The decreased BMAL1 and P-AKT protein expression in the liver implied the association between circadian clock genes and the insulin-resistant state in PCOS (Fig. 2b), which was further supported by the disrupted rhythmic mRNA expression of Sirt1, Nampt, Glut4, and peroxisome proliferator activated receptor gamma (Pparg). This evidence concerns the gene BMAL1 and polycystic ovary syndrome.