MicroRNAs play crucial roles in bone metabolism. In the present study, researchers at the Central South University, Changsha utilized LC Sciences’ miRNA microarray service and found that miR-148a is dramatically upregulated during osteoclastic differentiation of circulating CD14+ peripheral blood mononuclear cells (PBMCs) induced by macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor-κB ligand (RANKL). Overexpression of miR-148a in CD14+ PBMCs promoted osteoclastogenesis, while inhibition of miR-148a attenuated osteoclastogenesis. V-maf musculoaponeurotic fibrosarcoma oncogene homolog B (MAFB) is a transcription factor negatively regulating RANKL-induced osteoclastogenesis. MiR-148a directly targeted MAFB mRNA by binding to the 3’UTR and repressed MAFB protein expression. In vivo, this study showed that silencing of miR-148a using a specific antagomir inhibited bone resorption and increased bone mass in both ovariectomy (OVX) and sham-operated control mice. Furthermore, these results showed that miR-148a levels significantly increased in CD14+ PBMCs from lupus patients and resulted in enhanced osteoclastogenesis, which contributed to the lower BMD in lupus patients compared with normal control. Thus, this study provided a new insight into the roles of miRNAs in osteoclastogenesis, and contributed to a new therapeutic way for osteoporosis.
(A) Microarray assays were performed in the process of osteoclast differentiation. Red and green indicate high expression levels and low expression levels, respectively. Shown are the parts of the miRNAs that changed more than twofold. (B) The results of qRT-PCR were consistent with miRNA microarray. (C) Northern blot and qRT-PCR show miR-148a increased progressively with time during osteoclast differentiation. The level of miR-148a was normalized to U6 (n = 5).
miR-148a dramatically upregulated during osteoclast differentiation
miRNA Microarray Service – LC Sciences provides a miRNA expression profiling service using microarrays based on our in-house developed µParaflo® technology platform. We have standard arrays for all mature miRNAs of all species available in the latest version of the miRBase database (Release 21, July 2014). Our service is comprehensive and includes sample labeling, array hybridization, image data processing and in-depth data analysis. Two-three weeks after receiving your total RNA samples, we’ll send you both the raw and fully analyzed data. [Learn more…]
Reference
Cheng P, Chen C, He H, Hu R, Zhou H, Xie H, Zhu W, Dai R, Wu X, Liao E. (2012) MiR-148a regulates osteoclastogenesis via targeting MAFB. J Bone Miner Res 28(5), 1180-1190. [article]