Serum Bone-, Muscle- and Fat- Derived Factors Sclerostin, Irisin and Leptin Show Different Correlations With Body Composition and Bone Mineral Density in Chinese Men With Obesity: A Cross-Sectional Study.

AIMS: This study aimed to explore the interactions among sclerostin, irisin and leptin, as well as their associations with body composition and bone metabolism in Chinese men with obesity.

MATERIALS AND

METHODS

This study included 26 men with normal weight and 78 men with obesity. Body composition was measured using dual-emission X-ray absorptiometry. Subcutaneous fat, visceral fat and fat content in the liver and pancreas were determined by magnetic resonance. Serum sclerostin, irisin and leptin were detected using the Elisa assay.

RESULTS

Compared with men with normal weight, serum sclerostin, irisin and leptin levels as well as whole-body and spinal bone mineral density were increased, whereas pelvic bone mineral density was not different in men with obesity. Partial analysis showed that in men with obesity, serum sclerostin was positively correlated with bone mineral density but not with body composition; serum irisin was positively correlated with fat mass percent, negatively correlated with muscle mass percent, but not with bone mineral density; serum leptin was positively correlated with fat mass, while negatively associated with muscle mass and bone mineral density. Furthermore, body weight showed beneficial effects on whole-body and spinal bone, whereas central fat distribution exerted adverse effects on pelvic bone. Stepwise linear regression revealed that serum sclerostin and whole-body muscle mass were independent predictors of bone mineral density in the over-all cohort.

CONCLUSIONS

Serum sclerostin, irisin and leptin show distinct correlations with body composition and bone mineral density in men with obesity, which may partly reflect the complex effects of obesity on bone metabolism.