Insulin treatment to type 1 male diabetic rats protects fertility by avoiding testicular apoptosis and cell cycle arrest.

BACKGROUND: Uncontrolled type 1 diabetes mellitus (T1D) impairs reproductive potential of males. Insulin treatment restores metabolic parameters but it is unclear how it protects male reproductive health. Herein, we hypothesized that insulin treatment to T1D rats protects testicular physiology by mediating mechanisms associated with apoptosis and cell cycle. METHODS: Mature male Wistar rats (n = 24) were divided into 3 groups: control, T1D-induced (received 40 mg kg-1 streptozotocin) and insulin-treated T1D (Ins T1D; received 40 mg kg-1 streptozotocin and then treated 0.9 IU/100 gr of insulin for 56 days) (N = 8/group). Expression levels of intrinsic apoptosis pathways regulators (Bcl-2, Bax, Caspase-3 and p53) and core regulators of cell cycle machinery (Cyclin D1, Cdk-4 and p21) were determined in testicular tissue by immunohistochemistry (IHC) and RT-PCR techniques. The percentage of testicular apoptotic cells was evaluated by TUNEL staining. RESULTS: Our data shows that insulin treatment to T1D rats restored (P < 0.05) T1D-induced increased of caspase-3 and p53 expression in testis. Moreover, the testis of T1D rats treated with insulin exhibited increased expression of Cyclin D1 and cdk-4, and a reduced expression of p21 when compared with the expression in testis of T1D rats. Finally, insulin treatment could fairly control T1D-induced apoptosis. Accordingly, treatment of T1D rats with insulin led to a remarkable reduction (p < 0.05) in the percentage of apoptotic cells in the testis. CONCLUSIONS: Insulin treatment is able to restore the network expression of apoptosis and proliferation-related genes caused by T1D in the testis and via this mechanism, preserve the fertility of males.

The effectiveness of Rutin for prevention of surgical induced endometriosis development in a rat model.

Apoptosis and antioxidant mechanisms are pathways for the treatment of endometriosis (Endo). Rutin (Rtn) is an antioxidant flavonol that induces apoptosis. This study, for first time, was conducted to evaluate the effects of rutin on Endo through apoptosis and antioxidant mechanisms. The experimental Endo was induced in 24 rats and then the animals were subdivided into Endo-sole, 3000 and 6000 µg/kg rutin (Rtn-3000 and Rtn-6000) and vitamin C groups. After 4 weeks, the expression of Bcl2, Bax, anti Pro Caspase-9, cleaved Caspase-9, pro PARP, pro Cleaved PARP, Pro PARP, pro mTOR and mTOR were assessed by western blotting technique. The protein concentrations of malondialdehyde (MDA), total antioxidant capacity, and super oxide dismutase and gutathione peroxidase were also evaluated. TUNEL staining was also used for the detection of apoptosis. Caspase-9 and concentration of antioxidants were higher in the treated groups compared to Endo-sole group (P < 0.05). The results also showed that rutin decreased the expression of Bcl2 and MDA concentration (P < 0.05). The results for TUNEL staining showed that the animals treated with Rtn-6000 and vitamin C showed higher apoptosis. Rutin induces apoptosis by the expression of Bcl-2, Bax and caspase and also antioxidant activity by increasing antioxidants concentrations.

Testicular torsion and reperfusion: Germ cell DNA damage and development.

This study is aimed to analyse the cross-link between cyclin D1, cdk-4, p21, PCNA and DNA damage during different periods of reperfusion following experimental torsion in rats. Thirty mature male Wistar rats (N = 6) were used. Following 4 hr from torsion induction, the reperfusion was induced. Animals were subdivided into groups, including 4 hr torsion-induced (T1), 1 hr post-reperfusion (T2), 2 hr post-reperfusion (T3), 4 hr post-reperfusion (T4) and 8 hr post-reperfusion (T5) groups. The seminiferous tubules differentiation (TDI) and spermatogenesis indices were evaluated. The expressions of cyclin D1, cdk-4, p21and PCNA were analysed using Reverse Transcriptase-PCR (RT-PCR). Moreover, the cyclin D1+ , cdk-4+ , p21+ and PCNA+ cell numbers/mm2 of tissue were assessed through immunohistochemical staining. The testicular DNA fragmentation was analysed using TUNEL assay and DNA ladder test. Observations demonstrated that reperfusion significantly increased (p < 0.05) up-regulated the expressions of cyclin D1, cdk-4 and PCNA. The animals in T5 group showed diminished expression of p21 and represented diminished DNA fragmentation versus T1 group. In conclusion, minimum 8 hr post-reperfusion is needed to re-initiate necessary expressions of cyclin D1, cdk-4 and PCNA to restore cell cycling machinery and ameliorate torsion-induced DNA damage.