Ocimum tenuiflorum L. extracts attenuate polycystic ovarian syndrome in letrozole treated female Wistar rats through modulation of iNOS, COX-2, IL-1β and TNF-α
摘要
Polycystic ovary syndrome (PCOS) is a prevalent endocrine abnormality affecting the women of child bearing age. PCOS markedly raises the chances of infertility, cardiovascular disease, and increased blood pressure. Ocimum tenuiflorum is known for its diverse roles and is used in Ayurveda to address a variety of pathological conditions. This study was done to scrutinize the role of inflammatory genes such as iNOS, COX-2, IL-1β, and TNF-α in letrozole-induced PCOS in female Wistar rats and to assess the therapeutic potential of Ocimum tenuiflorum extracts (OTM and OTEA) in restoring biochemical, histological, and molecular parameters through western blot and RT-PCR analyses. In this research, a total of sixty albino female Wistar rats were employed. Eighteen rats were designated for evaluating the toxicity of the plant extracts, and the remaining 42 were distributed randomly across seven groups. PCOS was induced by administering letrozole at a dosage of 1 mg/kg body weight, which was formed in 0.5% CMC solution, for a duration of 21 days. After induction (21 days), the rats received oral treatment with methanol (OTM) and ethyl acetate (OTEA) extracts of Ocimum tenuiflorum at the dose of 50 and 100 mg/kg body weight, while metformin (25 mg/kg body weight) was used as the positive control. The plant material underwent Soxhlet extraction, resulting in five separate extracts: hexane, ethyl acetate, ethanol, methanol, and aqueous. The in vitro anti-inflammatory efficacy of these extracts was assessed using protein denaturation, proteinase inhibition, erythrocyte membrane stabilization, and nitric oxide scavenging assays. An initial toxicity assessment was conducted to determine the safety of these extracts. Subsequently, in vivo evaluation included ovarian histology, serum biochemistry, and molecular analysis. Serum levels of sex hormones (testosterone and estradiol) were measured and the expression of inflammatory markers (iNOS, COX-2, TNF-α, and IL-1β) was examined using RT-PCR and western blotting. GC–MS analysis was performed to identify the compounds responsible for the pharmacological results. At 600 μg/mL concentration, the extracts of methanol and ethyl acetate showed notable anti-inflammatory effects, with inhibition of protein denaturation at 88.22 ± 1.52% and 82.51 ± 1.74% (P < 0.001), proteinase activity at 93.43 ± 1.6% and 89.03 ± 1.46% (P < 0.0001), erythrocyte membrane haemolysis at 89.61 ± 0.93% and 88.94 ± 0.92% (P < 0.0001), and nitric oxide activity at 88.34 ± 1.43% and 90.14 ± 1.2% (P < 0.0001), respectively. In vivo experiments using Wistar rats demonstrated that the oral administration of potent extracts did not produce any toxic effects. Post-treatment with OTM and OTEA extracts in PCOS-induced rats resulted in decreased serum testosterone and estrogen levels. A notable reduction in apparent follicular cysts was seen in the ovaries, along with a marked down-regulation in the expression levels of mentioned inflammatory genes suggesting potential anti-inflammatory and PCOS-modulating effects. Finally, GC–MS analysis confirmed the active compounds with robust anti-inflammatory efficacy. Our study showed that Ocimum tenuiflorum has the potential to attenuate PCOS by restoring hormonal levels and exerting anti-inflammatory effects.