Distinctive chaperonopathy in skeletal muscle associated with the dominant variant in DNAJB4.

DnaJ homolog, subfamily B, member 4, a member of the heat shock protein 40 chaperones encoded by DNAJB4, is highly expressed in myofibers. We identified a heterozygous c.270 T > A (p.F90L) variant in DNAJB4 in a family with a dominantly inherited distal myopathy, in which affected members have specific features on muscle pathology represented by the presence of cytoplasmic inclusions and the accumulation of desmin, p62, HSP70, and DNAJB4 predominantly in type 1 fibers. Both Dnajb4F90L knockin and knockout mice developed muscle weakness and recapitulated the patient muscle pathology in the soleus muscle, where DNAJB4 has the highest expression. These data indicate that the identified variant is causative, resulting in defective chaperone function and selective muscle degeneration in specific muscle fibers. This study demonstrates the importance of DNAJB4 in skeletal muscle proteostasis by identifying the associated chaperonopathy.

Nicotinic acetylcholine receptor agonist reduces acute lung injury after renal ischemia-reperfusion injury by acting on splenic macrophages in mice.

Acute kidney injury (AKI) contributes to the development of acute lung injury (ALI) via proinflammatory responses. We hypothesized that activation of a nicotinic acetylcholine receptor (nAChR), which exerts cholinergic anti-inflammatory effects on macrophages, could reduce ALI after AKI. We aimed to determine whether nAChR agonists could reduce ALI after AKI and which macrophages in the lung or spleen contribute to the improvement of ALI by nAChR agonists. We induced AKI in male mice by unilateral ischemia-reperfusion injury (IRI) with contralateral nephrectomy and administered nAChR agonists in three experimental settings: 1) splenectomy, 2) deletion of splenic macrophages and systemic mononuclear phagocytes via intravenous administration of clodronate liposomes, and 3) alveolar macrophage deletion via intratracheal administration of clodronate liposomes. Treatment with GTS-21, an α7nAChR-selective agonist, significantly reduced the levels of circulating IL-6, a key proinflammatory cytokine, and lung chemokine (C-X-C motif) ligand (CXCL)1 and CXCL2 and neutrophil infiltration, and Evans blue dye (EBD) vascular leakage increased after renal IRI. In splenectomized mice, GTS-21 did not reduce circulating IL-6 and lung CXCL1 and CXCL2 levels and neutrophil infiltration, and EBD vascular leakage increased after renal IRI. In mice depleted of splenic macrophages and systemic mononuclear phagocytes, GTS-21 treatment did not reduce lung neutrophil infiltration, and EBD vascular leakage increased after renal IRI. In mice depleted of alveolar macrophages, GTS-21 treatment significantly reduced lung neutrophil infiltration, and EBD vascular leakage increased after renal IRI. Our findings show that nAChR agonist reduces circulating IL-6 levels and acute lung injury after renal IRI by acting on splenic macrophages.NEW & NOTEWORTHY Acute lung injury associated with acute kidney injury contributes to high mortality. This study showed, for the first time, that nicotinic acetylcholine receptor agonists reduced circulating IL-6 and ALI after renal ischemia-reperfusion injury in mice. These effects of α7nAChR agonist were eliminated in both splenectomized and splenic macrophage (including systemic mononuclear phagocyte)-depleted mice but not alveolar macrophage-depleted mice. nAChR agonist could reduce ALI after AKI via splenic macrophages and provide a novel strategy in AKI.

Effects of pirenzepine on vonoprazan-induced gastric acid inhibition and hypergastrinemia.

BACKGROUND: Compared to proton pump inhibitors, vonoprazan exerts a greater inhibitory effect on gastric acid secretion and is useful for treating acid-related diseases, such as gastro-esophageal reflux disease. However, there is a problem that vonoprazan causes hypergastrinemia, which confers a risk of carcinoid tumor. A previous report demonstrated that pirenzepine, an M1 muscarinic receptor antagonist, enhances the acid inhibitory effects while suppressing hypergastrinemia induced by omeprazole. Here, we examined whether pirenzepine enhances the gastric acid inhibitory effects of vonoprazan without further increasing serum gastrin levels. METHODS: Eleven healthy volunteers were subjected to 24-h intragastric pH monitoring and serum gastrin measurements on day 7 of three different regimens: pirenzepine 75 mg alone, vonoprazan 10 mg alone, and vonoprazan 10 mg plus pirenzepine 75 mg administered in a randomized crossover fashion. RESULTS: Median pH 4 holding time ratios (range) achieved with pirenzepine 75 mg, vonoprazan 10 mg, and vonoprazan 10 mg plus pirenzepine 75 mg were 6.9% (2.4-32.8%), 88.4% (54.6-100%), and 84.2% (40.3-100%), respectively. Respective serum gastrin levels were 79 (75-210) pg/ml, 310 (110-870) pg/ml, and 170 (140-930) pg/ml. In cases with hypergastrinemia (gastrin ≥ 200 pg/ml) induced by vonoprazan 10 mg alone, concomitant treatment with pirenzepine significantly reduced serum gastrin levels from 370 to 180 pg/ml (P = 0.028). CONCLUSION: Although pirenzepine does not enhance acid inhibition, it does improve hypergastrinemia induced by vonoprazan to some extent.

IL-17A activated by Toll-like receptor 9 contributes to the development of septic acute kidney injury.

Toll-like receptor 9 (TLR9), which is activated by endogenously released mtDNA during sepsis, contributes to the development of polymicrobial septic acute kidney injury (AKI). However, downstream factors of TLR9 to AKI remain unknown. We hypothesized that IL-17A activated by TLR9 may play a critical role in septic AKI development. To determine the effects of TLR9 on IL-17A production in septic AKI, we used a cecal ligation and puncture (CLP) model in Tlr9 knockout (Tlr9KO) mice and wild-type (WT) littermates. We also investigated the pathway from TLR9 activation in dendritic cells (DCs) to IL-17A production by γδT cells in vitro. To elucidate the effects of IL-17A on septic AKI, Il-17a knockout (Il-17aKO) mice and WT littermates were subjected to CLP. We further investigated the relationship between the TLR9-IL-17A axis and septic AKI by intravenously administering recombinant IL-17A or vehicle into Tlr9KO mice and assessing kidney function. IL-17A levels in both plasma and the peritoneal cavity and mRNA levels of IL-23 in the spleen were significantly higher in WT mice after CLP than in Tlr9KO mice. Bone marrow-derived DCs activated by TLR9 induced IL-23 and consequently promoted IL-17A production in γδT cells in vitro. Knockout of Il-17a improved survival, functional and morphological aspects of AKI, and splenic apoptosis after CLP. Exogenous IL-17A administration aggravated CLP-induced AKI attenuated by knockout of Tlr9. TLR9 in DCs mediated IL-17A production in γδT cells during sepsis and contributed to the development of septic AKI.

Clinical characterization of patients with leucine-rich repeat kinase 2 genetic variants in Japan.

Variants of leucine-rich repeat kinase 2 (LRRK2) are the most common genetic cause of familial Parkinson's disease (PD). We aimed to investigate the genetic and clinical features of patients with PD and LRRK2 variants in Japan by screening for LRRK2 variants in three exons (31, 41, and 48), which include the following pathogenic mutations: p.R1441C, p.R1441G, p.R1441H, p.G2019S, and p.I2020T. Herein, we obtained data containing LRRK2 variants derived from 1402 patients with PD (653 with sporadic PD and 749 with familial PD). As a result, we successfully detected pathogenic variants (four with p.R1441G, five with p.R1441H, seven with p.G2019S, and seven with p.I2020T) and other rare variants (two with p.V1447M, one with p.V1450I, one with p.T1491delT, and one with p.H2391Q). Two risk variants, p.P1446L and p.G2385R, were found in 10 and 146 patients, respectively. Most of the patients presented the symptoms resembling a common type of PD, such as middle-aged onset, tremor, akinesia, rigidity, and gait disturbance. Dysautonomia, cognitive decline, and psychosis were rarely observed. Each known pathogenic variant had a different founder in our cohort proven by haplotype analysis. The generation study revealed that the LRRK2 variants p.G2019S and p.I2020T were derived 3500 and 1300 years ago, respectively. Our findings present overviews of the prevalence and distribution of LRRK2 variants in Japanese cohorts.

The first evidence for SLFN11 expression as an independent prognostic factor for patients with esophageal cancer after chemoradiotherapy.

BACKGROUND: Schlafen 11 (SLFN11) was recently identified as a dominant determinant of sensitivity to DNA-targeting agents including platinum-based drugs. SLFN11 also reportedly enhances cellular radiosensitivity. In this study, we examined the prognostic value of SLFN11 expression in esophageal squamous cell carcinoma (ESCC) patients treated with definitive chemoradiotherapy (dCRT), including the platinum derivative nedaplatin. METHODS: Seventy-three patients with ESCC who received dCRT were examined. SLFN11 expression was analyzed in pre-dCRT biopsies using immunohistochemistry and evaluated using a histo-score (H-score). Correlation between the H-score and overall survival was analyzed. An H-score ≥ 51 was provisionally defined as indicating high SLFN11 expression. Viability assays were performed using previously established isogenic human cell lines differentially expressing SLFN11 to test the usefulness of SLFN11 as marker of response to the dCRT regimen. RESULTS: High SLFN11 expression was independently associated with better prognosis in ESCC patients (hazard ratio = 0.295, 95% CI = 0.143-0.605, p = 0.001 for multivariate analysis). Kaplan-Meier survival curves showed that the prognostic value of high SLFN11 expression was most evident in patients at clinical stages II and III (p = 0.004). In in vitro study, SLFN11-proficient cells were highly sensitive to platinum derivatives compared to SLFN11-deficient cells. CONCLUSION: SLFN11 expression is an independent prognostic factor for ESCC patients treated with dCRT and a potential biomarker for treatment selection of ESCC. Examination of SLFN11 may be particularly useful for clinical Stage II-III patients who wish to choose dCRT (instead of surgery) to preserve esophageal function.

Prostaglandin E-major urinary metabolite versus fecal immunochemical occult blood test as a biomarker for patient with ulcerative colitis.

BACKGROUND: Prostaglandin E-major urinary metabolite (PGE-MUM) may be a novel biomarker for evaluating disease activity in ulcerative colitis (UC). We compared its usefulness to that of the fecal immunochemical occult blood test (FIT). METHODS: PGE-MUM and FIT measurements were performed of 92 urinary and fecal samples obtained from 60 patients with UC. Endoscopic activity was determined by Mayo endoscopic subscore (eMayo) and Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score. RESULTS: PGE-MUM levels and FIT results showed a significant correlation with respect to eMayo (P <  0.001 and P < 0.001, respectively), and there was a significant difference in PGE-MUM values between the groups below eMayo1 and above eMayo2 (P = 0.012). Both biomarkers were significantly correlated with the UCEIS score (P < 0.001 and P < 0.001, respectively), and the PGE-MUM values were significantly different between groups below UCEIS1 and above UCEIS2 (P = 0.012). PGE-MUM and FIT were significantly correlated with eMayo in the group with a disease duration < 5 years (P = 0.041 and P < 0.001, respectively). Although PGE-MUM and eMayo differed significantly between groups over 5 years (P = 0.012), FIT was not correlated with eMayo (P = 0.101). CONCLUSIONS: PGE-MUM is useful as a biomarker as FIT for evaluating the endoscopic activity, particularly in long-term affected patients with UC.

Dual Therapy with Vonoprazan and Amoxicillin Is as Effective as Triple Therapy with Vonoprazan, Amoxicillin and Clarithromycin for Eradication of Helicobacter pylori.

BACKGROUNDS/AIMS: Vonoprazan (VPZ) is the first clinically available potassium competitive acid blocker. This class of agents provides faster and more potent acid inhibition than proton pump inhibitors. Most strains of Helicobacter pylori are sensitive to amoxicillin. We hypothesized that dual therapy with VPZ and amoxicillin would provide the sufficient eradication rate for H. pylori infection. To evaluate this, we compared the eradication rate by the dual VPZ/amoxicillin therapy with that by the standard triple VPZ/amoxicillin/clarithromycin therapy. METHODS: Non-inferiority of the eradication rate of H. pylori by the dual therapy with VPZ 20 mg twice daily (bid) and amoxicillin 500 mg 3 times daily (tid) for 1 week to that by the triple therapy with VPZ 20 mg bid, amoxicillin 750 mg bid and clarithromycin 200 mg bid for 1 week was retrospectively studied. Propensity score matching was performed to improve comparability between 2 regimen groups. Successful eradication was diagnosed using the [13C]-urea breath test at 1-2 months after the end of eradication therapy. RESULTS: The intention-to-treat analysis demonstrated that the eradication rate by the dual therapy (92.9%; 95% CI 82.7-98.0%, 52/56) was not inferior to that of the triple therapy (91.9%; 95% CI 80.4-97.0%, 51/56; OR 1.275, 95% CI 0.324-5.017%, p = 0.728). There were no statistically significant differences in incidences of adverse events between 2 regimens. CONCLUSION: VPZ-based dual therapy (VPZ 20 mg bid and amoxicillin 500 mg tid for 1 week) provides an acceptable eradication rate of H. pylori infection without the need for second antimicrobial agents, such as clarithromycin.

Correction to: Impaired endogenous nighttime melatonin secretion relates to intrarenal renin-angiotensin system activation and renal damage in patients with chronic kidney disease.

In the original publication, an error occurred in Table 4 (B), under Nighttime group. The value of "Nighttime Log U-AGT/Cr" for model 3 (under R = 0.68) was incorrectly published as 0.11. The correct value should read as -0.31.

Comparison of effect of an increased dosage of vonoprazan versus vonoprazan plus lafutidine on gastric acid inhibition and serum gastrin.

BACKGROUND: Vonoprazan, a novel potassium-competitive acid blocker, elicits potent acid inhibition and hypergastrinemia at a dose of 20 mg. Its recommended maintenance dose for gastro-esophageal reflux disease is 10 mg, which is sometimes insufficient for preventing nocturnal acid breakthrough (NAB). Concomitant use of a histamine 2 receptor antagonist (H2RA) is effective for NAB. However, further acid inhibition by addition of H2RA has concern of hypergastrinemia again. Lafutidine (H2RA) is known to stimulate somatostatin release. AIMS: The aim of this study is to compare the levels of acid inhibition and serum gastrin attained by addition of lafutidine to vonoprazan 10 mg with levels after a dose increase of vonoprazan from 10 to 20 mg. METHODS: Thirteen healthy volunteers underwent 24-h intragastric pH monitoring and serum gastrin measurements on day 7 of three different regimens: vonoprazan 10 mg, vonoprazan 10 mg plus lafutidine 10 mg, and vonoprazan 20 mg. RESULTS: Median pH 4 holding time ratios (range) by vonoprazan 10 mg, vonoprazan 10 mg plus lafutidine 10 mg, and vonoprazan 20 mg were 82% (47-88%), 88% (76-93%), and 99% (95-100%) while those at nighttime from 10 p.m. to 8 a.m. were 94% (29-100%), 100% (95-100%), and 100%, respectively. The incidences of NAB with vonoprazan 10 mg, vonoprazan plus lafutidine, and vonoprazan 20 mg were 38, 8, and 0%, respectively. Respective serum gastrin levels were 420 (173-508), 323 (196-521), and 504 (400-812) pg/ml. CONCLUSION: Addition of lafutidine 10 mg to vonoprazan 10 mg achieved sufficient acid inhibition, especially at nighttime, without further increase of serum gastrin levels.

Melatonin ameliorates intrarenal renin-angiotensin system in a 5/6 nephrectomy rat model.

BACKGROUND: Activation of the intrarenal renin-angiotensin system (RAS) plays a critical role in the pathophysiology of chronic kidney disease (CKD) and hypertension. It has been reported that reactive oxygen species (ROS) are important components of intrarenal RAS activation. Melatonin is recognized as a powerful antioxidant, and we recently reported that impaired nighttime melatonin secretion correlates negatively with urinary angiotensinogen excretion, the surrogate marker of intrarenal RAS activity in patients with CKD. However, whether melatonin supplementation ameliorates the augmentation of intrarenal RAS in CKD has remained unknown. We aimed to clarify whether exogenous melatonin ameliorates intrarenal RAS activation via the reduction of ROS production. METHODS: 5/6 Nephrectomized (Nx) rats were used as a chronic progressive CKD model and compared with sham-operated control rats. The Nx rats were divided into untreated Nx rats and melatonin-treated Nx rats. The levels of intrarenal RAS, ROS components, and renal injury were evaluated after 4 weeks of treatment. RESULTS: Compared with the control rats, the untreated Nx rats exhibited significant increases in intrarenal angiotensinogen, angiotensin II (AngII) type 1 receptors, and AngII, accompanied by elevated blood pressure, higher oxidative stress (8-hydroxy-2'-deoxyguanosine), lower antioxidant (superoxide dismutase) activity, and increased markers of interstitial fibrosis (α-smooth muscle actin, Snail, and type I collagen) in the remnant kidneys. Treatment with melatonin significantly reversed these abnormalities. CONCLUSION: Antioxidant treatment with melatonin was shown to ameliorate intrarenal RAS activation and renal injury in a 5/6 Nx rat model.

Direct Comparison of Manganese Detoxification/Efflux Proteins and Molecular Characterization of ZnT10 Protein as a Manganese Transporter.

Manganese homeostasis involves coordinated regulation of specific proteins involved in manganese influx and efflux. However, the proteins that are involved in detoxification/efflux have not been completely resolved nor has the basis by which they select their metal substrate. Here, we compared six proteins, which were reported to be involved in manganese detoxification/efflux, by evaluating their ability to reduce manganese toxicity in chicken DT40 cells, finding that human ZnT10 (hZnT10) was the most significant contributor. A domain swapping and substitution analysis between hZnT10 and the zinc-specific transporter hZnT1 showed that residue Asn(43), which corresponds to the His residue constituting the potential intramembranous zinc coordination site in other ZnT transporters, is necessary to impart hZnT10's unique manganese mobilization activity; residues Cys(52) and Leu(242) in transmembrane domains II and V play a subtler role in controlling the metal specificity of hZnT10. Interestingly, the His → Asn reversion mutant in hZnT1 conferred manganese transport activity and loss of zinc transport activity. These results provide important information about manganese detoxification/efflux mechanisms in vertebrate cells as well as the molecular characterization of hZnT10 as a manganese transporter.

M2 polarization of murine peritoneal macrophages induces regulatory cytokine production and suppresses T-cell proliferation.

Bone-marrow-derived macrophages are divided into two phenotypically and functionally distinct subsets, M1 and M2 macrophages. Recently, it was shown that adoptive transfer of M2-polarized peritoneal macrophages reduced the severity of experimental colitis in mice. However, it is still unclear whether peritoneal macrophages possess the same ability to be polarized to cells with functionally different phenotypes and cytokine production patterns as bone-marrow-derived macrophages. To address this question, we examined the ability of peritoneal macrophages to be polarized to the M1 and M2 phenotypes and determined the specific cytokine profiles of cells with each phenotype. We showed that peritoneal macrophages, as well as bone-marrow-derived macrophages, were differentiated into M1 and M2 phenotypes following stimulation with interferon-γ (IFN-γ) and interleukin-4 (IL-4)/IL-13, respectively. Following in vitro stimulation with lipopolysaccharide, M2-polarized peritoneal macrophages predominantly expressed T helper type 2 (Th2) cytokines and regulatory cytokines, including IL-4, IL-13, transforming growth factor-ß and IL-10, whereas M1-polarized peritoneal macrophages expressed negligible amounts of Th1 and pro-inflammatory cytokines. ELISA showed that M2-polarized peritoneal macrophages produced significantly more IL-10 than M1-polarized peritoneal macrophages. Notably, M2-polarized peritoneal macrophages contributed more to the suppression of T-cell proliferation than did M1-polarized peritoneal macrophages. The mRNA expression of Th2 cytokines, including IL-4 and IL-13, increased in T-cells co-cultured with M2-polarized macrophages. Hence, our findings showed that M2 polarization of peritoneal macrophages induced regulatory cytokine production and suppressed T-cell proliferation in vitro, and that resident peritoneal macrophages could be used as a new adoptive transfer therapy for autoimmune/inflammatory diseases after polarization to the regulatory phenotype ex vivo.

Impaired endogenous nighttime melatonin secretion relates to intrarenal renin-angiotensin system activation and renal damage in patients with chronic kidney disease.

BACKGROUND: Activation of the intrarenal renin-angiotensin system (RAS) plays a critical role in the pathophysiology of chronic kidney disease (CKD) and hypertension. The circadian rhythm of intrarenal RAS activation leads to renal damage and hypertension, which are associated with diurnal blood pressure (BP) variation. The activation of intrarenal RAS following reactive oxygen species (ROS) activation, sympathetic hyperactivity and nitric oxide (NO) inhibition leads to the development of renal damage. Melatonin is a hormone regulating the circadian rhythm, and has multiple functions such as anti-oxidant and anti-adrenergic effects and enhancement of NO bioavailability. Nocturnal melatonin concentrations are lower in CKD patients. However, it is not known if impaired endogenous melatonin secretion is related to BP, intrarenal RAS, or renal damage in CKD patients. METHODS: We recruited 53 CKD patients and conducted 24-h ambulatory BP monitoring. urine was collected during the daytime and nighttime. We investigated the relationship among the melatonin metabolite urinary 6-sulphatoxymelatonin (U-aMT6s), BP, renal function, urinary angiotensinogen (U-AGT), and urinary albumin (U-Alb). RESULTS: Patients' U-aMT6s levels were significantly and negatively correlated with clinical parameters such as renal function, systolic BP, U-AGT, and U-Alb, during both day and night. Multiple regression analyses for U-aMT6s levels were performed using age, gender, renal function, and each parameter (BPs, U-AGT or U-Alb), at daytime and nighttime. U-aMT6s levels were significantly associated with U-AGT (ß = -0.31, p = 0.044) and U-Alb (ß = -0.25, p = 0.025) only at night. CONCLUSION: Impaired nighttime melatonin secretion may be associated with nighttime intrarenal RAS activation and renal damage in CKD patients.

Factors associated with healing of artificial ulcer after endoscopic submucosal dissection with reference to Helicobacter pylori infection, CYP2C19 genotype, and tumor location: Multicenter randomized trial.

BACKGROUND AND AIM: Healing speed of peptic ulcer is affected by a number of factors, including Helicobacter pylori (H. pylori) infection and intragastric pH. Acid inhibition exerted by proton pump inhibitors differs by CYP2C19 genotype. Herein, we investigated whether healing speed of artificial ulcers formed after endoscopic submucosal dissection (ESD) was influenced by H. pylori infection, CYP2C19 genotype, or other factors. METHODS: A total of 96 H. pylori-positive patients with gastric tumors scheduled for ESD were randomly assigned to receive eradication therapy for H. pylori before ESD (pre-ESD eradication) (n = 44) or after (post-ESD eradication) (n = 52). Patients received eradication therapy consisting of lansoprazole 30 mg, amoxicillin 750 mg, and clarithromycin 200 mg twice daily for 1 week. After ESD, lansoprazole 30 mg was given once daily for 8 weeks. Ulcer size was endoscopically measured on the next day and at 4 and 8 weeks after ESD. RESULTS: Mean reduction rate of artificial ulcer area in the pre-ESD eradication group was 94.7% ± 5.5% at 4 weeks, which was similar to that in the post-ESD eradication group (94.7% ± 6.7%, P = 0.987), irrespective of CYP2C19 genotype. In multivariate analyses, location of gastric tumor (middle and upper, odds ratio: 4.05, 95% CI: 1.620-10.230, P = 0.003) was a factor for 97% reduction of artificial ulcer area at 4 weeks post-ESD, but CYP2C19 genotype and H. pylori infection were not. CONCLUSION: Healing speed of ESD-induced artificial ulcer was affected by tumor location, but not by time of H. pylori eradication, resected size, or CYP2C19 genotype.

Influence of prostate stem cell antigen gene polymorphisms on susceptibility to Helicobacter pylori-associated diseases: a case-control study.

BACKGROUND: Patients with duodenal ulcer have a reduced risk of developing gastric cancer compared to those without. Recently, the prostate stem cell antigen (PSCA) rs2294008 C>T polymorphism was found to be associated with different pathogenesis of duodenal ulcer and gastric cancer developments. However, whether PSCA rs2294008 C>T polymorphism is associated with severity of gastric mucosal atrophy is unclear. We examined the influence of the PSCA rs2294008 C>T polymorphism on susceptibility to H. pylori-related diseases and the relationships between PSCA polymorphism and gastric mucosal atrophy. METHODS: PSCA rs2294008 C>T polymorphism was assessed in H. pylori-positive Japanese patients (n = 488) with noncardia gastric cancer (n = 193), gastric ulcer (n = 84), duodenal ulcer (n = 61), and atrophic gastritis (n = 150), as well as in H. pylori-negatives (n = 266). RESULTS: Frequency of PSCA rs2294008 C/C genotype in duodenal ulcer was 36.1%, which was significantly higher than those with gastric cancer (12.4%), gastric ulcer (19.0%), gastritis (10.7%), and H. pylori-negatives (19.5%) (p < .001). Compared with duodenal ulcer, having the T allele significantly increased the risk of gastric cancer (OR: 3.97, 95% CI: 2.02-7.80; p < .001), gastric ulcer (2.40, 1.13-5.10; p = .023), and gastritis (4.72, 2.26-9.86; p < .001). Mean pepsinogen (PG) I/PG II ratio in T allele carriers (2.17 ± 0.75) was significantly lower than that in C/C genotype (3.39 ± 1.27, p < .001). CONCLUSIONS: The PSCA rs2294008 C>T polymorphism is associated with differing susceptibilities to H. pylori-associated diseases. The PSCA rs2294008 C>T polymorphism may be acting through induction of gastric mucosal atrophy, finally leading to development of gastric ulcer and gastric cancer in PSCA rs2294008 T allele carriers, but not duodenal ulcer.

One-day front-loading with four doses of rabeprazole followed by a standard twice-daily regimen provides sufficient acid inhibition in extensive metabolizers of CYP2C19.

BACKGROUND: Four times daily dosing (qid) with a proton pump inhibitor can cause rapid increase in intragastric pH. We investigated the efficacy of the front-loading with rabeprazole 10 mg qid on a subsequent regimen with rabeprazole 10 mg twice daily (bid) for 7 days in extensive metabolizers (EMs) of CYP2C19. METHODS: Five EMs received three different 1-week regimens in a crossover manner as follows: (1) rabeprazole 10 mg bid for 7 days; (2) a front-loading regimen of rabeprazole (rabeprazole 10 mg qid on day 0 and bid on days 1 to 7); and (3) rabeprazole 10 mg qid for 7 days. Five intermediate metabolizers (IMs) and four poor metabolizers (PMs) received rabeprazole 10 mg bid regimen only. Twenty-four-hour intragastric pH-monitorings were performed on days 1, 4, and 7. Area under the intragastric pH-time curves (AUCs) from days 1 to 7 was calculated using 24-h median intragastric pHs on days 1, 4, and 7. RESULTS: Twenty-four-hour intragastric pHs in the front-loading group on days 1, 4, and 7 were 5.1, 4.9, and 5.1, respectively. The median AUC with front-loading in EMs (34.4, pH·day) was significantly higher than that in EMs with rabeprazole 10 mg bid (30.74, p = 0.043). No statistically significant differences in median AUCs were noted among front-loading in EMs, rabeprazole 10 mg qid in EMs (37.2), rabeprazole 10 mg bid in IMs (37.3), and PMs (39.4). CONCLUSIONS: The one-day front-loading regimen of rabeprazole 10 mg qid provided sufficient acid inhibition for 7 days, even in CYP2C19 EMs.

Potent Gastric Acid Inhibition Over 24 Hours by 4-Times Daily Dosing of Esomeprazole 20 mg.

BACKGROUND: When administered at a standard dose, proton pump inhibitors (PPIs) do not always provide sufficient acid inhibition for all subjects, particularly in extensive metabolizers (EMs) of CYP2C19. Whether esomeprazole at a dose of 20 mg four times daily dosing (q.i.d.) can attain sufficient acid inhibition throughout 24 h in EMs remains unclear. We therefore investigated the efficacy of esomeprazole q.i.d. for acid inhibition. METHODS: In a randomized cross-over design, 30 Helicobacter pylori-negative healthy young Japanese volunteers received esomeprazole at a dose of 20 mg two times a day (b.i.d.) or q.i.d. for 7 days. A pH monitoring was conducted before the trial as a control and on day 7 of both regimens. RESULTS: Median pH values in the q.i.d. regimen were significantly higher than those with the b.i.d. regimen in EMs (b.i.d.: 5.3, q.i.d.: 6.6, p = 0.022), intermediate metabolizer (IM) (b.i.d.: 5.5, q.i.d.: 6.8, p = 0.005) and poor metabolizer (PM) (b.i.d.: 6.2, q.i.d.: 7.0, p = 0.047), respectively. Median pH with the b.i.d. regimen differed significantly by CYP2C19 genotypes (p = 0.004), but not the q.i.d. regimen (p = 0.384). CONCLUSION: Esomeprazole q.i.d. achieved potent acid inhibition in all Helicobacter pylori-negative subjects, irrespective of CYP2C19 genotype, which might be one of the rescue regimens for patients' refractory to PPI treatment.

Disturbed circadian rhythm of the intrarenal renin-angiotensin system: relevant to nocturnal hypertension and renal damage.

BACKGROUND: The intrarenal renin-angiotensin system (RAS) plays an important role in the development of hypertension and renal damage. Disruption of diurnal blood pressure (BP) variation is an additional risk factor for renal damage. However, little is known regarding whether intrarenal RAS circadian rhythm exists or if it influences the disruption of diurnal BP and renal damage. METHODS: We investigated the circadian rhythm of urinary angiotensinogen (U-AGT) that reflects intrarenal RAS activity in 14 individuals without chronic kidney disease (CKD) and 36 CKD patients classified according to circadian BP rhythms. RESULTS: BP values were higher during the daytime than during the nighttime in both individuals without CKD and CKD patients. U-AGT levels were not different between the daytime and nighttime in individuals without CKD, but were significantly higher in the daytime in CKD patients (log U-AGT/creatinine: daytime, 2.39 ± 0.99; nighttime, 2.24 ± 1.06; p = 0.001). Furthermore, in CKD patients showing a riser pattern of circadian BP, U-AGT levels did not decrease during the nighttime compared with those in the daytime (log U-AGT/creatinine: daytime, 2.51 ± 0.65; nighttime, 2.52 ± 0.71; p = 0.78). Circadian fluctuation of albuminuria and proteinuria occurred parallel to that of the U-AGT levels. U-AGT levels were significantly and positively correlated with the levels of BP and circadian fluctuation of U-AGT was correlated with diurnal BP changes. CONCLUSION: These data suggest that the circadian rhythm of intrarenal RAS activation may lead to renal damage and hypertension, which are associated with diurnal BP variation.