Component

Thioredoxin reductase catalytic activity

Thioredoxin reductase catalytic activity. 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 it acts on

  1. Recovery of thioredoxin reductase activity over four days paralleled the return of the cells to a normal rate of growth, and the authors conclude that full activity of TrxR1, required for production of deoxyribonucleotides for DNA synthesis, is essential for normal growth of oxygen-challenged cells.

    Thioredoxin reductase catalytic activity → Human lens epithelial cell growth source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    evidence_span
    {"source_cache": "artifacts/hbot-research/15642322.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "e3bc035a17e4e19dd92d4fadb1a79f8e3801619dac24fb91dcf985728afaf995", "start_char": 0, "end_char": 2646, "text_sha256": "e3bc035a17e4e19dd92d4fadb1a79f8e3801619dac24fb91dcf985728afaf995"}
    experimental_model
    Cultured human lens epithelial cells exposed to extreme hyperbaric oxygen with enzyme assays and real-time PCR
    exposure
    99% oxygen at 50 atmospheres for 3 hours, then normal culture for up to 11 days
    limitations
    Fifty atmospheres is an extreme experimental exposure far above therapy, chosen to probe which defences matter. The selenoenzyme result is the informative part; the pressure is not clinically relevant.
    nutrient_topic
    Hyperbaric oxygen research collection; topical membership is not evidence of a direct clinical effect, and a therapeutic exposure is not a dietary intake. · Hyperbaric oxygen therapy
    organism
    Human cells
    plain_language
    The cells could not start dividing again until that enzyme came back.
    primary_references
    [hbot-p15642322] Thioredoxin reductase may be essential for the normal growth of hyperbaric oxygen-treated human lens epithelial cells. (2004). https://pubmed.ncbi.nlm.nih.gov/15642322/ DOI: 10.1016/j.exer.2004.07.001
    tissue_or_cell_type
    Lens epithelium
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Hyperbaric oxygen: the exposure, its reactive species, the signals they carry, and the nutrient-dependent enzymes that handle them (2026-09-19) · lines 400–411

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cultured human lens epithelial cells exposed to extreme hyperbaric oxygen with enzyme assays and real-time PCR · source_derived_draft · unverified_draft

    ### hbot-trxr-growth-requirement Recovery of thioredoxin reductase activity over four days paralleled the return of the cells to a normal rate of growth, and the authors conclude that full activity of TrxR1, required for production of deoxyribonucleotides for DNA synthesis, is essential for normal growth of oxygen-challenged cells. Condition category: machinery_impairment nutrient_topic: Hyperbaric oxygen research collection; topical membership is not evidence of a direct clinical effect, and a therapeutic exposure is not a dietary intake. plain_language: The cells could not start dividing again until that enzyme came back. organism: Human cells tissue_or_cell_type: Lens epithelium experimental_model: Cultured human lens epithelial cells exposed to extreme hyperbaric oxygen with enzyme assays and real-time PCR limitations: Fifty atmospheres is an extreme experimental exposure far above therapy, chosen to probe which defences matter. The selenoenzyme result is the informative part; the pressure is not clinically relevant. exposure: 99% oxygen at 50 atmospheres for 3 hours, then normal culture for up to 11 days evidence_span: {"source_cache": "artifacts/hbot-research/15642322.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "e3bc035a17e4e19dd92d4fadb1a79f8e3801619dac24fb91dcf985728afaf995", "start_char": 0, "end_char": 2646, "text_sha256": "e3bc035a17e4e19dd92d4fadb1a79f8e3801619dac24fb91dcf985728afaf995"} [hbot-p15642322] Thioredoxin reductase may be essential for the normal growth of hyperbaric oxygen-treated human lens epithelial cells. (2004). https://pubmed.ncbi.nlm.nih.gov/15642322/ DOI: 10.1016/j.exer.2004.07.001
    Complete structured claim and evidence

What acts on it

  1. Thioredoxin reductase activity fell by 51% after the 3-hour oxygen exposure, while cellular glutathione and the activities of several other antioxidant enzymes, including glyceraldehyde-3-phosphate dehydrogenase, showed no immediate effect.

    Hyperbaric oxygen therapy → Thioredoxin reductase catalytic activity source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/hbot-research/15642322.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "e3bc035a17e4e19dd92d4fadb1a79f8e3801619dac24fb91dcf985728afaf995", "start_char": 0, "end_char": 2646, "text_sha256": "e3bc035a17e4e19dd92d4fadb1a79f8e3801619dac24fb91dcf985728afaf995"}
    experimental_model
    Cultured human lens epithelial cells exposed to extreme hyperbaric oxygen with enzyme assays and real-time PCR
    exposure
    99% oxygen at 50 atmospheres for 3 hours, then normal culture for up to 11 days
    limitations
    Fifty atmospheres is an extreme experimental exposure far above therapy, chosen to probe which defences matter. The selenoenzyme result is the informative part; the pressure is not clinically relevant.
    nutrient_topic
    Hyperbaric oxygen research collection; topical membership is not evidence of a direct clinical effect, and a therapeutic exposure is not a dietary intake. · Hyperbaric oxygen therapy
    organism
    Human cells
    plain_language
    Of all the defences measured, the selenium enzyme was the one that was knocked down.
    primary_references
    [hbot-p15642322] Thioredoxin reductase may be essential for the normal growth of hyperbaric oxygen-treated human lens epithelial cells. (2004). https://pubmed.ncbi.nlm.nih.gov/15642322/ DOI: 10.1016/j.exer.2004.07.001
    tissue_or_cell_type
    Lens epithelium

    Hyperbaric oxygen: the exposure, its reactive species, the signals they carry, and the nutrient-dependent enzymes that handle them (2026-09-19) · lines 387–398

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cultured human lens epithelial cells exposed to extreme hyperbaric oxygen with enzyme assays and real-time PCR · source_derived_draft · unverified_draft

    ### hbot-trxr-activity-loss Thioredoxin reductase activity fell by 51% after the 3-hour oxygen exposure, while cellular glutathione and the activities of several other antioxidant enzymes, including glyceraldehyde-3-phosphate dehydrogenase, showed no immediate effect. Condition category: normal nutrient_topic: Hyperbaric oxygen research collection; topical membership is not evidence of a direct clinical effect, and a therapeutic exposure is not a dietary intake. plain_language: Of all the defences measured, the selenium enzyme was the one that was knocked down. organism: Human cells tissue_or_cell_type: Lens epithelium experimental_model: Cultured human lens epithelial cells exposed to extreme hyperbaric oxygen with enzyme assays and real-time PCR limitations: Fifty atmospheres is an extreme experimental exposure far above therapy, chosen to probe which defences matter. The selenoenzyme result is the informative part; the pressure is not clinically relevant. exposure: 99% oxygen at 50 atmospheres for 3 hours, then normal culture for up to 11 days evidence_span: {"source_cache": "artifacts/hbot-research/15642322.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "e3bc035a17e4e19dd92d4fadb1a79f8e3801619dac24fb91dcf985728afaf995", "start_char": 0, "end_char": 2646, "text_sha256": "e3bc035a17e4e19dd92d4fadb1a79f8e3801619dac24fb91dcf985728afaf995"} [hbot-p15642322] Thioredoxin reductase may be essential for the normal growth of hyperbaric oxygen-treated human lens epithelial cells. (2004). https://pubmed.ncbi.nlm.nih.gov/15642322/ DOI: 10.1016/j.exer.2004.07.001
    Complete structured claim and evidence

  2. The SeCys498 to Cys enzyme retained catalytic activity in thioredoxin reduction with a 100-fold lower kcat and a 10-fold lower Km, and its pH optimum shifted from 7 to 9, strongly suggesting involvement of the low-pKa selenol in the mechanism.

    Recombinant rat thioredoxin reductase with SeCys498 replaced by cysteine → Thioredoxin reductase catalytic activity source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    nutrient_deficiency Imported condition classification; unverified.
    evidence_span
    {"source_cache": "artifacts/hbot-research/10849437.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "13fe79ebefbddac9a76f4cae2e0f1aede8d648b6568adca72f0b0a550e66bc90", "start_char": 0, "end_char": 1374, "text_sha256": "13fe79ebefbddac9a76f4cae2e0f1aede8d648b6568adca72f0b0a550e66bc90"}
    experimental_model
    Recombinant rat thioredoxin reductase with selenocysteine mutations expressed in E. coli
    exposure
    SeCys498 replaced by cysteine or serine, and a truncated protein lacking the C-terminal SeCys-Gly dipeptide
    limitations
    The truncated construct is described by the authors as the form expected in selenium deficiency, which is what links this enzyme chemistry to nutrient supply. It remains a recombinant model, not a measurement in a selenium-deficient animal.
    nutrient_topic
    Hyperbaric oxygen research collection; topical membership is not evidence of a direct clinical effect, and a therapeutic exposure is not a dietary intake. · Hyperbaric oxygen therapy
    organism
    Rat enzyme in a bacterial expression host
    plain_language
    Swapping selenium for sulphur leaves an enzyme that barely works and only in the wrong conditions.
    primary_references
    [hbot-p10849437] Essential role of selenium in the catalytic activities of mammalian thioredoxin reductase revealed by characterization of recombinant enzymes with selenocysteine mutations. (2000). https://pubmed.ncbi.nlm.nih.gov/10849437/ DOI: 10.1074/jbc.m000690200
    tissue_or_cell_type
    Purified enzyme
    trigger_kind
    nutrient_deficiency Imported condition classification; unverified.

    Hyperbaric oxygen: the exposure, its reactive species, the signals they carry, and the nutrient-dependent enzymes that handle them (2026-09-19) · lines 465–476

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Recombinant rat thioredoxin reductase with selenocysteine mutations expressed in E. coli · source_derived_draft · unverified_draft

    ### hbot-trxr-secys-mutant-activity The SeCys498 to Cys enzyme retained catalytic activity in thioredoxin reduction with a 100-fold lower kcat and a 10-fold lower Km, and its pH optimum shifted from 7 to 9, strongly suggesting involvement of the low-pKa selenol in the mechanism. Condition category: nutrient_deficiency nutrient_topic: Hyperbaric oxygen research collection; topical membership is not evidence of a direct clinical effect, and a therapeutic exposure is not a dietary intake. plain_language: Swapping selenium for sulphur leaves an enzyme that barely works and only in the wrong conditions. organism: Rat enzyme in a bacterial expression host tissue_or_cell_type: Purified enzyme experimental_model: Recombinant rat thioredoxin reductase with selenocysteine mutations expressed in E. coli limitations: The truncated construct is described by the authors as the form expected in selenium deficiency, which is what links this enzyme chemistry to nutrient supply. It remains a recombinant model, not a measurement in a selenium-deficient animal. exposure: SeCys498 replaced by cysteine or serine, and a truncated protein lacking the C-terminal SeCys-Gly dipeptide evidence_span: {"source_cache": "artifacts/hbot-research/10849437.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "13fe79ebefbddac9a76f4cae2e0f1aede8d648b6568adca72f0b0a550e66bc90", "start_char": 0, "end_char": 1374, "text_sha256": "13fe79ebefbddac9a76f4cae2e0f1aede8d648b6568adca72f0b0a550e66bc90"} [hbot-p10849437] Essential role of selenium in the catalytic activities of mammalian thioredoxin reductase revealed by characterization of recombinant enzymes with selenocysteine mutations. (2000). https://pubmed.ncbi.nlm.nih.gov/10849437/ DOI: 10.1074/jbc.m000690200
    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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