Published papers

© 2019 by the American Diabetes Association. OBJECTIVE To investigate the prevalence and causes of diabetes in patients with primary aldosteronism (PA) in a multi-institutional cohort study in Japan. RESEARCH DESIGN AND METHODS The prevalence of diabetes was determined in 2,210 patients with PA (diagnosed or glycated hemoglobin [HbA1c] ‡6.5% [‡48 mmol/mol]; NGSP) and compared with that of the Japanese general population according to age and sex. In 1,386 patients with PA and clear laterality (unilateral or bilateral), the effects of plasma aldosterone concentration (PAC), hypokalemia (<3.5 mEq/L), suspected subclinical hypercortisolism (SH; serum cortisol ‡1.8 mg/dL after 1-mg dexamethasone suppression test), and PA laterality on the prevalence of diabetes or prediabetes (5.7% £ HbA1c <6.5% [39 mmol/mol £ HbA1c <48 mmol/mol]) were examined. RESULTS Of the 2,210 patients with PA, 477 (21.6%) had diabetes. This prevalence is higher than that in the general population (12.1%) or in 10-year cohorts aged 30–69 years. Logistic regression or x2 test revealed a significant contribution of suspected SH to diabetes. Despite more active PA profiles (e.g., higher PAC and lower potassium concentrations) in unilateral than bilateral PA, BMI and HbA1c values were significantly higher in bilateral PA. PA laterality had no effect on the prevalence of diabetes; however, the prevalence of prediabetes was significantly higher in bilateral than unilateral PA. CONCLUSIONS Individuals with PA have a high prevalence of diabetes, which is associated mainly with SH. The prevalence of prediabetes is greater for bilateral than unilateral PA, suggesting a unique metabolic cause of bilateral PA.

© 2019, The Author(s). Potential effects of aerobic and resistance training in peritoneal dialysis (PD) patients have been partially elucidated. We investigated effects of a home-based exercise program on physical functioning and health-related quality of life (HRQOL) in PD patients. Patients were randomly assigned to exercise (n = 24) and usual care (n = 23) groups. The exercise patients performed aerobic exercise thrice weekly and resistance training twice weekly at home for 12 weeks. The usual care patients received no specific intervention. The distance in incremental shuttle walking test significantly improved in the exercise group compared with the usual care group (P = 0.02). Among the HRQOL subscales assessed using the Kidney Disease Quality of Life-Short Form questionnaire, kidney disease component summary (P = 0.03), physical role functioning (P = 0.01), emotional role functioning (P < 0.01), and role/social component summary (P < 0.01) significantly improved in the exercise group. Moreover, serum albumin was significantly maintained in the exercise group (P = 0.03). There were no reported adverse events associated with the intervention. To our knowledge, this is the first randomized controlled trial to indicate the beneficial effects of a 12-week home-based exercise program exclusively in PD patients.

© 2019, The Author(s). Purpose of Review: Hypertension is related to impaired metabolic homeostasis and can be regarded as a metabolic disorder. This review presents possible mechanisms by which metabolic disorders increase blood pressure (BP) and discusses the importance of the gut as a novel modulator of BP. Recent Findings: Obesity and high salt intake are major risk factors for hypertension. There is a hypothesis of “salt-induced obesity”; i.e., high salt intake may tie to obesity. Heightened sympathetic nervous system (SNS) activity, especially in the kidney and brain, increases BP in obese patients. Adipokines, including adiponectin and leptin, and renin-angiotensin-aldosterone system (RAAS) contribute to hypertension. Adiponectin induced by a high-salt diet may decrease sodium/glucose cotransporter (SGLT) 2 expression in the kidney, which results in reducing BP. High salt can change secretions of adipokines and RAAS-related components. Evidence has been accumulating linking the gastrointestinal tract to BP. Glucagon-like peptide-1 (GLP-1) and ghrelin decrease BP in both rodents and humans. The sweet taste receptor in enteroendocrine cells increases SGLT1 expression and stimulates sodium/glucose absorption. Roux-en-Y gastric bypass improves glycemic and BP control due to reducing the activity of SGLT1. Na/H exchanger isoform 3 (NHE3) increases BP by stimulating the intestinal absorption of sodium. Gastrin functions as an intestinal sodium taste sensor and inhibits NHE3 activity. Intestinal mineralocorticoid receptors also regulate sodium absorption and BP due to changing ENaC activity. Gastric sensing of sodium induces natriuresis, and gastric distension increases BP. Changes in the composition and function of gut microbiota contribute to hypertension. A high-salt/fat diet may disrupt the gut barrier, which results in systemic inflammation, insulin resistance, and increased BP. Gut microbiota regulates BP by secreting vasoactive hormones and short-chain fatty acids. BP-lowering effects of probiotics and antibiotics have been reported. Bariatric surgery improves metabolic disorders and hypertension due to increasing GLP-1 secretion, decreasing leptin secretion and SNS activity, and changing gut microbiome composition. Strategies targeting the gastrointestinal system may be therapeutic options for improving metabolic abnormalities and reducing BP in humans. Summary: SNS, brain, adipocytes, RAAS, the kidney, the gastrointestinal tract, and microbiota play important roles in regulating BP. Most notably, the gut could be a novel target for treatment of hypertension as a metabolic disorder.

© 2019, The Author(s). The derivation of kidney tissues from human pluripotent stem cells (hPSCs) and its application for replacement therapy in end-stage renal disease have been widely discussed. Here we report that consecutive transfections of two sets of synthetic mRNAs encoding transcription factors can induce rapid and efficient differentiation of hPSCs into kidney tissues, termed induced nephron-like organoids (iNephLOs). The first set - FIGLA, PITX2, ASCL1 and TFAP2C, differentiated hPSCs into SIX2 + SALL1 + nephron progenitor cells with 92% efficiency within 2 days. Subsequently, the second set - HNF1A, GATA3, GATA1 and EMX2, differentiated these cells into PAX8 + LHX1 + pretubular aggregates in another 2 days. Further culture in both 2-dimensional and 3-dimensional conditions produced iNephLOs containing cells characterized as podocytes, proximal tubules, and distal tubules in an additional 10 days. Global gene expression profiles showed similarities between iNephLOs and the human adult kidney, suggesting possible uses of iNephLOs as in vitro models for kidneys.

© 2019 Wolters Kluwer Health, Inc. All rights reserved. Objectives:Because of the influence on the renin-angiotensin-aldosterone system, it is recommended to avoid, if possible, the use of angiotensin-converting-enzyme inhibitors, angiotensin II type 1 receptor blockers, diuretics, β-blockers, and mineralocorticoid receptor antagonists during the diagnostic period of primary aldosteronism. A laterality index more than 4 in adrenocorticotropic hormone (ACTH)-stimulated adrenal venous sampling (ACTH-AVS) is a widely used classification of the unilateral subtype that can benefit from adrenalectomy. Here, we revealed clinical features of patients taking drugs that could affect the primary aldosteronism diagnosis (DAPD) and investigated whether the classification with laterality index more than 4 in ACTH-AVS is applicable to these patients.Patients and methods:Using a large database of primary aldosteronism patients in Japan, we analyzed 2122 patients with successful ACTH-AVS.Results:Patients who received any DAPD (n = 209) showed higher prevalence of comorbidity burdens and took more antihypertensive drugs compared with patients without DAPD. In patients taking DAPD, those with laterality index more than 4 had a higher prevalence of hypokalemia, a higher aldosterone-to-renin ratio and a higher prevalence of adrenal mass than those with laterality index of 4 or less. Adrenalectomy was performed in 76% patients with laterality index more than 4 and 20% with laterality index of 4 or less. Patients who underwent adrenalectomy showed biochemical cure in 89% with laterality index more than 4 and 50% with laterality index of 4 or less (P = 0.001). Multivariate regression analysis showed that laterality index more than 4 was an independent predictor of a biochemical cure. Biochemical cure rate in patients with laterality index more than 4 was consistently high, irrespective of the potential effect of individual DAPD on laterality index.Conclusion:Our findings suggest that in primary aldosteronism patients to whom DAPD were administrated due to severe clinical features, laterality index more than 4 in ACTH-AVS could accurately predict a biochemical cure after adrenalectomy.

© 2018 by the American Diabetes Association. OBJECTIVE Diabetes is associated with high risk of cardiovascular (CV) events, particularly in patients with dyslipidemia and diabetic complications. We investigated the incidence of CV events with intensive or standard lipid-lowering therapy in patients with hypercholesterolemia, diabetic retinopathy, and no history of coronary artery disease (treat-to-target approach). RESEARCH DESIGN AND METHODS In this multicenter, prospective, randomized, open-label, blinded end point study, eligible patients were randomly assigned (1:1) to intensive statin therapy targeting LDL cholesterol (LDL-C) <70 mg/dL (n = 2,518) or standard statin therapy targeting LDL-C 100-120 mg/dL (n = 2,524). RESULTS Mean follow-up was 37± 13months. LDL-C at 36 months was 76.5± 21.6mg/dL in the intensive group and 104.1 ± 22.1 mg/dL in the standard group (P < 0.001). The primary end point events occurred in 129 intensive group patients and 153 standard group patients (hazard ratio [HR] 0.84 [95% CI 0.67-1.07]; P = 0.15). The relationship between the LDL-C difference in the two groups and the event reduction rate was consistent with primary prevention studies in patients with diabetes. Exploratory findings showed significantly fewer cerebral events in the intensive group (HR 0.52 [95% CI 0.31-0.88]; P = 0.01). Safety did not differ significantly between the two groups. CONCLUSIONS We found no significant decrease in CV events or CV-associated deaths with intensive therapy, possibly because our between-group difference of LDL-C was lower than expected (27.7 mg/dL at 36 months of treatment). The potential benefit of achieving LDL-C <70 mg/dL in a treat-to-target strategy in high-risk patients deserves further investigation.

© 2018 The Authors. Background-—Mineralocorticoid receptor (MR) has pathological roles in various cell types, including renal tubule cells, myocytes, and smooth muscle cells; however, the role of MR in intestinal epithelial cells (IECs) has not been sufficiently evaluated. The intestine is the sensing organ of ingested sodium; accordingly, intestinal MR is expected to have essential roles in blood pressure (BP) regulation. Methods and Results-—We generated IEC-specific MR knockout (IEC-MR-KO) mice. With a standard diet, fecal sodium excretion was 1.5-fold higher in IEC-MR-KO mice, with markedly decreased colonic expression of b- and c-epithelial sodium channel, than in control mice. Urinary sodium excretion in IEC-MR-KO mice decreased by 30%, maintaining sodium balance; however, a low-salt diet caused significant reductions in body weight and BP in IEC-MR-KO mice, and plasma aldosterone exhibited a compensatory increase. With a high-salt diet, intestinal sodium absorption markedly increased to similar levels in both genotypes, without an elevation in BP. Deoxycorticosterone/salt treatment elevated BP and increased intestinal sodium absorption in both genotypes. Notably, the increase in BP was significantly smaller in IEC-MR-KO mice than in control mice. The addition of the MR antagonist spironolactone to deoxycorticosterone/salt treatment eliminated the differences in BP and intestinal sodium absorption between genotypes. Conclusions-—Intestinal MR regulates intestinal sodium absorption in the colon and contributes to BP regulation. These regulatory effects are associated with variation in epithelial sodium channel expression. These findings suggest that intestinal MR is a new target for studying the molecular mechanism of hypertension and cardiovascular diseases.

©The Japan Endocrine Society. We aimed to clarify the pathophysiological significance of total bilirubin (TB) in gestational diabetes mellitus (GDM). This was a cross-sectional study that included 616 pregnant Japanese women (368 normal glucose tolerance [NGT] and 248 GDM). Serum TB concentration, homeostasis model assessment of insulin resistance (HOMA-IR), and other clinical parameters were compared in NGT and GDM women. TB concentration was also compared according to the number of abnormal OGTT values. Logistic regression analysis was used to evaluate the association between TB and GDM prevalence. A multiple linear regression model was used to evaluate the association between TB and HOMA-IR. TB concentrations were significantly lower in GDM women than in NGT women. This result did not change after adjustments for TB sampling timing were made. Out of 248 GDM women, the prevalences of 1-and 2/3-abnormal OGTT values (1-and 2/3-AV) GDM were 72.2% (n = 179) and 27.8% (n = 69), respectively. In the multiple comparisons, TB concentrations were significantly lower in women with 2/3-AV GDM than in women with NGT and 1-AV GDM. Multiple logistic regression analysis showed that TB was a significantly associated factor for 2/3-AV, but not for total GDM. HOMA-IR was significantly higher in GDM women than in NGT women. The univariate, but not multivariate, analysis showed that TB was a significantly associated factor for HOMA-IR. Our findings suggest that hypobilirubinemia may be involved in the pathogenesis of GDM.

© 2017 Because the mucosa is the major entry route for most pathogens, the development of mucosal vaccines is a rational approach for protecting against these undesired agents. Mucosal administration of vaccine antigen is useful for non-infectious chronic diseases as well, because of its advantages over injection routes, including comparable efficacy in the induction of systemic immune responses, less pain, and no risk of adverse events at the injection site. However, because it is difficult to effectively induce and regulate antigen-specific mucosal and systemic immune responses when antigen alone is mucosally administered, an appropriate form of mucosal delivery vehicle must be used. Antigen delivery systems involving nanogels, which act as artificial chaperones and mucosal adhesives, are a promising approach to overcoming this problem. Here, we introduce current perspectives regarding the development of nanogel-based nasal vaccines for both infectious and lifestyle-related diseases.

© 2018 The Author(s). Nicotinamide N-methyltransferase (NNMT) catalyses the reaction between nicotinamide (NAM) and S-adenosylmethionine to produce 1-methylnicotinamide and S-adenosylhomocysteine. Recently, this enzyme has also been reported to modulate hepatic nutrient metabolism, but its role in the liver has not been fully elucidated. We developed transgenic mice overexpressing NNMT to elucidate its role in hepatic nutrient metabolism. When fed a high fat diet containing NAM, a precursor for nicotinamide adenine dinucleotide (NAD)+, these NNMT-overexpressing mice exhibit fatty liver deterioration following increased expression of the genes mediating fatty acid uptake and decreased very low-density lipoprotein secretion. NNMT overactivation decreased the NAD+ content in the liver and also decreased gene activity related to fatty acid oxidation by inhibiting NAD+-dependent deacetylase Sirt3 function. Moreover, the transgenic mice showed liver fibrosis, with the induction of inflammatory and fibrosis genes. Induced NNMT expression decreased the tissue methylation capacity, thereby reducing methylation of the connective tissue growth factor (CTGF) gene promoter, resulting in increased CTGF expression. These data indicate that NNMT links the NAD+ and methionine metabolic pathways and promotes liver steatosis and fibrosis. Therefore, targeting NNMT may serve as a therapeutic strategy for treating fatty liver and fibrosis.

© 2018 International Society for Peritoneal Dialysis. Most infections related to peritoneal dialysis (PD) are caused by common bacteria, and non-tuberculous mycobacteria are rare. The clinical characteristics and prognosis of PD patients with non-tuberculous mycobacterial infections were investigated at our hospital. Non-tuberculous mycobacteria were detected in 11 patients (exit-site infection, tunnel infection, and peritonitis in 3, 5, and 3 patients, respectively). Mycobacterium fortuitum, Mycobacterium chelonae, and Mycobacterium abscessus were identified in 4, 2, and 2 patients, respectively. Most patients with peritonitis or tunnel infection required catheter removal. During the study period (2007 – 2017), peritonitis occurred in 44 patients, including 3 patients (6.8%) with non-tuberculous mycobacterial peritonitis. When non-tuberculous mycobacterial infection occurs, multi-agent antibiotic therapy, unroofing surgery, and/or catheter replacement should be performed to prevent peritonitis.

© 2018, The Author(s). Background: Oral charcoal adsorbent AST-120 (AST) is reported to ameliorate renal dysfunction by the absorption of toxic substance in the gut. Recent study revealed that, in CKD, gut environment is disturbed including the decrease in tight junctions and Lactobacillus (Lact). In this study, we examined whether AST improves the renal dysfunction through gut environment. Method: Six-week-old spontaneously hypertensive rats (SHR) were rendered CKD by 5/6th nephrectomy (Nx). SHRs were divided into SHR (Sham), SHR with Nx (Nx), and Nx given AST (Nx + AST) (n = 10, each). After 12 weeks, rats were killed and biochemical parameters were explored. The gut flora was analyzed. Furthermore, gut molecular changes in tight junctions and toll-like receptors were examined. We also investigated the effects of the combination therapy with AST and Lact. Results: The increase in serum urea nitrogen and urinary protein excretion in Nx was restored in Nx + AST. The increased renal glomerulosclerosis in Nx was ameliorated in Nx + AST. Increases in serum uremic toxins and IL-6 in Nx were ameliorated in Nx + AST. The gut flora analysis revealed that the decrease in Lact in Nx was restored in Nx + AST. The downregulation in the tight junction and TLR2 in Nx was mitigated by AST. However, combination therapy failed to exhibit additional effects. Conclusion: AST ameliorated renal function with the restoration of Lact and tight junction through TLR pathway, which would mitigate systemic inflammation and contributed to their renoprotective effects. Our study provides a novel mechanism of the renoprotective effects by AST.

© 2018, The Japanese Society of Hypertension. In recent years, several post-interventional analyses of large-scale randomized controlled clinical trials have given us a new concept regarding the risk management of hypertension and cardiovascular diseases. The beneficial effects of intensive treatments were extended even after the interventions ended. This phenomenon is known as “metabolic memory” or “legacy effect”, and we recognized its clinical significance. A certain level of evidence in human and animal studies employing organ transplantation techniques has indicated that this type of “memory” resides in each organ and could be transferrable, erasable, and rewritable, which is similar to neuronal and immune “memory”. In this review, we define this memory as “organ memory” and summarize the current picture and future direction of this concept. “Organ memory” can be observed in many clinical settings, including in the control of hypertension, diabetes mellitus, and dyslipidemia. Several intensive treatments were demonstrated to have the potential to rewrite “organ memory”, leading to the curability of targeted diseases. “Organ memory” is the engraved phenotype of altered organ responsiveness acquired by a time-dependent accumulation of organ stress responses. Not only is the epigenetic change of key genes involved in the formation of “organ memory” but the alteration of multiple factors, including low molecular weight energy metabolites, immune mediators, and tissue structures, is involved as well. These factors intercommunicate during every stress response and carry out incessant remodeling in a certain direction in a spiral fashion through positive feedback mechanisms. Future studies should be directed toward the identification of the core unit of “organ memory” and its manipulation.

Calciphylaxis presents with painful purpura and intractable skin ulcers on the trunk and particularly the distal extremities, and it mainly occurs in patients on chronic dialysis. A 66-year-old man with renal failure due to diabetic nephropathy was on peritoneal dialysis alone for 1 year, followed by peritoneal dialysis combined with hemodialysis for 3 years. He developed calciphylaxis of the penis, which was diagnosed from the skin biopsy findings and clinical observation. To treat this condition, PD was stopped and HD was performed three times a week. In addition, warfarin therapy was discontinued and infusion of sodium thiosulfate was performed. The penile ulcers decreased in size and pain was markedly improved, so the patient was discharged from hospital. Following discharge, PD was resumed after changing the peritoneal dialysis fluid to bicarbonate-buffered dialysate. The penile ulcers eventually resolved completely. There have been very few reports about calciphylaxis in patients on combined dialysis modalities. In our patient, penile calciphylaxis progressed when lactate-buffered peritoneal dialysis fluid was used and resolved after switching to bicarbonate-buffered fluid together with cessation of warfarin therapy and infusion of sodium thiosulfate.

© 2018, The Japanese Society of Hypertension. Pre-emptive medicine is a novel medical concept proposed in Japan that aims to precisely predict the onset and progression of diseases and to provide therapeutic interventions during early stages, before symptoms appear. The concept of pre-emptive medicine considers the time-course of a disease in each individual and seeks medical interventions to prevent disease progression. Suitable and promising targets for pre-emptive medicine are non-communicable diseases, including hypertension. Recent advances in genomic analysis, information technology, and artificial intelligence should make this medical concept feasible in the near future. In this review, we focused on pre-emptive medicine for hypertension, referring to concrete plans for the future direction of this research. The ultimate goal of pre-emptive medicine is to completely prevent the onset and progression of hypertension by precisely predicting the elevation of blood pressure and performing interventions to avoid it. The diagnostic processes of hypertension, from the standpoint of pre-emptive medicine, should include the detection of abnormal blood pressure regulation as the earliest manifestation of the disease, the depiction of the present status of hypertension in an individual (“nowcasting”), and a prediction of the future trajectory of the disease (“forecasting”). Novel therapeutic strategies for hypertension, from the standpoint of pre-emptive medicine, should aim for the regression of hypertension through early treatments and the remission of hypertension through intermittent intensive therapies. An efficient modification of lifestyle and therapies, according to the progression of hypertension, should be required. If pre-emptive medicine for hypertension becomes established, it would greatly contribute to the extension of a healthy lifespan, which cannot yet be satisfactorily achieved.

© 2018 American Heart Association, Inc. There have been several clinical studies examining the factors associated with cardiovascular disease (CVD) in patients with primary aldosteronism (PA); however, their results have left it unclear whether CVD is affected by the plasma aldosterone concentration or hypokalemia. We assessed the PA database established by the multicenter JPAS (Japan Primary Aldosteronism Study) and compared the prevalence of CVD among patients with PA with that among age-, sex-, and blood pressure-matched essential hypertension patients and participants with hypertension in a general population cohort. We also performed binary logistic regression analysis to determine which parameters significantly increased the odds ratio for CVD. Of the 2582 patients with PA studied, the prevalence of CVD, including stroke (cerebral infarction, cerebral hemorrhage, or subarachnoid hemorrhage), ischemic heart disease (myocardial infarction or angina pectoris), and heart failure, was 9.4% (stroke, 7.4%; ischemic heart disease, 2.1%; and heart failure, 0.6%). The prevalence of CVD, especially stroke, was higher among the patients with PA than those with essential hypertension/ hypertension. Hypokalemia (K+ ≤3.5 mEq/L) and the unilateral subtype significantly increased adjusted odds ratios for CVD. Although aldosterone levels were not linearly related to the adjusted odds ratio for CVD, patients with plasma aldosterone concentrations ≥125 pg/mL had significantly higher adjusted odds ratios for CVD than those with plasma aldosterone concentrations <125 pg/mL. Thus, patients with PA seem to be at a higher risk of developing CVD than patients with essential hypertension. Moreover, patients with PA presenting with hypokalemia, the unilateral subtype, or plasma aldosterone concentration ≥125 pg/mL are at a greater risk of CVD and have a greater need for PA-specific treatments than others.

© 2018 The Author(s). Background: Pulmonary nocardiosis frequently develops as an opportunistic infection in cell-mediated immunosuppressive patients, and sometimes requires differentiation from pulmonary malignancy. Ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) is a neoplastic disorder which leads to impaired cell-mediated immunity, and is commonly associated with small cell lung cancer (SCLC). Because pulmonary infection and causative malignancy can appear as pulmonary lesions with EAS, differentiation of these diseases remains a critical issue for physicians. Case presentation: A 52-year-old woman with progressive lower limb paralysis and general fatigue was referred to us. She had been diagnosed with olfactory neuroblastoma (ONB) and treated with surgery and radiation therapy 10 years before the referral and had required stereotactic radiosurgery and chemotherapy 4 years later for a relapse of the ONB. On referral, she presented with Cushing's syndrome with elevated cortisol and ACTH levels. Potassium supplement improved her symptoms; however, a month later, she was urgently hospitalized due to acute pleuritic chest pain on inspiration. Chest computed tomography revealed left lower lobular consolidations and a contralateral nodule in the right middle lobe. The clinical history and laboratory work-up suggested that her Cushing's syndrome had most likely arisen from EAS. Additionally, the lungs were suspected as the ACTH source due to high levels of progastrin-releasing peptide and progressive pulmonary consolidation with a contralateral nodule, suggesting SCLC. However, histological examination from bronchoscopy revealed no evidence of malignancy, and Nocardia cyriacigeorgica was isolated from bronchoalveolar lavage fluid. Sulfamethoxazole/trimethoprim improved her pulmonary lesions. Somatostatin receptor scintigraphy revealed strong tracer uptake in the ONB lesions, indicating that the origin of the EAS was the olfactory tumor. However, histological examination of ONB specimens resected 10 years earlier showed no intracytoplasmic immunopositivity for ACTH. Conclusions: We highlight a rare case of pulmonary nocardiosis, which was associated with EAS mimicking SCLC, and was related to ONB transformation. Nocardiosis has to be considered even though anamnestic, clinical, and radiological aspects suggest the presence of metastasis. Additionally, physicians should carefully monitor patients with ONB for the development of Cushing's symptoms because the tumor can transform into an ACTH-producing form, even after long-term follow-up.

© 2019 The Author(s) Nicotinamide adenine dinucleotide (NAD + ) metabolism plays a critical role in kidneys. We previously reported that decreased secretion of a NAD + precursor, nicotinamide mononucleotide (NMN), from proximal tubules (PTs) can trigger diabetic albuminuria. In the present study, we investigated the role of NMN-producing enzyme nicotinamide phosphoribosyltransferase (Nampt) in diabetic nephropathy. The expression of Nampt in PTs was downregulated in streptozotocin (STZ)-treated diabetic mice when they exhibited albuminuria. This albuminuria was ameliorated in PT-specific Nampt-overexpressing transgenic (TG) mice. PT-specific Nampt-conditional knockout (Nampt CKO) mice exhibited TBM thickening and collagen deposition, which were associated with the upregulation of the profibrogenic gene TIMP-1. Nampt CKO mice also exhibited the downregulation of sirtuins, particularly in Sirt6. PT-specific Sirt6-knockout mice exhibited enhanced fibrotic phenotype resembling that of Nampt CKO mice with increased Timp1 expression. In conclusion, the Nampt-Sirt6 axis in PTs serves as a key player in fibrogenic extracellular matrix remodeling in diabetic nephropathy. Muraoka et al. reveal that the Nampt-Sirt6 axis in proximal tubules serves as a key player in fibrogenic extracellular matrix remodeling in diabetic nephropathy.

© 2019 Japan Diabetes Society. All rights reserved. Although the current guidelines recommend the use of "individualized" HbA1c goals for patient-centered diabetes care, information regarding the satisfaction of patients with their glycemic control is insufficient. In this study, we aimed to clarify the satisfaction of patients with their glycemic control and to determine the related factors. Outpatients with diabetes were asked to answer questionnaires that included a question about their satisfaction with their glycemic control, and responses were obtained from 254 patients with type 2 diabetes and 22 patients with type 1 diabetes. Twenty-eight percent of the patients answered "satisfied", while 18 % answered "not satisfied". The satisfaction with glycemic control was significantly correlated with HbA1c, adherence to dietary therapy, satisfaction with doctor and clinic, satisfaction with medical cost, intention to drop out and satisfaction with diabetes treatment. Thus, patient satisfaction with glycemic control should be recognized as an important patient-reported outcome, and may be affected by the self-efficacy of dietary therapy and the patient's relationship with medical staff.

© 2017, The Japan Diabetes Society. Aims: The aim of this study was to investigate the association between serum total bilirubin concentration and complicated macrovascular diseases, such as cerebrovascular disease (CBVD), cardiovascular disease (CAD), and peripheral arterial disease (PAD), in patients with type 2 diabetes. Methods: We performed a retrospective cross-sectional study in 674 patients with type 2 diabetes. Serum total bilirubin concentration was compared between patients with and without CBVD, CAD, and PAD. Logistic regression analyses were performed to identify risk factors for CBVD, CAD, and PAD. Associations between total bilirubin concentration and the number of complicated macrovascular diseases were analyzed. Results: Patients with CBVD and PAD showed significantly lower serum total bilirubin concentrations than did those patients without those diseases. However, the bilirubin concentration did not differ between patients with and without CAD. Total bilirubin concentration was an independent predictor of CBVD, but not of CAD or PAD. There was a statistically significant trend for a decrease in bilirubin concentration in the presence of an increasing number of macrovascular diseases. Conclusion: The presence of more than one macrovascular disease, called polyvascular disease, carries a high risk for cardiovascular mortality. Serum total bilirubin concentration may be useful as a clinical biomarker of polyvascular disease.