[Updates on Lifestyle-Related Diseases and Bone Metabolism. Effects of sclerostin on bone metabolism in patients with diabetes].

Sclerostin, a glycoprotein encoded by SOST gene and secreted from osteocyte, is known as an antagonist for bone formation induced in canonical Wnt/β-catenin signaling pathway by inhibiting receptor complex formation through binding to LDL receptor-related protein 5/6 (LRP 5/6) . From clinical symptoms observed in the patients with a loss-of-function mutation in LRP 6, disorder of that signal transduction pathway is considered as one of candidate molecular mechanism for the simultaneous occurrence of diabetes mellitus and osteoporosis. The serum sclerostin levels of diabetic patients as well as non-diabetic subjects are significantly and positively correlated with bone mineral density, which is the strongest determinant factor especially for diabetic patients. In addition, sclerostin concentrations are associated with prevalent vertebral fractures independent of bone mineral density as well as bone turnover, suggesting that elevated sclerostin levels reflect poor bone quality.