{"id":"d4ecc425-50cf-5566-9234-12f7bed7c6a3","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:thiamine-def-microglial-iron-accumulation","predicate":"antagonist-assisted-depletion-increases-regional-content-of","statement":"Iron accumulated in microglia of vulnerable mouse regions from day 10; rat iron-laden microglia often clustered near vessels.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"82900300-1325-57eb-accf-e11974a3b8d6","mechanism_event_label":"Severe depletion changed where iron was retained in the brain.","subject":{"id":"36b7c3eb-068b-500f-af1c-078829df1ecc","slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"},"object":{"id":"89bcaf42-b4ab-5760-8c2e-44eace10cee0","slug":"iron","display_name":"Iron","entity_type_key":"nutrient_element"},"evidence_count":1,"mechanism_event":{"id":"82900300-1325-57eb-accf-e11974a3b8d6","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:thiamine-def-microglial-iron-accumulation-event","event_type":"observed_intervention","label":"Severe depletion changed where iron was retained in the brain.","description":"Iron accumulated in microglia of vulnerable mouse regions from day 10; rat iron-laden microglia often clustered near vessels.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"89bcaf42-b4ab-5760-8c2e-44eace10cee0","slug":"iron","display_name":"Iron","entity_type_key":"nutrient_element"},"role":"histochemically detected nutrient element","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"36b7c3eb-068b-500f-af1c-078829df1ecc","slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"Thiamine disruption accompanies altered local iron handling; iron intake, chelation and iron-repletion response were not tested.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Results: Ferritin, Iron, and Microglial Responses to TD; Figure 7","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"iron accumulated in microglia","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Adult male C57BL/6 mice and Fischer 344 Brown Norway F1 rats; thiamine-deficient diet plus pyrithiamine 0.5 mg/kg/day intraperitoneally; staged brain histochemistry.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Dietary thiamine removal plus daily pyrithiamine in mice or rats","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Histochemistry does not establish iron origin, oxidation state or that dietary iron caused injury.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Thiamine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Mus musculus; Rattus norvegicus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Severe depletion changed where iron was retained in the brain.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[calingasan-1998-bbb-iron-nos] Induction of nitric oxide synthase and microglial responses precede selective cell death induced by chronic impairment of oxidative metabolism (1998). https://pmc.ncbi.nlm.nih.gov/articles/PMC1852979/ DOI: 10.1016/S0002-9440(10)65602-7","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Microglia in vulnerable thalamic and geniculate regions; rat inferior colliculus","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":"ebb9975c-3f56-5a1b-b457-534b06ef2084","evidence_kind":"source_excerpt","locator":"Lines 1225-1238","start_line":1225,"end_line":1238,"excerpt":"### thiamine-def-microglial-iron-accumulation\nIron accumulated in microglia of vulnerable mouse regions from day 10; rat iron-laden microglia often clustered near vessels.\nCondition category: nutrient_deficiency\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Severe depletion changed where iron was retained in the brain.\norganism: Mus musculus; Rattus norvegicus\ntissue_or_cell_type: Microglia in vulnerable thalamic and geniculate regions; rat inferior colliculus\nexperimental_model: Adult male C57BL/6 mice and Fischer 344 Brown Norway F1 rats; thiamine-deficient diet plus pyrithiamine 0.5 mg/kg/day intraperitoneally; staged brain histochemistry.\nlimitations: Histochemistry does not establish iron origin, oxidation state or that dietary iron caused injury.\nevidence_location: Results: Ferritin, Iron, and Microglial Responses to TD; Figure 7\nevidence_span: iron accumulated in microglia\ncross_nutrient: Thiamine disruption accompanies altered local iron handling; iron intake, chelation and iron-repletion response were not tested.\nexposure: Dietary thiamine removal plus daily pyrithiamine in mice or rats\n[calingasan-1998-bbb-iron-nos] Induction of nitric oxide synthase and microglial responses precede selective cell death induced by chronic impairment of oxidative metabolism (1998). https://pmc.ncbi.nlm.nih.gov/articles/PMC1852979/ DOI: 10.1016/S0002-9440(10)65602-7","model_system":"Adult male C57BL/6 mice and Fischer 344 Brown Norway F1 rats; thiamine-deficient diet plus pyrithiamine 0.5 mg/kg/day intraperitoneally; staged brain histochemistry.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [calingasan-1998-bbb-iron-nos] Induction of nitric oxide synthase and microglial responses precede selective cell death induced by chronic impairment of oxidative metabolism (1998). https://pmc.ncbi.nlm.nih.gov/articles/PMC1852979/ DOI: 10.1016/S0002-9440(10)65602-7","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"158d2c03-ac8c-589f-8270-c468165ae346","stable_key":"import-46d15d9e-d3b5-544d-ba01-b785aa3e4f42","title":"Thiamine: mechanisms, deficiency and nutrient interactions (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":"f376512fb3310141315548015b387833e3af45146e73fb73cd02cee20e4ddb9c","revision_id":"53bc5eda-dec8-58cc-a56f-a9eb4ab036ef","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}