Relationship Between the Abnormal Expression of PPARs and Insulin Resistance in Uterus of Rats with Polycystic Ovary Syndrome and Insulin Resistance

Abstract

ObjectiveTo investigate the relationship between abnormal expression of peroxisome proliferator-activated receptors (PPARs) and insulin resistance in the uterine tissues of rats with polycystic ovary syndrome and insulin resistance (PCOS-IR).MethodsForty female SD rats were randomly divided into normal control and PCOS-IR model groups. PCOS-IR models were established by subcutaneous injection of insulin and human chorionic gonadotropin (INS+hCG) method, and rats in the normal control group were injected with equal amounts of normal saline. Fasting insulin (FINS) and fasting plasma glucose (FPG) levels were measured by enzyme-linked immunosorbent assay (ELISA), and the insulin resistance index (HOMA-IR) was calculated. Uterine tissues of rats were stained with hematoxylin-eosin (HE), PPARs were detected by immunohistochemistry, and the expressions of PPARs, insulin receptors (IRS), glucose transporter 4 (GLUT-4), and insulin-like growth factor-1 (IGF-1) were detected by Western blotting.ResultsFPG and FINS levels and HOMA-IR in the model group were significantly higher than those in the normal control group (P 0.05). Western blotting results showed that the expression of PPARα, PPARγ, IRS, and GLUT-4 in the rat uterus of the model group was significantly lower than that of the normal control group (P < 0.05), while the expression of IGF-1 was higher than that of the normal control group (P < 0.05).ConclusionThe expression of IRS and GLUT-4 is down-regulated and the expression of IGF-1 is up-regulated in the uterine tissue of PCOS-IR rats. The existence of IR is confirmed in the uterine tissue of PCOS-IR rats, and it may be related to the down-regulation of PPARα and PPARγ expression in the uterine tissues.

Keywords

• peroxisomal proliferator-activated receptors
• polycystic ovary syndrome
• insulin resistance
• uterine tissue
• rat