Open AccessMicroRNA-186 improves fracture healing through activating the bone morphogenetic protein signalling pathway by inhibiting SMAD6 in a mouse model of femoral fracture
Author(s) -
C Wang,
Zheng Gf,
Xiaolong Xu
Publication year - 2019
Publication title -
bone and joint research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.639
H-Index - 31
ISSN - 2046-3758
DOI - 10.1302/2046-3758.811.bjr-2018-0251.r1
Subject(s) - femoral fracture , femur , bone morphogenetic protein , microrna , bone healing , femur fracture , gene silencing , microbiology and biotechnology , smad , messenger rna , anatomy , biology , signal transduction , medicine , surgery , gene , genetics
Objectives MicroRNAs (miRNAs) have been reported as key regulators of bone formation, signalling, and repair. Fracture healing is a proliferative physiological process where the body facilitates the repair of a bone fracture. The aim of our study was to explore the effects of microRNA-186 (miR-186) on fracture healing through the bone morphogenetic protein (BMP) signalling pathway by binding to Smad family member 6 (SMAD6) in a mouse model of femoral fracture.Methods Microarray analysis was adopted to identify the regulatory miR of SMAD6. 3D micro-CT was performed to assess the bone volume (BV), bone volume fraction (BVF, BV/TV), and bone mineral density (BMD), followed by a biomechanical test for maximum load, maximum radial degrees, elastic radial degrees, and rigidity of the femur. The positive expression of SMAD6 in fracture tissues was measured. Moreover, the miR-186 level, messenger RNA (mRNA) level, and protein levels of SMAD6, BMP-2, and BMP-7 were examined.Results MicroRNA-186 was predicted to regulate SMAD6. Furthermore, SMAD6 was verified as a target gene of miR-186. Overexpressed miR-186 and SMAD6 silencing resulted in increased callus formation, BMD and BV/TV, as well as maximum load, maximum radial degrees, elastic radial degrees, and rigidity of the femur. In addition, the mRNA and protein levels of SMAD6 were decreased, while BMP-2 and BMP-7 levels were elevated in response to upregulated miR-186 and SMAD6 silencing.Conclusion In conclusion, the study indicated that miR-186 could activate the BMP signalling pathway to promote fracture healing by inhibiting SMAD6 in a mouse model of femoral fracture. Cite this article: Bone Joint Res 2019;8:550–562.