Down-regulation of the long non-coding RNA XIST ameliorates podocyte apoptosis in membranous nephropathy via the miR-217-TLR4 pathway.

NEW FINDINGS: What is the central question of this study? What is the role of the long non-coding RNA X-inactive specific transcript (XIST), which is up-regulated in injured podocytes and membranous nephropathy, in the pathogenesis of membranous nephropathy? What is the main finding and its importance? XIST was up-regulated in kidney tissue with membranous nephropathy and in injured podocytes. Down-regulation of XIST inhibited podocyte apoptosis. XIST negatively regulated miR-217, and miR-217 modulated Toll-like receptor 4. Inhibition of XIST suppressed podocyte apoptosis induced by angiotensin II via miR-217. ABSTRACT: Membranous nephropathy is often characterized by glomerular podocyte injury. Up-regulation of the long non-coding RNA (lncRNA) X-inactive specific transcript (XIST) has been verified in membranous nephropathy and in injured podocytes. Here the role of XIST in podocyte injury and membranous nephropathy was explored. Quantitative real-time PCR and western blot were performed to detect the expression of XIST and miR-217, and Toll-like receptor 4 (TLR4) protein, respectively. Podocyte apoptosis was evaluated with flow cytometry. Interaction between XIST and miR-217 was analysed by RNA immunoprecipitation and RNA pull-down assay. A dual luciferase reporter assay was used to examine the interplay between miR-217 and TLR4. Up-regulation of the lncRNA XIST and angiotensin II (Ang II) and kidney and podocyte injury were indicated in kidney tissue of patients with membranous nephropathy. Increase of XIST and apoptosis were induced by Ang II in podocytes. Down-regulation of XIST reversed podocyte apoptosis induced by Ang II. MiR-217 was negatively regulated by XIST. MiR-217 controlled TLR4 by targeting its 3'-untranslated region. XIST modulated TLR4 through miR-217 and inhibition of XIST reduced podocyte apoptosis induced by Ang II via regulating miR-217. Down-regulation of XIST ameliorates podocyte apoptosis via the miR-217-TLR4 pathway, which may improve membranous nephropathy.

Cytotoxicity and Genotoxicity in Human Embryonic Kidney Cells Exposed to Surface Modify Chitosan Nanoparticles Loaded with Curcumin.

The rapid progress in the development and scientific investments of modified nanoparticles are due to their owed activity to various diseased conditions for which they are prepared. But the toxicity which they cause cannot be overlooked. The present study demonstrates the development of phosphatidylserine (PS)-coated chitosan (CS) nanoparticles (NPs) loaded with curcumin (CU), which was then investigated against human embryonic kidney cells (HEK 293) for its cytotoxic and genotoxic effect in rats. The CU-loaded CNPs (CNPs-CU) have been prepared by ionic gelation method, later which were grafted with PS. CNPs-CU and PS-CNPs-CU have been evaluated for their size, poly dispersity index, amount of drug entrapped, and in vitro CU release. CNPs-CU has an average size 167.6 ± 3.53 nm and polydispersity index (PDI) 0.115 ± 0.014, whereas PS-CNPs-CU shows average size 220 ± 3.67 nm and PDI 0.148 ± 0.019. Surface morphology of prepared NPs was confirmed by high-resolution transmission electron microscopy (HR-TEM). There was no major difference in cell viability between PS-CNPs-CU and CNPs-CU when they were exposed to HEK 293 cells at all equivalent concentrations. A series of genotoxic studies were conducted, which revealed the non-genotoxicity potential of the developed complexes. These results demonstrated that PS-CNPs-CU may be useful as potential delivery system.

A Novel Pyroptosis-Related Prognostic Signature for Risk Stratification and Clinical Prognosis in Clear Cell Renal Cell Carcinoma.

Emerging research has substantiated that pyroptosis-related biomarkers were mightily related to the clinical outcome of patients with clear cell renal cell carcinoma (ccRCC). However, a single-gene biomarker's moderate predictive power is insufficient, and more accurate prognostic models are urgently needed. We conducted this investigation in order to develop a robust pyroptosis-related gene signature for use in risk stratification and survival prognosis in colorectal cancer. We downloaded transcriptomic data and survival information of ccRCC patients from TCGA. Bioinformatic methods were used to generate a pyroptosis-related gene signature based on data from TCGA training cohort. ROC curve, uni- and multivariate regression analyses were used for the prognostic assays. What is more, we explored the relationship between model-based risk score and the tumor microenvironment. Herein, 11 pyroptosis-related hub genes (CASP9, TUBB6, NFKB1, BNIP3, CAPN1, CD14, PRDM1, BST2, SDHB, TFAM, and GSDMB) were determined as risk signature for risk stratification and prognosis prediction for ccRCC. Kaplan-Meier curves, ROC curves, and risk plots were employed to analyze and verify its performance in all groups. Multivariate assays exhibited that risk score could be an independent prognostic factor for patients' OS. ESTIMATE algorithm showed a higher immune score in the group of high-risk. Overall, a novel pyroptosis-related gene signature generated can be employed for prognosis prediction of ccRCC patients. This may assist in individual treatment of clinical decision-making.

MiR-133a/133b inhibits Treg differentiation in IgA nephropathy through targeting FOXP3.

OBJECTIVE: The aim of this study was to investigate the effect of miR-133a and miR-133b on regulatory T cell (Treg) differentiation in IgA nephropathy (IgAN) through targeting forkhead box P3 (FOXP3). METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from IgAN patients (n = 20) and healthy controls (n = 20). Percentage of Tregs defined as CD4 + CD25 + FOXP3 + T cells were determined by flow cytometry. The mRNA expression levels of miR-133a, miR-133b and FOXP3 were measured by real-time PCR. FOXP3 protein level was analyzed by western blotting. RESULTS: Tregs percentage in PBMCs of IgAN patients was significantly lower than that of healthy controls, whereas the expression levels of miR-133a and miR-133b in IgAN patients were dramatically higher than that in the control group. Treg percentage was negatively correlated with miR-133a and miR-133b expressions. Meanwhile, miR-133a and miR-133b modulated FOXP3 expression by detecting of its gene 3'-untranslated region. MiR-133a or miR-133b overexpression significantly decreased the % Tregs (CD4 + CD25 + FOXP3+) of the total CD4 + T cells while miR-133a or miR-133b knockdown led to an opposite effect. Moreover, FOXP3 levels in IgAN patients was significantly lower than that in the control group and was negatively correlated with miR-133a and miR-133b expression. CONCLUSION: MiR-133a and miR-133b inhibited Treg differentiation in IgA nephropathy through targeting FOXP3.

Chlorogenic Acid Attenuates Lipopolysaccharide-Induced Acute Kidney Injury by Inhibiting TLR4/NF-κB Signal Pathway.

Chlorogenic acid (CGA), a polyphenolic compound, exists widely in medicinal herbs, which has been shown a strong antioxidant and anti-inflammatory effect. This study investigated the protective effects and mechanism of CGA on lipopolysaccharide (LPS)-induced acute kidney injury (AKI). Treatment of CGA successfully ameliorates LPS-induced renal function and pathological damage. Moreover, CGA dose-dependently suppressed LPS-induced blood urea nitrogen (BUN), creatinine levels, and inflammatory cytokines TNF-α, IL-6, and IL-1ß in serum and tissue. The relative proteins' expression of TLR4/NF-κB signal pathway was assessed by western blot analysis. Our results showed that CGA dose-dependently attenuated LPS-induced kidney histopathologic changes, serum BUN, and creatinine levels. CGA also suppressed LPS-induced TNF-α, IL-6, and IL-1ß production both in serum and kidney tissues. Furthermore, our results showed that CGA significantly inhibited the LPS-induced expression of phosphorylated NF-κB p65 and IκB as well as the expression of TLR4 signal. In conclusion, our results provide a mechanistic explanation for the anti-inflammatory effects of CGA in LPS-induced AKI mice through inhibiting TLR4/NF-κB signaling pathway.