MiR-423-5p downregulates osteoblastic differentiation and cell viability by targeting SMAD3 in non-traumatic osteonecrosis

Ju Zheng,Xuegang Yan,Yun Zeng

doi:10.4314/tjpr.v20i3.18

Abstract

    Purpose: To investigate the potential role of miR-423-5p in osteoblastic differentiation of non-traumatic osteonecrosis of the femoral head (ONFH). Methods: MiR-423-5p levels in bone marrow samples from ONFH and osteoarthritis (OA) patients, respectively, were evaluated using quantitative (real-time) polymerase chain reaction (qPCR). Osteoblastic differentiation was monitored using Alizarin red S staining, while cell viability was determined by MTT assay in hMSC-BM. MiR-423-5p expression was also measured during osteoblastic differentiation. The underlying mechanisms were explored using TargetScan database, and a series of in vitro experiments was performed to confirm this. Results: MiR-423-5p levels were significantly upregulated in ONFH samples (p < 0.01) and miR-423-5p expression significantly increased in human mesenchymal stem cells-bone marrow (hMSC-BM) after bone morphogenetic protein 2 (BMP-2) treatment. Furthermore, miR-423-5p downregulated osteoblastic differentiation and suppressed cell viability. Furthermore, SMAD3 was observed to be a downstream target of miR-423-5p via bioinformatics analysis; further in vitro experiments confirmed this. Conclusion: MiR-423-5p downregulates osteoblastic differentiation and cell viability by targeting SMAD3 in non-traumatic osteonecrosis. Thus, MiR-423-5p may serve as a potential target for promoting osteoblastic differentiation in ONFH patients.   

Highlights

Osteonecrosis (ON) is a disease characterized by destruction of the blood supply of the femoral head [1]
Results of MTT assay demonstrated that viability of human mesenchymal stem cells-bone marrow (hMSC-BM) was significantly decreased with overexpression of miR-423-5p, and cell viability was significantly increased as a result of miR-423-5p knockdown (p < 0.01; Figure 2 B)
Fewer mineralized nodules were observed in hMSC-BM overexpressing miR-423-5p, and more mineralized nodules were observed by Alizarin red S staining with miR-423-5p knockdown (Figure 2 C)

Summary

Introduction

Osteonecrosis (ON) is a disease characterized by destruction of the blood supply of the femoral head [1]. Nontraumatic osteonecrosis of the femoral head (ONFH) is caused by increased intra-osseous pressure and abnormal formation of bone marrow fat, which subsequently lead to ischemia and osteocyte and bone-marrow cell death [3,4]. Treatment strategies, including core decompression and Previous studies showed that ONFH is associated with changes in bone marrow mesenchymal stem cell (MSC)-derived osteogenic differentiation [6]. This finding suggests the possibility that reduced capacity for MSC osteoblastic differentiation or MSC viability plays an important role in ONFH. Xu WH et al reported that miR-186-5p regulates osteoblast differentiation via decreased CXCL13 [10]. MiR-217 was implicated in the promotion of BMSC proliferation [11]

Objectives

Results

Conclusion