Ameliorative Potential of Nigella sativa (Black Seed) Ethanol Extract on Monosodium Glutamate-Induced Ovarian Damage in Sprague-Dawley Rats

Monosodium glutamate (MSG) is a commonly used food flavoring agent. This salt of glutamic acid plays a role in oxidative stress and tissue damage, including ovarian damage. Nigella sativa (NS) is used as a traditional medicine and has been shown to have multiple effects, including antioxidant and anti-inflammatory effects. This study aimed to investigate the potential of Nigella sativa seed (NSS) extract to protect against MSG-induced ovarian damage in Sprague-Dawley rats. The rats (n = 25) were grouped into four groups: A (control), B (400 mg/kg of MSG only), C (400 mg/kg of MSG + 100 mg/kg of NSS extract), and D (400 mg/kg of MSG + 200 mg/kg of NSS extract). Treatments were administered orally for 28 days. At the end of the experimental period, blood samples and ovaries were obtained to evaluate reproductive hormones and oxidative stress markers, and ovarian tissue was used for histopathological study. MSG-treatment significantly increased serum estrogen, FSH, LH, and ovarian malondialdehyde levels in the rats, but decreased ovarian glutathione levels. Treatment with the NSS extract significantly improved all these alterations. Histological findings from the MSG-treated rats showed evidence of follicular atresia, oocyte degeneration, vascular congestion, and inflammatory infiltration. The condition was remarkably improved in the NSS extract-treated rats. The findings of this study showed that the administration of MSG induces damage to the ovarian tissues and function. Nigella sativa seed extract was able to ameliorate the damage caused by MSG on the ovaries.