Expression of Bax and Bcl-2 Apoptotic Regulatory Proteins in Melphalan-induced Spermatogenic Dysfunction

Abstract

The adverse effect of Melphalan (MEP), an anti-cancer compound in the male reproductive system, was investigated. In this study, 1, 3, or 5 mg/kg/bwt intraperitoneal doses of MEP were administered daily for 28 days. Half of the mice were sacrificed after 24 hours of the last treatment, and the other half were sacrificed 28 days after withdrawal of treatment. Glutathione peroxidase (GPX), glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD), reactive oxygen species (ROS) and lipid peroxidation (LPO) levels of testicular tissue were evaluated. The induction of apoptosis was assessed by investigating the level of CASP-3 and CASP-9 activities in spermatogenic cells. CASP- 9, Bax and BCL-2 expression were checked by real-time PCR and western blotting. Testis weight in MEP-treated mice was significantly decreased. There was a significant decrease in sperm parameters, GSH GPx, CAT, and SOD levels, with a concomitant increase in ROS and MDA levels confirming the generation of oxidative stress. MEP-treatment leads to the increased expression of CASP-9, BAX, with decreased BCL-2 protein levels in a dosedependent manner. No significant recovery after 28 days of withdrawal of the treatment was observed. The results indicate that MEP- treatment leads to testicular damage due to the formation of oxidative stress and induction of caspase-dependent apoptosis.