Component

Menadione / vitamin K3

Menadione / vitamin K3. Species, exposure and limitations are retained in each linked claim.

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

Read recorded mechanisms Open recursive mind map

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. Rat tracer experiments identified menadione derived from oral phylloquinone as a circulating precursor of tissue MK-4.

    Phylloquinone → Menadione / vitamin K3 source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/k2-research/24085302.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a0197882d517aa2bd4d9b2919e72c588383ad183064f1a2bf8f64f5152d28386", "start_char": 0, "end_char": 1653, "text_sha256": "a0197882d517aa2bd4d9b2919e72c588383ad183064f1a2bf8f64f5152d28386"}
    experimental_model
    Stable-isotope cannulation and recombinant-enzyme product analysis
    exposure
    Oral labeled phylloquinone; MS and NMR analysis
    limitations
    Rat tracing defines a precursor route; no exact human conversion fraction or advice to ingest menadione is inferred.
    nutrient_topic
    Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin K2 / menaquinone family
    organism
    Rats and recombinant UBIAD1
    plain_language
    K1 and K2 metabolism connect through a precursor; they are not completely separate nutritional systems.
    primary_references
    [k2-p24085302] Menadione (vitamin K3) is a catabolic product of oral phylloquinone (vitamin K1) in the intestine and a circulating precursor of tissue menaquinone-4 (vitamin K2) in rats. (2013). https://pubmed.ncbi.nlm.nih.gov/24085302/ DOI: 10.1074/jbc.m113.477356
    tissue_or_cell_type
    Intestine, circulation and tissue synthesis

    Vitamin K2: menaquinone forms, carboxylation, recycling and nutrient interactions (2026-09-17) · lines 175–186

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Stable-isotope cannulation and recombinant-enzyme product analysis · source_derived_draft · unverified_draft

    ### k2-k1-menadione Rat tracer experiments identified menadione derived from oral phylloquinone as a circulating precursor of tissue MK-4. Condition category: normal nutrient_topic: Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect. plain_language: K1 and K2 metabolism connect through a precursor; they are not completely separate nutritional systems. organism: Rats and recombinant UBIAD1 tissue_or_cell_type: Intestine, circulation and tissue synthesis experimental_model: Stable-isotope cannulation and recombinant-enzyme product analysis limitations: Rat tracing defines a precursor route; no exact human conversion fraction or advice to ingest menadione is inferred. exposure: Oral labeled phylloquinone; MS and NMR analysis evidence_span: {"source_cache": "artifacts/k2-research/24085302.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a0197882d517aa2bd4d9b2919e72c588383ad183064f1a2bf8f64f5152d28386", "start_char": 0, "end_char": 1653, "text_sha256": "a0197882d517aa2bd4d9b2919e72c588383ad183064f1a2bf8f64f5152d28386"} [k2-p24085302] Menadione (vitamin K3) is a catabolic product of oral phylloquinone (vitamin K1) in the intestine and a circulating precursor of tissue menaquinone-4 (vitamin K2) in rats. (2013). https://pubmed.ncbi.nlm.nih.gov/24085302/ DOI: 10.1074/jbc.m113.477356
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. Against menadione, melatonin showed uncompetitive NQO2 inhibition with Ki about 92 micromolar.

    Melatonin → Human quinone reductase 2 / NQO2 source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/melatonin-research/18254726.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4b99428e7457cd7b67c75ef01b056609dcdf6d5d36cf1c0e933607e2be485c18", "start_char": 0, "end_char": 1724, "text_sha256": "4b99428e7457cd7b67c75ef01b056609dcdf6d5d36cf1c0e933607e2be485c18"}
    experimental_model
    Kinetics, calorimetry and crystal structures
    exposure
    Melatonin versus N-methyldihydronicotinamide or menadione in enzyme assays
    limitations
    NQO2 is the historically named MT3 binding site, not a third MT1/MT2-like GPCR. Micromolar inhibition does not establish the dominant effect at physiological blood concentrations.
    nutrient_topic
    Melatonin research collection; topical membership is not evidence of a direct dietary effect. · Melatonin
    organism
    Purified human NQO2/QR2
    plain_language
    The inhibition pattern depends on which reaction participant is varied.
    primary_references
    [melatonin-p18254726] Kinetic, thermodynamic and X-ray structural insights into the interaction of melatonin and analogues with quinone reductase 2. (2008). https://pubmed.ncbi.nlm.nih.gov/18254726/ DOI: 10.1042/bj20071373
    tissue_or_cell_type
    Cytosolic quinone-reductase active site

    Melatonin: synthesis, receptors, circadian timing and nutrient interactions (2026-09-17) · lines 500–511

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Kinetics, calorimetry and crystal structures · source_derived_draft · unverified_draft

    ### melatonin-nqo2-menadione-kinetics Against menadione, melatonin showed uncompetitive NQO2 inhibition with Ki about 92 micromolar. Condition category: normal nutrient_topic: Melatonin research collection; topical membership is not evidence of a direct dietary effect. plain_language: The inhibition pattern depends on which reaction participant is varied. organism: Purified human NQO2/QR2 tissue_or_cell_type: Cytosolic quinone-reductase active site experimental_model: Kinetics, calorimetry and crystal structures limitations: NQO2 is the historically named MT3 binding site, not a third MT1/MT2-like GPCR. Micromolar inhibition does not establish the dominant effect at physiological blood concentrations. exposure: Melatonin versus N-methyldihydronicotinamide or menadione in enzyme assays evidence_span: {"source_cache": "artifacts/melatonin-research/18254726.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4b99428e7457cd7b67c75ef01b056609dcdf6d5d36cf1c0e933607e2be485c18", "start_char": 0, "end_char": 1724, "text_sha256": "4b99428e7457cd7b67c75ef01b056609dcdf6d5d36cf1c0e933607e2be485c18"} [melatonin-p18254726] Kinetic, thermodynamic and X-ray structural insights into the interaction of melatonin and analogues with quinone reductase 2. (2008). https://pubmed.ncbi.nlm.nih.gov/18254726/ DOI: 10.1042/bj20071373
    Complete structured claim and evidence

  2. Product analysis identified reduced menadione, rather than its quinone form, as an intermediate in UBIAD1-mediated MK-4 formation.

    Human UBIAD1 prenyltransferase → Menadiol / reduced menadione source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/k2-research/24085302.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a0197882d517aa2bd4d9b2919e72c588383ad183064f1a2bf8f64f5152d28386", "start_char": 0, "end_char": 1653, "text_sha256": "a0197882d517aa2bd4d9b2919e72c588383ad183064f1a2bf8f64f5152d28386"}
    experimental_model
    Stable-isotope cannulation and recombinant-enzyme product analysis
    exposure
    Oral labeled phylloquinone; MS and NMR analysis
    limitations
    Rat tracing defines a precursor route; no exact human conversion fraction or advice to ingest menadione is inferred.
    nutrient_topic
    Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin K2 / menaquinone family
    organism
    Rats and recombinant UBIAD1
    plain_language
    The precursor must also be in the right redox state.
    primary_references
    [k2-p24085302] Menadione (vitamin K3) is a catabolic product of oral phylloquinone (vitamin K1) in the intestine and a circulating precursor of tissue menaquinone-4 (vitamin K2) in rats. (2013). https://pubmed.ncbi.nlm.nih.gov/24085302/ DOI: 10.1074/jbc.m113.477356
    tissue_or_cell_type
    Intestine, circulation and tissue synthesis

    Vitamin K2: menaquinone forms, carboxylation, recycling and nutrient interactions (2026-09-17) · lines 188–199

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Stable-isotope cannulation and recombinant-enzyme product analysis · source_derived_draft · unverified_draft

    ### k2-reduced-precursor Product analysis identified reduced menadione, rather than its quinone form, as an intermediate in UBIAD1-mediated MK-4 formation. Condition category: normal nutrient_topic: Vitamin K2 research collection; topical membership is not evidence of a direct dietary effect. plain_language: The precursor must also be in the right redox state. organism: Rats and recombinant UBIAD1 tissue_or_cell_type: Intestine, circulation and tissue synthesis experimental_model: Stable-isotope cannulation and recombinant-enzyme product analysis limitations: Rat tracing defines a precursor route; no exact human conversion fraction or advice to ingest menadione is inferred. exposure: Oral labeled phylloquinone; MS and NMR analysis evidence_span: {"source_cache": "artifacts/k2-research/24085302.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a0197882d517aa2bd4d9b2919e72c588383ad183064f1a2bf8f64f5152d28386", "start_char": 0, "end_char": 1653, "text_sha256": "a0197882d517aa2bd4d9b2919e72c588383ad183064f1a2bf8f64f5152d28386"} [k2-p24085302] Menadione (vitamin K3) is a catabolic product of oral phylloquinone (vitamin K1) in the intestine and a circulating precursor of tissue menaquinone-4 (vitamin K2) in rats. (2013). https://pubmed.ncbi.nlm.nih.gov/24085302/ DOI: 10.1074/jbc.m113.477356
    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