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1.
Respir Investig ; 62(5): 914-921, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39126825

ABSTRACT

BACKGROUND: Respiratory syncytial virus (RSV) is a leading cause of acute respiratory illness, with severe outcomes in older adults. Information on the prevalence, hospitalization rate, and impact on the health-related quality of life (HRQoL) of RSV in older adults with acute respiratory infections (ARI) in outpatient settings in Japan is limited. METHODS: This multi-center epidemiological study included outpatients aged ≥60 years presenting with ARI between August 2021 and February 2023. Nasal and throat swabs were collected and tested by reverse transcription polymerase chain reaction (RT-PCR). The prevalence of RT-PCR-confirmed RSV (cRSV)-ARI, cRSV-lower respiratory tract disease (LRTD), and other respiratory viruses was calculated by season, region, age group, and RSV subtype. HRQoL was assessed via patient-reported outcomes. RESULTS: The study included 923 ARI episodes (cRSV-ARI: N = 24; non-cRSV-ARI: N = 899). In years 1 and 2 (August 2021-July 2022 and August 2022-February 2023), the prevalence of cRSV-ARI was 2.5% and 2.8%, respectively. There was a predominance of RSV-B and RSV-A subtypes in years 1 and 2, respectively. In years 1 and 2 combined, 37.5% of cRSV-ARI cases had lower respiratory tract infection; all cRSV-LRTD cases occurred in those aged 60-74 years. RSV-ARI cases reported throat, chest, and respiratory symptoms, leading to impaired functioning and HRQoL. CONCLUSIONS: During the observed study period, RSV was circulating among older adults in Japan. RSV was a leading cause of ARI and LRTD. More data are needed to fully clarify the burden of RSV among older adults in Japan.


Subject(s)
Outpatients , Quality of Life , Respiratory Syncytial Virus Infections , Respiratory Tract Infections , Humans , Respiratory Syncytial Virus Infections/epidemiology , Aged , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/virology , Japan/epidemiology , Acute Disease , Middle Aged , Female , Male , Prevalence , Outpatients/statistics & numerical data , Aged, 80 and over , Cost of Illness , Hospitalization/statistics & numerical data , Respiratory Syncytial Virus, Human/isolation & purification
2.
N Engl J Med ; 388(16): 1465-1477, 2023 Apr 20.
Article in English | MEDLINE | ID: mdl-37018468

ABSTRACT

BACKGROUND: Respiratory syncytial virus (RSV) infection causes considerable illness in older adults. The efficacy and safety of an investigational bivalent RSV prefusion F protein-based (RSVpreF) vaccine in this population are unknown. METHODS: In this ongoing, phase 3 trial, we randomly assigned, in a 1:1 ratio, adults (≥60 years of age) to receive a single intramuscular injection of RSVpreF vaccine at a dose of 120 µg (RSV subgroups A and B, 60 µg each) or placebo. The two primary end points were vaccine efficacy against seasonal RSV-associated lower respiratory tract illness with at least two or at least three signs or symptoms. The secondary end point was vaccine efficacy against RSV-associated acute respiratory illness. RESULTS: At the interim analysis (data-cutoff date, July 14, 2022), 34,284 participants had received RSVpreF vaccine (17,215 participants) or placebo (17,069 participants). RSV-associated lower respiratory tract illness with at least two signs or symptoms occurred in 11 participants in the vaccine group (1.19 cases per 1000 person-years of observation) and 33 participants in the placebo group (3.58 cases per 1000 person-years of observation) (vaccine efficacy, 66.7%; 96.66% confidence interval [CI], 28.8 to 85.8); 2 cases (0.22 cases per 1000 person-years of observation) and 14 cases (1.52 cases per 1000 person-years of observation), respectively, occurred with at least three signs or symptoms (vaccine efficacy, 85.7%; 96.66% CI, 32.0 to 98.7). RSV-associated acute respiratory illness occurred in 22 participants in the vaccine group (2.38 cases per 1000 person-years of observation) and 58 participants in the placebo group (6.30 cases per 1000 person-years of observation) (vaccine efficacy, 62.1%; 95% CI, 37.1 to 77.9). The incidence of local reactions was higher with vaccine (12%) than with placebo (7%); the incidences of systemic events were similar (27% and 26%, respectively). Similar rates of adverse events through 1 month after injection were reported (vaccine, 9.0%; placebo, 8.5%), with 1.4% and 1.0%, respectively, considered by the investigators to be injection-related. Severe or life-threatening adverse events were reported in 0.5% of vaccine recipients and 0.4% of placebo recipients. Serious adverse events were reported in 2.3% of participants in each group through the data-cutoff date. CONCLUSIONS: RSVpreF vaccine prevented RSV-associated lower respiratory tract illness and RSV-associated acute respiratory illness in adults (≥60 years of age), without evident safety concerns. (Funded by Pfizer; RENOIR ClinicalTrials.gov number, NCT05035212; EudraCT number, 2021-003693-31.).


Subject(s)
Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus Vaccines , Respiratory Tract Infections , Aged , Humans , Antibodies, Viral , Double-Blind Method , Respiratory Syncytial Virus Infections/diagnosis , Respiratory Syncytial Virus Infections/epidemiology , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus Vaccines/administration & dosage , Respiratory Syncytial Virus Vaccines/adverse effects , Respiratory Syncytial Virus Vaccines/therapeutic use , Vaccines, Combined/administration & dosage , Vaccines, Combined/adverse effects , Vaccines, Combined/therapeutic use , Vaccine Efficacy , Treatment Outcome , Middle Aged , Injections, Intramuscular , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/prevention & control
3.
J Asthma ; 60(3): 616-624, 2023 03.
Article in English | MEDLINE | ID: mdl-35707873

ABSTRACT

OBJECTIVE: To assess the long-term safety of tezepelumab in Japanese patients with severe uncontrolled asthma. METHODS: This phase III, 52-week, open-label, single-arm study (NOZOMI, NCT04048343) evaluated the safety/tolerability of subcutaneous (SC) tezepelumab 210 mg every 4 weeks (Q4W) in Japanese patients aged 12-80 years with severe uncontrolled asthma using medium- to high-dose inhaled corticosteroids and at least one additional asthma controller medication, with/without oral corticosteroids. Exploratory outcomes included efficacy (asthma exacerbations, lung function, and asthma control), pharmacokinetic parameters, and immunogenicity. RESULTS: Among 65 patients (median age 52 years), 39 (60%) experienced 94 adverse events (AEs; predominantly nasopharyngitis [13/65]) of mild (49.2%), moderate (7.7%), or severe (3.1%) intensity. Two patients had transient injection site erythema related to tezepelumab. Four patients reported serious AEs unrelated to tezepelumab and one AE led to treatment discontinuation. AEs of special interest were infrequent and generally mild/moderate. Apart from a decrease in blood eosinophils (an expected pharmacodynamic effect), no notable trends/clinically relevant changes in hematology, clinical chemistry, or urinalysis parameters were observed. Among exploratory outcomes, tezepelumab was associated with a low annualized asthma exacerbation rate over the study period (0.11/patient-year), improved lung function (mean [standard deviation] change from baseline of 0.075 [0.226] L in pre-dose/pre-bronchodilator forced expiratory volume in 1 s), and better asthma control versus baseline (responder rate: 71.4% at Week 52). CONCLUSION: Tezepelumab 210 mg SC Q4W in Japanese patients with severe uncontrolled asthma showed safety/tolerability profiles similar to international data, with low exacerbation rates and improvements in lung function and asthma control.


Subject(s)
Anti-Asthmatic Agents , Antibodies, Monoclonal, Humanized , Asthma , Humans , Middle Aged , Adrenal Cortex Hormones/therapeutic use , Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Double-Blind Method , East Asian People , Antibodies, Monoclonal, Humanized/therapeutic use
4.
Allergol Int ; 72(1): 82-88, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35977863

ABSTRACT

BACKGROUND: Tezepelumab, a human monoclonal antibody, blocks the activity of thymic stromal lymphopoietin. In the phase 3 NAVIGATOR study (NCT03347279), tezepelumab reduced exacerbations by 56% compared with placebo in adults and adolescents with severe, uncontrolled asthma. This analysis evaluated the efficacy and safety of tezepelumab in NAVIGATOR patients recruited in Japan. METHODS: NAVIGATOR was a phase 3, multicenter, randomized, double-blind, placebo-controlled study. Patients (12-80 years old) were randomized 1:1 to receive tezepelumab 210 mg or placebo subcutaneously every 4 weeks for 52 weeks. Endpoints assessed included: the annualized asthma exacerbation rate (AAER) over 52 weeks (primary endpoint) and the change from baseline to week 52 in pre-bronchodilator forced expiratory volume in 1 s (FEV1) and Asthma Control Questionnaire (ACQ)-6 score. The safety of tezepelumab was also assessed. RESULTS: Overall, 97 patients recruited in Japan were randomized (tezepelumab, n = 58; placebo, n = 39). The AAER over 52 weeks was 1.54 (95% confidence interval [CI]: 0.90, 2.64) with tezepelumab compared with 3.12 (95% CI: 1.82, 5.35) with placebo (rate ratio: 0.49 [95% CI: 0.25, 0.99]; 51% reduction). For tezepelumab and placebo, the least-squares mean (standard error) change from baseline to week 52 for pre-bronchodilator FEV1 was 0.23 (0.06) L and 0.19 (0.07) L and the ACQ-6 score was -1.12 (0.15) and -0.97 (0.19), respectively. The frequency of adverse events was similar between treatment groups (tezepelumab, 86.2%; placebo, 87.2%). CONCLUSIONS: Tezepelumab reduced exacerbations compared with placebo, and was well tolerated, in NAVIGATOR patients with severe, uncontrolled asthma recruited in Japan.


Subject(s)
Anti-Asthmatic Agents , Asthma , Adult , Adolescent , Humans , Child , Young Adult , Middle Aged , Aged , Aged, 80 and over , Anti-Asthmatic Agents/adverse effects , Bronchodilator Agents/therapeutic use , Japan , Double-Blind Method , Treatment Outcome
5.
Lancet Diabetes Endocrinol ; 9(9): 563-574, 2021 09.
Article in English | MEDLINE | ID: mdl-34293304

ABSTRACT

BACKGROUND: Semaglutide is an effective treatment for type 2 diabetes; however, 20-30% of patients given semaglutide 1·0 mg do not reach glycaemic treatment goals. We aimed to investigate the efficacy and safety of once-weekly semaglutide 2·0 mg versus 1·0 mg in adults with inadequately controlled type 2 diabetes on a stable dose of metformin with or without a sulfonylurea. METHODS: We did a 40-week, randomised, active-controlled, parallel-group, double-blind, phase 3B trial (SUSTAIN FORTE) at 125 outpatient clinics in ten countries. Participants (≥18 years) with inadequately controlled type 2 diabetes (HbA1c 8·0-10·0%) with metformin and with or without sulfonylurea were randomly assigned (1:1) by an interactive web-response system to 2·0 mg or 1·0 mg once-weekly semaglutide. Participants, site personnel, the clinical study group, and investigators were masked to the randomised treatment. Outcomes included change from baseline at week 40 in HbA1c (primary outcome) and bodyweight (secondary confirmatory outcome), evaluated through trial product estimand (no treatment discontinuation or without rescue medication) and treatment policy estimand (regardless of treatment discontinuation or rescue medication) strategies. This study is registered with ClinicalTrials.gov, NCT03989232; EudraCT, 2018-004529-96; and WHO, U1111-1224-5162. FINDINGS: Between June 19 and Nov 28, 2019, of 1515 adults assessed for eligibility, 961 participants (mean age 58·0 years [SD 10·0]; 398 [41%] women) were included. Participants were randomly assigned to once-weekly semaglutide 2·0 mg (n=480 [50%]) or 1·0 mg (n=481 [50%]); 462 (96%) patients in the semaglutide 2·0 mg group and 471 (98%) in the semaglutide 1·0 mg group completed the trial. Mean baseline HbA1c was 8·9% (SD 0·6; 73·3 mmol/mol [SD 6·9]) and BMI was 34·6 kg/m2 (SD 7·0). Mean change in HbA1c from baseline at week 40 was -2·2 percentage points with semaglutide 2·0 mg and -1·9 percentage points with semaglutide 1·0 mg (estimated treatment difference [ETD] -0·23 percentage points [95% CI -0·36 to -0·11]; p=0·0003; trial product estimand) and -2·1 percentage points with semaglutide 2·0 mg and -1·9 percentage points with semaglutide 1·0 mg (ETD -0·18 percentage points [-0·31 to -0·04]; p=0·0098; treatment policy estimand). Mean change in bodyweight from baseline at week 40 was -6·9 kg with semaglutide 2·0 mg and -6·0 kg with semaglutide 1·0 mg (ETD -0·93 kg [95% CI -1·68 to -0·18]; p=0·015; trial product estimand) and -6·4 kg with semaglutide 2·0 mg and -5·6 kg with semaglutide 1·0 mg (ETD -0·77 kg [-1·55 to 0·01]; p=0·054; treatment policy estimand). Gastrointestinal disorders were the most commonly reported adverse events (163 [34%] in the 2·0 mg group and 148 [31%] in the 1·0 mg group). Serious adverse events were similar between treatment groups, reported for 21 (4%) participants given semaglutide 2·0 mg and 25 (5%) participants given semaglutide 1·0 mg. Three deaths were reported during the trial (one in the semaglutide 1·0 mg group and two in the semaglutide 2·0 mg group). INTERPRETATION: Semaglutide 2·0 mg was superior to 1·0 mg in reducing HbA1c, with additional bodyweight loss and a similar safety profile. This higher dose provides a treatment intensification option for patients with type 2 diabetes treated with semaglutide in need of additional glycaemic control. FUNDING: Novo Nordisk.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Glucagon-Like Peptides/administration & dosage , Hypoglycemic Agents/administration & dosage , Double-Blind Method , Drug Therapy, Combination , Female , Humans , Male , Metformin/administration & dosage , Middle Aged , Sulfonylurea Compounds/administration & dosage , Treatment Outcome
6.
J Med Internet Res ; 21(4): e13520, 2019 04 26.
Article in English | MEDLINE | ID: mdl-30982776

ABSTRACT

BACKGROUND: Tobacco is a major public health concern. A 12-week standard smoking cessation program is available in Japan; however, it requires face-to-face clinic visits, which has been one of the key obstacles to completing the program, leading to a low smoking cessation success rate. Telemedicine using internet-based video counseling instead of regular clinic visits could address this obstacle. OBJECTIVE: This study aimed to evaluate the efficacy and feasibility of an internet-based remote smoking cessation support program compared with the standard face-to-face clinical visit program among patients with nicotine dependence. METHODS: This study was a randomized, controlled, open-label, multicenter, noninferiority trial. We recruited nicotine-dependent adults from March to June 2018. Participants randomized to the telemedicine arm received internet-based video counseling, whereas control participants received standard face-to-face clinic visits at each time point in the smoking cessation program. Both arms received a CureApp Smoking Cessation smartphone app with a mobile exhaled carbon monoxide checker. The primary outcome was a continuous abstinence rate (CAR) from weeks 9 to 12. Full analysis set was used for data analysis. RESULTS: We randomized 115 participants with nicotine dependence: 58 were allocated to the telemedicine (internet-based video counseling) arm and 57, to the control (standard face-to-face clinical visit) arm. We analyzed all 115 participants for the primary outcome. Both telemedicine and control groups had similar CARs from weeks 9 to 12 (81.0% vs 78.9%; absolute difference, 2.1%; 95% CI -12.8 to 17.0), and the lower limit of the difference between groups (-12.8%) was greater than the prespecified limit (-15%). CONCLUSIONS: The application of telemedicine using internet-based video counseling as a smoking cessation program had a similar CAR from weeks 9 to 12 as that of the standard face-to-face clinical visit program. The efficacy of the telemedicine-based smoking cessation program was not inferior to that of the standard visit-based smoking cessation program. TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trials Registry: UMIN000031620; https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000035975.


Subject(s)
Ambulatory Care/methods , Smoking Cessation/psychology , Telemedicine/methods , Treatment Outcome , Female , Humans , Male , Middle Aged , Research Design
7.
Int J Chron Obstruct Pulmon Dis ; 14: 2979-2991, 2019.
Article in English | MEDLINE | ID: mdl-31920295

ABSTRACT

Background: KRONOS, a Phase III, multicenter, randomized, double-blind study (NCT02497001) conducted in Canada, China, Japan, and the USA, assessed the efficacy and safety of budesonide/glycopyrrolate/formoterol fumarate metered dose inhaler (BGF MDI), a triple fixed-dose combination therapy, relative to dual therapies in patients with moderate-to-very severe COPD. Here we present findings from the Japanese subgroup of KRONOS. Methods: Patients received BGF MDI 320/18/9.6µg, glycopyrrolate/formoterol fumarate (GFF) MDI 18/9.6µg, budesonide/formoterol fumarate (BFF) MDI 320/9.6µg, or budesonide/formoterol fumarate dry powder inhaler (BUD/FORM DPI) 400/12µg twice-daily for 24 weeks. The primary endpoint was the change from baseline in morning pre-dose trough forced expiratory volume in 1 s (FEV1) over Weeks 12-24. Symptoms, quality of life, exacerbations, and safety were also assessed. Results: In total, 416 Japanese patients (21.9% of the global KRONOS population) were randomized and treated with BGF MDI (n=139), GFF MDI (n=138), BFF MDI (n=70), or BUD/FORM DPI (n=69). Nominally significant improvements in the change from baseline in morning pre-dose trough FEV1 over Weeks 12-24 were observed for BGF MDI vs GFF MDI (least squares mean [LSM] difference 37 mL, 95% confidence interval [CI] 3, 72; P=0.0337) and BFF MDI (67 mL; 95% CI 25, 109; P=0.0020). Treatment with BGF MDI led to a nominally significant reduction in the rate of moderate/severe exacerbations vs GFF MDI (rate ratio 0.40, 95% CI 0.19, 0.83; P=0.0142). Compared with dual therapies, numerical improvements were observed with BGF MDI for Transition Dyspnea Index focal score and the change from baseline in Evaluating Respiratory Symptoms in COPD total score (P≤0.3899). All treatments were generally well tolerated. Conclusion: BGF MDI nominally significantly improved lung function and numerically improved symptoms vs GFF MDI and BFF MDI. BGF MDI nominally significantly reduced exacerbations vs GFF MDI in Japanese patients with COPD. Efficacy and safety findings were generally comparable to those in the global KRONOS population.


Subject(s)
Budesonide/administration & dosage , Formoterol Fumarate/administration & dosage , Glycopyrrolate/administration & dosage , Metered Dose Inhalers , Pulmonary Disease, Chronic Obstructive , Bronchodilator Agents/administration & dosage , Double-Blind Method , Drug Combinations , Drug Monitoring/methods , Female , Humans , Japan , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/drug therapy , Pulmonary Disease, Chronic Obstructive/physiopathology , Respiratory Function Tests/methods , Severity of Illness Index , Treatment Outcome
8.
Int J Chron Obstruct Pulmon Dis ; 14: 2993-3002, 2019.
Article in English | MEDLINE | ID: mdl-31920296

ABSTRACT

Background: Budesonide/glycopyrrolate/formoterol fumarate metered dose inhaler (BGF MDI) is a triple fixed-dose combination for COPD. The long-term safety of triple therapy for COPD has not been investigated in Japanese patients. In this 28-week extension study (NCT03262012), we investigated the long-term safety and tolerability of BGF MDI in Japanese patients with moderate-to-very severe COPD who completed the 24-week Phase III randomized, double-blind, multicenter KRONOS study (NCT02497001). Materials and methods: Patients randomized to BGF MDI 320/18/9.6 µg, glycopyrrolate/formoterol fumarate (GFF) MDI 18/9.6 µg, budesonide/formoterol fumarate (BFF) MDI 320/9.6 µg, or budesonide/formoterol fumarate dry powder inhaler (BUD/FORM DPI) 400/12 µg twice-daily in KRONOS continued treatment for up to 28 additional weeks. Safety was evaluated over 52 weeks via adverse event (AE) monitoring, electrocardiograms, clinical laboratory testing, and vital sign measurements. Results: The safety population included 416 patients who received BGF MDI (n=139), GFF MDI (n=138), BFF MDI (n=70), or BUD/FORM DPI (n=69). Treatment-emergent AE (TEAE) rates were similar across treatment groups (range: 82.6-82.9%). The most frequent TEAEs overall were nasopharyngitis (32.2%) and bronchitis (9.9%). The incidence of major adverse cardiovascular events was low across groups (range: 0.0-2.9%). Over 52 weeks, the incidence of confirmed pneumonia was 9.4% (BGF MDI), 3.6% (GFF MDI), 5.7% (BFF MDI), and 2.9% (BUD/FORM DPI); in the 28-week extension period, rates were comparable across groups (range: 2.9-5.7%). Six deaths were reported (0.7-2.2% per group); none were considered treatment-related. No clinically meaningful trends were observed in electrocardiograms, laboratory parameters, or vital signs over time in any of the treatment groups. Conclusion: All treatments were well tolerated over 52 weeks, and the safety profile of BGF MDI was generally comparable to dual long-acting muscarinic antagonist (LAMA)/long-acting ß2-agonist (LABA) and inhaled corticosteroid (ICS)/LABA therapies. These findings support the long-term tolerability of BGF MDI in Japanese patients with COPD.


Subject(s)
Budesonide/administration & dosage , Formoterol Fumarate/administration & dosage , Glycopyrrolate/administration & dosage , Metered Dose Inhalers , Pulmonary Disease, Chronic Obstructive , Bronchodilator Agents/administration & dosage , Double-Blind Method , Drug Combinations , Drug Monitoring/methods , Drug Tolerance , Female , Humans , Japan , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/drug therapy , Pulmonary Disease, Chronic Obstructive/physiopathology , Respiratory Function Tests/methods , Severity of Illness Index , Time , Treatment Outcome
9.
Int J Chron Obstruct Pulmon Dis ; 13: 1187-1194, 2018.
Article in English | MEDLINE | ID: mdl-29695902

ABSTRACT

PURPOSE: Due to the burden of COPD in Japan, new pharmacologic treatments are needed to meet patient requirements. This study assessed the efficacy and safety of glycopyrronium (GP) delivered via metered dose inhaler (MDI) in Japanese patients with moderate-to-severe COPD. METHODS: This Phase IIb, multicenter, randomized, double-blind, 7-day, crossover study compared GP MDI 28.8, 14.4, and 7.2 µg with placebo MDI (all administered as two inhalations, twice daily). The primary endpoint was change from baseline in morning pre-dose trough forced expiratory volume in 1 second (FEV1) on Day 8. Secondary endpoints included FEV1 area under the curve from 0 to 2 hours (AUC0-2) and peak change from baseline in FEV1 on Days 1 and 8 and forced vital capacity AUC0-2 on Day 8. Safety was also assessed. ClinicalTrials.gov Identifier: NCT03256552; http://www.ClinicalTrials.gov. RESULTS: Sixty-six patients were randomized and 62 were included in the modified intent-to-treat population (mean age 67.5 years). All three GP MDI doses significantly improved change from baseline in morning pre-dose trough FEV1 on Day 8 compared with placebo MDI (least squares mean differences 108-131 mL; all p<0.0001). Significant improvements in secondary efficacy endpoints were also observed for all three GP MDI doses compared with placebo MDI (all p<0.0001). Dose-response plateaued at GP MDI 14.4 µg. No significant safety findings were observed with any GP MDI dose or placebo MDI. CONCLUSIONS: The results of this study suggest that GP MDI 14.4 µg (7.2 µg per inhalation) is the most appropriate dose for use in Phase III studies in Japanese patients with moderate-to-severe COPD.


Subject(s)
Bronchodilator Agents/administration & dosage , Drug Delivery Systems/instrumentation , Glycopyrrolate/administration & dosage , Lung/drug effects , Metered Dose Inhalers , Muscarinic Antagonists/administration & dosage , Pulmonary Disease, Chronic Obstructive/drug therapy , Administration, Inhalation , Adult , Aged , Aged, 80 and over , Bronchodilator Agents/adverse effects , Cross-Over Studies , Double-Blind Method , Female , Forced Expiratory Volume , Glycopyrrolate/adverse effects , Humans , Intention to Treat Analysis , Japan , Lung/physiopathology , Male , Middle Aged , Muscarinic Antagonists/adverse effects , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/physiopathology , Severity of Illness Index , Time Factors , Treatment Outcome
10.
J Gastroenterol ; 53(7): 834-844, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29188387

ABSTRACT

BACKGROUND: Rabeprazole at 10 or 20 mg twice daily (b.i.d.) has been reported to be highly effective in the treatment of proton pump inhibitor (PPI)-resistant reflux esophagitis (RE) that is refractory to the standard once-daily PPI regimen. We evaluated the efficacy and safety of rabeprazole maintenance therapy at 10 mg once daily (q.d.) or b.i.d. for longer than 8 weeks. METHODS: Patients with RE refractory to standard PPI regimens for at least 8 weeks were enrolled. They were treated with rabeprazole at 10 or 20 mg b.i.d. for 8 weeks during the open-label treatment period. After endoscopic examination, those with confirmed healing entered the subsequent double-blind maintenance therapy. During this period, the subjects were randomized to receive rabeprazole 10 mg q.d. (control) or 10 mg b.i.d. The primary endpoint was the endoscopic no-recurrence rate at Week 52. RESULTS: In total, 517 subjects entered the treatment, and 359 subjects continued on maintenance therapy. The full analysis set for central assessment included 343 subjects. The no-recurrence rate at Week 52 was significantly higher in the b.i.d. group (73.9%; p < 0.001, χ2 test) than in the q.d. group (44.8%). In particular, the b.i.d. regimen was more effective in all subgroups with Los Angeles Classification Grade B to D at treatment entry. CONCLUSIONS: In the maintenance treatment of PPI-resistant RE, rabeprazole at 10 mg b.i.d. exerted a stronger recurrence-preventing effect than 10 mg q.d. over 52 weeks. No particular safety issues were noted during long-term administration. ClinicalTrials.gov number: NCT02135107.


Subject(s)
Anti-Ulcer Agents/administration & dosage , Anti-Ulcer Agents/adverse effects , Esophagitis, Peptic/drug therapy , Gastroesophageal Reflux/drug therapy , Proton Pump Inhibitors/administration & dosage , Proton Pump Inhibitors/adverse effects , Rabeprazole/administration & dosage , Rabeprazole/adverse effects , Aged , Double-Blind Method , Drug Administration Schedule , Drug Resistance , Endoscopy , Esophagitis, Peptic/diagnostic imaging , Female , Gastrins/blood , Gastroesophageal Reflux/diagnostic imaging , Humans , Japan , Kaplan-Meier Estimate , Male , Middle Aged , Polyps , Recurrence , Secondary Prevention , Treatment Outcome
11.
J Gastroenterol Hepatol ; 31(2): 334-41, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26252950

ABSTRACT

BACKGROUND AND AIM: We recently conducted a randomized placebo-controlled trial on the efficacy and safety of rikkunshito, a standardized Japanese herbal medicine, for the treatment of functional dyspepsia (FD). The present post-hoc study aimed to evaluate the differences in clinical characteristics between responders and non-responders among FD patients who received rikkunshito for 8 weeks. METHODS: Rikkunshito responders were defined by using a global patient assessment. Candidate predictors included age, gender, smoking, alcohol consumption, body mass index, comorbidity, Helicobacter pylori infection, plasma levels of acyl ghrelin and des-acyl ghrelin, severity of dyspeptic symptoms, FD subgroup, previous medication, and the type of recruiting institution (clinic or hospital). We calculated hazard ratios (HRs) by using Cox regression analysis with the factors that were indicated to be associated with responders. RESULTS: We assigned 83 and 42 patients to responder and non-responder categories, respectively. Lack of alcohol consumption (HR, 2.04; 95% confidence interval, 1.08-3.88) and low plasma des-acyl ghrelin levels (< 177 fmol/mL; HR, 2.42; 95% confidence interval, 1.24-4.73) were significantly associated with the efficacy of rikkunshito. Lack of alcohol consumption was associated with the efficacy of rikkunshito especially among H. pylori-infected participants. On the other hand, the low plasma des-acyl ghrelin was associated with the efficacy of rikkunshito especially among H. pylori-negative participants. CONCLUSIONS: A low baseline level of plasma des-acyl ghrelin was associated with an increased treatment efficacy of rikkunshito against FD. Lack of alcohol consumption was also clinically useful for predicting the response to rikkunshito.


Subject(s)
Drugs, Chinese Herbal/therapeutic use , Dyspepsia/diagnosis , Dyspepsia/drug therapy , Ghrelin/blood , Outcome and Process Assessment, Health Care , Phytotherapy , Adult , Aged , Alcohol Drinking/adverse effects , Biomarkers/blood , Double-Blind Method , Drugs, Chinese Herbal/administration & dosage , Female , Helicobacter Infections , Helicobacter pylori , Humans , Male , Middle Aged , Multicenter Studies as Topic , Randomized Controlled Trials as Topic , Severity of Illness Index , Treatment Outcome
12.
J Gastroenterol Hepatol ; 29 Suppl 4: 53-9, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25521734

ABSTRACT

BACKGROUND AND AIM: Basolateral water channel, aquaporin-4 (AQP4), is known to be expressed in gastric parietal cells, especially in the basal side of gastric mucosa. However, the role of AQP4 in the stomach is still unknown. Histamine type 2 receptor (H2R) knockout mice, which are characterized by suppressed gastric acid secretion, are known as formation of mucosal hyperplasia with cystic dilatation and spasmolytic polypeptide-expressing metaplasia (SPEM) in the stomach. The aim of the present study is to investigate whether the expression of AQP4 is changed by the condition of acid suppression and Helicobacter pylori infection. METHODS: Male H2 R knockout mice and their controls (C57BL/6) were used. H. pylori was orally infected at the age of 5 weeks. The distributions of AQP4 and H+/K+-ATPase in the gastric mucosa were investigated by fluorescent immunohistochemistry. The mRNA expressions of AQP4, H+/K+-ATPase, sonic hedgehog (Shh), and trefoil factor-2 (TFF2) were investigated by quantitative reverse transcription polymerase chain reaction (RT-PCR). RESULTS: In the H2 R knockout mice, the distribution of AQP4-positive parietal cells was extended toward the surface of the fundic glands. Although the mRNA expression levels of AQP4 and H+/K+ATPase were elevated in H2 R knockout mice at the age of 20 weeks, the elevations were not maintained by aging or H. pylori infection. In H2 R knockout mice with H. pylori infection, the expression level of TFF2 mRNA was elevated while the ratio between AQP4 and H+/K+ ATPase mRNA expression was decreased compared with the H2 R knockout mice without H. pylori infection. CONCLUSIONS: In the H2 R knockout mice, massive SPEM was induced by H. pylori colonization and the ratio between AQP4 and H+/K+ATPase mRNA expression was decreased.


Subject(s)
Aquaporin 4/genetics , Aquaporin 4/metabolism , Gastric Mucosa/metabolism , Gastric Mucosa/pathology , Gastritis/genetics , Gastritis/microbiology , Gene Expression , Gene Knockout Techniques , Helicobacter Infections , Helicobacter pylori , Receptors, Histamine/genetics , Animals , Gastric Acid/metabolism , Gastritis/metabolism , H(+)-K(+)-Exchanging ATPase/genetics , H(+)-K(+)-Exchanging ATPase/metabolism , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , Hyperplasia , Intercellular Signaling Peptides and Proteins , Male , Metaplasia , Mice, Inbred C57BL , Mice, Knockout , Mucins/genetics , Mucins/metabolism , Muscle Proteins/genetics , Muscle Proteins/metabolism , Peptides/genetics , Peptides/metabolism , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Trefoil Factor-2
13.
Clin Sci (Lond) ; 127(7): 435-48, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24655024

ABSTRACT

Histamine H2 receptor (H2R) blockade has been reported to be beneficial for patients with chronic heart failure (CHF), but the mechanisms involved are not entirely clear. In the present study, we assessed the influences of H2R disruption on left ventricular (LV) dysfunction and the mechanisms involved in mitochondrial dysfunction and calcineurin-mediated myocardial fibrosis. H2R-knockout mice and their wild-type littermates were subjected to transverse aortic constriction (TAC) or sham surgery. The influences of H2R activation or inactivation on mitochondrial function, apoptosis and fibrosis were evaluated in cultured neonatal rat cardiomyocytes and fibroblasts as well as in murine hearts. After 4 weeks, H2R-knockout mice had higher echocardiographic LV fractional shortening, a larger contractility index, a significantly lower LV end-diastolic pressure, and more importantly, markedly lower pulmonary congestion compared with the wild-type mice. Similar results were obtained in wild-type TAC mice treated with H2R blocker famotidine. Histological examinations showed a lower degree of cardiac fibrosis and apoptosis in H2R-knockout mice. H2R activation increased mitochondrial permeability and induced cell apoptosis in cultured cardiomyocytes, and also enhanced the protein expression of calcineurin, nuclear factor of activated T-cell and fibronectin in fibroblasts rather than in cardiomyocytes. These findings indicate that a lack of H2R generates resistance towards heart failure and the process is associated with the inhibition of cardiac fibrosis and apoptosis, adding to the rationale for using H2R blockers to treat patients with CHF.


Subject(s)
Apoptosis/genetics , Heart Failure/pathology , Myocardium/pathology , Receptors, Histamine H2/physiology , Animals , Calcineurin/metabolism , Disease Progression , Fibrosis/genetics , Gene Knockout Techniques , Heart Failure/genetics , Heart Failure/metabolism , Hemodynamics , Mice , Mice, Knockout , Mitochondria/metabolism , Models, Biological , Permeability , Receptors, Histamine H2/genetics , Receptors, Histamine H2/metabolism
14.
Gut ; 63(7): 1061-8, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24326741

ABSTRACT

OBJECTIVES: To evaluate if esomeprazole prevents recurrent peptic ulcer in adult patients with a history of peptic ulcer receiving low-dose acetylsalicylic acid (ASA, aspirin) for cardiovascular protection in East Asia. METHODS: In this prospective, randomised, double-blind, placebo-controlled trial conducted in Japan, Korea and Taiwan, eligible patients receiving low-dose ASA for cardiovascular protection (81-324 mg/day) were randomised to esomeprazole 20 mg/day or placebo for ≤72 weeks. All patients received concomitant mucosal protection (gefarnate 100 mg/day). The primary endpoint was time to ulcer recurrence (Kaplan-Meier analysis). Efficacy findings are presented up to week 48, as per a planned interim analysis within the study protocol. RESULTS: A total of 364 patients (79.9% men; mean age, 67.1 years) comprised the full analysis set (esomeprazole, n=182; placebo, n=182). There was a statistically significant difference in the time to ulcer recurrence between esomeprazole and placebo (HR 0.09; 96.65% CI 0.02 to 0.41; p<0.001). The estimated ulcer-free rate at week 12 was 99.3% (esomeprazole) and 89.0% (placebo). The high estimated ulcer-free rate for esomeprazole was maintained through to week 48 (98.3% vs. 81.2% of placebo-treated patients). No factors, other than female gender, reduced time to ulcer recurrence in addition to the effect of esomeprazole (p<0.001). Treatment with esomeprazole was generally well tolerated. CONCLUSIONS: Daily esomeprazole 20 mg is efficacious and well tolerated in reducing the recurrence of peptic ulcer in East-Asian patients with a history of ulcers who are taking low-dose ASA for cardiovascular protection. CLINICALTRIALGOV IDENTIFIER: NCT01069939.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Anti-Ulcer Agents/therapeutic use , Aspirin/adverse effects , Esomeprazole/therapeutic use , Peptic Ulcer/prevention & control , Adult , Aged , Asian People , Double-Blind Method , Drug Administration Schedule , Female , Humans , Japan , Kaplan-Meier Estimate , Male , Middle Aged , Peptic Ulcer/chemically induced , Peptic Ulcer/ethnology , Prospective Studies , Republic of Korea , Secondary Prevention , Taiwan , Treatment Outcome
15.
Basic Res Cardiol ; 108(3): 342, 2013 May.
Article in English | MEDLINE | ID: mdl-23467745

ABSTRACT

There is evidence that H2R blockade improves ischemia/reperfusion (I/R) injury, but the underlying cellular mechanisms remain unclear. Histamine is known to increase vascular permeability and induce apoptosis, and these effects are closely associated with endothelial and mitochondrial dysfunction, respectively. Here, we investigated whether activation of the histamine H2 receptor (H2R) exacerbates myocardial I/R injury by increasing mitochondrial and endothelial permeability. Serum histamine levels were measured in patients with coronary heart disease, while the influence of H2R activation was assessed on mitochondrial and endothelial function in cultured cardiomyocytes or vascular endothelial cells, and myocardial I/R injury in mice. The serum histamine level was more than twofold higher in patients with acute myocardial infarction than in patients with angina or healthy controls. In neonatal rat cardiomyocytes, histamine dose-dependently reduced viability and induced apoptosis. Mitochondrial permeability and the levels of p-ERK1/2, Bax, p-DAPK2, and caspase 3 were increased by H2R agonists. In cultured human umbilical vein endothelial cells (HUVECs), H2R activation increased p-ERK1/2 and p-moesin levels and also enhanced permeability of HUVEC monolayer. All of these effects were abolished by the H2R blocker famotidine or the ERK inhibitor U0126. After I/R injury or permanent ischemia, the infarct size was reduced by famotidine and increased by an H2R agonist in wild-type mice. In H2R KO mice, the infarct size was smaller; myocardial p-ERK1/2, p-DAPK2, and mitochondrial Bax were downregulated. These findings indicate that H2R activation exaggerates myocardial I/R injury by promoting myocardial mitochondrial dysfunction and by increasing cardiac vascular endothelial permeability.


Subject(s)
Histamine/metabolism , Human Umbilical Vein Endothelial Cells/metabolism , Mitochondria, Heart/metabolism , Myocardial Infarction/metabolism , Myocardial Reperfusion Injury/metabolism , Myocytes, Cardiac/metabolism , Receptors, Histamine H2/drug effects , Angina Pectoris/blood , Animals , Apoptosis , Apoptosis Regulatory Proteins/metabolism , Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Case-Control Studies , Caspase 3/metabolism , Cell Membrane Permeability , Cells, Cultured , Death-Associated Protein Kinases , Dose-Response Relationship, Drug , Extracellular Signal-Regulated MAP Kinases/antagonists & inhibitors , Extracellular Signal-Regulated MAP Kinases/metabolism , Histamine/blood , Histamine/pharmacology , Histamine Agonists/pharmacology , Histamine H2 Antagonists/pharmacology , Human Umbilical Vein Endothelial Cells/drug effects , Human Umbilical Vein Endothelial Cells/pathology , Humans , Mice , Mice, Knockout , Microfilament Proteins/metabolism , Mitochondria, Heart/drug effects , Mitochondria, Heart/pathology , Mitochondrial Membranes/metabolism , Myocardial Infarction/genetics , Myocardial Infarction/pathology , Myocardial Infarction/prevention & control , Myocardial Reperfusion Injury/genetics , Myocardial Reperfusion Injury/pathology , Myocardial Reperfusion Injury/prevention & control , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/pathology , Permeability , Phosphorylation , Protein Kinase Inhibitors/pharmacology , Receptors, Histamine H2/deficiency , Receptors, Histamine H2/genetics , Receptors, Histamine H2/metabolism , Time Factors , bcl-2-Associated X Protein/metabolism
16.
J Neurogastroenterol Motil ; 18(3): 317-23, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22837880

ABSTRACT

BACKGROUND/AIMS: Solifenacin, a muscarinic type 3 receptor antagonist, is used to treat overactive bladder in adults. The aim of this study is to examine the efficacy of solifenacin on the symptomatic relief of diarrhea predominant irritable bowel syndrome (IBS-D). METHODS: A total of 20 patients with IBS-D were enrolled. After a 2-week observation period, all participants received solifenacin for 6 weeks. Subsequently, the administration of solifenacin was discontinued and ramosetron, a serotonin 3 receptor antagonist, was administered for 4 weeks. Overall improvement, the IBS-symptom severity scale (IBS-SSS), and frequency of defecation were assessed. RESULTS: Six weeks after initiation of solifenacin treatment and 4 weeks after initiation of ramosetron treatment, overall improvement was observed in 19 out of 20 (95%) and 17 out of 20 (85%) participants, respectively. At 2 weeks after initiation of solifenacin, overall improvement was observed in 16 out of 20 participants (80%). Total IBS-SSS scores at 2 and 6 weeks after the administration of solifenacin, and at 4 weeks after administration of ramosetron, were significantly lower than those at week 0. Compared to before administration, the participants' quality of life and frequency of defecation were significantly lower in all participants at 2 and 6 weeks after the administration of solifenacin and at 4 weeks after administration of ramosetron. CONCLUSIONS: The efficacy of solifenacin in the treatment of IBS with diarrhea was not inferior to that of ramosetron. Further placebo-controlled parallel studies are needed.

17.
Hepatogastroenterology ; 56(91-92): 703-6, 2009.
Article in English | MEDLINE | ID: mdl-19621685

ABSTRACT

BACKGROUND/AIMS: Patients with erosive gastroesophageal reflux disease (GERD) have rapid recurrence after treatment withdrawal. The aim is to study the influences of CYP2C19 polymorphism on recurrence of GERD during proton pump inhibitor maintenance therapy. METHODOLOGY: Ninety-nine patients with initial healing of GERD (judged by endoscopy) after 8 wk of treatment with PPIs were enrolled into maintenance therapy for 6 mo with rabeprazole (10 mg/day), omeprazole (20 mg/day) or lansoprazole (15 mg/day). The recurrence of GERD symptoms in the maintenance therapy was assessed by a QUEST questionnaire. RESULTS: The recurrence rate of GERD symptoms in the group of CYP2C19 homozygous extensive metabolizers (38.5%) was significantly greater than those in groups of heterozygous extensive metabolizers (10.9%) and poor metabolizers (5.6%). The recurrence rates in patients treated with omeprazole (25%) and lansoprazole (30.8%) were significantly greater than that with rabeprazole (4.4%). The gender, age and H. pylori did not significantly affect the rate. CONCLUSIONS: The CYP2C19 genotypes affected the recurrence rate of GERD symptoms during PPI maintenance therapy. The reason for the low recurrence rate with 10 mg/day rabeprazole possibly is due to its sufficient acid suppression independent of CYP2C19 genotypes in Japanese patients.


Subject(s)
Aryl Hydrocarbon Hydroxylases/genetics , Esophagitis, Peptic/epidemiology , Esophagitis, Peptic/genetics , Gastroesophageal Reflux/epidemiology , Polymorphism, Genetic , Proton Pump Inhibitors/therapeutic use , Adult , Age Factors , Aged , Anti-Ulcer Agents/therapeutic use , Asian People/genetics , Cytochrome P-450 CYP2C19 , Esophagitis, Peptic/drug therapy , Female , Gastroesophageal Reflux/drug therapy , Gastroesophageal Reflux/genetics , Helicobacter pylori , Humans , Japan , Male , Middle Aged , Recurrence , Sex Factors , Treatment Outcome
18.
Dig Dis Sci ; 54(8): 1625-35, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19507031

ABSTRACT

Spasmolytic polypeptide (SP/TFF2)-expressing metaplasia (SPEM) is induced by oxyntic atrophy and is known as a precancerous or paracancerous lesion. We seek to determine whether the gastrin receptor or H(2) histamine receptor influence the development of SPEM. DMP-777 was administered to gastrin receptor and/or H(2) receptor-deficient mice and wild-type mice. Gastric mucosal lineage changes were analyzed. The mucosa from double knockout mice and H(2) receptor knockout mice contained elevated numbers of dual TFF2 and intrinsic factor immunoreactive cells even before DMP-777 treatment. All genotypes of mice showed SPEM after 7-day treatment. In all types of knockout mice, the number of TFF2 immunoreactive cells remained elevated after cessation of treatment. The H(2) receptor and gastrin receptor do not affect emergence of SPEM. However, it is suggested that the absence of H(2) receptor signaling causes a delay in the maturation of chief cells from mucous neck cells.


Subject(s)
Cell Lineage , Gastric Mucosa/cytology , Parietal Cells, Gastric/pathology , Receptor, Cholecystokinin B/metabolism , Receptors, Histamine H2/metabolism , Animals , Atrophy/chemically induced , Atrophy/pathology , Azetidines/adverse effects , Azetidines/pharmacology , Cell Differentiation/drug effects , Cell Lineage/drug effects , Cell Proliferation/drug effects , Gastric Mucosa/metabolism , Gastrins/blood , Intrinsic Factor/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Mucins/metabolism , Muscle Proteins/metabolism , Parietal Cells, Gastric/metabolism , Peptides/metabolism , Piperazines/adverse effects , Piperazines/pharmacology , Receptor, Cholecystokinin B/genetics , Receptors, Histamine H2/genetics , Trefoil Factor-2
19.
J Neurochem ; 107(1): 208-17, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18691388

ABSTRACT

Histamine H2 receptor (H2R) is a member of G protein-coupled receptor family. Agonist stimulation of H2R results in several cellular events including activation of adenylate cyclase and phospholipase C, desensitization of the receptor, activation of extracellular signal-regulated kinases ERK1/2, and receptor endocytosis. In this study, we identified a GTPase dynamin as a binding partner of H2R. Dynamin could associate with H2R both in vitro and in vivo. Functional analyses using dominant-negative form of dynamin (K44E-dynamin) revealed that cAMP production and the following H2R desensitization are independent of dynamin. However, the agonist-induced H2R internalization was inhibited by co-expression of K44E-dynamin. Furthermore, activation of extracellular-signal regulated kinases ERK1/2 in response to dimaprit, an H2R agonist, was attenuated by K44E-dynamin. Although H2R with truncation of 51 amino acids at its carboxy-terminus did not internalize after agonist stimulation, it still activated ERK1/2, but the degree of this activation was less than that of the wild-type receptor. Finally, K44E dynamin did not affect ERK1/2 activation induced by internalization-deficient H2R. These results suggest that the agonist-induced H2R internalization and ERK1/2 activation are partially dynamin-dependent. Furthermore, ERK1/2 activation via H2R is likely dependent of the endocytotic process rather than dynamin itself.


Subject(s)
Dynamins/metabolism , Endocytosis/physiology , Extracellular Signal-Regulated MAP Kinases/metabolism , Histamine Agonists/pharmacology , Receptors, Histamine H2/drug effects , Receptors, Histamine H2/metabolism , Animals , COS Cells , Chlorocebus aethiops , Cyclic AMP/biosynthesis , Dimaprit/pharmacology , Endocytosis/drug effects , Enzyme Activation/drug effects , Enzyme Activation/physiology , Extracellular Signal-Regulated MAP Kinases/drug effects , Humans , Mitogen-Activated Protein Kinase 1/drug effects , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/drug effects , Mitogen-Activated Protein Kinase 3/metabolism , Protein Structure, Tertiary/physiology , Protein Transport/drug effects , Protein Transport/physiology , Receptors, Histamine H2/chemistry , Signal Transduction/drug effects , Signal Transduction/physiology
20.
Am J Physiol Endocrinol Metab ; 294(4): E719-25, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18270303

ABSTRACT

Several serine/threonine kinases reportedly phosphorylate serine residues of IRS-1 and thereby induce insulin resistance. In this study, to investigate the effect of mTOR/raptor on insulin signaling and metabolism in K/KAy mice with genetic obesity-associated insulin resistance, a dominant negative raptor, COOH-terminally deleted raptor (raptor-DeltaC(T)), was overexpressed in the liver via injection of its adenovirus into the circulation. Hepatic raptor-DeltaC(T) expression levels were 1.5- to 4-fold that of endogenously expressed raptor. Glucose tolerance in raptor-DeltaC(T)-overexpressing mice improved significantly compared with that of LacZ-overexpressing mice. Insulin-induced activation of p70S6 kinase (p70(S6k)) was significantly suppressed in the livers of raptor-DeltaC(T) overexpressing mice. In addition, insulin-induced IRS-1, Ser(307), and Ser(636/639) phosphorylations were significantly suppressed in the raptor-DeltaC(T)-overexpressing liver, whereas tyrosine phosphorylation of IRS-1 was increased. PI 3-kinase activation in response to insulin stimulation was increased approximately twofold, and Akt phosphorylation was clearly enhanced under both basal and insulin-stimulated conditions in the livers of raptor-DeltaC(T) mice. Thus, our data indicate that suppression of the mTOR/p70(S6k) pathway leads to improved glucose tolerance in K/KAy mice. These observations may contribute to the development of novel antidiabetic agents.


Subject(s)
Glucose Intolerance/metabolism , Insulin Resistance/physiology , Insulin/metabolism , Liver/physiology , Proto-Oncogene Proteins c-akt/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Adenoviridae/genetics , Animals , Cell Line , Gene Transfer Techniques , Glucose Intolerance/physiopathology , Humans , Insulin Receptor Substrate Proteins , Kidney/cytology , Mechanistic Target of Rapamycin Complex 1 , Mice , Mice, Mutant Strains , Multiprotein Complexes , Obesity/metabolism , Obesity/physiopathology , Phosphorylation , Proteins , Ribosomal Protein S6 Kinases, 70-kDa/metabolism , TOR Serine-Threonine Kinases
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