Vitamin B12 protects against superoxide-induced cell injury in human aortic endothelial cells.

Title

Vitamin B12 protects against superoxide-induced cell injury in human aortic endothelial cells.

Creator

Moreira Edward S; Brasch Nicola E; Yun June

Publisher

Free radical biology & medicine

Date

2011
2011-08

Description

Superoxide (O(2)(*-)) is implicated in inflammatory states including arteriosclerosis and ischemia-reperfusion injury. Cobalamin (Cbl) supplementation is beneficial for treating many inflammatory diseases and also provides protection in oxidative-stress-associated pathologies. Reduced Cbl reacts with O(2)(*-) at rates approaching that of superoxide dismutase (SOD), suggesting a plausible mechanism for its anti-inflammatory properties. Elevated homocysteine (Hcy) is an independent risk factor for cardiovascular disease and endothelial dysfunction. Hcy increases O(2)(*-) levels in human aortic endothelial cells (HAEC). Here, we explore the protective effects of Cbl in HAEC exposed to various O(2)(*-) sources, including increased Hcy levels. Hcy increased O(2)(*-) levels (1.6-fold) in HAEC, concomitant with a 20% reduction in cell viability and a 1.5-fold increase in apoptotic death. Pretreatment of HAEC with physiologically relevant concentrations of cyanocobalamin (CNCbl) (10-50nM) prevented Hcy-induced increases in O(2)(*-) and cell death. CNCbl inhibited both Hcy and rotenone-induced mitochondrial O(2)(*-) production. Similarly, HAEC challenged with paraquat showed a 1.5-fold increase in O(2)(*-) levels and a 30% decrease in cell viability, both of which were prevented with CNCbl pretreatment. CNCbl also attenuated elevated O(2)(*-) levels after exposure of cells to a Cu/Zn-SOD inhibitor. Our data suggest that Cbl acts as an efficient intracellular O(2)(*-) scavenger.

Subject

Aorta/pathology; Apoptosis/drug effects; Atherosclerosis/*drug therapy/metabolism/pathology/physiopathology; Cell Line; Cell Survival/drug effects; Cytoprotection; Endothelium; Free Radical Scavengers/*pharmacology; Humans; Mitochondria/drug effects/metabolism/pathology; Oxidative Stress/drug effects; Reperfusion Injury/*drug therapy/metabolism/pathology/physiopathology; Superoxides/metabolism; Vascular/*drug effects/metabolism/pathology; Vitamin B 12/*pharmacology; Vitamin B Complex/*pharmacology

Rights

Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).

Pages

876–883

Issue

4

Volume

51

Citation

Moreira Edward S; Brasch Nicola E; Yun June, “Vitamin B12 protects against superoxide-induced cell injury in human aortic endothelial cells.,” NEOMED Bibliography Database, accessed September 20, 2021, https://neomed.omeka.net/items/show/3565.

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