Single-cell transcriptomic analysis reveals transcript enrichment in oxidative phosphorylation, fluid sheer stress, and inflammatory pathways in obesity-related glomerulopathy.

Obesity-related glomerulopathy (ORG) is an independent risk factor for chronic kidney disease and even progression to end-stage renal disease. Efforts have been undertaken to elucidate the mechanisms underlying the development of ORG and substantial advances have been made in the treatment of ORG, but relatively little is known about cell-specific changes in gene expression. To define the transcriptomic landscape at single-cell resolution, we analyzed kidney samples from four patients with ORG and three obese control subjects without kidney disease using single-cell RNA sequencing. We report for the first time that immune cells, including T cells and B cells, are decreased in ORG patients. Further analysis indicated that SPP1 was significantly up-regulated in T cells and B cells. This gene is related to inflammation and cell proliferation. Analysis of differential gene expression in glomerular cells (endothelial cells, mesangial cells, and podocytes) showed that these cell types were mainly enriched in genes related to oxidative phosphorylation, cell adhesion, thermogenesis, and inflammatory pathways (PI3K-Akt signaling, MAPK signaling). Furthermore, we found that the podocytes of ORG patients were enriched in genes related to the fluid shear stress pathway. Moreover, an evaluation of cell-cell communications revealed that there were interactions between glomerular parietal epithelial cells and other cells in ORG patients, with major interactions between parietal epithelial cells and podocytes. Altogether, our identification of molecular events, cell types, and differentially expressed genes may facilitate the development of new preventive or therapeutic approaches for ORG.

The risk factors for arteriovenous fistula dysfunction in maintenance hemodialysis patients: A cross-sectional study.

INTRODUCTION: Arteriovenous fistula (AVF) dysfunction is a prevalent complication among maintenance hemodialysis patients. However, the factors influencing AVF patency remain unclear. To address this, we conducted a study aimed at identifying factors contributing to AVF dysfunction in this patient population. METHODS: The study compared clinical data, vascular calcification score, and laboratory data focusing on blood cell composition and coagulation in 100 maintenance hemodialysis patients in whom an AVF had been inserted from January through September of 2022. The patients were divided into a group in which the AVF functioned without issues and a group in which the AVF was dysfunctional, defined as not able to provide a blood flow of greater than 200 mL/min. FINDINGS: Patients in the 2 groups (56 in the dysfunctional AVF group and 44 in the group with satisfactory AVF function) were similar demographically. Compared with the normally functioning AVF group, the AVF dysfunction group exhibited significantly higher Agatston calcium scores (20.5 [1.28, 298] median [Q1, Q3] vs. 1.14 [0.00, 11.6]; p = 0.01), elevated triglyceride levels (1.1 [0.6, 1.2] mmol/L vs. 0.5 [0.3, 0.8]; p < 0.01), increased prothrombin activity (113 ± 22.1% vs. 99.4 ± 23.1; p < 0.01), lower prothrombin time (10.4 [9.8, 10.8] s vs. 11.0 [10.3, 11.5]; p < 0.01), higher red blood cell (RBC) counts (3.5 ± 0.7 · 1012/L vs. 3.0 ± 0.7; p < 0.01), and elevated hemoglobin levels (98.0 ± 21.8 g/L vs. 84.9 ± 24.2; p < 0.01). Higher C-reactive protein (20.2 [3.3, 20.2] mg/L vs. 17.8 [6.2, 17.8]; p = 0.01) and procalcitonin levels (0.9 [0.4, 0.9] ng/mL vs. 0.5 [0.2, 0.7]; p < 0.01) were also noted. Logistic regression analysis indicated that platelet/lymphocyte ratio, monocyte/lymphocyte ratio, and RBC count were factors associated with AVF dysfunction. Increased monocyte/lymphocyte ratio and RBC count correlated with higher risk, while a higher platelet/lymphocyte ratio was associated with lower risk. DISCUSSION: Arteriovenous fistula dysfunction in maintenance hemodialysis patients is associated with higher proportions of specific hematological parameters, particularly elevated RBC count, and altered platelet/lymphocyte and monocyte/lymphocyte ratios.

Characteristics and Prognostic Factors of SARS-CoV-2 Omicron Variant Infection in Hemodialysis Patients: A Single-Center Study in China.

INTRODUCTION: This study aimed to evaluate the characteristics and prognostic factors for coronavirus disease 2019 (COVID-19) patients on maintenance hemodialysis (HD). METHODS: All admitted HD patients who were infected with SARS-CoV-2 from December 1, 2022, to January 31, 2023, were included. Patients with pneumonia were further classified into the mild, moderate, severe, and critical illness. Clinical symptoms, laboratory results, radiologic findings, treatment, and clinical outcomes were collected. Independent risk factors for progression to critical disease and in-hospital mortality were determined by the multivariate regression analysis. The receiver operating characteristic analysis with the area under the curve was used to evaluate the predictive performance of developing critical status and in-hospital mortality. RESULTS: A total of 182 COVID-19 patients with HD were included, with an average age of the 61.55 years. Out of the total, 84 (46.1%) patients did not have pneumonia and 98 (53.8%) patients had pneumonia. Among patients with pneumonia, 48 (49.0%) had moderate illness, 26 (26.5%) severe illness, and 24 (24.5%) critical illness, respectively. Elder age [HR (95% CI): 1.07 (1.01-1.13), p <0.01], increased levels of lactate dehydrogenase (LDH) [1.01 (1.003-1.01), p <0.01], and C-reactive protein (CRP) [1.01 (1.00-1.01), p = 0.04] were risk factors for developing critical illness. Elder age [1.11 (1.03-1.19), p = 0.01], increased procalcitonin (PCT) [1.07 (1.02-1.12), p = 0.01], and LDH level [1.004 (1-1.01), p = 0.03] were factors associated with increased risk of in-hospital mortality. CONCLUSION: Age, CRP, PCT, and LDH can be used to predict negative clinical outcomes for HD patients with COVID-19 pneumonia.

Risk factors for arteriovenous fistula dysfunction in hemodialysis patients: a retrospective study.

Arteriovenous fistula (AVF) is the first choice of vascular access in hemodialysis (HD) patients. However, the correlations between patient factors and the arteriovenous fistula patency remain unclear. Therefore, our study investigates the risk factors associated with AVF dysfunction in HD patients. A total of 233 end-stage renal disease (ESDR) patients who met the study inclusion criteria in the Nephrology Department of Hunan Provincial People's Hospital between December 2020 and June 2022 were included in this study. The baseline demographic, clinical and laboratory parameters were collected at the time of AVF creation and analyzed. Of the 233 ESRD patients, 146 (62.7%) were male and the mean age was 56.11 ± 12.14 (21-82) years. The patients were followed for a median time of 14 months. Kaplan-Meier analysis showed a 6-, 12- and 24-month post-placement survival of 87.1%, 82.8% and 80.7%, respectively. Univariate Cox regression analysis revealed weight (HR, 1.03; P = 0.03) as a predictor for the loss of vascular access functionality. In addition, multivariate Cox regression analysis further demonstrated that sex (HR, 3.41; P = 0.03), weight (HR 1.08; P < 0.01) and phosphorus level (HR: 3.03; P = 0.01) are independent risk factors for AVF dysfunction. AVF dysfunction is highly associated with several risk factors including weight, phosphorus level, and sex. Positive intervention strategies targeting these potential factors, such as weight loss or oral phosphate binders could improve the long-term success of AVF.

Exosomes in Diabetic Kidney Disease.

Background: Diabetic kidney disease (DKD) is a major complication of diabetes mellitus and a common cause of end-stage kidney disease. The incidence of DKD is rising worldwide and associated with increased morbidity and premature mortality, indicating an urgent need to further explore the underlying pathogenesis and potential biomarkers. Exosomes are nanoscale vesicles secreted by all cell types that play an essential role in cellular homeostasis and intercellular communications by transferring molecular cargoes between different cells. Summary: Emerging evidence indicates that exosomes are both a crucial signaling mediator and a potential biomarker of DKD. On the one hand, exosomes released by various kidney resident cells facilitate the cell-cell crosstalk as a contributing factor in DKD; on the other hand, exosomes can be detected from urine and blood and have emerged as promising noninvasive biomarkers for DKD. Key Messages: Herein, we highlight the recent advances in research on the role of exosomes from different kidney resident cells in DKD. We further discuss the potential use of urine exosomes as biomarkers and therapeutic agents.

Heparin-induced thrombocytopenia after switching from unfractionated heparin to low-molecular-weight heparin: A case report and literature review.

Heparin-induced thrombocytopenia (HIT) is a severe, potentially life-threatening adverse drug reaction. It is an antibody-mediated process involving platelet activation. Heparin and low-molecular-weight heparin (LMWH) are routinely used in uremic patients undergoing hemodialysis. Here, we report a case of HIT that occurred in a hemodialysis patient after she switched from heparin to the LMWH nadroparin for anticoagulation during hemodialysis. The clinical features, incidence, mechanism, and treatment of HIT are discussed.

miR-128-3p inhibits high-glucose-induced peritoneal mesothelial cells fibrosis via PAK2/SyK/TGF-ß1 axis.

AIM: To elucidate the mechanism of miR-128-3p in peritoneal fibrosis (PF). METHODS: Peritoneal mesothelial cells (PMCs) were dealt with high glucose (HG) for 3 days. The expressions of miR-128-3p, p21-activated kinase 2 (PAK2), spleen tyrosine kinase (SyK), and transforming growth factor-ß1 (TGF-ß1) were detected with quantitative real-time reverse transcription polymerase chain reaction. The levels of IL-1ß, TNF-α, IL-6, and monocyte chemotactic protein-1 in supernatant were measured by ELISA. Proteins of TGF-ß1, SyK, PAK2, α-SMA, collagen I, vimentin, ERK/AP-1, and IκBα/NF-κB pathway related proteins were measured by Western blot. The correlation between miR-128-3p and PAK2 was found by bioinformatics analysis and luciferase reporter gene analysis. RESULTS: miR-128-3p was decreased while PAK2, SyK, and TGF-ß1 were increased in HG-induced PMCs. Moreover, miR-128-3p inhibited HG-induced fibrosis and inflammation in PMCs by targeting PAK2. PAK2 activated SyK, which induced TGF-ß1 expression through ERK/AP-1 and IκBα/NF-κB pathways to promote HG-induced fibrosis of PMCs. CONCLUSION: miR-128-3p inhibited HG-induced PMCs fibrosis via PAK2/SyK/TGF-ß1 axis.

Treatment of membranous nephropathy with crescent nephritis by rituximab: A case report.

BACKGROUND: Crescent formation is rare in primary membranous nephropathy (MN). The mechanism of crescent formation is unknown and the treatments are tentative. PATIENT CONCERNS: A 71-year-old woman presented with nephrotic syndrome, hematuria, and rapidly progressive kidney dysfunction. DIAGNOSIS: Kidney biopsy was performed, and the diagnosis was MN in combination with crescentic glomerulonephritis. Circulating anti-PLA2R was detected of a high level. INTERVENTIONS: The patient received rituximab besides corticosteroids. OUTCOMES: The patient achieved complete remission of proteinuria and recovery of kidney function. CONCLUSION: Our case suggests that there is a pathologic feature of MN and crescents in the absence of known immunologic factors as well as rituximab could serve as an effective cure and could be considered in serious MN conditions.

ACE2 deficiency exacerbates obesity-related glomerulopathy through its role in regulating lipid metabolism.

Obesity-related glomerulopathy is a secondary glomerular disease and its incidence has been increased globally in parallel with the obesity epidemic. ORG emerged as a growing cause of end-stage renal disease in recent years. Unbalanced production of adipokines at the adipose tissue as well as low-grade inflammatory processes play central roles in ORG progression. ORG mouse model with ACE2-knockout was generated and kidney injury was evaluated by biochemistry and histological staining assays. Protein and mRNA expressions were quantified by ELISA, western blot or qRT-PCR methods. ACE2 deficiency aggravated ORG-related renal injuries and stimulated both lipid accumulation and inflammatory responses. Further, Nrf2 pathway was deactivated upon ACE2-knockout. By contrast, ACE2 overexpression reactivated Nrf2 pathway and ameliorated ORG symptoms by decreasing fat deposition and reducing inflammatory responses. Our data demonstrated that ACE2 exerted the beneficial effects by acting through Nrf2 signaling pathway, suggesting the protective role of ACE2 against lipid accumulation and inflammatory responses in ORG pathogenesis.

Bibliometric Insights of Global Research Landscape in Mitophagy.

Background: Autophagy is a highly regulated and evolutionarily conserved process in eukaryotes which is responsible for protein and organelle degradation. Although this process was described over 60 years ago, the selective autophagy of mitochondria (mitophagy) was recently coined in 2005. Research on the topic of mitophagy has made rapid progress in the past decade, which proposed to play critical roles in human health and disease. This study aimed to visualize the scientific outputs and research trends of mitophagy. Methods: Articles and reviews related to the topic of mitophagy were retrieved from the Web of Science Core Collection on 30 November 2021. Two kinds of software (CiteSpace and VOSviewer) were used to perform a visualized analysis of countries/regions, institutions, authors, journals, references, and keywords. Results: From 2005 to 2021, total 5844 publications on mitophagy were identified for final analysis. The annual number of publications grew yearly over the past 17 years. United States (N = 2025) and Chinese Academy of Sciences is the leading country and institute (N = 112) ranked by the number of publications, respectively. The most productive author was Jun Ren (N = 38) and Derek P. Narendra obtained the most co-cited times (2693 times). The journals with the highest output and the highest co-citation frequency were Autophagy (N = 208) and Journal of Biological Chemistry (co-citation: 17226), respectively. Analyses of references and keywords suggested that "mechanism of mitochondrial quality control", "molecule and signaling pathway in mitophagy", and "mitophagy related diseases" were research hotspots, and parkin-mediated mitophagy and its roles in skeletal muscle and inflammation-related diseases may be the frontiers of future research. Conclusion: Although mitophagy research has flourished and attracted attention from all over the world, the regional imbalance in the development of mitophagy research was observed. Our results provided a comprehensive global research landscape of mitophagy from 2005- 2021 from a perspective of bibliometrics, which may serve as a reference for future mitophagy studies.

Retrospective analysis of crescent score in clinical prognosis of IgA nephropathy.

The scoring of crescents (Cs) was recently added to the Oxford classification for IgA nephropathy (IgAN). Because of the short-term use of the C score in clinical practice, its validity and applicability need to be verified. We, retrospectively, analyzed the clinicopathological data of 144 primary IgAN patients diagnosed at our hospital from March 2017 to March 2019 and with complete ≥6-month follow-up data. We found that the C score was positively correlated with the Lee's classification in the assessment of renal pathological changes and significantly correlated with increased proteinuria and decreased estimated glomerular filtration rate. Univariate Cox regression analysis showed an association of C formation with IgAN prognosis, and multivariate Cox regression indicated Cs as an independent prognosis factor. The optimal proportion of Cs for prognosis prediction by the receiver operating characteristic curve was 11%. Kaplan-Meier survival curve revealed a significantly decreased renal survival rate in patients with C proportions ≥11%. Further multivariate Cox regression analysis confirmed that the C proportion ≥11% is an independent risk factor for poor prognosis of IgAN patients. Our findings demonstrate that Cs are independently related to the prognosis of patients with IgAN, and the proportion of Cs ≥11% is an independent risk factor for poor outcomes.

Adiponectin promotes repair of renal tubular epithelial cells by regulating mitochondrial biogenesis and function.

BACKGROUND: Mitochondrial biogenesis and dysfunction are associated with renal tubular epithelial cell injury and the pathophysiological development of diabetic nephropathy (DN). Adiponectin (APN) is a plasma hormone protein specifically secreted by adipocytes. In the present study, we studied the effects of APN on mitochondrial biogenesis and function in renal tubular epithelial cells and examined the mechanisms underlying its actions. MATERIALS: A rat model of type 2 diabetes mellitus (T2DM) was established using streptozotocin (STZ), and an NRK-52E culture model exposed to high glucose was also used. We found that APN treatment alleviated kidney histopathological injury in T2DM rats, reduced fasting blood glucose (FBG) and postprandial blood glucose (PBG) levels, maintained stable animal weight, promoted cell viability, inhibited apoptosis and the formation of autophagosomes, and also increased mitochondrial mass, mitochondrial DNA (mtDNA) content and mitochondrial membrane potential (MMP) in vivo and in vitro. RESULTS: We found that the expression of AdipoR1/CREB/PGC-1α/TFAM pathway proteins and respiratory chain complex subunits CO1, CO2, CO3, ATP6 and ATP8 were significantly increased after APN treatment. We also found that inhibition of cAMP response element binding protein (CREB) weakened the effects of APN in NRK-52E cells treated with high glucose. Coimmunoprecipitation experiments showed that AdipoR1 interacted with CREB. CONCLUSION: APN promoted mitochondrial biogenesis and function in renal tubular epithelial cells by regulating the AdipoR1/CREB/PGC-1α/TFAM pathway. APN has the potential to serve as an effective drug for the treatment of DN.

IκB kinase promotes Nrf2 ubiquitination and degradation by phosphorylating cylindromatosis, aggravating oxidative stress injury in obesity-related nephropathy.

BACKGROUND: Obesity-related nephropathy (ORN) has become one of the leading causes of end-stage renal disease and has tripled over the past decade. Previous studies have demonstrated that decreased reactive oxygen species production may contribute to improving ORN by ameliorating oxidative stress injury. Here, IκB kinase (IKK) was hypothesized to inactivate the deubiquitination activity of cylindromatosis (CYLD) by activating the phosphorylation of CYLD, thus promoting the ubiquitination of NF-E2-related factor 2 (Nrf2) and further aggravating oxidative stress injury of the kidney in ORN. This study was aimed to confirm this hypothesis. METHODS: Haematoxylin and eosin (HE), periodic acid-Schiff (PAS) and Oil Red O staining were performed to assess histopathology. Dihydroethidium (DHE) staining and MDA, SOD, CAT, and GSH-PX assessments were performed to measure reactive oxygen species (ROS) production. Immunohistochemical (IHC) staining, qRT-PCR and/or western blotting were performed to assess the expression of related genes. JC-1 assays were used to measure the mitochondrial membrane potential (ΔΨm) of treated HK-2 cells. Co-immunoprecipitation experiments (Co-IP) were used to analyse the interaction between CYLD and Nrf2 in ORN. RESULTS: ORN in vivo and in vitro models were successfully constructed, and oxidative stress injury was detected in the model tissues and cells. Compared with the control groups, the phosphorylation level of CYLD increased while Nrf2 levels decreased in ORN model cells. An IKK inhibitor reduced lipid deposition, ROS production, CYLD phosphorylation levels and ΔΨm in vitro, which were reversed by knockdown of CYLD. Nrf2 directly bound to CYLD and was ubiquitinated in ORN cells. The proteasome inhibitor MG132 activated the Nrf2/ARE signalling pathway, thereby reversing the promoting effect of CYLD knockdown on oxidative stress. CONCLUSION: IKK inactivates the deubiquitination activity of CYLD by activating the phosphorylation of CYLD, thus promoting the ubiquitination of Nrf2 and further aggravating oxidative stress injury of the kidney in ORN. This observation provided a feasible basis for the treatment of kidney damage caused by ORN.

Vitamin D protects glomerular mesangial cells from high glucose-induced injury by repressing JAK/STAT signaling.

AIM: High glucose (HG) induces the production of transforming growth factor (TGF)-ß and reactive oxygen species, which further activates JAK/STAT signaling and promotes the synthesis of matrix proteins, contributes to the pathophysiological processes of diabetic nephropathy. This study aims to investigate the protection role of vitamin D (VD) in the kidney in high glucose condition. METHODS: Rat glomerular mesangial cells were cultured in high glucose medium, with or without VD or VD receptor (VDR) siRNAs treatment. The levels of TGF-ß and fibronectin were detected by qRT-PCR, immunoblotting and enzyme-linked immunosorbent assay (ELISA). The levels of phosphorylated JAK2, STAT1 and STAT3, and JAK/STAT signaling downstream genes were examined by immunoblotting and qRT-PCR. RESULTS: In rat glomerular mesangial cells, VD treatment can repress the tyrosine phosphorylation of JAK2, STAT1 and STAT3. VD inhibited TGF-ß and fibronectin expression which was rescued by vitamin d receptor (VDR) siRNA and STATs inhibitor perficitinib. The JAK/STAT signaling downstream protein coding genes including SOCS1, SOCS3 and type IV collagen were repressed by VD. Meanwhile, the expression of non-coding RNAs such as miR-181a, miR-181b, was repressed by VD, and the expression of miR-34a and Let-7b was upregulated by VD. CONCLUSION: Vitamin D (VD) treatment inhibits the function of HG on fibronectin production through regulating JAK/STAT pathway. These results provide direct evidences that VD protects glomerular mesangial cells from high glucose-induced injury through repressing JAK/STAT signaling, which has the potential for clinical DN treatment.

Risk factors for mortality in critically ill patients with COVID-19 in Huanggang, China: A single-center multivariate pattern analysis.

To date, the coronavirus disease 2019 (COVID-19) has a worldwide distribution. Risk factors for mortality in critically ill patients, especially detailed self-evaluation indicators and laboratory-examination indicators, have not been well described. In this paper, a total of 192 critically ill patients (142 were discharged and 50 died in the hospital) with COVID-19 were included. Self-evaluation indicators including demographics, baseline characteristics, and symptoms and detailed lab-examination indicators were extracted. Data were first compared between survivors and nonsurvivors. Multivariate pattern analysis (MVPA) was performed to identify possible risk factors for mortality of COVID-19 patients. MVPA achieved a relatively high classification accuracy of 93% when using both self-evaluation indicators and laboratory-examination indicators. Several self-evaluation factors related to COVID-19 were highly associated with mortality, including age, duration (time from illness onset to admission), and the Barthel index (BI) score. When the duration, age increased by 1 day, 1 year, BI decreased by 1 point, the mortality increased by 3.6%, 2.4%, and 0.9% respectively. Laboratory-examination indicators including C-reactive protein, white blood cell count, platelet count, fibrin degradation products, oxygenation index, lymphocyte count, and d-dimer were also risk factors. Among them, duration was the strongest predictor of all-cause mortality. Several self-evaluation indicators that can simply be obtained by questionnaires and without clinical examination were the risk factors of all-cause mortality in critically ill COVID-19 patients. The prediction model can be used by individuals to improve health awareness, and by clinicians to identify high-risk individuals.

The therapeutic effect of dendritic cells expressing indoleamine 2,3-dioxygenase (IDO) on an IgA nephropathy mouse model.

OBJECTIVE: IgA nephropathy (IgAN) is one of the most common glomerulonephritis in the world, especially in Asian population. IgAN usually progresses slowly, but it is still an important cause of chronic renal failure. IgAN is characterized by abnormal increase of IgA1 level and deposition in mesangium. At present, there is no specific treatment. MATERIALS AND METHODS: Previous reports have shown that DC cells expressing immunosuppressive factors can significantly reduce the symptoms of arthritis in arthritis models. Indoleamine 2,3-dioxygenase (IDO) is an important tryptophan degrading enzyme and an important factor regulating immunotolerance. DC expressing functional IDO can inhibit effector T cells by consuming essential tryptophan and/or producing toxic metabolites and promoting the differentiation of Treg cells, which exhibits immunosuppressive effect. In this study, we constructed a IgAN mouse model. The mature DC cells overexpressing IDO were induced in vitro and transfused back to IgAN mice to observe their effects on inflammation and renal injury. RESULTS: The results showed that overexpression of IDO did not affect the maturation of DC cells. The proportion of CD3 + CD4 + and CD3 + CD8 + cells decreased significantly and the proportion of CD4 + CD25 + Foxp3 + cells increased significantly in kidney tissue of IgAN mice after the reinfusion of IDO-expressing DC. The contents of IL-2, IL-4, IL-6, and IL-17A in kidney tissue of IgAN mice also decreased significantly, the damage of kidney tissue was alleviated, ACR was decreased, collagen fibre content in kidney tissue was decreased, and IgA deposition in glomerular mesangium was decreased in IgAN mice. CONCLUSIONS: It has the potential to treat IgAN by upregulating the expression of IDO in DC cells by genetic engineering and reinfusion into vivo.

Spleen Tyrosine Kinase (SYK) in the Progression of Peritoneal Fibrosis Through Activation of the TGF-ß1/Smad3 Signaling Pathway.

BACKGROUND Long-term exposure to hypertonic and high glucose in peritoneal dialysis fluid can result in peritoneal fibrosis. Spleen tyrosine kinase (SYK) has a role in inflammation and fibrosis. This study aimed to investigate the role of SYK in an in vivo rat model of peritoneal fibrosis and in rat peritoneal mesothelial cells (PMCs) in vitro and to investigate the underlying mechanisms. MATERIAL AND METHODS Sprague-Dawley rats (N=24) were randomized into the sham control group (N=6); the peritoneal fibrosis group (N=6) treated with intraperitoneal chlorhexidine digluconate; the SYK inhibitor group (N=6), treated with chlorhexidine digluconate and fostamatinib; and the TGF-ß inhibitor group (N=6), treated with chlorhexidine digluconate and LY2109761. The rat model underwent daily intraperitoneal injection with 0.5 ml of 0.1% chlorhexidine digluconate. Rat peritoneal mesothelial cells (PMCs) were cultured in vitro in high glucose. SYK expression was measured by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot. Enzyme-linked immunosorbent assay (ELISA) and qRT-PCR measured inflammatory mediators. Transforming growth factor-ß1 (TGF-ß1) and Smad3 were detected by Western blot. Short hairpin RNA (shRNA) was used to target the SYK gene. RESULTS SYK was upregulated in the rat model of peritoneal fibrosis and was induced rat PMCs cultured in high glucose. Knockdown of SYK and inhibition of TGF-ß1 significantly reduced fibrosis and inflammation. Findings in the in vivo rat model confirmed that SYK mediated peritoneal fibrosis by regulating TGF-ß1/Smad3 signaling. CONCLUSIONS In a rat model and in rat PMCs, expression of SYK increased peritoneal fibrosis through activation of the TGF-ß1/Smad3 signaling pathway.

The inhibition of Nrf2 accelerates renal lipid deposition through suppressing the ACSL1 expression in obesity-related nephropathy.

Background: Obesity has become a worldwide epidemic, and the incidence of obesity is increasing year by year. Obesity-related nephropathy (ORN) is a common kidney complication of obesity. Long-chain acyl-CoA synthetases-1, (ACSL1), is a key enzyme in the oxidative metabolism of fatty acids in mitochondria and ACSL1 may play a direct role in renal lipid deposition and promote the progress of ORN. In this study, we focus on the renoprotective role of ACSL1 in ORN. Methods: Electron microscopy, immunohistochemical (IHC) staining, Western blot, and real-time PCR were used to detect the expression of ACSL1and Nrf2 in ORN patients, ob/ob mice and palmitic acid (PA)-treated HK-2 cells. Oil red staining and Elisa Kit were used to detect the intracellular FFA and TG contents in ob/ob mice and PA-treated HK-2 cells. Dihydroethidium (DHE) staining and the MDA/SOD measurement were used to detect the ROS production. In order to demonstrate the role of ACSL1 and the interaction between ACSL1 and Nrf2 in ORN, related siRNA and plasmid were transfected into HK-2 cells. Results: More ROS production and renal lipid deposition have been found in ORN patients, ob/ob mice and PA-treated HK-2 cells. Compared with control, all the expression of ACSL1and Nrf2 were down-regulated in ORN patients, ob/ob mice and PA-treated HK-2 cells. The Nrf2 could regulate the expression of ACSL1 and the ACSL1 played the direct role in renal lipid deposition. Conclusions: The Nrf2 is inhibited in ORN, resulting more ROS production and oxidative stress. Increased oxidative stress will suppress the expression of ACSL1, which could increase the intracellular FFA and TG contents, ultimately leading to renal lipid deposition in renal tubulars and accelerating the development of ORN.

1,25-Dihydroxyvitamin D3 Prevents Epithelial-Mesenchymal Transition of HMrSV5 Human Peritoneal Mesothelial Cells by Inhibiting Histone Deacetylase 3 (HDAC3) and Increasing Vitamin D Receptor (VDR) Expression Through the Wnt/ß-Catenin Signaling Pathway.

BACKGROUND Peritoneal dialysis is the most common treatment for end-stage renal disease. However, peritoneal fibrosis resulting from long-term peritoneal dialysis restricts peritoneal ultrafiltration. Previous studies have shown a role for 1,25-dihydroxyvitamin D3 (1,25[OH]2D3) in preventing fibrosis, but the potential mechanisms remain unknown. This study aimed to investigate the role of 1,25(OH)2D3 in epithelial-mesenchymal transition (EMT) and the downstream signaling pathway in HMrSV5 human peritoneal mesothelial cells in vitro. MATERIAL AND METHODS An in vitro cell model of peritoneal fibrosis was established using the HMrSV5 human peritoneal mesothelial cell line. High glucose and lipopolysaccharide (LPS) culture conditions, with or without 1,25(OH)2D3, were used. Wnt agonist 1, a Wnt signaling pathway activator, was applied. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot were used to measure the vitamin D receptor (VDR) and histone deacetylase 3 (HDAC3) gene and protein expression levels, ß-catenin, and EMT-associated biomarkers. RESULTS High glucose plus LPS culture medium inhibited cell proliferation, induced cell apoptosis and promoted EMT in HMrSV5 cells, which was reversed by 1,25(OH)2D3 by down-regulation of HDAC3 and upregulation of VDR. HDAC3 inhibited VDR gene expression. The expression of EMT-associated biomarkers was increased by Wnt agonist 1 and inhibited by 1,25(OH)2D3. CONCLUSIONS In HMrSV5 human peritoneal mesothelial cells, 1,25(OH)2D3 reversed EMT by inhibiting the expression of HDAC3 and upregulating VDR gene expression via the Wnt/ß-catenin signaling pathway.