Identification of candidate genes simultaneously shared by adipogenesis and osteoblastogenesis from human mesenchymal stem cells.

INTRODUCTION: In osteoporosis field, it had been clinically well established a given relationship between bone formation and lipid accumulation. Although numerous molecules had been well documented for adipogenesis and osteoblastogenesis (adipo-osteoblastogenesis), the reciprocal transcriptional regulation still remains to be explored.

MATERIAL AND METHODS: Here, we tried to identify the common candidate genes of adipocyte/osteoblastocyte differentiation at 3, 5, and 7 days using human mesenchymal stem cells (hMSCs) via RNA-Seq technique. By using RNA interference (RNAi), we further confirmed the function of candidate genes during adipo-osteoblastogenesis through Oil Red/Alizarin Red/alkaline phosphatase (ALPL) staining and qRT-PCR (quantitative real-time PCR).

RESULTS: The identified 275 significantly differentially expressed genes (DEGs), especially with the down-regulated genes most prevalent and PI3K-AKT signaling pathway mostly enriched, were simultaneously shared by both differentiation events. Using lentiviral system, we further confirmed that ANKRD1 (ankyrin repeat domain 1) promoted adipogenesis and inhibited osteoblastogenesis via RNA interference (RNAi), and IGF1 (insulin like growth factor 1) simultaneously facilitated adipo-osteoblastogenesis on the base of gene expression of biomarkers and cellular phenotype property.

CONCLUSION: This study would provide the potential molecular switches to control the adipocyte/osteoblastocyte balance or hMSCs fate choices and clues to screen the study and therapy targets of metabolic bone disease osteoporosis.