Stachyose ameliorates polycystic ovary syndrome through the gut–BAT axis by promoting Alistipes sp. proliferation

Polycystic ovary syndrome (PCOS) is associated with dysbiosis of the gut microbiota. Stachyose protects against various diseases caused by gut microbiota disturbances. We previously demonstrated that stachyose reduced testosterone levels and ameliorated estrous cycle disruption in PCOS rats. However, the mechanism was unclear. Here, stachyose treatment ameliorated ovarian dysfunction and insulin resistance (IR) in PCOS rats. Furthermore, stachyose promoted lipolysis in brown adipose tissue (BAT), which in turn enhanced BAT thermogenesis by indirectly upregulating thermogenic markers. 16S rDNA sequencing showed that stachyose significantly increased Alistipes sp . ( A.sp .) abundance in PCOS rats. In vitro, compared with lactose-treated group, stachyose promoted A.sp . proliferation in a time-dependent manner. Furthermore, oral gavage of A.sp . decreased serum testosterone, fasting glucose levels, body weight, and reshaped gut microbiota communities by increasing the abundance of beneficial microbes in PCOS rats. Importantly, A.sp . treatment increased ATGL, PGC-1α and UCP1 expression in the BAT of PCOS rats. This Suggest that stachyose ameliorates reproductive and metabolic disorders in PCOS through the gut-BAT axis: stachyose increases A.sp . abundance, triggering BAT lipolysis and driving UCP1-dependent thermogenesis and energy expenditure, ultimately mitigates both ovarian dysfunction and metabolic abnormalities. Collectively, these findings suggest that stachyose or A.sp . administration shows promise as a PCOS therapy.