Screening Cutoff Values for the Detection of Aldosterone-Producing Adenoma by LC-MS/MS and a Novel Noncompetitive CLEIA.

Context: Detecting patients with surgically curable aldosterone-producing adenoma (APA) among hypertensive individuals is clinically pivotal. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is the ideal method of measuring plasma aldosterone concentration (PAC) because of the inaccuracy of conventional chemiluminescent enzyme immunoassay (CLEIA). However, LC-MS/MS is expensive and requires expertise. We have developed a novel noncompetitive CLEIA (NC-CLEIA) for measuring PAC in 30 minutes. Objective: This work aimed to validate NC-CLEIA PAC measurements by comparing them with LC-MS/MS measurements and determining screening cutoffs for both measurements detecting APA. Methods: We retrospectively measured PAC using LC-MS/MS and NC-CLEIA in 133 patients with APA, 100 with bilateral hyperaldosteronism, and 111 with essential hypertension to explore the accuracy of NC-CLEIA PAC measurements by comparing with LC-MS/MS measurements and determined the cutoffs for detecting APA. Results: Passing-Bablok analysis revealed that the values by NC-CLEIA (the regression slope, intercept, and correlation coefficient were 0.962, -0.043, and 0.994, respectively) were significantly correlated and equivalent to those by LC-MS/MS. Bland-Altman plot analysis of NC-CLEIA and LC-MS/MS also demonstrated smaller systemic errors (a bias of -0.348 ng/dL with limits of agreement of -4.390 and 3.694 within a 95% CI) in NC-CLEIA than LC-MS/MS. The receiver operating characteristic analysis demonstrated that cutoff values for aldosterone/renin activity ratio obtained by LC-MS/MS and NC-CLEIA were 31.2 and 31.5 (ng/dL per ng/mL/hour), with a sensitivity of 91.0% and 90.2% and specificity of 75.4% and 76.8%, respectively, to differentiate APA from non-APA. Conclusion: This newly developed NC-CLEIA for measuring PAC could serve as a clinically reliable alternative to LC-MS/MS.

Factors Associated with the Antihypertensive Effect of Esaxerenone and Serum Potassium Elevation: A Pooled Analysis of Seven Phase III Studies.

INTRODUCTION: This study investigated factors associated with the antihypertensive effects of esaxerenone and the incidence of serum potassium elevation in patients with hypertension. METHODS: Using pooled data from seven phase III studies, the study analyzed factors associated with changes in office systolic (SBP) and diastolic (DBP) blood pressure from baseline to 12 weeks, and factors associated with incidence of serum potassium levels ≥ 5.5 mEq/L in esaxerenone-treated patients. RESULTS: Overall, 1466 and 1472 patients were included in the full analysis and safety analysis sets, respectively. Male sex (4.02/2.40 mmHg), weight ≥ 78.4 kg (4.62/2.09 mmHg), hypertension duration ≥ 10 years (2.66/1.71 mmHg), prior antihypertensive treatment (2.38/1.40 mmHg), plasma aldosterone concentration ≥ 120 pg/mL (1.66/1.17 mmHg), urinary albumin-to-creatinine ratio (UACR) ≥ 300 mg/gCr (8.94/4.85 mmHg) or 30-299 mg/gCr (5.17/4.15 mmHg), and smoking (2.62/1.27 mmHg) were associated with mean changes in SBP and DBP. Fasting blood glucose ≥ 126 mg/dL (- 2.73 mmHg) was associated with the mean change in SBP only, and older age (65-74 years, - 2.12 mmHg; and ≥ 75 years, - 3.06 mmHg) with mean change in DBP only. Factors significantly associated with incidence of serum potassium levels ≥ 5.5 mEq/L were higher baseline serum potassium (≥ 4.5 mEq/L, odds ratio [OR] 6.702); lower estimated glomerular filtration rate (≥ 90 mL/min/1.73 m2, OR 0.148; 60-89 mL/min/1.73 m2, OR 0.331 vs 30-59 mL/min/1.73 m2, respectively); higher UACR (30-299 mg/gCr, OR 7.317); higher DBP (≥ 100 mmHg, OR 3.248); and grade I hypertension (OR 2.168). CONCLUSION: Esaxerenone is effective in patients with a broad range of backgrounds, though some factors may predict increased benefit. Regarding elevated serum potassium, careful therapeutic management is recommended for patients with higher baseline serum potassium and reduced renal function. CLINICAL TRIAL REGISTRATION: UMIN000047026.

The renoprotective effect of esaxerenone independent of blood pressure lowering: a post hoc mediation analysis of the ESAX-DN trial.

Angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) are recommended as first-line drugs for hypertension with diabetic nephropathy owing to their renoprotective effect; however, their effect beyond lowering blood pressure (BP) has not been confirmed. Recent studies have shown that aldosterone plays a key role in causing renal injury; therefore, it is likely that mineralocorticoid receptor (MR) blockers inhibit aldosterone-induced renal damage in different ways from ACE inhibitors and ARBs. Therefore, we investigated the mechanism of the effect of an MR blocker on reducing the urinary albumin-to-creatinine ratio (UACR) using data from a randomized, double-blind, placebo-controlled phase 3 study (ESAX-DN) of a new nonsteroidal MR blocker, esaxerenone. This post hoc analysis used a novel statistical method to quantitatively estimate the effect of esaxerenone on UACR reduction mediated, or not mediated, by changes in systolic BP (SBP) and/or estimated glomerular filtration rate (eGFR). The proportion of the mediated effect by SBP changes to the total effect on UACR reduction was 9.8-10.7%; the UACR was reduced to 0.903-0.911 times the baseline at the end of treatment through the SBP-related pathway and to 0.422-0.426 times the baseline through the non-SBP-related pathway. Even considering both SBP and eGFR simultaneously, the proportion of the mediated effect was 21.9-28.1%. These results confirm that esaxerenone has a direct UACR-lowering effect independent of BP lowering and that its magnitude is much larger than that of the BP-dependent effect. Thus, esaxerenone could be a UACR-reducing treatment option for patients with diabetic nephropathy.

Marked reduction of proteinuria after removal of a growth hormone-producing pituitary adenoma in a patient with focal segmental glomerulosclerosis: a case report and literature review.

Focal segmental glomerulosclerosis is a rare complication of acromegaly. A 74-year-old man was found to have acromegaly features such as enlargement of the forehead, nose, and hands. Laboratory tests showed a urine protein/creatinine ratio of 3.16 g/gCr and serum creatinine of 1.34 mg/dL. The levels of growth hormone and insulin-like growth factor I were markedly elevated, and the growth hormone level was not suppressed after 75 g oral glucose loading. Magnetic resonance imaging revealed a pituitary tumor with a diameter of 1.2 cm. Renal biopsy confirmed the diagnosis of focal segmental glomerulosclerosis. Transsphenoidal resection of the pituitary tumor led to remission of acromegaly and reduction in proteinuria highlighting the causal link between growth hormone overproduction and proteinuria. Treatment of acromegaly may be effective for acromegaly-associated focal segmental glomerulosclerosis.

Safety and feasibility of radiofrequency ablation using bipolar electrodes for aldosterone-producing adenoma: a multicentric prospective clinical study.

Evaluation of feasibility and safety of percutaneous radiofrequency ablation using bipolar radiofrequency devices in a prospective multicenter cohort of patients with benign aldosterone-producing adenoma. A total of five institutions participated. CT-guided percutaneous RFA was performed for patients diagnosed as APA. The safety of the procedure was evaluated using the Common Terminology Criteria for Adverse Events. During the 84-day follow-up period, serial changes in plasma aldosterone concentration and plasma renin activity were measured. The percentage of patients with normalized hormonal activity after the procedure, was calculated with 95% confidence intervals. Forty patients were enrolled, and two patients were excluded for cerebral hemorrhage and no safe puncture root. In another patients, RFA was tried, but an intraprocedural intercostal arterial injury occurred. Consequently, RFA was completed in thirty-seven patients (20 men, 17 women; mean age, 50.4 ± 10.0 year). The tumor size was 14.8 ± 3.8 mm. The treatment success rate of the ablation was 94.6% (35/37), and a 2nd session was performed in 2.7% (1/37) patients. Grade 4 adverse events were observed in 4 out of 38 sessions (10.5%). The normalization of plasma aldosterone concentration or aldosterone-renin ratio was 86.5% (72.0-94.1: 95% confidence interval) on day 84. Percutaneous CT-guided RFA for APA using a bipolar radiofrequency system was safe and feasible with clinical success rate of 86.5% on day 84.

The Time to Reconsider Mineralocorticoid Receptor Blocking Strategy: Arrival of Nonsteroidal Mineralocorticoid Receptor Blockers.

PURPOSE OF REVIEW: The study aims to verify the advantages of nonsteroidal mineralocorticoid receptor blockers (MRBs) in the management of hypertension and cardiovascular and renal diseases, comparing with conventional MRBs. RECENT FINDINGS: Based on the unique structures, the nonsteroidal MRBs have higher selectivity for mineralocorticoid receptors (MRs) and show no agonist activity for major steroid hormone receptors in contrast to steroidal MRBs. Today, there are two nonsteroidal MRBs, esaxerenone and finerenone, which completed phase 3 clinical trials. Series of clinical trials have shown that both agents achieve similar MR blockade with smaller doses as compared with steroidal MRBs, but have no off-target side effect such as gynecomastia. Esaxerenone has persistent blood pressure-lowering effects in various hypertensive populations, including essential hypertension and those with diabetes and/or chronic kidney disease, while finerenone has demonstrated reduction of the cardiovascular risk rather than blood pressure in patients with diabetes and chronic kidney disease. Nonsteroidal MRBs are a more refined agent which contributes to appropriate MR blocking with minimized unpleasant adverse effects.

Reduction in the magnitude of serum potassium elevation in combination therapy with esaxerenone (CS-3150) and sodium-glucose cotransporter 2 inhibitor in patients with diabetic kidney disease: Subanalysis of two phase III studies.

AIMS/INTRODUCTION: We evaluated the effect of co-administration of esaxerenone and a sodium-glucose cotransporter 2 (SGLT2) inhibitor on the magnitude of serum potassium elevation in Japanese patients with diabetic kidney disease. MATERIALS AND METHODS: We carried out a prespecified subanalysis of data from two phase III studies: a multicenter, randomized, double-blind, placebo-controlled trial in patients with type 2 diabetes and microalbuminuria (J308); and a multicenter, single-arm, open-label trial in patients with type 2 diabetes and macroalbuminuria (J309). Changes in serum potassium levels during the studies and other measures were evaluated according to SGLT2 inhibitor use. RESULTS: In both studies, time-course changes in serum potassium levels, and incidence rates of serum potassium elevation were lower in patients with co-administration of SGLT2 inhibitor in both the placebo and esaxerenone groups than those without the inhibitor. In contrast, time-course changes and mean percentage changes from baseline in urinary albumin-to-creatinine ratio, the proportion of patients with albuminuria remission and time-course changes in blood pressure did not change with or without SGLT2 inhibitor, whereas the albumin-to-creatinine ratio and blood pressure were reduced with esaxerenone. The blood glucose-lowering effect of SGLT2 inhibitor was not affected by esaxerenone. CONCLUSIONS: In Japanese patients with type 2 diabetes and albuminuria treated with esaxerenone, concomitant use of SGLT2 inhibitor reduced the magnitude of serum potassium elevation without any change of its antihypertensive and albuminuria-suppressing effects. Co-administration of esaxerenone and SGLT2 inhibitor might be a beneficial treatment option for patients with diabetic kidney disease.

Electrolyzed hydrogen-rich water for oxidative stress suppression and improvement of insulin resistance: a multicenter prospective double-blind randomized control trial.

INTRODUCTION: Electrolyzed hydrogen-rich water (EHW) is known to have suppressive effects on oxidative stress (OS). However, its benefit in type 2 diabetes mellitus (T2DM) remains unclear. This study aimed to investigate the effect of EHW on T2DM. METHODS: This was a multicenter, prospective, double-blind, randomized controlled trial of 50 patients with T2DM who were assigned to the EHW or filtered water (FW) groups. The primary endpoint was changes in insulin resistance (IR) evaluated using the homeostasis model assessment of insulin resistance (HOMA-IR). OS markers such as urinary 8-hydroxy-2'-deoxyguanosine excretion (8-OHdG), plasma diacron-reactive oxygen metabolites (d-ROM), and plasma biological antioxidant potential (BAP) and other clinical data, including serum lactate concentration (lactate), were evaluated. RESULTS: There were no significant differences in the changes in HOMA-IR between the EHW and FW groups. However, lactate levels decreased significantly in the EHW group, and this decrease was significantly correlated with a reduction in HOMA-IR, fasting plasma glucose, and fasting plasma insulin level. Serum lactate level also significantly correlated to decreased insulin bolus secretion after 90 min with glucose loading in the EHW subjects with HOMA-IR > 1.73. No EHW treatment-related adverse effects were observed. CONCLUSION: There were no significant effect of EHW in the change in HOMA-IR in this study; larger-scale and longer-term study are needed to verify the effects of EHW in T2DM patients. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13340-021-00524-3.

Direct comparison of the reproducibility of in-office and self-measured home blood pressures.

OBJECTIVE: The aim was to compare short-term and long-term reproducibilities of in-office unattended blood pressure (BP), namely automated office blood pressure (AOBP), conventionally measured attended office BP, and self-measured home BP. METHODS: A multicentre, clinical study was conducted in Japan, and 287 Japanese outpatients on antihypertensive drug medication were followed-up for 1 year. RESULTS: The intensity of drug treatment was sustained consistently throughout the study period (defined daily doses, 1.62-1.68; P = 0.12). The mean SBP differences between baseline and 1 month later, as well as baseline and 1 year later, were less than 1.5 mmHg, whereas the standard deviations of the differences for home, AOBP, and attended office measurements for the 1-year interval were 7.7, 14.5, and 15.3 mmHg, respectively. The coefficients of variation were significantly smaller for home BP than for AOBP among all patients at both 1-month and 1-year intervals (P < 0.0001). In the 1-month interval, partial correlation coefficients of home BP (r, 0.73/0.88 for systolic/diastolic measures) were significantly higher than of conventional BP (r, 0.47/0.69). However, the correlations converged to the modest level regardless of BP information (r, 0.49-0.54/0.63-0.73) when the 1-year interval was assessed. Results were confirmatory when patients on the same drug regimen (n = 167) were analysed. CONCLUSION: A higher reproducibility of home BP was demonstrated compared with in-office BP, including AOBP. However, the modest correlations for the 1-year interval support the importance of regular assessment of BP, regardless of in-office or home measurements for treatment of hypertension.

Central-to-peripheral stiffness gradients determine diastolic pressure and flow fluctuation waveforms: time domain analysis of femoral artery pulse.

OBJECTIVE: Blood pressure fluctuates during diastole to create a dicrotic wave but the mechanistic origin remains poorly understood. We sought to investigate the characteristics and determinants of diastolic pressure and flow fluctuations with a focus on stiffness gradients between the central aorta and peripheral arteries. METHODS: Using applanation tonometry and duplex ultrasound, pulse waveforms were recorded on the femoral artery in 592 patients (age: 55 ±â€Š14 years) to estimate the diastolic pressure fluctuation as a residual wave against the mono-exponential decay and the diastolic flow fluctuation as a bidirectional (forward and reverse) velocity wave. The radial, carotid, and dorsalis pedis pressures were also recorded to measure the peripheral/aortic pulse pressure (PP) and pulse wave velocity (PWV) ratios. RESULTS: There were close resemblances between the femoral pressure and flow fluctuation waveforms. The pressure and flow fluctuations were mutually correlated in relative amplitude as indexed to the total pulse height (r = 0.63), and the former temporally followed the latter. In multivariate-adjusted models, higher peripheral/aortic PP and PWV ratios were independently associated with greater pressure and flow fluctuation indices (P < 0.001). Mediation analysis revealed that the associations of PP and PWV ratios with the pressure fluctuation index were largely mediated by the flow fluctuation index [indirect/total effect ratio: 57 (95% CI 42-80)% and 54 (30-100)%, respectively]. CONCLUSION: These results suggest that central-to-peripheral pulse amplification and stiffness gradients contribute to triphasic flow fluctuations and dicrotic pressure waves. Diminished or inverted stiffness gradients caused by aortic stiffening may thus reduce diastolic runoff leading to ischemic organ damage.

Effect of esaxerenone on nocturnal blood pressure and natriuretic peptide in different dipping phenotypes.

There are limited data on the nighttime blood pressure (BP)-lowering effect of esaxerenone and its effect on N-terminal pro b-type natriuretic peptide (NT-proBNP), a predictor of cardiovascular risk, according to different dipping patterns of nocturnal BP. This was a post hoc analysis of a multicenter, open-label, long-term phase 3 study of esaxerenone, a new highly selective mineralocorticoid receptor blocker, in patients with essential hypertension. Patients were classified by dipping pattern (extreme dippers, dippers, non-dippers, risers). Mean changes in BP, changes in dipping pattern, mean NT-proBNP levels, and percentage of patients with normal NT-proBNP levels (<55 pg/mL) at baseline and Weeks 12 and 28 were evaluated. Nighttime systolic BP decreased in all dipping pattern groups at Week 28, with the riser group showing the greatest change (-25.5 mmHg). A significant shift in dipping pattern and riser/non-dipper pattern changes to dipper/extreme dipper pattern were found from baseline to Week 28 (p < 0.0001). The prevalence of the riser pattern decreased from 14.4% to 9.8%, and that of the non-dipper pattern from 44.7% to 39.2%. The decrease in NT-proBNP from baseline to Week 28 was statistically significant in risers, non-dippers, dippers, and extreme dippers (p < 0.001, respectively). At baseline, the proportion of patients with NT-proBNP <55 pg/mL was lowest in risers versus the other dipping pattern types, but after reductions in NT-proBNP in all groups to Week 28, these differences disappeared. Long-term administration of esaxerenone may be a useful treatment option for nocturnal hypertension, especially in patients with a riser pattern.

Risk Classification for Metabolic Syndrome and the Incidence of Cardiovascular Disease in Japan With Low Prevalence of Obesity: A Pooled Analysis of 10 Prospective Cohort Studies.

Background It is uncertain whether risk classification under the nationwide program on screening and lifestyle modification for metabolic syndrome captures well high-risk individuals who could benefit from lifestyle interventions. We examined the validity of risk classification by linking the incidence of cardiovascular disease (CVD). Methods and Results Individual-level data of 29 288 Japanese individuals aged 40 to 74 years without a history of CVD from 10 prospective cohort studies were used. Metabolic syndrome was defined as the presence of high abdominal obesity and/or overweight plus risk factors such as high blood pressure, high triglyceride or low high-density lipoprotein cholesterol levels, and high blood glucose levels. The risk categories for lifestyle intervention were information supply only, motivation-support intervention, and intensive support intervention. Sex- and age-specific hazard ratios and population attributable fractions of CVD, which were also further adjusted to consider non-high density lipoprotein cholesterol levels, were estimated with reference to nonobese/overweight individuals, using Cox proportional hazard regression. Since the reference category included those with risk factors, we set a supernormal group (nonobese/overweight with no risk factor) as another reference. We documented 1023 incident CVD cases (565 men and 458 women). The adjusted CVD risk was 60% to 70% higher in men and women aged 40 to 64 years receiving an intensive support intervention, and 30% higher in women aged 65 to 74 years receiving a motivation-support intervention, compared with nonobese/overweight individuals. The population attributable fractions in men and women aged 40 to 64 years receiving an intensive support intervention were 17.7% and 6.6%, respectively, while that in women aged 65 to 74 years receiving a motivation-support intervention was 9.4%. Compared with the supernormal group, nonobese/overweight individuals with risk factors had similar hazard ratios and population attributable fractions as individuals with metabolic syndrome. Conclusions Similar CVD excess and attributable risks among individuals with metabolic syndrome components in the absence and presence of obesity/overweight imply the need for lifestyle modification in both high-risk groups.

Renal Injuries in Primary Aldosteronism: Quantitative Histopathological Analysis of 19 Patients With Primary Adosteronism.

[Figure: see text].

Myeloid cell-derived coagulation tissue factor is associated with renal tubular damage in mice fed an adenine diet.

Patients with chronic kidney disease (CKD) commonly exhibit hypercoagulability. Increased levels of uremic toxins cause thrombogenicity by increasing tissue factor (TF) expression and activating the extrinsic coagulation cascade. TF is induced in monocytes and macrophages under pathological conditions, such as inflammatory diseases. However, the role of monocyte myeloid cell TF in CKD progression remains unclear. We aimed to clarify this issue, and the present study found that patients with CKD had elevated levels of D-dimer, a marker of fibrin degradation, which was associated with decreased estimated glomerular filtration rate and increased serum levels of uremic toxins, such as indoxyl sulfate. In vitro studies showed that several uremic toxins increased cellular TF levels in monocytic THP-1 cells. Mice with TF specifically deleted in myeloid cells were fed an adenine diet to cause uremic kidney injury. Myeloid TF deletion reduced tubular injury and pro-inflammatory gene expression in the kidneys of adenine-induced CKD but did not improve renal function as measured by plasma creatinine or blood urea nitrogen. Collectively, our findings suggest a novel concept of pathogenesis of coagulation-mediated kidney injury, in which elevated TF levels in monocytes under uremic conditions is partly involved in the development of CKD.

Efficacy and safety of esaxerenone (CS-3150) in Japanese patients with type 2 diabetes and macroalbuminuria: a multicenter, single-arm, open-label phase III study.

BACKGROUND: Esaxerenone has potential renoprotective effects and reduces the urinary albumin-to-creatinine ratio (UACR) in patients with diabetic kidney disease and overt nephropathy. We investigated the efficacy and safety of esaxerenone in Japanese patients with type 2 diabetes (T2D) and macroalbuminuria (UACR ≥ 300 mg/g creatinine). METHODS: We conducted a multicenter, single-arm, open-label phase III study in 56 patients with T2D and UACR ≥ 300 mg/g creatinine with estimated glomerular filtration rate (eGFR) ≥ 30 mL/min/1.73 m2 and treated with a renin-angiotensin system inhibitor. Patients received esaxerenone for 28 weeks at 1.25 mg/day initially with titration to 2.5 mg/day based on serum potassium (K+) monitoring. Efficacy was evaluated as the change in UACR from baseline to week 28. Safety endpoints included adverse events (AEs), incidence of serum K+ increase, and change in eGFR from baseline. RESULTS: UACR decreased by 54.6% (95% CI 46.9%, 61.3%) on average from baseline (544.1 mg/g creatinine) to the end of treatment (246.8 mg/g creatinine); 51.8% of patients showed improvement to early nephropathy. AE incidence was 69.6%. Three patients (5.4%) had serum K+ levels ≥ 6.0 mEq/L or ≥ 5.5 mEq/L on two consecutive occasions. Hyperkalemia in two patients was transient and resolved during the treatment period. One patient discontinued following two consecutive serum K+ values ≥ 5.5 mEq/L. The maximum change from baseline in eGFR was - 8.3 mL/min/1.73 m2 at week 24. CONCLUSIONS: Esaxerenone reduced UACR in Japanese patients with T2D and UACR ≥ 300 mg/g creatinine; more than half experienced a transition from UACR ≥ 300 mg/g creatinine to UACR < 300 mg/g creatinine. CLINICAL TRIAL REGISTRATION: JapicCTI-173696.

Different clinical impact of hyperuricemia according to etiologies of chronic kidney disease: Gonryo Study.

BACKGROUND: Hyperuricemia is highly prevalent in chronic kidney disease (CKD) patients, but the evidence for a relationship between uric acid (UA) and clinical outcomes in CKD patients is limited and inconsistent. We hypothesized that UA has a different impact on clinical outcomes according to the underlying disease causing CKD. METHODS: This study prospectively investigated the associations between UA and renal and non-renal outcomes according to the underlying disease causing CKD in 2,797 Japanese patients under the care of nephrologists. The patients were categorized into four groups: primary renal disease (n = 1306), hypertensive nephropathy (n = 467), diabetic nephropathy (n = 275), and other nephropathy (n = 749). The renal outcome was defined as end-stage renal disease (ESRD), and the non-renal outcome was defined as a composite endpoint of cardiovascular events (CVEs) and all-cause mortality. RESULTS: During a median 4.8-year follow-up, 359 (12.8%) patients reached the renal outcome, and 260 (9.3%) reached the non-renal outcome. In the all-patient analysis, hyperuricemia was not associated with the risks for renal and non-renal outcomes, but in primary renal disease (PRD) and hypertensive renal disease (HTN) patients, hyperuricemia was significantly associated with non-renal outcomes. Per 1 mg/dl higher UA level, multivariable adjusted hazard ratio was 1.248 (95% CI: 1.003 to 1.553) for PRD, and 1.250 (1.035 to 1.510) for HTN. Allopurinol did not reduce the risks for renal and non-renal outcomes, both in all patients and in the subgroup analysis. CONCLUSIONS: The effect of hyperuricemia on clinical outcomes in CKD patients varies according to the underlying disease causing CKD. Hyperuricemia is an independent risk factor for non-renal outcomes in primary renal disease and hypertensive renal disease patients. Allopurinol did not decrease the risks for renal and non-renal outcomes.

Renal interstitial fibroblasts coproduce erythropoietin and renin under anaemic conditions.

BACKGROUND: Erythrocyte mass contributes to maintaining systemic oxygen delivery and blood viscosity, with the latter being one of the determinants of blood pressure. However, the physiological response to blood pressure changes under anaemic conditions remain unknown. METHODS AND FINDINGS: We show that anaemia decreases blood pressure in human patients and mouse models. Analyses of pathways related to blood pressure regulation demonstrate that anaemia enhances the expression of the gene encoding the vasopressor substance renin in kidneys. Although kidney juxtaglomerular cells are known to continuously produce renin, renal interstitial fibroblasts are identified in the present study as a novel site of renin induction under anaemic hypotensive conditions in mice and rats. Notably, some renal interstitial fibroblasts are found to simultaneously express renin and the erythroid growth factor erythropoietin in the anaemic mouse kidney. Antihypertensive agents but not hypoxic stimuli induced interstitial renin expression, suggesting that blood pressure reduction triggers interstitial renin induction in anaemic mice. The interstitial renin expression was also detected in injured fibrotic kidneys of the mouse and human, and the renin-expressing interstitial cells in murine fibrotic kidneys were identified as myofibroblasts originating from renal interstitial fibroblasts. Since the elevated expression levels of renin in fibrotic kidneys along with progression of renal fibrosis were well correlated to the systemic blood pressure increase, the renal interstitial renin production seemed to affect systemic blood pressure. INTERPRETATION: Renal interstitial fibroblasts function as central controllers of systemic oxygen delivery by producing both renin and erythropoietin. FUNDING: Grants-in-Aid from Japan Society for the Promotion of Science (JSPS) KAKENHI (17K19680, 15H04691, and 26111002) and the Takeda Science Foundation.

Nicotinamide Attenuates the Progression of Renal Failure in a Mouse Model of Adenine-Induced Chronic Kidney Disease.

Nicotinamide adenine dinucleotide (NAD+) supplies energy for deoxidation and anti-inflammatory reactions fostering the production of adenosine triphosphate (ATP). The kidney is an essential regulator of body fluids through the excretion of numerous metabolites. Chronic kidney disease (CKD) leads to the accumulation of uremic toxins, which induces chronic inflammation. In this study, the role of NAD+ in kidney disease was investigated through the supplementation of nicotinamide (Nam), a precursor of NAD+, to an adenine-induced CKD mouse model. Nam supplementation reduced kidney inflammation and fibrosis and, therefore, prevented the progression of kidney disease. Notably, Nam supplementation also attenuated the accumulation of glycolysis and Krebs cycle metabolites that occurs in renal failure. These effects were due to increased NAD+ supply, which accelerated NAD+-consuming metabolic pathways. Our study suggests that Nam administration may be a novel therapeutic approach for CKD prevention.