Human cathepsin B: molecular mechanisms & dependencies

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.

Human evidence only

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

Where it participates (unsigned role)

Human thyroid lysosomal extracts cleaved radioiodinated rabbit TG into discrete iodine-bearing peptides before iodoamino-acid release.
Rabbit thyroglobulin → Thyroglobulin iodopeptide formation source_derived_draftungraded
Experimental context and source evidence
cross_nutrient
false
evidence_span
{"source_cache": "artifacts/iodine-synthesis-sources/1903699.json", "json_field": "abstractText", "text_sha256": "2fecda8478b67ba815425948ac7198157a2d0e8fe18381b9bf3a9fd0e5190410", "text_characters": 2209, "note": "Exact publisher passage retained in the cited local source cache; locator and digest supplied here."}
experimental_model
In-vivo-radioiodinated rabbit TG incubated with human thyroid lysosomal extracts and protease inhibitors
exposure
Rabbit [125I]TG with human thyroid lysosomal extracts: 20–45 minutes for peptides; 8 and 24 hours for iodoamino-acid release.
limitations
Mixed-species cell-free system; precursor proteolysis is not equivalent to circulating hormone secretion.
nutrient_topic
Iodine research collection; topical membership is not evidence of a direct dietary effect. · Iodine
organism
Oryctolagus cuniculus substrate; Homo sapiens lysosomal extracts
plain_language
Thyroglobulin is first cut into smaller hormone-containing fragments.
primary_references
[iodine-syn-lysosome1991] Proteolytic processing of thyroglobulin by extracts of thyroid lysosomes. (1991). https://pubmed.ncbi.nlm.nih.gov/1903699/ DOI: 10.1210/endo-128-6-3073
tissue_or_cell_type
Human thyroid lysosomal extracts
Iodine: thyroid hormone production, deficiency, excess and nutrient interactions (2026-09-17) · lines 660–672
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · In-vivo-radioiodinated rabbit TG incubated with human thyroid lysosomal extracts and protease inhibitors · source_derived_draft · unverified_draft
### iodine-syn-lysosomal-fragments Human thyroid lysosomal extracts cleaved radioiodinated rabbit TG into discrete iodine-bearing peptides before iodoamino-acid release. Condition category: normal nutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect. plain_language: Thyroglobulin is first cut into smaller hormone-containing fragments. organism: Oryctolagus cuniculus substrate; Homo sapiens lysosomal extracts tissue_or_cell_type: Human thyroid lysosomal extracts experimental_model: In-vivo-radioiodinated rabbit TG incubated with human thyroid lysosomal extracts and protease inhibitors limitations: Mixed-species cell-free system; precursor proteolysis is not equivalent to circulating hormone secretion. exposure: Rabbit [125I]TG with human thyroid lysosomal extracts: 20–45 minutes for peptides; 8 and 24 hours for iodoamino-acid release. cross_nutrient: false evidence_span: {"source_cache": "artifacts/iodine-synthesis-sources/1903699.json", "json_field": "abstractText", "text_sha256": "2fecda8478b67ba815425948ac7198157a2d0e8fe18381b9bf3a9fd0e5190410", "text_characters": 2209, "note": "Exact publisher passage retained in the cited local source cache; locator and digest supplied here."} [iodine-syn-lysosome1991] Proteolytic processing of thyroglobulin by extracts of thyroid lysosomes. (1991). https://pubmed.ncbi.nlm.nih.gov/1903699/ DOI: 10.1210/endo-128-6-3073
Complete structured claim and evidence
Combined inhibition of cathepsins B, D and L reduced long-incubation iodoamino-acid release from radioiodinated rabbit TG by 80–90%.
Experimental cathepsin B/D/L inhibitor combination → Lysosomal iodoamino acid release source_derived_draftungraded
Experimental context and source evidence
cross_nutrient
false
evidence_span
{"source_cache": "artifacts/iodine-synthesis-sources/1903699.json", "json_field": "abstractText", "text_sha256": "2fecda8478b67ba815425948ac7198157a2d0e8fe18381b9bf3a9fd0e5190410", "text_characters": 2209, "note": "Exact publisher passage retained in the cited local source cache; locator and digest supplied here."}
experimental_model
In-vivo-radioiodinated rabbit TG incubated with human thyroid lysosomal extracts and protease inhibitors
exposure
Rabbit [125I]TG with human thyroid lysosomal extracts: 20–45 minutes for peptides; 8 and 24 hours for iodoamino-acid release. Combined protease inhibition.
limitations
Iodoamino-acid endpoint includes iodothyronines and iodotyrosines; do not assign the percentage specifically to T4.
nutrient_topic
Iodine research collection; topical membership is not evidence of a direct dietary effect. · Iodine
organism
Oryctolagus cuniculus substrate; Homo sapiens enzymes
plain_language
Blocking these proteases greatly reduced release of iodinated amino acids from TG.
primary_references
[iodine-syn-lysosome1991] Proteolytic processing of thyroglobulin by extracts of thyroid lysosomes. (1991). https://pubmed.ncbi.nlm.nih.gov/1903699/ DOI: 10.1210/endo-128-6-3073
tissue_or_cell_type
Human thyroid lysosomal extracts
Iodine: thyroid hormone production, deficiency, excess and nutrient interactions (2026-09-17) · lines 674–686
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · In-vivo-radioiodinated rabbit TG incubated with human thyroid lysosomal extracts and protease inhibitors · source_derived_draft · unverified_draft
### iodine-syn-lysosomal-inhibition Combined inhibition of cathepsins B, D and L reduced long-incubation iodoamino-acid release from radioiodinated rabbit TG by 80–90%. Condition category: normal nutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect. plain_language: Blocking these proteases greatly reduced release of iodinated amino acids from TG. organism: Oryctolagus cuniculus substrate; Homo sapiens enzymes tissue_or_cell_type: Human thyroid lysosomal extracts experimental_model: In-vivo-radioiodinated rabbit TG incubated with human thyroid lysosomal extracts and protease inhibitors limitations: Iodoamino-acid endpoint includes iodothyronines and iodotyrosines; do not assign the percentage specifically to T4. exposure: Rabbit [125I]TG with human thyroid lysosomal extracts: 20–45 minutes for peptides; 8 and 24 hours for iodoamino-acid release. Combined protease inhibition. cross_nutrient: false evidence_span: {"source_cache": "artifacts/iodine-synthesis-sources/1903699.json", "json_field": "abstractText", "text_sha256": "2fecda8478b67ba815425948ac7198157a2d0e8fe18381b9bf3a9fd0e5190410", "text_characters": 2209, "note": "Exact publisher passage retained in the cited local source cache; locator and digest supplied here."} [iodine-syn-lysosome1991] Proteolytic processing of thyroglobulin by extracts of thyroid lysosomes. (1991). https://pubmed.ncbi.nlm.nih.gov/1903699/ DOI: 10.1210/endo-128-6-3073
Complete structured claim and evidence

The events it takes part in

A mechanism often involves more than two components. These are the full events, with every participant and its role.

Situations it appears in

Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.

In the sources

Preserved passages that mention this component, quoted exactly. Open one to read it in context.

Open hypotheses

Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.

This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.

Human cathepsin B