Modulatory Effects of Lipoic Acid and Selenium Against Cadmium-Induced Biochemical Alterations in Testicular Steroidogenesis

Exposure to toxic metals including cadmium has become an increasingly recognized source of illness worldwide. Cadmium (Cd2+) is one of the environmental pollutants affecting various tissues and organs including testis. The protective effect of lipoic acid and selenium on Cd2+-induced testicular damage was investigated. Accordingly, male Wistar rats were allocated into four groups (n = 8; each). Gp I: (control), whereas the other 3 groups received CdCl2 (2 mg/kg, i.p. for 28 days) alone or in combination with either (i) lipoic acid (35 mg/kg, p.o) or (ii) selenium (0.35 mg/kg, p.o) throughout the experiment. Serum testosterone, luteinizing hormone and folliclestimulating hormone levels significantly decreased in the Cd2+-exposed rats. The activities of testicular key androgenic enzymes, 30-hydroxysteroid dehydrogenase and 17 beta-HSD significantly decreased in Cd2+-exposed rats compared to the control counterparts. In addition, the activities of testicular marker enzymes were significantly altered in cadmium-treated animals. Significant reductions in body and testicular weight as well as antioxidant status were also observed in Cd2+-exposed rats. Moreover, some testicular metal levels were altered. Lipoic acid and selenium significantly increased serum testosterone level and restored testicular activity of 3 beta-HSD and 17 beta-HSD and were effective in modulation of most of the measured biochemical parameters. The biochemical parameters were further confirmed with histopathological findings. In conclusion, the present study demonstrated the beneficial influences of lipoic acid and selenium in reducing harmful effects of Cd2+ in rats' testes. (C) 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:15-25, 2011; View this article online at wileyonlinelibrary.com. DOI 10:1002/jbt.20354