{"id":"3df33f61-9a86-5e56-a248-98c11b76d18b","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:ve-transport-npc1l1-cholesterol-competition","predicate":"reduces_uptake","statement":"Cholesterol inhibited human NPC1L1-mediated alpha-tocopherol uptake in mutual substrate-interaction experiments.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"4fa2c79e-5287-5687-b9bd-3e2ca9e17219","mechanism_event_label":"Cholesterol changed vitamin E uptake through their shared transporter.","subject":{"id":"d3a1b93d-0a2c-5d1b-b672-5e4ef4b09a10","slug":"cholesterol","display_name":"Cholesterol","entity_type_key":"lipid"},"object":{"id":"3436f320-f9dd-5606-9a37-507e5944ee6c","slug":"intestinal-alpha-tocopherol-uptake","display_name":"Intestinal alpha-tocopherol uptake","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"4fa2c79e-5287-5687-b9bd-3e2ca9e17219","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:ve-transport-npc1l1-cholesterol-competition-event","event_type":"biochemical_relationship","label":"Cholesterol changed vitamin E uptake through their shared transporter.","description":"Cholesterol inhibited human NPC1L1-mediated alpha-tocopherol uptake in mutual substrate-interaction experiments.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"d3a1b93d-0a2c-5d1b-b672-5e4ef4b09a10","slug":"cholesterol","display_name":"Cholesterol","entity_type_key":"lipid"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"3436f320-f9dd-5606-9a37-507e5944ee6c","slug":"intestinal-alpha-tocopherol-uptake","display_name":"Intestinal alpha-tocopherol uptake","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"9fbf0133-53c3-5ab1-8a95-4804d6115300","slug":"npc1l1","display_name":"Human Niemann-Pick C1-like protein 1 / NPC1L1","entity_type_key":"protein"},"role":"shared_transporter","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":"uptake_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":"Human NPC1L1 overexpression co-substrate assay","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Cholesterol and alpha-tocopherol co-incubation; concentrations unavailable in abstract.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"No dietary cholesterol threshold or universal supplement-spacing rule follows.","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":"Human protein in cultured cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Cholesterol changed vitamin E uptake through their shared transporter.","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":"Cellular uptake model","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"698e0741-04dc-5aea-8a6f-601971087ee3","evidence_kind":"source_excerpt","locator":"Lines 220-231","start_line":220,"end_line":231,"excerpt":"### ve-transport-npc1l1-cholesterol-competition\nCholesterol inhibited human NPC1L1-mediated alpha-tocopherol uptake in mutual substrate-interaction experiments.\nCondition category: normal\nnutrient_topic: Vitamin E research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Cholesterol changed vitamin E uptake through their shared transporter.\norganism: Human protein in cultured cells\ntissue_or_cell_type: Cellular uptake model\nexperimental_model: Human NPC1L1 overexpression co-substrate assay\nlimitations: No dietary cholesterol threshold or universal supplement-spacing rule follows.\nexposure: Cholesterol and alpha-tocopherol co-incubation; concentrations unavailable in abstract.\ncross_nutrient: true\n[narushima2008] Niemann-pick C1-like 1 mediates alpha-tocopherol transport. 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