CircRNA Arf3 suppresses glomerular mesangial cell proliferation and fibrosis in diabetic nephropathy via miR-107-3p/Tmbim6 axis.

Diabetic nephropathy (DN) is one of microvascular complication associated with diabetes. Circular RNAs (circRNAs) have been shown to be involved in DN pathogenesis. Hence, this work aimed to explore the role and mechanism of circ_Arf3 in DN. Mouse mesangial cells (MCs) cultured in high glucose (HG) condition were used for functional analysis. Cell proliferation was determined using 5-ethynyl-2'-deoxyuridine (EdU) and cell counting kit-8 assays. Western blotting was used to measure the levels of proliferation indicator PCNA and fibrosis-related proteins α-smooth muscle actin (α-SMA), collagen I (Col I), fibronectin (FN), and collagen IV (Col IV). The binding interaction between miR-107-3p and circ_Arf3 or Tmbim6 (transmembrane BAX inhibitor motif containing 6) was confirmed using dual-luciferase reporter and pull-down assays. Circ_Arf3 is a stable circRNA, and the expression of circ_Arf3 was decreased after HG treatment in MCs. Functionally, ectopic overexpression of circ_Arf3 protected against HG-induced proliferation and elevation of fibrosis-related proteins in MCs. Mechanistically, circ_Arf3 directly bound to miR-107-3p, and Tmbim6 was a target of miR-107-3p. Further rescue assay showed miR-107-3p reversed the protective action of circ_Arf3 on MCs function under HG condition. Moreover, inhibition of miR-107-3p suppressed HG-induced proliferation and fibrosis, which were attenuated by Tmbim6 knockdown in MCs. CircRNA Arf3 could suppress HG-evoked mesangial cell proliferation and fibrosis via miR-107-3p/Tmbim6 axis, indicating the potential involvement of this axis in DN progression.

Silencing circ_0080425 alleviates high-glucose-induced endothelial cell dysfunction in diabetic nephropathy by targeting miR-140-3p/FN1 axis.

BACKGROUND: Hsa_circ_0080425 (circ_0080425) is newly identified to correlate with the progression of diabetic nephropathy (DN). However, its role and mechanism in DN process is not very clear. METHODS: Cell counting kit-8 assay, flow cytometry, scratch wound assay, and western blotting were performed to measure endothelial cell dysfunction. Expression of circ_0080425, microRNA (miR)-140-3p and fibronectin 1 (FN1) were determined by quantitative real-time PCR and western blotting. The direct interaction was confirmed by dual-luciferase reporter assay. RESULTS: High-glucose (HG) treatment could induce inhibition of cell proliferation, cell cycle entrance and wound healing rate in human umbilical vein endothelial cells (HRGEC), and enhancement of apoptosis rate. Circ_0080425 expression was upregulated by HG, and exhausting circ_0080425 could attenuate HG-induced above effects in HRGEC. MiR-140-3p was sponged by circ_0080425, and its inhibitor reversed the regulation of circ_0080425 knockdown on HG-induced HRGEC injury. FN1 was targeted by miR-140-3p, and its overexpression also restored the inhibitory effect of miR-140-3p on HC-induced HRGEC injury. CONCLUSION: Circ_0080425 expression might contribute to HG-induced endothelial cell injury, and circ_0080425/miR-140-3p/FN1 axis was a potential therapeutic approach to interfere DN process.

Arctigenin alleviates TGF-ß1-induced epithelial-mesenchymal transition and PAI-1 expression via AMPK/NF-κB pathway in peritoneal mesothelial cells.

Peritoneal fibrosis (PF) caused by long-term peritoneal dialysis is closely associated with the epithelial-mesenchymal transition (EMT) of human peritoneal mesothelial cells (HPMCs). Moreover, the anti-fibrotic role of Arctigenin (Arc) has been reported in several fibrosis disorders. Therefore, the preventive effect of Arc on transforming growth factor-ß1 (TGF-ß1)-induced EMT and the underlying mechanisms in HPMCs was investigated in this study. Firstly, the PD model was established by TGF-ß1 stimulation in cultured HPMCs in vitro, we found that TGF-ß1 significantly increased the EMT markers (α-SMA, vimentin, and fibronectin) and plasminogen activator inhibitor type 1 (PAI-1) expressions, but decreased epithelial marker (E-cadherin). Co-treatment with Arc (10, 20, 40 µM) ameliorated TGF-ß1-induced EMT in a dose-dependent manner, and the expression of PAI-1 was also inhibited by Arc, which was abrogated by restoration of PAI-1. Moreover, Arc enhanced the phosphorylated AMP-activated protein kinase (AMPK), but inhibited the phosphorylated IκBα level and nuclear translocation of nuclear factor κB (NF-κB) p65 in TGF-ß1-induced HPMCs. ChIP and Luciferase reporter assays verified that the increased binding capacity of NF-κB to the promoter of PAI-1 induced by TGF-ß1 was reversely attenuated by Arc in HPMCs. However, the effect of Arc on TGF-ß1-induced NF-κB activation, PAI-1 expression and EMT in HPMCs was attenuated by AMPK agonist Compound C. In conclusion, these data demonstrated that Arc suppressed TGF-ß1-induced EMT by activating the AMPK/NF-κB pathway to inhibit PAI-1 expression in HPMCs. Therefore, Arc might act as a potential therapeutic agent for PD treatment.

A Novel Circ_Arf3/miR-452-5p/Mbnl1 Axis Regulates Proliferation and Expression of Fibrosis-Related Proteins of Mouse Mesangial Cells Under High Glucose.

Background: Diabetic nephropathy (DN) is a serious microvascular complication of diabetes that may lead to chronic renal failure and end-stage renal disease. Circular RNAs (circRNAs) play important roles in DN progression. However, the action of circRNA ADP ribosylation factor 3 (circ_Arf3) in high glucose (HG)-induced change is still unclear. Methods: Mouse mesangial cells (MCs) were treated with 30 mM HG as a DN cell model in vitro. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to examine the expression levels of circ_Arf3, microRNA (miR)-452-5p and muscleblind like splicing regulator 1 (Mbnl1). The proliferation of HG-treated MCs was assessed using 5 Ethynyl 2' deoxyuridine (EdU) and cell counting kit-8 (CCK-8) assays, and the levels of proliferation and fibrosis-related proteins and Mbnl1 were detected by Western blot. Dual-luciferase reporter and RNA pull-down assays were utilized to determine the relationship between miR-452-5p and circ_Arf3 or Mbnl1. Results: Our results discovered that circ_Arf3 and Mbnl1 were lowly expressed in HG-treated MCs, while miR-452-5p expression was up-regulated. Moreover, circ_Arf3 was mainly located in the cytoplasm and had a ring-like stable structure. Functional assays demonstrated that overexpression of circ_Arf3 prevented cell proliferation and fibrous formation in HG-treated MCs. Circ_Arf3 could sponge miR-452-5p, and the effect of circ_Arf3 overexpression was reversed by enhanced expression of miR-452-5p. Mbnl1 was a direct target of miR-452-5p. Knockdown of Mbnl1 abolished the suppressive effects of miR-452-5p inhibitor on proliferation and fibrosis-related protein expression in HG-treated MCs. Moreover, circ_Arf3 regulated Mbnl1 through miR-452-5p. Conclusion: Overexpression of circ_Arf3 prevents cell proliferation and fibrous formation in HG-treated MCs by regulating the expression of Mbnl1 via miR-452-5p.

Circular ribonucleic acid nucleoporin 98 knockdown alleviates high glucose-induced proliferation, fibrosis, inflammation and oxidative stress in human glomerular mesangial cells by regulating the microribonucleic acid-151-3p-high mobility group AT-hook 2 axis.

AIMS/INTRODUCTION: This study aimed to investigate the role and mechanism of circular ribonucleic acid nucleoporin 98 (circNUP98) in diabetic nephropathy (DN). MATERIALS AND METHODS: Human glomerular mesangial cells (HMCs) were stimulated with high glucose (HG) to imitate the growth environment of cells under the DN condition. Levels of genes and proteins were tested by quantitative reverse transcription polymerase chain reaction and western blot. Cell proliferation, apoptosis and inflammatory response were analyzed by using cell counting kit-8, flow cytometry and enzyme-linked immunosorbent assay analysis, respectively. Oxidative stress and fibrosis were evaluated by detecting the activity of reactive oxygen species, malondialdehyde, superoxide dismutase, fibronectin and collagen IV. The binding interaction between microribonucleic acid (miR)-151-3p and high mobility group AT-hook 2 (HMGA2) or circNUP98 was confirmed using dual-luciferase reporter, pull-down and ribonucleic acid immunoprecipitation assays. Exosomes were isolated by ultracentrifugation, and qualified by transmission electron microscopy, nanoparticle tracking analysis and western blot. RESULTS: CircNUP98 expression was higher in the serum of DN patients and HG-stimulated HMCs. Functionally, circNUP98 knockdown alleviated HG-induced proliferation, fibrosis, inflammatory response and oxidative stress in HMCs. Mechanistically, circNUP98 directly sponged miR-151-3p, which targeted HMGA2. Rescue experiments showed that miR-151-3p reversed the inhibitory effects of circNUP98 knockdown on HG-induced HMC dysfunction. Furthermore, miR-151-3p re-expression also led to an inhibition of the aforementioned biological behaviors, which was attenuated by HMGA2 upregulation. Besides that, CircNUP98 was found to be packaged into exosomes of DN, and exosomal circNUP98 possessed diagnostic value for DN patients. CONCLUSION: CircNUP98 knockdown alleviates HG-induced proliferation, fibrosis inflammation and oxidative stress in HMCs by regulating the miR-151-3p-HMGA2 axis, which might provide a potential approach for DN therapeutics.

Long noncoding RNA MIAT inhibits the progression of diabetic nephropathy and the activation of NF-κB pathway in high glucose-treated renal tubular epithelial cells by the miR-182-5p/GPRC5A axis.

BACKGROUND: Diabetic nephropathy (DN) is a common diabetic complication. Long noncoding RNAs (lncRNAs) have been identified as essential regulators in DN progression. This study is devoted to the research of lncRNA-myocardial infarction-associated transcript (MIAT) in DN. METHODS: DN cell model was established by high glucose (HG) treatment for human renal tubular epithelial cells (HK-2). Cell viability and colonizing capacity were analyzed by Cell Counting Kit-8 (CCK-8) and colony formation assay. Apoptosis was assessed via caspase-3 detection and flow cytometry. Enzyme-linked immunosorbent assay (ELISA) was used for evaluating inflammation. The protein determination was completed using western blot. MIAT, microRNA-182-5p (miR-182-5p), and G protein-coupled receptor class C group 5 member A (GPRC5A) levels were all examined via reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Intergenic binding was verified using dual-luciferase reporter, RNA immunoprecipitation (RIP), and RNA pull-down assays. RESULTS: HG induced the inhibition of cell growth, but accelerated apoptosis and inflammation as well as the activation of nuclear factor kappa B (NF-κB) pathway. MIAT reestablishment prevented the HG-induced cell damages and NF-κB signal activation. Mechanistically, MIAT was proved as a miR-182-5p sponge and regulated the expression of GPRC5A that was a miR-182-5p target. The rescued experiments demonstrated that MIAT downregulation or miR-182-5p upregulation aggravated the HG-induced cell damages and activated the NF-κB pathway via the respective regulation of miR-182-5p or GPRC5A. CONCLUSION: Taken together, MIAT functioned as an inhibitory factor in the pathogenesis to impede the development of DN and inactivate the NF-κB pathway via regulating the miR-182-5p/GPRC5A axis.

Effects of an Omaha system-based continuing nursing program on nutritional status in patients undergoing peritoneal dialysis: a randomized controlled trial.

PURPOSE: This study was aimed to develop and conduct an Omaha system-based continuing nursing program for chronic kidney disease (CKD) patients undergoing peritoneal dialysis (PD) and to explore its effect on patients' nutritional status. METHODS: A randomized controlled trial was performed in a teaching hospital in China between June 2017 and July 2018. A total of 203 eligible patients were included and then randomly assigned to the study group (n = 101) or the control group (n = 102). In the study group, health education, treatments and procedures, case management, and surveillance based on the Omaha system were used. In the control group, only common outpatient nursing intervention was given to the patients. Changes in subjective global assessment (SGA), anthropometric measurements including body mass index (BMI), triceps skin-fold thickness (TSF), mid-arm muscle circumference (MAMC), and handgrip strength (HGS), and biochemical parameters (hemoglobin, albumin, pre-albumin, total cholesterol, and creatinine) were evaluated before the intervention and 6 months after the intervention and differences in measurements were analyzed. RESULTS: After intervention, the proportion of well-nourished patients in the study group was significantly improved from 6.19 to 29.90% ([Formula: see text]2 = 18.441, P < 0.001), and after 6 months, this was higher in the study group than that in the control group (29.90% vs 9.28%, [Formula: see text]2 = 13.090, P < 0.001). Also, mean TSF, MAMC, and HGS were significantly improved in the study group and after 6 months, these levels were higher in the study group than those in the control group (P < 0.05). In addition, levels of hemoglobin, albumin, and pre-albumin in patients in the study group were significantly increased and after 6 months, these levels were higher in the study group than those in the control group (P < 0.05). CONCLUSIONS: The continuing nursing program based on the Omaha system improved patients' nutritional status and should be further examined in future studies.