Objective: Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder in women of reproductive age. Chemerin has recently been discovered as a novel adipokine associated with obesity and metabolic syndrome. Excessive autophagy activity and overexpression of autophagy-related genes in follicular granulosa cells are important mechanisms of PCOS. This study aimed to investigate the effect of chemerin on autophagy in PCOS.
Methods: A rat model of PCOS was established by subcutaneous injection of testosterone propionate under a high-fat diet. Expression levels of chemerin and its receptor CMKLR1 were determined by real-time polymerase chain reaction and western blot. Proliferation and apoptosis of human granulosa cells in vitro and expression of autophagy-related genes were examined using bafilomycin A1 (autophagy inhibitor) and Torin1 (autophagy inducer).
Results: Chemerin and CMKLR1 expression were significantly increased in the ovary in a rat model of PCOS. Ectopic expression of chemerin promoted the proliferation and inhibited the apoptosis of COV434 cells. Ectopic expression of chemerin also induced autophagy by inhibiting the phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway.
Conclusions: Chemerin and CMKLR1 were overexpressed in PCOS rats. Chemerin promoted autophagy through inhibiting the PI3K/Akt/mTOR pathway, and may provide a potential target and biomarker of PCOS.
Keywords: CMKLR1; COV434 granulosa cell; Polycystic ovary syndrome; autophagy; chemerin; mammalian target of rapamycin.