Candidate genes responsible for lipid droplets formation during adipogenesis simultaneously affect osteoblastogenesis.

Introduction: With cellular lipid storage varying, the balance between lipid intake and lipid degradation was a must to keep healthy and determined the level of lipid droplets. Although lipid droplets accumulation had been well demonstrated in adipocytes, gene expression profiling and gene function during adipogenesis and osteoblastogenesis remain unknown.

Material and methods: Here, this work profiled gene transcriptional landscapes of lipid droplets formation during adipogenesis from human mesenchymal stem cells (hMSCs) using RNA-Seq technique. By using RNA interference (RNAi) we investigated the function of candidate genes during adipogenesis and osteoblastogenesis using Oil Red/Alizarin Red/alkaline phosphatase (ALPL) staining and qRT-PCR (quantitative real-time PCR).

Results: Eleven differentially up-regulated genes associated with lipid droplets formation were identified at 3, 5, 7, 14, 21, and 28 days during adipogenesis. Unexpectedly, APOB per se inhibiting adipogenesis weakened osteoblastogenesis and METTL7A facilitating adipogenesis negligibly inhibited osteoblastogenesis according to the phenotypic characterization of adipocytes and osteoblasts and transcriptional condition of biomarkers through lentivirus transfection assays.

Conclusions: The establishment of the gene transcriptional profiling of lipid droplets formation would provide the molecular switches of hMSCs cell fate determination and the study targets for fat metabolic diseases.