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論文
Takeshita, Yumie ; Takamura, Toshinari ; Kita, Yuki ; Ando, Hitoshi ; Ueda, Teruyuki ; Kato, Kenichiro ; Misu, Hirofumi ; Sunagozaka, Hajime ; Sakai, Yoshio ; Yamashita, Tatsuya ; Mizukoshi, Eishiro ; Honda, Masao ; Kaneko, Shuichi
出版情報: Metabolism: Clinical and Experimental.  61  pp.1388-1394,  2012-10-01.  Elsevier
URL: http://hdl.handle.net/2297/32870
概要: Branched-chain amino acids (BCAAs) improve disorders of albumin metabolism, quality of life, subjective symptoms, and prognosis in patients with chronic hepatitis. However, it remains unclear whether they improve insulin resistance. We examined the effects of BCAAs on glucose tolerance and insulin sensitivity in patients with chronic hepatitis C and insulin resistance. Individuals with a definitive diagnosis of chronic hepatitis C and insulin resistance were eligible for participation. Eligible participants were randomly assigned to the BCAA group or a control group. Participants were then crossed over to the other treatment for a further 12 weeks. Baseline clinical features, laboratory markers, fatty acid levels, and insulin sensitivity, assessed with oral glucose tolerance tests and a hyperinsulinemic euglycemic clamp, were also examined before and 12 and 24 weeks after the beginning of the study. Of the 27 patients who completed the study, 14 began in the BCAA group and 13 began as controls. There were no significant differences in glucose metabolism parameters or lipid profiles between the groups. HbA1c values were improved in 10 patients and worsened or remained unchanged in 17 patients. The only predictive variable for change in HbA1c was the baseline Matsuda index: the lower the index, the greater the improvement in HbA1c values. BCAA therapy did not have adverse effects on glucose tolerance or insulin sensitivity in patients with chronic hepatitis C and insulin resistance. Moreover, it had a therapeutic effect on HbA1c values in patients with marked peripheral (primarily muscle) insulin resistance. © 2012 Elsevier Inc. 続きを見る
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Takeshita, Yumie ; Takamura, Toshinari ; Kita, Yuki ; Takazakura, Akiko ; Kato, Ken-ichiro ; Isobe, Yuki ; Kaneko, Shuichi
出版情報: BMJ Open Diabetes Research & Care.  3  pp.e000122-,  2015-01-01.  BMJ
URL: http://hdl.handle.net/2297/45566
概要: Purpose We determined the feasibility of substituting sitagliptin or mitiglinide for bolus insulin injection therapy in patients with type 2 diabetes. Methods 60 patients with type 2 diabetes were enrolled and randomized to switch from mealtime dosing of a rapid-acting insulin analog to either sitagliptin or mitiglinide for 16 weeks. Results Body weight, body mass index, and waist circumference decreased significantly in both groups at the end of the study. Mitiglinide significantly increased fasting plasma glucose (FPG) levels at the end of the study from 146.5±36.3 to 168.0±38.8 mg/dL, whereas sitagliptin did not affect FPG. Glycated hemoglobin (HbA1c) and 1,5-anhydroglucitol increased significantly in both groups. The C peptide immunoreactivity (CPR) responses after arginine were diminished in both groups. γ-GTP and triglycerides increased, and high-density lipoprotein cholesterol and adiponectin decreased, in the sitagliptin group, but not in the mitiglinide group. Mean Diabetes Treatment Satisfaction Questionnaire scores improved significantly in both groups. Patients whose mean total daily doses of rapid-acting insulin analog were 16.6 and 17.8 units were switched to sitagliptin and mitiglinide, respectively, without a change in the HbA1c level. Total insulin doses/body weight predicted changes in HbA1c only in the sitagliptin group, but not in the mitiglinide group. Use of >0.27 IU/kg of a rapid-acting insulin analog predicted an increase in HbA1c after switching to sitagliptin. The CPR index (CPI) was also a predictor for a change in HbA1c in the sitagliptin group, but not in the mitiglinide group; patients with a CPI<1.4 developed a worse HbA1c after switching to sitagliptin. Conclusions Sitagliptin may predominantly act on FPG, whereas mitiglinide may act on postprandial plasma glucose to achieve glycemic control after switching from a bolus insulin regimen. Additional therapy to sitagliptin or mitiglinide is clearly required to obtain equivalent glycemic control in patients using a higher dose of insulin. 続きを見る
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Takeshita, Yumie ; Takamura, Toshinari ; Kita, Yuki ; Otoda, Toshiki ; Kato, Ken-ichiro ; Wakakuri, Hitomi ; Yamada, Masayuki ; Misu, Hirofumi ; Matsushima, Yukiko ; Kaneko, Shuichi
出版情報: Journal of Diabetes Investigation.  6  pp.193-200,  2015-03-01.  Blackwell Publishing
URL: http://hdl.handle.net/2297/45567
概要: Introduction: A step-up strategy for dipeptidyl peptidase (DPP)-4 inhibitor-based regimens has not yet been established. In addition, similarities and differences between DPP-4 inhibitors and glucagon-like peptide (GLP)-1 receptor agonists remain to be elucidated in humans. We investigated the pleiotropic effects of vildagliptin vs liraglutide in patients with type 2 diabetes on sitagliptin-based regimens in an open-label, randomized, clinical trial. Materials and Methods: A total of 122 patients with type 2 diabetes that was inadequately controlled by sitagliptin-based regimens were randomly assigned to either vildagliptin (50 mg, twice daily) or liraglutide treatment (0.9 mg, once daily) for 12 weeks. The primary outcomes were glycated hemoglobin and body mass index. Results: Both vildagliptin and liraglutide significantly lowered glycated hemoglobin within 12 weeks after switching from sitagliptin, but liraglutide produced a greater reduction (-0.67 ± 0.12% vs -0.36 ± 0.53%). Liraglutide lowered body mass index, whereas vildagliptin did not affect body mass index. Vildagliptin lowered fasting C-peptide immunoreactivity, but liraglutide did not. Vildagliptin increased serum levels of adiponectin, arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid, whereas liraglutide had no effect on these levels. Quality of life, assessed using the diabetes treatment satisfaction questionnaire, was not impaired in either group. The most common adverse events were gastrointestinal symptoms, which occurred with similar frequencies in both groups. Conclusions: Vildagliptin-mediated improvements in glycemic control did not correlate with indices for insulin secretion and insulin sensitivity. Switching from sitagliptin to liraglutide is useful in managing hyperglycemia and weight. Each agent exerts unique pleiotropic effects. This trial was registered with the University Hospital Medical Information Network Clinical Trials Registry (no. 000004953). © 2014 The Authors. Journal of Diabetes Investigation published by Asian Association of the Study of Diabetes (AASD) and Wiley Publishing Asia Pty Ltd. 続きを見る
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Sakurai, Masaru ; Takamura, Toshinari ; Miura, Katsuyuki ; Kaneko, Shuichi ; Nakagawa, Hideaki
出版情報: Internal Medicine.  48  pp.1573-1574,  2009-01-01.  Japanese Society of Internal Medicine = 日本内科学会
URL: http://hdl.handle.net/2297/19772
概要: 金沢大学医薬保健研究域医学系
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Kurita, Seiichiro ; Takamura, Toshinari ; Ota, Tsuguhito ; Matsuzawa-Nagata, Naoto ; Kita, Yuki ; Uno, Masafumi ; Nabemoto, Satoko ; Ishikura, Kazuhide ; Misu, Hirofumi ; Ando, Hitoshi ; Zen, Yoh ; Nakanuma, Yasuni ; Kaneko, Shuichi
出版情報: European Journal of Pharmacology.  588  2008-07-07.  Elsevier
URL: http://hdl.handle.net/2297/10979
概要: 金沢大学大学院医学系研究科<br />金沢大学医薬保健研究域医学系<br />Insulin resistance is a major pathological condition associated with obesity and metabolic syndrome. Insulin resistance and the renin-angiotensin system are intimately linked. We evaluated the role of the renin-angiotensin system in the pathogenesis of insulin resistance-associated, non-alcoholic steatohepatitis by using the angiotensin II type 1 receptor blocker olmesartan medoxomil in a diabetic rat model. The effects of olmesartan on methionine- and choline-deficient (MCD) diet-induced steatohepatitis were investigated in obese, diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and control Long-Evans Tokushima Otsuka (LETO) rats. Components of the renin-angiotensin system were up-regulated in the livers of OLETF rats, compared with LETO rats. In OLETF, but not LETO, rats, oral administration of olmesartan for 8 weeks ameliorated insulin resistance. Moreover, olmesartan suppressed MCD diet-induced hepatic steatosis and the hepatic expression of lipogenic genes (sterol regulatory element-binding protein-1c and fatty acid synthase) in OLETF, but not LETO, rats. In both OLETF and LETO rats, olmesartan inhibited hepatic oxidative stress (4-hydroxy-2-nonenal-modified protein) and expression of NADPH oxidase. Olmesartan also inhibited hepatic fibrosis, stellate cell activation, and expression of fibrogenic genes (transforming growth factor-β, α1 [I] procollagen, plasminogen activator inhibitor-1) in both OLETF and LETO rats. In conclusion, pharmacological blockade of the angiotensin II type 1 receptor slows the development of steatohepatitis in the OLETF rat model. This angiotensin II type 1 receptor blocker may exert insulin resistance-associated effects against hepatic steatosis and inflammation as well as direct effects against the generation of reactive oxygen species and fibrogenesis. © 2008 Elsevier B.V. All rights reserved. 続きを見る
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Komura, Takuya ; Sakai, Yoshio ; Honda, Masao ; Takamura, Toshinari ; Matsushima, Kouji ; Kaneko, Shuichi
出版情報: Diabetes.  59  pp.634-643,  2010-03-01.  American Diabetes Association
URL: http://hdl.handle.net/2297/23966
概要: 金沢大学医薬保健研究域医学系<br />OBJECTIVE - Although patients with diabetes suffer from increased infections and a higher inci dence of cancer due to impaired immune function, details on diabetes-induced decrease in immunity are lacking. We assessed how immune-mediating peripheral blood mononuclear cells (PBMCs) are affected in diabetes. RESEARCH DESIGN AND METHODS - From 33 patients with type 2 diabetes and 28 healthy volunteers, we obtained PBMCs and investigated their susceptibility to apoptosis and functional alteration. RESULTS - In a subpopulation of PBMCs, monocytes derived from patients with diabetes were more susceptible to apoptosis than monocytes from healthy volunteers. Monocytes from patients with diabetes had decreased phagocytotic activity and were less responsive to Toll-like receptor (TLR) ligands, although the expression of TLRs did not differ significantly between the two groups. Furthermore, monocytes from patients with diabetes had a distinctly different gene expression profile compared with monocytes from normal volunteers as assessed with DNA microarray analysis. Specifically, quantitative real-time detection PCR measurements showed an elevated expression of the markers of endoplasmic reticulum (ER) stress in diabetic monocytes, and electron microscopic examination of monocytes revealed morphologic alterations in the ER of cells derived from patients with diabetes. Consistently, the ER stress inducer tunicamycin increased apoptosis of otherwise healthy monocytes and attenuated the proinflammatory responses to TLR ligands. CONCLUSIONS - These data suggest that monocytes comprise a substantially impaired subpopulation of PBMCs in patients with diabetes and that ER stress is involved in these pathologic changes mechanistically. This implies that the affected monocytes should be investigated further to better understand diabetic immunity. © 2010 by the American Diabetes Association. 続きを見る
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Hamaguchi, Erika ; Takamura, Toshinari ; Sakurai, Masaru ; Mizukoshi, Eishiro ; Zen, Yoh ; Takeshita, Yumie ; Kurita, Seiichiro ; Arai, Kuniaki ; Yamashita, Tatsuya ; Sasaki, Motoko ; Nakanuma, Yasuni ; Kaneko, Shuichi
出版情報: Diabetes Care.  33  pp.284-286,  2010-02-01.  American Diabetes Association
URL: http://hdl.handle.net/2297/21173
概要: 金沢大学医薬保健研究域医学系<br />OBJECTIVE - The goal of this study was to examine whether metabolic abnormalities are responsi ble for the histological changes observed in Japanese patients with nonalcoholic fatty liver disease (NAFLD) who have undergone serial liver biopsies. RESEARCH DESIGN AND METHODS - In total, 39 patients had undergone consecutive liver biopsies. Changes in their clinical data were analyzed, and biopsy specimens were scored histologically for stage. RESULTS - The median follow-up time was 2.4 years (range 1.0-8.5). Liver fibrosis had improved in 12 patients (30.7%), progressed in 11 patients (28.2%), and remained unchanged in 16 patients (41%). In a Cox proportional hazard model, decrease in A1C and use of insulin were associated with improvement of liver fibrosis independent of age, sex, and BMI. However, ΔA1C was more strongly associated with the improvement of liver fibrosis than use of insulin after adjustment for each other (χ2; 7.97 vs. 4.58, respectively). CONCLUSIONS - Tight glycemic control may prevent histological progression in Japanese patients with NAFLD. © 2010 by the American Diabetes Association. 続きを見る
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Sakurai, Masaru ; Takamura, Toshinari ; Miura, Katsuyuki ; Kaneko, Shuichi ; Nakagawa, Hideaki
出版情報: Metabolism: Clinical and Experimental.  58  pp.456-459,  2009-04-01.  Elsevier
URL: http://hdl.handle.net/2297/17359
概要: 金沢大学医薬保健研究域医学系<br />We attempted to determine sex differences in obesity-related metabolic abnormalities in a rela tively large middle-aged Japanese population. The study population consisted of 2935 men and 1622 women who were 35 to 59 years old. Metabolic abnormalities were determined using the Japanese criteria for metabolic syndrome, and we evaluated the number of metabolic abnormalities discriminated by waist circumference. In men, the mean number of metabolic abnormalities increased as the waist circumference increased. In women, although the mean number of metabolic abnormalities increased as the waist circumference increased, the mean number was less than 1 even in those with a waist circumference of at least 95 cm. According to the receiver operating characteristic curve, the cutoff levels yielding the maximal sensitivity plus specificity for predicting the prevalence of one or more obesity-related metabolic abnormalities were 80 cm in men and 73 cm in women. However, the positive predictive value was as low as 28.8% in men and 7.1% in women, which may not be suitable for a screening test, especially in women. Middle-aged Japanese women seem to be resistant to obesity-induced metabolic abnormalities, and waist circumference would not effectively predict the existence of metabolic syndrome. In setting the cutoff points in guidelines, a greater emphasis should be placed on the absolute risk of having abnormalities or diseases. © 2009 Elsevier Inc. All rights reserved. 続きを見る
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Sakurai, Sho ; Miura, K. ; Takamura, Toshinari ; Ishizaki, Masao ; Morikawa, Y. ; Nakamura, K. ; Yoshita, Katsushi ; Kido, Teruhiko ; Naruse, Yuchi ; Kaneko, Shuichi ; Nakagawa, H.
出版情報: Diabetic Medicine.  26  pp.753-759,  2009-08-01.  Blackwell Publishing
URL: http://hdl.handle.net/2297/19144
概要: 金沢大学医薬保健研究域医学系<br />金沢医科大学健康増進予防医学(公衆衛生学)<br />Aims This study investigated the relationship between waist c ircumference and the subsequent incidence of Type 2 diabetes and the association with insulin resistance and pancreatic B-cell function in relatively lean Japanese individuals. Methods The study participants were 3992 employees (2533 men and 1459 women, aged 35-55 years) of a metal-products factory in Japan. The incidence of diabetes was determined in annual medical examinations during an 8-year follow-up. We calculated age- and sex-adjusted hazard ratios (HRs) according to the sex-specific quintile of waist circumference at baseline. Differences in baseline insulin resistance [homeostatis model assessment (HOMA)-IR] and pancreatic B-cell function (HOMA-B) were compared between participants who developed diabetes and those who did not. Results During the follow-up, 218 participants developed diabetes. Age- and sex-adjusted HRs across the quintiles of waist circumference were 1.78, 1.00 (reference), 1.59, 3.11 and 3.30, respectively (P for trend, < 0.0001). The HR for the lowest quintile was significantly higher than that for the second quintile. Among participants with waist circumference of the lowest quintile, HOMA-B was lower in those who developed diabetes than in those who did not [33.1 (24.1-45.0) vs. 54.3 (37.9-74.6) median (interquartile range), P < 0.0001], but HOMA-IR did not differ between these groups. Conclusions There was a J-shaped relationship between waist circumference and subsequent risk for Type 2 diabetes in relatively lean Japanese individuals; lower pancreatic B-cell function may also increase the risk of diabetes in very lean Japanese people. © 2009 Diabetes UK. 続きを見る
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Matsuzawa-Nagata, Naoto ; Takamura, Toshinari ; Ando, Hitoshi ; Nakamura, Seiji ; Kurita, Seiichiro ; Misu, Hirofumi ; Ota, Tsuguhito ; Yokoyama, Masayoshi ; Honda, Masao ; Miyamoto, Ken-ichi ; Kaneko, Shuichi
出版情報: Metabolism: Clinical and Experimental.  57  pp.1071-1077,  2008-08-01.  Elsevier
URL: http://hdl.handle.net/2297/11570
概要: 金沢大学医薬保健研究域医学系<br />Insulin resistance is a key pathophysiological feature of metabolic syndrome. However, the ini tial events triggering the development of insulin resistance and its causal relations with dysregulation of glucose and fatty acids metabolism remain unclear. We investigated biological pathways that have the potential to induce insulin resistance in mice fed a high-fat diet (HFD). We demonstrate that the pathways for reactive oxygen species (ROS) production and oxidative stress are coordinately up-regulated in both the liver and adipose tissue of mice fed an HFD before the onset of insulin resistance through discrete mechanism. In the liver, an HFD up-regulated genes involved in sterol regulatory element binding protein 1c-related fatty acid synthesis and peroxisome proliferator-activated receptor α-related fatty acid oxidation. In the adipose tissue, however, the HFD down-regulated genes involved in fatty acid synthesis and up-regulated nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. Furthermore, increased ROS production preceded the elevation of tumor necrosis factor-α and free fatty acids in the plasma and liver. The ROS may be an initial key event triggering HFD-induced insulin resistance. © 2008 Elsevier Inc. All rights reserved. 続きを見る