{"id":"af69e203-da05-5eb2-9855-a145531141e5","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:ve-transport-gamma-multistep-cehc","predicate":"is_metabolized_to","statement":"HepG2 cultures exposed to gamma-tocopherol produced side-chain oxidation/shortening intermediates culminating in gamma-CEHC, identified by GC-MS.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"e94dbf4e-3fb7-5617-acb0-34581b778aa6","mechanism_event_label":"Several metabolic steps convert gamma-tocopherol into a shorter-chain product.","subject":{"id":"2de3a4d0-56b1-57f9-9e9d-934ba52a1753","slug":"gamma-tocopherol","display_name":"Gamma-tocopherol","entity_type_key":"small_molecule"},"object":{"id":"9a29222e-814f-572f-892d-1016a534506f","slug":"gamma-cehc","display_name":"Gamma-carboxyethyl hydroxychromanol","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"e94dbf4e-3fb7-5617-acb0-34581b778aa6","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:ve-transport-gamma-multistep-cehc-event","event_type":"biochemical_relationship","label":"Several metabolic steps convert gamma-tocopherol into a shorter-chain product.","description":"HepG2 cultures exposed to gamma-tocopherol produced side-chain oxidation/shortening intermediates culminating in gamma-CEHC, identified by GC-MS.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"2de3a4d0-56b1-57f9-9e9d-934ba52a1753","slug":"gamma-tocopherol","display_name":"Gamma-tocopherol","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"9a29222e-814f-572f-892d-1016a534506f","slug":"gamma-cehc","display_name":"Gamma-carboxyethyl hydroxychromanol","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"7fac36ce-6afb-59ca-9694-865c0b257f01","slug":"13-prime-hydroxy-gamma-tocopherol","display_name":"13′-Hydroxy-gamma-tocopherol","entity_type_key":"small_molecule"},"role":"early_pathway_intermediate","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"HepG2 metabolite profiling","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"50 µM gamma-tocopherol; primary Figure 1.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Pathway-level conversion; not a one-step CYP4F2 reaction or a human excretion-rate estimate.","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":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Several metabolic steps convert gamma-tocopherol into a shorter-chain product.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[sontag2002] Cytochrome P450 omega-hydroxylase pathway of tocopherol catabolism. Novel mechanism of regulation of vitamin E status. (2002). https://pubmed.ncbi.nlm.nih.gov/11997390/ DOI: 10.1074/jbc.m201466200","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Hepatoma cells","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"945c8148-d320-54b6-bb45-87729f4afa28","evidence_kind":"source_excerpt","locator":"Lines 428-439","start_line":428,"end_line":439,"excerpt":"### ve-transport-gamma-multistep-cehc\nHepG2 cultures exposed to gamma-tocopherol produced side-chain oxidation/shortening intermediates culminating in gamma-CEHC, identified by GC-MS.\nCondition category: normal\nnutrient_topic: Vitamin E research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Several metabolic steps convert gamma-tocopherol into a shorter-chain product.\norganism: Homo sapiens\ntissue_or_cell_type: Hepatoma cells\nexperimental_model: HepG2 metabolite profiling\nlimitations: Pathway-level conversion; not a one-step CYP4F2 reaction or a human excretion-rate estimate.\nexposure: 50 µM gamma-tocopherol; primary Figure 1.\ncross_nutrient: false\n[sontag2002] Cytochrome P450 omega-hydroxylase pathway of tocopherol catabolism. 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