Early Serum MicroRNA Profile Analysis After One Month's Intermittent Administration Of PTH 1-34 In Postmenopausal Osteoporosis Patients

ObjectiveOsteoporosis is a complex and degenerative bone metabolism disease characterized by the reduced bone mass and deteriorated microarchitecture of bone tissue,leading to compromised bone strength and an increase in the risk of fractures.At present,PTH 1-34 is the most promising drug to promote bone formation in the treatment of osteoporosis,but its bone anabolic mechanism remains to be further studied.We aimed to investigate the early serum microRNA(miRNA)expression profile after one month's intermittent PTH 1-34 treatment of postmenopausal osteoporosis(PMOP)patients,and explore the roles of differential miRNAs in the bone anabolic action and may provide a new basis for the osteoporosis treatment with PTH 1-34.MethodThe subjects enrolled in this study were confirmed postmenopausal osteoporosis patients,average age 62.75 ± 3.3 years,between March 2016 to March 2017 at Tianjin Medical University General Hospital.Patients were treated with daily subcutaneous injections of PTH 1-34 20 ?g,plus daily oral calcium 1000 mg and vitamin D 800 IU since at least three months before enrollment and throughout the study.Blood samples were taken at baseline(before)and after one month's treatment to perform miRNA microarray analysis and qRT-PCR,and measure the levels of specific serum bone-related markers: serum calcium,25-hydroxyvitamin D(25(OH)D),osteocalcin(OC),serum C-telopeptide of type 1 collagen(CTX)and procollagen I N-terminal propeptide(PINP).Target gene prediction of the differential miRNA was performed by using PicTar,miRanda,and TargetScan.The biological functions and corresponding signaling pathways of the differential miRNA were investigated by Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis.ResultAfter one month's PTH 1-34 treatment,as bone formation markers(OC and PINP)were obviously increased,total five significantly differential miRNA(hsa-miR-150-5p,hsa-miR-7855-5p,hsa-miR-765,hsa-miR-4484 and hsa-miR-6510-5p)were identified in serum specimens of PMOP patients.Quantitative real-time polymerase chain reaction(qRT-PCR)confirmed that the expression levels of the three differential miRNA(hsa-miR-150-5p,hsa-miR-7855-5p and hsa-miR-765)were in accordance with the microarray result.Bioinformatics analysis of differentially expressed miRNA target genes by GO and KEGG database.The result of GO analysis show that the function of the target gene is mainly involved in nervous system development,positive regulation of cell migration,protein binding,cell adhesion,etc.KEGG annotation revealed a series of pathways related to osteogenesis,including calcium,Wnt,Ras,MAPK signaling pathways,etc.ConclusionAfter one month's PTH 1-34 treatment,both the serum levels of bone formation markers and the three differential miRNA(hsa-miR-150-5p,hsa-miR-7855-5p and hsa-miR-765)were significantly increased in PMOP patients.The bioinformatic analyses suggested that the three differential miRNA might play important roles in the PTH 1-34 bone anabolic action for the treatment of PMOP.