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Post-myocardial infarction ventricular septal rupture (PIVSR) is becoming increasingly rare in the percutaneous coronary intervention era; however, the mortality rates remain high. Surgical repair is the gold standard treatment for PIVSR but is associated with surgical difficulty and high mortality. Therefore, the timing of surgery is controversial (i.e. either undertake emergency surgery or wait for resolution of organ failure and scarring of the infarcted area). Although long-term medical management is usually ineffective, several mechanical circulatory support (MCS) devices have been used to postpone surgery to an optimal timing. Recently, in addition to venous arterial extracorporeal membrane oxygenation (VA-ECMO), new MCS devices, such as Impella (Abiomed Inc., Boston, MA, USA), have been developed. Impella is a pump catheter that pumps blood directly from the left ventricle, in a progressive fashion, into the ascending aorta. VA-ECMO is a temporary MCS system that provides complete and rapid cardiopulmonary support, with concurrent hemodynamic support and gas exchange. When left and right heart failure and/or respiratory failure occur in cardiogenic shock or PIVSR after acute myocardial infarction, ECpella (Impella and VA-ECMO) is often introduced, as it can provide circulatory and respiratory assistance in a shorter period. This review outlines the basic concepts of MCS in PIVSR treatment strategies and its role as a bridge device, and discusses the efficacy and complications of ECpella therapy and the timing of surgery.

Drug disposition after topical application to the skin has not been fully elucidated, especially after repeated application. We conducted a clinical trial to evaluate the pharmacokinetics in the stratum corneum of healthy adults after repeated application of lanoconazole cream as a model drug. We applied 25 mg of 1% lanoconazole cream onto the pre-specified areas on the participants' back once daily for 5 days. The stratum corneum was sampled twice on each study day using a standardized tape-stripping method, and the amount of lanoconazole contained in the samples was quantified using the tandem mass spectrometry method. The obtained data were used to evaluate lanoconazole pharmacokinetics in the stratum corneum. The amount of lanoconazole in the stratum corneum after once daily repeated administration reached a steady state on day 3, and it was eliminated from the stratum corneum with a half-life of approximately 11 h after discontinuing application.

Background: Monocarboxylate transporter 9 (MCT9), an orphan transporter member of the solute carrier family 16 (SLC16), possibly reabsorbs uric acid in the renal tubule and has been suggested by genome-wide association studies to be involved in the development of hyperuricemia and gout. In this study we investigated the mechanisms regulating the expression of human (h) MCT9, its degradation, and physiological functions. Methods and Results: hMCT9-FLAG was stably expressed in HEK293 cells and its degradation, intracellular localization, and urate uptake activities were assessed by pulse-chase analysis, immunofluorescence, and [14C]-urate uptake experiments, respectively. hMCT9-FLAG was localized on the plasma membrane as well as in the endoplasmic reticulum and Golgi apparatus. The proteasome inhibitors MG132 and lactacystine increased levels of hMCT9-FLAG protein expression with enhanced ubiquitination, prolonged their half-life, and decreased [14C]-urate uptake. [14C]-urate uptake was increased by both heat shock (HS) and the HS protein inducer geranylgeranylacetone (GGA). Both HS and GGA restored the [14C]-urate uptake impaired by MG132. Conclusions: hMCT9 does transport urate and is degraded by a proteasome, inhibition of which reduces hMCT9 expression on the cell membrane and urate uptake. HS enhanced urate uptake through hMCT9.

Inflammation induced by urate deposition in joints causes gout. Healthy individuals maintain serum levels of urate by balancing urate production/excretion, whereas a production/excretion imbalance increases urate levels. Hyperuricemia is diagnosed when the serum urate level is continuously above 7 mg/dl as the solubility limit, and urate accumulates in the kidneys and joints. Because hyperuricemia increases the risk of gout, therapies aim to eliminate urate deposition to prevent gouty arthritis and kidney injury.This review discusses the mechanism underlying hyperuricemia with respect to urate production and urate transport, along with urate-lowering therapeutics, including urate synthesis inhibitors, uricolytic enzymes, and uricosuric agents. The authors asses published data on relevant commercial therapy development projects and clinical trials.Available treatment options for hyperuricemia are limited. Allopurinol, a urate synthesis inhibitor, is generally administered at a reduced dosage to patients with renal impairment. Some URAT1 inhibitors have an unfavorable side effect profile. A promising strategy for treatment is the use of uricosuric agents that inhibit transporters (e.g. URAT1, URATv1/GLUT9, OAT10) which reabsorb urate from the urine.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a condition in which an organic thrombus remains in the pulmonary artery (PA) even after receiving anticoagulation therapy for more than 3 months and is complicated by pulmonary hypertension (PH), leading to right-sided heart failure and death. CTEPH is a progressive pulmonary vascular disease with a poor prognosis if left untreated. The standard treatment for CTEPH is pulmonary endarterectomy (PEA), which is usually performed only in specialized centers. In recent years, balloon pulmonary angioplasty (BPA) and drug therapy for CTEPH have also shown good results. This review discusses the complex pathogenesis of CTEPH and presents the standard of care, PEA, as well as a new device called BPA, which is showing remarkable progress in efficacy and safety. Additionally, several drugs are now demonstrating established evidence of efficacy in treating CTEPH.

Aims In addition to potentially progressing to either cirrhosis or hepatocellular carcinoma, non-alcoholic steatohepatitis (NASH) is currently the leading indication for liver transplantation. Nintedanib has been clinically used to treat idiopathic pulmonary fibrosis for many years, but its effects in an animal model of NASH have not been tested. The purpose of this study was to evaluate the effects of nintendanib on NASH in choline-deficient, l -amino acid-defined, high-fat diet (CDAHFD)-fed mice. Main methods Male C57BL/6 mice were fed a CDAHFD for 6 weeks to induce NASH with liver fibrosis, and they were administered nintedanib (60 mg/kg/day) or distilled water orally in the last 2 weeks of the feeding period. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), triglyceride, and non-esterified fatty acids concentrations were measured. Serum cytokeratin 18 fragment (CK18) was detected using ELISA. Liver tissue sections from mice were stained with hematoxylin-eosin and Masson's trichrome to assess the level of steatohepatitis and fibrosis. Key findings CDAHFD-fed mice exhibited higher serum ALT, AST, and ALP levels compared with Control mice. A significant increase in the serum CK18 level was observed in the NASH group compared with the Control group. CDAHFD feeding also enhanced steatohepatitis and hepatic fibrosis pathological features, which were reduced after nintedanib treatment. Significance Nintedanib exerted anti-inflammatory and anti-fibrotic effects in CDAHFD-induced NASH mice.

Background Intracellular uric acid is known to increase the protein level and channel current of atrial Kv1.5; however, mechanisms of the uric acid-induced enhancement of Kv1.5 expression remain unclear. Methods and Results: The effects of uric acid on mRNA and protein levels of Kv1.5, as well as those of Akt, HSF1 and Hsp70, in HL-1 cardiomyocytes were studied by using qRT-PCR and Western blotting. The uptake of uric acid was measured using radio-labeled uric acid. The Kv1.5-mediated channel current was also measured by using patch clamp techniques. Uric acid up-taken by HL-1 cells significantly increased the level of Kv1.5 proteins in a concentration-dependent manner, with this increase abolished by an uric acid transporter inhibitor. Uric acid slowed degradation of Kv1.5 proteins without altering its mRNA level. Uric acid enhanced phosphorylation of Akt and HSF1, and thereby increased both transcription and translation of Hsp70; these effects were abolished by a PI3K inhibitor. Hsp70 knockdown abolished the uric acid-induced increases of Kv1.5 proteins and channel currents. Conclusions Intracellular uric acid could stabilize Kv1.5 proteins through phosphorylation of Akt and HSF1 leading to enhanced expression of Hsp70.

This study was designed to investigate the effects of uric acid on vascular endothelial function in measurements carried out either at the bedside or the laboratory bench. First, we performed reactive hyperemia peripheral arterial tonometry using an EndoPAT 2000 device and measured serum uric acid levels in 92 outpatients with hypertension. The reactive hyperemia index (RHI) showed no correlation with serum uric acid level (R = -0.125, P = 0.235) in either overall patients or in a high-risk group of 51 patients with complications such as cardiovascular and cerebrovascular diseases, chronic kidney disease, and/or diabetes (R = -0.025, P = 0.860). However, in the remaining 41 patients in the low-risk group, RHI correlated negatively with serum uric acid level (R = -0.335, P = 0.032). Multiple regression analysis showed that serum uric acid level predicted RHI (R = -0.321, P = 0.043) in the low-risk group independent of age, body mass index, systolic blood pressure, and low density lipoprotein-cholesterol level. We then performed an in-vitro study using the WST-8 assay in human umbilical vein endothelial cells, which showed that hypoxic conditions reduced cell viability. Treatment with uric acid caused a further reduction in cell viability, while ascorbic acid improved viability. Using Western blot analysis, we observed that uric acid reduced endothelial nitric oxide synthase phosphorylation during hypoxic conditions. Serum uric acid level is associated with peripheral vascular endothelial function in patients with low-risk hypertension and uric acid could directly impair endothelial function under hypoxic conditions. These results are relevant to the interventional studies examining the cardiovascular protective effect of hypouricemic agents.

We evaluated the effects of anticholinergic drugs principally used for the therapy of overactive bladder (OAB) on the activity of P-glycoprotein, an efflux transport protein, in Caco-2 cells. The time-dependent changes in the fluorescence of residual rhodamine 123, a P-glycoprotein activity marker, in the apical region of Caco-2 cells were measured in the presence of anticholinergic drugs using time-lapse confocal laser scanning microscopy. The effect of anticholinergic drugs on human P-glycoprotein ATPase activity was also measured. The fluorescence of residual rhodamine 123 in untreated Caco-2 cells decreased over time. The gradual decrease in the fluorescence was significantly inhibited by treatment with cyclosporine A, darifenacin, and trospium. In contrast, oxybutynin, N-desethyl-oxybutynin (DEOB), propiverine, and its active metabolites (M-1, M-2), imidafenacin, solifenacin, or tolterodine had little effect on the efflux of rhodamine 123. P-Glycoprotein ATPase activity was increased by darifenacin. Darifenacin and trospium reduced the rhodamine 123 transfer across the apical cell membrane. These data suggest that darifenacin and trospium interact with P-glycoprotein. Additionally, darifenacin influenced P-glycoprotein ATPase activity. These results suggest that darifenacin may be a substrate of P-glycoprotein. This study is the first paper to test simultaneously the effects of 10 anticholinergic drugs used currently for the therapy of OAB, on the P-glycoprotein.

The purpose of this study was to create novel urate under-excretion animal models using pyrazinamide and to evaluate whether dihydropyridine calcium channel blockers (CCBs) have uricosuric effects in vivo.Adult male ICR mice were treated with pyrazinamide, vehicle (dimethyl sulfoxide: DMSO), or tap water. Thirty minutes later, pyrazinamide-treated mice were given benzbromarone, losartan, nilvadipine, nitrendipine, nifedipine or azelnidipine. Six hours after the second administration, urine (by urinary bladder puncture) and plasma were collected to measure uric acid and creatinine levels, and fractional excretion of uric acid (FEUA) and creatinine clearance (Ccr) were calculated and evaluated. There was no significant difference in the levels of plasma uric acid, plasma creatinine, Ccr, urinary N-acetyl-β-d-glucosaminidase (NAG) and urinary NAG-creatinine ratio between water, DMSO, and pyrazinamide-treated mice. But the FEUA of pyrazinamide-treated mice was significantly lower than water mice. The FEUA was significantly higher in mice taking the dihydropyridine CCBs (nilvadipine, nitrendipine, nifedipine, and high-dose azelnidipine) than in pyrazinamide-treated mice. There was no significant difference in Ccr.Thus, a novel animal model created with PZA administration was useful as a urate under-excretion animal model that was probably URAT1-mediated, and the uricosuric effects of dihydropyridine CCBs were confirmed in vivo. Keywords: Uric acid, Urate, Fractional excretion of uric acid, Urate under-excretion animal model, Calcium channel blocker

An antioxidant effect of the flavonoids in food has been widely noticed as it may prevent the oxidative stress-associated chronic diseases including ischemic heart disease and diabetes mellitus. Flavonoids which are distributed widely in plants are classified into a flavonol, flavanol, flavanone, flavone, isoflavone and anthocyanidin. Of which quercetin, a flavanol, presents ubiquitously as a quercetin glycoside. Most of flavonoids including quercetin which are absorbed in the intestine enter the circulatory blood after they are converted to the conjugated metabolites, and are rapidly eliminated by the kidney into urine. Most studies have focused on the intestinal absorption of the flavonoids which may regulate a physiological function and efficacy of the flavonoids, however their elimination routes at the kidney have remained unknown. This study aims to clarify molecular mechanisms of renal elimination of the flavonoids by inhibiting their transports in view of regulation of their bioavailability in the body. By using the cells stably expressing organic anion transporters 1 （OAT1） and 3 （OAT3） which had been previously established by us, the inhibitory effects of extracellular flavonoids （0.01, 0.1, 1, 10, 100 uM） on the uptake of representative substrates,para-aminohippuric acid（PAH）for OAT1 and estrone sulfate（ES）for OAT3 were investigated. In results, the flavonoids including quercetin, kaempterol, apigenin, luteolin and naringenin inhibited the OAT1 and OAT3-mediated organic anion transports. Inhibitions by genistein and daidzein were only shown in the OAT1 transport and rutin neither inhibited the transport of OAT1 nor OAT3. OAT1 and OAT3 which exist at the basolateral side of the renal proximal tubules are known as the opening site for the uptake of organic anions and the present results suggested OATs may be a renal elimination route for the circulatory flavonoids.

An integrated analysis was performed with data from 4 phase 2 and phase 3 studies of tofogliflozin in which patients with type 2 diabetes mellitus received the sodium‐glucose cotransporter 2 inhibitor tofogliflozin for up to 24 weeks. Sex differences, baseline haemoglobin A1c (HbA1c) and serum uric acid (UA) levels, and log10‐transformed urinary N‐acetyl‐β‐D‐glucosaminidase ratio were significantly correlated with the reduction in serum UA levels at both 4 and 24 weeks in multivariate analysis (respectively, P 8.6%) and lowest in the group with the lowest baseline HbA1c level (quartile 1; HbA1c ≤ 7.4%). The decrease in serum UA levels was greatest in the quartile 1 group and lowest in the quartile 4 group. In most groups, the maximum decrease in serum UA levels was seen in the first 4 weeks, while the maximum decrease in HbA1c was seen at week 24. Thus, serum UA levels were significantly decreased in patients with moderate HbA1c levels.

Background Ischemia/reperfusion (I/R) injury triggers cardiac dysfunctions via creating reactive oxygen species (ROS). Because xanthine oxidase (XO) is one of the major enzymes that generate ROS, inhibition of XO is expected to suppress ROS-induced I/R injury. However, it remains unclear whether XO inhibition really yields cardioprotection during I/R. The protective effects of the XO inhibitors, topiroxostat and allopurinol, on cardiac I/R injury were evaluated.Methods and Results:Using isolated rat hearts, ventricular functions, occurrence of arrhythmias, XO activities and thiobarbituric acid reactive substances (TBARS) productions and myocardial levels of adenine nucleotides before and after I/R, and cardiomyocyte death markers during reperfusion, were evaluated. Topiroxostat prevented left ventricular dysfunctions and facilitated recovery from arrhythmias during I/R. Allopurinol and the antioxidant, N-acetylcysteine (NAC), exhibited similar effects at higher concentrations. Topiroxostat inhibited myocardial XO activities and TBARS productions after I/R. I/R decreased myocardial levels of ATP, ADP and AMP, but increased that of xanthine. While topiroxostat, allopurinol or NAC did not change myocardial levels of ATP, ADP or AMP after I/R, all of the agents decreased the level of xanthine. They also decreased releases of CPK and LDH during reperfusion. Conclusions Topiroxostat showed protective effects against I/R injury with higher potency than allopurinol or NAC. It dramatically inhibited XO activity and TBARS production, suggesting suppression of ROS generation.

Background Pilsicainide, classified as a relatively selective Na + channel blocker, also has an inhibitory action on the rapidly-activating delayed-rectifier K + current ( I Kr ) through human ether-a-go-go-related gene (hERG) channels. We studied the effects of chronic exposure to pilsicainide on the expression of wild-type (WT) hERG proteins and WT-hERG channel currents, as well as on the expression of mutant hERG proteins, in a heterologous expression system. Methods HEK293 cells stably expressing WT or mutant hERG proteins were subjected to Western blotting, immunofluorescence microscopy and patch-clamp experiments. Results Acute exposure to pilsicainide at 0.03–10μM influenced neither the expression of WT-hERG proteins nor WT-hERG channel currents. Chronic treatment with 0.03–10μM pilsicainide for 48h, however, increased the expression of WT-hERG proteins and channel currents in a concentration-dependent manner. Chronic treatment with 3μM pilsicainide for 48h delayed degradation of WT-hERG proteins and increased the channels expressed on the plasma membrane. A cell membrane-impermeant pilsicainide derivative did not influence the expression of WT-hERG, indicating that pilsicainide stabilized the protein inside the cell. Pilsicainide did not influence phosphorylation of Akt (protein kinase B) or expression of heat shock protein families such as HSF-1, hsp70 and hsp90. E4031, a chemical chaperone for hERG, abolished the pilsicainide effect on hERG. Chronic treatment with pilsicainide could also increase the protein expression of trafficking-defective mutant hERG, G601S and R752W. Conclusions Pilsicainide penetrates the plasma membrane, stabilizes WT-hERG proteins by acting as a chemical chaperone, and enhances WT-hERG channel currents. This mechanism could also be applicable to modulations of certain mutant-hERG proteins.

Although risk factors for acute coronary syndrome (ACS) and atherothrombotic cerebral infarction (ACI) are common, it is unknown if the risk factors for these two conditions are similar. The purpose of our study was to elucidate differences in carotid artery atherosclerotic features between ACS and ACI. We measured carotid artery ultrasound-based atherosclerotic parameters in 61 ACS and 33 ACI patients. In the ACS patients, 31 had single-vessel coronary artery disease (SVD) and 30 had multivessel coronary artery disease (MVD). The maximum intima–media thickness (IMT) of the common carotid artery was higher in ACS patients with MVD than in ACS patients with SVD (P

This study evaluated the utility of combination of digoxin (0.25 mg) and rosuvastatin (5 mg) as a new transporter (P‐glycoprotein/breast cancer resistance protein/organic anion‐transporting polypeptide (OATP)1B1/OATP1B3) probe cocktail (Oita combination) for drug–drug interaction (DDI) studies by demonstrating lack of DDI of digoxin on the pharmacokinetics (PKs) of rosuvastatin, as it was already known that rosuvastatin did not affect digoxin PK. This was an open‐label, two‐period study in which the primary end points were the geometric mean ratio (GMR) of the area under the plasma rosuvastatin concentration‐time curve from time zero to last (AUC last) after rosuvastatin administration combined with digoxin to that after rosuvastatin administration alone and its 90% confidence interval (CI). As the GMR of AUC last was 0.974 and its 90% CI was 0.911–1.042, it was judged that digoxin does not affect rosuvastatin PK. Results of this study have rationalized utility of the Oita combination as a transporter probe cocktail for clinical DDI studies.

The impact of obstructive sleep apnoea on heart failure with preserved ejection fraction is unknown.Fifty-eight patients who had heart failure with a left ventricular ejection fraction; ≥50% underwent a sleep study. Brain natriuretic peptide (BNP) levels were determined at enrolment and at one, six, 12 and 36 months after enrolment.Obstructive sleep apnoea was found in 39 patients (67%), and they were all subsequently treated with continuous positive airway pressure. Echocardiography at admission showed that E/E' tended to be higher in the 39 patients with, than in the 19 patients without, obstructive sleep apnoea (15.0±3.6 vs 12.1±1.9, respectively, P=0.05). The median BNP levels at enrolment were similar in patients with and without obstructive sleep apnoea [median (interquartile range): 444 (233-752) vs 316 (218-703) pg/ml]. Although BNP levels decreased over time in both groups, the reduction was less pronounced in patients with obstructive sleep apnoea (P0.05). Consequently, BNP levels were higher in patients with sleep apnoea at six months, [221 (137-324) vs 76 (38-96) pg/ml, P0.05], 12 months [123 (98-197) vs 52 (38-76) pg/ml, P0.05] and 36 months [115 (64-174) vs 56 (25-74) pg/ml, P0.05].Obstructive sleep apnoea, even when treated appropriately, may worsen long-term cardiac function and outcomes in patients who have heart failure with preserved ejection fraction.

降圧薬などいくつかの薬剤は本来の薬理作用とは別に尿酸降下作用を持つものがあり,水溶性ヨード系造影剤もその一つでiodipamideやdiatrizoateでの尿酸排泄亢進が報告されていた.長らく不明のままであった腎尿酸輸送機構の分子実体は2002年の腎尿細管尿酸トランスポーターURAT1(Urate Transporter 1)の分子同定によりその理解が飛躍的に進んだ.本研究ではURAT1と水溶性造影剤のiodipamideおよびdiatrizoateの相互作用を検討することで,その尿酸排泄促進作用の分子機序の解明を目的とする.URAT1の尿酸輸送活性の測定にはURAT1安定発現HEK293細胞(HEK-URAT1)細胞を用いた.IodipamideはHEK-URAT1細胞でのRI標識尿酸取込みを著明に阻害した(IC_:1.19±0.08?μM)のに対し,diatrizoateは1?mMまでの範囲では50%以上の阻害作用を示さなかった.1?mMまでのiodipamideはHEK-URAT1細胞の生存率に影響を与えなかった.IodipamideによるURAT1媒介尿酸輸送への阻害作用のキネティクス解析の結果,その阻害は競合阻害であり,阻害定数Ki値は11.03?μMであった.以上より,iodipamideは尿酸トランスポーターURAT1と相互作用をすることを初めて確認できた.このことからiodipamideは細胞外からURAT1の尿酸結合部位に結合し,競合して阻害を行うことで,腎尿細管の経上皮性尿酸再吸収を抑制し,ひいては血清尿酸値を低下させるものと考えられた., Drug-induced hypouricemia has been found in several drugs such as probenecid, benzbromarone and angiotensin II receptor blocker(ARB)losartan. Xray contrast agents such as iodipamide and diatrizoate, used for the intravenous cholangiography and excretory urography, were reported to have uricosuric effct beside their original action. After the molecular identification of renal apical urate transporter URAT1 as an entrance of urate into the epithelial cells of proximal tubules, this protein is thought to be major determinant for renal reabsorption of urate that affect the blood urate levels in human. The purpose of this study is to examine whether iodipamide and diatrizoate act on URAT 1 . In URAT 1 -stably expressing HEK293(HEK-URAT1)cells, iodipamide inhibited [^C] urate uptake dose-dependently(IC_ , 1.19±0.08 μM), while diatrizoate did not. Up to the concentration of 1 mM, iodipamide incubation for 24 hr did not affect the viability of HEK293-URAT1 cells. Lineweaver-Burk plot of the kinetic analysis by URAT1-mediated urate uptake with or without iodipamide indicated that its interaction occurs in a competitive manner(Ki:11.03 μM). These results suggest that uricosuric effect of iodipamide can be explained by the interaction of iodipamide with urate-binding site of URAT1, and the inhibition of urate reabsorption from extracellular side by iodipamide causes uricosuria leading to induce hypouricemia.

Hyperuricemia has recently been recognized as one of the risk factors for cardiovascular diseases. Some calcium channel blockers(CCBs), commonly used in the treatment of hypertension, have been reported to decrease serum urate level. Here, we tried to elucidate the molecular mechanism of the urate-lowering effects of CCBs. We performed [^C]urate uptake in cells stably expressing human urate transporter 1, a major contributor of renal urate reabsorption and a major target of uricosuric drugs such as benzbromarone and losartan(HEK-URAT1), together with mock(HEK-mock)cells to analyze the uricosuric action of CCBs. We also measured the activity of human xanthine oxidase(XO)to determine whether CCBs have inhibitory effects on urate production. The CCBs tested were nifedipine, nilvadipine, nitrendipine, benidipine, nisoldipine, nicardipine, efonidipine, amlodipine, azelnidipine, verapamil and diltiazem. We found for the first time that at least seven CCBs in the dihydropyridine subgroup interacted with URAT1-mediated urate uptake in HEK-URAT1 cells. Among these CCBs, nifedipine, nilvadipine and nitrendipine strongly inhibited URAT1-mediated urate uptake. Their IC_s were 15.8, 0.018 and 0.40?μM, respectively. In contrast, urate production mediated by XO was weakly inhibited by nifedipine and nisoldipine. In summary, URAT1 interacted with various CCBs differently, whereas XO, a major enzyme for urate production in the liver, did not interact with most of CCBs. Although CCBs were not excreted from the urine basically, their urate-lowering effects may be associated with the inhibition of renal urate reabsorption mediated by renal urate transporters such as URAT1 with their metabolites, and the results for structure-activity information in this study will provide a clue for developing new uricosuric drugs targeting URAT1.

_L-Carnitine is an essential component of mitochondrial fatty acid b-oxidation in the muscle and may control the acetyl moiety levels in the brain for acetylcholine synthesis. Carnitine transporter 1(CT1)is the high affinity _L-carnitine transporter whose localization was observed in the kidney, testis, liver, skeletal muscle and brain. To clarify the molecular mechanism of carnitine transport, we sought to find the interacting protein that may be related to the transport function of CT1. Using the intracellular C-terminal region of rat CT1 containing PDZ(PSD95/DLG/ZO-1)motif as bait, we performed the yeast two-hybrid screening against rat brain cDNA library. Thirty two positive clones were obtained from the 2.7×10^7 clones screened. One of them was PDZ domain-containing protein Lin-7. We found that Lin-7 interacts specifically with C-termini of CT1:deletion and mutation of the CT1 C-terminal PDZ-motif abolished the interaction with Lin-7 in the yeast two-hybrid assay. In addition, a PDZ domain within Lin-7 associates with the CT1 C-terminal. The association of CT1 with Lin-7 enhanced _L-carnitine transport activities in HEK293 cells although there is no statistical significance. Coexpression of Lin-7 and CT1 is identified in motor neurons of the spinal cord ventral horn together with Lin-2, a binding partner of Lin-7 known to assemble proteins involved in synaptic vesicle exocytosis and synaptic junctions. Therefore, Lin-7 interacts with CT1 and may regulate their subcellular distribution or function in central nervous system.

Diabetes mellitus is a lifestyle-related disease that is characterized by inappropriate or diminished insulin secretion. Ex vivo pharmacological studies of hypoglycemic agents are often conducted using perfused pancreatic preparations. Pancreas preparations for organ bath experiments do not require cannulation and are therefore less complex than isolated perfused pancreas preparations. However, previous research has generated almost no data on insulin secretion from pancreas preparations using organ bath preparations. The purpose of this study was to investigate the applicability of isolated rat pancreas preparations using the organ bath technique in the quantitative analysis of insulin secretion from β-cells. We found that insulin secretion significantly declined during incubation in the organ bath, whereas it was maintained in the presence of 1 µM GLP-1. Conversely, amylase secretion exhibited a modest increase during incubation and was not altered in the presence of GLP-1. These results demonstrate that the pancreatic organ bath preparation is a sensitive and reproducible method for the ex vivo assessment of the pharmacological properties of hypoglycemic agents.

A 58-year-old woman with a past medical history of a carotid body tumor, resected 4 months prior to presentation, was admitted to our hospital for treatment of a cardiac tumor that was identified on post-operative echocardiography and chest computed tomography. The cardiac tumor was surgically removed and identified pathologically as a paraganglioma, similarly to the carotid body tumor. Genetic analysis of both tumors identified a non-synonymous mutation in the succinate dehydrogenase (SDH) gene D, Exon4, c.320T>C, p.Leu107Pro showing co-segregation with paternal transmission and maternal imprinting among family members. This novel mutation appears to be the cause of familial paraganglioma in this patient.

Background: Although urate impaired the endothelial function, its underlying mechanism remains unknown. We hypothesized that urate impaired nitric oxide (NO) production in human umbilical vein endothelial cells (HUVECs) via activation of uric acid transporters (UATs). Purpose and method: In the present study, we studied effects of urate on NO production and eNOS protein expression in HUVEC cells in the presence and absence of urate lowering agents using molecular biological and biochemical assays. Results: HUVECs expressed the 4 kinds of UATs, URATv1, ABCG2, MRP4 and MCT9. Exposure to urate at 7 mg/dl for 24 h significantly reduced production of NO. Pretreatment with benzbromarone, losartan or irbesartan normalized NO production. The same exposure resulted in dephosphorylation of endothelial NO synthase (eNOS) in HUVECs. Again pretreatment with benzbromarone, losartan or irbesartan abolished this effect. Conclusion: Urate reduced NO production by impaired phosphorylation of eNOS in HUVEC via activation of UATs, which could be normalized by urate lowering agents.

Boron neutron capture therapy (BNCT) is a biochemically-targeted radiotherapy based on the nuclear capture and fission reactions that occur when boron-10 is irradiated with low energy thermal neutrons to yield high linear energy transfer alpha particles and recoiling lithium-7 nuclei with path-length less than 10 μm.It has been focused to use on the treatment of brain, skin, head and neck cancers. 4-Boronophenylalanine (BPA), a BNCT delivery agent, has been used in clinical field but its transport mechanism into the tumor lesion was not clear. It is known that L-type amino acid transporters, LAT1 and LAT3 are highly expressed in various types of cancer whereas LAT2 and LAT4 are expressed in normal tissues. The LAT1-selective compound(s) might be the ideal delivery agents for BNCT to obtain the specific accumulation in cancer tissue and reduce adverse effect on normal tissue. In this study we identify the transport of BPA by L-type amino acid transporters using Xenopus oocyte expression system and LC/MS-MS...

Introduction: Zotepine and chlorprothixene are antipsychotic drugs, and they have a broad therapeutic effect on patients with schizophrenia. Zotepine and chlorprothixene have been reported to decre...