Mangiferin mitigates di-(2-ethylhexyl) phthalate-induced testicular injury in rats by modulating oxidative stress-mediated signals, inflammatory cascades, apoptotic pathways, and steroidogenesis

Abstract

Di-(2-ethylhexyl) phthalate (DEHP) is an endocrine disruptor that causes reproductive defects in male animal models. This study was conducted to explore the plausible modulatory effects of mangiferin (MF) against DEHP-induced testicular injury in rats. Thirty-two adult male albino rats were allocated into four groups. Two groups were given DEHP (2 g/kg/day, p.o) for 14 days. One of these groups was treated with MF (20 mg/kg/day, i.p) for 7 days before and 14 days after DEHP administration. A vehicle-treated control was included, and another group of rats was given MF only. Results revealed that MF treatment suppressed oxidative testicular injury by amplifying the mRNA expression of nuclear factor-erythroid 2 related factor-2 (Nrf2) and increasing hemoxygenase-1 (HO-1), glutathione, and total antioxidant capacity (TAC) levels. This treatment also enhanced superoxide dismutase activity, but it decreased malondialdehyde and nitric oxide levels. MF had an anti-inflammatory characteristic, as demonstrated by the downregulation of the mRNA of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). The content of tumor necrosis factor-alpha also decreased. MF modulated the apoptotic pathway by suppressing the mRNA of cytochrome c (Cyt c), Fas ligand content, Bax IHC expression, caspase-3 activity and cleaved caspase-3 IHC expression. It also upregulated the expression levels of heat-shock protein 70 (HSP70) and B-cell lymphoma 2. Moreover, MF upregulated the mRNA expression levels of HSP70 and c-kit and enriched the content of steroidogenic acute regulatory (StAR) protein, which were reflected in serum testosterone levels. This result indicated that MF played crucial roles in steroidogenesis and spermatogenesis. Besides, the activities of testicular marker enzymes, namely, acid and alkaline phosphatases, and lactate dehydrogenase, significantly increased. Histopathological observations provided evidence supporting the biochemical and molecular measurements. In conclusion, MF provided protective mechanisms against the DEHP-mediated deterioration of testicular functions partially through its antioxidant, anti-inflammatory, and anti-apoptotic properties. It also involved the restoration of steroidogenesis and spermatogenesis through the modulation of Nrf2/HO-1, NF-κB/Cyt c/HSP70, and c-Kit signaling cascades.

Keywords: DEHP; HSP70; Mangiferin; Nrf2; Testes; c-Kit.