Effects of moderate exercise on the biochemical, physiological, morphological and functional parameters of the aorta in the presence of estrogen deprivation and dyslipidemia: an experimental model.

BACKGROUND: The estrogen deficiency, abnormal lipid profile, weight gain and a sedentary lifestyle are factors associated with the increased prevalence of cardiovascular disease in menopausal women. However, physical exercise practice reduces some of these risk factors. Moreover, it has been shown that exercise has an impact on inflammation, in sympathetic activity and improves endothelial function. AIMS: The present study aims to evaluate the effects of moderate aerobic training on biochemical, morphological and physiological parameters in LDL Knockout mice with estrogen deprivation, evaluating the components of the ascending aortic wall. METHODS: The animals were randomly divided into six groups (n=5): sedentary control (SC), sedentary control ovariectomized (SCO), trained control ovariectomized (TCO), LDL-Knockout sedentary (KS), LDL-Knockout sedentary ovariectomized (KOS) and LDL-Knockout trained ovariectomized (KOT). The trained groups underwent a protocol of moderate training for 4 weeks on a treadmill with speed and progressive load. After training, blood samples were collected for biochemical assessments and the aorta was removed for dissection and histological morphometry study. In addition, the expression of angiotensin-converting enzyme (ACE) and angiotensin II proteins were examined by immunohistochemistry in all groups of animals. RESULTS: Changes of expressions of ACE and angiotensin II were found when the group was subjected to exercise. The concentrations of cholesterol and triglycerides were lower in the groups of animals with estrogen deprivation and dyslipidemia. In animals that performed exercises we found significant increase (p<0.05) in Vv[lam]; decrease in Vv[col] and CWT, and a tendency for decrease both in TS and IMT when compared to the SC groups. The histological morphometry findings showed consistency in the results of the aorta study when the ovariectomized group underwent the exercise protocol. CONCLUSION: We conclude that physical training contributed to reducing vessel rigidity and to improvements in vascular compliance, with the increase in volume density of elastic lamellae in the estrogen-deprived groups who had normal cholesterol levels.

Effects of Moderate Exercise on theBiochemical, Physiological, Morphologicaland Functional Parameters of the Aorta inthe Presence of Estrogen Deprivation andDyslipidemia: an Experimental Model

The estrogen deficiency, abnormal lipid profile, weight gain and a sedentarylifestyle are factors associated with the increased prevalence of cardiovascular disease inmenopausal women. However, physical exercise practice reduces some of these risk factors.Moreover, it has been shown that exercise has an impact on inflammation, in sympatheticactivity and improves endothelial function. Aims: The present study aims to evaluate the effectsof moderate aerobic training on biochemical, morphological and physiological parameters inLDL Knockout mice with estrogen deprivation, evaluating the components of the ascendingaortic wall. Methods: The animals were randomly divided into six groups (n=5): sedentarycontrol (SC), sedentary control ovariectomized (SCO), trained control ovariectomized (TCO),LDL-Knockout sedentary (KS), LDL-Knockout sedentary ovariectomized (KOS) and LDLKnockouttrained ovariectomized (KOT). The trained groups underwent a protocol of moderatetraining for 4 weeks on a treadmill with speed and progressive load. After training, bloodsamples were collected for biochemical assessments and the aorta was removed for dissectionand histological morphometry study. In addition, the expression of angiotensin-convertingenzyme (ACE) and angiotensin II proteins were examined by immunohistochemistry in allgroups of animals. Results: Changes of expressions of ACE and angiotensin II were foundwhen the group was subjected to exercise. The concentrations of cholesterol and triglycerideswere lower in the groups of animals with estrogen deprivation and dyslipidemia. In animals that performed exercises we found significant increase (p<0.05) in Vv[lam]; decrease in Vv[col]and CWT, and a tendency for decrease both in TS and IMT when compared to the SC groups...

The role of cyclooxygenase-2 on endurance exercise training in female LDL-receptor knockout ovariectomized mice.

Estrogen deprivation in postmenopausal women increases cardiovascular risk. Cardiovascular risk as a result of atherosclerosis is able to induce an inflammatory disease as far as cyclooxygenase-2 ( COX-2) expression. The purpose of the study was to investigate the role of COX-2 on exercise training in female mice low-density lipoprotein receptor knockout ( LDL-KO) with or without ovariectomy. A total of 15 female C57BL/6 mice and 15 female LDL-KO mice were distributed into 6 groups: sedentary control, sedentary control ovariectomized, trained control ovariectomized, LDL-KO sedentary, LDL-KO sedentary ovariectomized and LDL-KO trained ovariectomized. The ascending part of the aorta was stained with H&E and COX-2 expression was assessed by immunohistochemistry. Results revealed that ovariectomy as well as exercise training were not able to induce histopathological changes in mouse aorta for all groups investigated. LDL-KO mice demonstrated plaque containing cholesterol clefts, foamy histiocytes and mild inflammatory process for all groups indistinctly. Ovariectomy induced a strong immunoexpression in atherosclerosis lesion of LDL-KO mice. Nevertheless, a down-regulation of COX-2 expression was detected in LDL-KO trained ovariectomized when compared to LDL-KO sedentary. Our results are consistent with the notion that exercise training is able to modulate COX-2 expression in LDL-KO mice as a result of COX-2 down-regulation.