Increased adipsin is associated with carotid intima media thickness and metabolic disturbances in polycystic ovary syndrome

CONTEXT

Adipsin, a protein secreted mainly from the adipose tissue, is a structural homologous of complement factor D, a rate-limiting enzyme of the alternative complement system. Growing evidence suggests that the alternative complement system plays a role both in the regulation of energy homoeostasis and in the atherosclerosis. Polycystic ovary syndrome (PCOS) is a reproductive and metabolic disease.

OBJECTIVE

To ascertain whether circulating adipsin levels are altered in women with PCOS, and whether there is an association between adipsin and metabolic parameters or carotid intima media thickness (CIMT).

PARTICIPANTS

A total of 144 women with PCOS and 144 age- and BMI-matched controls without PCOS were recruited for this cross-sectional study.

MAIN OUTCOME MEASURES

Circulating adipsin levels were measured using ELISA. Metabolic, hormonal parameters and CIMT were also determined.

RESULTS

Adipsin levels were significantly elevated in women with PCOS compared with controls (91·52 ± 14·11 vs 60·31 ± 9·71 ng/ml, P < 0·001). Adipsin positively correlated with BMI, homoeostasis model assessment of insulin resistance (HOMA-IR), free testosterone, high-sensitivity C-reactive protein (hs-CRP) and CIMT in both groups. Multivariate logistic regression analyses revealed that the odds ratio for PCOS was 3·25 for patients in the highest quartile of adipsin compared with those in the lowest quartile (OR=3·25, 95% CI=2·64-4·00, P = 0·016). Our findings further indicate that BMI, HOMA-IR, hs-CRP and free testosterone are independent factors influencing serum adipsin levels and that adipsin is an independent predictor for CIMT.

CONCLUSION

Circulating adipsin levels are significantly higher in women with PCOS, and the peptide is closely related to increased cardiovascular risk and metabolic disturbances.

Elevated circulating levels of betatrophin are associated with polycystic ovary syndrome

Betatrophin is a newly identified hormone determined to be a potent inducer of pancreatic beta cell proliferation in response to insulin resistance in mice. Polycystic ovary syndrome (PCOS) is an inflammatory-based metabolic disease associated with insulin resistance. However, no evidence is available indicating whether betatrophin is involved in women with PCOS. The objective of this study was to ascertain whether betatrophin levels are altered in women with PCOS. This study was conducted in secondary referral center. This cross-sectional study included 164 women with PCOS and 164 age- and BMI-matched female controls. Circulating betatrophin levels were measured using ELISA. Metabolic and hormonal parameters were also determined. Circulating betatrophin levels were significantly elevated in women with PCOS compared with controls (367.09 ± 55.78 vs. 295.65 ± 48.97 pg/ml, P < 0.001). Betatrophin levels were positively correlated with insulin resistance marker homeostasis model assessment of insulin resistance (HOMA-IR), free-testosterone, high-sensitivity C-reactive protein (hs-CRP), atherogenic lipid profiles, and BMI in PCOS. Multivariate logistic regression analyses revealed that the odds ratio for PCOS was 2.51 for patients in the highest quartile of betatrophin compared with those in the lowest quartile (95 % CI 1.31-4.81, P = 0.006). Multivariate regression analyses showed that HOMA-IR, hs-CRP, and free-testosterone were independent factors influencing serum betatrophin levels. Betatrophin levels were increased in women with PCOS and were associated with insulin resistance, hs-CRP, and free-testosterone in these patients. Elevated betatrophin levels were found to increase the odds of having PCOS. Further research is needed to elucidate the physiologic and pathologic significance of our findings.