The MicroRNA miR-199a-5p Down-regulation Switches on Wound Angiogenesis by Derepressing the v-ets Erythroblastosis Virus E26 Oncogene Homolog 1-Matrix Metalloproteinase-1 Pathway

• Published in: The Journal of biological chemistry 2012-11, Vol.287 (49), p.41032-41043
• Main Authors: Chan, Yuk Cheung, Roy, Sashwati, Huang, Yue, Khanna, Savita, Sen, Chandan K.
• Format: Article
• Language: English
• Subjects: Angiogenesis; Animals; Cell Line; Cell Movement; Down-Regulation; Endothelial Cell; Endothelial Cells - cytology; Ets Family Transcription Factor; Gene Expression Regulation, Enzymologic; Humans; Male; Matrix Metalloproteinase (MMP); Matrix Metalloproteinase 1 - metabolism; Mice; Mice, Inbred C57BL; Microcirculation; MicroRNA; MicroRNAs - metabolism; miR-199a-5p; Models, Biological; Neovascularization, Physiologic; Proto-Oncogene Protein c-ets-1 - metabolism; Proto-Oncogene Protein c-ets-1 - physiology; Signal Transduction; Skin - pathology; Wound Healing
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M112.413294

miR-199a-5p plays a critical role in controlling cardiomyocyte survival. However, its significance in endothelial cell biology remains ambiguous. Here, we report the first evidence that miR-199a-5p negatively regulates angiogenic responses by directly targeting v-ets erythroblastosis virus E26 oncogene homolog 1 (Ets-1). Induction of miR-199a-5p in human dermal microvascular endothelial cells (HMECs) blocked angiogenic response in Matrigel® culture, whereas miR-199a-5p-deprived cells exhibited enhanced angiogenesis in vitro. Bioinformatics prediction and miR target reporter assay recognized Ets-1 as a novel direct target of miR-199a-5p. Delivery of miR-199a-5p blocked Ets-1 expression in HMECs, whereas knockdown endogenous miR-199a-5p induced Ets-1 expression. Matrix metalloproteinase 1 (MMP-1), one of the Ets-1 downstream mediators, was negatively regulated by miR-199a-5p. Overexpression of Ets-1 not only rescued miR-199a-5p-dependent anti-angiogenic effects but also reversed miR-199a-5p-induced loss of MMP-1 expression. Similarly, Ets-1 knockdown blunted angiogenic response and induction of MMP-1 in miR-199a-5p-deprived HMECs. Examination of cutaneous wound dermal tissue revealed a significant down-regulation of miR-199a-5p expression, which was associated with induction of Ets-1 and MMP-1. Mice carrying homozygous deletions in the Ets-1 gene exhibited blunted wound blood flow and reduced abundance of endothelial cells. Impaired wound angiogenesis was associated with compromised wound closure, insufficient granulation tissue formation, and blunted induction of MMP-1. Thus, down-regulation of miR-199a-5p is involved in the induction of wound angiogenesis through derepressing of the Ets-1-MMP1 pathway. Background: The role of miR-199a-5p in angiogenesis remains unclear. Results: miR-199a-5p exerts angiostatic effects by targeting Ets-1-MMP1 pathway and is down-regulated in skin wound healing. Conclusion: Down-regulation of miR-199a-5p switches on wound angiogenesis through derepressing of Ets-1-MMP1 pathway. Significance: This investigation provides novel mechanistic insight explaining miR-dependent regulation of wound angiogenesis and the foundation of developing therapeutic intervention in treating chronic nonhealing wounds.