1.

学位論文

学位
喜多, 裕樹 ; Kita, Yuki
出版情報: 博士論文要旨Abstract
URL: http://hdl.handle.net/2297/39434
概要: 博士論文要旨Abstract 以下に掲載:Plos ONE 7(9) pp.e43056-e43056 2012. Plos ONE. 共著者:Yuki Kita, Toshinari Takamura, Hirofumi Misu, Ts uguhito Ota, Seiichiro Kurita, Yumie Takeshita, Masafumi Uno, Naoto Matsuzawa-Nagata, Ken-ichiro Kato, Hitoshi Ando, Akio Fujimura, Koji Hayashi, Toru Kimura, Shuichi Kaneko 続きを見る
2.

学位論文

学位
喜多, 裕樹 ; Kita, Yuki
出版情報: 博士論文本文Full
URL: http://hdl.handle.net/2297/39524
概要: 博士論文本文Full 以下に掲載:Plos ONE 7(9) pp.e43056-e43056 2012. Plos ONE. 共著者:Yuki Kita, Toshinari Takamura, Hirofumi Misu, Tsuguh ito Ota, Seiichiro Kurita, Yumie Takeshita, Masafumi Uno, Naoto Matsuzawa-Nagata, Ken-ichiro Kato, Hitoshi Ando, Akio Fujimura, Koji Hayashi, Toru Kimura, Shuichi Kaneko 続きを見る
3.

論文

論文
Uno, Masafumi ; Kurita, Seiichiro ; Misu, Hirofumi ; Ando, Hitoshi ; Ota, Tsuguhito ; Matsuzawa-Nagata, Naoto ; Kita, Yuki ; Nabemoto, Satoko ; Akahori, Hiroshi ; Zen, Yoh ; Nakanuma, Yasuni ; Kaneko, Shuichi ; Takamura, Toshinari
出版情報: Hepatology.  48  pp.109-118,  2008-07-01.  John Wiley & Sons
URL: http://hdl.handle.net/2297/11569
概要: 金沢大学医薬保健研究域医学系<br />Nonalcoholic steatohepatitis (NASH) is the progressive form of nonalcoholic fatty liver disease and is one of the most common liver diseases in the developed world. The histological findings of NASH are characterized by hepatic steatosis, inflammation, and fibrosis. However, an optimal treatment for NASH has not been established. Tranilast, N-(3′,4′-dimedioxycinnamoyl)- anthranilic acid, is an antifibrogenic agent that inhibits the action of transforming growth factor beta (TGF-β). This drug is used clinically for fibrogenesis-associated skin disorders including hypertrophic scars and scleroderma. TGF-β plays a central role in the development of hepatic fibrosis, and tranilast may thus ameliorate the pathogenesis of NASH. We investigated the effects of tranilast using an established dietary animal model of NASH, obese diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and nondiabetic control Long-Evans Tokushima Otsuka (LETO) rats fed a methionine-deficient and choline-deficient diet. Treatment with 2% tranilast (420 mg/kg/day) for 8 weeks prevented the development of hepatic fibrosis and the activation of stellate cells, and down-regulated the expression of genes for TGF-β and TGF-β-target molecules, including α1 procollagen and plasminogen activator-1. In addition, tranilast attenuated hepatic inflammation and Kupffer cell recruitment, and down-regulated the expression of tumor necrosis factor alpha. Unexpectedly, tranilast ameliorated hepatic steatosis and up-regulated the expression of genes involved in beta-oxidation, such as peroxisome proliferator-activated receptor α and carnitine O-palmitoyltransferase-1. Most of these effects were observed in LETO rats and OLETF rats, which suggest that the action of tranilast is mediated through the insulin resistance-independent pathway. Conclusion: Our findings suggest that targeting TGF-β with tranilast represents a new mode of therapy for NASH. Copyright © 2008 by the American Association for the Study of Liver Diseases. 続きを見る
4.

論文

論文
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
5.

論文

論文
Kita, Yuki ; Takamura, Toshinari ; Misu, Hirofumi ; Ota, Tsuguhito ; Kurita, Seiichiro ; Takeshita, Yumie ; Uno, Masafumi ; Matsuzawa-Nagata, Naoto ; Kato, Ken-ichiro ; Ando, Hitoshi ; Fujimura, Akio ; Hayashi, Koji ; Kimura, Toru ; Ni, Yinhua ; Otoda, Toshiki ; Miyamoto, Ken-ichi ; Zen, Yoh ; Nakanuma, Yasuni ; Kaneko, Shuichi
出版情報: PLoS ONE.  7  pp.e43056-,  2012-09-18.  Public Library of Science
URL: http://hdl.handle.net/2297/32834
概要: Background: Optimal treatment for nonalcoholic steatohepatitis (NASH) has not yet been established, particularly for ind ividuals without diabetes. We examined the effects of metformin, commonly used to treat patients with type 2 diabetes, on liver pathology in a non-diabetic NASH mouse model. Methodology/Principal Findings: Eight-week-old C57BL/6 mice were fed a methionine- and choline-deficient plus high fat (MCD+HF) diet with or without 0.1% metformin for 8 weeks. Co-administration of metformin significantly decreased fasting plasma glucose levels, but did not affect glucose tolerance or peripheral insulin sensitivity. Metformin ameliorated MCD+HF diet-induced hepatic steatosis, inflammation, and fibrosis. Furthermore, metformin significantly reversed hepatic steatosis and inflammation when administered after the development of experimental NASH. Conclusions/Significance: These histological changes were accompanied by reduced hepatic triglyceride content, suppressed hepatic stellate cell activation, and the downregulation of genes involved in fatty acid metabolism, inflammation, and fibrogenesis. Metformin prevented and reversed steatosis and inflammation of NASH in an experimental non-diabetic model without affecting peripheral insulin resistance. © 2012 Kita et al. 続きを見る
6.

論文

論文
Isobe, Yuki ; Sakurai, Masaru ; Kita, Yuki ; Takeshita, Yumie ; Misu, Hirofumi ; Kaneko, Shuichi ; Takamura, Toshinari
出版情報: Journal of Diabetes Investigation.  7  pp.352-358,  2016-05-01.  Wiley
URL: http://hdl.handle.net/2297/43921
概要: Aims/Introduction: To investigate the clinical and anthropometrical parameters that are associated with non-exercise act ivity thermogenesis that is composed of basal energy expenditure (BEE) and diet-induced thermogenesis (DIT) in patients with diabetes. Materials and Methods: Body composition was assessed using bioelectrical impedance, and BEE and DIT were measured using indirect calorimetry in 40 Japanese patients with diabetes. Results: BEE correlated positively with bodyweight, body mass index, fat mass, and fat-free mass, and correlated negatively with age in both men and women. In multivariate logistic regression analysis, BEE correlated positively with both fat mass and fat-free mass independently of sex and age. In addition, DIT correlated positively with bodyweight, body mass index, fat mass and fat-free mass, and correlated negatively with age in women, but not men. Fat-free mass contributed to DIT at least partly, and an aging-related decrease in DIT was observed. The best anthropometric parameter that reflected fat mass and fat-free mass was hip circumference (HC) and calf circumference (CC), respectively, in both men and women. Indeed, both HC (men β = 0.600, P < 0.001; women β = 0.752, P < 0.001) and CC (men β = 0.810, P = 0.012; women β = 0.821, P = 0.002) were correlated with BEE independently of age and sex. In addition, CC (β = 0.653, P = 0.009), but not HC was correlated with DIT significantly only in females, independently of age. Conclusions: HC reflects fat mass and was positively associated with BEE, but not with DIT. In contrast, CC reflects fat-free mass, and was positively associated with BEE in both men and women, and with DIT in women. © 2015 Asian Association for the Study of Diabetes and Wiley Publishing Asia Pty Ltd. 続きを見る
7.

論文

論文
Takazakura, Akiko ; Sakurai, Masaru ; Bando, Yukihiro ; Misu, Hirofumi ; Takeshita, Yumie ; Kita, Yuki ; Shimizu, Akiko ; Hayakawa, Tetsuo ; Kato, Ken-ichiro ; Kaneko, Shuichi ; Takamura, Toshinari
出版情報: Journal of Diabetes Investigation.  6  pp.346-353,  2015-05-01.  Blackwell Publishing
URL: http://hdl.handle.net/2297/45713
概要: Introduction: Several studies have shown that statins suppress the progression of diabetic nephropathy. However, few rep orts have directly compared the renoprotective effects between potent and conventional statins. Materials and Methods: Patients with diabetic nephropathy, selected as those with a serum creatinine level of 0.9-1.5 mg/dL and simultaneously having either microalbuminuria or positive proteinuria, were randomly assigned to one of three groups: a conventional diet therapy group, a group given 10 mg of pravastatin and a group given 10 mg of atorvastatin. Renal function was evaluated before and after a 12-month period of therapy. Results: The atorvastatin group had a significant decrease in low-density lipoprotein cholesterol at 3 months and thereafter compared with the other groups. The urinary albumin-to-creatinine ratio significantly decreased in the atorvastatin group; the degree of this decrease was significantly greater than that in the diet therapy group. The kidney function estimated with cystatin C (CysC) and the estimated glomerular filtration rate calculated from CysC were significantly preserved in the atorvastatin group compared with the pravastatin group. In a multivariate regression analysis, the use of atorvastatin was the only explanatory variable for the changes in CysC; this was independent of changes in low-density lipoprotein cholesterol. Conclusions: Atorvastatin is more effective than pravastatin for the prevention of increase in CysC, and this renoprotective effect was considered to a result of the pleiotropic effect of atorvastatin independent of its lipid-lowering effect. This study was registered with UMIN (no. UMIN 000001774). © 2014 The Authors. 続きを見る
8.

論文

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 pr ognosis 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
9.

論文

論文
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
10.

論文

論文
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