{"id":"ca3a3563-a2b8-5f4a-985d-b06966c3b98d","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:ve-transport-rat-npc1l1-retinol-negative","predicate":"does_not_increase_uptake","statement":"Rat NPC1L1 overexpression mediated alpha-tocopherol uptake but did not mediate retinol uptake in the tested Caco-2 system.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"191770fe-1b24-54e2-b1d4-e87ac8d3f791","mechanism_event_label":"This vitamin E uptake route did not carry retinol in the same assay.","subject":{"id":"bd53dc6c-4bbd-54ad-8372-bf3130db1be7","slug":"rat-npc1l1","display_name":"Rat Niemann-Pick C1-like 1 protein","entity_type_key":"protein"},"object":{"id":"9baebdd1-a045-58e4-83e8-fa1dc55dde98","slug":"intestinal-retinol-uptake","display_name":"Intestinal retinol uptake","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"191770fe-1b24-54e2-b1d4-e87ac8d3f791","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:ve-transport-rat-npc1l1-retinol-negative-event","event_type":"biochemical_relationship","label":"This vitamin E uptake route did not carry retinol in the same assay.","description":"Rat NPC1L1 overexpression mediated alpha-tocopherol uptake but did not mediate retinol uptake in the tested Caco-2 system.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"bd53dc6c-4bbd-54ad-8372-bf3130db1be7","slug":"rat-npc1l1","display_name":"Rat Niemann-Pick C1-like 1 protein","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"9baebdd1-a045-58e4-83e8-fa1dc55dde98","slug":"intestinal-retinol-uptake","display_name":"Intestinal retinol uptake","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"148c57d8-c658-5769-89e8-1194cef2a782","slug":"retinol","display_name":"All-trans-retinol","entity_type_key":"small_molecule"},"role":"tested_vitamin_a_substrate","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"40a6525a-76b8-576e-b73d-1e11aecf5f8d","slug":"alpha-tocopherol","display_name":"Alpha-tocopherol","entity_type_key":"small_molecule"},"role":"positive_vitamin_e_substrate","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"true","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Rat NPC1L1-overexpressing human Caco-2 cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Retinol compared with alpha-tocopherol uptake; dose/time not reported in abstract.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Substrate-specific negative result; does not prove vitamins A and E cannot interact through other routes.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin E research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-e","display_name":"Vitamin E","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Rattus norvegicus protein; Homo sapiens cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"This vitamin E uptake route did not carry retinol in the same assay.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[narushima2008] Niemann-pick C1-like 1 mediates alpha-tocopherol transport. (2008). https://pubmed.ncbi.nlm.nih.gov/18403720/ DOI: 10.1124/mol.107.043034","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Intestinal epithelial cell model","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"649b7d30-d8e9-5099-bc5b-891f9c6f84cf","evidence_kind":"source_excerpt","locator":"Lines 233-244","start_line":233,"end_line":244,"excerpt":"### ve-transport-rat-npc1l1-retinol-negative\nRat NPC1L1 overexpression mediated alpha-tocopherol uptake but did not mediate retinol uptake in the tested Caco-2 system.\nCondition category: normal\nnutrient_topic: Vitamin E research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: This vitamin E uptake route did not carry retinol in the same assay.\norganism: Rattus norvegicus protein; Homo sapiens cells\ntissue_or_cell_type: Intestinal epithelial cell model\nexperimental_model: Rat NPC1L1-overexpressing human Caco-2 cells\nlimitations: Substrate-specific negative result; does not prove vitamins A and E cannot interact through other routes.\nexposure: Retinol compared with alpha-tocopherol uptake; dose/time not reported in abstract.\ncross_nutrient: true\n[narushima2008] Niemann-pick C1-like 1 mediates alpha-tocopherol transport. 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