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.

Deletion of pro-angiogenic factor vasohibin-2 ameliorates glomerular alterations in a mouse diabetic nephropathy model.

Angiogenesis has been implicated in glomerular alterations in the early stage of diabetic nephropathy. We previously reported the renoprotective effects of vasohibin-1 (VASH1), which is a novel angiogenesis inhibitor derived from endothelial cells, on diabetic nephropathy progression. Vasohibin-2 (VASH2) was originally identified as a VASH1 homolog and possesses pro-angiogenic activity in contrast to VASH1. In addition, VASH2 was recently shown to promote epithelial-to-mesenchymal transition via enhanced transforming growth factor (TGF)-ß signaling in cancer cells. Herein, we investigated the pathogenic roles of VASH2 in diabetic nephropathy using VAHS2-deficient mice. The type 1 diabetes model was induced by intraperitoneal injections of streptozotocin in VASH2 homozygous knockout (VASH2LacZ/LacZ) or wild-type mice. These mice were euthanized 16 weeks after inducing hyperglycemia. Increased urine albumin excretion and creatinine clearance observed in diabetic wild-type mice were significantly prevented in diabetic VASH2-deficient mice. Accordingly, diabetes-induced increase in glomerular volume and reduction in glomerular slit-diaphragm density were significantly improved in VASH2 knockout mice. Increased glomerular endothelial area was also suppressed in VASH2-deficient mice, in association with inhibition of enhanced vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2), but not VEGF level. Furthermore, glomerular accumulation of mesangial matrix, including type IV collagen, and increased expression of TGF-ß were improved in diabetic VASH2 knockout mice compared with diabetic wild-type mice. Based on the immunofluorescence findings, endogenous VASH2 localization in glomeruli was consistent with mesangial cells. Human mesangial cells (HMCs) were cultured under high glucose condition in in vitro experiments. Transfection of VASH2 small interfering RNA (siRNA) into the HMCs resulted in the suppression of type IV collagen production induced by high glucose compared with control siRNA. These results indicate that VASH2 may be involved in diabetes-induced glomerular alterations, particularly impaired filtration barrier and mesangial expansion. Therefore, VASH2 is likely to represent a promising therapeutic target for diabetic nephropathy.

Development of a novel estimation method for hemoglobin A1c using glycated albumin in type 2 diabetes mellitus patients with end-stage renal disease.

AIM: We developed a novel estimation method for hemoglobin A1c (HbA1c) in type 2 diabetes (T2D) patients with end-stage renal disease (ESRD). This method is based on the glycated albumin (GA) level. METHODS: Of the 788 Japanese patients with T2D included in this study, 545 had normal renal function (NRF group) and 243 had ESRD. Oral glucose tolerance tests (OGTTs) were performed in 80 subjects. The variables GA, body mass index (BMI), hemoglobin (Hb), and estimated glomerular filtration rate (eGFR) were significantly associated with the GA-to-HbA1c ratio and were used to determine the estimated HbA1c (eHbA1c). One method of estimating HbA1c involved dividing GA by the GA-to-HbA1c ratio predicted from the estimated regression equation; the estimated HbA1c obtained in this manner was denoted eHbA1c-1. RESULTS: eHbA1c-1 (%) = GA × [4.688 - 18.833 × GA-1 - 0.015 × BMI - 0.037 × Hb (- 0.002 × eGFR for patients without ESRD)]-1; adjusted R 2 = 0.676 for actual HbA1c. The sensitivity of eHbA1c-1 was better than that of GA for diabetes diagnosis using the 75-g OGTT. There were no differences in the slope of eHbA1c-1 versus GA and the variance of eHbA1c-1 between the ESRD and NRF groups. eHbA1c-1 was not associated with Hb, erythropoiesis-stimulating agent use, or ESRD concomitance. CONCLUSIONS: eHbA1c-1 may be a useful parameter for estimating HbA1c in T2D patients with ESRD.

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.

Exacerbation of diabetic renal alterations in mice lacking vasohibin-1.

Vasohibin-1 (VASH1) is a unique endogenous inhibitor of angiogenesis that is induced in endothelial cells by pro-angiogenic factors. We previously reported renoprotective effect of adenoviral delivery of VASH1 in diabetic nephropathy model, and herein investigated the potential protective role of endogenous VASH1 by using VASH1-deficient mice. Streptozotocin-induced type 1 diabetic VASH1 heterozygous knockout mice (VASH1(+/-)) or wild-type diabetic mice were sacrificed 16 weeks after inducing diabetes. In the diabetic VASH1(+/-) mice, albuminuria were significantly exacerbated compared with the diabetic wild-type littermates, in association with the dysregulated distribution of glomerular slit diaphragm related proteins, nephrin and ZO-1, glomerular basement membrane thickening and reduction of slit diaphragm density. Glomerular monocyte/macrophage infiltration and glomerular nuclear translocation of phosphorylated NF-κB p65 were significantly exacerbated in the diabetic VASH1(+/-) mice compared with the diabetic wild-type littermates, accompanied by the augmentation of VEGF-A, M1 macrophage-derived MCP-1 and phosphorylation of IκBα, and the decrease of angiopoietin-1/2 ratio and M2 macrophage-derived Arginase-1. The glomerular CD31(+) endothelial area was also increased in the diabetic VASH1(+/-) mice compared with the diabetic-wild type littermates. Furthermore, the renal and glomerular hypertrophy, glomerular accumulation of mesangial matrix and type IV collagen and activation of renal TGF-ß1/Smad3 signaling, a key mediator of renal fibrosis, were exacerbated in the diabetic VASH1(+/-) mice compared with the diabetic wild-type littermates. In conditionally immortalized mouse podocytes cultured under high glucose condition, transfection of VASH1 small interfering RNA (siRNA) resulted in the reduction of nephrin, angiopoietin-1 and ZO-1, and the augmentation of VEGF-A compared with control siRNA. These results suggest that endogenous VASH1 may regulate the development of diabetic renal alterations, partly via direct effects on podocytes, and thus, a strategy to recover VASH1 might potentially lead to the development of a novel therapeutic approach for diabetic nephropathy.

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.

Urinary and plasma levels of vasohibin-1 can predict renal functional deterioration in patients with renal disorders.

Vasohibin-1 (VASH-1) is a negative feedback regulator of angiogenesis, and a small vasohibin-binding protein (SVBP) serves as its secretory chaperone and contributes to its antiangiogenic effects. In the present study, we aimed to define the clinical significance of VASH-1 and SVBP in patients with chronic kidney disease (CKD). We recruited 67 Japanese hospitalized patients with renal disorders with (n = 45) or without (n = 22) renal biopsy samples and 10 Japanese healthy controls. We evaluated the correlations between the plasma and urinary levels of VASH-1/VASH-1-SVBP complex/SVBP and the clinicopathological parameters. The plasma levels of VASH-1 were inversely correlated with age and systolic and diastolic blood pressure and positively correlated with crescent formation. Increased plasma and urinary levels of VASH-1 and VASH-1-SVBP complex were significantly correlated with worse renal outcomes. These results demonstrate an association between elevated urinary and plasma levels of VASH-1 and progressive decline of the renal function, thus suggesting a potential role for VASH-1 in predicting a worse renal prognosis in patients with renal disease, including CKD.

Vasohibin-1 deficiency enhances renal fibrosis and inflammation after unilateral ureteral obstruction.

Tubulointerstitial injuries are known to predict the deterioration of renal function in chronic kidney disease (CKD). We recently reported the protective role of Vasohibin-1(VASH-1), a negative feedback regulator of angiogenesis, in diabetic nephropathy, but its impact on tubulointerstitial injuries remains to be elucidated. In the present study, we evaluated the role of endogenous VASH-1 in regulating the tubulointerstitial alterations induced by unilateral ureteral obstruction (UUO), and assessed its role on fibrogenesis and the activation of Smad3 signaling in renal fibroblasts. UUO was induced in female Vasohibin-1 heterozygous knockout mice (VASH-1(+/-)) or wild-type (WT) (VASH-1(+/+)) littermates. Mice were sacrificed on Day 7 after left ureter ligation, and the kidney tissue was obtained. Interstitial fibrosis, the accumulation of type I and type III collagen and monocytes/macrophages infiltration in the obstructed kidneys (OBK) were significantly exacerbated in VASH-1(+/-) mice compared with WT mice (Day 7). The increases in the renal levels of TGF-ß1, pSmad3, NF-κB pp65, CCL2 mRNA, and the number of interstitial fibroblast-specific protein-1 (FSP-1)(+) fibroblasts in the OBK were significantly aggravated in VASH-1(+/-) mice. In addition, treatment with VASH-1 siRNA enhanced the TGF-ß1-induced phosphorylation of Smad3, the transcriptional activation of the Smad3 pathway and the production of type I/type III collagen in fibroblasts, in vitro. Taken together, our findings demonstrate a protective role for endogenous VASH-1 on tubulointerstitial alterations via its regulation of inflammation and fibrosis and also show the direct anti-fibrotic effects of VASH-1 on renal fibroblasts through its modulation of TGF-ß1 signaling.

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.