Antiapoptotic and antioxidant capacity of phytochemicals from Roselle (Hibiscus sabdariffa) and their potential effects on monosodium glutamate-induced testicular damage in rat.

Monosodium glutamate (MSG), common flavor enhancer and feed additive, causes male reproductive dysfunction. However, Roselle tea, popular Hibiscus sabdariffa (HS) beverage, has a controversial effectiveness on male fertility. Therefore, the current study aimed to investigate either the adverse effect of aqueous HS extract (HSE) on the testicle or its potential ameliorative role including some stress markers, biochemical and immunohistochemical expressions in rats subjected to MSG. Here, the animals were divided into four groups that were given distilled water, HSE, MSG, and HSE + MSG respectively via gavage. After 6 weeks from the beginning of experiment, blood samples were collected for hormonal analysis. Additionally, testicular specimens were excised and processed for oxidative/antioxidant parameters determination, histological examination, and immunohistochemical evaluation of Bax and PCNA positive spermatogenic cells. Preliminary phytochemical analyses as well as antioxidant capacity of the HSE were tested. Our results revealed a strong inhibitory activity of the HSE phytochemical constituents against DPPH radical. MSG group revealed a significant decrease of testosterone, LH, FSH, and antioxidant parameters with elevated MDA compared with control and HSE groups. Additionally, an alteration of the testicular histo-architecture was observed among MSG group along with increased Bax and decreased PCNA positive cells. Meanwhile, the HSE showed a potent protective effect against testicular damage as well as oxidative stress induced by MSG. On the whole, our findings provide evidence that HSE can ameliorate MSG-induced testicular toxicity via induction of cell proliferation along with reduction of oxidative stress and cellular apoptosis in adult rat that attributed to the antioxidant and antiapoptotic effects of its phytochemical constituents.