TY - JOUR
T1 - Electrocardiographic changes with the onset of diabetes and the impact of aerobic exercise training in the Zucker Diabetic Fatty (ZDF) rat
AU - VanHoose, Lisa
AU - Sawers, Youssef
AU - Loganathan, Rajprasad
AU - Vacek, James L.
AU - Stehno-Bittel, Lisa
AU - Novikova, Lesya
AU - Al-Jarrah, Muhammed
AU - Smirnova, Irina V.
N1 - Funding Information:
We thank Aziz Shaibekov and Purvi Patel for helping with animal exercise training. National Institutes of Health Grant Number P20 RR016475 from the INBRE Program of the National Center for Research Resources (IVS) provided resources for conducting the study. The U.S. Department of Health and Human Service through a National Research Service Award from the National Heart, Lung, and Blood Institute (LVH) supported analysis and interpretation of data and manuscript development. National Institute of Child Health and Human Development Grant Number HD02528 supported core facility services.
PY - 2010/9/22
Y1 - 2010/9/22
N2 - Background: Early markers of diabetic autonomic neuropathy (DAN) in an electrocardiogram (ECG) include elevated R wave amplitudes, widening of QTc intervals and decreased heart rate variability (HRV). The severity of DAN has a direct relationship with mortality risk. Aerobic exercise training is a common recommendation for the delay and possible reversal of cardiac dysfunction. Limited research exists on ECG measures for the evaluation of aerobic exercise training in Zucker Diabetic Fatty (ZDF) rat, a model of type 2 diabetes. The objective of this study was to assess whether aerobic exercise training may attenuate diabetes induced ECG changes.Methods: Male ZDF (obese fa/fa) and control Zucker (lean fa/+) rats were assigned to 4 groups: sedentary control (SC), sedentary diabetic (SD), exercised control (EC) and exercised diabetic (ED). The exercised groups began 7 weeks of treadmill training after the development of diabetes in the ED group. Baseline (prior to the training) and termination measurements included body weight, heart weight, blood glucose and glycated hemoglobin levels and ECG parameters. One way repeated measures ANOVA (group) analyzed within and between subject differences and interactions. Pearson coefficients and descriptive statistics described variable relationships and animal characteristics.Results: Diabetes caused crucial changes in R wave amplitudes (p < 0.001), heart rate variability (p < 0.01), QT intervals (p < 0.001) and QTc intervals (p < 0.001). R wave amplitude augmentation in SD rats from baseline to termination was ameliorated by exercise, resulting in R wave amplitude changes in ED animals similar to control rats. Aerobic exercise training neither attenuated QT or QTc interval prolongation nor restored decreases in HRV in diabetic rats.Conclusion: This study revealed alterations in R wave amplitudes, HRV, QT and QTc intervals in ZDF rats. Of these changes, aerobic exercise training was able to correct R wave amplitude changes. In addition, exercise has beneficial effect in this diabetic rat model in regards to ECG correlates of left ventricular mass.
AB - Background: Early markers of diabetic autonomic neuropathy (DAN) in an electrocardiogram (ECG) include elevated R wave amplitudes, widening of QTc intervals and decreased heart rate variability (HRV). The severity of DAN has a direct relationship with mortality risk. Aerobic exercise training is a common recommendation for the delay and possible reversal of cardiac dysfunction. Limited research exists on ECG measures for the evaluation of aerobic exercise training in Zucker Diabetic Fatty (ZDF) rat, a model of type 2 diabetes. The objective of this study was to assess whether aerobic exercise training may attenuate diabetes induced ECG changes.Methods: Male ZDF (obese fa/fa) and control Zucker (lean fa/+) rats were assigned to 4 groups: sedentary control (SC), sedentary diabetic (SD), exercised control (EC) and exercised diabetic (ED). The exercised groups began 7 weeks of treadmill training after the development of diabetes in the ED group. Baseline (prior to the training) and termination measurements included body weight, heart weight, blood glucose and glycated hemoglobin levels and ECG parameters. One way repeated measures ANOVA (group) analyzed within and between subject differences and interactions. Pearson coefficients and descriptive statistics described variable relationships and animal characteristics.Results: Diabetes caused crucial changes in R wave amplitudes (p < 0.001), heart rate variability (p < 0.01), QT intervals (p < 0.001) and QTc intervals (p < 0.001). R wave amplitude augmentation in SD rats from baseline to termination was ameliorated by exercise, resulting in R wave amplitude changes in ED animals similar to control rats. Aerobic exercise training neither attenuated QT or QTc interval prolongation nor restored decreases in HRV in diabetic rats.Conclusion: This study revealed alterations in R wave amplitudes, HRV, QT and QTc intervals in ZDF rats. Of these changes, aerobic exercise training was able to correct R wave amplitude changes. In addition, exercise has beneficial effect in this diabetic rat model in regards to ECG correlates of left ventricular mass.
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U2 - 10.1186/1475-2840-9-56
DO - 10.1186/1475-2840-9-56
M3 - Article
C2 - 20860788
AN - SCOPUS:77956841912
SN - 1475-2840
VL - 9
JO - Cardiovascular Diabetology
JF - Cardiovascular Diabetology
M1 - 56
ER -