Characterization of muscarinic and P2X receptors in the urothelium and detrusor muscle of the rat bladder

AbstractMuscarinic and purinergic (P2X) receptors play critical roles in bladder urothelium under physiological and pathological conditions. Aim of present study was to characterize these receptors in rat bladder urothelium and detrusor muscle using selective radioligands of [N-methyl-3H]scopolamine methyl chloride ([3H]NMS) and αβ-methylene ATP [2,8-3H]tetrasodium salt ([3H]αβ-MeATP). Similar binding parameters for each radioligand were observed in urothelium and detrusor muscle. Pretreatment with N-(2-chloroethyl)-4-piperidinyl diphenylacetate (4-DAMP mustard) mustard revealed co-existence of M2 and M3 receptors, with the number of M2 receptors being larger in the urothelium and detrusor muscle. Intravesical administration of imidafenacin and Dpr-P-4 (N → O) (active metabolite of propiverine) displayed significant binding of muscarinic receptors in the urothelium and detrusor muscle. The treatment with cyclophosphamide (CYP) or resiniferatoxin (RTX) resulted in a significant decrease in maximal number of binding sites (Bmax) for [3H]NMS and/or [3H]αβ-MeATP in the urothelium and detrusor muscle. These results demonstrated that 1) pharmacological characteristics of muscarinic and P2X receptors in rat bladder urothelium were similar to those in the detrusor muscle, 2) that densities of these receptors were significantly altered by pretreatments with CYP and RTX, and 3) that these receptors may be pharmacologically affected by imidafenacin and Dpr-P-4 (N → O) which are excreted in the urine

Photoelectric Dye, NK-5962, as a Potential Drug for Preventing Retinal Neurons from Apoptosis: Pharmacokinetic Studies Based on Review of the Evidence

NK-5962 is a key component of photoelectric dye-based retinal prosthesis (OUReP). In testing the safety and efficacy, NK-5962 was safe in all tests for the biological evaluation of medical devices (ISO 10993) and effective in preventing retinal cells from death even under dark conditions. The long-term implantation of the photoelectric dye-coupled polyethylene film in the subretinal space of hereditary retinal dystrophic (RCS) rats prevented neurons from apoptosis in the adjacent retinal tissue. The intravitreous injection of NK-5962 in the eyes of RCS rats, indeed, reduced the number of apoptotic cells in the retinal outer nuclear layer irrespective of light or dark conditions. In this study, we reviewed the in vitro and in vivo evidence of neuroprotective effect of NK-5962 and designed pharmacokinetic experiments. The in vitro IC50 of 1.7 μM, based on the protective effect on retinal cells in culture, could explain the in vivo EC50 of 3 μM that is calculated from concentrations of intravitreous injection to prevent retinal neurons from apoptosis. Pharmacokinetics of NK-5962 showed that intravenous administration, but not oral administration, led to the effective concentration in the eye of rats. NK-5962 would be a candidate drug for delaying the deterioration of retinal dystrophy, such as retinitis pigmentosa

低インスリン血症は、非糖尿病急性非代償性心不全患者において、全死亡、心血管死の独立した予後予測因子である

Background Insulin beneficially affects myocardial functions during myocardial ischemia. It increases glucose-derived ATP production, decreases oxygen consumption, suppresses apoptosis of cardiomyocytes, and promotes the survival of cardiomyocytes. Patients with chronic heart failure generally have high insulin resistance, which is correlated with poor outcomes. The role of insulin in acute decompensated heart failure (ADHF) remains unclear. This study aimed to investigate the prognostic value of serum insulin level at the time of admission for long-term outcomes in patients with ADHF. Methods and Results We enrolled 1074 consecutive patients who were admitted to our department for ADHF. Of these 1074 patients, we studied the impact of insulin on the prognosis of ADHF in 241 patients without diabetes mellitus. The patients were divided into groups according to low, intermediate, and high tertiles of serum insulin levels. Primary end points were all-cause death and cardiovascular death. During a mean follow-up of 21.8 months, 71 all-cause deaths and 38 cardiovascular deaths occurred. Kaplan-Meier analysis showed that all-cause and cardiovascular mortality was significantly higher in the low-insulin group than those in the intermediate- and high-insulin groups (log-rank P=0.0046 and P=0.038, respectively). Moreover, according to the multivariable analysis, low serum insulin was an independent predictor of all-cause and cardiovascular mortality (hazard ratio, 2.37 [95% CI, 1.24-4.65; P=0.009] and 2.94 [95% CI, 1.12-8.19; P=0.028], respectively). Conclusions Low serum insulin levels were associated with increased risk of all-cause and cardiovascular death in ADHF patients without diabetes mellitus.博士（医学）・甲第808号・令和4年3月15日© 2020 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License(https://creativecommons.org/licenses/by-nc/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes

日本における非代償性急性心不全患者の30日および90日以内の心不全再入院の発生率と臨床的意義 : NARA-HF研究より

Background: Countermeasure development for early rehospitalization for heart failure (re-HHF) is an urgent and important issue in Western countries and Japan.Methods and Results:Of 1,074 consecutive NARA-HF study participants with acute decompensated HF admitted to hospital as an emergency between January 2007 and December 2016, we excluded 291 without follow-up data, who died in hospital, or who had previous HF-related hospitalizations, leaving 783 in the analysis. During the median follow-up period of 895 days, 241 patients were re-admitted for HF. The incidence of re-HHF was the highest within the first 30 days of discharge (3.3% [26 patients]) and remained high until 90 days, after which it decreased sharply. Within 90 days of discharge, 63 (8.0%) patients were re-admitted. Kaplan-Meier analysis revealed that patients with 90-day re-HHF had worse prognoses than those without 90-day re-HHF in terms of all-cause death (hazard ratio [HR] 2.321, 95% confidence interval [CI] 1.654-3.174; P<0.001) and cardiovascular death (HR 3.396, 95% CI 2.153-5.145; P<0.001). Multivariate analysis indicated that only male sex was an independent predictor of 90-day re-HHF. Conclusions: The incidence of early re-HHF was lower in Japan than in Western countries. Its predictors are not related to the clinical factors of HF, indicating that a new comprehensive approach might be needed to prevent early re-HHF.博士（医学）・甲第735号・令和2年3月16日日本循環器学会の許諾を得て登録（2020年9月2日付）ジャーナル公式サイト（日本循環器学会HP内）：https://www.j-circ.or.jp/journal/公開サイト（J-STAGE）：https://www.jstage.jst.go.jp/browse/circj

急性心不全における退院時の尿素窒素分画排泄率の予後判定への有用性

Background Maintaining euvolemia is crucial for improving prognosis in acute decompensated heart failure (ADHF). Although fractional excretion of urea nitrogen (FEUN) is used as a body fluid volume index in patients with acute kidney injury, the clinical impact of FEUN in patients with ADHF remains unclear. This study aimed to investigate whether FEUN can determine the long-term prognosis in patients with ADHF. Methods and Results We retrospectively identified 466 patients with ADHF who had FEUN measured at discharge between April 2011 and December 2018. The primary endpoint was post-discharge all-cause death. Patients were divided into two groups according to a FEUN cut-off value of 35%, commonly used in pre-renal failure. The FEUN <35% (low-FEUN) group included 224 patients (48.1%), and the all-cause mortality rate for the total cohort was 37.1%. The log-rank test revealed that the low-FEUN group had a significantly higher rate of all-cause death compared to the FEUN equal to or greater than 35% (high-FEUN) group (P<0.001). Multivariate Cox proportional hazards model analysis revealed that low-FEUN was associated with post-discharge all-cause death, independently of other heart failure risk factors (hazard ratio, 1.467; 95% CI, 1.030-2.088, P=0.033). The risk of low-FEUN compared to high-FEUN in post-discharge all-cause death was consistent across all subgroups; however, the effects tended to be modified by renal function (threshold: 60 mL/min/1.73 m2, interaction P=0.069). Conclusions Our study suggests that FEUN may be a novel surrogate marker of volume status in patients with ADHF requiring diuretics.博士（医学）・甲第814号・令和4年3月15日Copyright © 2021 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial‐NoDerivs License(https://creativecommons.org/licenses/by-nc-nd/4.0/), which permits use and distribution in any medium, provided the original work is properly cited, the use is non‐commercial and no modifications or adaptations are made

僧帽弁閉鎖不全症を伴うまたは伴わない非代償性急性心不全患者の予後に心房細動が与える影響

Background: Atrial fibrillation (AF) and mitral regurgitation (MR) are frequently combined in patients with heart failure (HF). However, the effect of AF on the prognosis of patients with HF and MR remains unknown. Methods and Results: We studied 867 patients (mean age 73 years; 42.7% female) with acute decompensated HF (ADHF) in the NARA-HF registry. Patients were divided into 4 groups based on the presence or absence of AF and MR at discharge. Patients with severe MR were excluded. The primary endpoint was the composite of cardiovascular (CV) death and HF-related readmission. During the median follow-up of 621 days, 398 patients (45.9%) reached the primary endpoint. In patients with MR, AF was associated with a higher incidence of the primary endpoint regardless of left ventricular function; however, in patients without MR, AF was not associated with CV events. Cox multivariate analyses showed that the incidence of CV events was significantly higher in patients with AF and MR than in patients with MR but without AF (hazard ratio 1.381, P=0.036). Similar findings were obtained in subgroup analysis of patients with AF and only mild MR. Conclusions: The present study demonstrated that AF is associated with poor prognosis in patients with ADHF with mild to moderate MR, but not in those without MR.博士（医学）・甲第799号・令和3年9月29日© 2021, THE JAPANESE CIRCULATION SOCIETY This article is licensed under a Creative Commons [Attribution-NonCommercial-NoDerivatives 4.0 International] license. https://creativecommons.org/licenses/by-nc-nd/4.0

Biopharmaceutical Study on Nobiletin-Loaded Amorphous Solid Dispersion with Improved Hypouricemic Effect

The present study aimed to develop an amorphous solid dispersion of nobiletin (ASD/NOB) using hydroxypropyl cellulose-SSL (HPC-SSL) to improve the pharmacokinetic properties and hypouricemic effect of NOB. ASD/NOB was prepared by the freeze-drying method (ASD/NOB). ASD/NOB was characterized with a focus on crystallinity, dissolution, pharmacokinetic behavior, and hypouricemic action in a rat model of hyperuricemia. ASD/NOB showed significant improvement in dissolution behavior, as evidenced by a 4.4-fold higher dissolved NOB concentration than crystalline NOB at 2 h in distilled water. After the oral administration of ASD/NOB (50 mg NOB/kg) in rats, higher systemic exposure to NOB was observed with an 18-fold enhancement in oral bioavailability, and the Tmax value of orally administered ASD/NOB was 60% shorter than that of orally administered crystalline NOB. In a rat model of hyperuricemia, orally dosed ASD/NOB showed an improved hypouricemic effect by a 16% reduction in the plasma uric acid level compared with orally administered crystalline NOB. Based on these findings, ASD/NOB may be an efficacious dosage option to improve the nutraceutical potential of NOB for the treatment of hyperuricemia