Adiponectin is abundantly present as a plasma protein, and exhibits various biological functions, such as regulating energy homeostasis and increasing insulin sensitivity in the liver and skeletal muscle. Circulating adiponectin includes both a full-length type (AN) and a globular type (gAN). Recent studies have demonstrated both a positive and negative action of adiponectin on bone formation, and it was thought that these different actions might be attributed to different forms of adiponectin. In this study we investigated the gene expression profiles of osteoblasts stimulated by AN or gAN.
Osteoblastic differentiation of a murine pro-osteoblastic cell line, MC3T3-E1 cells, was induced by ascorbic acid and β-glycerophosphate with or without recombinant murine gAN or AN. Gene expression profiles were obtained by DNA microarray analysis.
Stimulation of AN or gAN showed different gene expression profiles in osteoblasts. The different profiles of up-regulated gene expression in osteoblasts indicated that different forms of adiponectin act on osteoblastic differentiation through different pathways.