Effects of microRNA-103a-3p on osteoporosis through tumor protein 53-regulated inhibitor of apoptosis 1/P53 / 解剖学报

ABSTRACT

Objective To investigate the efeects of microRNA(miR)-103a-3p regulates tumor protein 53-regulated inhibitor of apoptosis 1(TRIAP1)on osteoblast differentiation and bone mass in ovariectomized mice.Methods MC3T3-E1 cells were divided into normal group,miR-103a-3p-NC group,miR-103a-3p mimic group,miR-103a-3p mimic+TRIAP1-NC group,miR-103a-3p mimic+TRIAP1 mimic group.mRNA expression of miR-103a-3p,TRIAP1,P53 were detected by Real-time PCR;Cell proliferation and apoptosis were detected by MTT test and flow cytometry;cytoskeleton and mineralization of cells were detected by F-actin immunofluorescence staining and alizarin staining;alkaline phosphatase(ALP)activity was detected by ELISA.24 female mice were divided into sham group,osteoporosis(OP)group,miR-103a-3p antagonist-NC group,miR-103a-3p antagonist group(six in each group),extract bilateral ovaries to establish an OP model,sham group mice only isolated fat around ovarian tissue.mRNA expression of miR-103a-3p,TRIAP1,P53,ALP,osteocalcin(OCN),osteopontin(OPN)of bone tissue were detected;microCT detect bone mineral density(BMD),bone mineral content(BMC);haematoxylin eosin staining was used to observe pathological changes of bone tissue.Results After miR-103a-3p mimic was transfected into cells,the miR-103a-3p and P53 expression increased,TRIAP1 expression decreased,cell proliferation decreased,apoptosis increased,F-actin expression decreased,the number of calcium nodules decreased,and ALP enzyme activity decreased(P<0.01);however,after TRIAP1 mimic was additionally transfected into cells,the above result caused by miR-103a-3p mimics were significantly reversed(P<0.01).In OP group,the miR-103a-3p and P53 expression in bone tissue increased,the TRIAP1,ALP,OCN and OPN expression decreased,BMD and BMC were decreased,and bone tissue construct was damaged(P<0.05);in miR-103a-3p antagonist group,the miR-103a-3p and P53 expression in bone tissue decreased,TRIAP1,ALP,OCN,OPN expression increased,BMD and BMC increased,and bone tissue construct was improved(P<0.05).Conclusion MiRNA-103a-3p mediate TRIAP1/P53 to inhibit proliferation and mineralization of osteoblast,while miR-103a-3p antagonistic treatment reduce bone loss in OP mice.