Study On The Damage And Mechanism Of Soy Isoflavones On Spermatogenesis In Diet-Induced Obese Rats

Objective: A number of studies have demonstrated that soy isoflavones(SIF)can treat obesity-related diseases,but their effects on obese male reproductive systems are unclear.Therefore,this study aimed to study the effect and mechanism of SIF on spermatogenesis induced by high-fat diet in obese rats,and provide scientific clinical experimental basis for improving the biological function of SIF to regulate obese male reproductive system.Methods: An obese model was established with different doses(50,150,450 mg/kg · BW)of SIF for 4 weeks.The morphology of rat testis was observed by HE staining and PAS staining.The expression of Cleaved Caspase-3 protein in testis was observed by immunohistochemical staining.The content of plasma reproductive hormone and testis 8-OHd G was detected by ELISA.MDA and testicular tissue were detected by UV spectrophotometry.GSH content,T-AOC level,SOD,GSH-PX and CAT activity.The expression levels of SOD3,SOD2,GSH-PX,Nrf2,HO-1,bcl-2,BAX and Caspase-3 m RNA were detected by real-time fluorescent quantitative PCR.Nrf2,HO-1,bcl-2,BAX and Cleaved Caspase were detected by immunoblotting.3 protein expression levels.Results:(1)After SIF intervention,the weight of obese rats was significantly reduced in a timeand dose-dependent manner.Low dose of SIF significantly decreased plasma HDL-C levels in obese rats(P<0.05).High dose of SIF significantly decreased plasma TC,TG and LDL-C levels in obese rats(P<0.05).(2)SIF significantly increased plasma FSH,LH and Gn RH levels in obese rats(P<0.01)in a dose-dependent manner.SIF significantly reduced plasma E2 levels in obese rats(P<0.01).Medium and high doses of SIF significantly increased plasma T levels in obese rats(P<0.01).(3)Low dose of SIF significantly increased testicular absolute weight and sperm motility in obese rats(P<0.01).The medium and high doses of SIF significantly increased the absolute weight,sperm density and sperm motility of obese rats,and decreased the rate of sperm deformity(P<0.05).(4)Medium and high doses of SIF showed better improvement of testicular histological damage in obese rats;after medium and high doses of SIF intervention,the number of germ cells in the seminiferous tubules of obese rats,the diameter of seminiferous tubules and the stage of VII to VIII The number of seminiferous tubules was significantly higher than that of the obese group(P<0.05).(5)Oxidative stress index results: SIF reduced MDA and 8-OHd G content in testis of obese rats.SIF increased the SOD activity of testis in obese rats.The medium and highdoses of SIF significantly increased the T-AOC level,GSH-PX and CAT activity in the testis of obese rats(P<0.05).(6)SIF significantly increased the expression of SOD3,SOD2 and HO-1 m RNA in the testis of obese rats(P<0.05),and the m RNA level of HO-1 gene in obese rats increased with the intervention dose of soy isoflavones.,dose dependent.The medium and high doses of SIF significantly increased the expression of GSH-PX1,Nrf2 and Bcl-2 m RNA in the testis of obese rats(P<0.01).SIF significantly decreased the expression of Caspase-3 and BAX m RNA in obese rats(P<0.01).The m RNA level of BAX gene in obese rats decreased with the increase of the dose of soy isoflavones in a dose-dependent manner.(7)SIF significantly increased the protein content of Nrf2,HO-1 and Bcl-2 in the testis of obese rats(P<0.01),and these changes were accompanied by a significant decrease in the content of BAX and cleaved caspase-3 protein(P < 0.01).Conclusion: Spermogenesis in obese rats is inhibited,reproductive endocrine becomes disordered,oxidative damage in testis tissue and germ cell apoptosis.SIF increases Nrf2/HO-1 and its downstream by affecting reproductive hormone and participating in oxidative stress and apoptosis of SOD3,SOD2,GSH-PX,Nrf2,HO-1,bcl-2,BAX and Caspase-3 m RNA expression The expression of antioxidant enzymes and anti-apoptotic factor Bcl-2,decreased the expression of proapoptotic factors caspase-3 and BAX to improve oxidative damage and germ cell apoptosis,thereby maintaining normal spermatogenesis in the testes.