Efeitos do treinamento aeróbico em camundongos ateroscleróticos

Abstract

Atherosclerotic disease is a chronic inflammatory disease that can accelerate vascular cells senescence and aggravate lesions formation. Moderate aerobic exercise improves vascular function and prevents the aggravation of the atherosclerotic process. ApoE-/- mice, an atherosclerotic experimental model, have been an useful tool to understand the process involved in the progression of this disease. The objectives of this study were to verify the performance capacity of apoE-/- mice as well to verify the influence of an exercise program on the vascular cells senescence and the atherosclerotic lesion. ApoE-/- (n=16) and C57BL/6 (n=16) male mice with 4 ½ months old were divided in trained and sedentary groups. Exercise program corresponded: 1hour/day, 50-70% maximal running speed, 5 days/week for 5 weeks. Cholesterol and hemodynamic parameters were also measured. At the end of the exercise protocol, the animals were euthanized; the aorta was removed and incubated in Xgal solution (ph 6.0) for colorimetric assay for senescence, and later for plaque quantification. Results are expressed as mean ± SEM. 2 way-ANOVA with Fisher post hoc was used to statistical analyses, *p< 0,05. Vascular senescence was observed in both groups of apoE-/- mice; and the training did not reduce the atherosclerotic lesion area, although we observed a tendency to reduction in the senescence area. The physical performance of C57 and apoE-/- was not different before the training protocol, but it increased the maximal running speed after the training program, with 36 and 42% increases in the trained C57 and apoE-/-, respectively. ApoE-/- mice were hypercholesterolemic (sedentary: 646±75##, trained: 664±66## mg/dL) compared to C57 (sedentary: 161±16, trained: 102±12 mg/dL), and the training did not modified the cholesterol and the hemodynamic parameters. ApoE-/- mice showed the same capacity of C57 to improve the physical performance. Despite the atherosclerotic lesion area were not reduce with the training protocol, we observed a tendency in the reduction of the senescence area with the training, suggesting a possible effect in the aerobic training in the prevention of the premature senescence