Τίτλος:
Thyroid hormone improves the mechanical performance of the post-infarcted diabetic myocardium: A response associated with up-regulation of Akt/mTOR and AMPK activation
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Objective Thyroid hormone (TH) is shown to be protective against cardiac and pancreatic injury. Thus, this study explored the potential effects of TH treatment on the functional status of the postinfarcted diabetic myocardium. Diabetic patients have worse prognosis after acute myocardial infarction (AMI). Materials/Methods AMI was induced by left coronary ligation in rats previously treated with 35 mg/kg streptozotocin (STZ), (DM-AMI). TH treatment was initiated at 2 weeks after AMI and continued for 6 weeks (DM-AMI + TH), while sham-operated animals served as control (DM-SHAM). Results TH treatment increased cardiac mass, improved wall stress and favorably changed cardiac geometry. TH significantly increased echocardiographic left ventricular ejection fraction (LVEF%): [54.2 (6.5) for DM-AMI + TH vs 37 (2.0) for DM-AMI, p < 0.05]. TH treatment resulted in significantly increased insulin and decreased glucose levels in serum. The ratios of phosphorylated (p)-Akt/total Akt and p-mTOR/total mTOR were increased 2.0 fold and 2.7 fold in DM-AMI + TH vs DM-AMI respectively, p < 0.05. Furthermore, the ratio of p-AMPK/total AMPK was found to be increased 1.6 fold in DM-AMI + TH vs DM-AMI, p < 0.05. Conclusion TH treatment improved the mechanical performance of the post-infarcted myocardium in rats with STZ-induced diabetes, an effect which was associated with Akt/mTOR and AMPK activation. © 2013 Elsevier Inc.
Συγγραφείς:
Mourouzis, I.
Giagourta, I.
Galanopoulos, G.
Mantzouratou, P.
Kostakou, E.
Kokkinos, A.D.
Tentolouris, N.
Pantos, C.
Περιοδικό:
Metabolism: Clinical and Experimental
Λέξεις-κλειδιά:
insulin; protein kinase B; thyroid hormone; glucose blood level; hydroxymethylglutaryl coenzyme A reductase kinase; mTOR protein, rat; protein kinase B; target of rapamycin kinase; thyroid hormone, acute heart infarction; animal experiment; animal model; animal tissue; article; controlled study; coronary artery ligation; geometry; glucose blood level; heart left ventricle ejection fraction; heart muscle; male; mass; nonhuman; priority journal; rat; streptozocin diabetes; upregulation; wall stress; animal; blood; cardiomegaly; Diabetes Complications; diabetes mellitus; drug effects; heart; heart muscle; heart ventricle; metabolism; Myocardial Infarction; pathophysiology; signal transduction; upregulation; Wistar rat, AMP-Activated Protein Kinases; Animals; Blood Glucose; Cardiomegaly; Diabetes Complications; Diabetes Mellitus; Heart; Heart Ventricles; Insulin; Male; Myocardial Infarction; Myocardium; Proto-Oncogene Proteins c-akt; Rats; Rats, Wistar; Signal Transduction; Thyroid Hormones; TOR Serine-Threonine Kinases; Up-Regulation
DOI:
10.1016/j.metabol.2013.05.008
