Differentially expressed microRNAs in bone marrow mesenchymal stem cell-derived microvesicles in young and older rats and their effect on tumor growth factor-β1-mediated epithelial-mesenchymal transition in HK2 cells

Abstract

IntroductionThe prevalence of renal fibrosis is higher in older than in younger individuals. Through paracrine activity, bone marrow mesenchymal stem cell-derived microvesicles (BM-MSC-MVs) influence the process of renal fibrosis. Differences in microRNA (miRNA) expression of BM-MSC-MVs that correlate with the age of the subjects and the correlation between miRNA expression and the process of renal fibrosis have not been established. The present study aimed to analyze differences in miRNA expression of BM-MSC-MVs between young or older rats and its influence on tumor growth factor-beta 1 (TGF-β1)-mediated epithelial-mesenchymal transition (EMT) of HK2 cells to explore the causes of renal fibrosis in aged tissues.MethodsmiRCURY LNA Array (version 18.0) was used to identify differentially expressed miRNAs in BM-MSC-MVs of 3- and 24-month-old Fisher344 rats. Reverse transcription-polymerase chain reaction was used to verify miRNA levels in BM-MSC-MVs and in the serum of rats. A TGF-β1-mediated EMT model was used to study the effects of BM-MSC-MVs and differentially expressed miRNAs on EMT.ResultsBM-MSCs from older rats showed more severe aging phenotypes compared with those of young rats. In addition, the growth rate and cell migration of BM-MSCs derived from older rats were significantly reduced. In secreted BM-MSC-MVs, the expression of miR-344a, miR-133b-3p, miR-294, miR-423-3p, and miR-872-3p was significantly downregulated in older rats than in younger rats (P < 0.05), and the serum level of these miRNAs exhibited the same patterns. Intervention using BM-MSC-MVs resulted in the weakening of TGF-β1-mediated EMT in the aged rats. MiR-344a, miR-133b-3p, and miR-294 affected TGF-β1-mediated EMT in HK2 cells. Among these, miR-133b-3p and miR-294 significantly inhibited TGF-β1-mediated EMT in HK2 cells (P < 0.05).ConclusionsIn older rats, the inhibitory effect of BM-MSC-MVs on TGF-β1-mediated HK2 cell EMT was weaker than that observed in younger rats. In addition, miR-133b-3p and miR-294, which were downregulated in BM-MSC-MVs of older rats, remarkably inhibited TGF-β1-mediated EMT in HK2 cells, suggesting that these may play a role in the fibrosis of aging renal tissues.Electronic supplementary materialThe online version of this article (doi:10.1186/s13287-015-0179-x) contains supplementary material, which is available to authorized users.

Clinical verification of a novel urinary microRNA panal: 133b, -342 and -30 as biomarkers for diabetic nephropathy identified by bioinformatics analysis

“…miR-133b was reported as a kidney tumor suppressor [23] and was dysregulated in polycystic kidney disease [24]. Wang groups found that the miR-133b-3p which was downregulated in bone marrow mesenchymal stem cell-derived microvesicles of older rats, remarkably inhibited TGF-b1-mediated EMT in HK2 cells, suggesting that these may play a role in the fibrosis of aging renal tissues [25]. In addition, Yildirim et al reported that the expression levels of miR-133a, and miR-133b were markedly depressed in the diabetic cardiomyocytes [26].…”

Vesicles bearing gifts: the functional importance of micro-RNA transfer in extracellular vesicles in chronic kidney disease

“…It has been reported that EVs derived from bone marrow mesenchymal stem cells (MSC-EVs) suppress TGF-␤1-induced morphological changes and expression of ␣-smooth muscle actin in cells in vitro, and in vivo injection of MSC-EVs blunted the increase in blood urea nitrogen and serum creatinine in the mouse UUO model (67). In Fisher 344 rats, both the animals' serum and MSC-EVs as above have been shown to contain miR-344a, miR-133b-3p, miR-294, miR-423-3p, and miR-872-3p, and this miR expression declined significantly as the rats aged (150). In the same study miR-133b-3p and miR-294 strongly suppressed TGF-␤1-mediated EMT in HK2 cells in vitro, leading the authors to suggest that age-dependent decline in these miRs within stem cell-derived EVs partly mediates the well-documented increase in renal fibrosis that occurs with aging.…”

Mesenchymal Stem Cell Derived Extracellular Vesicles in Aging

“…A panel of inflammamiRs commonly identified in distinct cell types includes miR-19b, miR-20a, miR-21, miR-126, miR-146a, and miR-155. In MSC-EVs, expression of several miRNAs is modulated with increasing age (for review, see Fafian-Labora et al, 2017). A decreased expression of a number of miRNAs was observed in MSC-EVs from old versus young rats (Wang et al, 2015). A significant decrease was confirmed for miR-294 and miR-872-3p.…”