Component

hERG / KCNH2

hERG / KCNH2; interpretation depends on linked experimental context.

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 acts on it

  1. Berberine blocked hERG current, with IC50 about 3.1 micromolar in HEK293 cells and 80 micromolar in oocytes.

    Berberine → hERG / KCNH2 source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/berberine-research/16424781.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "45057bbc2da5981b23041d50a91a8e0adacfc150adf66d23daac0402f8ead682", "start_char": 0, "end_char": 1322, "text_sha256": "45057bbc2da5981b23041d50a91a8e0adacfc150adf66d23daac0402f8ead682"}
    experimental_model
    Patch clamp and site-directed mutagenesis
    exposure
    Berberine concentration-response; hERG mutations
    limitations
    Different expression systems had markedly different IC50 values. Channel inhibition is a hazard mechanism, not an incidence estimate for arrhythmia in supplement users.
    nutrient_topic
    Berberine research collection; topical membership is not evidence of a direct dietary effect. · Berberine
    organism
    Human hERG expressed in HEK293 cells and Xenopus oocytes
    plain_language
    A potassium channel needed for cardiac repolarization is a separate safety-related target.
    primary_references
    [berberine-p16424781] Block of HERG channels by berberine: mechanisms of voltage- and state-dependence probed with site-directed mutant channels. (2006). https://pubmed.ncbi.nlm.nih.gov/16424781/ DOI: 10.1097/01.fjc.0000191564.52242.00
    tissue_or_cell_type
    Cardiac potassium-channel model

    Berberine: metabolism, nutrient connections and drug interactions (2026-09-17) · lines 610–621

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Patch clamp and site-directed mutagenesis · source_derived_draft · unverified_draft

    ### berberine-herg-block Berberine blocked hERG current, with IC50 about 3.1 micromolar in HEK293 cells and 80 micromolar in oocytes. Condition category: normal nutrient_topic: Berberine research collection; topical membership is not evidence of a direct dietary effect. plain_language: A potassium channel needed for cardiac repolarization is a separate safety-related target. organism: Human hERG expressed in HEK293 cells and Xenopus oocytes tissue_or_cell_type: Cardiac potassium-channel model experimental_model: Patch clamp and site-directed mutagenesis limitations: Different expression systems had markedly different IC50 values. Channel inhibition is a hazard mechanism, not an incidence estimate for arrhythmia in supplement users. exposure: Berberine concentration-response; hERG mutations evidence_span: {"source_cache": "artifacts/berberine-research/16424781.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "45057bbc2da5981b23041d50a91a8e0adacfc150adf66d23daac0402f8ead682", "start_char": 0, "end_char": 1322, "text_sha256": "45057bbc2da5981b23041d50a91a8e0adacfc150adf66d23daac0402f8ead682"} [berberine-p16424781] Block of HERG channels by berberine: mechanisms of voltage- and state-dependence probed with site-directed mutant channels. (2006). https://pubmed.ncbi.nlm.nih.gov/16424781/ DOI: 10.1097/01.fjc.0000191564.52242.00
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. Four weeks of 0.1% versus 0.62% dietary K produced hypokalemia, reduced ventricular IKr and prolonged corrected QT in rabbits.

    Potassium → Cardiac rapidly activating delayed rectifier potassium current source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    nutrient_deficiency Imported condition classification; unverified.
    experimental_model
    Rabbit dietary experiment, four weeks.
    limitations
    Animal dietary finding does not establish human intake targets or a sole QT mechanism.
    nutrient_topic
    Potassium research collection; topical membership is not evidence of a direct dietary effect. · Potassium
    organism
    Rabbit
    plain_language
    Sustained dietary restriction affected a cardiac recovery current.
    primary_references
    [guo-2009-herg] Extracellular K+ concentration controls cell surface density of IKr in rabbit hearts and of the HERG channel in human cell lines (2009). https://www.jci.org/articles/view/39027 DOI: 10.1172/JCI39027
    tissue_or_cell_type
    Ventricular myocardium
    trigger_kind
    nutrient_deficiency Imported condition classification; unverified.

    Potassium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 704–713

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Rabbit dietary experiment, four weeks. · source_derived_draft · unverified_draft

    ### k-diet-rabbit-ikr Four weeks of 0.1% versus 0.62% dietary K produced hypokalemia, reduced ventricular IKr and prolonged corrected QT in rabbits. Condition category: nutrient_deficiency nutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect. plain_language: Sustained dietary restriction affected a cardiac recovery current. organism: Rabbit tissue_or_cell_type: Ventricular myocardium experimental_model: Rabbit dietary experiment, four weeks. limitations: Animal dietary finding does not establish human intake targets or a sole QT mechanism. [guo-2009-herg] Extracellular K+ concentration controls cell surface density of IKr in rabbit hearts and of the HERG channel in human cell lines (2009). https://www.jci.org/articles/view/39027 DOI: 10.1172/JCI39027
    Complete structured claim and evidence

  2. Low extracellular K accelerated hERG internalization and degradation; 0 versus 5 mM exposure strongly reduced mature surface channels.

    Extracellular potassium concentration → Cell-surface hERG abundance source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    nutrient_deficiency Imported condition classification; unverified.
    experimental_model
    Transfected HEK293 cells, 6-12-hour low-K exposures.
    limitations
    Zero-K culture is more extreme than ordinary hypokalemia.
    nutrient_topic
    Potassium research collection; topical membership is not evidence of a direct dietary effect. · Potassium
    organism
    Human protein in HEK293 cells
    plain_language
    Potassium outside the cell helped retain a cardiac repolarizing channel.
    primary_references
    [guo-2009-herg] Extracellular K+ concentration controls cell surface density of IKr in rabbit hearts and of the HERG channel in human cell lines (2009). https://www.jci.org/articles/view/39027 DOI: 10.1172/JCI39027
    tissue_or_cell_type
    Heterologous culture
    trigger_kind
    nutrient_deficiency Imported condition classification; unverified.

    Potassium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 693–702

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Transfected HEK293 cells, 6-12-hour low-K exposures. · source_derived_draft · unverified_draft

    ### k-low-herg-turnover Low extracellular K accelerated hERG internalization and degradation; 0 versus 5 mM exposure strongly reduced mature surface channels. Condition category: nutrient_deficiency nutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect. plain_language: Potassium outside the cell helped retain a cardiac repolarizing channel. organism: Human protein in HEK293 cells tissue_or_cell_type: Heterologous culture experimental_model: Transfected HEK293 cells, 6-12-hour low-K exposures. limitations: Zero-K culture is more extreme than ordinary hypokalemia. [guo-2009-herg] Extracellular K+ concentration controls cell surface density of IKr in rabbit hearts and of the HERG channel in human cell lines (2009). https://www.jci.org/articles/view/39027 DOI: 10.1172/JCI39027
    Complete structured claim and evidence

  3. Berberine reduced hERG cell-surface abundance through mechanisms involving caveolin-1 and hERG S6 residues.

    Berberine → Cell-surface hERG abundance source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/berberine-research/26543354.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "56eb3a544eb8700c50931e8bbeb16a24786259d3fb9feebb0b2cbe9e81f02734", "start_char": 0, "end_char": 1453, "text_sha256": "56eb3a544eb8700c50931e8bbeb16a24786259d3fb9feebb0b2cbe9e81f02734"}
    experimental_model
    Cell-surface protein regulation and mutagenesis
    exposure
    Berberine exposure and caveolin-1 knockdown
    limitations
    Channel abundance and direct current block are distinct mechanisms. Experimental rescue compounds are not clinical antidote recommendations.
    nutrient_topic
    Berberine research collection; topical membership is not evidence of a direct dietary effect. · Berberine
    organism
    Human hERG-expressing HEK293 cells
    plain_language
    Longer exposure can reduce the number of channels as well as block their current.
    primary_references
    [berberine-p26543354] Mechanism and pharmacological rescue of berberine-induced hERG channel deficiency. (2015). https://pubmed.ncbi.nlm.nih.gov/26543354/ DOI: 10.2147/dddt.s91561
    tissue_or_cell_type
    hERG membrane stability

    Berberine: metabolism, nutrient connections and drug interactions (2026-09-17) · lines 623–634

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cell-surface protein regulation and mutagenesis · source_derived_draft · unverified_draft

    ### berberine-herg-abundance Berberine reduced hERG cell-surface abundance through mechanisms involving caveolin-1 and hERG S6 residues. Condition category: normal nutrient_topic: Berberine research collection; topical membership is not evidence of a direct dietary effect. plain_language: Longer exposure can reduce the number of channels as well as block their current. organism: Human hERG-expressing HEK293 cells tissue_or_cell_type: hERG membrane stability experimental_model: Cell-surface protein regulation and mutagenesis limitations: Channel abundance and direct current block are distinct mechanisms. Experimental rescue compounds are not clinical antidote recommendations. exposure: Berberine exposure and caveolin-1 knockdown evidence_span: {"source_cache": "artifacts/berberine-research/26543354.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "56eb3a544eb8700c50931e8bbeb16a24786259d3fb9feebb0b2cbe9e81f02734", "start_char": 0, "end_char": 1453, "text_sha256": "56eb3a544eb8700c50931e8bbeb16a24786259d3fb9feebb0b2cbe9e81f02734"} [berberine-p26543354] Mechanism and pharmacological rescue of berberine-induced hERG channel deficiency. (2015). https://pubmed.ncbi.nlm.nih.gov/26543354/ DOI: 10.2147/dddt.s91561
    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