Author(s)

Ikuo Yokoyama, Toshiyuki Moritan, Yusuke Inoue

Department of Cardiovascular Medicine, Clinical Research Center, Sanno Hospital of International University of Health and Welfare, Tokyo, Japan.
Department of Clinical Engineering, Faculty of Medical Engineering, Suzuka University of Medical Science, Suzuka, Japan.
JapanDepartment of Radiology, Institute of Medical Science, Graduate School of Medicine University of Tokyo, Tokyo, Japan.

Background: Existence of myocardial insulin resistance (IR) has been reported in type II diabetics (T2- DM) and coronary artery disease (CAD). Improvement in heart and skeletal muscle IR after thiazolidinedione’s therapy was reported in T2DM and CAD. However effects of troglitazone therapy (TRO) on myocardial IR remain uncertain. To clarify heart and skeletal muscle and whole body IR in T2DM without CAD by TRO to clarify whether TRO would provide different results. Methods: We analyzed data on 15 T2DM patients who underwent dynamic PET with ¹⁸F-FDG under insulin clamping before and during TRO (200 mg/day) and 17 controls. Results: Whole body glucose disposal rate (WBGR mg/min/kg) in T2DM before TRO (3.41 ± 1.72) was significantly lower than in controls (9.76 ± 2.97, p < 0.01) as was the skeletal muscle glucose utilization rate (SMGU mg/min/kg); T2DM (0.367 ± 0.217) vs. controls (1.34 ± 0.613, p < 0.01) and myocardial glucose utilization rate (MGU mg/min/kg; T2DM 5.86 ± 2.03 vs. controls 7.34 ± 1.80, p < 0.05). WBGR in T2DM during TRO (5.17 ± 2.75, p < 0.05) was significantly higher than that before TRO, as was the SMGU (0.782 ± 0.20, p < 0.05). The MGU in T2DM during TRO (6.59 ± 0.72) was comparable with that before TRO. Conclusion: Myocardial IR response to TRO differed from that in skeletal muscle and the whole body in T2DM without CAD.

Insulin Resistance; Myocardial Insulin Resistance; Glucose Metabolism; Skeletal Muscle; Type II Diabetes Mellitus; 18F-FDG; PET

Yokoyama, I. , Moritan, T. and Inoue, Y. (2012) Skeletal muscle and whole body insulin resistance but not cardiac muscle insulin resistance could be improved by troglitazone therapy within 12 weeks in type-2 diabetes. Journal of Biomedical Science and Engineering, 5, 829-835. doi: 10.4236/jbise.2012.512A105.