Gengru Jiang

Background: Focal segmental glomerulosclerosis (FSGS) is an increasingly prevalent group of refractory glomerular diseases and a significant aetiology of end-stage renal disease. Podocyte injury and depletion significantly contribute to the pathogenesis and progression of FSGS. MicroRNAs (miRNAs) are noncoding RNAs that regulate the expression of specific genes in relevant cells, thereby playing crucial roles in the pathogenesis of FSGS. Many studies have shown that miRNAs can be secreted from cells into body fluids and that these miRNAs in the circulation are highly stable. The gold standard for FSGS diagnosis is kidney biopsy; however, the clinical heterogeneity of FSGS, along with variations in histology and nonspecific morphological features, can impact its diagnostic accuracy. Thus, the discovery of novel and efficacious biomarkers is crucial in facilitating the diagnosis of FSGS. In addition, the degree of kidney damage in patients with FSGS varies at different stages, necessitating individualized diagnosis and treatment approaches. Considering the side effects of glucocorticoids, determining whether a patient is steroid resistant is vital. Thus, ideal biomarkers should not only be specific and sensitive but also have the ability to accurately reflect the stage or prognosis of the disease to improve the treatment for patients. Summary: To date, numerous studies have shown that both urinary miRNAs and plasma miRNAs are potential biomarkers for FSGS. In addition, the identification of miRNA biomarkers specific for the FSGS disease state may provide new insights into the underlying pathological mechanism of FSGS. Key Messages: Here we summarize the currently available miRNA biomarkers that could help us better understand the diagnosis, disease activity, prognosis, and clinical features of FSGS.

To investigate the potential mechanisms of fatty acid metabolism (FAM)-related genes in IgA nephropathy (IgAN) and to explore its immune cell infiltration characteristic. Datasets for IgAN and FAM-related genes were obtained from GEO and MSigDB database, respectively. We employed differential expression analysis and WGCNA to identify common genes. GO and KEGG analyses were performed to compare the differences between IgAN and control groups. Furthermore, LASSO logistic regression was applied to develop a predictive model based on FAM-related genes. The efficacy of this prognostic model was evaluated using ROC analysis. The infiltration of immune cells and immune-related functions were assessed with CIBERSORT tool. Finally, the identified key genes were validated in blood samples from IgAN and control patients, as well as in human mesangial cells (HMCs) following Gd-IgA stimulation using Real-time PCR. A total of 12 hub genes linked to FAM were identified in patients with IgAN. A predictive model consisting of four genes was conducted through COX and LASSO regression analysis, revealing AUC values that indicate a relatively strong diagnostic capability. Immune infiltration analysis indicated that various immune cells have significant associations with IgAN. Additionally, Real-time PCR assays confirmed that the expression levels of hub genes were markedly reduced in IgAN patients and in Gd-IgA treated HMCs compared to controls. This study employed bioinformatics methods to unveiled the immune cell infiltration associated with IgAN and to explore the potential genetic connection between FAM and IgAN. This could aid in predicting the risk of IgAN and enhance both diagnosis and prognosis of this condition.

Introduction: Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication associated with increased morbidity and mortality. Tissue inhibitor metalloproteinases-2 • insulin-like growth factor-binding protein 7 (TIMP-2•IGFBP7) determines tubular stress markers, which may occur prior to tubular damage. Previous studies on the use of TIMP-2•IGFBP7 for the prediction of CSA-AKI showed divergent results. Therefore, this study aimed to explore the predictive value of TIMP-2•IGFBP7 measurements for the early detection of acute kidney injury (AKI) and short-term adverse outcomes after cardiac surgery. Methods: In the prospective cohort study, blood and urine samples were collected 6–12 h after cardiac surgery. Blood samples to monitor serum creatinine levels were additionally extracted from days 1 to 7. AKI was defined based on the KDIGO consensus guidelines. AKI within 7 days following surgery was the primary outcome. The initiation of renal replacement therapy, in intensive care unit mortality, and the combination of both were secondary outcomes. Results: A total of 557 patients were enrolled, 134 (24.06%) of them developed AKI and 33 (5.9%) had moderate or severe AKI. AKI developed more frequently in elderly patients with diabetes or with higher baseline serum creatinine levels. Patients with AKI had higher EuroSCORE II, Cleveland clinical score, and simplified renal index than those without AKI. Urinary TIMP-2•IGFBP7 was significantly higher in patients with AKI. The area under the curve was 0.66 in predicting all AKI and 0.70 in predicting stages 2 and 3 AKI. The resulting sensitivity and specificity were 44.0% and 83.9%, respectively, for a calculated threshold TIMP-2•IGFBP7 value of 0.265 (ng/ml)2/1,000. The TIMP-2•IGFBP7 values, simplified renal index (SRI) Score and age were significantly associated with AKI within 7 days postoperatively. A total of 33 patients reached the composite endpoint, the percentage of patients who reached the composite end-point in the TIMP-2•IGFBP7 of >0.265 (ng/ml)2/1,000 group was significantly higher than that of ≤0.265 (ng/ml)2/1,000 group. Conclusions: Postoperative implementation of TIMP-2•IGFBP7 improved prediction of CSA-AKI and may aid in identifying patients at risk of short-term adverse outcomes. We identified an ideal calculated cutoff value of 0.265 (ng/ml))2/1,000 for the prediction of CSA-AKI among all AKI patients.

Background: Nephrotic syndrome that is resistant to steroid therapy is termed refractory nephrotic syndrome (RNS), a condition that is associated with an increased risk of end-stage renal disease. Immunosuppressants are used to treat RNS; however, prolonged use may lead to significant adverse effects. Mizoribine (MZR) is a novel agent used in long-term immunosuppressive therapy, which has few adverse effects, but data on its long-term use in patients with RNS are unavailable. Objective: We propose a trial to examine the efficacy and safety of MZR compared with cyclophosphamide (CYC) in Chinese adult patients with RNS. Methods: This is a multicenter, randomized, controlled interventional study with a screening phase (1 week) and a treatment phase (52 weeks). This study has been reviewed and approved by the Medical Ethics Committees of all 34 medical centers that are participating. Patients with RNS consent to participation, and are enrolled and randomized to an MZR group or a CYC group (1:1 ratio), with each group receiving tapering doses of oral corticosteroids. Participants are assessed for adverse effects, and laboratory results are collected at 8 visits during the treatment phase (weeks 4, 8, 12, 16, 20, 32, 44, and 52 [exit visit]). Participants are able to withdraw voluntarily, and investigators are required to remove patients when there are safety concerns or deviations from the protocol. Results: The study started in November 2014 and was completed in March 2019. A total of 239 participants from 34 hospitals in China have been enrolled. Data analysis has been completed. The results are being finalized by the Center for Drug Evaluation. Conclusions: This study examines the safety and efficacy of MZR as a long-term treatment approach for Chinese adults with RNS. It is the longest lasting and largest randomized controlled trial to examine MZR in Chinese patients. The results can help determine whether RNS should be considered as an additional indication for MZR treatment in China. Trial Registration: ClinicalTrials.gov NCT02257697; https://clinicaltrials.gov/ct2/show/NCT02257697 International Registered Report Identifier (IRRID): RR1-10.2196/46101

Significance Statement: Causes of congenital anomalies of the kidney and urinary tract (CAKUT) remain unclear. The authors investigated whether and how inactivation of Ash2l—which encodes a subunit of the COMPASS methyltransferase responsible for genome-wide histone H3 lysine K4 (H3K4) methylation—might contribute to CAKUT. In a mouse model, inactivation of Ash2l in the ureteric bud (UB) lineage led to CAKUT-like phenotypes. Removal of ASH2L led to deficient H3K4 trimethylation, which slowed cell proliferation at the UB tip, delaying budding and impairing branching morphogenesis. The absence of ASH2L also downregulated the expression of Ret, Gfra1, and Wnt11 genes involved in RET/GFRA1 signaling. These findings identify ASH2L-mediated H3K4 methylation as an upstream epigenetic regulator of signaling crucial for UB morphogenesis and indicate that deficiency or dysregulation of these processes may lead to CAKUT. Background: Ureteric bud (UB) induction and branching morphogenesis are fundamental to the establishment of the renal architecture and are key determinants of nephron number. Defective UB morphogenesis could give rise to a spectrum of malformations associated with congenital anomalies of the kidney and urinary tract (CAKUT). Signaling involving glial cell line–derived neurotrophic factor and its receptor rearranged during transfection (RET) and coreceptor GFRA1 seems to be particularly important in UB development. Recent epigenome profiling studies have uncovered dynamic changes of histone H3 lysine K4 (H3K4) methylation during metanephros development, and dysregulated H3K4 methylation has been associated with a syndromic human CAKUT. Methods: To investigate whether and how inactivation of Ash2l, which encodes a subunit of the COMPASS methyltransferase responsible for genome-wide H3K4 methylation, might contribute to CAKUT, we inactivated Ash2l specifically from the UB lineage in C57BL/6 mice and examined the effects on genome-wide H3K4 methylation and metanephros development. Genes and epigenome changes potentially involved in these effects were screened using RNA-seq combined with Cleavage Under Targets and Tagmentation sequencing. Results: UB-specific inactivation of Ash2l caused CAKUT-like phenotypes mainly involving renal dysplasia at birth, which were associated with deficient H3K4 trimethylation. Ash2l inactivation slowed proliferation of cells at the UB tip, delaying budding and impairing UB branching morphogenesis. These effects were associated with downregulation of Ret, Gfra1, and Wnt11, which participate in RET/GFRA1 signaling. Conclusions: These experiments identify ASH2L-dependent H3K4 methylation in the UB lineage as an upstream epigenetic regulator of RET/GFRA1 signaling in UB morphogenesis, which, if deficient, may lead to CAKUT.

BACKGROUND Nephrotic syndrome that is resistant to steroid therapy is termed refractory nephrotic syndrome (RNS), a condition that is associated with an increased risk of end-stage renal disease. Immunosuppressants are used to treat RNS; however, prolonged use may lead to significant adverse effects. Mizoribine (MZR) is a novel agent used in long-term immunosuppressive therapy, which has few adverse effects, but data on its long-term use in patients with RNS are unavailable. OBJECTIVE We propose a trial to examine the efficacy and safety of MZR compared with cyclophosphamide (CYC) in Chinese adult patients with RNS. METHODS This is a multicenter, randomized, controlled interventional study with a screening phase (1 week) and a treatment phase (52 weeks). This study has been reviewed and approved by the Medical Ethics Committees of all 34 medical centers that are participating. Patients with RNS consent to participation, and are enrolled and randomized to an MZR group or a CYC group (1:1 ratio), with each group receiving tapering doses of oral corticosteroids. Participants are assessed for adverse effects, and laboratory results are collected at 8 visits during the treatment phase (weeks 4, 8, 12, 16, 20, 32, 44, and 52 [exit visit]). Participants are able to withdraw voluntarily, and investigators are required to remove patients when there are safety concerns or deviations from the protocol. RESULTS The study started in November 2014 and was completed in March 2019. A total of 239 participants from 34 hospitals in China have been enrolled. Data analysis has been completed. The results are being finalized by the Center for Drug Evaluation. CONCLUSIONS This study examines the safety and efficacy of MZR as a long-term treatment approach for Chinese adults with RNS. It is the longest lasting and largest randomized controlled trial to examine MZR in Chinese patients. The results can help determine whether RNS should be considered as an additional indication for MZR treatment in China. CLINICALTRIAL ClinicalTrials.gov NCT02257697; https://clinicaltrials.gov/ct2/show/NCT02257697 INTERNATIONAL REGISTERED REPORT RR1-10.2196/46101

The accumulation of protein-bound uremic toxins and medium-large molecule toxins in maintenance hemodialysis (MHD) patients is one of the causes of long-term dialysis-related complications. Hemoperfusion can remove these uremic toxins and reduce the complications of MHD patients. Upon a review of the Chinese and international literature, combined with practical experience of clinical diagnosis and treatment, the Shanghai Medical Association Society of Nephrology reached a consensus on the clinical applications of hemoperfusion in MHD patients. This consensus included four aspects: selection of appropriate patients, treatment frequency, treatment methods, and adverse reactions and precautions and provided guidelines for the rational and standardized treatment of hemoperfusion in MHD patients.

Background and aims: Long-term peritoneal dialysis (PD) causes intestinal dysfunction, including constipation, diarrhea, or enteric peritonitis. However, the etiology and pathogenesis of these complications are still unclear and there are no specific drugs available in the clinic. This study aims to determine whether Astragaloside IV (AS IV) has therapeutic value on PD-induced intestinal epithelial barrier dysfunction in vivo and in vitro.Methods: We established two different long-term PD treatment mice models by intraperitoneally injecting 4.25% dextrose-containing peritoneal dialysis fluid (PDF) in uremia mice and normal mice, which were served as controls. In addition, PDF was applied to T84 cells in vitro. The therapeutic effects of AS IV on PD-induced intestinal dysfunction were then examined by histopathological staining, transmission electron microscopy, western blotting, and reverse transcription polymerase chain reaction. The protein levels of protein kinase B (AKT), glycogen synthase kinase 3β (GSK-3β) and β-catenin were examined after administration of AS IV.Results: In the present study, AS IV maintained the intestinal crypt, microvilli and desmosome structures in an orderly arrangement and improved intestinal epithelial permeability with the up-regulation of tight junction proteins in vivo. Furthermore, AS IV protected T84 cells from PD-induced damage by improving cell viability, promoting wound healing, and increasing the expression of tight junction proteins. Additionally, AS IV treatment significantly increased the levels of phosphorylation of AKT, inhibited the activity GSK-3β, and ultimately resulted in the nuclear translocation and accumulation of β-catenin.Conclusion: These findings provide novel insight into the AS IV-mediated protection of the intestinal epithelial barrier from damage via the AKT-GSK3β-β-catenin signal axis during peritoneal dialysis.