Component

Theophylline

Theophylline

4 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. Theophylline inhibited purified human PDXK, with Ki 50 micromolar, and occupied its vitamin-substrate site.

    Theophylline → Pyridoxal kinase / PDXK source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    experimental_model
    Purified human PDXK; crystallography and inhibition kinetics
    exposure
    Purified-enzyme inhibition series; 2.1 angstrom crystal structure.
    limitations
    Other preparations yielded different Ki values; this is assay context, not a nutritional threshold.
    nutrient_topic
    Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B6
    organism
    Homo sapiens
    plain_language
    This drug can interfere with B6 activation in an enzyme assay.
    primary_references
    [gandhi-2012-pdxk-inhibitors] Crystal Structures of Human Pyridoxal Kinase in Complex with the Neurotoxins, Ginkgotoxin and Theophylline: Insights into Pyridoxal Kinase Inhibition (2012). https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0040954 DOI: 10.1371/journal.pone.0040954
    tissue_or_cell_type
    Purified recombinant protein; no intact tissue
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Vitamin B6: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1220–1230

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified human PDXK; crystallography and inhibition kinetics · source_derived_draft · unverified_draft

    ### b6-neuro-theophylline-pdxk Theophylline inhibited purified human PDXK, with Ki 50 micromolar, and occupied its vitamin-substrate site. Condition category: machinery_impairment nutrient_topic: Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect. plain_language: This drug can interfere with B6 activation in an enzyme assay. organism: Homo sapiens tissue_or_cell_type: Purified recombinant protein; no intact tissue experimental_model: Purified human PDXK; crystallography and inhibition kinetics limitations: Other preparations yielded different Ki values; this is assay context, not a nutritional threshold. exposure: Purified-enzyme inhibition series; 2.1 angstrom crystal structure. [gandhi-2012-pdxk-inhibitors] Crystal Structures of Human Pyridoxal Kinase in Complex with the Neurotoxins, Ginkgotoxin and Theophylline: Insights into Pyridoxal Kinase Inhibition (2012). https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0040954 DOI: 10.1371/journal.pone.0040954
    Complete structured claim and evidence

What acts on it

  1. CYP1A2 catalyzed theophylline demethylation and hydroxylation, with high affinity and the highest tested intrinsic clearance to dimethyluric acid.

    Human cytochrome P450 1A2 → Theophylline source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/dim-research/7619675.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "0697fc53b8afe8bb59065fc098e9965c7c230ad77823bea7638cd3b8049b04fb", "start_char": 0, "end_char": 1842, "text_sha256": "0697fc53b8afe8bb59065fc098e9965c7c230ad77823bea7638cd3b8049b04fb"}
    experimental_model
    Recombinant human enzyme kinetics
    exposure
    Multiple substrate concentrations
    limitations
    Substrate concentration changed relative contributions. Not a DIM-theophylline study or an individual dosing rule.
    nutrient_topic
    Diindolylmethane (DIM) research collection; topical membership is not evidence of a direct dietary effect. · 3,3'-Diindolylmethane / DIM
    organism
    Human CYP isoforms expressed in lymphoblastoid cells
    plain_language
    Theophylline is a relevant substrate to investigate, but DIM-induced concentration changes were not measured.
    primary_references
    [dim-p7619675] Metabolism of theophylline by cDNA-expressed human cytochromes P-450. (1995). https://pubmed.ncbi.nlm.nih.gov/7619675/ DOI: 10.1111/j.1365-2125.1995.tb04455.x
    tissue_or_cell_type
    Theophylline metabolism

    Diindolylmethane (DIM): formation, receptor signaling, metabolism and drug interactions (2026-09-17) · lines 766–777

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Recombinant human enzyme kinetics · source_derived_draft · unverified_draft

    ### dim-theophylline-1a2 CYP1A2 catalyzed theophylline demethylation and hydroxylation, with high affinity and the highest tested intrinsic clearance to dimethyluric acid. Condition category: normal nutrient_topic: Diindolylmethane (DIM) research collection; topical membership is not evidence of a direct dietary effect. plain_language: Theophylline is a relevant substrate to investigate, but DIM-induced concentration changes were not measured. organism: Human CYP isoforms expressed in lymphoblastoid cells tissue_or_cell_type: Theophylline metabolism experimental_model: Recombinant human enzyme kinetics limitations: Substrate concentration changed relative contributions. Not a DIM-theophylline study or an individual dosing rule. exposure: Multiple substrate concentrations evidence_span: {"source_cache": "artifacts/dim-research/7619675.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "0697fc53b8afe8bb59065fc098e9965c7c230ad77823bea7638cd3b8049b04fb", "start_char": 0, "end_char": 1842, "text_sha256": "0697fc53b8afe8bb59065fc098e9965c7c230ad77823bea7638cd3b8049b04fb"} [dim-p7619675] Metabolism of theophylline by cDNA-expressed human cytochromes P-450. (1995). https://pubmed.ncbi.nlm.nih.gov/7619675/ DOI: 10.1111/j.1365-2125.1995.tb04455.x
    Complete structured claim and evidence

  2. Caffeine N7-demethylation produced the specified dimethylxanthine; fluvoxamine reduced its formation clearance.

    Caffeine → Theophylline source_derived_draftungraded
    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Human caffeine/fluvoxamine crossover and metabolite measurements; eight healthy volunteers.
    limitations
    CYP1A2 is the principal demethylating route; minor routes and individual clearance vary.
    nutrient_topic
    Caffeine collection; salts, coffee, species and coexposure contexts retain their identities. · Caffeine
    plain_language
    Caffeine produces a distinct metabolite that needs its own record.
    primary_references
    A fluvoxamine-caffeine interaction study. · 1996 · https://pubmed.ncbi.nlm.nih.gov/8807660/ · DOI 10.1097/00008571-199606000-00003

    Caffeine: receptors, metabolism, nutrient interactions, adaptation and discovery questions (2026-09-18) · lines 188–194

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Human caffeine/fluvoxamine crossover and metabolite measurements; eight healthy volunteers. · source_derived_draft · unverified_draft

    ## caf-met-tp Caffeine produces a distinct metabolite that needs its own record. Caffeine N7-demethylation produced the specified dimethylxanthine; fluvoxamine reduced its formation clearance. Model: Human caffeine/fluvoxamine crossover and metabolite measurements; eight healthy volunteers. Limitations: CYP1A2 is the principal demethylating route; minor routes and individual clearance vary. Evidence access: Primary abstract A fluvoxamine-caffeine interaction study. · 1996 · https://pubmed.ncbi.nlm.nih.gov/8807660/ · DOI 10.1097/00008571-199606000-00003
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. Dose-normalized serum caffeine rose between first and third trimester in a 59-woman study; theophylline concentrations also rose.

    Caffeine → Plasma caffeine exposure source_derived_draftungraded
    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Women sampled once during a trimester, within one hour of a beverage containing 30–95 mg caffeine.
    limitations
    Sparse, between-person sampling; not full individual clearance curves or evidence establishing fetal safety.
    nutrient_topic
    Caffeine collection; salts, coffee, species and coexposure contexts retain their identities. · Caffeine
    plain_language
    Pregnancy changed caffeine and metabolite exposure.
    primary_references
    Pregnancy-induced changes in the pharmacokinetics of caffeine and its metabolites. · 2016 · https://pubmed.ncbi.nlm.nih.gov/26358647/ · DOI 10.1002/jcph.632

    Caffeine: receptors, metabolism, nutrient interactions, adaptation and discovery questions (2026-09-18) · lines 260–266

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Women sampled once during a trimester, within one hour of a beverage containing 30–95 mg caffeine. · source_derived_draft · unverified_draft

    ## caf-pregnancy Pregnancy changed caffeine and metabolite exposure. Dose-normalized serum caffeine rose between first and third trimester in a 59-woman study; theophylline concentrations also rose. Model: Women sampled once during a trimester, within one hour of a beverage containing 30–95 mg caffeine. Limitations: Sparse, between-person sampling; not full individual clearance curves or evidence establishing fetal safety. Evidence access: Primary abstract Pregnancy-induced changes in the pharmacokinetics of caffeine and its metabolites. · 2016 · https://pubmed.ncbi.nlm.nih.gov/26358647/ · DOI 10.1002/jcph.632
    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