Effects of Rosiglitazone and Vitamin E on Testicular Tissue and Sperm Parameters in Propylthiouracil-Induced Hypothyroidism in Rats

Thyroid dysfunction has been reported to negatively affect the male reproductive system. A clear link exists between thyroid hormone (TH) and testicular development and function. Here, the effects of one of the peroxisome proliferator-activated receptor-gamma agonists, rosiglitazone (RSG), and vitamin E (Vit E) on testicular histology in propylthiouracil (PTU)-induced hypothyroidism were investigated. Thirty-five juvenile male Wistar rats were included in 5 groups: control group, hypothyroid group which received 0.05% PTU in drinking water, and rats in groups 3 and 4 besides PTU, treated with 4 mg/kg RSG and 20 mg/kg Vit E, respectively. Animals in group 5 received only 20 mg/kg Vit E. Germ cell apoptosis was determined by transferase-mediated dUTP nick-end labeling (TUNEL) assay as well as the swimout sperm analyzed for count, morphology, and sperm chromatin quality. The sperm morphology and chromatin quality were evaluated with Papanicolaou and Toluidine blue (TB) stainings. Exposure to PTU significantly increased TUNEL-positive germ cells of the testis, while RSG and Vit E administration decreased significantly apoptotic germ cells. Moreover, in hypothyroid rats, sperm count, normal morphology, and sperm chromatin quality significantly decreased. In contrast, RSG and Vit E improved sperm parameters compared to the hypothyroid group. Thus, RSG and Vit E appear to provide protective impacts against testicular damages induced by hypothyroidism.