous HEK293 experimental_model: Purified bovine pituitary PAL and bovine-domain expression constructs in HEK293 cells limitations: Bovine protein expressed in human cells is not a human PAM protein; domain construct activity does not quantify tissue hormone synthesis. cross_nutrient: Vitamin C chemistry in collagen, modified-lysine/carnitine metabolism or copper-dependent peptide/catecholamine processing. exposure: Purified PAL with N-acetyl-Tyr-Val-alpha-hydroxyglycine; PHM or PAL-containing constructs expressed in HEK293. [pal1991] Peptidyl-alpha-hydroxyglycine alpha-amidating lyase. Purification, characterization, and expression. (1991). https://pubmed.ncbi.nlm.nih.gov/1902227/ DOI: 10.1016/s0021-9258(20)89524-6