Diabetes
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Diabetes 55:2371-2378, 2006
DOI: 10.2337/db06-0268
© 2006 by the American Diabetes Association
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Purchase Article
Right arrow View Shopping Cart
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Taniguchi, Y.
Right arrow Articles by Saikawa, T.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Taniguchi, Y.
Right arrow Articles by Saikawa, T.
Social Bookmarking
Add to CiteULike   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?

Pioglitazone but Not Glibenclamide Improves Cardiac Expression of Heat Shock Protein 72 and Tolerance Against Ischemia/Reperfusion Injury in the Heredity Insulin-Resistant Rat

Yayoi Taniguchi1, Tatsuhiko Ooie1, Naohiko Takahashi2, Tetsuji Shinohara2, Mikiko Nakagawa1, Hidetoshi Yonemochi1, Masahide Hara2, Hironobu Yoshimatsu2, and Tetsunori Saikawa1

1 Department of Cardiovascular Science, Faculty of Medicine, Oita University, Oita, Japan
2 Department of Internal Medicine 1, Faculty of Medicine, Oita University, Oita, Japan

Address correspondence and reprint requests to Naohiko Takahashi, MD, PhD, Department of Internal Medicine 1, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Yufu, Oita 879-5593, Japan. E-mail: takanao{at}med.oita-u.ac.jp

Abbreviations: CPP, coronary perfusion pressure; GGA, geranylgeranylacetone; HSP, heat shock protein; LVDP, left ventricular developed pressure; OGTT, oral glucose tolerance test; PI3, phosphatidylinositol 3; PPAR-{gamma}, peroxisome proliferator–activated receptor-{gamma}; STZ, streptozotocin

We tested the hypothesis that pioglitazone could restore expression of heat shock protein (HSP)72 in insulin-resistant rat heart. At 12 weeks of age, male Otsuka Long-Evans Tokushima Fatty (OLETF) rats and control (LETO) rats were treated with pioglitazone (10 mg · kg–1 · day–1) or glibenclamide (5 mg · kg–1 · day–1) for 4 weeks. Thereafter, hyperthermia (43°C for 20 min) was applied. In response to hyperthermia, the activation of serine/threonine kinase Akt depending on phosphatidylinositol 3 (PI3) kinase was necessary for cardiac expression of HSP72. Hyperthermia-induced activation of Akt and HSP72 expression were depressed in OLETF rat hearts. Pioglitazone but not glibenclamide improved insulin sensitivity in OLETF rats, which was associated with the restoration of Akt activation and HSP72 expression. In experiments with isolated perfused heart, reperfusion-induced cardiac functional recovery was suppressed in OLETF rat hearts, which was improved by pioglitazone but not glibenclamide. Our results suggest that PI3 kinase–dependent Akt activation, an essential signal for HSP72 expression, is depressed in the heart in insulin-resistant OLETF rats, and the results suggest also that the restoration of HSP72 expression and tolerance against ischemia/reperfusion injury by treatment with pioglitazone might be due to an improvement of insulin resistance, leading to restoration of impaired PI3 kinase–dependent Akt activation in response to hyperthermia.


Add to CiteULike CiteULike   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Diabetes Diabetes Care Clinical Diabetes Diabetes Spectrum
Copyright © 2006 by the American Diabetes Association.