{"id":"7394cfab-5c90-5ea0-a5b3-b77157efe6c6","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:b2-redox-gsh-needs-selenium-peroxidase","predicate":"fails-to-prevent-under-condition","statement":"Added glutathione failed to protect hemoglobin during oxidant challenge of selenium-deficient rat hemolyzates with very low glutathione-peroxidase activity.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"c523e49d-d0b5-585f-b2d3-94686c853e78","mechanism_event_label":"Supplying glutathione did not replace the missing selenium-dependent enzyme activity.","subject":{"id":"b44c9e27-4bbb-52d3-a022-14cddded5073","slug":"glutathione","display_name":"GSH","entity_type_key":"small_molecule"},"object":{"id":"0f8ad1fb-7193-578b-9db6-319980454eca","slug":"hemoglobin-oxidative-damage","display_name":"Hemoglobin oxidative damage","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"c523e49d-d0b5-585f-b2d3-94686c853e78","stable_key":"548ab9d6-3a9b-5bed-879c-17d03813b636:b2-redox-gsh-needs-selenium-peroxidase-event","event_type":"biochemical_relationship","label":"Supplying glutathione did not replace the missing selenium-dependent enzyme activity.","description":"Added glutathione failed to protect hemoglobin during oxidant challenge of selenium-deficient rat hemolyzates with very low glutathione-peroxidase activity.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"b44c9e27-4bbb-52d3-a022-14cddded5073","slug":"glutathione","display_name":"GSH","entity_type_key":"small_molecule"},"role":"added reductant","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"dc89d7e2-8f89-577b-838f-42bf5d8ec7c8","slug":"selenium","display_name":"Selenium","entity_type_key":"nutrient_element"},"role":"deficient nutrient","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"da9d64bc-69d4-5d97-90a4-8f0ed03e0ac8","slug":"hydrogen-peroxide","display_name":"Hydrogen peroxide","entity_type_key":"small_molecule"},"role":"one experimental oxidant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"0f8ad1fb-7193-578b-9db6-319980454eca","slug":"hemoglobin-oxidative-damage","display_name":"Hemoglobin oxidative damage","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"Explains why B2-dependent GSH recycling and selenium-dependent GSH use are distinct requirements.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Erythrocyte hemolyzates from selenium-deficient rats; glutathione addition during peroxide/ascorbate challenge and 75Se enzyme purification.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Selenium-deficient diet, then ex-vivo oxidant and glutathione exposure","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Separate from FAD-dependent GSR recycling; neither riboflavin nor combined nutrient repletion was tested.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Riboflavin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"riboflavin","display_name":"Riboflavin (vitamin B2)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Rattus norvegicus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Supplying glutathione did not replace the missing selenium-dependent enzyme activity.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[rotruck1973] Selenium: biochemical role as a component of glutathione peroxidase. (1973). https://pubmed.ncbi.nlm.nih.gov/4686466/ DOI: 10.1126/science.179.4073.588","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Erythrocyte hemolyzates","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"d93be693-27bb-5a70-8ab9-1f5c2036be8b","evidence_kind":"source_excerpt","locator":"Lines 1472-1484","start_line":1472,"end_line":1484,"excerpt":"### b2-redox-gsh-needs-selenium-peroxidase\nAdded glutathione failed to protect hemoglobin during oxidant challenge of selenium-deficient rat hemolyzates with very low glutathione-peroxidase activity.\nCondition category: nutrient_deficiency\nnutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Supplying glutathione did not replace the missing selenium-dependent enzyme activity.\norganism: Rattus norvegicus\ntissue_or_cell_type: Erythrocyte hemolyzates\nexperimental_model: Erythrocyte hemolyzates from selenium-deficient rats; glutathione addition during peroxide/ascorbate challenge and 75Se enzyme purification.\nlimitations: Separate from FAD-dependent GSR recycling; neither riboflavin nor combined nutrient repletion was tested.\nexposure: Selenium-deficient diet, then ex-vivo oxidant and glutathione exposure\ncross_nutrient: Explains why B2-dependent GSH recycling and selenium-dependent GSH use are distinct requirements.\nevidence_location: Abstract\n[rotruck1973] Selenium: biochemical role as a component of glutathione peroxidase. 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