Effects of all trans retinoic acid on testicular damage induced by acrylamide during prepubertal period

Acrylamide is a water soluble and neurotoxic, genotoxic and probably carcinogenic chemical appeared through heat treatment especially on carbohydrate rich foods. All-trans retinoic acid (ATRA) is a vitamin A metabolite essential for testicular development and male fertility. In this study, we aimed for identifying the protective effects of all-trans retinoic acid (ATRA) on testicular damage caused by acrylamide toxicity during prepubertal period and galectin-3 immunereactivity believed to be generated in the inflamation and fibrosis processes. 24 Wistar Albino species 4 week old male rats were used in this study. The rats were divided into 4 groups. The rats in Group I were identified as the control group. The rats in Group II were injected 40 mg/kg/day acrylamide for 4 weeks; the rats in Group III were administered 40 mg/kg/day acrylamide and 5 mg/kg/day all-trans retinoic acid, for 4 weeks and the rats in Group IV were administered 5 mg/kg/day all-trans retionic acid for 4 weeks. At the end of the experiment, the rats were decapitated under anesthesia. Blood samples for measurement of serum/testosterone levels and testicular tissues for histopathologic analyses were taken from the all of rats. Paraffin blocks were prepared with the routine tissue preparation method. 5µm thick tissue sections were obtained from the paraffin blocks and stained with histochemical and immunohistochemical methods and than examined. In histopathologic analyses, seminiferous tubule epithelium and interstitial region of the control group testicular tissues had a normal appearance. Acriylamide injection caused to, vacuolization, atrophy, multinuclear giant cell formations in the seminiferous tubule epithelium and rashes of cells of immature spermatogenic series were distinguished in the tubule lumen. Futhermore, edematous findings were observed sporadically in the interstitial area. Vacuolization and atrophy were obseved in same of seminiferous tubules. Although ATRA administration provided prominent protection in the testicular tissue against acrylamide intoxication. The tissue sections of the group only administered ATRA were similar to those of the control group. Examination of galectin-3 immunoreactivity, spermatogenic and Leydig cells were significantly marked in groups II and III while galectin-3 expression was not noticeable in groups I and IV. It was determined by the measurements of the serum testosterone level that acrylamide administration significantly reduced the serum testosterone level. It was observed that acrylamide, which had been exposed to in the prepubertal period, caused severe damages to the testicle on both structural and physiologic terms. This damage is at a high level which might cause infertility risk in children in the development period with habitual "fast food" consumption. Moreover there was a positive correlation between testicular damage and galectin-3 immunoreactivity. ATRA was found to provide a significant protection against the damage caused by acrylamide. Keywords: Acrylamide, All Trans Retinoic Acid, Galectin-3, Testis, immunohistochemistry.