ABC | Volume 112, Nº5, May 2019

Original Article Effting et al RE Effects: heart and obesity Arq Bras Cardiol. 2019; 112(5):545-552 Figure 1 – A – Total body weight during the study; B - Delta (body weight variation in relation to the start of the study); C - weight comparison between the 1st week (start), 18 th week (pre-exercise) and 26 th week (post-exercise); D - Glucose decay rate in the insulin tolerance test (kITT). Figure A, B and D - *p < 0.05 vs. respective untrained of the same period, # p < 0.05, ## p < 0.01 and ### p < 0,001 vs. respective SD of the same period; & p < 0.05 vs. same group of the previous week. Figure C - *p < 0.001 vs. respective untrained of the same period; # p < 0.01 and ## p < 0.001 vs. respective SD of the same period; & p < 0.05, && p < 0.001 vs. same group of the previous week. A B C D 65 35 30 25 20 15 5 8 7 6 5 4 3 2 1 10 60 55 45 35 50 40 70 60 50 40 30 20 10 0 2 4 6 8 10 12 14 16 18 20 22 24 26 Total body weight (g) Body weight (g) kITT (%/min) Delta body weight (g) Weeks Weeks SD SD+RE DIO DIO+RE SD SD+RE DIO DIO+RE SD SD+RE DIO DIO+RE (DIO) (DIO+RE) Exercise # ## ### ### ### ### * * SD 0 DIO 0 SD 18 DIO 18 SD 26 DIO 26 1 st week (Start) 18 th week (Pre-exercise) 26 th week (Post-exercise) & && # && # & # * Untrained Resistance training 3ª 6ª 10ª 14ª 18ª 22ª 26ª # # & # & # & # # # ### ## * ## # * * # Pre-exercise Post-exercise CAT Activity The results observed in Figure 2D show a reduction in CAT activity in trained animals (SD + RE, p < 0.001 and SD, DIO + RE, p < 0.01 vs . untrained animals). On the other hand, the HFD animals also showed a decrease in CAT (p < 0.05), but only when compared to the SD animals. GSH Total glutathione levels were not significantly altered in both the interventions used in the present study (diet and exercise) (Figure 2E). Inflammatory Parameter The levels of TNF- α were used as an inflammatory indicator in cardiac tissue and the results observed in figure 2F showed an increase in TNF- α content in DIO animals (p < 0.05), which was significantly reduced (p < 0.05) after the intervention with resistance physical exercise (DIO + RE). Discussion Studies have shown that the consumption of a diet rich in fat, concomitant with a sedentary lifestyle, can trigger several health problems 21,22 with a significant impact on the cardiovascular system. Therefore, experimental studies have been used to study the cellular effects of a high fat diet. 6,23,24 The results of body weight and ITT showed that the adopted experimental model was effective in increasing weight and causing insulin resistance. Increased body weight has been associated to inflammatory changes and oxidative stress, and both these alterations to insulin resistance in skeletal muscle, 25,26 but recent studies have also shown that cardiac cells are also susceptible to weight gain, by elevating inflammatory mediators and oxidative stress. 6,23,24,27,28 In this context, previous studies suggested an important role of physical exercise, specifically aerobic or endurance, on the biochemical and molecular changes occurring in the myocardium as the result of a diet rich in fat. 3,7 However, these effects depend on the characteristics of the exercise, such as duration, frequency, intensity and type. 548