Role of KU70, SIRT1, and SIRT6 Proteins in Diabetic Rat Testis Tissue

Abstract

Diabetic male infertility/subfertility is an important complication of diabetes. The molecular mechanisms responsible for this complication have not been thoroughly investigated. We aimed to elucidate the role of KU70, SIRT1, and SIRT6 proteins in diabetic testis. Sprague–Dawley male rats were maintained under stable laboratory conditions. The rats were divided into a control group (n=8) and a diabetes group (n=8 treated with a single dose of 50 mg/kg streptozotocin). At the end of the 1-month experimental period, animals were sacrificed under anesthesia. Both testicles were removed, processed lightly, and studied through electron transmission microscopy and western blotting. Blood samples were collected for biochemical analysis. Histopathological analysis revealed that, in the diabetes group, the diaphragmatic tubule diameters and serum testosterone levels were decreased. KU70 immunoreactivity was statistically significantly increased, whereas SIRT1 and SIRT6 expression was significantly decreased compared with that observed in the control group. This is the first study to examine the expression of KU70, SIRT1, and SIRT6 in diabetic testicular tissue for the first time. According to the results, KU70, SIRT1, and SIRT6 may play an important role in cell apoptosis in diabetic testicular tissue. Importance of these proteins should be investigated further in additional quantitative studies.

Keywords

• Bax/Bcl2-ratio
• TUNEL assay
• Rat
• Apoptosis
• Histology

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