{"id":"20801c6c-5c92-5083-8056-2584a3155284","stable_key":"dff9f743-3766-5f20-a71e-d6d2bd5bfb6f:va-zinc-deficiency-retinal-oxidation-increase","predicate":"deficiency_increases","statement":"The same zinc-deficient rats showed increased retinal oxidase activity, with no detected REH/ARAT activity changes.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"4e73eb9e-0d5a-550a-89d9-f78ccb3a838c","mechanism_event_label":"Vitamin A processing did not simply stop at every step.","subject":{"id":"0429f0ff-c033-514b-9a4f-6f0f83268095","slug":"zinc","display_name":"Zinc","entity_type_key":"nutrient_element"},"object":{"id":"dcd9aada-258d-5855-a5fb-591a177eb5a5","slug":"hepatic-retinal-oxidase-activity","display_name":"Hepatic retinal oxidase activity","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"4e73eb9e-0d5a-550a-89d9-f78ccb3a838c","stable_key":"dff9f743-3766-5f20-a71e-d6d2bd5bfb6f:va-zinc-deficiency-retinal-oxidation-increase-event","event_type":"biochemical_relationship","label":"Vitamin A processing did not simply stop at every step.","description":"The same zinc-deficient rats showed increased retinal oxidase activity, with no detected REH/ARAT activity changes.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"194eccf2-c7a5-52a6-a0c6-1c1f6d0f3a3e","slug":"all-trans-retinal","display_name":"All-trans-retinal","entity_type_key":"small_molecule"},"role":"assay_substrate","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"0429f0ff-c033-514b-9a4f-6f0f83268095","slug":"zinc","display_name":"Zinc","entity_type_key":"nutrient_element"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"dcd9aada-258d-5855-a5fb-591a177eb5a5","slug":"hepatic-retinal-oxidase-activity","display_name":"Hepatic retinal oxidase activity","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"experimental_model","value_text":"Same hepatic activity assays.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Activity is not whole-body flux or proof of a direct zinc-binding requirement.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin A research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-a","display_name":"Vitamin A","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Rattus norvegicus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Vitamin A processing did not simply stop at every step.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[va-kim1988] Effect of zinc deficiency on hepatic enzymes regulating vitamin A status (1988). https://pubmed.ncbi.nlm.nih.gov/3404291/ DOI: 10.1093/jn/118.8.995","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Liver","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"4c6f6000-59f2-5493-8876-f81b90bb30f9","evidence_kind":"source_excerpt","locator":"Lines 1531-1540","start_line":1531,"end_line":1540,"excerpt":"### va-zinc-deficiency-retinal-oxidation-increase\nThe same zinc-deficient rats showed increased retinal oxidase activity, with no detected REH/ARAT activity changes.\nCondition category: nutrient_deficiency\nnutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Vitamin A processing did not simply stop at every step.\norganism: Rattus norvegicus\ntissue_or_cell_type: Liver\nexperimental_model: Same hepatic activity assays.\nlimitations: Activity is not whole-body flux or proof of a direct zinc-binding requirement.\n[va-kim1988] Effect of zinc deficiency on hepatic enzymes regulating vitamin A status (1988). https://pubmed.ncbi.nlm.nih.gov/3404291/ DOI: 10.1093/jn/118.8.995","model_system":"Same hepatic activity assays.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [va-kim1988] Effect of zinc deficiency on hepatic enzymes regulating vitamin A status (1988). https://pubmed.ncbi.nlm.nih.gov/3404291/ DOI: 10.1093/jn/118.8.995","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"0c5474e2-be48-547b-b287-9c07a59c9ff1","stable_key":"import-dff9f743-3766-5f20-a71e-d6d2bd5bfb6f","title":"Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"b217224b262abbd77d6a0c8c9beefff9c022fae4d31e2a5273915d769b9a6546","revision_id":"61008909-871f-575c-b5e2-21542689ea3c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}