Inhibitive effects of anti-oxidative vitamins on mannitol-induced apoptosis of vascular endothelial cells.

Objective: Study blood vessel injury and gene expression indicating vascular endothelial cell apoptosis induced by mannitol with and without administration of anti-oxidative vitamins.

Methods: Healthy rabbits were randomly divided into four groups. Mannitol was injected into the vein of the rabbit ear in each animal. Pre-treatment prior to mannitol injection was performed with normal saline (group B), vitamin C (group C) and vitamin E (group D). Blood vessel injury was assessed under electron and light microscopy. In a second experiment, cell culture specimen of human umbilical vein endothelial cells were treated with mannitol. Pre-treatment was done with normal saline (sample B), vitamin C (sample C) and vitamin E (sample D). Total RNA was extracted with the original single step procedure, followed by hybridisation and analysis of gene expression.

Results: In the animal experiment, serious blood vessel injury was seen in group A and group B. Group D showed light injury only, and normal tissue without pathological changes was seen in group C. Of all 330 apoptosis-related genes analysed in human cell culture specimen, no significant difference was seen after pre-treatment with normal saline, compared with the gene chip without pre-treatment. On the gene chip pre-treated with vitamin C, 45 apoptosis genes were down-regulated and 34 anti-apoptosis genes were up-regulated. Pre-treatment with vitamin E resulted in the down-regulation of 3 apoptosis genes.

Conclusion: Vitamin C can protect vascular endothelial cells from mannitol-induced injury.