The effects of carnosine on cyclophosphamide inducedtesticular injury

Objective: Cyclophosphamide is a drug used in the treatment of rheumatoid arthritis, SLE, multiple sclerosis and many cancers. After the metabolic activation in the liver, it forms toxic metabolites that form reactive oxygen radicals in the body. Recent studies shows that cyclophosphamide has many cytotoxic effects on testis; such as decrease in testicular weight, oligospermia, decrease in DNA synthesis in spermatogonia. Carnosine is a natural antioxidant dipeptide synthesized in the human muscle and nervous tissue. It can easily absorbable from the digestive system. A study involving the effects of carnosine in experimental model of testis injury induced by cyclophosphamide has not been found in the literature. The aim of this study is to investigate the damage caused by the cyclophosphamide on the testis of male rats and to show the effect of carnosine by light microscopy, immunohistochemistry and biochemistry. Method: In the study, 40 Wistar Albino strains 10-12 weeks (200-250gr) were divided into six groups . We used five subjects in the control group and seven subjects in the other experimental groups. Drugs used in the experiment were carnosine 250 mg / kg, cyclophosphamide 150 mg / kg intraperitoneal (i.p.). Control group; any drug and solvent-free group, cyclophosphamide (CP) group; the group which is given only a single dose of cyclophosphamide, carnosine group (K); only carnosine given group, (K + CP) group; first single dose carnosine and one hour later cyclophosphamide were given, (K = CP) group; carnosine and cyclophosphamide were given at the same time, group (CP + K) group; first single dose cyclophosphamide and one hour later carnosine were given. Forty-eight hours after the last dose of all groups, testicular tissue specimens were taken and fixed. After routine histological follow-up, testicular tissues were embedded in paraffin blocks. Sections with a thickness of five μm were taken from each block. Morphology of testis tissue with hematoxylin-eosin, measurement of seminiferous tubule diameter, Johnsen scoring; basal membrane thickness measurement with PAS staining; the connective tissue was examined with Masson's Trichrome staining. Immunohistochemically, immunohistochemical staining with anti-claudin5 and active caspase-3 antibodies was performed. Result: Normal testicular histologic structure was observed in control and carnosine group. Cyclophosphamide group showed significant germinal epithelial damage with the hematoxyline-eosin stain. The germinal epithelium of the seminiferous tubule detached from the basal membrane (basal membrane ondulation). Although there were erythrocytes in the interstitial space between some seminiferous tubules; it was observed that in many seminiferous tubules, spermatogenic series cells were undamaged, the germinal epithelium was regular and alignment disorder was decreased in the both carnosine and cyclophosphamide used three groups. There was an increase in collagen levels in the intertubular connective tissue in the cyclophosphamide group compared to the other groups with the Masson-trichrom stain. There was an increase in basal membrane thickness at the cyclophosphamide group when compared to the other groups with the PAS stain. Immunohistochemically, active caspase-3 and decreased anti-claudin5 immunoreactivity were observed in the cyclophosphamide group compared to the other groups. Conclusion: According to our findings, cyclophosphamide has protective and therapeutic effect of carnosine in testicular damage