Diabetic kidney disease (DKD) progression is closely linked to the loss of podocyte homeostasis, driven in part by intracellular lipid accumulation and impaired autophagic clearance. This study identifies angiopoietin-like protein 4 (ANGPTL4) as a potential regulator of podocyte lipophagy in DKD. In renal biopsies from patients with DKD, ANGPTL4 is upregulated in podocytes, and its expression is associated with greater proteinuria and more rapid renal function decline. In immortalized human podocytes, exposure to high glucose and palmitic acid (HGPA) increases both intracellular and secreted ANGPTL4, impairs autophagic flux, and promotes lipid droplet accumulation. Mechanistically, ANGPTL4 overexpression reduces TFEB nuclear localization, increases lysosomal pH, and decreases cathepsin B and lysosomal acid lipase activities, consistent with impaired terminal lysosomal lipid degradation. Conversely, ANGPTL4 knockdown restores autophagic and lysosomal programs under HGPA conditions. Recombinant human N-terminal ANGPTL4 fragment reproduces several TFEB-localization, lysosomal, and lipophagic defects, whereas extracellular neutralization partially reverses these changes. Expression of constitutively active TFEB-S211A restores lysosomal function and lipid clearance and attenuates profibrotic remodeling. Collectively, these findings support an ANGPTL4-TFEB-associated lysosome-lipophagy pathway linking diabetic metabolic stress to defective lipid clearance and podocyte injury.
Rationale: The tertiary structure of normal podocytes prevents protein from leaking into the urine. However, observing the complexity of podocytes is challenging because of the scale differences in their three-dimensional structure and the close proximity between neighboring cells in space. In this study, we explored podocyte-secreted angiopoietin-like 4 (ANGPTL4) as a potential morphological marker via super-resolution microscopy (SRM). Methods and Results: Specimens from patients with minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), and membranous nephropathy (MN), along with normal controls, were analyzed via immunofluorescence and immunohistochemistry to determine the expression and localization of ANGPTL4, confirming its extensive presence in podocytes across both healthy and diseased conditions. Immunoelectron microscopy revealed that ANGPTL4 is distributed throughout the podocyte cell body, primary processes, and foot processes. Compared with conventional podocyte markers such as nephrin and synaptopodin, ANGPTL4 excels in depicting the three-dimensional structure of podocytes via SRM imaging. We then refined a protocol using tyramide signal amplification staining and confocal microscopy to uniformly enhance podocyte fluorescence, facilitating the clinical assessment of biopsies. In patients diagnosed with MCD and FSGS, measurements of slit diaphragm density, primary process width, and foot process width were taken after further co-staining with nephrin to identify patterns of podocyte morphological alterations. Distinctive patterns of foot process effacement were identified in MCD and FSGS patients, with FSGS patients showing more pronounced podocyte injury. Conclusions: ANGPTL4 serves as a reliable morphological marker for podocyte analysis, offering enhanced visualization of their three-dimensional structure and facilitating the identification of distinct pathological changes in nephrotic syndrome patients.
Objectives In this study, we explored the mechanism by which DDIT4 influences the polarization phenotypic transformation of macrophages and inflammation through the regulation of mTOR signaling pathway, providing a new mechanism and target for the treatment of diabetic nephropathy.Methods The degree of inflammation and injury in renal tissues of diabetic kidney disease (DKD) animal model was evaluated using biochemical assays, renal pathology examinations, and Western blot tests. Podocytes and macrophages were isolated from renal tissues to observe the extent of podocyte injury and the quantity and polarization phenotype of macrophage infiltration. Subsequently, the activated M1 macrophage model was constructed and transfected with DDIT4 to evaluate the effect of DDIT4 on the polarization phenotype transformation of macrophages and the expression of inflammatory factors. Finally, the co-culture system of macrophages and podocytes was constructed to detect the cell apoptosis, and the morphology and subcellular structure of podocin were observed by transmission electron microscopy.Results In the DKD animal model, the expression levels of inflammatory factors in renal tissues were significantly higher than those in the control group. Additionally, there was significant damage to the renal podocytes. At the same time, there was a higher number of macrophage infiltrations, predominantly of the M1 polarized phenotype. In the constructed M1 polarized macrophage model, overexpression of DDIT4 can induce the decrease of M1 macrophages and reduce the expression level of inflammatory factors. In the co-culture system of macrophages and podocytes, overexpressed DDIT4 significantly reduced the proportion of podocyte apoptosis and protect the changes of morphology and subcellular structure.Conclusions The ability of DDIT4 to mediate the transformation of macrophage phenotype and reduce inflammation reveals its potential as an innovative drug discovery target for DKD. Further exploration and validation of the therapeutic potential of DDIT4 may provide effective interventions to address unaddressed clinical needs in the treatment of DKD.
BackgroundMembranous nephropathy (MN) is an autoimmune disease and represents the most prevalent type of renal pathology in adult patients afflicted with nephrotic syndrome. Despite substantial evidence suggesting a possible link between MN and cancer, the precise underlying mechanisms remain elusive.MethodsIn this study, we acquired and integrated two MN datasets (comprising a single-cell dataset and a bulk RNA-seq dataset) from the Gene Expression Omnibus database for differential expression gene (DEG) analysis, hub genes were obtained by LASSO and random forest algorithms, the diagnostic ability of hub genes was assessed using ROC curves, and the degree of immune cell infiltration was evaluated using the ssGSEA function. Concurrently, we gathered pan-cancer-related genes from the TCGA and GTEx databases, to analyze the expression, mutation status, drug sensitivity and prognosis of hub genes in pan-cancer.ResultsWe conducted intersections between the set of 318 senescence-related genes and the 366 DEGs, resulting in the identification of 13 senescence-related DEGs. Afterwards, we meticulously analyzed these genes using the LASSO and random forest algorithms, which ultimately led to the discovery of six hub genes through intersection (PIK3R1, CCND1, TERF2IP, SLC25A4, CAPN2, and TXN). ROC curves suggest that these hub genes have good recognition of MN. After performing correlation analysis, examining immune infiltration, and conducting a comprehensive pan-cancer investigation, we validated these six hub genes through immunohistochemical analysis using human renal biopsy tissues. The pan-cancer analysis notably accentuates the robust association between these hub genes and the prognoses of individuals afflicted by diverse cancer types, further underscoring the importance of mutations within these hub genes across various cancers.ConclusionThis evidence indicates that these genes could potentially play a pivotal role as a critical link connecting MN and cancer. As a result, they may hold promise as valuable targets for intervention in cases of both MN and cancer.
Introduction:Diabetic kidney disease (DKD) necessitates innovative therapeutic strategies. This study delves into the role of DNA damage-inducing transcription factor 4 (DDIT4) within the VDR-mTOR pathway, aiming to identify a novel target for DKD drug discovery.Methods:Transcriptome data from the Gene Expression Omnibus Database were analyzed to assess the expression of mTOR and VDR expression in human renal tissues. Clinical samples from DKD patients and minimal change disease (MCD) controls were examined, and a DKD animal model using 20-week-old db/db mice was established. DDIT4 plasmid transfection was employed to modulate the VDR-mTOR pathway, with its components evaluated using immunohistochemistry, real-time quantitative PCR (qRT-PCR), Western blotting, and enzyme-linked immunosorbent assay (ELISA).Results:Changes in the expression of the VDR-mTOR pathway were observed in both DKD patients and the animal model. Overexpression of DDIT4 increased VDR expression and decreased levels of mTOR, p70s6k, and 4E-BP1. Furthermore, DDIT4 treatment regulated autophagy by upregulating LC3I expression and downregulating LC3II expression. Notably, DDIT4 alleviated oxidative stress by reducing the levels of lipid peroxidation product MDA, while simultaneously increasing the levels of superoxide dismutase (SOD) and glutathione (GSH), underscoring the role of DDIT4 in the pathological process of DKD and its potential as a therapeutic target.Conclusion:Unraveling DDIT4’s involvement in the VDR-mTOR pathway provides insights for innovative DKD drug discovery, emphasizing its potential as a therapeutic target for future interventions.
Background: This retrospective study aims to investigate the prevalence and immunopathologic characteristics of seropositive and seronegative hepatitis B virus-associated membranous nephropathy (HBV-MN). Methods: Clinicopathologic and serologic records of 420 patients with histologically confirmed HBV-MN between January 2014 and July 2021 were examined to determine the prevalence of seropositive and seronegative HBV-MN. Serum anti-PLA2R antibody testing was conducted on 280 patients with HBV-associated membranous nephropathy (HBV-MN) from August 2018 to July 2021. Immunopathologic characteristics of HBV-MN patients and anti-PLA2R antibody positivity were analyzed. Results: Among 420 pathologically confirmed HBV-MN patients, 230 (54.8%) were seropositive for HBV. The seropositive group exhibited higher blood creatinine values and incidence of liver function abnormalities than the seronegative group (p < .05). Serum anti-PLA2R antibody testing on 280 HBV-MN patients revealed a total positive rate of 44.6%, with the seronegative group showing a significantly higher rate (62.6%) compared to the seropositive group (32.1%) (p < .01). The anti-PLA2R antibody-positive group displayed higher levels of urine protein (p < .05), serum cholesterol (p < .01), and IgG4 subtypes (p < .05) compared to the negative group. Additionally, the positive group had significantly lower levels of serum albumin and IgG than the negative group (p < .01). Conclusions: This comprehensive study reveals a significantly higher prevalence of seronegative HBV-MN than previously thought. The blood creatinine values and incidence of liver function abnormalities was higher in the serology-positive group than in the serology-negative group. Notably, the seronegative group displayed a higher positive rate of anti-PLA2R antibodies compared to the seropositive group, indicating distinctive clinical and immunopathologic features.
IgA nephropathy (IgAN) is still one of the leading causes of end-stage kidney disease (ESRD), and complement system activation is a key to the pathogenesis of IgAN. The role of complement C3a/C3aR and C5a/C5aR in late stage of IgAN remains unknown. Renal specimens of 75 IgAN patients at the stage 4 CKD were stained using immunofluorescence and immunohistochemistry. The primary outcome was a composite of end-stage renal disease (ESRD) and death. Associations of complement components with baseline clinicopathological characteristics and outcomes were assessed using multivariable Cox regression and Spearman analyses. During a median follow-up of 15.0 months, 27 patients progressed to ESRD and none died. Lower eGFR [hazards ratio (HR), 0.827, 95% confidence interval (CI), 0.732-0.935; P = 0.002] and glomerular C3 deposition (HR, 3.179, 95% CI, 1.079-9.363; P = 0.036) were predictive of time to ESRD in stage 4 CKD IgAN. Higher expression of C3a (P = 0.010), C3aR (P = 0.005), C5a (P = 0.015), and C5aR (P < 0.001) was identified in ESRD group than in non-ESRD group. Glomerular C3a/C3aR and C5a/C5aR deposits were both correlated with a lower baseline eGFR, higher baseline 24 h-urinary protein (24 h-UP) and faster decline of eGFR. Besides, C3a and C5a deposits were found in patients with high S (S1) and T (T1/2) scores, respectively. Complement C3a/C3aR and C5a/C5aR in IgAN patients with stage 4 CKD may portend a faster deterioration of kidney function.
The role of complement system in late stage of IgA nephropathy (IgAN) remains unknown. We therefore investigated the effects of complement system on worsening kidney function in advanced (stage 4 CKD) IgAN. Renal specimens of 69 IgAN patients who underwent renal biopsy during stage 4 CKD between 2010 and 2021, were stained using immunofluorescence (IF) and immunohistochemistry (IHC) for glomerular complement components. The primary outcome was progression to end-stage renal disease (ESRD). Associations of complement components with baseline clinicopathological characteristics and outcomes were assessed using multivariable Cox regression and Spearman analyses. During a median follow-up of 18.0 months, 26 (37.7
Background and objectives In clinical practice, some patients are diagnosed with diabetic nephropathy (DN) combined with acute tubulointerstitial nephritis (ATIN) through renal biopsy. There is relatively little research on the treatment and prognosis of such patients, and no consensus exists on the use of glucocorticoid for treatment. Therefore, our study explores the progression of DN combined with ATIN and the renal outcomes after treatment with glucocorticoid.Methods This study retrospectively analyzed patients diagnosed with DN combined with ATIN through renal biopsy at our center from January 1, 2015, to December 31, 2021. We collected general patient information, laboratory indicators, renal pathology indicators, and the glucocorticoid usage after kidney biopsy. Follow-up data were collected from medical records. Statistical analysis methods included t-tests, non-parametric tests, and chi-square tests. Univariate and multivariate Cox regression analyses were used to evaluate the risk factors for renal endpoint events in patients. Statistical significance was defined as p-values < 0.05.Results In this study, a total of 67 patients were included. The subjects were divided into two groups based on whether they received glucocorticoid treatment: 33 patients in the steroid group and 34 in the non-steroid group. In the steroid group, 19 patients reached the renal endpoint event, which was significantly higher than in the non-steroid group (57.58% vs. 29.41%, p = 0.038). Univariate Cox regression analysis showed that serum creatinine (HR = 1.008, p < 0.001), albumin (HR = 0.919, p < 0.001), 24-h urinary protein (HR = 1.093, p = 0.002), hemoglobin (HR = 0.964, p = 0.001), triglycerides (HR = 1.12, p = 0.04), and the use of glucocorticoid (HR = 2.507, p = 0.019) were influencing factors for renal endpoint events in patients with DN combined with ATIN. Multivariate Cox regression analysis showed that albumin (HR = 0.863, p = 0.003) was an independent risk factor for renal endpoint events in patients with DN combined with ATIN.Conclusions The use of glucocorticoid in treatment does not improve renal prognosis in patients with DN combined with ATIN. Lower levels of albumin are associated with a worse renal prognosis.
Diabetic nephropathy is a prevalent complication of diabetes and stands as the primary contributor to end-stage renal disease. The global prevalence of diabetic nephropathy is on the rise, however, due to its intricate pathogenesis, there is currently an absence of efficacious treatments to enhance renal prognosis in affected patients. The mammalian target of rapamycin (mTOR), a serine/threonine protease, assumes a pivotal role in cellular division, survival, apoptosis delay, and angiogenesis. It is implicated in diverse signaling pathways and has been observed to partake in the progression of diabetic nephropathy by inhibiting autophagy, promoting inflammation, and increasing oxidative stress. In this academic review, we have consolidated the understanding of the pathological mechanisms associated with four distinct resident renal cell types (podocytes, glomerular mesangial cells, renal tubular epithelial cells, and glomerular endothelial cells), as well as macrophages and T lymphocytes, within a diabetic environment. Additionally, we highlight the research progress in the treatment of diabetic nephropathy with drugs and various molecules interfering with the mTOR signaling pathway, providing a theoretical reference for the treatment and prevention of diabetic nephropathy.
BACKGROUND:Diabetic kidney disease (DKD) is a primary microvascular complication of diabetes with limited therapeutic effects. Delving into the pathogenic mechanisms of DKD and identifying new therapeutic targets is crucial. Emerging studies reveal the implication of ferroptosis and immune dysregulation in the pathogenesis of DKD, however, the precise relationship between them remains not fully elucidated. Investigating their interplay is pivotal to unraveling the pathogenesis of diabetic kidney disease, offering insights crucial for targeted interventions and improved patient outcomes.METHODS:Integrated analysis, Consensus clustering, Machine learning including Generalized Linear Models (GLM), RandomForest (RF), Support Vector Machine (SVM) and Extreme Gradient Boosting (xGB), Artificial neural network (ANN) methods of DKD glomerular mRNA sequencing were performed to screen DKD-related ferroptosis genes.CIBERSORT, ESTIMATE and ssGSEA algorithm were used to assess the infiltration of immune cells between DKD and control groups and in two distinct ferroptosis phenotypes. The ferroptosis hub genes were verified in patients with DKD and in the db/db spontaneous type 2 diabetes mouse model via immunohistochemical and Western blotting analyses in mouse podocyte MPC5 and mesangial SV40-MES-13 cells under high-glucose (HG) conditions.RESULTS:We obtained 16 differentially expressed ferroptosis related genes and patients with DKD were clustered into two subgroups by consensus clustering. Five ferroptosis genes (DUSP1,ZFP36,PDK4,CD44 and RGS4) were identified to construct a diagnostic model with a good diagnosis performance in external validation. Analysis of immune infiltration revealed immune heterogeneity between DKD patients and controls.Moreover, a notable differentiation in immune landscape, comprised of Immune cells, ESTIMATE Score, Immune Score and Stromal Score was observed between two FRG clusters. GSVA analysis indicated that autophagy, apoptosis and complement activation can participate in the regulation of ferroptosis phenotypes. Experiment results showed that ZFP36 was significantly overexpressed in both tissue and cells while CD44 was on the contrary.Meanwhile,spearman analysis showed both ZFP36 and CD44 has a strong correlation with different immune cells,especially macrophage.CONCLUSION:The regulation of the immune landscape in DKD is significantly influenced by the focal point on ferroptosis. Newly identified ferroptosis markers, CD44 and ZFP36, are poised to play essential roles through their interactions with macrophages, adding substantial value to this regulatory landscape.
The purpose of this study was to investigate the effects of tissue fibrosis and microvessel density on shear wave–based ultrasound elastography (SWUE) of chronic kidney disease (CKD). In addition, we were looking to see whether SWUE could predict stage of CKD, correlating with the histology on kidney biopsy. Renal tissue sections from 54 patients diagnosed with suspected CKD were subjected to immunohistochemistry (CD31 and CD34), and the degree of tissue fibrosis was assessed using Masson staining. Before renal puncture, both kidneys were examined using SWUE. Comparative analysis was used to assess the correlation between SWUE and microvessel density, and between SWUE and the degree of fibrosis. Fibrosis area according to Masson staining (p < 0.05) and integrated optical density (IOD) (p < 0.05) were positively correlated with CKD stage. The percentage of positive area (PPA) and IOD for CD31 and CD34 were not correlated with CKD stage (p > 0.05). When stage 1 CKD was removed, PPA and IOD for CD34 were negatively correlated with CKD stage (p < 0.05). Masson staining fibrosis area and IOD were not correlated with SWUE (p > 0.05), PPA and IOD for CD31 and CD34 were not correlated with SWUE (p > 0.05) and, finally, no correlation between SWUE and CKD stage was found (p > 0.05). The diagnostic value of SWUE for CKD staging was very low. The utility of SWUE in CKD was affected by many factors and its diagnostic value was limited. • There was no correlation between SWUE and the degree of fibrosis, or between SWUE and microvessel density among patients with CKD. • There was no correlation between SWUE and CKD stage and the diagnostic value of SWUE for CKD staging was very low. • The utility of SWUE in CKD is affected by many factors and its value was limited.
BACKGROUND About 70%-80% of patients with primary membranous nephropathy (MN) have phospholipase A2 receptor (PLA2R) in renal tissue. Systemic light-chain (AL) amyloidosis is the most common type of amyloidosis. MN complicated with amyloidosis is rare.CASE SUMMARY A 48-year-old Chinese male presented with nephrotic syndrome, positive serum PLA2R antibody, and positive serum and urine IgG-lambda type M-protein, with a normal ratio of serum-free light-chain level. The patient was diagnosed with MN accompanied by AL amyloidosis. He was treated with rituximab with glucocorticoids and CyBorD regimen of chemotherapy. After 21 mo of follow-up, the patient achieved complete remission regarding nephrotic syndrome without adverse effects of chemotherapy.CONCLUSION We report a case of PLA2R-related MN complicated with primary AL amyloidosis only with renal involvement and successfully treated with rituximab, glucocorticoids and chemotherapy.
Background Rituximab (RTX) is a standard therapy for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). However, the most frequently used dose may lead to severe adverse effects (SAEs). We explored the efficacy and safety of low-dose RTX in Chinese patients with AAV. Methods A total of 22 Chinese patients diagnosed with AAV with renal involvement, including 8 treated with low-dose RTX (400 mg of RTX total over 4 weeks) and 14 treated with cyclophosphamide (CYC), were evaluated. The baseline clinical and pathological data and laboratory parameters during follow-up at months 1, 3, 6, and 12 were collected retrospectively. Results The baseline data showed no significant differences between the two groups. The median peripheral CD19 + cell counts in the RTX group decreased from 315.0/μL to 1.5/μL at 2 weeks, and to 2.5/μL at 1 month after the first dose. The median SCr level decreased from 267.8 μmol/L before treatment to 151.45 μmol/L at 1 month, 132.75 μmol/L at 3 months, 123.2 μmol/L at 6 months, and 151.9 μmol/L at 12 months in RTX-treated patients. The improvements in renal function, proteinuria, and ANCA titre were not significantly different between the two groups. The SAE rate was significantly lower in the RTX group (one SAE of pneumonia) compared with the CYC group. Conclusions This is the first report that low-dose RTX could be effective for the treatment of Chinese patients with AAV with renal involvement.
To investigate the prognosis of patients with spontaneous remission (SR) of phospholipase A2 receptor (PLA2R)-associated membranous nephropathy (MN). Patients diagnosed with MN were recruited after examining their renal biopsy in the Renal Department of China-Japan Friendship Hospital between January 2015 and September 2021. Among them, 24 patients with SR were included in this study and follow-up. Twenty-four patients diagnosed with SR of PLA2R-associated MN were recruited; 11 were male, and 13 were female, with a mean age of 49.5 ± 14.5 years (range, 30–77 years). The initial 24-hour urinary total protein and serum albumin levels were 0.29 ± 0.14 g/d and 37.5 ± 4.4 g/L, respectively, and the initial serum creatinine was 65.0 ± 15.8 μmol/L. During the follow-up of 33.9 ± 19.1 months (range, 6–73 months), 22 (91.7%) patients maintained remission; however, one patient had impaired renal function due to acute coronary syndrome and coronary angiography findings, and one patient experienced a repeated relapse caused by respiratory tract infection, at 50 and 70 months. A systematic review of the relevant literature was conducted, and records of patients with SR of PLA2R-associated MN were retrieved from 16 case reports or case series with a total of 97 cases. Most patients with SR of MN had a promising long-term prognosis, with only a few cases of relapse. Investigar el pronóstico de los pacientes con remisión espontánea en la nefropatía membranosa (MN, por sus siglas en inglés) asociada al receptor fosfolipasa A2 (PLA2R). Pacientes con MN diagnosticados por biopsia renal en el Departamento Renal del China-Japan Friendship Hospital entre enero de 2015 y septiembre de 2021. Entre ellos, 24 pacientes con remisión espontánea fueron reclutados y seguidos. Se reclutaron 24 pacientes con MN en remisión espontánea asociada a PLA2R; 11 varones y 13 mujeres, con una edad media de 49,5 ± 14,5 años (rango: 30-77 años) en el momento del diagnóstico. La proteína total y la albúmina sérica en orina de 24 h iniciales fueron de 0,29 ± 0,14 y 37,5 ± 4,4 g/l, respectivamente; la creatinina sérica inicial fue de 65,0 ± 15,8 μmol/l. Durante el seguimiento de 33,9 ± 19,1 (rango: 6-73) meses, 22 pacientes (91,7%) mantienen la remisión. Un paciente presentó insuficiencia renal por síndrome coronario agudo y angiografía coronaria. Otro paciente tuvo una recaída causada por una infección del tracto respiratorio 2 veces, a los 50 y 70 meses. Se realizó una revisión sistemática de la literatura. Los pacientes con MN asociada con PLA2R en remisión espontánea se recuperaron en 16 informes o series de casos, de 97 casos en total. La mayoría de los pacientes con MN en remisión espontánea tuvieron un pronóstico prometedor a largo plazo, mientras que solo unos pocos casos tuvieron recaída.
Abstract To determine the changes in the expression of DNA damage inducing transcription factor 4 (DDIT4) and the gene related to the activation of vitamin D receptor (VDR) in diabetic kidney disease (DKD) patients and experimental mice, and to explore the molecular mechanism of DDIT4 in the treatment of DKD. The pathological damage of kidney tissue and the molecular expression of VDR-mTOR related pathway in DKD patients and db/db mouse models were observed by periodate schiff (PAS) staining and immunohistochemistry (IHC) staining; furthermore, diabetic cell models were established in mouse immortalized kidney podocyte line MPC5 cells and mouse glomerular mesangial cell line SV40-MES-13 cells by high glucose culture, transfected with DDIT4 plasmid, observed cell morphological changes by transmission electron microscopy and laser confocal microscopy, and detected VDR/mTOR/p70s6k/4E-BP1 signal pathway protein expression by qRT-PCR and western blotting. PAS staining and IHC staining results showed that pathological damage of kidney tissue was observed in samples of DKD patients and in db/db mouse models. The results of qRT-PCR and western blotting showed that the expression of related proteins in VDR mTOR signal pathway changed. DDIT4 treatment could increase the expression of VDR, and reduce the expression of mTOR, p70s6k, 4E-BP1. The autophagy level showed that DDIT4 treatment could increase the expression of LC3I and decrease the expression of LC3II. The results of ferroptosis detection showed that DDIT4 treatment could reduce the expression of MDA and increase the expression of SOD and GSH. By participating in the VDR/mTOR/p70s6k/4E-BP1 signaling pathway, DDIT4 affects the process of autophagy and ferroptosis, thereby improving the pathological damage of diabetic kidney disease, and may become a new target for the treatment of DKD.
ObjectivesConverging evidence points towards a role of the complement system in the pathogenesis of diabetic nephropathy (DN). The classification system of diabetic kidney lesions devised by the Renal Pathology Society (RPS) in 2010 are based on the pathogenic process of DN. Therefore, we investigated the correlation between glomerular C3 deposits and RPS DN classification and the combined deleterious effects thereof on kidney function.MethodsThe study analyzed data from 217 diabetic patients who underwent renal biopsy between 2010 and 2021 and were found to have DN as the only glomerular disease. C3 deposition was considered positive if the glomerular C3 immunofluorescence intensity was at the trace or ≥1+ level. We divided DN into five glomerular lesion classes and separately evaluated the degree of interstitial and vascular involvement. The primary outcome was the composite of a ≥50% decline from the initial estimated glomerular filtration rate, end-stage renal disease, and death.ResultsNone of the patients were classified into class I, and few were classified into classes IIa (7.8%) and IV (9.2%). Most patients were classified as IIb (30.9%) and III (52.1%). C3 deposition was detected in 53.9% of patients. Multivariate logistic regression analysis showed that DN class was significantly correlated with C3 deposits [odds ratio, 1.59; 95% confidence interval (CI), 1.08–2.36; p = 0.02). During a median follow-up of 22 months, 123 (56.7%) patients reached the composite outcome. The endpoints occurred more frequently in patients with C3 deposition (69.2 vs. 42%) compared with those without C3 deposition. Patients with C3 deposition in either class IIb [hazards ratio (HR), 3.9 (95% CI, 1.14–13.17) vs. 2.46 (95% CI, 0.68–8.89)] or III [HR, 4.98 (95% CI, 1.53–16.23) vs. 2.63 (95% CI, 0.77–9.0)] had a higher risk of adverse kidney outcomes than those without C3 deposition. The prognostic accuracy of the combination of DN class and C3 deposits at 1 and 3 years was higher than that for DN class only.ConclusionsComplement deposition together with DN class predicts more rapid deterioration of kidney function in DN, which underlines the clinical significance of the DN phenotype according to the RPS classification.
Introduction. There has been controversy about renin-angiotensin system (RAS) inhibition in IgAN patients with advanced (stage 4) chronic kidney disease (CKD). Therefore, we investigated the effect of RAS blockade in these patients. Methods. Renal specimens of 50 IgAN patients who underwent renal biopsy during stage 4 CKD between 2010 and 2020, were stained using immunohistochemistry to detect the expression of RAS receptors (AT1R, AT2R, MasR, and MrgD). The primary endpoint was a composite of end-stage renal disease (ESRD) and death. Main baseline information and the administration of angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB) were collected. Results. During a median follow-up time of 25.5 months, 21 (42.0%) patients reached ESRD and none died. Six patients had a baseline eGFR of 15-20 ml/min/1.73m(2), and reached ESRD with a median renal survival time of 7.0 (range 6.0-23.0) months. Among patients with a baseline eGFR of 20-30 ml/min/1.73m(2), the percentage of patients using ACEI/ARB in progressive group was much lower than that in stable group (33.3% vs. 62.1%, P=0.045), together with a shorter renal survival time in progressive group (26.0 vs. 30.5 months, P=0.033). Macroproteinuria (24 h-UP & GE;2.5 g) was also associated with a shorter renal survival time, as well as a significant decline in eGFR of stable group (24.4 vs. 26.4 ml/min/1.73 m(2), P=0.026). Lower eGFR [hazards ratio (HR), 0.829, 95% confidence interval (CI), 0.724-0.950; P=0.007] and use of ACEI/ARB (HR, 0.356, 95% CI, 0.133-0.953; P=0.040) were predictive of time to ESRD in this stage. No differences were found in the expression of AT1R, AT2R, MasR, and MrgD of renal tissues at the time of biopsy between stable and progressive groups. Conclusion. Contingent on monitoring serum creatinine and potassium levels, IgAN with macroproteinuria and a GFR of 20-30 ml/min/1.73m(2) may still benefits from intrarenal RAS inhibition.
Background To investigate the relationship between membranous nephropathy (MN) and lung cancer. Methods To report patients with lung cancer detected by follow-up after the diagnosis of MN by renal biopsy in China-Japan Friendship Hospital from January 2010 to December 2019, and to study the prognosis of lung cancer-associated MN and have a review of the literature. Results Lung cancer was detected in six patients followed for 1–27 months (median 8 months) after the diagnosis of MN: including four cases of lung adenocarcinoma, one case of carcinoma in situ, and one case of small cell lung cancer with multiple metastases. Five cases were in remission after surgical resection, and one case was remitted after chemotherapy. Six patients were negative for serum anti-PLA2R antibodies, and glomerular IgG subclass deposition detected by immunofluorescence was positive for IgG1 and IgG2. Glomerular PLA2R, THSD7A, and NELL-1 stainings were assessed in all six patients; one patient was positive for glomerular PLA2R staining, two patients were positive for glomerular THSD7A staining, and all patients were negative for NELL-1 staining. A literature review of the relationship between MN and lung cancer was performed: seven articles about cancer-associated MN were searched, reporting 32 cases of MN associated with lung cancer, among which 14 cases had nephropathy as the first manifestation and only five patients had remission of MN after treatment of lung cancer. Conclusions A few lung cancer patients have nephropathy as the first clinical manifestation, and MN can also be remitted after treatment of lung cancer.