title: MicroRNA-129-5p modulates epithelial-to-mesenchymal transition by targeting SIP1 and SOX4 during peritoneal dialysis.
abstract: Peritoneal dialysis (PD) is the most readily feasible home-dialysis method for renal replacement therapy. However, repeated use of PD can lead to induction of mesothelial/epithelial-mesenchymal transition (MMT/EMT) and fibrosis, eventually leading to ultrafiltration failure and discontinuation of PD. MicroRNA-129-5p (miR-129-5p) is believed to be a potent downstream inhibitor of TGF-β1 in renal fibrosis, but the effect of miR-129-5p on MMT/EMT relevant to PD is unknown. In this study, as determined by microRNA array analysis and confirmed by northern blot analysis and real-time PCR, we demonstrate that miRNA-129-5p is decreased in mesothelial cells isolated from effluent of patients having PD for more than 6 months extending to several years compared with those who have undergone PD for less than 6 months. The decreased expression of miR-129-5p was accompanied with alterations in EMT-related genes and the expression of respective proteins in vivo. In addition, in in vitro studies we noted that the expression of E-cadherin and claudin-1 were significantly reduced with increased cell migration in HMrSV5, a human peritoneal mesothelial cell line (HPMC), treated with TGF-β1, whereas expression of vimentin, fibronectin and transcription factors SIP1 and SOX4 increased significantly, as assessed by real-time PCR, western blot analysis and immunofluorescence microscopy. Furthermore, alteration in EMT-related genes and proteins were reversed by overexpression of miR-129-5p. No effect was observed in cells treated with miR-negative control. Meanwhile, inhibition of SIP1 and SOX4 with their respective siRNA also could decrease the expression of EMT-related genes and protein levels in HPMCs induced with TGF-β1. Finally, we demonstrate that SIP1 can inhibit the promoter activity of E-cadherin while enhancing the promoter activity of vimentin. We also observed that miR-129-5p could directly target the 3'UTR of SIP1 and SOX4 genes, and repressed their post-transcriptional activities. These data suggest that there is a novel TGF-β1/miR-129-5p/SIP-1 or SOX4 pathway that has a significant role in MMT and fibrosis in the setting of PD.
authors.affiliation: Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
authors.forename: Li
authors.initials: L
authors.lastname: Xiao
authors.affiliation: Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
authors.forename: Xun
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
authors.forename: Fuyou
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
authors.forename: Chun
authors.initials: C
authors.lastname: Hu
authors.affiliation: Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
authors.forename: Xuejing
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
authors.forename: Xiaoxuan
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
authors.forename: Shikun
authors.initials: S
authors.lastname: Yang
authors.affiliation: Departments of Pathology and Medicine, Northwestern University, Chicago, IL, USA.
authors.forename: Yashpal S
authors.initials: YS
authors.lastname: Kanwar
authors.affiliation: Department of Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Sun
mesh_terms: D020413:3' Untranslated Regions; D015820:Cadherins / Q000378:metabolism; D002460:Cell Line; D058750:Epithelial-Mesenchymal Transition; D005260:Female; D005786:Gene Expression Regulation; D018398:Homeodomain Proteins / Q000378:metabolism*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000378:metabolism / Q000628:therapy; D008297:Male; D035683:MicroRNAs / Q000378:metabolism*; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000009:adverse effects*; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000378:metabolism*; D055751:SOXC Transcription Factors / Q000378:metabolism*; D053773:Transforming Growth Factor beta1; D014746:Vimentin / Q000378:metabolism; D000074165:Zinc Finger E-box Binding Homeobox 2
chemical_list: D020413:3' Untranslated Regions; D015820:Cadherins; D018398:Homeodomain Proteins; D035683:MicroRNAs; C541915:Mirn129 microRNA, human; D012097:Repressor Proteins; C083431:SOX4 protein, human; D055751:SOXC Transcription Factors; D053773:Transforming Growth Factor beta1; D014746:Vimentin; C492363:ZEB2 protein, human; D000074165:Zinc Finger E-box Binding Homeobox 2