Increased GPC4 and clusterin associated with insulin resistance in patients with PCOS.

The aim of the study was to investigate the changes in serum glypican 4 (GPC4) and clusterin (CLU) levels in patients with polycystic ovary syndrome (PCOS) as well as their correlation with sex hormones and metabolic parameters. A total of 40 PCOS patients and 40 age-matched healthy women were selected. Serum GPC4 and CLU levels were compared between the PCOS and control groups, and binary logistic regression was used to analyze the relative risk of PCOS at different tertiles of serum GPC4 and CLU concentrations. Stepwise linear regression was used to identify the factors influencing serum GPC4 and CLU levels in PCOS patients. Serum GPC4 (1.82 ± 0.49 vs 1.30 ± 0.61 ng/mL, P < 0.001) and CLU (468.79 ± 92.85 vs 228.59 ± 82.42 µg/mL, P < 0.001) were significantly higher in PCOS patients than in healthy women after adjustment for body mass index (BMI). In the PCOS group, serum GPC4 was positively correlated with follicle-stimulating hormone, fasting plasma glucose (FPG), fasting insulin (FINS), homeostatic model assessment of insulin resistance (HOMA-IR), triglyceride, and CLU (P < 0.05), whereas serum CLU was positively correlated with BMI, FPG, FINS, and HOMA-IR (P < 0.05). Multiple stepwise linear regression analysis showed that HOMA-IR was independently associated with serum GPC4, and BMI and HOMA-IR were independently associated with CLU (P < 0.05). Serum GPC4 and CLU levels were significantly higher in PCOS patients than in healthy women, suggesting that GPC4 and CLU may be markers associated with insulin resistance in women with PCOS.