Abstract
Insulin resistance (IR) is one of the most common features of polycystic ovary
syndrome (PCOS), which is related to obesity. Whether increased
anti-Müllerian hormone (AMH) levels in PCOS are involved in the
pathogenesis of insulin resistance remains unclear. We investigated serum levels
of leptin and AMH along with basic clinical and metabolic parameters in 114 PCOS
patients and 181 non-PCOS women. PCOS patients presented higher fasting blood
glucose, insulin concentrations and Homeostatic Model Assessment of Insulin
Resistance (HOMA-IR) in addition to body mass index (BMI), lipids profiles and
hormone levels. HOMA-IR showed a positive correlation with BMI, AMH, leptin, and
low-density lipoprotein-cholesterol (LDL-c) levels. Interestingly, AMH is
strongly positively correlated with HOMA-IR and insulin concentrations for 1st
and 2nd hours of glucose treatment after fasting. Among PCOS women with
BMI≥25 kg/m2, high AMH level group showed an
increased HOMA-IR when compared to normal AMH level. However, among PCOS women
with normal BMI, women with high AMH presented an elevated fasting insulin
levels but not HOMA-IR when compared to normal AMH group. In vitro treatment of
isolated islet cells with high concentration of leptin (200 ng/ml) or
high leptin plus high concentration of AMH (1 ng/ml) significantly
enhanced insulin secretion. Importantly, co-treatment of AMH plus leptin
upregulates the expression of pro-apoptotic proteins, such as Bax, caspase-3,
and caspase-8 after incubating with a high level of glucose. These results
suggest that AMH may involve in the pathological process of pancreatic
β-cells in obese PCOS women.
Key words
anti-Mullerian hormone - insulin resistance - apoptosis - pancreatic islet cells