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| Author(s): |
Mariana Janini Gomes
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Botucatu. 2019-03-18. |
| Institution: | Universidade Estadual Paulista (Unesp). Faculdade de Medicina. Botucatu |
| Defense date: | 2019-03-01 |
| Advisor: | Marina Politi Okoshi |
| Abstract | |
Skeletal muscle changes contribute to reduced physical performance after myocardial infarction (MI). Exercise has been recommended to stable patients. However, the effects of resistance exercise after MI are not clear. We compared the effects of two types of exercise, aerobic and resistance, initiated during compensated cardiac remodeling, in gastrocnemius muscle of infarcted rats. Methods: Three months after MI induction, Wistar rats were divided into four groups: Sham (n=20); sedentary MI (MI-S; n=9); aerobic exercised MI (MI-A; n=9); and resistance exercised MI (MI-R; n=13). Exercised rats trained three times a week for 12 weeks on treadmill or vertical ladder. Energy metabolism, oxidative stress markers, and antioxidant enzyme activities were assessed by spectrophotometry. Markers of satellite cells activation (MyoD, NCAM, and myosin heavy chain neonatal isoform) were assessed by immunofluorescence or Western blot (Pax-7). Statistical analyzes: ANOVA or Mann Whitney. Results: Aerobic physical capacity was greater in MI-A group and maximum carrying load higher in MI-R. Cardiac structures and left ventricular function evaluated by echocardiogram did not differ between the infarcted groups. Histological analyzes showed that MI size and gastrocnemius cross sectional area did not differ between infarcted groups. Oxygen reactive species production was higher in MI-S than Sham and lipid hydroperoxide concentration was lower in MI-A than the other groups. Catalase activity was higher and glutathione peroxidase activity lower in infarcted groups than Sham. Superoxide dismutase activity was higher in Sham and MI-R than MI-S. Activity of enzymes of skeletal muscle metabolism did not differ between groups, except by an increase in piruvate kinase in MI-S than the other groups, and β-hydroxyacyl CoA dehydrogenase in MI-S than Sham. Satellite cell activation and protein expression of MAPK and NF-κB did not differ between groups. Conclusion: Aerobic and resistance exercise improves physical capacity and maximum load, respectively, without changing echocardiographic parameters of infarcted rats. Myocardial infarction increases oxygen reactive species production and changes activity of antioxidant enzymes of glucose and fatty acid enzymes metabolism. Aerobic exercise reduces muscle lipid hydroperoxide concentration and attenuates glutathione peroxidase activity change, being superior to resistance exercise against oxidative stress. (AU) | |
| FAPESP's process: | 14/23592-3 - Influence of aerobic or resistance physical exercise on skeletal muscle of rats with myocardial infarction |
| Grantee: | Mariana Janini Gomes |
| Support Opportunities: | Scholarships in Brazil - Doctorate |