Epsin1-mediated exosomal sorting of Dll4 modulates the tubular-macrophage crosstalk in diabetic nephropathy.

Tubular epithelial cells (TECs) play critical roles in the development of diabetic nephropathy (DN), and can activate macrophages through the secretion of exosomes. However, the mechanism(s) of TEC-exosomes in macrophage activation under DN remains unknown. By mass spectrometry, 1,644 differentially expressed proteins, especially Dll4, were detected in the urine exosomes of DN patients compared with controls, which was confirmed by western blot assay. Elevated Epsin1 and Dll4/N1ICD expression was observed in kidney tissues in both DN patients and db/db mice and was positively associated with tubulointerstitial damage. Exosomes from high glucose (HG)-treated tubular cells (HK-2) with Epsin1 knockdown (KD) ameliorated macrophage activation, TNF-α, and IL-6 expression, and tubulointerstitial damage in C57BL/6 mice in vivo. In an in vitro study, enriched Dll4 was confirmed in HK-2 cells stimulated with HG, which was captured by THP-1 cells and promoted M1 macrophage activation. In addition, Epsin1 modulated the content of Dll4 in TEC-exosomes stimulated with HG. TEC-exosomes with Epsin1-KD significantly inhibited N1ICD activation and iNOS expression in THP-1 cells compared with incubation with HG alone. These findings suggested that Epsin1 could modulate tubular-macrophage crosstalk in DN by mediating exosomal sorting of Dll4 and Notch1 activation.

Compound Fault Diagnosis of Planetary Gearbox Based on Improved LTSS-BoW Model and Capsule Network.

The identification of compound fault components of a planetary gearbox is especially important for keeping the mechanical equipment working safely. However, the recognition performance of existing deep learning-based methods is limited by insufficient compound fault samples and single label classification principles. To solve the issue, a capsule neural network with an improved feature extractor, named LTSS-BoW-CapsNet, is proposed for the intelligent recognition of compound fault components. Firstly, a feature extractor is constructed to extract fault feature vectors from raw signals, which is based on local temporal self-similarity coupled with bag-of-words models (LTSS-BoW). Then, a multi-label classifier based on a capsule network (CapsNet) is designed, in which the dynamic routing algorithm and average threshold are adopted. The effectiveness of the proposed LTSS-BoW-CapsNet method is validated by processing three compound fault diagnosis tasks. The experimental results demonstrate that our method can via decoupling effectively identify the multi-fault components of different compound fault patterns. The testing accuracy is more than 97%, which is better than the other four traditional classification models.

4-Octyl itaconate attenuates LPS-induced acute kidney injury by activating Nrf2 and inhibiting STAT3 signaling.

BACKGROUND: Septic acute kidney injury (S-AKI) is the leading form of acute kidney failure among hospitalized patients, and the inflammatory response is involved in this process. 4-octyl itaconate (4-OI) is a multi-target itaconate derivative with potent anti-inflammatory action. However, it remains elusive whether and how 4-OI contributes to the regulation of S-AKI. METHODS: We employed a lipopolysaccharide (LPS)-induced AKI murine model and explored the potential renoprotective effect of 4-OI in vivo. In vitro experiments, BUMPT cells, a murine renal tubular cell line, were conducted to examine the effects of 4-OI on inflammation, oxidative stress, and mitophagy. Moreover, STAT3 plasmid was transfected in BUMPT cells to investigate the role of STAT3 signaling in the 4-OI-administrated state. RESULTS: We demonstrate that 4-OI protects against S-AKI through suppressing inflammation and oxidative stress and enhancing mitophagy. 4-OI significantly reduced the levels of Scr, BUN, Ngal as well as the tubular injury in LPS-induced AKI mice. 4-OI restrained inflammation by reducing macrophage infiltration and suppressing the expression of IL-1ß and NLRP3 in the septic kidney. 4-OI also reduced ROS levels, as well as cleaved caspase-3 and boosted antioxidants such as HO-1, and NQO1 in mice. In addition, the 4-OI treatment significantly promoted mitophagy. Mechanistically, 4-OI activated Nrf2 signaling and suppressed phosphorylated STAT3 in vivo and vitro. Molecular docking revealed the binding affinity of 4-OI towards STAT3. ML385, a specific Nrf2 inhibitor, partially repressed the anti-inflammatory and anti-oxidative effects of 4-OI and partially restricted the mitophagy induced by 4-OI in vivo and in vitro. Transfected with STAT3 plasmid partially suppressed mitophagy and the anti-inflammatory effect provoked by 4-OI in vitro. CONCLUSION: These data suggest that 4-OI ameliorates LPS-induced AKI by suppressing inflammation and oxidative stress and enhancing mitophagy through the overactivation of the Nrf2 signaling pathway, and inactivation of STAT3. Our study identifies 4-OI as a promising pharmacologic for S-AKI.

DsbA-L alleviates tubular injury in diabetic nephropathy by activating mitophagy through maintenance of MAM integrity.

Mitochondria-associated endoplasmic reticulum membranes (MAMs) regulate ATG14- and Beclin1-mediated mitophagy and play key roles in the development of diabetic nephropathy (DN). DsbA-L is mainly located in MAMs and plays a role in renoprotection, but whether it activates mitophagy by maintaining MAM integrity remains unclear. In the present study, we found that renal tubular damage was further aggravated in diabetic DsbA-L-/- mice compared with diabetic mice and that this damage was accompanied by disrupted MAM integrity and decreased mitophagy. Furthermore, notably decreased expression of ATG14 and Beclin1 in MAMs extracted from the kidneys of diabetic DsbA-L-/- mice was observed. In vitro, overexpression of DsbA-L reversed the disruption of MAM integrity and enhanced mitophagy in HK-2 cells, a human proximal tubular cell line, after exposure to high-glucose (HG) conditions. Additionally, compared with control mice, DsbA-L-/- mice were exhibited down-regulated expression of helicase with zinc finger 2 (HELZ2) in their kidneys according to transcriptome analysis; HELZ2 serves as a cotranscription factor that synergistically functions with PPARα to promote the expression of mitofusin 2 (MFN-2). Treatment of HK-2 cells with MFN-2 siRNA resulted in MAM uncoupling and decreased mitophagy. Moreover, HG notably reduced the expression of HELZ2 and MFN-2 and inhibited mitophagy, and these effects were partially blocked by overexpression of DsbA-L and altered upon cotreatment with HELZ2 siRNA, HELZ2 overexpression or MK886 (PPARα inhibitor) treatment. These data indicate that DsbA-L alleviates diabetic tubular damage by activating mitophagy through maintenance of MAM integrity via the HELZ2/MFN-2 pathway.

MicroRNA-122-5p ameliorates tubular injury in diabetic nephropathy via FIH-1/HIF-1α pathway.

Diabetes kidney disease (DKD) affects approximately one-third of diabetes patients, however, the specific molecular mechanism of DKD remains unclear, and there is still a lack of effective therapies. Here, we demonstrated a significant increase of microRNA-122-5p (miR-122-5p) in renal tubular cells in STZ induced diabetic nephropathy (DN) mice. Moreover, inhibition of miR-122-5p led to increased cell death and serve tubular injury and promoted DN progression following STZ treatment in mice, whereas supplementation of miR-122-5p mimic had kidney protective effects in this model. In addition, miR-122-5p suppressed the expression of factor inhibiting hypoxia-inducible factor-1 (FIH-1) in vitro models of DN. microRNA target reporter assay further verified FIH-1 as a direct target of miR-122-5p. Generally, FIH-1 inhibits the activity of HIF-1α. Our in vitro study further indicated that overexpression of HIF-1α by transfection of HIF-1α plasmid reduced tubular cell death, suggesting a protective role of HIF-1α in DN. Collectively, these findings may unveil a novel miR-122-5p/FIH-1/HIF-1α pathway which can attenuate the DN progression.

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.

The 100 top-cited articles in diabetic kidney disease: a bibliometric analysis.

BACKGROUND: Tremendous scientific researches have been conducted in the field of diabetic kidney disease (DKD), while few bibliometric analyses have been performed. We aim to identify 100 top-cited published articles about DKD and analyze their main characteristics quantitatively. METHODS: Web of Science was searched with the term 'diabetic kidney disease' OR 'diabetic nephropathy' to identify the top 100 most cited articles. For articles meeting the predefined criteria, the following data were extracted and analyzed: citation ranking, publication year, publication journal, journal impact factor, country and institution, authors, study type, and keywords. RESULTS: The highest number of citations was 4753 times. The median average citations per year was 21.8 (IQR, 16.6-33.0). Most articles focused on the pathogenesis and treatment. These articles were published in 25 different journals and the Journal of the American Society of Nephrology published the greatest number (20%). Forty-three articles (43%) originated from the United States. The University of Groningen was the leading institute, contributing five top-cited articles. The most frequent first author was de Zeeuw (n = 4), followed by Parving (n = 3). There was no correlation between the average citations and the number of authors, the number of institutes, or the number of funds, respectively. Experimental animal study was the research type most frequently conducted (n = 30), followed by observational study (n = 24). Keyword analysis revealed transforming growth factor-ß, oxidative stress, proteinuria, and renin-angiotensin-aldosterone system interruption are classic research topics. Sodium-glucose cotransporter 2 inhibitors, glucagon-like peptide 1 receptor agonists, and anti-inflammatory agents are the emerging trends of DKD. CONCLUSIONS: This bibliometric analysis helps in identifying the milestones, inadequacies, classic hotspots, and emerging trends of DKD. Pathogenesis and treatment are core themes in DKD research, while high-quality articles on the prediction and biomarker are insufficient. New analyzing metrics are needed to assess the actual impact of these top-cited articles on clinical practice.

Eradication of Microorganisms Embedding in Biofilm by a Dose-Dependent Urokinase-Based Catheter Lock Solution in Chronic Hemodialysis Patients.

INTRODUCTION: Catheter-related blood stream infection (CRBSI), the most common complication of central vein catheter (CVC), was closely associated with high morbidity and mortality in hemodialysis (HD) patients. Conjunction with systemic antibiotic, antibiotic lock (ABL) is an important therapeutic option to salvage the catheter. With extra antimicrobial and biofilm removing properties, urokinase plasminogen activator (uPA)-based ABL could have a potential role in the treatment of CRBSI. OBJECTIVE: In this study, we aimed to explore effectiveness of uPA-based (ABL) on microorganisms embedded in biofilms in vitro and CVC salvage rate in HD patients with CRBSI. METHODS: In vitro, we induced biofilms formation on the surface of HD catheter by mimicking the development of CRBSI. Applying uPA with or without antibiotics on the kinds of microorganism biofilms to explore its antimicrobial and biofilm removing properties. In vivo, 86 HD patients diagnosed as CRBSI were retrospectively enrolled to see effectiveness of uPA-based ABL on catheter salvage rate as compare to heparin-based ABL. RESULTS: uPA was effect to Staphylococcus epidermidis biofilms compared to Staphylococcus aureus, Escherichia coli, and Candida albicans. Less biofilm residues made the regrowth of S. epidermidis also limited. The combination of uPA with antibiotic showed better antimicrobial and antibiofilm activity than uPA alone or heparin-based ABL in vitro and in vivo. Among HD patients, uPA-based ABL did not cause any obvious adverse affects, and it was more effective in treating coagulase-negative Staphylococci related CRBSI than other microorganisms. CONCLUSIONS: The combination of uPA and a therapeutic plasma concentration of sensitive antibiotic can work together to effectively remove coagulase-negative S. epidermidis embedded in biofilms in vitro. uPA-based ABL is safe and effective therapeutic intervention for HD patients with CRBSI, especially compared to heparin-based ABL.

Nocardiosis in glomerular disease patients with immunosuppressive therapy.

BACKGROUND: Glomerular disease patients have a high risk of infection, which contributes to the progression of disease per se and mortality, especially in those with long-term use of glucocorticoids and (or) immunosuppressive agents. Cases of sporadic nocardiosis have been reported in glomerular disease patients, and this observation was conducted to comprehensively understand the manifestations of and treatments for nocardiosis, which is commonly misdiagnosed as pneumonia or tuberculosis or even as lung cancer or metastatic tumors in glomerular disease patients. METHODS: We reviewed the demographic characteristics, laboratory abnormalities, radiological features, and treatments of 7 patients with nocardiosis and glomerular disease receiving steroids and immunosuppression therapy at the nephrology department of the Second Xiangya Hospital between 2012 and 2019. RESULTS: It was found that all 7 patients had been receiving methylprednisolone for renal disease at a median dose of 20 mg per day and a median duration of 4 months before developing nocardiosis. There were 4 males and 3 females, and the median age was 52.14 years. All 7 patients had hypoalbuminemia at the time of admission. In addition, various cystic abscesses in the subcutaneous tissue, with or without lung and brain involvement, were observed in these patients. Encouragingly, body temperatures returned to normal, and subcutaneous abscesses diminished or disappeared with compound sulfamethoxazole treatment alone or in combination with linezolid, imipenem and mezlocillin/sulbactam. CONCLUSIONS: It was shown that multisite abscesses, including subcutaneous, pulmonary and cerebral abscesses, were the common manifestations of nocardiosis in glomerular disease patients. Sulfonamide was the first-line antibiotic therapy for nocardiosis, and combinations of other antibiotics were also needed in some serious cases.

STC-1 ameliorates renal injury in diabetic nephropathy by inhibiting the expression of BNIP3 through the AMPK/SIRT3 pathway.

Diabetic kidney disease (DKD) is the leading cause of morbidity and mortality in individuals with diabetes, and it is the leading cause of end-stage renal disease (ESRD) worldwide. Stanniocalcin-1 (STC-1) is present in various tissues, and it has antioxidant and anti-apoptotic activities, which play a role in kidney protection, including diabetic nephropathy (DN). However, the mechanism that underlies these effects remains unknown. This study suggests that STC-1 ameliorates oxidative stress and cell apoptosis in the kidneys of db/db mice and high glucose (HG)-treated BUMPT cells by inhibiting Bnip3 expression through AMPK/Sirt3 pathway activation. In the clinic, DKD patients with high levels of STC-1 have a better prognosis than patients with low STC-1 levels. Thus, we concluded that STC-1 ameliorates renal injury in DN by inhibiting the expression of Bnip3 through the AMPK/SIRT3 pathway and that serum STC-1 is independently associated with DKD progression in patients with type 2 diabetes. As high STC-1 levels indicate a better prognosis, synthetic STC-1 may become a potential drug for the treatment of DKD patients.

Loss of the Golgi Matrix Protein 130 Cause Aberrant IgA1 Glycosylation in IgA Nephropathy.

BACKGROUND: Aberrant O-glycosylation IgA1 production is a major factor in the pathogenesis of IgA nephropathy, but the underlying mechanism is still unclear. IgA1 glycosylation modification is in Golgi, and downregulation of the Golgi peripheral membrane protein Golgi matrix protein 130 (GM130) could lead to glycosylation deficiency. In this study, we aimed to explore the role of GM130 in glycosylate deficiency IgA1 (Gd-IgA1) production. METHODS: We enrolled 27 IgA nephropathy patients, 12 patients with chronic tonsillitis, 15 non-IgAN chronic kidney disease patients, and 15 healthy volunteers as healthy control. We explored GM130 expression in Tonsillar tissue by immunofluorescence staining and Western blotting and expression in peripheral blood mononuclear cells (PBMCs) by flow cytometry. The concentration of IgA1 and level of O-glycosylation were determined by ELISA and Vicia Villosa lectin-binding assay. Real-time PCR and Western blot were used to analyze the levels of ß1,3-Gal transferase (C1GALT1) and ST6GalNAC2, respectively. To explore the contribution of GM130 in IgA1 O-glycosylation modification, cells were subjected to experiments for evaluation of GM130 silencing by GM130-siRNA transfection. RESULTS: GM130 expression was significantly decreased in tonsil tissues and PBMC of IgAN patients; the expression of C1GALT1 decreased and Gd-IgA1 level increased significantly in patients with IgAN patients. The expression of GM130 was negatively related to Gd-IgA1 production. By siRNA transfection, our results clearly indicated that the downregulation of GM130 can increase IgA1 O-glycosylation deficiency, which is thought to reduce C1GALT1 expression but not affect the expression of ST6GalNAC2. CONCLUSION: We identified and demonstrated that GM130 plays an important role in IgA1 O-glycans deficiency in IgAN patients, by negatively regulating C1GALT1 expression. We believe that this finding will provide theoretical foundations for a new mechanism of Gd-IgA1 production in IgAN patients.

5-Hydroxyhexanoic Acid Predicts Early Renal Functional Decline in Type 2 Diabetes Patients with Microalbuminuria.

BACKGROUND/AIMS: Diabetic nephropathy (DN) is a leading cause of end-stage renal disease. Microalbuminuria (MA) is widely used to predict early progressive renal function decline (ERFD) of DN in type 2 diabetes mellitus (T2D) patients, but the sensitivity and specificity of MA have been questioned. Here, we determined the urine metabolites differences between T2D patients with MA who maintained stable renal function and those who progressed to ERFD in order to identify specific biomarkers of the progression of renal dysfunction. METHODS: A total of 102 T2D patients with MA and normal renal function at baseline were followed up for 5-6 years. Of these, 52 patients were selected and classified into two groups according to the later renal function; 25 patients who experienced ERFD were regarded as the progressive group, while 27 patients who maintained stable renal function were considered as the stable group. In the pilot study, untargeted, broad-spectrum urine metabolomics was performed on the urine of 12 subjects from the progressive group (5 patients as "progressors") and stable group (7 patients as "non-progressors") to discover candidate markers. We then used a targeted metabolomics analysis to identify the selected markers in the urine of an additional 40 patients (20 from the progressive group as cases, and 20 from the stable group as controls) in the validation study. RESULTS: A total of 318 known metabolites were detected in the pilot study and 6 metabolites with significant difference between progressors and non-progressors were identified. The levels of 4 metabolites, including azelaic acid, adipic acid, 5-hydroxyhexanoic acid, and L-tryptophan decreased significantly, while levels of L-pyroglutamic acid and D-norvaline increased observably in the progressors compared with non-progressors. Furthermore, in the validation study, 6 metabolites were confirmed by quantitative measurements and their concentrations were consistent with the changes in the pilot study. Concentrations of L-pyroglutamic acid and D-norvaline still increased in the cases, but were not statistically significant. Of the 4 metabolites with decreased concentrations among the cases, only 5-hydroxyhexanoic acid remained statistically significant while the other 3 metabolites did not differ between cases and controls. CONCLUSION: We have identified urine metabolites and shown that 5-hydroxyhexanoic acid can be used as a predictor of progression of ERFD in T2D patients with MA. This finding provides the new perspective that 5-hydroxyhexanoic acid may be useful to identify T2D patients with MA who are at risk of ERFD.

Initiation Condition of Hemodialysis Is Independently Associated with All-Cause Mortality in Maintenance Hemodialysis Patients: A Retrospective Study.

BACKGROUND: Despite the progression of dialysis techniques,  the mortality of hemodialysis (HD) patients is still high in China. Here, a retrospective study was performed to investigate the neglected risk factors of all-cause mortality during maintenance HD (MHD). METHODS: We investigated 117 MHD patients who died between 2011 and 2016 in the Second Xiangya Hospital of Central South University HD center. In order to analyze the risk factors of 48 months all-cause death, the methods of Kaplan-Meier and Cox regression were used. RESULTS: Multivariate analyses of adjusted age and gender showed that MHD patients with estimated glomerular filtration rate <7 or >10 mL/min/1.73 m2 and anemia (hemoglobin <100 g/L) at the initiation of dialysis are independently associated with the higher death risk. Using central venous catheter vascular access, cerebrovascular comorbidities, diabetes, low-flux dialyzer, and dialysis frequency ≤2 times weekly were also the independent risk factors of death within 48 months. CONCLUSIONS: This study indicated that the status of HD initiation is a risk factor of long-term survival in MHD patients, which were usually ignored for lacking of nephrology care prior and could potentially be identified and modified to improve the survival prognosis. Video Journal Club "Cappuccino with Claudio Ronco" at  https://www.karger.com/Journal/ArticleNews/223997?sponsor=52.

Epigallocatechin-3-Gallate Attenuates Adriamycin-Induced Focal Segmental Glomerulosclerosis via Suppression of Oxidant Stress and Apoptosis by Targeting Hypoxia-Inducible Factor-1α/ Angiopoietin-Like 4 Pathway.

BACKGROUND: Focal and segmental glomerular sclerosis (FSGS) is a common cause of nephrotic syndrome and end-stage renal disease. It has been reported that overproduction of reactive oxygen species (ROS) and cell apoptosis are associated with the development of FSGS. Epigallocatechin-3-gallate (EGCG) is a bioactive constituent accounting for more than 50% of the total catechins in green tea, which have anti-oxidative and anti-apoptotic effects. Based on this, this study was designed to evaluate the renoprotective effect of EGCG treatment on Adriamycin-induced FSGS. -Methods: In C57BL/6 mice, Adriamycin nephropathy (AN) was induced by Adriamycin (10 mg/kg body weight, diluted in normal saline) via a tail vein on day 0. Then the mice were given with EGCG (20 mg/kg body weight) or YC-1 (Lificiguat, a specific inhibitor of hypoxia-inducible factor-1α [HIF-1α], 50 mg/kg body weight) or both intraperitoneally. Both the EGCG and YC-1 were given on the day of Adriamycin injection and continued for 6 weeks. The animals were organized into the following 5 groups for the animal experiments: the control group, the AN group, the AN + EGCG group, the AN + YC-1 group and the AN + EGCG + YC-1 group. At 6 weeks, the mice were sacrificed; kidneys and blood samples were collected for further analysis. The HIF-1α and the angiopoietin-like 4 (ANGPTL4) expression were detected by Western blot, real-time PCR, immunohistochemistry or immunofluorescence. Dihydroethidium staining and NADPH oxidase 1 (Nox1) measurement were used to detect ROS production. Terminal deoxynucleotide transferase-mediated dUTP nick end-labeling (TUNEL) staining and caspase-3 measurement was used to detect cell apoptosis. RESULTS: When the animals were treated with Adriamycin, both the ROS production and TUNEL positive cells increased. Besides, the expression of HIF-1α, ANGPTL4, and caspase-3 were also up-regulated, while EGCG treatment could attenuate these changes. Interestingly, compared with treatment with YC-1 or EGCG alone, more pronounced inhibition of ANGPTL4, caspase-3 and Nox1 were obtained when YC-1 and EGCG were administered simultaneously. CONCLUSION: EGCG attenuates FSGS through the suppression of Oxidant Stress and apoptosis by targeting the HIF-1α/ANGPTL4 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.

[Clinicopathological analysis for IgA nephropathy with isolated hematuria and/or mild proteinuria].

OBJECTIVE: To investigate the correlation of different types of urinary abnormalities or different proteinuria and hematuria with the pathological injury of kidney in IgA nephropathy with isolated hematuria and/or mild proteinuria.
 Methods: Patients with primary IgA nephropathy, isolated hematuria and/or mild proteinuria were enrolled in the Department of Nephrology, the Second Xiangya Hospital, Central South University from January 2013 to January 2018. According to the difference of red blood cell count in urinary sediment and quantitative of 24-hour urinary protein (24 h-UP) during renal biopsy, the patients were grouped in 3 ways: a simple hematuria group, a hematuria and proteinuria group, and a simple proteinuria group; a proteinuria I group, a proteinuria II group, and a proteinuria III group; a hematuria I group, a hematuria II group, and a hematuria III group. The clinical parameters such as age, mean arterial pressure, blood urea nitrogen, serum creatinine, blood uric acid, 24 h-UP, and renal pathological damage were compared.
 Results: A total of 157 patients met the inclusion criteria, including 71 males and 86 females. The most common pathological type was focal and/or segmental glomerulosclerosis. The Lee's classification were dominated by grade III and IV, and the renal pathological injury was heavy. Immunoglobulin deposition was dominated by simple IgA deposition. The most common fluorescence intensity of IgA deposition was +++. 97 (61.78%) patients were accompanied by complement deposition and were mainly composed of simple complement C3 deposition. There were 18 patients (11.47%) in the simple hematuria group, 111 patients (70.70%) in the hematuria and proteinuria group, and 28 patients (17.83%) in the simple proteinuria group. Compared with the simple hematuria group, the proportion of patients with mild injury was lower in the simple proteinuria group, and the proportion of patients with moderate-to-severe injuries was increased (χ2=7.053, P=0.008). Compared with the hematuria and proteinuria group, the proportion of patients with mild injury was lower in the simple proteinuria group, and the proportion of patients with moderate-to-severe injury was increased (χ2=4.294, P=0.038). Compared with the proteinuria I group, the proportion of patients with mild injury was lower in the proteinuria III group, and the proportion of patients with moderate-to-severe injury was increased (χ2=5.433, P=0.020). There was no significant difference in the proportion of patients with renal pathological injury among different hematuria groups (P>0.05).
 Conclusion: The clinical manifestations of patients with IgA nephropathy with hematuria and/or mild proteinuria are inconsistent with renal pathological damage. Some patients with mild clinical manifestations have severe renal pathological damage and the renal pathological damage is more serious in simple proteinuria. The more proteinuria, the heavier the renal pathological damage.

Impact of GADD34 on Apoptosis of Tonsillar Mononuclear Cells from IgA Nephropathy Patients by Regulating Eif2α Phosphorylation.

BACKGROUND/AIMS: Tonsillectomy may be an important method to achieve a long-term remission of IgAN, but patients' physical status may limit their access to this surgery. We proposed an encouraging solution through inhibiting GADD34 expression in order to promote tonsillar mononuclear cells (TMCs) apoptosis and reduce nephropathic IgA secretion. METHODS: A total of 12 IgAN and 9 non-IgAN patients were involved from March 2015 to May 2016. After TMCs were extracted by density gradient centrifugation and stimulated by inactivated hemolytic streptococcus, the mRNA and protein expression of GADD34, GRP78, CHOP, Bcl-2, Bcl-XL, AID, Iα-Cα, and cleaved caspase-3 were examined by fluorescent RT-PCR and Western blotting. Guanabenz treatment and siRNA interference were applied to downregulate GADD34 in tonsillar mononuclear cells from IgAN patients, and P-eIF2α expression was examined by Western Blotting. Cell apoptosis was evaluated by Annexin V FITC/PI flowcytometry, and IgA secretion in cultural supernatant was inspected by enzyme linked immunosorbent assay. RESULTS: After stimulation, the expression of GADD34 was significantly increased in IgAN patients (P< 0.05). Cell apoptosis was mitigated and IgA secretion level was elevated (P< 0.05). To be noticed, CHOP expression had no significant difference between two groups. After guanabenz treatment and siRNA interference, a prolonged elevation of P-eIF2α expression was observed. Cell apoptosis was reinforced and IgA secretion level was decreased (P< 0.05). CONCLUSION: GADD34 may be a potential therapeutic target for IgAN treatment due to its effect on cell apoptosis.

Prediction of ESRD in IgA Nephropathy Patients from an Asian Cohort: A Random Forest Model.

BACKGROUND/AIMS: There is an increasing risk of end-stage renal disease (ESRD) among Asian people with immunoglobulin A nephropathy (IgAN). A computer-aided system for ESRD prediction in Asian IgAN patients has not been well studied. METHODS: We retrospectively reviewed biopsy-proven IgAN patients treated at the Department of Nephrology of the Second Xiangya Hospital from January 2009 to November 2013. Demographic and clinicopathological data were obtained within 1 month of renal biopsy. A random forest (RF) model was employed to predict the ESRD status in IgAN patients. All cases were initially trained and validated, taking advantage of the out-of-bagging(OOB) error. Predictors used in the model were selected according to the Gini impurity index in the RF model and verified by logistic regression analysis. The area under the receiver operating characteristic(ROC) curve (AUC) and F-measure were used to evaluate the RF model. RESULTS: A total of 262 IgAN patients were enrolled in this study with a median follow-up time of 4.66 years. The importance rankings of predictors of ESRD in the RF model were first obtained, indicating some of the most important predictors. Logistic regression also showed that these factors were statistically associated with ESRD status. We first trained an initial RF model using gender, age, hypertension, serum creatinine, 24-hour proteinuria and histological grading suggested by the Clinical Decision Support System for IgAN (CDSS, www.IgAN.net). This 6-predictor model achieved a F-measure of 0.8 and an AUC of 92.57%. By adding Oxford-MEST scores, this model outperformed the initial model with an improved AUC (96.1%) and F-measure (0.823). When C3 staining was incorporated, the AUC was 97.29% and F-measure increased to 0.83. Adding the estimated glomerular filtration rate (eGFR) improved the AUC to 95.45%. We also observed improved performance of the model with additional inputs of blood urea nitrogen (BUN), uric acid, hemoglobin and albumin. CONCLUSION: In addition to the predictors in the CDSS, Oxford-MEST scores, C3 staining and eGFR conveyed additional information for ESRD prediction in Chinese IgAN patients using a RF model.

Periplaneta Americana Extract May Attenuate Renal Fibrosis through Inhibiting Janus Tyrosine Kinase 2/Signal Transducer and Activator of Transcription 3 Pathway.

BACKGROUND: Periplaneta americana is one of the ancient insect groups with the strongest vitality. Periplaneta americana extract (PAE) has been explored as an alternative remedy for many diseases. Although much progress has been made in the study about PAE, the role of the drug in renal disease is rarely reported, especially in renal fibrosis. This study was designed to evaluate the renoprotective effect of PAE treatment to renal fibrosis. METHOD: An in vivo, unilateral ureteral obstruction (UUO) mouse model was built. Then the mice were treated with PAE (100 mg/kg body weight) once daily by oral gavage, again starting on the day of UUO and continued for 1 week. At the end of 1 week, the mice were sacrificed; kidney samples were collected for further analysis. In vitro, Boston University mouse proximal tubular cells were plated in 35-mm dishes at a density of 0.3 * 106 cells/dish. Then the cells were treated with 5-ng/mL TGF-ß1 in serum-free DMEM medium for an indicated length of time. The experimental groups were pretreated with the indicated concentrations of PAE (0.3125 mg/mL). The cells were further cultured for 24 h, and then cells were monitored morphologically or collected for biochemical analyses. RESULTS: Both in vivo and vitro PAE inhibits the expression of FN and alpha-smooth muscle actin and suppresses renal fibrosis. Importantly, PAE protects against renal fibrosis by inhibiting Janus tyrosine kinase 2 (JAK)/signal transducer and activator of transcription 3 (STAT) tyrosine phosphorylation. CONCLUSION: PAE attenuates renal fibrosis through the suppression of the JAK2/STAT3 pathway.

[Alpha-mangostin attenuates focal segmental glomerulosclerosis of mice induced by adriamycin].

OBJECTIVE: To observe the protective effect of alpha-mangostin (α-MG) on focal segmental glomurular sclerosis (FSGS) induced by adriamycin.
 Methods: Adriamycin nephropathy (AN) model was induced by adriamycin (10 mg/kg) via a tail vein. Then the mice were treated with α-MG (12.5 mg/kg) or normal salin once daily for 6 weeks. At the end of 6 weeks, the mice were sacrificed, and the kidneys and blood samples were collected. Histopathology of the kidneys were analyzed under the optical microscope. The serum levels of biochemical indicators, such as serum creatinine (SCr), blood urea nitrogen (BUN) and cholesterol were determined. The levels of superoxide anion, malondialdehyde (MDA), and glutathione (GSH), the activity of superoxide dismutase (SOD) and catalase (CAT) in kidney tissues were determined. Serum levels of IL-1ß, IL-18, IL-10 and adiponectin were determined. The levels of TGF-ß1, collagen I (Col I), α-SMA, silent information regulator 1 (Sirt1) and the nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3) in kidney tissues were determined using immunohistochemical staining, Western blot, and RT-PCR.
 Results: The levels of SCr, proteinuria, urine protein to creatinine ratio and serum cholesterol were attenuated in AN mice after α-MG treatment, while creatinine clearance rate and serum albumin were upregulated (P<0.05). α-MG treatment alleviated the glomerular and interstitial fibrosis, downregulated the expression of fibrosis markers, such as Col I and α-SMA (P<0.05). α-MG treatment reduced the production of superoxide anion, the levels of MDA and GSH, and increased the activity of CAT and SOD (P<0.05). α-MG treatment inhibitd the generation of pro-inflammatory cytokines, such as IL-1ß and IL-18 and promoted the production of anti-inflammatory cytokines, such as the IL-10 and adiponectin (P<0.05); α-MG treatment promoted the expression of Sirt1, inhibitd the expression of NLRP3 in kidney tissues (P<0.05).
 Conclusion: α-MG could attenuates FSGS of mice induced by adriamycin ameliorate and improve renal function. α-MG exerts its anti-inflammatory and anti-oxidative effects by up-regulation the expression of Sirt1 and suppression of NLRP3.