A comprehensive investigation on female Wistar rats examining the therapeutic potential of Pueraria tuberosa on letrozole-induced Polycystic ovarian syndrome

Abstract

Polycystic ovarian syndrome (PCOS) stands out as the most prevalent endocrine disorder affecting women of reproductive age with 5–10% of women experiencing its effects. Historically known as Stein-Leventhal syndrome, its pathology involves various irregularities including heightened androgen levels, insulin resistance, diminished estrogen and progesterone levels, and irregular gonadotropin levels. However, the drugs commonly used to treat PCOS come with multiple side effects and limited efficacy in targeting the disorder’s underlying pathology. Indian kudzu tubers, specifically Pueraria tuberosa (Willd.) DC. tubers are a valuable source of phytoestrogens such as puerarin, daidzein, biochanin-A, and formononetin. Phytoestrogens are natural compounds derived from plants that stimulate estrogenic activity through estrogen receptors (ERα and ERβ), thereby increasing estrogen levels. Hence, the objective of this research was to assess the impact of the ethanolic extract obtained from Pueraria tuberosa (Willd.) DC. on the ovarian steroidogenesis pathway in a rat model with induced PCOS using letrozole. To determine the hormonal parameters i.e. estrogen, testosterone, progesterone, follicle-stimulating hormone and luteinizing hormone level, as well as to evaluate body weight, ovarian weight, and histopathology of the ovary in female rats, we investigated a comprehensive investigation on female Wistar rats examining the therapeutic potential of Pueraria tuberosa on letrozole-induced PCOS. For this aim, animals were divided into six groups (n=6). Control group, untreated letrozole-induced PCOS group (1 mg/kg bwt) for 21 days, PCOS group treated with tuber extract of Pueraria tuberosa (Willd.) DC (100 200 and 400 mg/kg bwt) for 14 days, and PCOS group treated with clomiphene citrate (1 mg/kg bwt) for 14 days. Finally, body and ovarian weight, and hormonal assays (estrogen, testosterone, progesterone, follicle-stimulating hormone, and luteinizing hormone levels) were conducted. Histomorphometric ovarian evaluation of cystic follicles was determined. The ethanolic extract of Pueraria tuberosa (Willd.) DC. tuber exhibited a significant enhancement in both body weight and ovarian weight when compared with the PCOS-induced group. It positively influenced hormonal levels by increasing estrogen and progesterone while decreasing testosterone levels. In addition, the extract normalized the ratio of follicle-stimulating hormone and luteinizing hormone levels and assessed histomorphometric changes, leading to a reduction in cystic follicles. In summary, the ethanolic extract derived from the tuber of Pueraria tuberosa (Willd.) DC. demonstrates the potential to alleviate certain symptoms associated with polycystic ovary syndrome. This positive impact is attributed to its components, including puerarin, daidzein, biochanin-A, and formononetin, which exhibit estrogenic and antiandrogenic effects. Notably, in this study, doses of 200–400 mg/kg of the extract were identified as the most effective, suggesting their promise as a potential therapeutic intervention for PCOS.