Effects of Vitamin E Supplementation in Male Rats with Crude Oil-Induced Reproductive Toxicity

Abstract

Crude oil intoxication is a major threat among people and animals living around the crude oil producing regions of the world, hence the search for ameliorating agents. Forty-four male Wistar rats assigned into three groups were used to investigate the effects of vitamin E supplementation on crude oil-induced reprotoxicity (reproductive toxicity) in male rats. Group A represented the unexposed control, whereas groups B and C were exposed orally to 0.15 and 0.3 ml of crude oil respectively every other day for 56 days. Both the low dose and high dose oral administration of crude oil caused a significant reduction in the serum testosterone level (STL) and cauda epididymal sperm reserve (CESR) of the exposed rats when compared to the control. Crude oil withdrawal and vitamin E supplementation significantly improved the cauda epididymal sperm reserve (CESR) in all the subgroups. The serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities of the control and low dose group were significantly lower than those of the high dose group. The high dose crude oil administration significantly decreased the mean serum total protein (STP) and sodium ions (Na⁺) concentration. The mean serum total cholesterol (STC) value of the low dose group was significantly higher than those of the control and high dose group. However, crude oil withdrawal and vitamin E supplementation did not significantly alter the mean serum total protein (STP) and mean serum total cholesterol (STC) values in all the subgroups. Vitamin E supplementation following low dose crude oil withdrawal enhanced the mean serum Chloride ions (Cl^-)concentration. The present findings revealed that Nigerian Qua Iboe Brent crude oil induced serious reprotoxic effects in male rats which vitamin E administration within 28 days did not completely reverse.