Component

Human NNMT

Human nicotinamide N-methyltransferase; uses SAM as methyl donor.

5 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 it acts on

  1. At 10–20 micromolar medium methionine, NNMT-overexpressing 769P cells had reduced methylation of several histone lysine marks compared with controls.

    Human NNMT → Histone methylation source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    true
    evidence_span
    {"source_cache": "artifacts/niacin-consumption-sources/nnmt2013.txt", "locator": "Full text, normalized paragraph 35", "start_char": 19327, "end_char": 21089, "file_sha256": "7d88fd656ba772962185234a9bd021e40a9b83f9156db836f723eba06b68acca", "text_sha256": "5b6ea17ec741ecc064f97de9d83d49809db5e62588ffc1164e6e771fc9fc50c3"}
    experimental_model
    Immunoblotting of histone methylation in engineered cells
    exposure
    NNMT overexpression; 10 or 20 micromolar methionine; GFP and inactive NNMT controls
    limitations
    Engineered human cancer-cell culture, not healthy-human niacin repletion. SAM consumption does not establish systemic methyl depletion or a need for folate/B12 supplements. Not every histone mark changed; this does not establish global DNA hypomethylation.
    nutrient_topic
    Niacin research collection; topical membership is not evidence of a direct dietary effect. · Niacin (vitamin B3)
    organism
    Human
    plain_language
    NNMT changed several histone methylation marks in this culture model.
    primary_references
    [b3-cons-nnmt2013] NNMT promotes epigenetic remodeling in cancer by creating a metabolic methylation sink. (2013). https://pubmed.ncbi.nlm.nih.gov/23455543/ DOI: 10.1038/nchembio.1204
    tissue_or_cell_type
    Human 769P renal carcinoma cells

    Niacin: NAD metabolism, deficiency and nutrient interactions (2026-09-17) · lines 803–815

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Immunoblotting of histone methylation in engineered cells · source_derived_draft · unverified_draft

    ### b3-cons-nnmt-histone-methylation At 10–20 micromolar medium methionine, NNMT-overexpressing 769P cells had reduced methylation of several histone lysine marks compared with controls. Condition category: normal nutrient_topic: Niacin research collection; topical membership is not evidence of a direct dietary effect. plain_language: NNMT changed several histone methylation marks in this culture model. organism: Human tissue_or_cell_type: Human 769P renal carcinoma cells experimental_model: Immunoblotting of histone methylation in engineered cells limitations: Engineered human cancer-cell culture, not healthy-human niacin repletion. SAM consumption does not establish systemic methyl depletion or a need for folate/B12 supplements. Not every histone mark changed; this does not establish global DNA hypomethylation. exposure: NNMT overexpression; 10 or 20 micromolar methionine; GFP and inactive NNMT controls cross_nutrient: true evidence_span: {"source_cache": "artifacts/niacin-consumption-sources/nnmt2013.txt", "locator": "Full text, normalized paragraph 35", "start_char": 19327, "end_char": 21089, "file_sha256": "7d88fd656ba772962185234a9bd021e40a9b83f9156db836f723eba06b68acca", "text_sha256": "5b6ea17ec741ecc064f97de9d83d49809db5e62588ffc1164e6e771fc9fc50c3"} [b3-cons-nnmt2013] NNMT promotes epigenetic remodeling in cancer by creating a metabolic methylation sink. (2013). https://pubmed.ncbi.nlm.nih.gov/23455543/ DOI: 10.1038/nchembio.1204
    Complete structured claim and evidence

  2. NNMT transfers a methyl group from SAM to nicotinamide, yielding N1-methylnicotinamide and S-adenosylhomocysteine.

    Human NNMT → N1-Methylnicotinamide source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    true
    evidence_span
    {"source_cache": "artifacts/niacin-consumption-sources/nnmt2013.txt", "locator": "Full text, normalized paragraph 8", "start_char": 2396, "end_char": 4508, "file_sha256": "7d88fd656ba772962185234a9bd021e40a9b83f9156db836f723eba06b68acca", "text_sha256": "fc5cdd48751fa59656f5c16e70c31ab3f36788c265267d7cb57f269bb1848fc6"}
    experimental_model
    Human cancer-cell enzyme activity and metabolomics study
    exposure
    Nicotinamide substrate and NNMT expression/activity comparisons
    limitations
    Engineered human cancer-cell culture, not healthy-human niacin repletion. SAM consumption does not establish systemic methyl depletion or a need for folate/B12 supplements.
    nutrient_topic
    Niacin research collection; topical membership is not evidence of a direct dietary effect. · Niacin (vitamin B3)
    organism
    Human
    plain_language
    Nicotinamide methylation uses a methyl group from SAM.
    primary_references
    [b3-cons-nnmt2013] NNMT promotes epigenetic remodeling in cancer by creating a metabolic methylation sink. (2013). https://pubmed.ncbi.nlm.nih.gov/23455543/ DOI: 10.1038/nchembio.1204
    tissue_or_cell_type
    769P, OVCAR3, MUM2C and comparison cell models

    Niacin: NAD metabolism, deficiency and nutrient interactions (2026-09-17) · lines 747–759

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Human cancer-cell enzyme activity and metabolomics study · source_derived_draft · unverified_draft

    ### b3-cons-nnmt-methyl-transfer NNMT transfers a methyl group from SAM to nicotinamide, yielding N1-methylnicotinamide and S-adenosylhomocysteine. Condition category: normal nutrient_topic: Niacin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Nicotinamide methylation uses a methyl group from SAM. organism: Human tissue_or_cell_type: 769P, OVCAR3, MUM2C and comparison cell models experimental_model: Human cancer-cell enzyme activity and metabolomics study limitations: Engineered human cancer-cell culture, not healthy-human niacin repletion. SAM consumption does not establish systemic methyl depletion or a need for folate/B12 supplements. exposure: Nicotinamide substrate and NNMT expression/activity comparisons cross_nutrient: true evidence_span: {"source_cache": "artifacts/niacin-consumption-sources/nnmt2013.txt", "locator": "Full text, normalized paragraph 8", "start_char": 2396, "end_char": 4508, "file_sha256": "7d88fd656ba772962185234a9bd021e40a9b83f9156db836f723eba06b68acca", "text_sha256": "fc5cdd48751fa59656f5c16e70c31ab3f36788c265267d7cb57f269bb1848fc6"} [b3-cons-nnmt2013] NNMT promotes epigenetic remodeling in cancer by creating a metabolic methylation sink. (2013). https://pubmed.ncbi.nlm.nih.gov/23455543/ DOI: 10.1038/nchembio.1204
    Complete structured claim and evidence

  3. NNMT overexpression raised cellular SAH relative to GFP or inactive-NNMT controls in the tested human cancer-cell models.

    Human NNMT → Cellular S-adenosylhomocysteine concentration source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    true
    evidence_span
    {"source_cache": "artifacts/niacin-consumption-sources/nnmt2013.txt", "locator": "Full text, normalized paragraph 24", "start_char": 12788, "end_char": 14928, "file_sha256": "7d88fd656ba772962185234a9bd021e40a9b83f9156db836f723eba06b68acca", "text_sha256": "760641ee47babbc4c1261afe881ea4baa14ae9032d0538bd467c9957224059f7"}
    experimental_model
    Targeted LC-MS metabolomics
    exposure
    Stable NNMT overexpression; 100 micromolar methionine medium and lower-methionine comparisons
    limitations
    Engineered human cancer-cell culture, not healthy-human niacin repletion. SAM consumption does not establish systemic methyl depletion or a need for folate/B12 supplements.
    nutrient_topic
    Niacin research collection; topical membership is not evidence of a direct dietary effect. · Niacin (vitamin B3)
    organism
    Human
    plain_language
    Extra NNMT activity increased the methyl-transfer coproduct SAH.
    primary_references
    [b3-cons-nnmt2013] NNMT promotes epigenetic remodeling in cancer by creating a metabolic methylation sink. (2013). https://pubmed.ncbi.nlm.nih.gov/23455543/ DOI: 10.1038/nchembio.1204
    tissue_or_cell_type
    769P renal carcinoma; MUM2C and OVCAR3 comparisons

    Niacin: NAD metabolism, deficiency and nutrient interactions (2026-09-17) · lines 761–773

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Targeted LC-MS metabolomics · source_derived_draft · unverified_draft

    ### b3-cons-nnmt-sah-increase NNMT overexpression raised cellular SAH relative to GFP or inactive-NNMT controls in the tested human cancer-cell models. Condition category: normal nutrient_topic: Niacin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Extra NNMT activity increased the methyl-transfer coproduct SAH. organism: Human tissue_or_cell_type: 769P renal carcinoma; MUM2C and OVCAR3 comparisons experimental_model: Targeted LC-MS metabolomics limitations: Engineered human cancer-cell culture, not healthy-human niacin repletion. SAM consumption does not establish systemic methyl depletion or a need for folate/B12 supplements. exposure: Stable NNMT overexpression; 100 micromolar methionine medium and lower-methionine comparisons cross_nutrient: true evidence_span: {"source_cache": "artifacts/niacin-consumption-sources/nnmt2013.txt", "locator": "Full text, normalized paragraph 24", "start_char": 12788, "end_char": 14928, "file_sha256": "7d88fd656ba772962185234a9bd021e40a9b83f9156db836f723eba06b68acca", "text_sha256": "760641ee47babbc4c1261afe881ea4baa14ae9032d0538bd467c9957224059f7"} [b3-cons-nnmt2013] NNMT promotes epigenetic remodeling in cancer by creating a metabolic methylation sink. (2013). https://pubmed.ncbi.nlm.nih.gov/23455543/ DOI: 10.1038/nchembio.1204
    Complete structured claim and evidence

  4. In 769P cells cultured with 10 micromolar methionine, NNMT overexpression significantly lowered SAM relative to control cells.

    Human NNMT → Cellular S-adenosylmethionine concentration source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    true
    evidence_span
    {"source_cache": "artifacts/niacin-consumption-sources/nnmt2013.txt", "locator": "Full text, normalized paragraph 24", "start_char": 12788, "end_char": 14928, "file_sha256": "7d88fd656ba772962185234a9bd021e40a9b83f9156db836f723eba06b68acca", "text_sha256": "760641ee47babbc4c1261afe881ea4baa14ae9032d0538bd467c9957224059f7"}
    experimental_model
    Targeted LC-MS metabolomics
    exposure
    NNMT overexpression versus GFP/inactive Y20A controls in 10 micromolar methionine medium
    limitations
    Engineered human cancer-cell culture, not healthy-human niacin repletion. SAM consumption does not establish systemic methyl depletion or a need for folate/B12 supplements. Low medium methionine is an experimental exposure, not diagnosed human methionine or niacin deficiency.
    nutrient_topic
    Niacin research collection; topical membership is not evidence of a direct dietary effect. · Niacin (vitamin B3)
    organism
    Human
    plain_language
    SAM fell when these NNMT-rich cancer cells were cultured with less methionine.
    primary_references
    [b3-cons-nnmt2013] NNMT promotes epigenetic remodeling in cancer by creating a metabolic methylation sink. (2013). https://pubmed.ncbi.nlm.nih.gov/23455543/ DOI: 10.1038/nchembio.1204
    tissue_or_cell_type
    Human 769P renal carcinoma cells

    Niacin: NAD metabolism, deficiency and nutrient interactions (2026-09-17) · lines 789–801

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Targeted LC-MS metabolomics · source_derived_draft · unverified_draft

    ### b3-cons-nnmt-sam-low-methionine In 769P cells cultured with 10 micromolar methionine, NNMT overexpression significantly lowered SAM relative to control cells. Condition category: normal nutrient_topic: Niacin research collection; topical membership is not evidence of a direct dietary effect. plain_language: SAM fell when these NNMT-rich cancer cells were cultured with less methionine. organism: Human tissue_or_cell_type: Human 769P renal carcinoma cells experimental_model: Targeted LC-MS metabolomics limitations: Engineered human cancer-cell culture, not healthy-human niacin repletion. SAM consumption does not establish systemic methyl depletion or a need for folate/B12 supplements. Low medium methionine is an experimental exposure, not diagnosed human methionine or niacin deficiency. exposure: NNMT overexpression versus GFP/inactive Y20A controls in 10 micromolar methionine medium cross_nutrient: true evidence_span: {"source_cache": "artifacts/niacin-consumption-sources/nnmt2013.txt", "locator": "Full text, normalized paragraph 24", "start_char": 12788, "end_char": 14928, "file_sha256": "7d88fd656ba772962185234a9bd021e40a9b83f9156db836f723eba06b68acca", "text_sha256": "760641ee47babbc4c1261afe881ea4baa14ae9032d0538bd467c9957224059f7"} [b3-cons-nnmt2013] NNMT promotes epigenetic remodeling in cancer by creating a metabolic methylation sink. (2013). https://pubmed.ncbi.nlm.nih.gov/23455543/ DOI: 10.1038/nchembio.1204
    Complete structured claim and evidence

  5. At standard 100 micromolar medium methionine, NNMT overexpression changed SAM by less than 1.5-fold despite increased SAH.

    Human NNMT → Cellular S-adenosylmethionine concentration source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    true
    evidence_span
    {"source_cache": "artifacts/niacin-consumption-sources/nnmt2013.txt", "locator": "Full text, normalized paragraph 24", "start_char": 12788, "end_char": 14928, "file_sha256": "7d88fd656ba772962185234a9bd021e40a9b83f9156db836f723eba06b68acca", "text_sha256": "760641ee47babbc4c1261afe881ea4baa14ae9032d0538bd467c9957224059f7"}
    experimental_model
    Targeted LC-MS metabolomics
    exposure
    100 micromolar methionine culture medium; NNMT overexpression
    limitations
    Engineered human cancer-cell culture, not healthy-human niacin repletion. SAM consumption does not establish systemic methyl depletion or a need for folate/B12 supplements.
    nutrient_topic
    Niacin research collection; topical membership is not evidence of a direct dietary effect. · Niacin (vitamin B3)
    organism
    Human
    plain_language
    A higher methyl-transfer product did not necessarily mean a large fall in SAM.
    primary_references
    [b3-cons-nnmt2013] NNMT promotes epigenetic remodeling in cancer by creating a metabolic methylation sink. (2013). https://pubmed.ncbi.nlm.nih.gov/23455543/ DOI: 10.1038/nchembio.1204
    tissue_or_cell_type
    Human cancer-cell overexpression models

    Niacin: NAD metabolism, deficiency and nutrient interactions (2026-09-17) · lines 775–787

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Targeted LC-MS metabolomics · source_derived_draft · unverified_draft

    ### b3-cons-nnmt-sam-standard At standard 100 micromolar medium methionine, NNMT overexpression changed SAM by less than 1.5-fold despite increased SAH. Condition category: normal nutrient_topic: Niacin research collection; topical membership is not evidence of a direct dietary effect. plain_language: A higher methyl-transfer product did not necessarily mean a large fall in SAM. organism: Human tissue_or_cell_type: Human cancer-cell overexpression models experimental_model: Targeted LC-MS metabolomics limitations: Engineered human cancer-cell culture, not healthy-human niacin repletion. SAM consumption does not establish systemic methyl depletion or a need for folate/B12 supplements. exposure: 100 micromolar methionine culture medium; NNMT overexpression cross_nutrient: true evidence_span: {"source_cache": "artifacts/niacin-consumption-sources/nnmt2013.txt", "locator": "Full text, normalized paragraph 24", "start_char": 12788, "end_char": 14928, "file_sha256": "7d88fd656ba772962185234a9bd021e40a9b83f9156db836f723eba06b68acca", "text_sha256": "760641ee47babbc4c1261afe881ea4baa14ae9032d0538bd467c9957224059f7"} [b3-cons-nnmt2013] NNMT promotes epigenetic remodeling in cancer by creating a metabolic methylation sink. (2013). https://pubmed.ncbi.nlm.nih.gov/23455543/ DOI: 10.1038/nchembio.1204
    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.

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