{"id":"8ce44798-9524-5772-aa70-301e36c65233","stable_key":"c953cca8-774f-596d-b27a-f13c2c0b5fce:dhc-liver-not-brain","predicate":"is_metabolised_by","statement":"Dihydrocapsaicin was metabolized when incubated in vitro with liver tissue but not with brain tissue, a certain degree of biotransformation already took place in the intestinal lumen, there appears to be a saturable absorption and degradation process in the gastrointestinal tract and very effective metabolism in the liver, and the metabolic products did not show capsaicin-like biological activity.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"e43de584-5c35-5625-b093-3be1844921c5","mechanism_event_label":"The liver breaks it down and the brain does not, and what the liver makes is inert.","subject":{"id":"6259a8e0-9611-5f60-9e1b-53bbd8eb1afd","slug":"dihydrocapsaicin","display_name":"Dihydrocapsaicin","entity_type_key":"small_molecule"},"object":{"id":"a90f9522-4936-5f31-b64e-f11a9c3d9e06","slug":"first-pass-metabolism","display_name":"First-pass metabolism during and after absorption","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"e43de584-5c35-5625-b093-3be1844921c5","stable_key":"c953cca8-774f-596d-b27a-f13c2c0b5fce:dhc-liver-not-brain-event","event_type":"biochemical_relationship","label":"The liver breaks it down and the brain does not, and what the liver makes is inert.","description":"Dihydrocapsaicin was metabolized when incubated in vitro with liver tissue but not with brain tissue, a certain degree of biotransformation already took place in the intestinal lumen, there appears to be a saturable absorption and degradation process in the gastrointestinal tract and very effective metabolism in the liver, and the metabolic products did not show capsaicin-like biological activity.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"f11ad889-e387-57b7-a61b-e6c620aa2ffb","slug":"antinociceptive-activity","display_name":"Antinociceptive activity","entity_type_key":"cellular_process"},"role":"lost_property","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"6259a8e0-9611-5f60-9e1b-53bbd8eb1afd","slug":"dihydrocapsaicin","display_name":"Dihydrocapsaicin","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"a90f9522-4936-5f31-b64e-f11a9c3d9e06","slug":"first-pass-metabolism","display_name":"First-pass metabolism during and after absorption","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/dihydrocapsaicin-research/2280802.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"92a4527b69cd4c342da3d0aed850597ef4491122baf20b6a681e43ab0a8e2dd1\", \"start_char\": 0, \"end_char\": 1280, \"text_sha256\": \"92a4527b69cd4c342da3d0aed850597ef4491122baf20b6a681e43ab0a8e2dd1\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Intragastric, intravenous and subcutaneous administration of tritiated dihydrocapsaicin in anaesthetised rats with tissue extraction","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Tritiated dihydrocapsaicin and unlabelled capsaicin given intragastrically, intravenously or subcutaneously","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"The comparison across routes is the point, and it is the reason every hypothermia study in this collection injects the drug rather than feeding it. Anaesthetised rats, and identification is chromatographic.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Dihydrocapsaicin research collection; topical membership is not evidence of a direct clinical effect, and dihydrocapsaicin is recorded separately from capsaicin.","comparator":null,"unit":null,"notes":"","entity":{"slug":"dihydrocapsaicin","display_name":"Dihydrocapsaicin","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Rat","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The liver breaks it down and the brain does not, and what the liver makes is inert.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[dhc-p2280802] Absorption and metabolism of capsaicinoids following intragastric administration in rats. 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Anaesthetised rats, and identification is chromatographic.\nexposure: Tritiated dihydrocapsaicin and unlabelled capsaicin given intragastrically, intravenously or subcutaneously\nevidence_span: {\"source_cache\": \"artifacts/dihydrocapsaicin-research/2280802.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"92a4527b69cd4c342da3d0aed850597ef4491122baf20b6a681e43ab0a8e2dd1\", \"start_char\": 0, \"end_char\": 1280, \"text_sha256\": \"92a4527b69cd4c342da3d0aed850597ef4491122baf20b6a681e43ab0a8e2dd1\"}\n[dhc-p2280802] Absorption and metabolism of capsaicinoids following intragastric administration in rats. 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