First Author | Wang JY | Year | 2014 |
Journal | Mol Cell Endocrinol | Volume | 392 |
Issue | 1-2 | Pages | 163-72 |
PubMed ID | 24887517 | Mgi Jnum | J:212388 |
Mgi Id | MGI:5581345 | Doi | 10.1016/j.mce.2014.05.018 |
Citation | Wang JY, et al. (2014) miR-21 overexpression enhances TGF-beta1-induced epithelial-to-mesenchymal transition by target smad7 and aggravates renal damage in diabetic nephropathy. Mol Cell Endocrinol 392(1-2):163-72 |
abstractText | Epithelial-to-mesenchymal transition (EMT) plays an important role in renal interstitial fibrosis (RIF) with diabetic nephropathy (DN). Smad7 (a inhibitory smad), a downstream signaling molecules of TGF-beta1, represses the EMT. The physiological function of miR-21 is closely linked to EMT and RIF. However, it remained unclear whether miR-21 over-expression affected TGF-beta1-induced EMT by regulating smad7 in DN. In this study, real-time RT-PCR, cell transfection, luciferase reporter gene assays, western blot and confocal microscope were used, respectively. Here, we found that miR-21 expression was upregulated by TGF-beta1 in time- and concentration -dependent manner. Moreover, miR-21 over-expression enhanced TGF-beta1-induced EMT(upregulation of a-SMA and downregulation of E-cadherin) by directly down-regulating smad7/p-smad7 and indirectly up-regulating smad3/p-smad3, accompanied by the decrease of Ccr and the increase of col-IV, FN, the content of collagen fibers, RTBM, RTIAW and ACR. Meantime, the siRNA experiment showed that smad7 can directly regulate a-SMA and E-cadherin expression. More importantly, miR-21 inhibitor can not only inhibit EMT and fibrosis but also ameliorate renal structure and function. In conclusion, our results demonstrated that miR-21 overexpression can contribute to TGF-beta1-induced EMT by inhibiting target smad7, and that targeting miR-21 may be a better alternative to directly suppress TGF-beta1-mediated fibrosis in DN. |