Overexpression of miR-182 inhibits ossification of ligamentum flavum cells by targeting NAMPT

Qiang Zhang; Yifei Shen; Yuqing Jiang; Shujie Zhao; Dong Zhou; Nanwei Xu

doi:10.1016/j.yexcr.2018.03.008

Overexpression of miR-182 inhibits ossification of ligamentum flavum cells by targeting NAMPT

Exp Cell Res. 2018 Jun 15;367(2):119-131. doi: 10.1016/j.yexcr.2018.03.008. Epub 2018 Mar 27.

Authors

Qiang Zhang¹, Yifei Shen², Yuqing Jiang², Shujie Zhao², Dong Zhou³, Nanwei Xu⁴

Affiliations

¹ Department of Orthopaedics, The Affiliated Changzhou No. 2 People's Hospital with Nanjing Medical University, Changzhou, Jiangsu, China; Department of Spine Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China.
² Department of Orthopaedics, The Affiliated Changzhou No. 2 People's Hospital with Nanjing Medical University, Changzhou, Jiangsu, China.
³ Department of Orthopaedics, The Affiliated Changzhou No. 2 People's Hospital with Nanjing Medical University, Changzhou, Jiangsu, China. Electronic address: zhoudong1012@hotmail.com.
⁴ Department of Orthopaedics, The Affiliated Changzhou No. 2 People's Hospital with Nanjing Medical University, Changzhou, Jiangsu, China. Electronic address: nwxu_no2@163.com.

PMID: 29601800
DOI: 10.1016/j.yexcr.2018.03.008

Abstract

Ossification of the ligamentum flavum (OLF) is a debilitating disease resulting from the development of ectopic bone formation, which leads to the compression of the spinal cord. Nicotinamide phosphoribosyltransferase (NAMPT) was found to be upregulated and microRNA-182 (miR-182) was downregulated in OLF tissue. We investigated the effects of NAMPT and miR-182 expression in OLF cells and the influence on proteins associated with osteogenic differentiation. MiR-182 overexpression inhibited NAMPT, RUNX2, OCN and OPN mRNA and protein expression in OLF cells. Alkaline phosphatase (ALP) assay and Alizarin red staining confirmed reduced levels of osteogenic differentiation and mineralized nodule formation. Knockdown of NAMPT and the NAMPT inhibitor FK866 also inhibits RUNX2, OCN and OPN mRNA expression and protein levels, whereas overexpression of NAMPT promotes the expression of RUNX2, OCN and OPN and the generation of bone nodules. Dual-luciferase reporter assays revealed that miR-182 directly targets NAMPT and downregulates its expression. Transfection of OLF cells with miR-182 downregulated NAMPT and suppressed the regulation of RUNX2, OCN, and OPN by NAMPT overexpression. Overall, these data demonstrate that miR-182 suppresses OLF by downregulating NAMPT.

Keywords: Ligamentum flavum; NAMPT; OCN; OPN; Ossification; RUNX2; miR-182.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cells, Cultured
Cytokines / antagonists & inhibitors
Cytokines / genetics*
Cytokines / metabolism
Gene Expression Regulation
Humans
Ligamentum Flavum / pathology*
MicroRNAs / metabolism*
Nicotinamide Phosphoribosyltransferase / antagonists & inhibitors
Nicotinamide Phosphoribosyltransferase / genetics*
Nicotinamide Phosphoribosyltransferase / metabolism
Ossification, Heterotopic / genetics*
Ossification, Heterotopic / metabolism
Ossification, Heterotopic / pathology

Substances

Cytokines
MicroRNAs
Mirn182 microRNA, human
Nicotinamide Phosphoribosyltransferase
nicotinamide phosphoribosyltransferase, human