Restricted food intake promotes accumulation of proliferation-, apoptosis-, and anti–apoptotic-related peptides in rat testicular cells

The aim of this study was to examine the effects of short-term dietary energy restriction (50% of standard ration for 20 days) on somatic and testicular growth as well as on proliferation and apoptosis of testicular cells in prepubertal Wistar rats. The influence of food restriction on animal growth (body mass and daily gain), in vivo testicular growth (testis mass), and indexes of testicular cell proliferation (expression of proliferating cell nuclear antigen and cyclin B1) and apoptosis (caspase 3, bax, and bcl-2) in testicular tissue isolated from these rats and cultured during 24 hours was evaluated using sodium dodecyl sulfate–polyacrylamide gel electrophoresis Western immunoblotting. It was observed that restricted feeding resulted in a significant reduction in animal body weight and daily gain, but not in testicular mass. Furthermore, food restriction induced a dramatic accumulation of proliferation-associated antigens (proliferating cell nuclear antigen and cyclin B1), apoptosis-associated peptides (caspase 3 and bax), and antiapoptotic peptide (bcl-2) in testicular tissue. The data suggest that low energy intake can activate proliferation and accumulation of both apoptotic and antiapoptotic substances in testicular tissue to promote testicular cell turnover and tissue remodeling.