Melatonin Regulates Growth-Arrest and DNA-Damage Genes GADD153, GADD45g and GADD34 in Experimental Varicocele

This study aimed to reveal the relationship between experimental varicocele and melatonin levels. Forty adult Wistar albino rats were used in this study. Control (C), Melatonin (M), Varicocele (V), Varicocele+Melatonin (V + M) were planned. Varicocele was created on the first day of the experiment by opening the abdominal area, narrowing the left renal vein with a 0.85 mm metal wire and using a 4-0 silk suture, after removing the metal wire, the animal was closed (with a 3-0 silk suture) and kept for 60 days. Melatonin was administered at 10 mg/kg ip (intraperitoneal) on the 61st day, every 24 h for 7 days. Histological analysis and GADD34, GADD45g, GADD153 immunohistochemical staining were performed. Additionally, StAR and GDNF gene expressions were examined. ABP, FSH, LH, Testosterone, Melatonin hormones, TAS and TOS levels were evaluated from blood serum taken from experimental animals. According to our results, group V showed a decrease in testicular weights, seminiferous tubule diameter, and JTBS score, while GADD34, GADD45g and GADD153 proteins increased. In group V, testosterone and TAS levels decreased and TOS levels increased. In group V, testosterone, FSH, ABP, melatonin levels decreased and LH level increased. StAR and GDNF gene expression also decreased in group V. In the V + M group where melatonin was applied, an improvement was observed in biochemical parameters as well as histological, immunohistochemical and gene expression analyses. During varicocele, endogenous melatonin level decreases and activates various mechanisms and hormones in the tissue, including GADDs, causing loss of structure and function, while melatonin acts as a good therapeutic on varicocele.