Component

Endothelial nitric oxide synthase uncoupling, model specified

Endothelial nitric oxide synthase uncoupling, model specified. Species, exposure and limitations are retained in each linked claim.

3 recorded relationships. Experimental role, claim status and evidence remain attached to each record.

How nutrients influence it

Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.

How nutrients reach it in more than one step

Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.

Tracing routes…

What it does

Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.

Recorded relationships

What acts on it

  1. BH4 oxidation accompanied eNOS uncoupling with increased ROS and reduced NO in hypertensive mouse aortas.

    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/citrulline-research/12697739.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "d56604695c8c1bda167b76198a472d814d284a3c0c1e1e1eed8943cce31d0ad0", "start_char": 0, "end_char": 1474, "text_sha256": "d56604695c8c1bda167b76198a472d814d284a3c0c1e1e1eed8943cce31d0ad0"}
    experimental_model
    Hypertension and knockout mouse experiments
    exposure
    NADPH-oxidase/NOS genetic comparisons and BH4 treatment
    limitations
    Disease model; the exact response cannot be assumed in people taking citrulline.
    nutrient_topic
    Citrulline research collection; topical membership is not evidence of a direct dietary effect. · L-Citrulline
    organism
    Mouse DOCA-salt hypertension model
    plain_language
    Adding precursor is different from fixing a damaged cofactor system.
    primary_references
    [citrulline-p12697739] Oxidation of tetrahydrobiopterin leads to uncoupling of endothelial cell nitric oxide synthase in hypertension. (2003). https://pubmed.ncbi.nlm.nih.gov/12697739/ DOI: 10.1172/jci14172
    tissue_or_cell_type
    Aortic redox state and NO signaling

    Citrulline: arginine recycling, nitrogen disposal and nutrient connections (2026-09-17) · lines 801–812

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Hypertension and knockout mouse experiments · source_derived_draft · unverified_draft

    ### citrulline-bh4-oxidation BH4 oxidation accompanied eNOS uncoupling with increased ROS and reduced NO in hypertensive mouse aortas. Condition category: normal nutrient_topic: Citrulline research collection; topical membership is not evidence of a direct dietary effect. plain_language: Adding precursor is different from fixing a damaged cofactor system. organism: Mouse DOCA-salt hypertension model tissue_or_cell_type: Aortic redox state and NO signaling experimental_model: Hypertension and knockout mouse experiments limitations: Disease model; the exact response cannot be assumed in people taking citrulline. exposure: NADPH-oxidase/NOS genetic comparisons and BH4 treatment evidence_span: {"source_cache": "artifacts/citrulline-research/12697739.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "d56604695c8c1bda167b76198a472d814d284a3c0c1e1e1eed8943cce31d0ad0", "start_char": 0, "end_char": 1474, "text_sha256": "d56604695c8c1bda167b76198a472d814d284a3c0c1e1e1eed8943cce31d0ad0"} [citrulline-p12697739] Oxidation of tetrahydrobiopterin leads to uncoupling of endothelial cell nitric oxide synthase in hypertension. (2003). https://pubmed.ncbi.nlm.nih.gov/12697739/ DOI: 10.1172/jci14172
    Complete structured claim and evidence
  2. DHFR loss increased eNOS-dependent superoxide while reducing NO production.

    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    evidence_span
    {"source_cache": "artifacts/citrulline-research/19666465.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "b1ef76ebbd312932011edd1b0f9f428026a4e4cdd53301bd66f99eaf543e77af", "start_char": 0, "end_char": 1716, "text_sha256": "b1ef76ebbd312932011edd1b0f9f428026a4e4cdd53301bd66f99eaf543e77af"}
    experimental_model
    DHFR knockdown/inhibition and controlled GTPCH-expression cell experiments
    exposure
    Methotrexate or RNA interference; comparison with GTPCH knockdown
    limitations
    Mouse models; DHFR also handles folate, but this study does not make folate and BH4 interchangeable.
    nutrient_topic
    Citrulline research collection; topical membership is not evidence of a direct dietary effect. · L-Citrulline
    organism
    Mouse endothelial and NIH-3T3-based experimental cell systems
    plain_language
    A damaged cofactor balance can change the enzyme output.
    primary_references
    [citrulline-p19666465] Critical role for tetrahydrobiopterin recycling by dihydrofolate reductase in regulation of endothelial nitric-oxide synthase coupling: relative importance of the de novo biopterin synthesis versus salvage pathways. (2009). https://pubmed.ncbi.nlm.nih.gov/19666465/ DOI: 10.1074/jbc.m109.041483
    tissue_or_cell_type
    BH4/BH2 balance and NOS coupling
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Citrulline: arginine recycling, nitrogen disposal and nutrient connections (2026-09-17) · lines 788–799

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · DHFR knockdown/inhibition and controlled GTPCH-expression cell experiments · source_derived_draft · unverified_draft

    ### citrulline-dhfr-uncoupling DHFR loss increased eNOS-dependent superoxide while reducing NO production. Condition category: machinery_impairment nutrient_topic: Citrulline research collection; topical membership is not evidence of a direct dietary effect. plain_language: A damaged cofactor balance can change the enzyme output. organism: Mouse endothelial and NIH-3T3-based experimental cell systems tissue_or_cell_type: BH4/BH2 balance and NOS coupling experimental_model: DHFR knockdown/inhibition and controlled GTPCH-expression cell experiments limitations: Mouse models; DHFR also handles folate, but this study does not make folate and BH4 interchangeable. exposure: Methotrexate or RNA interference; comparison with GTPCH knockdown evidence_span: {"source_cache": "artifacts/citrulline-research/19666465.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "b1ef76ebbd312932011edd1b0f9f428026a4e4cdd53301bd66f99eaf543e77af", "start_char": 0, "end_char": 1716, "text_sha256": "b1ef76ebbd312932011edd1b0f9f428026a4e4cdd53301bd66f99eaf543e77af"} [citrulline-p19666465] Critical role for tetrahydrobiopterin recycling by dihydrofolate reductase in regulation of endothelial nitric-oxide synthase coupling: relative importance of the de novo biopterin synthesis versus salvage pathways. (2009). https://pubmed.ncbi.nlm.nih.gov/19666465/ DOI: 10.1074/jbc.m109.041483
    Complete structured claim and evidence
  3. 5-MTHF improved eNOS coupling and increased its dimer-to-monomer ratio and activity in the human vessel study.

    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/citrulline-research/16940192.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "42c07dd0bbacfc1ff44f78d6ce69810a58946e53c76bf5d3bf8385db5278ba8b", "start_char": 0, "end_char": 1942, "text_sha256": "42c07dd0bbacfc1ff44f78d6ce69810a58946e53c76bf5d3bf8385db5278ba8b"}
    experimental_model
    Ex-vivo vessel exposure and randomized pre-harvest infusion
    exposure
    5-MTHF ex vivo 1-100 micromolar; intravenous 5-MTHF or placebo in a separate subset
    limitations
    Uses 5-MTHF and acute vessel endpoints; cannot be generalized to all folic-acid doses or combination supplements.
    nutrient_topic
    Citrulline research collection; topical membership is not evidence of a direct dietary effect. · L-Citrulline
    organism
    Human, vessels from 117 CABG patients
    plain_language
    The enzyme used its electron supply more productively under the tested conditions.
    primary_references
    [citrulline-p16940192] 5-methyltetrahydrofolate rapidly improves endothelial function and decreases superoxide production in human vessels: effects on vascular tetrahydrobiopterin availability and endothelial nitric oxide synthase coupling. (2006). https://pubmed.ncbi.nlm.nih.gov/16940192/ DOI: 10.1161/circulationaha.106.612325
    tissue_or_cell_type
    Saphenous veins and internal mammary arteries

    Citrulline: arginine recycling, nitrogen disposal and nutrient connections (2026-09-17) · lines 749–760

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Ex-vivo vessel exposure and randomized pre-harvest infusion · source_derived_draft · unverified_draft

    ### citrulline-folate-coupling 5-MTHF improved eNOS coupling and increased its dimer-to-monomer ratio and activity in the human vessel study. Condition category: normal nutrient_topic: Citrulline research collection; topical membership is not evidence of a direct dietary effect. plain_language: The enzyme used its electron supply more productively under the tested conditions. organism: Human, vessels from 117 CABG patients tissue_or_cell_type: Saphenous veins and internal mammary arteries experimental_model: Ex-vivo vessel exposure and randomized pre-harvest infusion limitations: Uses 5-MTHF and acute vessel endpoints; cannot be generalized to all folic-acid doses or combination supplements. exposure: 5-MTHF ex vivo 1-100 micromolar; intravenous 5-MTHF or placebo in a separate subset evidence_span: {"source_cache": "artifacts/citrulline-research/16940192.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "42c07dd0bbacfc1ff44f78d6ce69810a58946e53c76bf5d3bf8385db5278ba8b", "start_char": 0, "end_char": 1942, "text_sha256": "42c07dd0bbacfc1ff44f78d6ce69810a58946e53c76bf5d3bf8385db5278ba8b"} [citrulline-p16940192] 5-methyltetrahydrofolate rapidly improves endothelial function and decreases superoxide production in human vessels: effects on vascular tetrahydrobiopterin availability and endothelial nitric oxide synthase coupling. (2006). https://pubmed.ncbi.nlm.nih.gov/16940192/ DOI: 10.1161/circulationaha.106.612325
    Complete structured claim and evidence

In the sources

Preserved passages that mention this component, quoted exactly. Open one to read it in context.

    This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.

    Evidence, AI assistance and curation standards