{"id":"359cb77d-a3e5-5761-a621-5e4e90628f3a","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:ver-repair-extracellular-calcium","predicate":"is-required-for","statement":"Alpha-tocopherol-loaded HeLa cells still failed to restrict dye entry after laser injury when extracellular calcium was omitted, despite improved repair in calcium-containing buffer.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"1491a4b9-412b-5e61-bb33-04d7cb6d94f7","mechanism_event_label":"Vitamin E loading did not eliminate the need for extracellular calcium during membrane repair.","subject":{"id":"e359bc15-e675-5d83-b0fe-1d70814e130b","slug":"calcium-ion","display_name":"Calcium ion","entity_type_key":"ion"},"object":{"id":"19860ac9-fc80-51bb-9bee-33f193616b4c","slug":"plasma-membrane-repair","display_name":"Plasma membrane repair","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"1491a4b9-412b-5e61-bb33-04d7cb6d94f7","stable_key":"e0ea2d6a-7429-5e9f-b774-41e5e3288da3:ver-repair-extracellular-calcium-event","event_type":"biochemical_relationship","label":"Vitamin E loading did not eliminate the need for extracellular calcium during membrane repair.","description":"Alpha-tocopherol-loaded HeLa cells still failed to restrict dye entry after laser injury when extracellular calcium was omitted, despite improved repair in calcium-containing buffer.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"1e078aed-0416-5fe7-8b8b-36bc2ca8ab7a","slug":"all-rac-alpha-tocopherol","display_name":"All-rac-alpha-tocopherol","entity_type_key":"small_molecule"},"role":"preloaded antioxidant","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"e359bc15-e675-5d83-b0fe-1d70814e130b","slug":"calcium-ion","display_name":"Calcium ion","entity_type_key":"ion"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"19860ac9-fc80-51bb-9bee-33f193616b4c","slug":"plasma-membrane-repair","display_name":"Plasma membrane repair","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"true","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Figure 1c","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Laser wounding with extracellular calcium control","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"200 µM racemic alpha-tocopherol (96% pure) for 24 h; with versus without added extracellular calcium.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Acute assay calcium removal is not dietary calcium deficiency; does not identify the calcium sensor.","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":"Vitamin E loading did not eliminate the need for extracellular calcium during membrane repair.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[ver-howard2011] Promotion of plasma membrane repair by vitamin E. (2011). https://pubmed.ncbi.nlm.nih.gov/22186893/ DOI: 10.1038/ncomms1594","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"HeLa cells","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"e9e9b0b4-bb68-5f3f-845a-12bc569b45d1","evidence_kind":"source_excerpt","locator":"Lines 676-688","start_line":676,"end_line":688,"excerpt":"### ver-repair-extracellular-calcium\nAlpha-tocopherol-loaded HeLa cells still failed to restrict dye entry after laser injury when extracellular calcium was omitted, despite improved repair in calcium-containing buffer.\nCondition category: normal\nnutrient_topic: Vitamin E research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Vitamin E loading did not eliminate the need for extracellular calcium during membrane repair.\norganism: Homo sapiens\ntissue_or_cell_type: HeLa cells\nexperimental_model: Laser wounding with extracellular calcium control\nlimitations: Acute assay calcium removal is not dietary calcium deficiency; does not identify the calcium sensor.\nexposure: 200 µM racemic alpha-tocopherol (96% pure) for 24 h; with versus without added extracellular calcium.\ncross_nutrient: true\nevidence_location: Figure 1c\n[ver-howard2011] Promotion of plasma membrane repair by vitamin E. 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