Relationship between GDF15 level and bone metabolism in postmenopausal Chinese women.

Growth differentiation factor 15 (GDF15), is a newly identified member of the transforming growth factor-beta (TGF-β) family. It circulates as a 24.5-kDa homodimer. However, the function of GDF15 in bone metabolism remains unclear. In this study, we investigated the function of GDF15 in postmenopausal Chinese women. We measured serum GDF15 levels, bone mineral density (BMD), and bone turnover markers in 201 postmenopausal Chinese women ranging in age from 47 to 80 years. The concentration of serum GDF15 increased with age. Growth differentiation factor 15 levels displayed a negative correlation with lumbar spine, femoral neck, and total hip BMD. After adjusting for age, this association still existed and was significant. We identified age, GDF15, body mass index (BMI), and estradiol to be associated with BMD. Furthermore, we found that GDF15 levels had a significant negative relationship with bone alkaline phosphatase (BAP) levels; this relationship remained significant after adjustment. However, there was no significant correlation between levels of GDF15 and N-terminal telopeptide of type I collagen (NTX). For postmenopausal Chinese women, GDF15 is a negative predictor of BMD and has a negative correlation with bone formation biomarker BAP. In other words, GDF15 exerts negative regulation on bone mass by inhibiting bone formation.