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.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
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.
What acts on it
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 evidenceDHFR 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 evidence5-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
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.