{"id":"cafbd10a-ecfe-5322-8067-e9fa2c815634","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:e-sig-gamma-nitro-product","predicate":"is-nitrated-to","statement":"SIN-1 exposure converted gamma-tocopherol to 5-nitro-gamma-tocopherol in soybean phosphatidylcholine liposomes and isolated human LDL. Product yields were approximately 50% and 75%, respectively; alpha-tocopherol did not prevent gamma nitration.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"b7c8f166-c89e-5475-b6c0-ca6c5bfe6310","mechanism_event_label":"Gamma-tocopherol captured nitrating chemistry as a measurable nitrogen-containing product in artificial membranes and isolated blood lipoproteins.","subject":{"id":"2de3a4d0-56b1-57f9-9e9d-934ba52a1753","slug":"gamma-tocopherol","display_name":"Gamma-tocopherol","entity_type_key":"small_molecule"},"object":{"id":"a1e6571d-9c68-522e-9160-c71e77b931ab","slug":"5-nitro-gamma-tocopherol","display_name":"5-Nitro-gamma-tocopherol","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"b7c8f166-c89e-5475-b6c0-ca6c5bfe6310","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:e-sig-gamma-nitro-product-event","event_type":"biochemical_relationship","label":"Gamma-tocopherol captured nitrating chemistry as a measurable nitrogen-containing product in artificial membranes and isolated blood lipoproteins.","description":"SIN-1 exposure converted gamma-tocopherol to 5-nitro-gamma-tocopherol in soybean phosphatidylcholine liposomes and isolated human LDL. Product yields were approximately 50% and 75%, respectively; alpha-tocopherol did not prevent gamma nitration.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"3c107726-27bc-5c22-b2b0-4ee7f9837f7e","slug":"sin-1","display_name":"SIN-1 (3-morpholinosydnonimine)","entity_type_key":"small_molecule"},"role":"experimental nitrating-species generator","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"40a6525a-76b8-576e-b73d-1e11aecf5f8d","slug":"alpha-tocopherol","display_name":"Alpha-tocopherol","entity_type_key":"small_molecule"},"role":"tested coexisting tocopherol","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"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":2,"notes":""},{"entity":{"id":"a1e6571d-9c68-522e-9160-c71e77b931ab","slug":"5-nitro-gamma-tocopherol","display_name":"5-Nitro-gamma-tocopherol","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"HPLC analysis of tocopherols and nitration products","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Liposomes: 20 mM phosphatidylcholine, 20 µM tocopherol and 1 mM SIN-1 at 37°C. LDL: 0.2 mM SIN-1; Figure 3 initial gamma-tocopherol 0.98 µM.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"This identifies a stable nitration product, not every reactive intermediate or clinical anti-inflammatory efficacy. Liposome-versus-LDL antioxidant rankings differed.","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":"Cell-free and Homo sapiens-derived LDL","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Gamma-tocopherol captured nitrating chemistry as a measurable nitrogen-containing product in artificial membranes and isolated blood lipoproteins.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[christen1997] gamma-tocopherol traps mutagenic electrophiles such as NO(X) and complements alpha-tocopherol: physiological implications. (1997). https://pubmed.ncbi.nlm.nih.gov/9096373/ DOI: 10.1073/pnas.94.7.3217","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Soybean phosphatidylcholine liposomes; isolated plasma LDL","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"0c071ea8-b4db-54e7-9ce4-82b86031a4a1","evidence_kind":"source_excerpt","locator":"Lines 816-827","start_line":816,"end_line":827,"excerpt":"### e-sig-gamma-nitro-product\nSIN-1 exposure converted gamma-tocopherol to 5-nitro-gamma-tocopherol in soybean phosphatidylcholine liposomes and isolated human LDL. Product yields were approximately 50% and 75%, respectively; alpha-tocopherol did not prevent gamma nitration.\nCondition category: normal\nnutrient_topic: Vitamin E research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Gamma-tocopherol captured nitrating chemistry as a measurable nitrogen-containing product in artificial membranes and isolated blood lipoproteins.\norganism: Cell-free and Homo sapiens-derived LDL\ntissue_or_cell_type: Soybean phosphatidylcholine liposomes; isolated plasma LDL\nexperimental_model: HPLC analysis of tocopherols and nitration products\nlimitations: This identifies a stable nitration product, not every reactive intermediate or clinical anti-inflammatory efficacy. Liposome-versus-LDL antioxidant rankings differed.\nexposure: Liposomes: 20 mM phosphatidylcholine, 20 µM tocopherol and 1 mM SIN-1 at 37°C. LDL: 0.2 mM SIN-1; Figure 3 initial gamma-tocopherol 0.98 µM.\ncross_nutrient: false\n[christen1997] gamma-tocopherol traps mutagenic electrophiles such as NO(X) and complements alpha-tocopherol: physiological implications. (1997). https://pubmed.ncbi.nlm.nih.gov/9096373/ DOI: 10.1073/pnas.94.7.3217","model_system":"HPLC analysis of tocopherols and nitration products","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [christen1997] gamma-tocopherol traps mutagenic electrophiles such as NO(X) and complements alpha-tocopherol: physiological implications. (1997). https://pubmed.ncbi.nlm.nih.gov/9096373/ DOI: 10.1073/pnas.94.7.3217","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"3ac41dba-4727-5116-a556-ac3bbb0dc41c","stable_key":"import-e0ea2d6a-7429-5e9f-b774-41e5e3288da3","title":"Vitamin E: transport, membrane protection and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"a90b6565e092c6a2da07f74cf758792c2cf63b40746260c8ff12bd64322c36f4","revision_id":"956793d1-23e4-5397-9291-25c1732a8e02","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}