Comprehensive Analysis of PKD1 and PKD2 by Long-Read Sequencing in Autosomal Dominant Polycystic Kidney Disease.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is mainly caused by heterogeneous variants in the PKD1 and PKD2 genes. Genetic analysis of PKD1 has been challenging due to homology with 6 PKD1 pseudogenes and high GC content. METHODS: A single-tube multiplex long-range-PCR and long-read sequencing-based assay termed "comprehensive analysis of ADPKD" (CAPKD) was developed and evaluated in 170 unrelated patients by comparing to control methods including next-generation sequencing (NGS) and multiplex ligation-dependent probe amplification. RESULTS: CAPKD achieved highly specific analysis of PKD1 with a residual noise ratio of 0.05% for the 6 pseudogenes combined. CAPKD identified PKD1 and PKD2 variants (ranging from variants of uncertain significance to pathogenic) in 160 out of the 170 patients, including 151 single-nucleotide variants (SNVs) and insertion-deletion variants (indels), 6 large deletions, and one large duplication. Compared to NGS, CAPKD additionally identified 2 PKD1 variants (c.78_96dup and c.10729_10732dup). Overall, CAPKD increased the rate of variant detection from 92.9% (158/170) to 94.1% (160/170), and the rate of diagnosis with pathogenic or likely pathogenic variants from 82.4% (140/170) to 83.5% (142/170). CAPKD also directly determined the cis-/trans-configurations in 11 samples with 2 or 3 SNVs/indels, and the breakpoints of 6 large deletions and one large duplication, including 2 breakpoints in the intron 21 AG-repeat of PKD1, which could only be correctly characterized by aligning to T2T-CHM13. CONCLUSIONS: CAPKD represents a comprehensive and specific assay toward full characterization of PKD1 and PKD2 variants, and improves the genetic diagnosis for ADPKD.

Inflammation Is More Sensitive than Cell Proliferation in Response to Rapamycin Treatment in Polycystic Kidney Disease.

INTRODUCTION: It has been reported that rapamycin inhibited inflammation in renal interstitial diseases. We therefore hypothesized that rapamycin could attenuate inflammation in polycystic kidney disease (PKD). METHODS: Han:SPRD rats were treated with rapamycin by daily gavage from 4 weeks to 12 weeks of age at the dosage of 0.5 mg/kg/day (low dose) or 1 mg/kg/day (high dose). WT9-12 human PKD cells were treated with various concentrations of rapamycin. RESULTS: Two-kidney/total body weight ratio and cystic index in Cy/+ kidneys were significantly reduced with the treatment of low-dose rapamycin and further reduced by the treatment with high-dose rapamycin. However, the renal function of Cy/+ rats was equally improved by the treatment with either low-dose or high-dose rapamycin. The renal cell proliferation was significantly decreased in Cy/+ kidneys with the treatment of low-dose rapamycin and was further decreased with the treatment of high-dose rapamycin as examined by Ki67 staining. The phosphorylation of S6K in cystic kidneys was decreased by low-dose rapamycin and further decreased by high-dose rapamycin. Both low-dose and high-dose rapamycin treatment decreased macrophage infiltration and the expression of complement factor B (CFB), monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor-alpha (TNF-α) to a similar level. The expression of CFB, MCP-1, and TNF-α and phosphorylation of S6K were inhibited in WT9-12 cells treated with 10 nm rapamycin at 24 h and 48 h, respectively. Moreover, the phosphorylation of Akt was not increased by 1 nm and 10 nm of rapamycin and enhanced by 1 µm rapamycin treatment. Interestingly, WT9-12 cell proliferation could be inhibited by 1 µm rapamycin. CONCLUSION: Low dose of rapamycin could inhibit inflammation and protect renal function in PKD. Inflammation is more sensitive than cell proliferation in response to rapamycin treatment in PKD.

Activation of GPER1 in macrophages ameliorates UUO-induced renal fibrosis.

Numerous studies have proven the critical role of macrophages in the renal fibrosis process. Notably, G Protein-coupled Estrogen Receptor 1 (GPER1), a novel estrogen receptor, has been shown to play a ubiquitous role in regulating macrophage activities and proinflammatory pathways. However, the precise role of GPER1 in macrophage-mediated renal fibrosis is unknown. In this study, we aimed to investigate the function of macrophage GPER1 in the UUO-induced renal fibrosis model. Compared to vehicle-treated ovariectomized (OVX) female and male unilateral ureteral obstruction (UUO) models, we observed that G-1 (GPER1 agonist)-treated OVX female and male UUO mice had fewer renal fibrotic lesions and less M1 and M2 macrophage infiltration in the kidney tissues. Conversely, Gper1 deletion in male UUO mice accelerated renal fibrosis and increased inflammation. In vitro studies also revealed that GPER1 activation reduced M0 macrophage polarization towards M1 or M2 phenotypes. The RNA-sequencing analysis and immunoblotting indicated that GPER1 activation was primarily involved in downregulating immune pathways activation and inactivating MAPK pathways. Tubular epithelial cells co-cultured with G-1-pretreated M1 macrophages exhibited fewer injuries and immune activation. In addition, fibroblasts co-cultured with G-1-pretreated M2 macrophages showed downregulated extracellular matrix expression. Overall, this is the first study to demonstrate the effect of GPER1 on macrophage-mediated renal fibrosis via inhibition of M1 and M2 macrophage activation. These findings indicate that GPER1 may be a promising therapeutic target for treating renal fibrosis.

Safety and effectiveness of HSK21542 for hemodialysis patients: a multiple ascending dose study.

Background: HSK21542, a novel selective peripherally-restricted κ-opioid receptor agonist has been proven to be a safe and effective analgesic and antipruritic drug in both in vitro and in vivo studies. We aimed to evaluate its safety, pharmacokinetics and efficacy in hemodialysis patients over a 1-week treatment period, and to establish the optimal dosage for a further 12-week stage 2 trial. Methods: In this multiple ascending dose study, hemodialysis patients were randomly assigned to receive HSK21542 (0.05-0.80 µg/kg), or a placebo three times within 2.5 h at the end of each dialysis session for 1 week. Safety evaluations included reports of treatment-emergent adverse events (TEAEs); pharmacokinetics and efficacy outcomes were also assessed. Results: Among the 44 screened patients, 41 were enrolled and completed the trial. The overall incidence of TEAEs was higher in the HSK21542 group compared to the placebo group, with an incidence of 75.0%, 50.0%, 75.0%, and 88.9% in the range of 0.05-0.80 µg/kg. All TEAEs were grade 1 or 2 in severity. HSK21542 exhibited linear pharmacokinetics characteristics within the dose range 0.05-0.80 µg/kg, without drug accumulation after multiple-doses. Compared to the placebo, a significant decrease of the weekly mean Worst Itching Intensity Numerical Rating Scale was found in the HSK21542-0.30 µg/kg group (p = 0.046), but without significant improvement in the Skindex-16 score. Conclusion: HSK21542 was well tolerated in the dose range 0.05-0.80 µg/kg in hemodialysis patients. HSK21542-0.3 µg/kg exhibited promising efficacy in patients with moderate to severe pruritus and warrants a further Stage 2 trial. Clinical Trial Registration: https://clinicaltrials.gov/, identifier NCT04470154.

Histone H3K27 methyltransferase EZH2 regulates apoptotic and inflammatory responses in sepsis-induced AKI.

Rationale: The role of histone methylation modifications in renal disease, particularly in sepsis-induced acute kidney injury (AKI), remains unclear. This study aims to investigate the potential involvement of the histone methyltransferase zeste homolog 2 (EZH2) in sepsis-induced AKI and its impact on apoptosis and inflammation. Methods: We first examined the expression of EZH2 in the kidney of sepsis-induced AKI (LPS injection) mice and LPS-stimulated tubular epithelial cells. We next constructed the EZH2 knockout mice to further confirm the effects of EZH2 on apoptosis and inflammatory response in AKI. And the inflammatory level of epithelial cells can be reflected by detecting chemokines and the chemotaxis of macrophages. Subsequently, we constructed the EZH2 knocked-down cells again and performed Chromatin Immunoprecipitation sequencing to screen out the target genes regulated by EZH2 and the enrichment pathway. Then we confirmed the EZH2 target gene and its regulatory pathway in vivo and in vitro experiments. Experimental results were finally confirmed using another in vivo model of sepsis-induced AKI (cecal perforation ligation). Results: The study found that EZH2 was upregulated in sepsis-induced AKI and that silencing EZH2 could reduce renal tubular injury by decreasing apoptosis and inflammatory response of tubular epithelial cells. EZH2 knockout mice showed significantly reduced renal inflammation and macrophage infiltration. Chromatin immunoprecipitation sequencing and polymerase chain reaction identified Sox9 as a target of EZH2. EZH2 was found to be enriched on the promoter of Sox9. Silencing EZH2 resulted in a significant increase in the transcriptional level of Sox9 and activation of the Wnt/ß-catenin signaling pathway. The study further reversed the effects of EZH2 silencing by silencing Sox9 or administering the Wnt/ß-catenin inhibitor icg001. It was also found that Sox9 positively regulated the expression of ß-catenin and its downstream pathway-related genes. Finally, the study showed that the EZH2 inhibitor 3-deazaneplanocin A significantly alleviated sepsis-induced AKI. Conclusion: Our results indicate that silencing EZH2 can protect renal function by relieving transcriptional inhibition of Sox9, activating the Wnt/ß-catenin pathway, and attenuating tubular epithelial apoptosis and inflammatory response of the renal interstitium. These results highlight the potential therapeutic value of targeting EZH2 in sepsis-induced AKI.

Dehydration Accelerates Cytogenesis and Cyst Growth in Pkd1-/- Mice by Regulating Macrophage M2 Polarization.

Adult autosomal dominant polycystic kidney disease (ADPKD) has been shown to be related as a "third hit" to the occurrence of acute or chronic kidney injury. Here, we examined whether dehydration, as a common kidney risk factor, could cause cystogenesis in chronic-onset Pkd1-/- mice by regulating macrophage activation. First, we confirmed that dehydration accelerated cytogenesis in Pkd1-/- mice and that macrophages infiltrated the kidney tissues even earlier than macroscopic cyst formation. Then, microarray analysis suggested that glycolysis pathway may be involved in macrophage activation in Pkd1-/- kidneys under conditions of dehydration. Further, we confirmed glycolysis pathway was activated and lactic acid (L-LA) was overproduced in the Pkd1-/- kidney under conditions of dehydration. We have already proved that L-LA strongly stimulated M2 macrophage polarization and overproduction of polyamine in macrophage in vitro, and in the present study, we further discovered that M2 polarization-induced polyamine production shortened the primary cilia length by disrupting the PC1/PC2 complex. Finally, the activation of L-LA-arginase 1-polyamine pathway contributed to cystogenesis and progressive cyst growth in Pkd1-/- mice recurrently exposed to dehydration.

Non-Iterative Multiscale Estimation for Spatial Autoregressive Geographically Weighted Regression Models.

Multiscale estimation for geographically weighted regression (GWR) and the related models has attracted much attention due to their superiority. This kind of estimation method will not only improve the accuracy of the coefficient estimators but also reveal the underlying spatial scale of each explanatory variable. However, most of the existing multiscale estimation approaches are backfitting-based iterative procedures that are very time-consuming. To alleviate the computation complexity, we propose in this paper a non-iterative multiscale estimation method and its simplified scenario for spatial autoregressive geographically weighted regression (SARGWR) models, a kind of important GWR-related model that simultaneously takes into account spatial autocorrelation in the response variable and spatial heterogeneity in the regression relationship. In the proposed multiscale estimation methods, the two-stage least-squares (2SLS) based GWR and the local-linear GWR estimators of the regression coefficients with a shrunk bandwidth size are respectively taken to be the initial estimators to obtain the final multiscale estimators of the coefficients without iteration. A simulation study is conducted to assess the performance of the proposed multiscale estimation methods, and the results show that the proposed methods are much more efficient than the backfitting-based estimation procedure. In addition, the proposed methods can also yield accurate coefficient estimators and such variable-specific optimal bandwidth sizes that correctly reflect the underlying spatial scales of the explanatory variables. A real-life example is further provided to demonstrate the applicability of the proposed multiscale estimation methods.

Macrophages promote heat stress nephropathy in mice via the C3a-C3aR-TNF pathway.

Heat-stress nephropathy (HSN) is associated with recurrent dehydration. However, the mechanisms underlying HSN remain largely unknown. In this study, we evaluated the role of dehydration in HSN and kidney injury in mice. Firstly, we found that complement was strongly activated in the mice that were exposed to dehydration; and among complement components, the interaction between C3a and its receptor, C3aR, was more closely associated with kidney injury. Then two-month-old mice were intraperitoneally injected with 2% dimethyl sulfoxide (DMSO) or the C3aR inhibitor SB290157 during dehydration. DMSO-treated mice exhibited excessive macrophage infiltration, renal cell apoptosis, and kidney fibrosis. In contrast, SB290157-treated mice had no apparent kidney injury. By fluorescence-activated cell sorting (FACS), we found that SB290157 treatment in mice remarkably inhibited macrophage infiltration and suppressed CCR2 expression in macrophages. In addition, C3a binding to C3aR promoted macrophage polarization toward the M1 phenotype and increased the production of TNF-α, which induced renal tubular epithelial cell (RTEC) apoptosis in vivo and in vitro. Interestingly, C3a treatment failed to directly induce TNF-α production and apoptosis in RTECs. However, TNF-α production in response to C3a treatment was significantly elevated when RTECs were cocultured with macrophages, suggesting that macrophages rather than RTECs are the target of C3a-C3aR interaction. At last, we proved that infusion of macrophages which highly expressed TNF-α would significantly deteriorate HSN in TNF-KO mice when they were exposed to recurrent dehydration. This study uncovers a novel mechanism underlying the pathogenesis of HSN, and a potential pathway to prevent kidney injury during dehydration.

A Nomogram to Identify Hyperkalemia Risk in Patients with Advanced CKD.

Background: Hyperkalemia is a common and life-threatening complication of CKD. We aimed to develop and validate a nomogram that could identify the risk of hyperkalemia (≥5.5 mmol/L) in patients with CKD. Methods: A retrospective cohort study was performed in adult patients with predialysis advanced CKD (stages ≥3) in 2020-2021 for the outcome of hyperkalemia within 6 months. The training set was used to identify risk factors of hyperkalemia. Then a nomogram was developed by multivariable logistic regression analysis. C-statistics, calibration curves, and decision curve analysis (DCA) were used, and the model was validated in the internal and two external validation sets. Results: In total, 847 patients with advanced CKD were included. In 6 months, 28% of patients had hyperkalemia (234 out of 847). Independent risk factors were: age ≥75 years, higher CKD stages, previous event of serum potassium ≥5.0 mmol/L within 3 months, and comorbidities with heart failure, diabetes, or metabolic acidosis. Then the nomogram on the basis of the risk factors adding the use of renin-angiotensin-aldosterone system inhibitors was constructed. The C-statistic of the model was 0.76 (95% CI, 0.70 to 0.78), and was stable in both the internal validation set (0.73; 95% CI, 0.63 to 0.82) and external validation sets (0.88; 95% CI, 0.84 to 0.95 and 0.82; 95% CI, 0.72 to 0.92). Calibration curves and DCA analysis both found good performances of the nomogram. Conclusion: A feasible nomogram and online calculator were developed and validated to evaluate the risk of hyperkalemia within 6 months in patients with advanced CKD. Patients with CKD and a high risk of hyperkalemia may benefit from intensive monitoring and early triage.

Thrombotic thrombocytopenic purpura developed after pegylated interferon treatment for hepatitis B infection.

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare and life-threatening thrombotic microangiopathy characterized by microangiopathic hemolytic anemia, severe thrombocytopenia, and organ ischemia. It is related to severe deficiency in ADAMTS13, which is usually acquired via ADAMTS13 autoantibodies or inherited via mutations of the ADAMTS13 gene. The etiology of acquired TTP including HIV infection, pregnancy, autoimmune disease, organ transplantation, drugs, malignancy and so on. Here, we firstly reported a patient diagnosed as acquired TTP after pegylated interferon therapy for hepatitis B and COVID-19 vaccination. CASE PRESENTATION: A 36-year-old male attended to our unit with a five-day history of intermittent hematuria and progressive fatigue on January 5th, 2022. He had a 13 years history of hepatitis B infection and undergone pegylated interferon treatment (which was paused for two months because of COVID-19 vaccination) for nearly 3 years. Laboratory evaluation revealed a haemoglobin level of 61 g/L, platelet count of 11 × 109/L, lactate dehydrogenase 2133 U/L. The direct and indirect Coombs test were both negative. On a peripheral blood smear, there were about 18.8% schistocytes. Meanwhile, the results of ADAMTS 13 activity and antibody were < 5% and 181.34 ng/ml (131.25-646.5), respectively CONCLUSION: This case firstly reported the rare complication of TTP after pegylated interferon treatment for hepatitis B and COVID-19 vaccine injection. This unique sign warrants more attention as an early cue of diagnosis of TTP and be aware of the rarity adverse effect of interferon therapy and COVID-19 vaccination.

Efficacy and safety of darbepoetin alfa injection replacing epoetin alfa injection for the treatment of renal anemia in Chinese hemodialysis patients: A randomized, open-label, parallel-group, noninferiority phase III trial.

Background: This study was to explore the clinical efficacy and safety of darbepoetin alfa injection replacing epoetin alfa injection (recombinant human erythropoietin injection, rHuEPO) for the treatment of anemia associated with chronic kidney failure in Chinese patients undergoing hemodialysis. Method: This study was a multicenter, randomized, open-label, intergroup parallel control phase III noninferiority trial from April 19, 2013 to September 9, 2014 at 25 sites. In this study, the members of the darbepoetin alfa group underwent intravenous administration once per week or once every two weeks. The members of the control drug epoetin alfa group underwent intravenous administration two or three times per week. All subjects underwent epoetin alfa administration during the 8-week baseline period. After that, subjects were randomly assigned to the darbepoetin alfa group or epoetin alfa group. The noninferiority in the changes of the average Hb concentrations from the baseline to the end of the evaluation period (noninferiority threshold: -1.0 g/dl) was tested between the two treatments. The time-dependent hemoglobin (Hb) concentration and the maintenance rate of the target Hb concentration (the proportion of subjects with Hb concentrations between 10.0 and 12.0 g/dl) were also evaluated. Iron metabolism, including changes in the serum iron, total iron-binding capacity, ferritin, transferrin saturation, and comparisons of the dose adjustments between the two groups during the treatment period were analyzed further. Adverse events (AEs) were also observed and compared, and the safety was analyzed between the two treatment groups. The conversion rate switching from epoetin alfa to darbepoetin alfa was also discussed. SAS® software version 9.2 was used to perform all statistical analyses. Descriptive statistics were used for all efficacy, safety, and demographic variable analyses, including for the primary efficacy indicators. Results: Four hundred and sixty-six patients were enrolled in this study, and ultimately 384 cases were analyzed for safety, including 267 cases in the darbepoetin alfa group and 117 cases in the epoetin alfa group. There were 211 cases in the per-protocol set, including 152 cases in the darbepoetin alfa group and 59 cases in the epoetin alfa group. The changes in the average Hb concentrations from the baseline to the end of the evaluation period were -0.07 and -0.15 g/dl in the darbepoetin alfa group and epoetin alfa group respectively. The difference between the two groups was 0.08 g/dl (95% confidence interval [CI]: -0.22 to 0.39), and the lower limit of the 95% CI was -0.22 > -1.0 g/dl. The average Hb concentrations of the two groups were 10.88-11.43 g/dl (darbepoetin alfa) and 10.91-11.38 g/dl (epoetin alfa) during the study period of Weeks 0-28, with the maintenance rates of the target Hb concentration ranging within 71%-87% and 78%-95% in the darbepoetin alfa group and epoetin alfa group respectively. During the period of comparison between the two groups, the incidence of AEs in the darbepoetin alfa group was 61.42%, while in the epoetin alfa group it was 56.41%. All of the adverse events and reactions in the study were those commonly associated with hemodialysis. Conclusion: The overall efficacy and safety of darbepoetin alfa for the treatment of Chinese renal anemia patients undergoing hemodialysis are consistent with those of epoetin alfa.

In-center Nocturnal Hemodialysis Reduced the Circulating FGF23, Left Ventricular Hypertrophy, and All-Cause Mortality: A Retrospective Cohort Study.

Fibroblast growth factor 23(FGF23) is the most important biomarker and pathogenic factor in Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD). In the moderate and severe stages of chronic renal failure, abnormally elevated circulating FGF23 can lead to some complications, including myocardial hypertrophy, which is positively correlated with all-cause mortality. However, the circulating FGF23 level of different hemodialysis modalities, the underlying essential regulatory factors, and potential clinical benefits remain to be elucidated. In this retrospective cohort study, 90 in-center nocturnal hemodialysis (INHD) and 90 matched conventional hemodialysis (CHD) patients were enrolled. The complete blood count, intact FGF23(iFGF23), calcium, phosphorus, PTH, and other biochemical and echocardiographic parameters of INHD and CHD patients were collected and analyzed at 1-year follow-up. The all-cause mortality was recorded during the 7-year follow-up. Furthermore, the regulatory factors of iFGF23 and its association with echocardiographic parameters and mortality were investigated by multivariate regression. The levels of iFGF23 and serum phosphate in patients undergoing INHD were significantly lower than those in patients undergoing CHD. The left ventricular volume index (LVMI) in patients with INHD was significantly attenuated and positively correlated with the drop of serum iFGF23. The INHD group had reduced all-cause mortality compared to the CHD group. Multivariate analysis showed that iFGF23 was positively correlated with serum calcium, serum phosphorus, and calcium-phosphate product. The calcium-phosphate product is an independent determining factor of serum iFGF23. Compared with the CHD group, the INHD group presented with a significantly reduced circulating iFGF23 level, which was closely associated with attenuation of left ventricular hypertrophy, but INHD reduced all-cause mortality in an FGF23 independent manner.

Chromatin Methylation Abnormalities in Autosomal Dominant Polycystic Kidney Disease.

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease worldwide and is one of the major causes of end-stage renal disease. PKD1 and PKD2 are two genes that mainly contribute to the development and progression of ADPKD. The precise mechanism is not fully understood. In recent years, epigenetic modification has drawn increasing attention. Chromatin methylation is a very important category of PKD epigenetic changes and mostly involves DNA, histone, and RNA methylation. Genome hypomethylation and regional gene hypermethylation coexist in ADPKD. We found that the genomic DNA of ADPKD kidney tissues showed extensive demethylation by whole-genome bisulphite sequencing, while some regional DNA methylation from body fluids, such as blood and urine, can be used as diagnostic or prognostic biomarkers to predict PKD progression. Histone modifications construct the histone code mediated by histone methyltransferases and contribute to aberrant methylation changes in PKD. Considering the complexity of methylation abnormalities occurring in different regions and genes on the PKD epigenome, more specific therapy aiming to restore to the normal genome should lead to the development of epigenetic treatment.

Anoctamin 1 Inhibition Suppresses Cystogenesis by Enhancing Ciliogenesis and the Ciliary Dosage of Polycystins.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is a ciliopathy characterized by abnormal tubular epithelial proliferation and fluid secretion. Anoctamin 1 (ANO1) is a calcium-dependent chloride channel. However, how ANO1 contributes to ADPKD is largely unexplored. METHODS: Kidney tissues from ADPKD patients, Pkd1RC/RC mice model, WT9-7 human PKD1+⁣/- cells, and 3D culture models in vitro were used. Localization of ANO1 and cilium length were investigated by confocal immunofluorescence. RESULTS: We found that ANO1 was consistently upregulated in human and mouse PKD kidneys. Intriguingly, ANO1 located in a vesicle-like pattern at the ciliary base but not on the ciliary surface. ANO1 deficiency enhanced ciliogenesis and the ciliary dosage of polycystin-2 in human PKD cells, and reduced cyst formation in 3D culture models. Moreover, inhibition of ANO1 abolished the activation of STAT3 and ERK pathways in PKD cells. CONCLUSIONS: Our data indicate ANO1 is a negative regulator for both cilia length and cilia trafficking of polycystin-2 and provide mechanistic insights regarding the therapeutic potential of ANO1 pathway in ADPKD treatment.

Susceptibility of renal fibrosis in diabetes: Role of hypoxia inducible factor-1.

Diabetes may prevent kidney repair and sensitize the kidney to fibrosis or scar formation. To test this possibility, we examined renal fibrosis induced by unilateral ureteral obstruction (UUO) in diabetic mouse models. Indeed, UUO induced significantly more renal fibrosis in both Akita and STZ-induced diabetic mice than in nondiabetic mice. The diabetic mice also had more apoptosis and interstitial macrophage infiltration during UUO. In vitro, hypoxia induced higher expression of the fibrosis marker protein fibronectin in high glucose-conditioned renal tubular cells than in normal glucose cells. Mechanistically, hypoxia induced significantly more hypoxia-inducible factor-1 α (HIF-1 α) in high glucose cells than in normal glucose cells. Inhibition of HIF-1 attenuated the expression of fibronectin induced by hypoxia in high-glucose cells. Consistently, UUO induced significantly higher HIF-1α expression along with fibrosis in diabetic mice kidneys than in nondiabetic kidneys. The increased expression of fibrosis induced by UUO in diabetic mice was diminished in proximal tubule-HIF-1α-knockout mice. Together, these results indicate that diabetes sensitizes kidney tissues and cells to fibrogenesis probably by enhancing HIF-1 activation.

Darbepoetin alfa injection versus epoetin alfa injection for treating anemia of Chinese hemodialysis patients with chronic kidney failure: A randomized, open-label, parallel-group, non-inferiority Phase III trail.

Background: Erythropoietin is a glycoprotein that mainly regulates erythropoiesis. In patients with chronic renal failure with anemia, darbepoetin alfa can stimulate erythropoiesis, correct anemia, and maintain hemoglobin levels. This study was designed to demonstrate the efficacy and safety of darbepoetin alfa injections as being not inferior to epoetin alfa injections (Recombinant Human Erythropoietin injection, rHuEPO) when maintaining hemoglobin (Hb) levels within the target range (10.0-12.0 g/dL) for the treatment of renal anemia. Methods: Ninety-five patients were enrolled in this study from April 15, 2013 to April 10, 2014 at 25 sites. In this study, patients (n = 95) aged 18-70 years were randomized into a once per week intravenous darbepoetin alfa group (n = 56) and a twice or three times per week intravenous epoetin alfa group (n = 39) for 28 weeks, who had anemia with hemoglobin levels between 6 g/dL and 10 g/dL due to chronic kidney disease (CKD) and were undergoing hemodialysis or hemofiltration with ESA-naive (erythropoiesis stimulating agent-naive). The primary efficacy profile was the mean Hb level (the non-inferiority margin was -1.0 g/dL, week 21-28); the secondary efficacy profiles were the Hb increase rate (week 0-4), the target Hb achievement cumulative rate and time, the change trends of the Hb levels, and the target Hb maintenance ratio. Adverse events (AEs) were observed and compared, and the efficacy and safety were analyzed between the two treatment groups. Additionally, the frequencies of dose adjustments between the darbepoetin alfa and epoetin alfa groups were compared during the treatment period. SAS® software version 9.2 was used to perform all statistical analyses. Descriptive statistics were used for all efficacy, safety, and demographic variable analyses, including for the primary efficacy indicators. Results: The mean Hb level was 11.3 g/dL in the darbepoetin alfa group and 10.7 g/dL in the epoetin alfa group, respectively; the difference of the lower limits of the 95% confidence intervals (CI) between the two groups was 0.1 g/dL (>-1.0 g/dL), and non-inferiority was proven; the Hb levels started to increase in the first four weeks at a similar increase rate; no obvious differences were observed between the groups in the target Hb achievement cumulative rates, and the Hb levels as well as the target Hb level maintenance rate changed over time. The incidence of AEs was 62.5% in the darbepoetin alfa group and 76.9% in the epoetin alfa group. All the adverse events observed in the study were those commonly associated with hemodialysis. Conclusion: Darbepoetin alfa intravenously once per week can effectively increase Hb levels and maintain the target Hb levels well, which makes it not inferior to epoetin alfa intravenously twice or three times per week. Darbepoetin alfa shows an efficacy and safety comparable to epoetin alfa for the treatment of renal anemia.

Pancreatic extracorporeal shock wave lithotripsy for a patient concurrent with autosomal dominant polycystic kidney disease: a case report.

Whether pancreatic extracorporeal shock wave lithotripsy (ESWL) is safe for patients with autosomal dominant polycystic kidney disease (ADPKD) is unclear. A woman in her early 30s was admitted to our hospital because of intermittent upper abdominal pain and recurrent pancreatitis. The imaging results confirmed the diagnosis of pancreatic stones and ADPKD. We performed pancreatic ESWL using a third-generation lithotripter to pulverize the pancreatic stones. A maximum of 5000 shock waves was delivered per therapeutic session. A second session of ESWL was performed the next day. The patient developed no adverse events or complications related to pancreatic ESWL. Three years after treatment, the patient had developed no relapse of pancreatitis or abdominal pain. Shock waves do not lead to complications such as hematuria, cyst rupture, or deterioration of the inner bleeding of renal cysts. Multiple kidney cysts are not a contraindication for pancreatic ESWL.

Icariin attenuates renal interstitial fibrosis through G protein-coupled estrogen receptor in a UUO murine model.

BACKGROUND/AIMS: Icariin plays an antifibrotic role in the unilateral ureteral obstruction (UUO) model; however, its primary mechanism has not been elucidated. G protein-coupled estrogen receptor (GPER) has been shown to be associated with fibrosis and mitochondrial biogenesis. In this study, we aimed to investigate the impact of GPER on renal fibrosis and whether icariin attenuates renal fibrosis dependent on GPER. METHODS: In the in vivo study, 10-week-old mice were subjected to the UUO model followed by UUO with icariin, G-15 (a GPER antagonist), and icariin + G-15. GPER expression, renal fibrosis levels, and mitochondrial alterations were measured and analyzed. In an in vitro study, we examined the antifibrotic effect of icariin on rat renal fibroblasts (NRK-49F) via GPER. RESULTS: Consistent with a previous study, icariin significantly attenuated fibrotic markers and protected the kidneys against mitochondrial injuries in the UUO model. However, G-15 exacerbated renal fibrosis and abolished the protective effect of icariin in the UUO model. Furthermore, antagonizing or knocking down GPER in NRK-49F significantly increased fibrotic markers and eliminated the antifibrotic effect of icariin. CONCLUSIONS: Our findings indicate that (1) GPER inhibition exacerbates renal fibrosis, and (2) icariin exerts antifibrotic effects against renal fibrosis through GPER.

Prognostic analysis of crescentic glomerulonephritis with acute kidney injury: a single-center cohort with 5-year follow-up.

BACKGROUND: Crescentic glomerulonephritis (CrGN) represents a severe form of glomerular injury that results in high rates of renal failure. This study aimed to investigate the influence of potential clinical and pathological factors on renal outcomes of CrGN; and the relationship between 3-month and 5-year follow-up as well. METHODS: The cohort enrolled patients diagnosed of biopsy proven CrGN with acute kidney injury(AKI) from January 1, 2010, to January 1, 2018 in Shanghai Changzheng Hospital and followed up for 5 years. RESULTS: A total of 56 patients were included, among whom 11 patients (19.6%) had type I, 12 (21.4%) had type II, and 33 (58.9%) had type III CrGN. Patients with type II CrGN tended to have a lower crescent score, less renal tubular damage, and lower serum creatinine than the other two types. Three-month cumulative renal survival rates of types I, II, and III CrGN were 45.5%, 66.7%, and 48.5%, respectively. Five-year cumulative renal survival rates of types I, II, and III CrGN were 27.2%, 83.3%, and 36.4%, respectively. The Kappa Consistency Test between 3-month and 5-year outcomes was 0.573(P < 0.001). Cox regression model showed that in-hospital dialysis was an indicative renal survival factor in 3 months (HR 15.670, 95% CI 2.987-82.210, P = 0.001). It also showed that the crescent score had an unfavorable effect for renal survival in 5 years (HR 1.750 95% CI 1.018-3.009, P = 0.043). CONCLUSIONS: Clinical manifestations and outcomes varied by different CrGN types. Three-month outcomes could partially reflect the 5-year outcomes. Severity of crescents was an independent risk factor for renal survival in CrGN.