Soy Isoflavones Improve the Spermatogenic Defects in Diet-Induced Obesity Rats through Nrf2/HO-1 Pathway

Abstract

Soy isoflavones (SIF) are biologically active compounds of non-steroidal and phenolic properties that are richly present in soybeans, which can reduce the body weight and blood lipids of obese animals. Recently, SIF have been reported to affect reproductive ability in obese male rats. However, the specific mechanism has not been well defined. The aim of the current study was to study the possible mechanisms for the effect of SIF administration on obesity induced spermatogenic defects. Obese rats model induced by high-fat diets were established and gavage treated with 0, 50,150 or 450 mg of SIF/kg body weight/day for 4 weeks. Here, our research shows that obesity resulted in spermatogenic degeneration, imbalance of reproductive hormone, testicular oxidative stress and germ cell apoptosis, whereas evidently recovery effects were observed at 150 and 450 mg/kg SIF. We also have discovered that 150 and 450 mg/kg SIF can activate Nrf2/HO-1 pathway in control of Bcl-2, BAX and cleaved caspase-3 expression with implications in antioxidant protection. Our study indicates the potential mechanism of SIF regulating spermatogenic function in obese rats, and provides a scientific experimental basis for the regulation of biological function of obese male reproductive system by SIF.

Ameliorating high-fat diet-induced sperm and testicular oxidative damage by micronutrient-based antioxidant intervention in rats

“…Testicular MDA, and glutathione content, catalase activity and expression of genes involved in oxidative stress were not significantly affected by the HFD feeding protocol in the current study. This is in contrast to previous studies reporting increased MDA content, expression of NFκB-p65, IL6 and TNF-α gene, decreased glutathione content, catalase activity and expression of Nrf2 and IL10 gene in testis of HFD-fed rodents [ 3 , 4 , 42 – 44 ]. However, the investigation of mRNA and protein expression of Nrf2, NFκB-p65, IL6, IL10 and TNF-α in seminal plasma would be of future interest given the altered cytokine levels in seminal plasma induced by HFD in a recent study [ 59 ].…”

“…Several rodent studies reported similar sperm and/or testicular oxidative damage as well as testicular weight upon feeding HFD [ 3 , 5 , 6 , 42 – 46 ] as we have demonstrated here. However, limited work has examined the effects of supplementation with the micronutrients used in this study (single or combined) on HFD-induced oxidative damage in both sperm and testis.…”

“…In developed countries including USA, UK and Australia, males are more affected by obesity than females [ 2 ]. Obesity in male rodents is closely linked with sperm and testicular oxidative damage, characterized by increased lipid peroxidation [ 3 , 4 ], reactive oxygen species (ROS) production and oxidative DNA damage [ 3 , 5 , 6 ]. Sperm oxidative DNA damage is increasingly being considered as one of the potential mechanisms underpinning paternal programming of offspring health in both human and rodents [ 7 , 8 ].…”

Protective Effect of Indole-3-Carbinol on Sperm Morphometric Alteration in a High-Fat Diet-Induced Obese Rat Model

“…Oxidative stress, which is the major reason for male infertility, has gained importance recently (5). Oxidative imbalance occurs when the balance between oxidant and antioxidant systems is impaired.…”

Evaluation of Hypoglycemic and Antioxidant Activities of Soybean Meal Products Fermented by Lactobacillus plantarum FPS 2520 and Bacillus subtilis N1 in Rats Fed with High-Fat Diet

“…Soy isoflavones administration normalized metabolic and immunological parameters via oxidative stress amelioration in female rats [ 27 ]. In male rats, soy isoflavones treatment (150 and 450 mg/kg of body weight per day for 4 weeks) showed a protective effect against HFD-induced testicular oxidative stress, cell apoptosis, and associated tissue damage [ 28 ]. As previously mentioned, soy isoflavone treatment supports the alleviation of exercise-induced oxidative stress, partially via enhancement of antioxidant enzyme activities [ 29 ].…”