title: Glucocorticoid inhibits cell proliferation in differentiating osteoblasts by microRNA-199a targeting of WNT signaling.
abstract: The inhibition of osteoblast proliferation by glucocorticoids (GCs) is very important in the etiology of GC-induced osteoporosis. The mechanisms of this process are still not fully understood. The results of recent studies have indicated an important role for microRNAs in GC-mediated responses in various cellular processes, including cell proliferation and apoptosis. Therefore, we developed the hypothesis that these regulatory molecules might be involved in GC-decreased osteoblast proliferation. Western blotting, quantitative real-time PCR, cell proliferation assays, and luciferase assays were employed to investigate the role of miRNAs in GC-inhibited osteoblast proliferation. microRNA-199a-5p was significantly increased in osteoblasts treated with dexamethasone (Dex). To delineate the role of microRNA-199a-5p, we silenced and overexpressed microRNA-199a-5p in osteoblasts. We found that overexpressing microRNA-199a-5p remarkably increased the inhibition effect of Dex on osteoblast proliferation, and depleting microRNA-199a-5p significantly attenuated Dex-inhibited osteoblast proliferation. Results of mechanistic studies indicated that microRNA-199a-5p inhibited FZD4 and WNT2 expression through a microRNA-199a-5p binding site within the 3'-UTR of FZD4 and WNT2. The post-transcriptional repression of FZD4 and WNT2 were further confirmed by luciferase reporter assay. These results indicated that microRNA-199a-5p may play a significant role in GC-inhibited osteoblast proliferation by regulating the WNT signaling pathway.
authors: Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China.
authors: Changgui
authors: C
authors: Shi
authors: Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China.
authors: Ping
authors: P
authors: Huang
authors: Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China.
authors: Hui
authors: H
authors: Kang
authors: Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China.
authors: Bo
authors: B
authors: Hu
authors: Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China.
authors: Jin
authors: J
authors: Qi
authors: Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China.
authors: Min
authors: M
authors: Jiang
authors: Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China.
authors: Hanbing
authors: H
authors: Zhou
authors: Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China guolei607@126.com.
authors: Lei
authors: L
authors: Guo
authors: Shanghai Key Laboratory for Bone and Joint DiseasesShanghai Institute of Orthopaedics and Traumatology, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No.197, The Second Ruijin Road, Luwan District, Shanghai 200025, People's Republic of ChinaDepartment of OrthopedicsChangzheng Hospital, The Second Military Medical University of China, Shanghai, People's Republic of China.
authors: Lianfu
authors: L
authors: Deng
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002454:Cell Differentiation; D049109:Cell Proliferation; D003907:Dexamethasone / Q000494:pharmacology*; D005260:Female; D051157:Frizzled Receptors / Q000235:genetics / Q000378:metabolism; D005938:Glucocorticoids / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000502:physiology*; D010006:Osteoblasts / Q000502:physiology*; D034622:RNA Interference; D015854:Up-Regulation; D060449:Wnt Signaling Pathway; D051154:Wnt2 Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D051157:Frizzled Receptors; C498581:Fzd4 protein, mouse; D005938:Glucocorticoids; D035683:MicroRNAs; C534780:Mirn199 microRNA, mouse; D051154:Wnt2 Protein; D003907:Dexamethasone
keywords: WNT signaling; glucocorticoids; microRNA-199a-5p; osteoblasts; proliferation