An angiotensin II type 1 receptor binding molecule has a critical role in hypertension in a chronic kidney disease model.

Angiotensin II type 1 receptor-associated protein (ATRAP) promotes AT1R internalization along with suppression of hyperactivation of tissue AT1R signaling. Here, we provide evidence that renal ATRAP plays a critical role in suppressing hypertension in a mouse remnant kidney model of chronic kidney disease. The effect of 5/6 nephrectomy on endogenous ATRAP expression was examined in the kidney of C57BL/6 and 129/Sv mice. While 129/Sv mice with a remnant kidney showed decreased renal ATRAP expression and developed hypertension, C57BL/6 mice exhibited increased renal ATRAP expression and resistance to progressive hypertension. Consequently, we hypothesized that downregulation of renal ATRAP expression is involved in pathogenesis of hypertension in the remnant kidney model of chronic kidney disease. Interestingly, 5/6 nephrectomy in ATRAP-knockout mice on the hypertension-resistant C57BL/6 background caused hypertension with increased plasma volume. Moreover, in knockout compared to wild-type C57BL/6 mice after 5/6 nephrectomy, renal expression of the epithelial sodium channel α-subunit and tumor necrosis factor-α was significantly enhanced, concomitant with increased plasma membrane angiotensin II type 1 receptor in the kidneys. Thus, renal ATRAP downregulation is involved in the onset and progression of blood pressure elevation caused by renal mass reduction, and implicates ATRAP as a therapeutic target for hypertension in chronic kidney disease.

Immunohistochemistry of Vasohibin-2 in Human Kidney Disease : Implications in Impaired Glucose Tolerance and Reduced Renal Function.

Several angiogenesis-related factors are known to play important roles in the pathogenesis of kidney disease. Vasohibin-2 (VASH-2) was recently reported as a novel proangiogenic factor. Although VASH-2 was demonstrated to accelerate tumor angiogenesis, its roles in non-tumor processes including renal disease have not been well elucidated yet. Here, we performed a retrospective study including an immunohistochemical analysis of human kidney biopsy specimens from 82 Japanese patients with a variety of kidney diseases, and we evaluated the correlations between the immunoreactivity of VASH-2 and the patients' clinicopathological parameters. VASH-2 immunoreactivity was detected in varying degrees in renal tubules as well as in peritubular capillaries and vasa recta. The cortical and medullary tubule VASH-2+ scores were correlated with the presence of hypertension, and the medullary tubule VASH-2+ score was significantly correlated with the blood glucose (p=0.029, r=0.35) and hemoglobin A1c levels (p=0.0066, r=0.39). Moreover, decreased VASH-2+ scores in the vasa recta were associated with reduced renal function (p=0.0003). These results suggest that VASH-2 could play an important role in the pathogenesis of renal diseases, and that VASH-2 is closely associated with hypertension and impaired glucose tolerance.

Urinary Albumin Levels Predict Development of Acute Kidney Injury After Pediatric Cardiac Surgery: A Prospective Observational Study.

OBJECTIVE: Mortality and morbidity of acute kidney injury (AKI) after cardiac surgery still remain high. The authors undertook the present study to evaluate the utility of early postoperative urinary albumin (uAlb) as a diagnostic marker for predicting occurrence of AKI and its severity in pediatric patients undergoing cardiac surgery. DESIGN: A prospective observational study. SETTING: A single-institution university hospital. PARTICIPANTS: All patients<18 years of age who underwent repair of congenital heart disease with cardiopulmonary bypass between July 2010 and July 2012 were included in the study. Neonates age<1 month were excluded from the study population. INTERVENTIONS: The association between uAlb and occurrence of AKI within 3 days after admission to the intensive care unit was investigated. Criteria from pediatric-modified Risk Injury Failure Loss and End-stage kidney disease (pRIFLE) were used to determine the occurrence of AKI. The value of uAlb was measured at intensive care unit admission immediately after cardiac surgery in all participants from whom a 5-mL urine sample was obtained. MEASUREMENTS AND MAIN RESULTS: Of 376 patients, AKI assessed by pRIFLE was identified in 243 (64.6%): 172 for risk (R; 45.7%), 44 for injury (I; 11.7%), and 27 for failure (F; 7.2%). One hundred thirty-three patients (35.4%) were classified as being without AKI (normal [N]) by pRIFLE. The concentration of uAlb was significantly higher in AKI patients than in non-AKI patients (median [interquartile range]): uAlb (µg/mL): 13.5 (6.4-39.6) v 6.0 (3.4-16), p<0.001; uAlb/Cr (mg/gCr): 325 (138-760) v 121 (53-269), p< 0.001. CONCLUSIONS: The utility of uAlb for prompt diagnosis of AKI was shown. Obtaining uAlb measurements early after pediatric cardiac surgery may be useful for predicting the occurrence and severity of AKI.

The urinary levels of prostanoid metabolites predict acute kidney injury in heterogeneous adult Japanese ICU patients: a prospective observational study.

BACKGROUND: Acute kidney injury (AKI) is frequently observed in critically ill patients in the intensive care unit (ICU) and is associated with increased mortality. Prostanoids regulate numerous biological functions, including hemodynamics and renal tubular transport. We herein investigated the ability of urinary prostanoid metabolites to predict the onset of AKI in critically ill adult patients. METHODS: The current study was conducted as a prospective observational study. Urine of patients admitted to the ICU at Okayama University Hospital was collected and the urinary levels of prostaglandin E2 (PGE2), PGI2 metabolite (2,3-dinor-6-OXO-PGF1α), thromboxane A2 (TXA2) metabolite (11-dehydro-TXB2) were determined. RESULTS: Of the 93 patients, 24 developed AKI (AKIN criteria). Surgical intervention (93, 75 %) was the leading cause of ICU admission. Overall, the ratio of the level of serum Cr on Day 1 after ICU admission to that observed at baseline positively correlated with the urinary 2,3-dinor-6-OXO-PGF1α/Cr (r = 0.57, p < 0.0001) and 11-dehydro-TXB2/Cr (r = 0.47, p < 0.0001) ratios. In 16 cases of de novo AKI, the urinary 2,3-dinor-6-OXO-PGF1α/Cr and 11-dehydro-TXB2/Cr values were significantly elevated compared with that observed in the non-AKI group, whereas the urinary PGE2/Cr values were not. The urinary 2,3-dinor-6-OXO-PGF1α/Cr ratio exhibited the best diagnostic and predictive performance among the prostanoid metabolites according to the receiver operating characteristic (ROC) analysis [ROC-area under the curve (AUC): 0.75]. CONCLUSIONS: Taken together, these results demonstrate that the urinary 2,3-dinor-6-OXO-PGF1α/Cr and 11-dehydro-TXB2/Cr ratios are associated with the subsequent onset of AKI and poor outcomes in adult heterogeneous ICU patients.

ONO-1301, a sustained-release prostacyclin analog, ameliorates the renal alterations in a mouse type 2 diabetes model possibly through its protective effects on mesangial cells.

Diabetic nephropathy is the most common pathological disorder predisposing patients to end-stage renal disease. Considering the increasing prevalence of type 2 diabetes mellitus worldwide, novel therapeutic approaches are urgently needed. ONO-1301 is a novel sustained-release prostacyclin analog that inhibits thromboxane A2 synthase. Here we examined the therapeutic effects of the intermittent administration of slow-release ONO-1301 (SR-ONO) on diabetic nephropathy in obese type 2 diabetes mice, as well as its direct effects on mesangial cells. The subcutaneous injection of SR-ONO (3mg/kg) every 3 wks did not affect the obesity or hyperglycemia in the db/db obese mice used as a model of type 2 diabetes, but it significantly ameliorated their albuminuria, glomerular hypertrophy, glomerular accumulation of type IV collagen, and monocyte/macrophage infiltration, and also the increase of TGF-ß1, α-smooth muscle actin (α-SMA) and MCP-1 compared to vehicle treatment. In cultured mouse mesangial cells, ONO-1301 concentration-dependently suppressed the increases in TGF-ß, type IV collagen, α-SMA, MCP-1 and fibronectin induced by high ambient glucose, at least partly through prostacyclin (PGI2) receptor-mediated signaling. Taken together, these results suggest the potential therapeutic efficacy of the intermittent administration of SR-ONO against type 2 diabetic nephropathy, possibly through protective effects on mesangial cells.

Upstream stimulatory factors 1 and 2 mediate the transcription of angiotensin II binding and inhibitory protein.

The angiotensin II type 1 receptor (AT1R)-associated protein (ATRAP/Agtrap) promotes constitutive internalization of the AT1R so as to specifically inhibit the pathological activation of its downstream signaling yet preserve the base-line physiological signaling activity of the AT1R. Thus, tissue-specific regulation of Agtrap expression is relevant to the pathophysiology of cardiovascular and renal disease. However, the regulatory mechanism of Agtrap gene expression has not yet been fully elucidated. In this study, we show that the proximal promoter region from -150 to +72 of the mouse Agtrap promoter, which contains the X-box, E-box, and GC-box consensus motifs, is able to elicit substantial transcription of the Agtrap gene. Among these binding motifs, we showed that the E-box specifically binds upstream stimulatory factor (Usf) 1 and Usf2, which are known E-box-binding transcription factors. It is indicated that the E-box-Usf1/Usf2 binding regulates Agtrap expression because of the following: 1) mutation of the E-box to prevent Usf1/Usf2 binding reduces Agtrap promoter activity; 2) knockdown of Usf1 or Usf2 affects both endogenous Agtrap mRNA and Agtrap protein expression, and 3) the decrease in Agtrap mRNA expression in the afflicted kidney by unilateral ureteral obstruction is accompanied by changes in Usf1 and Usf2 mRNA. Furthermore, the results of siRNA transfection in mouse distal convoluted tubule cells and those of unilateral ureteral obstruction in the afflicted mouse kidney suggest that Usf1 decreases but Usf2 increases the Agtrap gene expression by binding to the E-box. The results also demonstrate a functional E-box-USF1/USF2 interaction in the human AGTRAP promoter, thereby suggesting that a strategy of modulating the E-box-USF1/USF2 binding has novel therapeutic potential.

Renal distribution of Vasohibin-1 in patients with chronic kidney disease.

Experimental studies have demonstrated the involvement of angiogenesis-related factors in the progression of chronic kidney disease (CKD). There have so far been no reports investigating the distribution and clinical roles of Vasohibin-1 (VASH-1), a negative feedback regulator of angiogenesis, in CKD. We recruited 54 Japanese CKD patients and 6 patients who had normal renal tissues excised due to localized renal cell carcinoma. We evaluated the correlations between the renal expression level of VASH-1 and the clinical/histological parameters. VASH-1 was observed in renal endothelial/mesangial cells, crescentic lesions and interstitial inflammatory cells. Significant positive correlations were observed between 1) crescent formation and the number of VASH-1+ cells in the glomerulus (r＝0.48, p＝0.001) or cortex (r＝0.64, p＜0.0001), 2) interstitial cell infiltration and the number of VASH-1+ cells in the cortex (r＝0.34, p＝0.02), 3) the glomerular VEGFR-2+ area and the number of VASH-1+ cells in the glomerulus (r＝0.44, p＝0.01) or medulla (r＝0.63, p＝0.01). These results suggest that the renal levels of VASH-1 may be affected by local inflammation, crescentic lesions and VEGFR-2.

The Effect of Medical Cooperation in the CKD Patients: 10-Year Multicenter Cohort Study.

INTRODUCTION: While chronic kidney disease (CKD) is one of the most important contributors to mortality from non-communicable diseases, the number of nephrologists is limited worldwide. Medical cooperation is a system of cooperation between primary care physicians and nephrological institutions, consisting of nephrologists and multidisciplinary care teams. Although it has been reported that multidisciplinary care teams contribute to the prevention of worsening renal functions and cardiovascular events, there are few studies on the effect of a medical cooperation system. METHODS: We aimed to evaluate the effect of medical cooperation on all-cause mortality and renal prognosis in patients with CKD. One hundred and sixty-eight patients who visited the one hundred and sixty-three clinics and seven general hospitals of Okayama city were recruited between December 2009 and September 2016, and one hundred twenty-three patients were classified into a medical cooperation group. The outcome was defined as the incidence of all-cause mortality, or renal composite outcome (end-stage renal disease or 50% eGFR decline). We evaluated the effects on renal composite outcome and pre-ESRD mortality while incorporating the competing risk for the alternate outcome into a Fine-Gray subdistribution hazard model. RESULTS: The medical cooperation group had more patients with glomerulonephritis (35.0% vs. 2.2%) and less nephrosclerosis (35.0% vs. 64.5%) than the primary care group. Throughout the follow-up period of 5.59 ± 2.78 years, 23 participants (13.7%) died, 41 participants (24.4%) reached 50% decline in eGFR, and 37 participants (22.0%) developed end-stage renal disease (ESRD). All-cause mortality was significantly reduced by medical cooperation (sHR 0.297, 95% CI 0.105-0.835, p = 0.021). However, there was a significant association between medical cooperation and CKD progression (sHR 3.069, 95% CI 1.225-7.687, p = 0.017). CONCLUSION: We evaluated mortality and ESRD using a CKD cohort with a long-term observation period and concluded that medical cooperation might be expected to influence the quality of medical care in the patients with CKD.

Sustained-release prostacyclin analog ONO-1301 ameliorates tubulointerstitial alterations in a mouse obstructive nephropathy model.

Tubulointerstitial injuries are crucial histological alterations that predict the deterioration of renal function in chronic kidney disease. ONO-1301, a novel sustained-release prostacyclin analog, accompanied by thromboxane synthase activity, exerts therapeutic effects on experimental pulmonary hypertension, lung fibrosis, cardiomyopathy, and myocardial ischemia, partly associated with the induction of hepatocyte growth factor (HGF). In the present study, we examined the therapeutic efficacies of ONO-1301 on tubulointerstitial alterations induced by unilateral ureteral obstruction (UUO). After inducing unilateral ureteral obstruction in C57/BL6J mice, a single injection of sustained-release ONO-1301 polymerized with poly (D,L-lactic-co-glycolic acid) sustained-release ONO-1301 (SR-ONO) significantly suppressed interstitial fibrosis, accumulation of types I and III collagen, increase in the number of interstitial fibroblast-specific protein-1 (FSP-1)(+) cells, and interstitial infiltration of monocytes/macrophages (F4/80(+)) in the obstructed kidneys (OBK; day 7). Treatment with SR-ONO significantly suppressed the increase of the renal levels of profibrotic factor TGF-ß and phosphorylation of Smad2/3, and elevated the renal levels of HGF in the OBK. In cultured mouse proximal tubular epithelial cells (mProx24), ONO-1301 significantly ameliorated the expression of fibroblast-specific protein-1 and α-smooth muscle actin as well as phosphorylation of Smad3 and increased the expression of zonula occludens-1 and E-cadherin in the presence of TGF-ß1 as detected by immunoblot and immunocytochemistry, partly dependent on PGI(2) receptor-mediated signaling. Administration of rabbit anti-HGF antibodies, but not the control IgG, partly reversed the suppressive effects of SR-ONO on tubulointerstitial injuries in the OBK. Taken together, our findings suggest the potential therapeutic efficacies of ONO-1301 in suppressing tubulointerstitial alterations partly mediated via inducing HGF, an antifibrotic factor counteracting TGF-ß.

Epicatechin limits renal injury by mitochondrial protection in cisplatin nephropathy.

Cisplatin nephropathy can be regarded as a mitochondrial disease. Intervention to halt such deleterious injury is under investigation. Recently, the flavanol (-)-epicatechin emerges as a novel compound to protect the cardiovascular system, owing in part to mitochondrial protection. Here, we have hypothesized that epicatechin prevents the progression of cisplatin-induced kidney injury by protecting mitochondria. Epicatechin was administered 8 h after cisplatin injury was induced in the mouse kidney. Cisplatin significantly induced renal dysfunction and tubular injury along with an increase in oxidative stress. Mitochondrial damages were also evident as a decrease in loss of mitochondrial mass with a reduction in the oxidative phosphorylation complexes and low levels of MnSOD. The renal damages and mitochondrial injuries were significantly prevented by epicatechin treatment. Consistent with these observations, an in vitro study using cultured mouse proximal tubular cells demonstrated that cisplatin-induced mitochondrial injury, as revealed by a decrease in mitochondrial succinate dehydrogenase activity, an induction of cytochrome c release, mitochondrial fragmentation, and a reduction in complex IV protein, was prevented by epicatechin. Such a protective effect of epicatechin might be attributed to decreased oxidative stress and reduced ERK activity. Finally, we confirmed that epicatechin did not perturb the anticancer effect of cisplatin in HeLa cells. In conclusion, epicatechin exhibits protective effects due in part to its ability to prevent the progression of mitochondrial injury in mouse cisplatin nephropathy. Epicatechin may be a novel option to treat renal disorders associated with mitochondrial dysfunction.

Physiological levels of tumstatin, a fragment of collagen IV alpha3 chain, are generated by MMP-9 proteolysis and suppress angiogenesis via alphaV beta3 integrin.

We demonstrate a physiological role for tumstatin, a cleavage fragment of the alpha3 chain of type IV collagen (Col IValpha3), which is present in the circulation. Mice with a genetic deletion of Col IValpha3 show accelerated tumor growth associated with enhanced pathological angiogenesis, while angiogenesis associated with development and tissue repair are unaffected. Supplementing Col IValpha3-deficient mice with recombinant tumstatin to a normal physiological concentration abolishes the increased rate of tumor growth. The suppressive effects of tumstatin require alphaVbeta3 integrin expressed on pathological, but not on physiological, angiogenic blood vessels. Mice deficient in matrix metalloproteinase-9, which cleaves tumstatin efficiently from Col IValpha3, have decreased circulating tumstatin and accelerated growth of tumor. These results indicate that MMP-generated fragments of basement membrane collagen can have endogenous function as integrin-mediated suppressors of pathologic angiogenesis and tumor growth.

A case of focal segmental glomerulosclerosis in an adult patient with hypogammaglobulinemia superimposed on membranoproliferative glomerulonephritis in childhood.

BACKGROUND: Common variable immunodeficiency (CVID) is a disorder characterized by hypogammaglobulinemia without a known predisposing cause. CASE PRESENTATION: We report a 36-year-old man who had suffered membranoproliferative glomerulonephritis (MPGN) in his childhood, later diagnosed with CVID at 35 years of age. He presented at our hospital with signs of proteinuria. A renal biopsy revealed he suffered from focal segmental glomerulosclerosis (FSGS), possibly due to obesity and hypertension, not CVID - associated MPGN. CONCLUSION: This is the first case report of FSGS in a CVID patient. In this case, we have to pay attention not only to the treatment of obesity and hypertension for FSGS but also to the recurrence of immune-complex glomerulonephritis such as MPGN, in case of the restoration of hypogammaglobulinemia.

Acatalasemic mice are mildly susceptible to adriamycin nephropathy and exhibit increased albuminuria and glomerulosclerosis.

BACKGROUND: Catalase is an important antioxidant enzyme that regulates the level of intracellular hydrogen peroxide and hydroxyl radicals. The effects of catalase deficiency on albuminuria and progressive glomerulosclerosis have not yet been fully elucidated. The adriamycin (ADR) nephropathy model is considered to be an experimental model of focal segmental glomerulosclerosis. A functional catalase deficiency was hypothesized to exacerbate albuminuria and the progression of glomerulosclerosis in this model. METHODS: ADR was intravenously administered to both homozygous acatalasemic mutant mice (C3H/AnLCs(b)Cs(b)) and control wild-type mice (C3H/AnLCs(a)Cs(a)). The functional and morphological alterations of the kidneys, including albuminuria, renal function, podocytic, glomerular and tubulointerstitial injuries, and the activities of catalase were then compared between the two groups up to 8 weeks after disease induction. Moreover, the presence of a mutation of the toll-like receptor 4 (tlr4) gene, which was previously reported in the C3H/HeJ strain, was investigated in both groups. RESULTS: The ADR-treated mice developed significant albuminuria and glomerulosclerosis, and the degree of these conditions in the ADR-treated acatalasemic mice was higher than that in the wild-type mice. ADR induced progressive renal fibrosis, renal atrophy and lipid peroxide accumulation only in the acatalasemic mice. In addition, the level of catalase activity was significantly lower in the kidneys of the acatalasemic mice than in the wild-type mice during the experimental period. The catalase activity increased after ADR injection in wild-type mice, but the acatalasemic mice did not have the ability to increase their catalase activity under oxidative stress. The C3H/AnL strain was found to be negative for the tlr4 gene mutation. CONCLUSIONS: These data indicate that catalase deficiency plays an important role in the progression of renal injury in the ADR nephropathy model.

Involvement of Runx3 in the basal transcriptional activation of the mouse angiotensin II type 1 receptor-associated protein gene.

We previously cloned a molecule that interacts with angiotensin II type 1 (AT1) receptor to exert an inhibitory function on AT1 receptor signaling that we named ATRAP/Agtrap (for AT1 receptor-associated protein). In the present study we examined the regulation of basal ATRAP gene expression using renal distal convoluted tubule cells. We found that serum starvation upregulated basal expression of ATRAP gene, a response that required de novo mRNA and protein synthesis. Luciferase assay revealed that the proximal promoter region directs transcription and that a putative binding site of runt-related transcription factors (RBE) is important for transcriptional activation. The results of RBE-decoy transfection and endogenous knockdown by small interference RNA showed that the runt-related transcription factor Runx3 is involved in ATRAP gene expression. Chromatin immunoprecipitation assay also supported the binding of Runx3 to the ATRAP promoter in renal distal convoluted tubule cells. Immunohistochemistry demonstrated the expression of Runx3 and ATRAP proteins in the distal convoluted and connecting tubules of the kidney in consecutive sections. Furthermore, the Runx3 immunostaining was decreased together with a concomitant suppression of ATRAP expression in the affected kidney after 7 days of unilateral ureteral obstruction. These findings indicate that Runx3 plays a role in ATRAP gene expression in renal distal tubular cells both in vitro and in vivo.

Sensitization to alloxan-induced diabetes and pancreatic cell apoptosis in acatalasemic mice.

Human acatalasemia may be a risk factor for the development of diabetes mellitus. However, the mechanism by which diabetes is induced is still poorly understood. The impact of catalase deficiency on the onset of diabetes has been studied in homozygous acatalasemic mutant mice or control wild-type mice by intraperitoneal injection of diabetogenic alloxan. The incidence of diabetes was higher in acatalasemic mice treated with a high dose (180 mg/kg body weight) of alloxan. A higher dose of alloxan accelerated severe atrophy of pancreatic islets and induced pancreatic beta cell apoptosis in acatalasemic mice in comparison to wild-type mice. Catalase activity remained low in the acatalasemic pancreas without the significant compensatory up-regulation of glutathione peroxidase or superoxide dismutase. Furthermore, daily intraperitoneal injection of angiotensin II type 1 (AT1) receptor antagonist telmisartan (0.1 mg/kg body weight) prevented the development of alloxan-induced hyperglycemia in acatalasemic mice. This study suggests that catalase plays a crucial role in the defense against oxidative-stress-mediated pancreatic beta cell death in an alloxan-induced diabetes mouse model. Treatment with telmisartan may prevent the onset of alloxan-induced diabetes even under acatalasemic conditions.

Amelioration of renal alterations in obese type 2 diabetic mice by vasohibin-1, a negative feedback regulator of angiogenesis.

The involvement of VEGF-A as well as the therapeutic efficacy of angiogenesis inhibitors in diabetic nephropathy have been reported. We recently reported the therapeutic effects of vasohibin-1 (VASH-1), an endogenous angiogenesis inhibitor, in a type 1 diabetic nephropathy model (Nasu T, Maeshima Y, Kinomura M, Hirokoshi-Kawahara K, Tanabe K, Sugiyama H, Sonoda H, Sato Y, Makino H. Diabetes 58: 2365-2375, 2009). In this study, we investigated the therapeutic efficacy of VASH-1 on renal alterations in obese mice with type 2 diabetes. Diabetic db/db mice received intravenous injections of adenoviral vectors encoding human VASH-1 (AdhVASH-1) and were euthanized 8 wk later. AdhVASH-1 treatment resulted in significant suppression of glomerular hypertrophy, glomerular hyperfiltration, albuminuria, increase in the CD31(+) glomerular endothelial area, F4/80(+) monocyte/macrophage infiltration, the accumulation of type IV collagen, and mesangial matrix. An increase in the renal levels of VEGF-A, VEGFR-2, transforming growth factor (TGF)-ß1, and monocyte chemoattractant protein-1 in diabetic animals was significantly suppressed by AdhVASH-1 (immunoblotting). AdhVASH-1 treatment significantly recovered the loss and altered the distribution patterns of nephrin and zonula occludens (ZO)-1 and suppressed the increase in the number of fibroblast-specific protein-1 (FSP-1(+)) and desmin(+) podocytes in diabetic mice. In vitro, recombinant human VASH-1 (rhVASH-1) dose dependently suppressed the upregulation of VEGF induced by high ambient glucose (25 mM) in cultured mouse podocytes. In addition, rhVASH-1 significantly recovered the mRNA levels of nephrin and the protein levels of ZO-1 and P-cadherin and suppressed the increase in protein levels of desmin, FSP-1, Snail, and Slug in podocytes under high-glucose condition. Taken together, these results suggest the potential use of VASH-1 as a novel therapeutic agent in type 2 diabetic nephropathy mediated via antiangiogenic effects and maintenance of podocyte phenotype in association with antiproteinuric effects.

Identification of amino acids essential for the antiangiogenic activity of tumstatin and its use in combination antitumor activity.

Tumstatin is an angiogenesis inhibitor that binds to alphavbeta3 integrin and suppresses tumor growth. Previous deletion mutagenesis studies identified a 25-aa fragment of tumstatin (tumstatin peptide) with in vitro antiangiogenic activity. Here, we demonstrate that systemic administration of this tumstatin peptide inhibits tumor growth and angiogenesis. Site-directed mutagenesis identified amino acids L, V, and D as essential for the antiangiogenic activity of tumstatin. The tumstatin peptide binds to alphavbeta3 integrin on proliferating endothelial cells and localizes to select tumor endothelium in vivo. Using 3D molecular modeling, we identify a putative interaction interface for tumstatin peptide on alphavbeta3 integrin. The antitumor activity of the tumstatin peptide, in combination with bevacizumab (anti-VEGF antibody), displays significant improvement in efficacy against human renal cell carcinoma xenografts when compared with the single-agent use. Collectively, our results demonstrate that tumstatin peptide binds specifically to the tumor endothelium, and its antiangiogenic action is mediated by alphavbeta3 integrin, and, in combination with an anti-VEGF antibody it exhibits enhanced tumor suppression of renal cell carcinoma.

Association of blood pressure and renal outcome in patients with chronic kidney disease; a post hoc analysis of FROM-J study.

It is well-known that hypertension exacerbates chronic kidney disease (CKD) progression, however, the optimal target blood pressure (BP) level in patients with CKD remains unclear. This study aimed to assess the optimal BP level for preventing CKD progression. The risk of renal outcome among different BP categories at baseline as well as 1 year after, were evaluated using individual CKD patient data aged between 40 and 74 years from FROM-J [Frontier of Renal Outcome Modifications in Japan] study. The renal outcome was defined as ≥ 40% reduction in estimated glomerular filtration rate to < 60 mL/min/1.73 m2, or a diagnosis of end stage renal disease. Regarding baseline BP, the group of systolic BP (SBP) 120-129 mmHg had the lowest risk of the renal outcome, which increased more than 60% in SBP ≥ 130 mmHg group. A significant increase in the renal outcome was found only in the group of diastolic BP ≥ 90 mmHg. The group of BP < 130/80 mmHg had a benefit for lowering the risk regardless of the presence of proteinuria, and it significantly reduced the risk in patients with proteinuria. Achieving SBP level < 130 mmHg after one year resulted in a 42% risk reduction in patients with SBP level ≥ 130 mmHg at baseline. Targeting SBP level < 130 mmHg would be associated with the preferable renal outcome.Clinical Trial Registration-URL: https://www.umin.ac.jp/ctr/ . Unique identifier: UMIN000001159 (16/05/2008).

Differential expression of glycogenes in tonsillar B lymphocytes in association with proteinuria and renal dysfunction in IgA nephropathy.

Aberrant O-glycosylation of serum and tonsillar IgA1 is one of the main pathogeneses of IgA nephropathy (IgAN). However, the synthesis of underglycosylated IgA1 in tonsils has not yet been characterized. This study examined tonsillar B lymphocytes of IgAN (n=34) using tonsils derived from patients with chronic tonsillitis (n=24) and sleep apnea syndrome (n=14) as a control. Gene expression of beta1,3-galactosyltransferase (beta3GalT), and the core 1 beta3GalT-specific molecular chaperone, Cosmc, UDP-N-acetyl-alpha-D-galactosamine: polypeptide N-acetylgalactosaminyl-transferase 2, were significantly decreased in tonsillar CD19-positive B lymphocytes from IgAN patients compared to control tonsillar tissues as determined by real-time RT-PCR. Tonsillar B cell beta3GalT gene expression significantly correlated with estimated GFR and negatively correlated with proteinuria and histological injury score. Western blotting showed the protein expression of beta3GalT in the tonsils to significantly decrease in IgAN in comparison to the controls. These data suggest the downregulation of beta3GalT in tonsillar B lymphocytes to be closely associated with the clinical characteristics of IgAN.