title: MicroRNA-145 Mediates Steroid-Induced Necrosis of the Femoral Head by Targeting the OPG/RANK/RANKL Signaling Pathway.
abstract: OBJECTIVE
  To investigate the role of microRNA-145 (miR-145) in steroid-induced necrosis of the femoral head (SINFH) by evaluating its effects on the OPG/RANK/RANKL signaling pathway.
  
  
  METHODS
  A rat model of SINFH was constructed via injection of the lentiviral vector pLV-shRNA-miR-145. Pathological observation was performed via tartrate-resistant acid phosphatase (TRAP) staining, and serum OPG levels were detected by ELISA. The mRNA expression levels of miR-145, OPG, RANK and RANKL in THP-1 cells were assessed by RT-PCR, and the protein expression levels of OPG, RANK and RANKL were assessed by western blotting.
  
  
  RESULTS
  The expression of miR-145 in the lentivirus-mediated miR-145 group was significantly up-regulated compared with that in the control and normal groups (both P < 0.01). Serum OPG levels were decreased in SINFH rats compared with control and normal rats. The mRNA and protein expression levels of OPG in THP-1 cells decreased after transfection (all P < 0.05). By contrast, the mRNA and protein expression levels of RANK and RANKL in THP-1 cells increased after transfection (all P < 0.05). After transfection of 293T cells with an miR-145 overexpression vector, miR-145 expression in 293T cells increased significantly, while OPG mRNA and protein expression decreased significantly (all P < 0.05).
  
  
  CONCLUSIONS
  MiR-145 plays a role in the occurrence of SINFH by targeting the OPG/RANK/RANKL signaling pathway.
authors.affiliation: Department of Orthopedics, Wuxi People's Hospital, Wuxi 214000, China.
authors.forename: Ji-Jun
authors.initials: JJ
authors.lastname: Zhao
authors.affiliation: Department of Orthopedics, Wuxi People's Hospital, Wuxi 214000, China.
authors.forename: Zhao-Feng
authors.initials: ZF
authors.lastname: Wu
authors.affiliation: Department of Orthopedics, Wuxi People's Hospital, Wuxi 214000, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Orthopedics, Wuxi People's Hospital, Wuxi 214000, China.
authors.forename: De-Hong
authors.initials: DH
authors.lastname: Feng
authors.affiliation: Department of Orthopedics, Wuxi People's Hospital, Wuxi 214000, China.
authors.forename: Li
authors.initials: L
authors.lastname: Cheng
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D005271:Femur Head Necrosis / Q000209:etiology / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D053244:Osteoprotegerin / Q000235:genetics / Q000378:metabolism*; D053245:RANK Ligand / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D053246:Receptor Activator of Nuclear Factor-kappa B / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D013256:Steroids / Q000633:toxicity
chemical_list: C542511:MIRN145 microRNA, rat; D035683:MicroRNAs; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D013256:Steroids; C506032:Tnfrsf11b protein, rat