Liu Wei, Zhang Yukun, Xia Ping, Li Shuai, Feng Xintong, Gao Yong, Wang Kun, Song Yu, Duan Zhenfeng, Yang Shuhua, Shao Zengwu, Yang Cao
Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Road, No. 1277,Wuhan 430022, China; Department of Orthopedics, First Hospital of Wuhan, Zhongshan Road, No.215, Wuhan 430022, China.
Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Road, No. 1277,Wuhan 430022, China.
Biomed Pharmacother. 2016 Oct;83:1414-1421. doi: 10.1016/j.biopha.2016.08.062. Epub 2016 Aug 30.
The precise role of interleukin-1 beta (IL-1β)-induced extracellular matrix degeneration in the pathogenesis of intervertebral disc degeneration (IDD) is currently unknown. Recent evidence has revealed that microRNAs (miRNAs) are associated with IDD, but their function in the extracellular matrix degradation of nucleus pulposus (NP) tissues is also poorly understood. The aim of this study was to evaluate the expression and functional role of miR-7 in IL-1β-induced disc degeneration. The expression level of miR-7 was investigated in degenerative NP tissues and in IL-1β-induced NP cells using quantitative reverse transcription-polymerase chain reaction amplification analysis. A dual-luciferase reporter assay was then utilized to determine whether growth differentiation factor 5 (GDF5) is a target of miR-7. Finally, mRNA and protein levels of known matrix components and of matrix degradation enzymes were determined to elucidate the function of miR-7 in IL-1β-induced disc degeneration. In this study, we found that miR-7 is highly expressed in human degenerative NP tissues and in IL-1β stimulated NP cells compared to normal controls. We also determined that GDF5 was a target of miR-7. Functional analysis showed that the overexpression of miR-7 significantly enhanced the IL-1β-induced extracellular matrix degeneration, whereas inhibition of miR-7 function by antagomiR-7 prevented NP cell detrimental catabolic changes in response to IL-1β. Additionally, the prevention of IL-1β-induced NP extracellular matrix degeneration by miR-7 silencing was attenuated by GDF5 siRNA. These findings suggest that miR-7 contributes to an impaired ECM in intervertebral discs through targeting GDF5 and miR-7 might therefore represent a novel therapeutic target for the prevention of IDD.
白细胞介素 -1β(IL -1β)诱导的细胞外基质退变在椎间盘退变(IDD)发病机制中的精确作用目前尚不清楚。最近的证据表明,微小RNA(miRNA)与IDD相关,但其在髓核(NP)组织细胞外基质降解中的功能也知之甚少。本研究的目的是评估miR -7在IL -1β诱导的椎间盘退变中的表达及功能作用。采用定量逆转录 - 聚合酶链反应扩增分析,研究退变NP组织和IL -1β诱导的NP细胞中miR -7的表达水平。然后利用双荧光素酶报告基因检测法确定生长分化因子5(GDF5)是否为miR -7的靶标。最后,测定已知基质成分和基质降解酶的mRNA及蛋白质水平,以阐明miR -7在IL -1β诱导的椎间盘退变中的功能。在本研究中,我们发现与正常对照相比,miR -7在人退变NP组织和IL -1β刺激的NP细胞中高表达。我们还确定GDF5是miR -7的靶标。功能分析表明,miR -7的过表达显著增强了IL -1β诱导的细胞外基质退变,而抗miR -7抑制miR -7功能可防止NP细胞对IL -1β产生有害的分解代谢变化。此外,GDF5 siRNA减弱了miR -7沉默对IL -1β诱导的NP细胞外基质退变的预防作用。这些发现表明,miR -7通过靶向GDF5导致椎间盘细胞外基质受损,因此miR -7可能是预防IDD的新治疗靶点。