Effects of Aerobic Interval Exercise Training on Cardiomyocytes and Cardiac Fibroblasts

According to the statistical results of our national Ministry of Health and Welfare, in 2002 a total of 11,441 people died of heart disease in 2002 (9.46% of all deaths). While there were 16,513 people died of heart disease (10.9% of all deaths) in 2011. An increase of 40% of people in Taiwan died of heart disease in a decade. A series of cardiac-related diseases reduce cardiomyocytes and cause remodeling induced by apoptosis and autophagy. In this case, cardiac fibroblasts are activated to migrate into the injured area and substituted death cardiomyocytes for scar tissue. Cardiac fibrosis can be divided into a reversible fibrosis (reactive interstitial fibrosis and infiltrative interstitial fibrosis), and irreversible fibrosis of replacement fibrosis. Heart size, shape, and response to mechanical, chemical, or electrical signals will change in the irreversible cardiac fibrosis, and ultimately lead to the loss of heart function. Exercise training for cardiac patients has been advocated recently. Changes of serum components will affect the cardiomyocytes physiology based on previous reports. We hypothesize that appropriate exercise training can affect hemodynamics and blood components, which may inhibit fibroblast activity, improve myocardial function. A decrease in the reversible cardiac fibrosis and an increase of cardiac contractility may follow the above alterations. Impacts of serum in healthy subjects and cardiac patients on cardiomyocytes and cardiac fibroblasts before exercise training was measured in the first year experiments. Cardiac magnetic resonance imaging, renal function, cholesterol, blood sugar, BNP, and proteomic studies in cardiac patients before exercise testing were also analyzed. In the second year, similar works will be done in cardiac patients heart patients after 36 times of aerobic interval exercise training. Finally, identification of the altered proteins after exercise training in cardiac patients will be done in the third year. We will verify the impacts of the altered proteins on cardiomyocytes and cardiac fibroblasts. Similar age of twenty ischemic heart patients and healthy subjects will be recruited in the first year. Cardiac magnetic resonance imaging, blood examinations (kidney function, cholesterol, blood sugar, and BNP), and cardiopulmonary exercise testing will be done for cardiac patients before exercise training. In the meantime, effects of 10% serum of healthy subjects and cardiac patients on cardiac myoblasts (H9C2 cell line) and cardiac fibroblasts (HCF-av cells) are going to be measured with the electric cell-substrate impedance sensing technique (ECIS). Cell-cell junction resistance (Rb), cell-substratum resistance (α), and membrane capacitance (Cm) will be evaluated in the above cells for 24 hours. The patient serum is analyzed with proteomic studies. Actin and microtubule polymerizations in cardiac fibroblasts treated with healthy and cardiac patients serum for 24 hours will be examined with fluorescent microscopy. In the second year, every cardiac patient will have 36 times of aerobic interval exercise training (40% and 80% peak workload). Similar studies will be done for cardiac patients after the exercise training as the first year. Finally, changes of proteins caused by the above exercise training in cardiac patients will be assessed and verified. Effective way to assess cardiac cells can be established, which becomes an indicator for exercise prescription.

Project ID:PC10408-1255
External Project ID:MOST104-2314-B182-004