Kidney tea [Orthosiphon aristatus (Blume) Miq.] improves diabetic nephropathy via regulating gut microbiota and ferroptosis.

Introduction: Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. Due to its complex pathogenesis, new therapeutic agents are urgently needed. Orthosiphon aristatus (Blume) Miq., commonly known as kidney tea, is widely used in DN treatment in China. However, the mechanisms have not been fully elucidated. Methods: We used db/db mice as the DN model and evaluated the efficacy of kidney tea in DN treatment by measuring fasting blood glucose (FBG), serum inflammatory cytokines, renal injury indicators and histopathological changes. Furthermore, 16S rDNA gene sequencing, untargeted serum metabolomics, electron microscope, ELISA, qRT-PCR, and Western blotting were performed to explore the mechanisms by which kidney tea exerted therapeutic effects. Results: Twelve polyphenols were identified from kidney tea, and its extract ameliorated FBG, inflammation and renal injury in DN mice. Moreover, kidney tea reshaped the gut microbiota, reduced the abundance of Muribaculaceae, Lachnoclostridium, Prevotellaceae_UCG-001, Corynebacterium and Akkermansia, and enriched the abundance of Alloprevotella, Blautia and Lachnospiraceae_NK4A136_group. Kidney tea altered the levels of serum metabolites in pathways such as ferroptosis, arginine biosynthesis and mTOR signaling pathway. Importantly, kidney tea improved mitochondrial damage, increased SOD activity, and decreased the levels of MDA and 4-HNE in the renal tissues of DN mice. Meanwhile, this functional tea upregulated GPX4 and FTH1 expression and downregulated ACSL4 and NCOA4 expression, indicating that it could inhibit ferroptosis in the kidneys. Conclusion: Our findings imply that kidney tea can attenuate DN development by modulating gut microbiota and ferroptosis, which presents a novel scientific rationale for the clinical application of kidney tea.

Clinical characteristics of membranous nephropathy after allogeneic hematopoietic stem cell transplantation: A real-world multicenter study.

Membranous nephropathy (MN) is a rare complication that can occur after allogeneic hematopoietic stem cell transplantation (allo-HSCT). MN patients may develop nephrotic syndrome or even kidney failure, which greatly affects their quality of life and prognosis. However, current knowledge regarding MN after allo-HSCT is limited. Thus, a multicenter nested case‒control study was conducted. Patients who had been diagnosed with MN after allo-HSCT were retrospectively identified at 8 HSCT centers. A total of 51 patients with MN after allo-HSCT were included. The median age of MN patients after allo-HSCT was 38 years, and the median duration from HSCT to MN was 18 months. The use of HLA-matched donors (P = 0.0102) and peripheral blood as the graft source (P = 0.0060) were identified as independent predisposing risk factors for the onset of MN after allo-HSCT. Compared to those in the control group, the incidence of extensive chronic graft-versus-host disease was greater in the MN patients (P = 0.0002). A total of 31 patients developed nephrotic syndrome. Patients receiving combination treatments of corticosteroids and immunosuppressants appeared to have better outcomes. In conclusion, MN is a rare but occasionally severe complication following HSCT and may require active treatment.

Evaluating new biomarkers for diabetic nephropathy: Role of α2-macroglobulin, podocalyxin, α-L-fucosidase, retinol-binding protein-4, and cystatin C.

BACKGROUND: The intricate relationship between type 2 diabetes mellitus (T2DM) and diabetic nephropathy (DN) presents a challenge in understanding the significance of various biomarkers in diagnosis. AIM: To elucidate the roles and diagnostic values of α2-macroglobulin (α2-MG), podocalyxin (PCX), α-L-fucosidase (AFU), retinol-binding protein-4 (RBP-4), and cystatin C (CysC) in DN. METHODS: From December 2018 to December 2020, 203 T2DM patients were enrolled in the study. Of these, 115 were diagnosed with DN (115 patients), while the remaining 88 patients were classified as non-DN. The urinary levels of α2-MG, PCX, and AFU and the serum concentrations RBP-4 and CysC were measured in conjunction with other relevant clinical indicators to evaluate their potential correlations and diagnostic utility. RESULTS: After adjustments for age and gender, significant positive correlations were observed between the biomarkers CysC, RBP-4, α2-MG/urinary creatinine (UCr), PCX/UCr, and AFU/UCr, and clinical indicators such as urinary albumin-to-creatinine ratio (UACR), serum creatinine, urea, 24-h total urine protein, and neutrophil-to-lymphocyte ratio (NLR). Conversely, these biomarkers exhibited negative correlations with the estimated glomerular filtration rate (P < 0.05). Receiver operating characteristic (ROC) curve analysis further demonstrated the diagnostic performance of these biomarkers, with UACR showcasing the highest area under the ROC curve (AUCROC) at 0.97. CONCLUSION: This study underscores the diagnostic significance of α2-MG, PCX, and AFU in the development of DN. The biomarkers RBP-4, CysC, PCX, AFU, and α2-MG provide promising diagnostic insights, while UACR is the most potent diagnostic biomarker in assessing DN.

The correlation between anti-phospholipase A2 receptor antibodies and hypercoagulability in patients with idiopathic membranous nephropathy.

BACKGROUND: Patients with idiopathic membranous nephropathy (IMN) are more likely to be complicated by venous thromboembolism (VTE). The aim of the study was to investigate the potential association between anti-phospholipase A2 receptor (PLA2R) antibodies and hypercoagulability in patients with IMN. METHODS: A total of 168 patients with biopsy-proven IMN and 36 patients with biopsy-proven minimal change disease (MCD) were enrolled in this study. The clinical data, serum anti-PLA2R antibodies and coagulation-related indices of the patients were retrospectively analyzed. RESULTS: Patients with IMN were categorized into glomerular PLA2R staining-positive (GAg+) IMN group and glomerular PLA2R staining-negative (GAg-) IMN group in the study. Patients with IMN who were GAg + had lower PT, APTT and R time than patients with IMN who were GAg-, while the CI value was higher in patients with IMN who were GAg+. Patients with IMN who were GAg + were divided into the SAb+/GAg + group and the SAb-/GAg + group. Patients with IMN who were SAb+/GAg + had higher Fib and MA values than patients with IMN who were SAb-/GAg+. Correlation analysis showed that serum anti-PLA2R antibodies were positively correlated with fibrinogen, D-dimer, K time, CI value, α-angle, and MA value. Multiple linear regression analysis indicated that anti-PLA2R antibodies were independently correlated with fibrinogen and MA value. CONCLUSION: Our study provides a new perspective on the underlying mechanisms of hypercoagulability in patients with IMN. Anti-PLA2R antibodies are associated with hypercoagulability in patients with IMN and may affect coagulation in patients with IMN by affecting platelet aggregation function and fibrinogen counts.

Protocol biopsy of kidney allograft enables early detection of BK virus nephropathy to preserve kidney allograft function.

BACKGROUND: The Banff Working Group has updated the histological classification of BK virus nephropathy (BKVN), highlighting the importance of early detection. However, an early detection strategy for BKVN using biopsy has not yet been established. Our investigation aimed to assess the efficacy of protocol biopsy for the diagnosis of BKVN. METHODS: We performed a retrospective cohort study of 314 patients who had undergone kidney transplantation between 2006 and 2021. Kidney allograft biopsies were performed as part of a protocol biopsy at 3 months and 1 year post-transplantation. Following the diagnosis of BKVN, the immunosuppressant dose was reduced. RESULTS: Twelve patients (3.8%) were diagnosed with BKVN by biopsy. Most diagnoses are established during the early stages of BKVN (polyomavirus nephropathy class 1 in six, class 2 in five, and class 3 in one). Following the reduction in immunosuppressant dose, kidney allograft function did not deteriorate in any patients. Additionally, test for BK virus DNA in the blood was negative. All but one patient demonstrated histological resolution of BKVN, and the other had a very slight positivity for the simian virus 40 large T antigen. The median follow-up time after BKVN diagnosis was 6 years. One patient developed de novo donor-specific antibody and subclinical acute antibody-mediated rejection that was successfully cured. CONCLUSIONS: Our analysis indicates that protocol biopsy may enable the early detection of BKVN, resulting in the preservation of kidney function.

The m6A-ncRNAs axis in diabetes complications: novel mechanism and therapeutic potential.

Diabetes, a multifaceted metabolic disorder, poses a significant global health burden with its increasing prevalence and associated complications, such as diabetic nephropathy, diabetic retinopathy, diabetic cardiomyopathy, and diabetic angiopathy. Recent studies have highlighted the intricate interplay between N6-methyladenosine (m6A) and non-coding RNAs (ncRNAs) in key pathways implicated in these diabetes complications, like cell apoptosis, oxidative stress, and inflammation. Thus, understanding the mechanistic insights into how m6A dysregulation impacts the expression and function of ncRNAs opens new avenues for therapeutic interventions targeting the m6A-ncRNAs axis in diabetes complications. This review explores the regulatory roles of m6A modifications and ncRNAs, and stresses the role of the m6A-ncRNA axis in diabetes complications, providing a therapeutic potential for these diseases.

The Association of Lower Levels of Baseline Proteinuria With Earlier Remission in Primary Membranous Nephropathy.

Aim To study the clinical profile and course and to assess the outcome of patients with biopsy-proven primary membranous nephropathy (MN). Methods This study was carried out in a tertiary care hospital between December 2017 and December 2021 on four-year retrospective biopsy-proven patients with membranous nephropathy (MN). Urinary proteins, serum albumin, and serum creatinine were the baseline investigations that were performed. Special tests were done whenever necessary. Patients were treated with a modified Ponticelli (MP) regimen whenever needed. Patients were followed up after treatment administration for a minimum of a year. Results The study was done in 48 biopsy-proven MN patients. Thirty-six patients had primary MN with a mean age of 47+/-11.7 years. The male-female ratio was 2.6:1. Hypertension was present in 39% (14 patients), microscopic hematuria in 28% (10 patients), and acute kidney injury in 22% (8 patients). The mean 24-hour urinary protein was 11.2+/-2.9 g/day. PLA2R was positive in 78% (28 patients) of primary MN patients. Spontaneous remission was noted in 13.8% (5 patients) who were treated conservatively. Spontaneous remission was associated with lower baseline proteinuria (p<0.001), higher baseline serum albumin (p<0.001), and PLA2R negativity (p=0.04). Complete or partial treatment response was noted in 74.2% (23 patients). Treatment remission was associated with lower baseline proteinuria (p=0.018). Secondary membranous nephropathy (secondary MN) was diagnosed in 12 patients. Eleven were class V lupus nephritis, all women, and one male person living with HIV/AIDS (PLHA). Conclusions The majority of our primary MN patients were PLA2R positive on renal biopsy. Statistically significant factors associated with spontaneous remission were lower proteinuria, higher serum albumin at baseline, and PLA2R negativity. Treatment response was associated with lower proteinuria at presentation. The most common cause of secondary MN was lupus nephritis.

The impact of mild and moderate COVID-19 infection on the progression of kidney dysfunction in patients with IgA nephropathy.

Background: Previous research indicates that coronavirus disease 2019 (COVID-19) infection may have a role in triggering immunoglobulin A (IgA) nephropathy. However, limited research has explored the clinical implications of COVID-19 infection in individuals already diagnosed with IgA nephropathy. This study aimed to determine whether COVID-19 infection independently affects the subsequent trajectory of kidney function in IgA nephropathy patients. Methods: This was a single-center cohort study. The study included 199 patients diagnosed with IgA nephropathy. The COVID-19 infection status was determined using a combined method: a questionnaire and the Health Code application, both administered at the end of 2022 in northern China. Kidney function trajectory was assessed by the estimated glomerular filtration rate (eGFR), calculated based on serum creatinine levels measured during follow-up outpatient visits. The primary endpoint of interest was the eGFR trajectory. Results: Out of the 199 participants, 75% (n = 181) reported a confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, determined through antigen or polymerase chain reaction tests, accounting for 79% (n = 143) of the infected patients. A significant majority (98%) experienced mild to moderate symptoms. Over a median follow-up period of 10.7 months post-COVID-19 infection, notable clinical events included gross hematuria in 30 patients (16.6%), which normalized within an average of 3 days. Additionally, a 2-fold increase in proteinuria or progression to the nephrotic range was observed in 10 individuals (5.5%). No cases of acute kidney injury were noted. COVID-19 exposure was associated with an absolute change in eGFR of 2.98 mL/min/1.73 m2 per month (95% confidence interval 0.46 to 5.50). However, in a fully adjusted model, the estimated changes in eGFR slope post-COVID-19 were -0.39 mL/min/1.73 m2 per month (95% confidence interval -0.83 to 0.06, P = .088) which included the possibility of no significant effect. Notably, a higher rate of kidney function decline was primarily observed in patients with a baseline eGFR <45 mL/min/1.73 m2 [-0.56 mL/min/1.73 m2 (-1.11 to -0.01), P = .048]. In the cohort, there were few instances of severe COVID-19 cases. The absence of long-term follow-up outcomes was observed. Conclusions: Overall, mild to moderate COVID-19 infection does not appear to significantly exacerbate the subsequent decline in kidney function among IgA nephropathy patients, particularly in those with preserved baseline kidney function.

Cathepsin S (CTSS) in IgA nephropathy: an exploratory study on its role as a potential diagnostic biomarker and therapeutic target.

Introduction: IgA nephropathy (IgAN), a prevalent form of glomerulonephritis globally, exhibits complex pathogenesis. Cathepsins, cysteine proteases within lysosomes, are implicated in various physiological and pathological processes, including renal conditions. Prior observational studies have suggested a potential link between cathepsins and IgAN, yet the precise causal relationship remains unclear. Methods: We conducted a comprehensive bidirectional and multivariable Mendelian randomization (MR) study using publicly available genetic data to explore the causal association between cathepsins and IgAN systematically. Additionally, immunohistochemical (IHC) staining and enzyme-linked immunosorbent assay (ELISA) were employed to evaluate cathepsin expression levels in renal tissues and serum of IgAN patients. We investigated the underlying mechanisms via gene set variation analysis (GSVA), gene set enrichment analysis (GSEA), and immune cell infiltration analysis. Molecular docking and virtual screening were also performed to identify potential drug candidates through drug repositioning. Results: Univariate MR analyses demonstrated a significant link between increased cathepsin S (CTSS) levels and a heightened risk of IgAN. This was evidenced by an odds ratio (OR) of 1.041 (95% CI=1.009-1.073, P=0.012) as estimated using the inverse variance weighting (IVW) method. In multivariable MR analysis, even after adjusting for other cathepsins, elevated CTSS levels continued to show a strong correlation with an increased risk of IgAN (IVW P=0.020, OR=1.037, 95% CI=1.006-1.069). However, reverse MR analyses did not establish a causal relationship between IgAN and various cathepsins. IHC and ELISA findings revealed significant overexpression of CTSS in both renal tissues and serum of IgAN patients compared to controls, and this high expression was unique to IgAN compared with several other primary kidney diseases such as membranous nephropathy, minimal change disease and focal segmental glomerulosclerosis. Investigations into immune cell infiltration, GSEA, and GSVA highlighted the role of CTSS expression in the immune dysregulation observed in IgAN. Molecular docking and virtual screening pinpointed Camostat mesylate, c-Kit-IN-1, and Mocetinostat as the top drug candidates for targeting CTSS. Conclusion: Elevated CTSS levels are associated with an increased risk of IgAN, and this enzyme is notably overexpressed in IgAN patients' serum and renal tissues. CTSS could potentially act as a diagnostic biomarker, providing new avenues for diagnosing and treating IgAN.

Tonabersat suppresses priming/activation of the NOD-like receptor protein-3 (NLRP3) inflammasome and decreases renal tubular epithelial-to-macrophage crosstalk in a model of diabetic kidney disease.

BACKGROUND: Accompanied by activation of the NOD-like receptor protein 3 (NLRP3) inflammasome, aberrant connexin 43 (Cx43) hemichannel-mediated ATP release is situated upstream of inflammasome assembly and inflammation and contributes to multiple secondary complications of diabetes and associated cardiometabolic comorbidities. Evidence suggests there may be a link between Cx43 hemichannel activity and inflammation in the diabetic kidney. The consequences of blocking tubular Cx43 hemichannel-mediated ATP release in priming/activation of the NLRP3 inflammasome in a model of diabetic kidney disease (DKD) was investigated. We examined downstream markers of inflammation and the proinflammatory and chemoattractant role of the tubular secretome on macrophage recruitment and activation. METHODS: Analysis of human transcriptomic data from the Nephroseq repository correlated gene expression to renal function in DKD. Primary human renal proximal tubule epithelial cells (RPTECs) and monocyte-derived macrophages (MDMs) were cultured in high glucose and inflammatory cytokines as a model of DKD to assess Cx43 hemichannel activity, NLRP3 inflammasome activation and epithelial-to-macrophage paracrine-mediated crosstalk. Tonabersat assessed a role for Cx43 hemichannels. RESULTS: Transcriptomic analysis from renal biopsies of patients with DKD showed that increased Cx43 and NLRP3 expression correlated with declining glomerular filtration rate (GFR) and increased proteinuria. In vitro, Tonabersat blocked glucose/cytokine-dependant increases in Cx43 hemichannel-mediated ATP release and reduced expression of inflammatory markers and NLRP3 inflammasome activation in RPTECs. We observed a reciprocal relationship in which NLRP3 activity exacerbated increased Cx43 expression and hemichannel-mediated ATP release, events driven by nuclear factor kappa-B (NFκB)-mediated priming and Cx43 hemichannel opening, changes blocked by Tonabersat. Conditioned media (CM) from RPTECs treated with high glucose/cytokines increased expression of inflammatory markers in MDMs, an effect reduced when macrophages were pre-treated with Tonabersat. Co-culture using conditioned media from Tonabersat-treated RPTECs dampened macrophage inflammatory marker expression and reduced macrophage migration. CONCLUSION: Using a model of DKD, we report for the first time that high glucose and inflammatory cytokines trigger aberrant Cx43 hemichannel activity, events that instigate NLRP3-induced inflammation in RPTECs and epithelial-to-macrophage crosstalk. Recapitulating observations previously reported in diabetic retinopathy, these data suggest that Cx43 hemichannel blockers (i.e., Tonabersat) may dampen multi-system damage observed in secondary complications of diabetes.

HNRNP I promotes IRAK1 degradation to reduce podocyte apoptosis and inflammatory response alleviating renal injury in diabetic nephropathy.

Podocytes maintain renal filtration integrity when the glomerular filtration barrier (GFB) is integrated. Impairment or attrition of podocytes, leading to compromised GFB permeability, constitutes the primary etiology of proteinuria and is a hallmark pathological feature of diabetic nephropathy (DN). This study centers on Heterogeneous Nuclear Ribonucleoprotein I (HNRNP I), an RNA-binding protein, delineating its role in facilitating DN-induced renal damage by modulating podocyte health. Comparative analyses in renal biopsy specimens from DN patients and high-glucose-challenged podocyte models in vitro revealed a marked downregulation of HNRNP I expression relative to normal renal tissues and podocytes. In vitro assays demonstrated that high-glucose conditions precipitated a significant reduction in podocyte viability and an escalation in markers indicative of apoptosis. Conversely, HNRNP I overexpression was found to restore podocyte viability and attenuate apoptotic indices. IRAK1, a gene encoding a protein integral to inflammatory signaling, was shown to interact with HNRNP I, which promotes IRAK1 degradation. This interaction culminates in suppressing the PI3K/AKT/mTOR signaling pathway, thereby diminishing podocyte apoptosis and mitigating renal damage in DN. This investigation unveils the mechanistic role of HNRNP I in DN for the first time, potentially informing novel therapeutic strategies for DN renal impairment.

Exosomes derived from umbilical cord-derived mesenchymal stem cells exposed to diabetic microenvironment enhance M2 macrophage polarization and protect against diabetic nephropathy.

The role of mesenchymal-stem-cell-derived exosomes (MSCs-Exo) in the regulation of macrophage polarization has been recognized in several diseases. There is emerging evidence that MSCs-Exo partially prevent the progression of diabetic nephropathy (DN). This study aimed to investigate whether exosomes secreted by MSCs pre-treated with a diabetic environment (Exo-pre) have a more pronounced protective effect against DN by regulating the balance of macrophages. Exo-pre and Exo-Con were isolated from the culture medium of UC-MSCs pre-treated with a diabetic mimic environment and natural UC-MSCs, respectively. Exo-pre and Exo-Con were injected into the tail veins of db/db mice three times a week for 6 weeks. Serum creatinine and serum urea nitrogen levels, the urinary protein/creatinine ratio, and histological staining were used to determine renal function and morphology. Macrophage phenotypes were analyzed by immunofluorescence, western blotting, and quantitative reverse transcription polymerase chain reaction. In vitro, lipopolysaccharide-induced M1 macrophages were incubated separately with Exo-Con and Exo-pre. We performed microRNA (miRNA) sequencing to identify candidate miRNAs and predict their target genes. An miRNA inhibitor was used to confirm the role of miRNAs in macrophage modulation. Exo-pre were more potent than Exo-Con at alleviating DN. Exo-pre administration significantly reduced the number of M1 macrophages and increased the number of M2 macrophages in the kidney compared to Exo-Con administration. Parallel outcomes were observed in the co-culture experiments. Moreover, miR-486-5p was distinctly expressed in Exo-Con and Exo-pre groups, and it played an important role in macrophage polarization by targeting PIK3R1 through the PI3K/Akt pathway. Reducing miR-486-5p levels in Exo-pre abolished macrophage polarization modulation. Exo-pre administration exhibited a superior effect on DN by remodeling the macrophage balance by shuttling miR-486-5p, which targets PIK3R1.

BK polyomavirus infection: more than 50 years and still a threat to kidney transplant recipients.

BK polyomavirus (BKPyV) is a ubiquitous human polyomavirus and a major infection after kidney transplantation, primarily due to immunosuppression. BKPyV reactivation can manifest as viruria in 30%-40%, viremia in 10%-20%, and BK polyomavirus-associated nephropathy (BKPyVAN) in 1%-10% of recipients. BKPyVAN is an important cause of kidney graft failure. Although the first case of BKPyV was identified in 1971, progress in its management has been limited. Specifically, there is no safe and effective antiviral agent or vaccine to treat or prevent the infection. Even in the current era, the mainstay approach to BKPyV is a reduction in immunosuppression, which is also limited by safety (risk of de novo donor specific antibody and rejection) and efficacy (graft failure). However, recently BKPyV has been getting more attention in the field, and some new treatment strategies including the utilization of viral-specific T-cell therapy are emerging. Given all these challenges, the primary focus of this article is complications associated with BKPyV, as well as strategies to mitigate negative outcomes.

Anisodamine for the prevention of contrast-induced nephropathy in patients with acute coronary syndrome: a pilot systematic review and meta-analysis of randomized controlled trials.

Introduction: Contrast-induced nephropathy (CIN) is a common post-procedural complication of percutaneous coronary intervention for acute myocardial infarction (AMI). Anisodamine hydrobromide is an alkaloid that has demonstrated efficacy in improving microcirculation. This meta-analysis aims to evaluate the reno-protective effects of Anisodamine in patients undergoing percutaneous coronary intervention (PCI) for AMI. Methods: PubMed, Embase, Cochrane Library, Scopus, and clinicaltrials.gov were searched from inception to January 2024 for randomized controlled trials (RCTs) comparing the efficacy of Anisodamine in preventing the development of CIN. Outcomes of interest included the incidence of CIN, serum creatinine levels, and estimated glomerular filtration rate (eGFR). A random-effects model was used for pooling standard mean differences (SMDs) and odds ratios (ORs) with a 95% CI. Statistical significance was considered at a P less than 0.05. Results: Three RCTs involving 563 patients were included. Anisodamine was associated with a reduction in the incidence of CIN [OR: 0.44; 95% CI: 0.28, 0.69; P=0.0003], a reduction in serum creatinine levels at 48 [SMD: -6.78; 95% CI: -10.54,-3.02; P=0.0004] and 72 h [SMD: -6.74; 95% CI: -13.33,-0.15; P=0.03], and a higher eGFR at 24 [SMD: 5.77; 95% CI: 0.39, 11.14; P=0.03], and 48 h [SMD: 4.70; 95% CI: 2.03,7.38; P=0.0006]. The levels of serum creatinine at 24 h and eGFR value at 72 h were comparable between both groups. Conclusions: Anisodamine has demonstrated clinical efficacy in ameliorating the development of CIN post-PCI in AMI patients. Large, multi-centric RCTs are warranted to evaluate the robustness of these findings.

Clinicopathological phenotype and outcomes of NCAM-1+ membranous lupus nephritis.

INTRODUCTION: No studies explored the long-term outcomes of neural cell adhesion molecule 1 (NCAM1) associated membranous lupus nephritis (MLN) patients. METHOD: We performed immunohistochemical studies on kidney biopsy specimens against NCAM1 in consecutive MLN patients. The clinical and histopathological characteristics and outcomes of cases of NCAM1 associated MLN patients are described and compared with NCAM1 negative patients. In addition, we detected serum circulating anti-NCAM1 antibodies through western blotting and indirect immunofluorescence assays. RESULTS: Among 361 MLN cases, 18 (5.0%) were glomerular NCAM1-positive. NCAM1 positive MLN patients were older [35 years (IQR 27-43) versus 28 (22-37); P = 0.050) and had lower systemic lupus erythematosus disease activity index [11 (IQR 8-12) versus 14 (10-18); P = 0.007], serum creatinine [60 µmol/L (IQR 50-70) versus 70 (54-114); P = 0.029], activity index [3 (IQR 2-6) versus 6 (3-9); P = 0.045] at kidney biopsy compared with NCAM1 negative patients. The percentage of positive anti-Sjogren's syndrome related antigen A antibodies in NCAM1 positive patients was significantly greater (83.3% versus 58.2%; P = 0.035) than in the NCAM1 negative patients. However, no evidence of neuropsychiatric disorders was found in these 18 patients. There were no significant differences in the treatment response and the risk of end stage renal diseases between NCAM1 positive and negative groups (P = 0.668 and P = 0.318, respectively). But the risk of death was much higher in the NCAM1 positive group than the NCAM1 negative group (27.8% vs. 8.1%, P = 0.007). Moreover, the risk of death was also much higher in the NCAM1 positive group than the matched NCAM1 negative group (Log-rank P = 0.013). Additionally, circulating anti-NCAM1 antibodies can be detected in 1/5 (20%) patients who had serum available. CONCLUSION: The prevalence of NCAM1 positivity was 5.0% in our cohort of MLN and the high mortality in these subgroup patients are needed to validate in future studies.

Fanconi syndrome with karyomegalic interstitial nephritis after ifosfamide treatment for osteosarcoma: a case report.

Patients with ifosfamide-induced renal damage present with Fanconi syndrome. Karyomegalic nephropathy/interstitial nephritis (KNIN) is a rare form of chronic tubulo-interstitial nephritis that was initially considered a type of familial nephropathy. However, several reports of drug-induced KNIN, i.e., KNIN-like nephropathy, have been reported in recent years. We present the case of an 18-year-old man who presented with Fanconi syndrome and progressive renal dysfunction after receiving chemotherapy including ifosfamide and cisplatin for right femoral osteosarcoma. Renal biopsy revealed numerous atrophied tubular epithelial cells with large, polymorphic nuclei, and the definitive diagnosis was KNIN. Most patients with KNIN-like nephropathy who receive ifosfamide are concomitantly treated with cisplatin, indicating that ifosfamide and cisplatin might act synergistically to increase the risk for KNIN-like nephropathy. Further investigation in case series is warranted to reveal potential treatment approaches and to evaluate prognosis.

Membranous nephropathy: pathogenesis and treatments.

Membranous nephropathy (MN), an autoimmune disease, can manifest at any age and is among the most common causes of nephrotic syndrome in adults. In 80% of cases, the specific etiology of MN remains unknown, while the remaining cases are linked to drug use or underlying conditions like systemic lupus erythematosus, hepatitis B virus, or malignancy. Although about one-third of patients may achieve spontaneous complete or partial remission with conservative management, another third face an elevated risk of disease progression, potentially leading to end-stage renal disease within 10 years. The identification of phospholipase A2 receptor as the primary target antigen in MN has brought about a significant shift in disease management and monitoring. This review explores recent advancements in the pathophysiology of MN, encompassing pathogenesis, clinical presentations, diagnostic criteria, treatment options, and prognosis, with a focus on emerging developments in pathogenesis and therapeutic strategies aimed at halting disease progression. By synthesizing the latest research findings and clinical insights, this review seeks to contribute to the ongoing efforts to enhance our understanding and management of this challenging autoimmune disorder.

A case of membranous nephropathy complicated by Cronkhite-Canada syndrome successfully treated with mizoribine.

Cronkhite-Canada syndrome (CCS) is a non-hereditary disorder characterized by non-neoplastic hamartomatous gastrointestinal polyposis, hair loss, nail atrophy, hyperpigmentation, and diarrhea. While the relationship between CCS and nephritis remains unclear, seven cases of nephritis complicated by CCS have been reported to date, all of which were membranous nephropathy (MN). A 57-year-old man presented with taste disturbance, hair loss, nail plate atrophy, skin pigmentation, and frequent diarrhea. Endoscopic findings showed multiple polyposis of the stomach and large intestine. Given the above, he was diagnosed with CCS. The symptoms gradually improved with prednisolone treatment, although urinary protein and hypoproteinemia appeared during the tapering of prednisolone. He was diagnosed with MN using a renal biopsy, and immunofluorescence microscopy with IgG subclass staining showed predominantly diffuse granular capillary wall staining of IgG4. The cause of secondary MN was not found, including malignant tumors. Nephrotic-range proteinuria persisted despite treatment with prednisolone and cyclosporine. Additional treatment with mizoribine resulted in incomplete remission type 1 of nephrotic syndrome, suggesting that mizoribine may be a treatment option for patients with CCS with steroid-resistant MN. Considering a high prevalence of hypoproteinemia due to chronic diarrhea and protein-losing enteropathy in patients with CCS, proteinuria might be overlooked; thus, follow-up urinalysis would be recommended in patients with CCS.

Preclinical antidiabetic and antioxidant effects of Erythrophleum africanum (benth.) harms in streptozotocin-induced diabetic nephropathy.

OBJECTIVES: This study investigated the antidiabetic effects of the methanolic extract of E. africanum (MEEA) stem bark on streptozotocin (STZ)-induced diabetic nephropathy (DN) in Wistar rats. METHODS: The in vitro enzyme (α-amylase) inhibitory activity of MEEA was measured using a standard procedure. Diabetic rats with fasting blood glucose above 250 mg/dL were considered diabetic and were divided into the following groups: control (distilled water-treated), diabetic-control, diabetic metformin (100 mg/kg), diabetes + MEEA (150 mg/kg), and diabetes + MEEA (300 mg/kg) via oral gavage once daily for 14 days. At the end of the experimental period, kidney tissues were collected for biochemical and histological analyses. Kidney apoptosis and marker gene expression were measured by real-time quantitative PCR. RESULTS: MEEA exhibited α-amylase inhibitory effects. MEEA significantly (p<0.05) reduced the STZ-induced increases in blood glucose, serum urea, serum creatinine, uric acid, alanine aminotransferase, alkaline phosphatase, and malondialdehyde and increased the STZ-induced decreases in superoxide dismutase, catalase, and reduced glutathione. In addition, MEEA protects against DN by significantly downregulating the mRNA expression of cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), cAMP-response binding protein (CREB), and cFOS and upregulating B-cell lymphoma 2 (Bcl-2), suggesting that the nephroprotective ability of MEEA is due to the modulation of the cAMP/PKA/CREB/cFOS signaling pathway. Furthermore, MEEA treatment protected against histopathological alterations observed in diabetic rats. CONCLUSIONS: The data from this study suggest that MEEA modulates glucose homeostasis and inhibits redox imbalance in DN rats.

Antibrush Border Antibody Disease: A Case Series.

Antibrush border antibody (ABBA) disease is a rare cause of kidney disease characterized by progressive renal tubular injury associated with immune complex deposition along the basement membranes of the proximal tubule and circulating autoantibodies to brush border antigens. Several antigens have been identified as targets of autoantibodies in this disease, including low-density lipoprotein receptor related protein 2 (LRP2), cubilin, and amnionless proteins. We present 9 patients from 2 academic medical centers and describe the clinicopathologic characteristics and outcome data. All patients presented with acute kidney injury and proteinuria. Pathology confirmed immune complex deposition along proximal tubular basement membranes in all patients, but the majority (6/8) also showed segmental glomerular subepithelial immune complexes. Two of 3 patients treated with rituximab demonstrated stabilization of kidney function; 1 of these patients had mantle cell lymphoma. One patient with lung cancer showed stabilization of disease after treatment of the malignancy. The remaining patients progressed to end-stage kidney disease with either conservative therapy (3 patients) or immunosuppression with glucocorticoids (2 patients). This series highlights the poor prognosis of ABBA disease, but a potential benefit of anti-B cell therapy or treatment of an underlying malignancy in some cases.