Testis metal toxicity remediation by agro-food waste: evidence of a protective effect of melon seed husk extract Cucumeropsis mannii silica nanoparticles on gonadotropin and sex steroid hormones

Abstract

Male fertility is strongly affected by the overexpression of free radicals induced by heavy metals. The aim of this study was to produce nanoparticles from the agro-food waste, Cucumeropsis mannii melon seed husk extract (MSHE), whose burned seeds in Nigeria become incorporated into the soil contributing to pollution; and to propose a potential remediation biomarker adoptable to a metal-exposed animal model. Sol–gel precipitated melon husk silica nanoparticles were characterized by spectrophotometric and X-ray diffraction analysis. Biochemical and histopathological tests were performed on male albino rats divided into 8 groups orally exposed to Ni, Al, and Ni/Al both alone as well as co-administrated with MSHE at several dosages. Metal exposure reduced levels of plasma gonadotropin hormones follicle-stimulating hormone (FSH), Luteinizing Hormone (LH), and the sex steroid hormone testosterone, but MSHE co-administration increased them. MSHE treatment alone also raised FSH and LH levels compared to the metal-exposed groups. Plasma gonadotropin prolactin (PRL) levels were higher in each group examined, whereas MSHE co-administration significantly lowered them. Additionally, MSHE treatment alone exhibited lower PRL levels than the mixture-exposed groups and increased testosterone levels. Plasma hormonal results were confirmed by regeneration of testis architecture, testis lipid peroxidation decreases, and testis antioxidant increases. Use of agro-food waste nanoparticles has significant implications as evaluated with male albino rat plasma hormone levels. MSHE may ameliorate Ni–Al mixture-induced testicular toxicity and may be a useful future therapeutic tool.

Graphical abstract