{"id":"4c13584f-7dd5-5b28-b120-ce0e0d14d8d1","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:ver-gpx4-cholesterol-hydroperoxide","predicate":"reduces","statement":"GSH/PHGPX reduced membrane cholesterol hydroperoxides, predominantly the photo-generated 5-alpha product, to diol-like products; cholesterol hydroperoxide decay was about one-sixth the phospholipid hydroperoxide decay rate in the ghost-membrane assay.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"db6241bf-6623-50a6-98f7-a54fac4da1a1","mechanism_event_label":"The enzyme also removed peroxide groups from oxidized cholesterol, more slowly than from phospholipids in this preparation.","subject":{"id":"e9bb13ee-f238-51e6-9101-78ddfd11465c","slug":"gpx4","display_name":"GPX4","entity_type_key":"protein"},"object":{"id":"b84d9ed8-67bb-5943-a611-38fc1eb32c22","slug":"cholesterol-hydroperoxides","display_name":"Cholesterol hydroperoxides","entity_type_key":"lipid"},"evidence_count":1,"mechanism_event":{"id":"db6241bf-6623-50a6-98f7-a54fac4da1a1","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:ver-gpx4-cholesterol-hydroperoxide-event","event_type":"biochemical_relationship","label":"The enzyme also removed peroxide groups from oxidized cholesterol, more slowly than from phospholipids in this preparation.","description":"GSH/PHGPX reduced membrane cholesterol hydroperoxides, predominantly the photo-generated 5-alpha product, to diol-like products; cholesterol hydroperoxide decay was about one-sixth the phospholipid hydroperoxide decay rate in the ghost-membrane assay.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"b44c9e27-4bbb-52d3-a022-14cddded5073","slug":"glutathione","display_name":"GSH","entity_type_key":"small_molecule"},"role":"reducing cosubstrate","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"77e0cc8a-2d04-5c71-a3b7-425ce85d630e","slug":"cholesterol-diols","display_name":"Cholesterol diols","entity_type_key":"lipid"},"role":"products","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"e9bb13ee-f238-51e6-9101-78ddfd11465c","slug":"gpx4","display_name":"GPX4","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"b84d9ed8-67bb-5943-a611-38fc1eb32c22","slug":"cholesterol-hydroperoxides","display_name":"Cholesterol hydroperoxides","entity_type_key":"lipid"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"true","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Radiolabeled sterol analysis in erythrocyte ghosts","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Photooxidation followed by GSH/PHGPX.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Product co-migration and assay-specific relative kinetics; no universal cellular rate.","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-derived cell-free membranes","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The enzyme also removed peroxide groups from oxidized cholesterol, more slowly than from phospholipids in this preparation.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[ver-thomas1990] Protective action of phospholipid hydroperoxide glutathione peroxidase against membrane-damaging lipid peroxidation. In situ reduction of phospholipid and cholesterol hydroperoxides. (1990). https://pubmed.ncbi.nlm.nih.gov/2294113/ DOI: 10.1016/s0021-9258(19)40252-4","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Erythrocyte ghosts","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"adfbd744-82a2-5726-b2ce-b5d55ba8178f","evidence_kind":"source_excerpt","locator":"Lines 564-576","start_line":564,"end_line":576,"excerpt":"### ver-gpx4-cholesterol-hydroperoxide\nGSH/PHGPX reduced membrane cholesterol hydroperoxides, predominantly the photo-generated 5-alpha product, to diol-like products; cholesterol hydroperoxide decay was about one-sixth the phospholipid hydroperoxide decay rate in the ghost-membrane assay.\nCondition category: normal\nnutrient_topic: Vitamin E research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The enzyme also removed peroxide groups from oxidized cholesterol, more slowly than from phospholipids in this preparation.\norganism: Human-derived cell-free membranes\ntissue_or_cell_type: Erythrocyte ghosts\nexperimental_model: Radiolabeled sterol analysis in erythrocyte ghosts\nlimitations: Product co-migration and assay-specific relative kinetics; no universal cellular rate.\nexposure: Photooxidation followed by GSH/PHGPX.\ncross_nutrient: true\nevidence_location: Primary abstract\n[ver-thomas1990] Protective action of phospholipid hydroperoxide glutathione peroxidase against membrane-damaging lipid peroxidation. 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