Transcription factor Nrf2 activation regulates NETosis, endothelial injury, and kidney disease in myeloperoxidase-positive antineutrophil cytoplasmic antibody-associated vasculitis.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systemic autoimmune disease pathologically characterized by vascular necrosis with inflammation. During AAV development, activated neutrophils produce reactive oxygen species (ROS), leading to the aberrant formation of neutrophil extracellular traps (NETs) via NETosis and subsequent fibrinoid vascular necrosis. Nuclear factor-erythroid 2-related factor 2 (Nrf2) functions as an intracellular defense system to counteract oxidative stress by providing antioxidant properties. Herein, we explored the role of Nrf2 in the pathogenesis of AAV. The role and mechanism of Nrf2 in ANCA-stimulated neutrophils and subsequent endothelial injury were evaluated in vitro using Nrf2 genetic deletion and Nrf2 activator treatment. In corresponding in vivo studies, the role of Nrf2 in ANCA-transfer AAV and spontaneous AAV murine models was examined. Pharmacological activation of Nrf2 in vitro suppressed ANCA-induced NET formation via the inhibition of ROS. In contrast, NET formation was enhanced in Nrf2-deficient neutrophils. Furthermore, Nrf2 activation protected endothelial cells from ANC-induced NETs-mediated injury. In vivo, Nrf2 activation ameliorated glomerulonephritis in two AAV models by upregulating antioxidants and inhibiting ROS-mediated NETs. Furthermore, Nrf2 activation restrained the expansion of splenic immune cells, including T lymphocytes and limited the infiltration of Th17 cells into the kidney. In contrast, Nrf2 genetic deficiency exacerbated vasculitis in a spontaneous AAV model. Thus, the pathophysiological process in AAV may be downregulated by Nrf2 activation, potentially leading to a new therapeutic strategy by regulating NETosis.

Protocol for the nationwide registry of patients with polycystic kidney disease: japanese national registry of PKD (JRP).

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD) are major genetic polycystic kidney diseases that can progress to end-stage kidney disease (ESKD). Longitudinal data on the clinical characteristics associated with clinical outcomes in polycystic kidney disease (PKD), including the development of ESKD and cardiovascular disease (CVD) are lacking in Japan. To address this unmet need the authors are establishing a novel, web-based, Nationwide Cohort Registry Study-the Japanese Registry of PKD (JRP). METHODS: The JRP is a prospective cohort study for ADPKD (aim to recruit n = 1000 patients), and both a retrospective and prospective study for ARPKD (aim to recruit n = 100). In the prospective registry, patients will be followed-up for 10 years every 6 months and 12 months for patients with ADPKD and ARPKD, respectively. Data collection will be recorded on Research Electronic Data Capture (REDCap) starting on April 1, 2024, with recruitment ending on March 31, 2029. (jRCT 1030230618). RESULTS: Data to be collected include: baseline data, demographics, diagnostic and genetic information, radiological and laboratory findings, and therapeutic interventions. During follow-up, clinical events such as development of ESKD, hospitalization, occurrence of extra kidney complications including CVD events, and death will be recorded, as well as patient-reported health-related quality of life for patients with ADPKD. CONCLUSIONS: The JRP is the first nationwide registry study for patients with ADPKD and ARPKD in Japan, providing researchers with opportunities to advance knowledge and treatments for ADPKD and ARPKD, and to inform disease management and future clinical practice.

Public support for patients with intractable diseases in Japan: impact on clinical indicators from nationwide registries in patients with autosomal dominant polycystic kidney disease.

BACKGROUND: Clinical practice guidelines recommend antihypertensive and tolvaptan therapies for patients with autosomal dominant polycystic kidney disease (ADPKD) in Japan. However, tolvaptan therapy may pose an economic burden. The Japanese Ministry of Health, Labour and Welfare supports patients with intractable diseases. This study aimed to confirm the impact of the intractable disease system in Japan on the clinical treatment of ADPKD. METHODS: We analyzed the data of 3768 patients with ADPKD having a medical subsidy certificate from the Japanese Ministry of Health, Labour and Welfare in 2015-2016. The following quality indicators were use: the adherence rate to the 2014 clinical practice guideline for polycystic kidney disease (prescription rates of antihypertensive agents and tolvaptan in this cohort) and the number of Japanese patients with ADPKD nationwide started on renal replacement therapy in 2014 and 2020. RESULTS: Compared with new applications from 2015 to 2016, the prescription rates of antihypertensives and tolvaptan for the indicated patients at the 2017 renewal application increased by 2.0% (odds ratio = 1.41, p = 0.008) and 47.4% (odds ratio = 10.1, p > 0.001), respectively. These quality indicators improved with antihypertensive treatment, especially in patients with chronic kidney disease stages 1-2 (odds ratio = 1.79, p = 0.013) and in those aged < 50 years (odds ratio = 1.70, p = 0.003). The number of patients with ADPKD who were started on renal replacement therapy in Japan decreased from 999 in 2014 to 884 in 2020 in the nationwide database (odds ratio = 0.83, p < 0.001). CONCLUSIONS: The Japanese public intractable disease support system contributes to improvement of ADPKD treatment.

Deep learning analysis of clinical course of primary nephrotic syndrome: Japan Nephrotic Syndrome Cohort Study (JNSCS).

BACKGROUND: Prognosis of nephrotic syndrome has been evaluated based on pathological diagnosis, whereas its clinical course is monitored using objective items and the treatment strategy is largely the same. We examined whether the entire natural history of nephrotic syndrome could be evaluated using objective common clinical items. METHODS: Machine learning clustering was performed on 205 cases from the Japan Nephrotic Syndrome Cohort Study, whose clinical parameters, serum creatinine, serum albumin, dipstick hematuria, and proteinuria were traceable after kidney biopsy at 5 measured points up to 2 years. The clinical patterns of time-series data were learned using long short-term memory (LSTM)-encoder-decoder architecture, an unsupervised machine learning classifier. Clinical clusters were defined as Gaussian mixture distributions in a two-dimensional scatter plot based on the highest log-likelihood. RESULTS: Time-series data of nephrotic syndrome were classified into four clusters. Patients in the fourth cluster showed the increase in serum creatinine in the later part of the follow-up period. Patients in both the third and fourth clusters were initially high in both hematuria and proteinuria, whereas a lack of decline in the urinary protein level preceded the worsening of kidney function in fourth cluster. The original diseases of fourth cluster included all the disease studied in this cohort. CONCLUSIONS: Four kinds of clinical courses were identified in nephrotic syndrome. This classified clinical course may help objectively grasp the actual condition or treatment resistance of individual patients with nephrotic syndrome.

Increased urinary exosomal SYT17 levels in chronic active antibody-mediated rejection after kidney transplantation via the IL-6 amplifier.

Chronic active antibody-mediated rejection (CAAMR) is a particular problem in kidney transplantation (KTx), and ~25% of grafts are lost by CAAMR. Further, the pathogenesis remains unclear, and there is no effective cure or marker. We previously found that a hyper NFκB-activating mechanism in non-immune cells, called the IL-6 amplifier, is induced by the co-activation of NFκB and STAT3, and that this activation can develop various chronic inflammatory diseases. Here, we show that synaptotagmin-17 (SYT17) is increased in an exosomal fraction of the urine from CAAMR patients, and that this increase is associated with activation of the IL-6 amplifier. Immunohistochemistry showed that SYT17 protein expression was increased in renal tubule cells of the CAAMR group. While SYT17 protein was not detectable in whole-urine samples by western blotting, urinary exosomal SYT17 levels were significantly elevated in the CAAMR group compared to three other histology groups (normal, interstitial fibrosis and tubular atrophy, and calcineurin inhibitors toxicity) after KTx. On the other hand, current clinical laboratory data could not differentiate the CAAMR group from these groups. These data suggest that urinary exosomal SYT17 is a potential diagnostic marker for CAAMR.

Factors predicting decline in renal function and kidney volume growth in autosomal dominant polycystic kidney disease: a prospective cohort study (Japanese Polycystic Kidney Disease registry: J-PKD).

BACKGROUND: Factors affecting decline in renal function and cyst growth in patients with autosomal polycystic kidney disease (ADPKD) are not fully described, particularly in Japan. METHODS: This was the first multi-facility, prospective, observational cohort study conducted in ADPKD patients at 14 centers in Japan. Patients in the J-PKD registry were assessed from December 2009 to June 2012 (follow-up until June 2017). Patients' data including estimated glomerular filtration rate (eGFR) and total kidney volume (TKV) were assessed initially and a maximum of five times annually. Contributing factors to eGFR decline and TKV growth were identified using multiple linear regression analysis. RESULTS: Of the 340 patients in the J-PKD registry, data analysis was performed for 192 patients in whom serial changes for both eGFR and TKV were obtained. eGFR slope, eGFR change, and TKV change values were as follows: - 2.7 (- 4.2 to - 1.5) (ml/min/1.73 m2/year), - 5.0 (- 9.6 to - 2.3) (%/year), and 4.78 (0.86-8.22) (%/year), respectively. Lower high-density lipoprotein (HDL) cholesterol was an independent predictor of eGFR decline, using both eGFR slope and change (P = 0.04, P = 0.02, respectively), whereas lower hemoglobin and higher uric acid were significantly associated with greater eGFR change only (P = 0.02, P = 0.002, respectively). Younger age and higher fasting blood sugar were independent predictors of greater TKV change (P = 0.01, P = 0.02, respectively). CONCLUSIONS: This real-world study in Japan identified risk factors for renal function decline in ADPKD patients. These included lower HDL cholesterol, lower hemoglobin and higher uric acid for eGFR decline, and youth and higher blood sugar levels for TKV growth.

Recombinant thrombomodulin ameliorates autoimmune vasculitis via immune response regulation and tissue injury protection.

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is characterized by necrotizing vasculitis with the presence of pathogenic ANCA. ANCA can potentially cause neutrophil activation and induce neutrophil extracellular traps (NETs), resulting in endothelial damage as well as activation of autoreactive B cells and alternative complement pathway. Recombinant thrombomodulin (rTM) protects the endothelium from vascular injury during disseminated intravascular coagulation, thus we hypothesized that rTM ameliorates necrotizing vasculitis in AAV. In this study, rTM was administered in an experimental AAV rat model. Treatment of experimental AAV rats with rTM improved pulmonary hemorrhage and glomerulonephritis, with a suppression of ANCA production and NETs formation. In addition, in vitro experiments showed that rTM bound to neutrophils via Mac-1 (macrophage-1 antigen) and inhibited ANCA-induced NETs formation accompanied by a suppression of histone citrullination, leading to a protection of the endothelium from NETs toxicity. Additionally, rTM affected lymphocytes leading to the inhibition of pro-inflammatory cytokine/chemokin in PBMC during the antibody production process, which might indirectly be involved in the reduction of pathogenic ANCA. Our data revealed that the rTM could ameliorate autoimmune vasculitis through a combination of different biological mechanisms.

The relationship between liver cyst volume and QOL in Japanese ADPKD patients.

BACKGROUND: Although it is widely accepted that the autosomal dominant polycystic kidney disease (ADPKD) patients with large liver cysts have a significant decrement in quality of life (QOL), there is insufficient evidence that clearly demonstrates the relationship between the size of the liver cysts and QOL. Therefore, we started this prospective longitudinal study to investigate the impact of liver cysts on QOL. METHODS: We grouped the 111 included ADPKD patients into 4 groups (control group A; < 25%, group B; 25-49%, group C; 50-75%, group D; > 75%) according to liver cysts-parenchyma ratio (CPR). QOL was measured by FANLTC + FACT-Hep scores. We compared QOL scores and several clinical parameters amongst these groups for 3 years. RESULTS: The number of patients in group A, B, C, and D was 31, 14, 14, and 23, respectively. Although there were no significant differences in AST (p = 0.107), ALT (p = 0.925), and serum albumin (p = 0.212) between the four groups, platelet count was significantly decreased along with the extension of cyst volume (p = 0.030). Overall, the mean FANLTC and FACT-Hep scores were 71.8 ± 12.5, and 32.4 ± 5.8, respectively. FANLTC (p = 0.017) and FACT-Hep scores (p = 0.003) were significantly decreased with increasing cyst volume. From the data collected at the time of registration, multivariate linear regression analysis demonstrated that the CPR had a significant influence on FANLTC and FACT-Hep scores. CONCLUSION: In this cross-sectional and prospective longitudinal study, we demonstrate the relationship between liver cyst volume and QOL in ADPKD patients. We hope to establish the long-term influence on QOL in this ongoing prospective longitudinal study.

Better remission rates in elderly Japanese patients with primary membranous nephropathy in nationwide real-world practice: The Japan Nephrotic Syndrome Cohort Study (JNSCS).

BACKGROUND: The aim of the present study was to clarify the prevalence of immunosuppressive drug use and outcomes in elderly and non-elderly patients with primary membranous nephropathy (MN) in nationwide real-world practice in Japan. PATIENTS AND METHODS: Between 2009 and 2010, 374 patients with primary nephrotic syndrome were enrolled in the cohort study (The Japan Nephrotic Syndrome Cohort Study, JNSCS), including 126 adult patients with MN. Their clinical characteristics were compared with those of nephrotic patients with primary MN registered in a large nationwide registry (The Japan Renal Biopsy Registry, J-RBR). Outcomes and predictors in the elderly (≥ 65 years) and non-elderly groups were identified. RESULTS: Similar clinical characteristics were observed in JNSCS patients and J-RBR patients (n = 1808). At the early stage of 1 month, 84.1% of patients were treated with immunosuppressive therapies. No significant differences were observed in therapies between age groups. However, elderly patients achieved complete remission (CR) more frequently than non-elderly patients, particularly those treated with therapies that included corticosteroids. No significant differences were noted in serum creatinine (sCr) elevations at 50 or 100%, end-stage kidney disease, or all-cause mortality between age groups. Corticosteroids were identified as an independent predictor of CR (HR 2.749, 95%CI 1.593-4.745, p = 0.000) in the multivariate Cox's model. sCr levels, hemoglobin levels, immunosuppressants, clinical remission, and relapse after CR were independent predictors of sCr × 1.5 or × 2.0. CONCLUSION: Early immunosuppressive therapy including corticosteroids for primary MN showed better remission rates in elderly patients in a nationwide cohort study.

Incidence of remission and relapse of proteinuria, end-stage kidney disease, mortality, and major outcomes in primary nephrotic syndrome: the Japan Nephrotic Syndrome Cohort Study (JNSCS).

BACKGROUND: Despite recent advances in immunosuppressive therapy for patients with primary nephrotic syndrome, its effectiveness and safety have not been fully studied in recent nationwide real-world clinical data in Japan. METHODS: A 5-year cohort study, the Japan Nephrotic Syndrome Cohort Study, enrolled 374 patients with primary nephrotic syndrome in 55 hospitals in Japan, including 155, 148, 38, and 33 patients with minimal change disease (MCD), membranous nephropathy (MN), focal segmental glomerulosclerosis (FSGS), and other glomerulonephritides, respectively. The incidence rates of remission and relapse of proteinuria, 50% and 100% increases in serum creatinine, end-stage kidney disease (ESKD), all-cause mortality, and other major adverse outcomes were compared among glomerulonephritides using the Log-rank test. Incidence of hospitalization for infection, the most common cause of mortality, was compared using a multivariable-adjusted Cox proportional hazard model. RESULTS: Immunosuppressive therapy was administered in 339 (90.6%) patients. The cumulative probabilities of complete remission within 3 years of the baseline visit was ≥ 0.75 in patients with MCD, MN, and FSGS (0.95, 0.77, and 0.79, respectively). Diabetes was the most common adverse events associated with immunosuppressive therapy (incidence rate, 71.0 per 1000 person-years). All-cause mortality (15.6 per 1000 person-years), mainly infection-related mortality (47.8%), was more common than ESKD (8.9 per 1000 person-years), especially in patients with MCD and MN. MCD was significantly associated with hospitalization for infection than MN. CONCLUSIONS: Patients with MCD and MN had a higher mortality, especially infection-related mortality, than ESKD. Nephrologists should pay more attention to infections in patients with primary nephrotic syndrome.

The presence of anti-neutrophil extracellular trap antibody in patients with microscopic polyangiitis.

OBJECTIVE: Although ANCA is the major autoantibody in patients with ANCA-associated vasculitis, previous studies have suggested the presence of anti-neutrophil extracellular trap (NET) antibody in patients with microscopic polyangiitis (MPA), one type of ANCA-associated vasculitis. In this study, we aimed to determine the prevalence and pathogenic role of anti-NET antibody (ANETA) in MPA. METHODS: We examined the presence or absence of ANETA in sera obtained from 19 MPA patients by indirect immunofluorescence. We compared the clinical parameters, including age, sex, MPO-ANCA, creatinine, CRP, MPO-DNA complexes and vasculitis activity, in ANETA-positive and ANETA-negative MPA patients. We investigated the serum NET induction and degradation abilities of ANETA-positive and ANETA-negative MPA patients with reference to healthy controls (n = 8). Furthermore, we assessed the relationship between ANETA and the effect of IgG depletion on the serum NET degradation ability. RESULTS: ANETA was present in 10 of the 19 MPA patients. There was no significant difference in the clinical parameters in ANCA-positive and ANCA-negative MPA patients. Although the NET induction ability was higher and the NET degradation ability was lower in MPA sera than those in healthy controls, these abilities were not different between ANETA-positive and ANETA-negative MPA sera. Interestingly, the NET degradation ability in some sera with ANETA was markedly increased by IgG depletion. CONCLUSION: Some MPA patients produce ANETA and some ANETA possess an inhibitory function against the serum NET degradation ability. Although further studies are needed, ANETA is worthy of attention in order to understand the pathophysiology of MPA.

Initial experience with the use of tris-acryl gelatin microspheres for transcatheter arterial embolization for enlarged polycystic liver.

PURPOSE: To assess the safety and effectiveness of transcatheter arterial embolization (TAE) with tris-acryl gelatin microspheres for patients with symptomatic enlarged polycystic liver disease (PCLD). MATERIALS AND METHODS: This prospective study was approved by our hospital's institutional review board and planned for patients with symptoms related to enlarged PCLD, such as distended abdomen, gastrointestinal obstruction and abdominal pain. Hemi-hepatic embolization with tris-acryl gelatin microspheres was performed in the hepatic artery supplying the hepatic lobe that showed the predominant presence of cysts. Each patient underwent an assessment of liver function, a questionnaire survey about symptoms, measurement of the estimated volume of the whole liver before and after TAE, and an assessment of complications associated with TAE. RESULTS: Five patients (four females, one male; mean age 52.6 ± 9.1 years) were treated. All five patients successfully completed TAE. The left lobe was treated in three patients and the right in two. After TAE, post-embolization syndrome and transient elevation of white blood cells, aspartate aminotransferase, and alanine aminotransferase occurred in all patients, but none developed hepatic insufficiency or severe complications. The mean whole liver volume was 7406 ± 2323 mL before TAE, and 6995 ± 2139 mL (95.1 ± 5.2% of the pre-therapeutic value) at 3 months and 6855 ± 2246 mL (93.3 ± 9.7%) at 12 months after TAE. Three of the five patients reported an improvement of clinical symptoms within 12 months after TAE. CONCLUSION: TAE with microspheres can be a safe and effective treatment for symptomatic enlarged PCLD.

Regional variations in immunosuppressive therapy in patients with primary nephrotic syndrome: the Japan nephrotic syndrome cohort study.

BACKGROUND: The lack of high-quality clinical evidences hindered broad consensus on optimal therapies for primary nephrotic syndromes. The aim of the present study was to compare prevalence of immunosuppressive drug use in patients with primary nephrotic syndrome across 6 regions in Japan. METHODS: Between 2009 and 2010, 380 patients with primary nephrotic syndrome in 56 hospitals were enrolled in a prospective cohort study [Japan Nephrotic Syndrome Cohort Study (JNSCS)], including 141, 151, and 38 adult patients with minimal change disease (MCD), membranous nephropathy (MN), and focal segmental glomerulosclerosis (FSGS), respectively. Their clinical characteristics were compared with those of patients registered in a large nationwide registry of kidney biopsies [Japan Renal Biopsy Registry (J-RBR)]. The regional prevalence of use of each immunosuppressive drug was assessed among adult MCD, MN, and FSGS patients who underwent immunosuppressive therapy in the JNSCS (n = 139, 127, and 34, respectively). Predictors of its use were identified using multivariable-adjusted logistic regression models. RESULTS: The clinical characteristics of JNSCS patients were comparable to those of J-RBR patients, suggesting that the JNSCS included the representatives in the J-RBR. The secondary major immunosuppressive drugs were intravenous methylprednisolone [n = 33 (24.6%), 24 (19.7%), and 9 (28.1%) in MCD, MN, and FSGS, respectively] and cyclosporine [n = 25 (18.7%), 62 (50.8%), and 16 (50.0%), respectively]. The region was identified as a significant predictor of use of intravenous methylprednisolone in MCD and MN patients. CONCLUSION: Use of intravenous methylprednisolone for MCD and MN differed geographically in Japan. Its efficacy should be further evaluated in a well-designed trial.

Interferon-inducible Mx1 protein is highly expressed in renal tissues from treatment-naïve lupus nephritis, but not in those under immunosuppressive treatment.

OBJECTIVES: The aim of this study was to clarify the consequences of Mx1, one of the IFN-inducible proteins, in the peripheral blood as well as in renal tissues in patients with systemic lupus erythematosus (SLE). PATIENTS AND METHODS: Mx1 protein concentrations in (PBMCs) from 18 SLE patients mostly in their stable disease status, 11 IgA nephropathy (IgAN) patients, 5 ANCA-associated vasculitis (AAV) patients and 16 healthy controls were measured using enzyme-linked immunosorbent assay (ELISA). Mx1 expression in renal specimens from 18 patients with lupus nephritis (LN), 18 with IgAN and 10 with AAV were evaluated using immunohistochemistry. RESULTS: Mx1 protein concentrations in lysates of PBMCs were significantly higher in SLE patients compared with those in other three groups. Mx1-positive area in renal tissues was significantly dominant in both glomeruli and renal tubules of LN compared with other renal diseases. Renal Mx1 protein levels were lower in LN after immunosuppressive treatment, compared with those from immunosuppressant-naïve patients. CONCLUSION: Mx1 levels were upregulated in lupus peripheral blood even when their disease activities were stable. On the other hand, Mx1 was highly expressed in kidneys from patients with LN before treatment, which was decreased after immunosuppressive treatment. These results suggest that Mx1 is a potential marker for the diagnosis of SLE in the peripheral blood and also for the activity of lupus nephritis in the kidney.

Branched-chain amino acids enhance cyst development in autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by the progressive development of kidney and liver cysts. The mammalian target of rapamycin (mTOR) cascade is one of the important pathways regulating cyst growth in ADPKD. Branched-chain amino acids (BCAAs), including leucine, play a crucial role to activate mTOR pathway. Therefore, we administered BCAA dissolved in the drinking water to Pkd1flox/flox:Mx1-Cre (cystic) mice from four to 22 weeks of age after polyinosinic-polycytidylic acid-induced conditional Pkd1 knockout at two weeks of age. The BCAA group showed significantly greater kidney/body weight ratio and higher cystic index in both the kidney and liver compared to the placebo-treated mice. We found that the L-type amino acid transporter 1 that facilitates BCAA entry into cells is strongly expressed in cells lining the cysts. We also found increased cyst-lining cell proliferation and upregulation of mTOR and mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathways in the BCAA group. In vitro, we cultured renal epithelial cell lines from Pkd1 null mice with or without leucine. Leucine was found to stimulate cell proliferation, as well as activate mTOR and MAPK/ERK pathways in these cells. Thus, BCAA accelerated disease progression by mTOR and MAPK/ERK pathways. Hence, BCAA may be harmful to patients with ADPKD.

The responses of macrophages in interaction with neutrophils that undergo NETosis.

Neutrophil extracellular traps (NETs) are net-like chromatin fibers decorated with antimicrobial proteins, which are released from dying neutrophils. The death of neutrophils with NET formation is called NETosis. Although NETs play important roles in the innate immunity, especially in the elimination of microbes, the extracellular release of DNA and intra-cytoplasmic/nuclear proteins can, on the other hand, result in diverse adversities to the hosts. Therefore, NETosis is adequately regulated in vivo. Currently, two mechanisms, namely DNase I-dependent digestion and phagocytosis by macrophages, have been shown as such regulatory mechanisms. In this study, we focused on the interaction of macrophages and neutrophils that underwent NETosis. Results demonstrated that macrophages displayed a phenotype-dependent response after degradation of NETs. Several hours after the interaction, M2 macrophages induced a pro-inflammatory response, while M1 macrophages underwent cell death with nuclear decondensation. This nuclear decondensation of M1 macrophages occurred in a peptidylarginine deiminase 4-dependent manner and resulted in a local release of extracellular DNA. Thereafter, M1 macrophages degraded DNA derived from themselves in a caspase-activated DNase-dependent manner resulting in the clearance of extracellular DNA within 24 h. This transient increase and subsequent clearance mechanism of extracellular DNA seems very reasonable in terms of the double-edged sword-like property of NETs. The collective findings demonstrate a novel phenotype- and time-dependent regulation of NETosis by macrophages.

Transcatheter Arterial Embolization with Ethanol Injection in Symptomatic Patients with Enlarged Polycystic Kidneys.

PURPOSE: To evaluate the safety and effectiveness of transcatheter arterial embolization (TAE) with ethanol in symptomatic patients with enlarged polycystic kidney disease. MATERIALS AND METHODS: This prospective study was institutional review board approved and was planned for patients with symptoms related to enlarged polycystic kidney disease, such as a markedly distended abdomen, gastroesophageal reflux, and abdominal pain. At the time of TAE, all patients were undergoing dialysis therapy for chronic renal failure, and their urinary volume had decreased to less than 500 mL per day. Bilateral renal TAE with absolute ethanol was performed, and changes in kidney volume, clinical symptoms, laboratory data, and complications were evaluated after TAE. The differences in patients' kidney volumes, clinical symptoms, abdominal circumference, and dry weights before and after TAE were analyzed with a mixed effect model. RESULTS: Fifteen patients (seven men and eight women; mean age, 57.7 years ± 5.3 [standard deviation]) were treated. Among the 15 patients, the follow-up period was 24 months in 13 patients, 6 months in one patient, and 3 months in one patient. The mean kidney volume was 3380 mL before renal TAE, and at 3, 12, and 24 months after TAE, it significantly decreased to 60.9%, 39.8%, and 32.1% of the pretherapeutic value, respectively (P < .001). All patients reported improved clinical symptoms within 3 months after TAE (P < .001). Abdominal circumferences were significantly decreased after TAE (P < .001). The dry weights also continued to significantly decreased until 6 months after TAE (P < .001), at which point they began to slightly increase until 24 months after TAE. Abdominal pain, nausea, and inflammatory response developed in all patients after TAE, but these symptoms improved with conservative treatment. Abscess formation was found in one kidney, and drainage catheter placement was performed. No major complications related to TAE occurred in the remaining patients. CONCLUSION: Renal contraction therapy by TAE with ethanol injection appears to be a safe and effective treatment in patients with symptomatic enlarged polycystic kidney disease.

Outcomes of primary nephrotic syndrome in elderly Japanese: retrospective analysis of the Japan Renal Biopsy Registry (J-RBR).

BACKGROUND AND OBJECTIVES: There are very little data available regarding nephrotic syndrome (NS) in elderly (aged ≥65 years) Japanese. The aim of this study was to examine the causes and outcomes of NS in elderly patients who underwent renal biopsies between 2007 and 2010. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: From July 2007 to June 2010, all of the elderly (aged ≥65 years) Japanese primary NS patients who underwent native renal biopsies and were registered in the Japan renal biopsy registry (J-RBR; 438 patients including 226 males and 212 females) were identified. From this cohort, 61 patients [28 males and 33 females including 29, 19, 6, 4, and 3 patients with membranous nephropathy (MN), minimal change nephrotic syndrome (MCNS), focal segmental glomerulosclerosis (FSGS), membranoproliferative glomerulonephritis (MPGN), and other conditions, respectively] were registered from the representative multi-centers over all districts of Japan, and analyzed retrospectively. The treatment outcome was assessed using proteinuria-based criteria; i.e., complete remission (CR) was defined as urinary protein level of <0.3 g/day or g/g Cr, and incomplete remission type I (ICR-I) was defined as urinary protein level of <1.0-0.3 g/day or g/g Cr, and renal dysfunction was defined as a serum creatinine (Cr) level of 1.5 times the baseline level. RESULTS: In this elderly primary NS cohort, MN was the most common histological type of NS (54.8 %), followed by MCNS (19.4 %), FSGS (17.4 %), and MPGN (8.4 %). Of the patients with MN, MCNS, or FSGS, immunosuppressive therapy involving oral prednisolone was performed in 25 MN patients (86.2 %), 18 MCNS patients (94.7 %), and all 6 FSGS patients (100 %). CR was achieved in all 19 (100 %) MCNS patients. In addition, CR and ICR-I were achieved in 16 (55.2 %) and 18 (62.1 %) MN patients and 4 (66.7 %) and 5 (83.3 %) FSGS patients, respectively. There were significant differences in the median time to CR among the MCNS, FSGS, and MN patients (median: 26 vs. 271 vs. 461 days, respectively, p < 0.001), and between the elderly (65-74 years, n = 7) and very elderly (aged ≥75 years, n = 12) MCNS patients (7 vs. 22 days, p = 0.037). Relapse occurred in two (6.9 %) of the MN and nine (47.4 %) of the MCNS patients. Renal dysfunction was observed in five (7.2 %) of the MN patients. Serious complications developed in eight (14.8 %) patients, i.e., two (3.7 %) patients died, four (7.4 %, including three MCNS patients) were hospitalized due to infectious disease, and two (3.7 %) developed malignancies. The initiation of diabetic therapy was necessary in 14 of the 61 patients (23.0 %) with much higher initial steroid dosage. CONCLUSION: Renal biopsy is a valuable diagnostic tool for elderly Japanese NS patients. In this study, most of elderly primary NS patients respond to immunosuppressive therapy with favorable clinical outcomes. On the other hand, infectious disease is a harmful complication among elderly NS patients, especially those with MCNS. In future, modified clinical guidelines for elderly NS patients should be developed.