Apoptosis-related gene expression of mice testicular germ cells following long-term leptin administration

Abstract

Leptin is a hormone which originates from fatty cells and regulates apoptosis in several cells and tissues, but there are few studies on testicular germ cells. In this study, the effects of leptin on the expression of the apoptosis regulator genes were evaluated in mice testicular germ cells. Thirty healthy mature male mice were assigned to the control and treatment groups in a random manner. Mice in the treatment group received an intraperitoneal injection of leptin hormone (0.1 μg/100 μL of physiological saline) daily for 30 sequential days and control animals received normal saline. From all animals, 15, 30, and 60 days after injection, 5 mice were randomly selected and slaughtered by the humane method. Left testicle was excreted in slaughtered mice and placed in formalin 10% to be used for immunohistochemical evaluations. The mean percentage of immunoreactive spermatogonia against BCL-2 decreased in the leptin-treated group at 30 and 60th days after treatment (P < 0.05). Although spermatogonia cells containing BAX did not increase significantly, spermatocytes containing BAX increased significantly in the treated group on days 30 and 60. Thus, the mean percentage of spermatocytes excluding BCL-2 in the leptin-administered group was significantly decreased on days 30 and 60 (P < 0.05). Based on our findings, leptin could increase the BAX/BCL-2 ratio and stimulate apoptosis in mice testicular spermatocytes.