title: The Angiogenic Effect of microRNA-21 Targeting TIMP3 through the Regulation of MMP2 and MMP9.
abstract: microRNAs are a novel set of small, non-protein-coding nucleotide RNAs that negatively regulate the expression of target mRNAs. miRNA-21 is a microRNA that is highly enriched in endothelial cells. miRNA-21 has been shown to be a potential pro-angiogenic factor in some biological systems. Our previous study showed that the expression of miRNA-21 was up-regulated after spinal cord injury. However, the effect of miRNA-21 on angiogenesis in the spinal cord was unclear. In this study, to understand the role of miRNA-21 on injured endothelial cells exclusively, an oxygen and glucose deprivation model of endothelial cells was constructed, and the up-regulation of miRNA-21 was discovered in this model. An increased level of miRNA-21 by mimics promoted the survival, migration and tube formation of endothelial cells, which simultaneously inhibited tissue inhibitor of metalloproteinase-3 (TIMP3) expression and promoted matrix metalloproteinase-2 (MMP2) and matrix metalloproteinase-9 (MMP9) expression and secretion. A decreased level of miRNA-21 by antagomir exerted an opposite effect. As is well known, survival, migration and tube formation of endothelial cells are necessary prerequisites for angiogenesis after injury. TIMP3 was validated as a direct target of miRNA-21 by dual-luciferase reporter assay. Silencing with small interfering RNA against TIMP3 promoted tube formation and increased MMP2 and MMP9 expression at the protein level. In vivo, we found that decreased levels of miRNA-21 inhibited angiogenesis after spinal cord injury in rats using synchrotron radiation micro-computed tomography. In summary, these findings suggest that miRNA-21 has a protective effect on angiogenesis by reducing cell death and promoting cell survival, migration and tube formation via partially targeting the TIMP3 by potentially regulating MMP2 and MMP9. TIMP3 is a functional target gene. Identifying the role of miRNA-21 in the protection of angiogenesis might offer a novel therapeutic target for secondary spinal cord injury, in which angiogenesis is indispensable.
authors.affiliation: Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha, 410008, PR China.
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Hu
authors.affiliation: Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha, 410008, PR China.
authors.forename: Shuangfei
authors.initials: S
authors.lastname: Ni
authors.affiliation: Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha, 410008, PR China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha, 410008, PR China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha, 410008, PR China.
authors.forename: Tianding
authors.initials: T
authors.lastname: Wu
authors.affiliation: Center for Drug Delivery System, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, PR China.
authors.forename: Xianzhen
authors.initials: X
authors.lastname: Yin
authors.affiliation: Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha, 410008, PR China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Lang
authors.affiliation: Department of Sports Medicine, Research Centre of Sports Medicine, Xiangya Hospital, Central South University, Changsha, 410008, PR China.
authors.forename: Hongbin
authors.initials: H
authors.lastname: Lu
mesh_terms: D000818:Animals; D016923:Cell Death; D002465:Cell Movement; D002470:Cell Survival; D005786:Gene Expression Regulation; D061307:Human Umbilical Vein Endothelial Cells; D020778:Matrix Metalloproteinase 2 / Q000235:genetics* / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000235:genetics* / Q000378:metabolism; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D018919:Neovascularization, Physiologic; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D051381:Rats; D019717:Tissue Inhibitor of Metalloproteinase-3 / Q000235:genetics* / Q000378:metabolism
chemical_list: C524940:MIRN21 microRNA, human; D035683:MicroRNAs; D034741:RNA, Small Interfering; D019717:Tissue Inhibitor of Metalloproteinase-3; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9