TZDs such as pioglitazone and rosiglitazone have also been shown to be effective in improving insulin resistance and hyperandrogenemia, as well as ovulation rate and menstrual cyclicity in PCOS, and GLP-1 receptor agonists such as exenatide and liraglutide are novel therapeutic options for the treatment of obesity, particularly in women with PCOS who display impaired first- and second-phase insulin secretion (34). Here, INS is linked to obesity due to melanocortin 4 receptor deficiency.