S. boulardii CNCM I-745 a yeast probiotic attenuates PCOS-IR by suppressing LPS mediated inflammation in female rats

Chronic low-grade inflammation along with gut microbial dysbiosis, plays a crucial role in the development and progression of polycystic ovary syndrome (PCOS), the complex endocrine disorder associated with long-term metabolic consequences. S. boulardii is a promising yeast in the correction of gut dysbiosis. The present study aimed to test the efficacy of S. boulardii in managing PCOS in PCOS-IR rats induced by letrozole (1 mg/kg/day) and a high-fat diet (40%). Subsequently, the rats were co-administered with lyophilized S. boulardii at a dosage of 1.8 × 10⁷ CFU/kg/Day. The changes in organosomatic indices, plasma glucose, serum hormones, systemic LPS level, oxidative and inflammatory response, estrous cycle, ovarian histo-architecture, and mRNA expression of TNFα and NFκB were studied. The findings suggest that S. boulardii effectively interrupts the further progression of PCOS by correcting the metabolic endotoxemia, inflammation, and endocrine imbalances. An improved insulin sensitivity, along with the correction in serum LPS and body weight, was noted. This ameliorative effect was accompanied by the suppression of inflammatory cytokines (TNFα, IL-6, IL-1β, and NFκB). This probiotic was also found to exert antiandrogenic activity, regulating LH:FSH ratio, modulating the ovarian expression of CYP17A1 and NR3C4 remarkably, with further influence on serum estradiol level. Additionally, the corrected ovarian expression of SOD and catalase was observed with improved histomorphology. Present findings indicate the therapeutic potential of S. boulardii against PCOS, plausibly attributed to the correction of inflammation subsequent to its influence on the crosstalk within the metabolic and reproductive cascades associated with PCOS.