scholarly journals Silencing of long noncoding RNA XIST protects against renal interstitial fibrosis in diabetic nephropathy via microRNA-93-5p-mediated inhibition of CDKN1A

2019 ◽  
Vol 317 (5) ◽  
pp. F1350-F1358 ◽  
Author(s):  
Jindou Yang ◽  
Yan Shen ◽  
Xia Yang ◽  
Yanjun Long ◽  
Shuang Chen ◽  
...  

Long noncoding RNAs (lncRNAs) have been reported to play an important role in diabetic nephropathy (DN). However, the molecular mechanism involved in this process remains poorly understood. Thus, the present study aimed to explore the function and molecular mechanism of dysregulated lncRNA X-inactive specific transcript (XIST) in DN. DN mouse models were established by streptozotocin treatment, and human renal tubular epithelial HK-2 cells were exposed to high glucose to produce an in vitro model. XIST was highly expressed in renal tissues of patients with DN, mice with DN, and high glucose-exposed HK-2 cells. To identify the interaction among XIST, miR-93-5p, and cyclin-dependent kinase inhibitor 1A (CDKN1A) and to analyze the functional significance of their interaction in renal interstitial fibrosis, we altered endogenous expression of XIST and miR-93-5p and CDKN1A. Dual-luciferase reporter assay results suggested that XIST was highly expressed in the kidney tissue of DN mice and high glucose-exposed HK-2 cells. XIST was identified to be a lncRNA that could bind to miR-93-5p, and CDKN1A was a target of miR-93-5p. Downregulated expression of XIST led to an increase in miR-93-5p expression, thereby decreasing CDKN1A and suppressing renal interstitial fibrosis in DN. Consistently, XIST knockdown reduced the expression of fibrosis markers (fibronectin, collagen type IV, and transforming growth factor-β1). Restoration of CDKN1A or decreasing miR-93-5p yielded a reversed effect on renal interstitial fibrosis. In conclusion, our study demonstrated that silenced XIST inducing miR-93-5p-dependent CDKN1A inhibition was beneficial for preventing renal interstitial fibrosis in DN, which may provide a future strategy to prevent the progression of DN.

Author(s):  
Liming Guo ◽  
Kuibi Tan ◽  
Qun Luo ◽  
Xu Bai

Diabetic nephropathy (DN) is the most common complication of diabetes and is prone to kidney failure. Dihydromyricetin (DHM) has been reported to have a variety of pharmacological activities. This study aims to explore the effect of DHM on DN and the underlying molecular mechanism. An in vivo DN rat model was established. The degree of renal interstitial fibrosis (RIF) was detected by hematoxylin-eosin (HE) staining, Masson's trichrome staining, and immunohistochemistry (IHC). In vitro, NRK-52E cells were divided into four groups: normal glucose (NG), high glucose (HG), HG+DHM, and HG+rapamycin (autophagy inhibitor). The levels of autophagy- and fibrosis-related proteins were analyzed by western blotting. The expression of miR-155-5p and phosphatase and tensin homolog deleted on chromosome ten (PTEN) and their relationship were assessed by quantitative reverse transcription (qRT)-PCR and dual luciferase reporter gene assay. Our results showed that RIF was increased in DN rat model and in HG-induced NRK-52E cells. DHM treatment attenuated the increased RIF and also increased autophagy. MiR-155-5p expression was increased, while PTEN expression was decreased in DN rat and cell model, and DHM reversed both effects. Dual luciferase assay showed that PTEN was the target gene of miR-155-5p. DHM inhibited HG-induced fibrosis and promoted autophagy by inhibiting miR-155-5p expression in NRK-52E cells. In addition, DHM promoted autophagy by inhibiting the PI3K/AKT/mTOR signaling pathway. In conclusion, DHM promotes autophagy and attenuates RIF by regulating the miR-155-5p/PTEN signaling and PI3K/AKT/mTOR signaling pathway in DN.


2020 ◽  
pp. 096032712095215
Author(s):  
H-J Wang ◽  
H Liu ◽  
Y-H Lin ◽  
S-J Zhang

Diabetic nephropathy (DN) is primary cause of end-stage renal disease. A previous study has shown that miR-32-5p (miR-32) is highly expressed in kidney tissue during chronic allograft dysfunction with interstitial fibrosis and tubular atrophy. However, the role of miR-32-5p (miR-32) in DN is still unclear. In this study, streptozotocin-induced DN rat models and high glucose (HG)-incubated human kidney proximal tubular epithelial (HK-2) cells were established to investigate the role and underlying mechanisms of miR-32 in DN. Results of real-time PCR revealed that miR-32 levels were greatly increased in DN rats and HG-incubated HK-2 cells. Downregulation of miR-32 effectively relieved HG-induced autophagy suppression, fibrosis, epithelial-mesenchymal transition (EMT) and inflammation in HK-2 cells. Besides, miR-32 overexpression significantly down-regulated the expression of mothers against decapentaplegic homolog 7 (SMAD7), whereas knockdown of miR-32 markedly up-regulated the level of SMAD7. Dual-luciferase reporter gene assay confirmed that SMAD7 was a target of miR-32. Reintroduction of SMAD7 expression rescued miR-32-induced HK-2 cells autophagy suppression, EMT and renal fibrosis. Our findings indicate that miR-32 may play roles in the progression of EMT and fibrosis in DN.


2015 ◽  
Vol 309 (6) ◽  
pp. F559-F568 ◽  
Author(s):  
Vanessa Marchant ◽  
Alejandra Droguett ◽  
Graciela Valderrama ◽  
M. Eugenia Burgos ◽  
Daniel Carpio ◽  
...  

Diabetic nephropathy (DN) is currently a leading cause of end-stage renal failure worldwide. Gremlin was identified as a gene differentially expressed in mesangial cells exposed to high glucose and in experimental diabetic kidneys. We have described that Gremlin is highly expressed in biopsies from patients with diabetic nephropathy, predominantly in areas of tubulointerstitial fibrosis. In streptozotocin (STZ)-induced experimental diabetes, Gremlin deletion using Grem1 heterozygous knockout mice or by gene silencing, ameliorates renal damage. To study the in vivo role of Gremlin in renal damage, we developed a diabetic model induced by STZ in transgenic (TG) mice expressing human Gremlin in proximal tubular epithelial cells. The albuminuria/creatinuria ratio, determined at week 20 after treatment, was significantly increased in diabetic mice but with no significant differences between transgenic (TG/STZ) and wild-type mice (WT/STZ). To assess the level of renal damage, kidney tissue was analyzed by light microscopy (periodic acid-Schiff and Masson staining), electron microscopy, and quantitative PCR. TG/STZ mice had significantly greater thickening of the glomerular basement membrane, increased mesangial matrix, and podocytopenia vs. WT/STZ. At the tubulointerstitial level, TG/STZ showed increased cell infiltration and mild interstitial fibrosis. In addition, we observed a decreased expression of podocin and overexpression of monocyte chemoattractant protein-1 and fibrotic-related markers, including transforming growth factor-β1, Col1a1, and α-smooth muscle actin. Together, these results show that TG mice overexpressing Gremlin in renal tubules develop greater glomerular and tubulointerstitial injury in response to diabetic-mediated damage and support the involvement of Gremlin in diabetic nephropathy.


Pharmacology ◽  
2022 ◽  
pp. 1-10
Author(s):  
Huihui Hu ◽  
Caipeng Xie ◽  
Zeping Weng ◽  
Pei Yu ◽  
Yuqiang Wang ◽  
...  

<b><i>Introduction:</i></b> Doxorubicin (DOX), an anthracycline antitumor agent, has been widely used against various solid tumors and hematological malignancies. However, the clinical application of DOX is restricted by its multiple organ toxicity including nephrotoxicity. This study investigated the protective effects and mechanisms of dexrazoxane (DZR) against DOX-induced nephropathy in rats. <b><i>Methods:</i></b> Male Sprague Dawley rats received 2.5 mg/kg DOX once a week for 5 consecutive weeks. 24-h urinary protein and renal function injury biomarkers were determined to evaluate the renal function. Histopathological changes and glomerulosclerosis were examined by hematoxylin and eosin and periodic acid-Schiff staining. The change of renal ultrastructure in the DOX-induced rats was observed by the electron microscopy. The renal apoptosis was detected by TUNEL staining and measured the protein expression of Caspase-3, Bcl-2, and Bax. Renal interstitial fibrosis was determined by Masson staining and immunohistochemistry examination. The levels of vimentin, alpha-smooth muscle actin (α-SMA), and transforming growth factor β (TGF-β) in kidney tissue were detected by Western blot. <b><i>Results:</i></b> DZR pretreatment markedly raised the survival rate and improved the renal dysfunction in DOX-treated rats. DZR ameliorated DOX-induced histopathological lesion of glomerular and tubular and apoptosis. DZR restored the oxidant/antioxidant balance via regulating the levels of MDA, SOD, and TAC. DZR reduced DOX-induced collagen IV deposition and renal interstitial fibrosis and downregulated the fibrosis-related protein expressions of vimentin, α-SMA, and TGF-β1. <b><i>Conclusion:</i></b> Our results suggest DZR exerted its protective effects against DOX-induced nephropathy through inhibition of lipid peroxidation, apoptosis, and fibrosis.


Author(s):  
Haiyun Sun ◽  
Chong Wang ◽  
Ying Zhou ◽  
Xingbo Cheng

Objective: Diabetic cardiomyopathy (DCM) is an important complication of diabetes. This study was attempted to discover the effects of long noncoding RNA OIP5-AS1 (OIP5-AS1) on the viability and oxidative stress of cardiomyocyte in DCM. Methods: The expression of OIP5-AS1 and microRNA-34a (miR-34a) in DCM was detected by qRT-PCR. In vitro, DCM was simulated by high glucose (HG, 30 mM) treatment in H9c2 cells. The viability of HG (30 mM)-treated H9c2 cells was examined by MTT assay. The reactive oxygen species (ROS), superoxide dismutase (SOD) and malondialdehyde (MDA) levels were used to evaluate the oxidative stress of HG (30 mM)-treated H9c2 cells. Dual-luciferase reporter assay was used to confirm the interactions among OIP5-AS1, miR-34a and SIRT1. Western blot was applied to analyze the protein expression of SIRT1. Results: The expression of OIP5-AS1 was down-regulated in DCM, but miR-34a was up-regulated. The functional experiment stated that OIP5-AS1 overexpression increased the viability and SOD level, while decreased the ROS and MDA levels in HG (30 mM)-treated H9c2 cells. The mechanical experiment confirmed that OIP5-AS1 and SIRT1 were both targeted by miR-34a with the complementary binding sites at 3′UTR. MiR-34a overexpression inhibited the protein expression of SIRT1. In the feedback experiments, miR-34a overexpression or SIRT1 inhibition weakened the promoting effect on viability, and mitigated the reduction effect on oxidative stress caused by OIP5-AS1 overexpression in HG (30 mM)-treated H9c2 cells. Conclusions: OIP5-AS1 overexpression enhanced viability and attenuated oxidative stress of cardiomyocyte via regulating miR-34a/SIRT1 axis in DCM, providing a new therapeutic target for DCM.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Jie Yun ◽  
Jinyu Ren ◽  
Yufei Liu ◽  
Lijuan Dai ◽  
Liqun Song ◽  
...  

Abstract Background Circular RNAs (circRNAs) have been considered as pivotal biomarkers in Diabetic nephropathy (DN). CircRNA ARP2 actin-related protein 2 homolog (circ-ACTR2) could promote the HG-induced cell injury in DN. However, how circ-ACTR2 acts in DN is still unclear. This study aimed to explore the molecular mechanism of circ-ACTR2 in DN progression, intending to provide support for the diagnostic and therapeutic potentials of circ-ACTR2 in DN. Methods RNA expression analysis was conducted by the quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Cell growth was measured via Cell Counting Kit-8 and EdU assays. Inflammatory response was assessed by Enzyme-linked immunosorbent assay. The protein detection was performed via western blot. Oxidative stress was evaluated by the commercial kits. The molecular interaction was affirmed through dual-luciferase reporter and RNA immunoprecipitation assays. Results Circ-ACTR2 level was upregulated in DN samples and high glucose (HG)-treated human renal mesangial cells (HRMCs). Silencing the circ-ACTR2 expression partly abolished the HG-induced cell proliferation, inflammation and extracellular matrix accumulation and oxidative stress in HRMCs. Circ-ACTR2 was confirmed as a sponge for miR-205-5p. Circ-ACTR2 regulated the effects of HG on HRMCs by targeting miR-205-5p. MiR-205-5p directly targeted high-mobility group AT-hook 2 (HMGA2), and HMGA2 downregulation also protected against cell injury in HG-treated HRMCs. HG-mediated cell dysfunction was repressed by miR-205-5p/HMGA2 axis. Moreover, circ-ACTR2 increased the expression of HMGA2 through the sponge effect on miR-205-5p in HG-treated HRMCs. Conclusion All data have manifested that circ-ACTR2 contributed to the HG-induced DN progression in HRMCs by the mediation of miR-205-5p/HMGA2 axis.


Endocrinology ◽  
2021 ◽  
Vol 162 (11) ◽  
Author(s):  
Tsai-Der Chuang ◽  
Derek Quintanilla ◽  
Drake Boos ◽  
Omid Khorram

Abstract The objective of this study was to determine the expression and functional role of a long noncoding RNA (lncRNA) MIAT (myocardial infarction–associated transcript) in leiomyoma pathogenesis. Leiomyoma compared with myometrium (n = 66) expressed significantly more MIAT that was independent of race/ethnicity and menstrual cycle phase but dependent on MED12 (mediator complex subunit 12) mutation status. Leiomyomas bearing the MED12 mutation expressed higher levels of MIAT and lower levels of microRNA 29 family (miR-29a, -b, and -c) compared with MED12 wild-type leiomyomas. Using luciferase reporter activity and RNA immunoprecipitation analysis, MIAT was shown to sponge the miR-29 family. In a 3-dimensional spheroid culture system, transient transfection of MIAT siRNA in leiomyoma smooth muscle cell (LSMC) spheroids resulted in upregulation of miR-29 family and downregulation of miR-29 targets, collagen type I (COL1A1), collagen type III (COL3A1), and TGF-β3 (transforming growth factor β-3). Treatment of LSMC spheroids with TGF-β3 induced COL1A1, COL3A1, and MIAT levels, but repressed miR-29 family expression. Knockdown of MIAT in LSMC spheroids blocked the effects of TGF-β3 on the induction of COL1A1 and COL3A1 expression. Collectively, these results underscore the physiological significance of MIAT in extracellular matrix accumulation in leiomyoma.


2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Guo Guang Wang ◽  
Xiao Hua Lu ◽  
Wei Li ◽  
Xue Zhao ◽  
Cui Zhang

Diabetic nephropathy is a long-term complication of diabetic mellitus. Many experimental evidences suggest that persistent hyperglycaemia generates intracellular reactive oxygen species (ROS) and upregulates transforming growth factor-b1 and extracellular matrix expression in mesangial and tubular epithelial cells, which is involved of free radicals in the pathogenesis of diabetes and more importantly in the development of diabetic complications. Antioxidants effectively inhibit high-glucose- and H2O2-induced transforming growth factor-b1 and fibronectin upregulation, thus providing evidence that ROS play an important role in high glucose-induced renal injury. The flavonoid luteolin has been shown to possess direct antioxidant activity, therefore we hypothesize that it may be useful in treatment of many chronic disease associated with oxidative stress, such as diabetic nephropathy via its antioxidant properties. Our results suggested that protection against development of diabetic nephropathy by luteolin treatment involved changes in superoxide dismutase (SOD) activity, the malondialdehyde (MDA) content and expression of Heme Oxygenase-1 (HO-1) protein.


2007 ◽  
Vol 195 (1) ◽  
pp. 95-103 ◽  
Author(s):  
Nina Renlund ◽  
Francis H O’Neill ◽  
LiHua Zhang ◽  
Yisrael Sidis ◽  
Jose Teixeira

Activin receptor-like kinase-2 (Alk2) has been shown to be a promiscuous type I receptor for the transforming growth factor β (TGFβ) family of growth and differentiation factors, such as activin, bone morphogenetic proteins, and Müllerian inhibiting substance (MIS). We have studied the putative role of Alk2 in activin signaling using MA-10 cells, a mouse transformed Leydig cell line, in which endogenous expression of cytochrome P450 c17 hydroxylase/C17–20 lyase mRNA is inhibited by both MIS and activin A. Overexpression of Alk2 in MA-10 cells inhibited the activation of the activin-responsive CAGA-luciferase reporter and, conversely, transfection of siRNA for Alk2 increased the response. In contrast, overexpression of the MIS type II receptor in MA-10 cells increased the activin-mediated induction of CAGA-luciferase approximately fivefold, which we hypothesized occurs by MIS type II receptor sequestering endogenous Alk2. Binding experiments with 125I-labeled activin show that the underlying mechanism of Alk2-mediated inhibition of activin signaling involves Alk2 blocking the access of activin to its type II receptor, which we show can bind Alk2 in the absence of ligand. These results show that the complement of other type I receptors in addition to the ligand-specific type I receptor can provide an important mechanism for modulating cell-specific responses to members of the TGFβ family.


2019 ◽  
Vol 316 (6) ◽  
pp. F1162-F1172 ◽  
Author(s):  
Qingqing Wei ◽  
Jennifer Su ◽  
Guie Dong ◽  
Ming Zhang ◽  
Yuqing Huo ◽  
...  

Renal interstitial fibrosis is a common pathological feature of chronic kidney disease that may involve changes of metabolism in kidney cells. In the present study, we first showed that blockade of glycolysis with either dichloroacetate (DCA) or shikonin to target different glycolytic enzymes reduced renal fibrosis in a mouse model of unilateral ureteral obstruction (UUO). Both inhibitors evidently suppressed the induction of fibronectin and collagen type I in obstructed kidneys, with DCA also showing inhibitory effects on collagen type IV and α-smooth muscle actin (α-SMA). Histological examination also confirmed less collagen deposition in DCA-treated kidneys. Both DCA and shikonin significantly inhibited renal tubular apoptosis but not interstitial apoptosis in UUO. Macrophage infiltration after UUO injury was also suppressed. Shikonin, but not DCA, caused obvious animal weight loss during UUO. To determine whether shikonin and DCA worked on tubular cells and/or fibroblasts, we tested their effects on cultured renal proximal tubular BUMPT cells and renal NRK-49F fibroblasts during hypoxia or transforming growth factor-β1 treatment. Although both inhibitors reduced fibronectin and α-SMA production in NRK-49F cells during hypoxia or transforming growth factor-β1 treatment, they did not suppress fibronectin and α-SMA expression in BUMPT cells. Altogether, these results demonstrate the inhibitory effect of glycolysis inhibitors on renal interstitial fibrosis. In this regard, DCA is more potent for fibrosis inhibition and less toxic to animals than shikonin.


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