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Renal fibrosis (RF) is the key pathological feature for the progression of chronic kidney disease to end-stage renal failure. It has been an important scientific issue to understand its mechanism of RF in the field of kidney diseases in the past near two centuries. The progress of science and technology has not only provided a strong tool for RF research, but also given us many new ideas for RF prevention and treatment. The paper briefly reviews the key histories of RF research, with focuses on early studies of renal fibrosis, application of renal biopsy technology, establishment of RF animal models, advancements in cell and molecular biotechnology, and exploration into mechanisms underlying RF, to clarify future directions for chronic kidney disease prevention and treatment research.
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Objective:To observe the efficacy and safety of roxadustat in the treatment of renal anemia in calciphylaxis dialysis patients who had poor response to recombinant human erythropoietin (rHuEPO).Methods:This study was a prospective cohort study. The dialysis patients who were diagnosed with calciphylaxis and had previous regular use of rHuEPO≥3 months with hemoglobin (Hb) levels<110 g/L in the Department of Nephrology of Zhong Da Hospital affiliated to Southeast University from January 1, 2019 to March 28, 2021 were recruited. The effect of oral roxadustat in calciphylaxis dialysis patients with renal anemia was analyzed by self-comparison method.Results:There were totally 18 calciphylaxis dialysis patients with renal anemia enrolled in the study and the age was (49.7±16.2) years old, including 11 males and 7 females, and 14 cases on hemodialysis and 4 cases on peritoneal dialysis. The high-sensitivity C-reactive protein level was 27.3(15.6, 48.5) mg/L(reference value 0-3 mg/L) at baseline. The baseline Hb level was (85.4±11.6) g/L, and after 3 months of oral roxadustat, the Hb level was (105.8±15.2) g/L ( t=-9.282, P<0.001). The Hb compliance rate was 44.4%(8/18). Ferritin decreased significantly at 3 months compared with the baseline level [208.0(59.0, 306.3) μg/L vs 229.0(127.3, 385.2) μg/L, Z=-3.637, P<0.001]. The total iron binding capacity level increased significantly compared with the baseline level [127.0(65.0, 211.5) μmol/L vs 105.5(43.8, 153.7) μmol/L, Z=-2.156, P=0.031]. Transferrin saturation level at 3 months was lower than that at baseline, but there was no significant difference [20.2%(14.2%, 27.7%) vs 20.5%(18.7%, 34.9%), Z=-1.546, P=0.122]. No adverse reactions occurred during the observation period. Conclusion:The application of roxadustat can effectively correct Hb level and improve iron metabolism with high safety in calciphylaxis dialysis patients with renal anemia under inflammatory status.
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Objective To investigate whether elevated parathyroid hormone (PTH) levels could induce endothelial - to - mesenchymal transition (EndMT) and adipocyte transition in endothelial cells (ECs), and to determine the possible underlying mechanism. Methods (1) A rat model of secondary hyperparathyroidism and chronic kidney disease (CKD) was established. The adiposity in bone marrow was detected by oil red O staining. Immunofluorescence staining was performed to detect the expression and localization of cluster of differentiation 31 (CD31) and fibroblast-specific protein 1 (FSP1). (2) The human umbilical vein ECs were cultured in vitro. Western blotting was performed to detect protein expressions of EndMT-related markers CD31, FSP1 and α-smooth muscle actin (α-SMA) in interference groups with different PTH concentrations (0, 10-11, 10-9, 10-7 mol/L PTH for 48 h) and times (0, 12, 24, 48 h, 10-7 mol/L PTH), as well as the expression of β-catenin in interference groups with different PTH concentrations. The localizations of CD31, FSP1 and β - catenin were observed by cell immunofluorescence. Protein expressions of adipocytes markers peroxisome proliferator - activated receptor-γ (PPAR-γ) and CCAAT/enhancer binding protein-α (C/EBP-α) by Western blotting and the degree of adipogenesis by oil red O staining were detected after transformed ECs were cultured in adipogenic culture medium for one week. Small interfering RNA (siRNA) was performed to silenceβ - catenin expression. ECs were divided into control siRNA group, β - catenin siRNA group, PTH +control siRNA group and PTH+β-catenin siRNA group. Protein expressions of CD31, FSP1 and PPAR-γby Western blotting and the degree of adipogenesis by oil red O staining were determined. Results (1) In vivo, compared with the control, CKD rats had increased adipocytes in bone marrow (P＜0.05), and the co-expression of CD31 and FSP1 in bone marrow ECs. (2) In vitro, PTH significantly inhibited the expression of endothelial marker CD31 and increased the expressions of mesenchymal markers FSP1 and α-SMA in concentration-and time-dependent manners. These indexes in 10-7 mol/L PTH group and 0 mol/L PTH group, in 48 h group and 0 h group showed statistical differences (all P＜0.05). In PTH group ECs with 10-7 mol/L PTH for 48 h showed FSP1 accumulation in the cytoplasm and reduced expressions of CD31, and ECs had higher expressions of PPAR-γ and C/EBP-α as well as the degree of adipogenesis than those in control group (all P＜0.05). Furthermore, PTH enhanced the nuclearβ-catenin protein levels in ECs in concentration-dependent. The expressions of β-catenin in 10-7 mol/L PTH group and 0 mol/L PTH group showed statistical differences (P＜0.05). β - catenin expressed in the cytoplasm in control group, while it enter into the nucleus in PTH group. Compared with those in PTH+control siRNA group, the expressions of CD31 and PPAR-γ as well as the degree of adipogenesis decreased in PTH+β-catenin siRNA group (all P＜0.05), while the expression of FSP1 increased (P＜0.05). Conclusions PTH induces ECs - to - adipocytes transition by the canonical Wnt/β - catenin signaling pathway, which might account for bone loss in CKD. Silenced β - catenin expression can inhibit PTH-induced EndMT and adipogenesis.
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Objective To investigate the effects of nephroblastoma over-expressed protein (CCN3) on the formation of extracellular matrix (ECM) induced by transforming growth factor-β1 (TGF-β1) in human mesangial cells (HMCs) and its underlying signal transduction mechanism related with microRNA-29(miRNA-29).Methods HMCs were pretreated with different doses of exogenous CCN3 (5 μg/L,50 μg/L and 500 μg/L) or transfected with pcDNA3.1(+)-CCN3 before exposed to TGF-β1(2 μg/L),to observe the expression of fibronectin (FN),type I collagen (COL I) and miRNA-29a,b and c.The mimics or inhibitor of the miRNA-29a were transfected into HMCs to analyze whether miRNA-29a affect CCN3.The expressions of FN mRNA,COL I mRNA and miRNA-29 family were detected by real time PCR.The protein expressions of FN and COL I were detected by Western blotting and cell immunofluorescence.Results (1) Compared with the normal control group,the expressions of FN and COL I were up-regulated in TGF-β1 group,while the expressions of miRNA-29a,b,c were down-regulated in TGF-β1 group (all P ＜ 0.05).(2) Compared with the TGF-β1 group,the expressions of FN and COL I were decreased when pretreated with the different doses of exogenous of CCN3 or transfected with pcDNA3.1(+)-CCN3 (all P ＜ 0.05).Meanwhile,the expression of miRNA-29a was significantly increased when pretreated with 50 μg/L and 500 μg/L CCN3 or transfected with pcDNA3.1(+)-CCN3 (all P ＜ 0.05);whereas miRNA-29b and c had no statistical difference (all P ＞ 0.05).(3) Compared with TGF-β1+CCN3 group,the expressions of FN and COL I were decreased in CCN3+TGF-β1+miRNA-29a mimics group (all P ＜ 0.05),whereas the expressions of FN and COL I in CCN3+TGF-β1+miRNA-29a inhibitors group were increased (all P ＜ 0.05).Conclusions CCN3 reduces the TGF-β1-induced production of ECM by the up-regulation of miRNA-29a.
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Objective To investigate the effects of active vitamin D (VD) on the expression of triggering receptor expressed on myeloid cells-1 (TREM-1) in renal tissue of diabetic nephropathies (DN) rats and to explore the impact of TREM-1 on adhesion and migration capacity of macrophage.Methods DN rat models were established by streptozotocin.Rats were randomly distributed into four groups:control (NC) group,VD group,DN group and DN+VD group (DN rats with 0.1 μg · kg-1 · d-1 calcitriol by garages).Rats were sacrificed respectively at 8 weeks and 12 weeks after treatment.Pathological changes in kidney tissue were detected and the expressions of CD68 and TREM-1 were acquired by immunohistochemistry stain and Western blotting.In vitro,RAW264.7 cells were divided into NC group,VD group,high glucose (HG) group and HG+VD group.In HG+VD group rats were treated by high glucose with 10-8 mol/L 1,25(OH)2D3.TREM-1 expression was measured by immunohistochemistry stain and Western blotting,and the ability of macrophage in migration and adhesion was evaluated by Transwell migration assay and adhesion assay.TREM-1 siRNA was transferred to silence TREM-1 expression,while plasmid of TREM-1 was transferred for high expression.Their ability of adhesion and migration in macrophage and the effect of 1,25(OH)2D3 were examined.Results (1) Compared with the NC group,the expressions of CD68 and TREM-1 were increased in DN group (P ＜ 0.05),whereas markedly decreased in DN+VD group (P ＜ 0.05).(2) The number of adhesion and migration cells,and the expression of TREM-1 protein in macrophage were obviously increased in HG group as compared with those in NC group (all P ＜ 0.05);whereas above changes were markedly decreased in HG+VD group than those in HG group (P ＜ 0.05).(3) The number of adhesion and migrated macrophage was reduced after TREM-1 siRNA intervention (all P ＜ 0.05).VD could significantly decrease the effect of high glucose on adhesion and migrated macrophages after TREM-1 siRNA (all P ＜ 0.05).(4) Adhesion and migration of macrophage were increased via TREM-1 overexpression (all P ＜ 0.05),but the effects of VD on high glucose-induced adhesion and migration of macrophage were disappeared.Conclusions VD can suppress the adhesion and migration of macrophage via reducing the expression of TREM-1,and inhibit infiltration of macrophage in renal tissue of DN rats.
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Objective To investigate the effect of macrophages on podocytes apoptosis in diabetic nephropathy. Methods Differentiated mouse macrophages (RAW264.7) were exposed to normal glucose, high glucose, then the conditioned media (CM) was collected and considered as NC-CM or HG-CM, respectively. Western blotting and immunofluorescent staining were used to detect the specific markers for M1 macrophages (iNOS) and M2 macrophages (MR). ELISA was used to detect the concentration of TNF-α in the CM. Then normal PRMI 1640 media (control), NC-CM or HG-CM was added to podocytes. In some experiments, ROS inhibitors (Tempo), p38 MAPK inhibitor (SB203580), anti-TNF-α neutralizing antibody, and IgG1 isotype control were respectively added to cells with HG-CM. Besides, recombinant mouse TNF-α alone was applied to incubate podocytes. Podocytes apoptosis was accessed by Annexin V-FITC/PI and Hoechst33342 staining. DCFH-DA staining was used to analyse ROS level. Western blotting was used to detect cleaved casepase-3, p38MAPK, and p-p38MAPK protein. Results Macrophages were activated when exposed to high glucose, displaying pro-inflammatory M1 polarization with higher iNOS and lower MR expression. HG-CM but not NC-CM trigged podocytes apoptosis, up-regulated ROS, cleaved casepase-3 and p-p38MAPK. However, the podocytes apoptosis trigged by HG-CM was abolished by either a ROS inhibitor (Tempo) or a p38 MAPK inhibitor (SB203580). Additionally, TNF-α was increased in the HG-CM. TNF-α protein in macrophage was aslo increased when exposed to high glucose. Anti-TNF-α neutralizing antibody blunted the apoptotic response, excess ROS generation and p-p38 MPAK expression in podocytes induced by HG-CM. Moreover, addition of recombinant TNF-α similarly led to podocytes apoptosis, increased ROS and p38 MPAK expression. Conclusion M1 macrophages activated by high glucose released TNF-α to promote podocytes apoptosis via ROS-p38 MAPK pathway.
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Objective To investigate the potential role of CXC chemokine ligand 16 (CXCL16)/CXC chemokine receptor 6 (CXCR6) pathway in the progression of diabetic nephropathy (DN). Methods 8?week old male db/db mice were randomly divided into DN group and DN inflamed group. 10% casein was subcutaneously injected to induce the DN mouse model with inflammation. In vitro, HK?2 cells were treated with high glucose (HG), and IL?1β+HG to investigate the effect of inflammatory stress on HK?2 cells. Further knockdown CXCL16 was mediated by RNA interference to determine the effects of CXCl16, then cells were divided into HG+IL?1βgroup, HG+IL?1β + siCXCL16 group and HG + IL?1β + vehicle group. Changes of renal function in mice were assessed by 24 h proteinuria and N?acetyl?β?D?glucosaminidase (NAG) during 8 weeks. The ultra?microstructure was checked by electron microscopy at 8th week. Lipid accumulation in kidneys and HK?2 were observed by Filipin staining and quantitative assay of intracellular free cholesterol. The protein expressions of CXCl16, CXCR6, a disintegrin and metalloproteinase?10 (ADAM10), fibronectin and α smooth muscle actin (α?SMA) in renal tissue were detected by immunohistochemistry and Western blotting. The mRNA and protein expressions of CXCl16, CXCR6, ADAM10, fibronectin andα?SMA in HK?2 cells were detected by real?time PCR and Western blotting, and protein expressions of CXCl16, CXCR6 and ADAM10 in HK?2 cells were also tested by cell immunofluorescence. Results Mice in DN inflamed group had higher 24 h proteinuria and NAG than those in DN group, and the differences between two groups shown statistical significance at 8th week (all P<0.05). Compared with DN mice, DN inflamed mice had more vacuoles within renal tubular cells, with mitochondrial swelling, deformation and decrease. Lipid accumulation and protein expressions of fibronectin and α?SMA were increased in DN inflamed group when compared with DN group (all P<0.05). Further, the expressions of CXCL16, CXCR6, ADAM10 were significantly increased in DN inflamed group (all P<0.05). In vitro, the mRNA and protein expressions of CXCL16, CXCR6, ADAM10, fibronectin and α?SMA, and lipid accumulation were increased in high glucose plus IL?1βgroup when compared with high glucose group (all P<0.05). However, after siRNA of CXCL16 transfection, the mRNA and protein expressions of CXCL16, CXCR6, ADAM10, fibronectin andα?SMA were down?regulated in HG+IL?1β+siCXCL16 group as compared with high glucose+IL?1βgroup (all P<0.05). Furthermore, lipid accumulation was decreased (P<0.05). Conclusion Inflammation accelerates tubulointerstitial injury in DN partly through the activation of CXCL16 pathway, which may facilitate the lipid accumulation in tubular epithelial cells.
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Objective To evaluate the role of acute kidney injury (AKI) in predicting the early (30-day) and late (30-day to 5-year) mortality of acute myocardial infarction (AMI) patients during hospitalization.Methods A total of 1371 adult patients diagnosed with AMI in the First People's Hospital of Changzhou from January 2008 to December 2012 were analyzed retrospectively with collecting their relevant clinical data from the hospital's database.AKI was categorized according to the 2012 KDIGO AKI criteria.To compare between death group and non-death group in AMI patients during 30-day and 30-day to 5-year.Different AKI stages of patients were compared,and their all-cause mortality were analyzed by Kaplan-Meier.Using multivariate COX regression analysis with two models to assess the factors for AMI patients in 30-day to 5-year.Results The prevalence of AKI after AMI in death group was higher than that in non-death group (the 30-day prevalence was 72.7％ vs 27.4％,P ＜ 0.001;the 5-year prevalence was 36.3％ vs 26.2％,P=0.013).In both early (30-day) and late (30-day to 5-year) follow up,the KDIGO grading distribution of AKI was different between death group and non-death group (P ＜ 0.001 in 30-day follow up and P=0.002 in 30-day to 5-year follow up).Among the 1371 AMI patients,410 (29.9％) developed AKI during the hospital stay.The 30-day and 30-day to 5-year mortality rates were 5.6％ (77/1371) and 11.3％ (146/1294) respectively.All-cause mortality and cardiovascular mortality were significantly higher in patients with AKI-Ⅰ stage,AKI-Ⅱ stage and AKI-Ⅲ stage than those with non-AKI (all P ＜ 0.001),especially in patients with AKI-Ⅲ stage.Further stroke history (HR=3.122,P=0.012),AKI severity (AKI-Ⅰ stage HR=3.034,P=0.028;AKI-Ⅱ stage HR=7.832,P＜0.001;AKI-Ⅲ stage HR=9.919,P＜0.001),and β-blocker therapy (HR=0.591,P=0.040) were independent predictors of 30-day mortality,while aging (HR=1.061,P ＜ 0.001),albumin (HR=0.943,P=0.023),AKI-Ⅲ stage (HR=3.944,P=0.007),β-blocker therapy (HR=0.660,P=0.041) and percutaneous coronary intervention (HR=0.256,P ＜ 0.001) were independent predictors of 30-day to 5-year mortality.Both at early (30-day) and late (30-day to 5-year) follow-up,AKI with or without baseline renal dysfunction were independent predictors of death in patients with AMI (all P ＜ 0.05).Conclusions AKI strongly correlated with short-and long-term allcause mortality of AMI patients,regardless of the baseline renal impairment.Specifically,the more severe AKI,the higher short-term mortality AMI patients have.
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Objective To investigate the effect of 1,25(OH)2D3 on high glucose induced podocyte injury and its signal transduction mechanism.Methods Differentiated mouse podocytes were exposed to normal glucose,high glucose,and different concentrations of 1,25(OH)2D3 or LY294002 (a selective PI3K inhibitor) for 24 h.PCR and immunofluorescent staining were used to detect nephrin,podocin,and desmin.Western blotting was used to detect protein expression of nephrin,podocin,desmin,PI3K,Akt and p-Akt.Results Compared with high glucose group,1,25(OH)2D3 (100 nmol/L and 1000 nmol/L) significantly up-regulated the expression of podocin and nephrin in podocytes induced by high glucose (P ＜ 0.05).Meanwhile,1,25(OH)2D3 (100 nmol/L) significantly reduced the expression of desmin (P ＜ 0.05).PI3K and p-Akt were obviously reduced in high glucose group.In the presence of 1,25(OH)2D3,the trends were reversed.However the above effects of 1,25(OH)2D3 were abolished when p-Akt was blocked by the PI3K inhibitor LY294002.Conclusions 1,25 (OH)2D3 can inhibit high glucose-induced pedocyte injury through PI3K/p-Akt signaling pathway.
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Objective To explore the effect of irbesartan on cardiac endothelial-mesenchymal transition (EndMT) in diabetic rats.Methods The model of diabetic rat was induced by intraperitoneal injection with streptozotocin (STZ,35 mg/kg) in spontaneous hypertensive rats (SHR).Diabetic rats were divided into diabetic group and the Irbesartan treated group.The pathological changes were investigated by fluorescence microscope and electron microscope.The EndMT was studied in human aortic endothelial cells (HAEC) exposure to high glucose.The concentration of angiotensin Ⅱ in the supernatant was detected by radioimmunoassay.Immunofluorescence staining was performed to detect the co-localization of CD31 and FSP1.Results The significant myocardial fibrosis was presented in the diabetic group.Endothelial protrusions were prominent feature in myocardial microvascular of diabetic rat compared with the control group rats.Double staining of HAEC showed co-localization of CD31 and FSP1,which was decreased by the treatment of Irbesartan (P ＜ 0.05).When HAEC was exposed to high glucose,it showed some cells acquired spindle-shaped morphology and lost CD31 staining,and FSP1 and α-SMA protein expression levels were markedly upregulated,which attenuated by the treatment of Irbesartan.Conclusion Irbesartan might prevent diabetes from myocardial fibrosis via inhibition of EndMT in diabetic rats.
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Objective To investigate the effect of albumin on expression of NLRP3 inflammasome and its downstream cytokines IL-1β and IL-18 in tubular epithelial cells.Methods Thirty mesangioproliferative glomerulonephritis (MsPGN) patients with different levels of proteinuria were selected, and their renal biopsy samples were stained by PAS and Masson to observe tubular epithelial cells injury and inflammatory cells infiltration.NLRP3, caspase-1, IL-1β and IL-18, as well as different inflammatory cells, were detected by immunohistostaining.In vitro, Western blotting and real-time PCR were employed to detect NLRP3, caspase-1, IL-1β and IL-18 protein and mRNA in HK-2 cells stimulated by bovine serum albumin (BSA) (20 g/L).Results In MsPGN patients with high levels of proteinuria, there were obvious renal tubular epithelial cell injury and inflammatory cells infiltration (all P ＜ 0.05), and the expressions of NLRP3, caspase-1, IL-1β and IL-18 were up-regulated compared to patients with low levels of proteinuria (all P ＜ 0.05).Furthermore, IL-1β and IL-18expressions were positively correlated with the degree of proteinuria (r=0.836, P ＜ 0.05;r=0.901, P ＜0.05).NLRP3, caspase-1, IL-1β and IL-18 protein and mRNA were significantly increased in HK-2cells stimulated by BSA compared to the control group (all P ＜ 0.05).Conclusions Albumin is able to induce NLRP3 inflammasome activation in tubular epithelial cells, which may be the mechanism of tubulointerstitial injury and inflammation caused by proteinuria.
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Objective To investigate the risk factors of acute kidney injury (AKI) in patients after acute myocardial infarction (AMI).Methods A total of 1 371 adult patients diagnosed AMI in the First People's Hospital of Changzhou from January 2008 to December 2012 were analyzed retrospectively.AKI was defined according to the 2012 KDIGO AKI criteria.Based on the occurrence of AKI,the patients were divided into AKI group and non-AKI group.According to the AKI timing,the patients were divided into subgroups including conservative treatment groups,coronary angiography (CAG) groups and coronary artery bypass grafting (CABG) groups,respectively.Related risk factors of AKI were analyzed by univariate and multivariate logistic regression.Results Of the 1 371 patients,410(29.9％) developed AKI.Compared to the non-AKI group,in-hospital mortality increased significantly in the AKI group (17.1％ vs 3.9％,x2=68.0,P ＜ 0.001).Multifactor retrospective analysis showed that decreased baseline eGFR (OR=2.049,95％ CI:1.246-3.370),increased fasting plasma glucose(FPG) (OR=1.070,95％CI:1.018-1.124),diuretics (OR=1.867,95％CI:1.220-2.856) and Killip class 4 status (OR=1.362,95％ CI:1.059-3.170) were all independent risk factors of AKI,while increased DBP on admission was a protective factor (OR=0.986,95％ CI:0.974-0.998) for the conservative management group.Decreased baseline eGFR (OR=2.371,95％CI:1.500-3.747),increased FPG(OR=1.009,95％CI:1.005-1.012),diuretics (OR=1.674,95％CI:1.042-2.690),intraoperative hypotension (OR=2.276,95％ CI:1.324-3.575) and acute infection (OR=1.678,95％CI:1.023-2.754) were independent risk factors of AKI for the CAG group.Decreased baseline eGFR (OR=2.246,95％CI:1.340-3.981),increased FPG (OR=1.059,95％CI:1.018-1.124),diuretics (OR=1.723,95％CI:1.122-2.650),and low cardiac output syndrome after operation (OR=2.331,95％ CI:1.277-3.286) were independent risk factors of AKI for CABG group.Conclusions AKI is a common complication and associated with increased mortality after AMI.Decreased baseline renal function,increased FPG and diuretics were common independent risk factors of AKI after AMI.
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Objective To investigate the effects of low density lipoprotein receptor (LDLr) pathway on podocyte injury in diabetic nephropathy (DN) under inflammatory stress.Methods Male db/db mice and db/m mice were randomly divided into four groups (8 mice in each group):db/m group (control),casein injected db/m group (db/m + casein),db/db group (db/db),and casein injected db/db group (db/db + casein).An inflamed model of DN was established according to our previous study.24-hour urinary protein was measured every week.The plasma lipid profile was detected by clinical biochemistry assay.Podocyte changes were evaluated by electron microscope and immunofluorescent staining.Lipid accumulation in the kidney was evaluated by oil red O staining and intracellular cholesterol quantitative assay.The protein expression of Wilm's tumor-1 (WT-1),nephrin,α-smooth muscle actin (t-SMA),and molecules correlated with LDLr pathway were examined by immunohistochemical staining or Western blotting.The colocalized protein expression of LDLr with WT-1 was examined by immunofluorescent staining and laser confocal microscopy.Results There were no differences in plasma levels of LDL and HDL among four groups.Compared with db/db group,the db/db+ casein group showed markedly increased 24-hour urinary protein,more significant podocyte foot process effacement and podocyte damage,increased lipid droplet accumulation in kidneys,increased protein expressions of LDLr,SCAP and SREBP-2 in kidneys (all P ＜ 0.05).Interestingly,increased LDLr protein expression in kidneys of db/db mice was negatively correlated with decreased nephrin protein expression (r =-0.855,P ＜ 0.01) and positively correlated with increased α-SMA protein expression (r=0.768,P ＜ 0.01).Conclusions The disruption of LDLr pathway induced by inflammation contributes to podocyte injuries in diabetic nephropathy.
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Objective To observe NLRP3 inflammasome expression and inflammatory cells infiltration in the BSA-overloaded rats kidney,and to investigate the potential mechanism of renal injury induced by proteinuria.Methods After unilateral right nephrectomy,eighteen healthy male Wistar rats were randomly divided into two groups:protein overload nephropathy model group (n=10),treated with intraperitoneal injections of bovine serum albumin (BSA); control group (n=8),treated with intraperitoneal injections of 0.9％ saline for 9 weeks.Body weigh were measured every week and 24 h urine were collected in 0,2,5,7,9 week.The plasma levels of blood total protein (TP),albumin (Alb),serum creatinine (Scr) and blood urea nitrogen (BUN) were determined by automatic analyzers.Renal pathological changes were evaluated by PAS and Masson stains.Immunohistochemical staining was used to detect the expression of NLRP3,caspase-1,IL-1β,and IL-18,as well as the types of inflammatory cells.The NLRP3,caspase-1,IL-1β,and IL-18 protein and mRNA levels were also analyzed by Western blot and real-time PCR in two groups.Results It was found that there was a significant increase of proteinuria and BUN in model group compare to that in control group (all P ＜ 0.05).However,there were no significant changes in body weight,TP,Alb and Scr between the two groups.Morphological study demonstrated that renal tubular epithelial cell injury,proteinaceous casts in tubular lumen,accompanying with the dominant macrophages and lymphocytes infiltration in interstitium in model group.The immunohistochemistry showed that there were more T (CD3+),B cells (CD20+) and macrophages (CD68+) in renal interstitium in model group than that in control group (P ＜ 0.05).Tubulointerstitial injury score was higher than that of the control group (P＜0.05).Immunohistochemistry,Western blot and real-time PCR all showed that the expression of NLRP3,caspase-1,IL-18 and IL-1 β were significantly increased compared to those in control group (P ＜ 0.05).Furthermore,there were significant correlations between proteinuria and IL-lβ/IL-18 expression (P ＜ 0.05).Conclusion NLRP3 inflammasome activation is involved in tubulointerstitial inflammation caused by proteinuria.
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<p><b>BACKGROUND</b>The efficacy and safety of immunosuppression for idiopathic membranous nephropathy (IMN) are still controversial. Recent studies showed tacrolimus is effective in the treatment of IMN. To evaluate the efficacy and safety of tacrolimus (TAC) for IMN, we conducted a meta-analysis of published medical literatures.</p><p><b>METHODS</b>Studies addressing the effect of tacrolimus in IMN were searched on PUBMED, EMBASE, The Cochrane Library, and ClinicalTrials.gov (March 2013). Trials comparing tacrolimus with corticosteroid versus control group (cyclophosphamide with corticosteroid) were included. The quality of the studies was assessed using Jadad method. Statistical analyses were performed using Review Manager 5.2 and the results were summarized by calculating the risk ratio (RR) for dichotomous data or the mean difference (MD) for continuous data with 95% confident interval (CI).</p><p><b>RESULTS</b>A total of four studies (259 patients) were included. It was shown that therapy with tacrolimus plus corticosteroid had a higher complete remission rate compared to therapy with cyclophosplamide plus corticosteroid (RR = 1.53, 95% CI: 1.05-2.24, P < 0.05), but not significant on total remission, partial remission and adverse effects. Also, no significant alterations were observed in proteinuria and serum albumin level between the two groups. During the entire follow-up period, serum creatinine level remained stable in both groups without = 50% increase in its level.</p><p><b>CONCLUSIONS</b>TAC is more effective than cyclophosphamide (CTX) by achieving complete remission in patients with IMN. Multi-ethnic RCTs are needed to evaluate its long-term efficacy and safety.</p>
Subject(s)
Humans , Adrenal Cortex Hormones , Therapeutic Uses , Cyclophosphamide , Therapeutic Uses , Glomerulonephritis, Membranous , Drug Therapy , Immunosuppressive Agents , Therapeutic Uses , Tacrolimus , Therapeutic UsesABSTRACT
Objective To explore whether high glucose (HG)-induced endothelial-to-mesenchymal transition (EndMT) could be transitioned into mesenchymal stem cells (MSCs) and further differentiated into chondrocytes.Methods Human aortic endothelial cells (HAECs) were divided into three groups:normal glucose (NG,5.5 mmol/L glucose) group,HG (30 mmol/L glucose) group,and mannitol (5.5 mmol/L glucose + 24.5 mmol/L mannitol) group,and were cultured for 48 h.Immunofluorescence staining was performed to detect the co-expression of CD31 (endothelial markers),and fibroblast-specific protein 1 (FSP1,fibroblast markers).The expression of CD31 and FSP1 mRNA and protein was detected by real-time PCR and Western blotting.When endothelial-derived MSCs were grown in MSC medium for one week,the expression of the MSCs markers CD44,CD10 and the chondrocyte marker SOX9 was detected by Western blotting and RT-PCR.Chondrocyte expression was detected by alcian blue staining.Calcium deposit was analyzed by alizarin red staining.Pathological changes were investigated using electron microscopy.Results The expression of FSP1 mRNA and protein was significantly increased,but the expression of CD31 mRNA and protein was decreased (P ＜0.01),and the cells undergoing EndMT also significantly expressed CD10,CD44 and SOX9 in the HG group compared with those in normal glucose group (P ＜ 0.01).The incubation of HAECs exposed to HG resulted in a fibroblast-like phenotype,wherein increased microfilamentation and a roughened endoplasmic reticulum structure were observed in the cytoplasm.Double staining of the HAECs indicated a co-localization of CD31 and FSP1.After one week culture for chondrocyte medium,the expression of MSCs marker STRO-1 was significantly increased by immunofluorescence staining.Additionally,aleian blue staining in the HG group was positive compared to the NG group.Consistent with the elevation of SOX9 expression,calcium deposit also enhanced in the HG group.Conclusion HG can induce endothelial cells transdifferentiation into chondrocyte-like cells via the EndMT.
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Objective To investigate the effect of Cordyceps sinensis on renal fibrosis and its possible mechanism.Methods Thirty Sprague-Dawley rats were randomly divided into three groups:Sham operation group (Sham,n =10),5/6 subtotal uephrectomy group (SNx,n =10),and 5/6subtotal nephrectomy treated with Cordyceps sinensis group (CS,n =10).Body weights were assessed and 24-hour urine excretion was collected before and every four weeks after surgery.Rats were sacrificed at 12 weeks after surgery.Blood samples were taken for biochemical study,and kidney tissues were used for HE and Masson stains to assess histological changes.Immunohistochemical staining was used to detect the expression of transforming growth factor β1 (TGF-β1) and its receptors of type Ⅰ (TβR Ⅰ),type Ⅱ (TβR Ⅱ).Immunofluorescence was used to detect E-cadherin and α-SMA.The relative protein level of TGF-β1,TβR Ⅰ,TβR Ⅱ,p-Smad2/3,Smad7,E-cadherin,α-SMA were examined by Western blotting.Results CS group had higher body weights and lower urinary protein,BUN and Scr level compared with SNx group.Glomerulosclerosis index and tubulointerstitial injury score were significantly reduced in CS group compared with those in SNx group (all P ＜ 0.05).The protein expressions of TGF-β1,TβR Ⅰ,TβR Ⅱ,p-Smad2/3 were decreased in CS group compared with those in SNx group (all P ＜ 0.05).CS treatment up-regulated the expression of E-cadherin,Smad7 and down-regulated the expression of α-SMA compared with that in SNx group (all P ＜ 0.05).Conclusion Cordyceps sinensis has inhibitory effect on renal fibrosis in 5/6 subtotal nephrectomy rat model,which might be related with the suppression of TGF-β 1 signal pathway.
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Objective To investigate the effects of angiotensin Ⅱ (Ang Ⅱ) stimulating on cholesterol influx in human renal proximal tubular epithelial cells (HK-2) and the relation to low-density lipoprotein receptor (LDLr) pathway.Methods HK-2 cells were cultured and divided into the control group (incubated with serum-free medium) and Ang Ⅱ group (treated by 10-7 mol/L of Ang Ⅱ for 24 hours).The effects of Ang Ⅱ on lipid accumulation were examined by Oil red O staining and a quantitative assay of intracellular cholesterol.The expression of LDLr,sterol regulatory elementbinding protein (SREBP) cleavage activating protein (SCAP) and SREBP-2 mRNA and protein were examined by real-time PCR and Western blotting.The cotranslocation of SCAP-SREBP-2 from endoplasmic retieulum to Golgi in HK-2 cells was examined by immunofluorescent staining under confocal microscopy.Results Ang Ⅱ treatment increased intracellular lipid accumulation in HK-2 cells,which was associated with increased mRNA and protein expression of LDLr,SCAP,and SREBP-2 in HK-2 cells induced by Ang Ⅱ.Furthermore,results from confocal microscopy observation demonstrated that Ang Ⅱ increased the translocation of SCAP/SREBP-2 complex from endoplasmic reticulum to Golgi,thereby up-regulating LDLr gene transcription.Conclusion Ang Ⅱ disrupts LDLr feed-back regulation to increase cholesterol uptake and induce intracellular lipid accumulation.
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Objective To investigate whether low density lipoprotein receptor (LDLr) pathway involves in the progression of vascular calcification (VC) in hemodialysis patients under microinflammation.Methods Twenty-eight hemodialysis patients were divided into control and inflammation group according to plasma C-reactive protein level.Surgically removed tissues from radial artery of patients receiving arteriovenostomy were used in experiments.Foam cell formation and calcification deposition were observed by hematoxylin-eosin (HE) and alizarin red S staining respectively.VC-related protein expression,such as bone morphogenetic proteins-2 (BMP-2),collagen Ⅰ,alkaline phosphatase (ALP),and LDLr and its related nuclear factor of transcriptional regulation,such as sterol regulatory element binding protein-2 (SREBP-2) and SREBP cleavage-activating protein (SCAP),were detected by immunohistochemistry and immunofluorescence staining.Results HE and alizarin red S staining showed that there were parallel increased foam cell formation and calcium deposit in continuous cross-sections of radial arteries in inflammation group compared to control group,which were closely correlated with increased protein expressions of LDLr,SREBP-2,BMP-2,and collagen Ⅰ as shown by immunohistochemical and immunofluorescent staining.Confocal microscopy confirmed that inflammation enhanced the translocation of SCAP/SREBP-2 complex from endoplasmic reticulum to Golgi,thereby activating LDLr gene transcription.Inflammation increased protein expression of ALP and reduced protein expression of alpha-smooth muscle actin,contributing to the phenotype conversion of vascular smooth muscle cells in calcified vessels from the fibroblastic to the osteogenic,which were the main cell components in VC.Further analysis showed that the disruption of LDLr pathway induced by inflammation was positively correlated with the enhanced expression of BMP-2 and collagen Ⅰ (r=0.782,P＜0.01; r=0.644,P＜0.05).Conclusion Inflammation accelerates the progression of VC in hemodialysis patients through the disruption of LDLr feedback regulation.
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Objective To evaluate the efficacy and safety of continuous erythropoietin receptor activator (C.E.R.A.) once every 4 weeks by subcutaneous administration on hemoglobin (Hb)maintenance in dialytic patients with chronic renal anemia who had been treated with stable dose of erythropoietin (EPO).Methods This was an open,randomized,controlled,multi-center trial.All the hemodialysis or peritoneal dialytic patients in EPO maintenance treatment received subcutaneous EPO-β during the 6-week pre-treatment period to maintain Hb level between 100 g/L and 120 g/L.Eligible patients were randomized (2∶1 ) to accept either C.E.R.A.once every 4 weeks by subcutaneous administration ( C.E.R.A.group,n =187 ) or subcutaneous EPO-β 1-3 times weekly ( EPO group,n =94) for 28 weeks (including 20-week dose titration period and 8-week efficacy evaluation period ). The starting dose of C.E.R.A.was converted according to the dose of EPO-β administered in the week preceding the first study drug administration.The primary outcome was the change of Hb level between the baseline and that in the efficacy evaluation period.Results Totally 253 patients completed the whole 28-week treatment.The change of baseline-adjusted mean Hb was +2.57 g/L for C.E.R.A.group and + 1.23 g/L for EPO group,resulting in a treatment difference of 1.34 g/L (95％ CI - 1.11-3.78 g/L).Since the lower limit of 95％ CI was greater than the pre-defined non-inferiority margin -7.5 g/L( P ＜ 0.0001 ),C.E.R.A.once every 4 weeks by subcutaneous administration was clinically non-inferior to EPO regarding the maintenance of stable Hb level.The proportion of patients maintaining Hb level within the range of 100-120 g/L through efficacy evaluation period was similar between the two groups ( 69.0％ for C.E.R.A.group vs 68.9％ for EPO group,P ＞0.05 ).The overall incidence of adverse events was similar between the C.E.R.A.(41.7％)and EPO (46.2％ ) groups ( P ＞ 0.05 ).The safety findings were in accordance with the patients' primary diseases rather than the administration.Conclusions Conversion from EPO to C.E.R.A.once every 4 weeks by subcutaneous injection could maintain the Hb in target level in dialytic patients with renal anemia,and it was non-inferior to EPO.In general,subcutaneous administration of C.E.R.A.is well tolerated in dialytic patients with chronic renal anemia.