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SPIRIT checklist. (DOC 121 kb)

Fundamento: O treinamento aeróbio intervalado produz maior benefício na função cardiovascular comparado ao treinamento aeróbio contínuo. Objetivo: O presente estudo teve como objetivo analisar os efeitos de ambas as modalidades nas respostas hemodinâmicas de ratos sadios. Métodos: Ratos machos foram distribuídos aleatoriamente em três grupos: exercício contínuo (EC, n = 10); exercício intervalado (EI, n = 10); e controle (C, n = 10). A sessão do grupo EC consistiu em 30 min à intensidade de 50% da velocidade máxima (Vel Máx). O grupo EI realizou 30 min, incluindo três períodos de 4 min a 60% da Vel Máx intercalados com 4 min de recuperação a 40% da Vel Máx. Frequência Cardíaca (FC), Pressão Arterial (PA) e Duplo Produto (DP) foram medidos antes, durante e após o exercício. Resultados: Os grupos EC e EI apresentaram aumento da PA sistólica e DP durante o exercício em comparação ao repouso. Após o término do exercício, o grupo EC mostrou menor resposta da PA sistólica e do DP em relação ao repouso, enquanto o grupo EI apresentou menor PA sistólica e PA média. No entanto, somente no grupo EI a FC e o DP apresentaram menor resposta na recuperação. Conclusão: Uma sessão de exercício intervalado em ratos sadios induziu respostas hemodinâmicas similares durante o exercício às obtidas em exercício contínuo. Na recuperação, o exercício intervalado promoveu maiores reduções no esforço cardíaco do que em sessões contínuas de exercício. Background: Aerobic interval exercise training has greater benefits on cardiovascular function as compared with aerobic continuous exercise training. Objective: The present study aimed at analyzing the effects of both exercise modalities on acute and subacute hemodynamic responses of healthy rats. Methods: Thirty male rats were randomly assigned into three groups as follows: continuous exercise (CE, n = 10); interval exercise (IE, n = 10); and control (C, n = 10). Both IE and CE groups performed a 30-minute exercise session. The IE group session consisted of three successive 4-minute periods at 60% of maximal velocity (Max Vel), with 4-minute recovery intervals at 40% of Max Vel. The CE group ran continuously at 50% of Max Vel. Heart rate (HR), blood pressure(BP), and rate pressure product (RPP) were measured before, during and after the exercise session. Results: The CE and IE groups showed an increase in systolic BP and RPP during exercise as compared with the baseline values. After the end of exercise, the CE group showed a lower response of systolic BP and RPP as compared with the baseline values, while the IE group showed lower systolic BP and mean BP values. However, only the IE group had a lower response of HR and RPP during recovery. Conclusion: In healthy rats, one interval exercise session, as compared with continuous exercise, induced similar hemodynamic responses during exercise. However, during recovery, the interval exercise caused greater reductions in cardiac workload than the continuous exercise.

Submitted by Boris Flegr (boris@uerj.br) on 2021-01-05T18:41:54Z No. of bitstreams: 1 Thiago Teixeira Guimaraes_tese.pdf: 4465279 bytes, checksum: 30bcfdff3a2905c4b4e7a73ee6134335 (MD5) Made available in DSpace on 2021-01-05T18:41:54Z (GMT). No. of bitstreams: 1 Thiago Teixeira Guimaraes_tese.pdf: 4465279 bytes, checksum: 30bcfdff3a2905c4b4e7a73ee6134335 (MD5) Previous issue date: 2019-10-02 Introduction: Physical inactivity is one of the main causes attributed to the development of chronic noncommunicable diseases. However, strenuous exercise loads can develop cellular immunosuppression, impairing performance and health. Aim: To investigate the effect of aerobic training at different volumes on the modulation of function of macrophages function infected in vitro with Leishmania major and on the development of infection in the Balb/c in vivo model. Methods: The total sample consisted of 89 young male BALB/c mice, with an average age of six weeks. Two similar experiments with in vitro infection were performed with 71 mice. A third experiment with in vivo infection was performed with 18 mice. The 71 mice from the in vitro experiments were divided into five experimental groups: sedentary control (SED), low volume (BV), medium volume (MV), high volume (AV) and very high volume ( MAV). With the exception of SED, the other groups underwent 10 weeks of swimming training, ranging in intensity from zero to 3.5% of body mass, duration of 20 to 120 minutes per session and frequency of two to five times a week. The tapering group (POL) was formed at the end of the tenth week of training from the MAV group. Active rest in this group lasted two weeks, in which the frequency, duration and intensity of the sessions were reduced. The physical capacity test was performed before, in the middle and at the end of the 10 week training period, as well at the end of the tapering period for the POL group. After euthanasia, macrophages were obtained by peritoneal wash and maintained in the presence of Leishmania major promastigotes in vitro. The levels of cytokines TNF, MCP-1, IL-10 and IL-6 were measured in macrophage cultured cell supernatants, besides the infection index. The 18 training mice with in vivo infection were divided into three experimental groups: sedentary control (n=5), high volume (n=7) and high non-periodized volume (n=6). The swimming training period had a total duration of 12 weeks. The following variables were analyzed: nitric oxide production, lesion development, late hypersensitivity response (DTH), parasitic load and lymph node weight. Results: In the in vitro experiments, the physical capacity test after five weeks revealed the best performance for the MAV group (P

Submitted by Boris Flegr (boris@uerj.br) on 2021-01-05T18:49:58Z No. of bitstreams: 1 Gabriel da Silva Gama - Dissertacao.pdf: 983220 bytes, checksum: a7984c1490bcce2bac32f474d056045b (MD5) Made available in DSpace on 2021-01-05T18:49:58Z (GMT). No. of bitstreams: 1 Gabriel da Silva Gama - Dissertacao.pdf: 983220 bytes, checksum: a7984c1490bcce2bac32f474d056045b (MD5) Previous issue date: 2019-08-26 Introduction: People living with HIV frequently present autonomic dysfunction at rest and during recovery after exercise. Considering that autonomic nervous system is an important neuromodulator that regulates both heart rate and arterial pressure, it is expected a full integrity of this system to achieve a proper cardiovascular response during exercise. Thus, it would be reasonable to assume that HIV-infected patients exhibit altered neurovascular responses to exercise. Objective: Evaluate the influence of muscle metaboreflex upon the pressor response during handgrip exercise in men living with HIV/AIDS. Methods: Pressor and heart rate responses were evaluated during metaboreflex activation by means of the post-exercise muscle ischemia (PEMI) method and control exercise session (CER) in 17 HIV-infected patients and 21 healthy controls. The protocols were performed randomly on the same day, being both sessions composed of 12 min, as follows: a) 3 min at rest, b) 3 min of dynamic handgrip exercise at 30% of maximal voluntary contraction, c) 3 min of recovery post-exercise with vascular occlusion (occlusion only in PEMI), and d) 3 min of recovery post-exercise without vascular occlusion. To assess the metaboreflex gain, the difference between PEMI and CER in the last 2 minutes of recovery post-exercise with vascular occlusion were calculated for blood pressure and heart rate. Results: Systolic and mean blood pressure (p < 0.01) were superior in the last 2 min of recovery with vascular occlusion at PEMI in relation to CER for both groups. No difference was found between groups for systolic, mean and diastolic blood pressure, and heart rate (p > 0.05). However, metaboreflex gain (PEMI CER) for systolic blood pressure in HIV-infected patients were lower than healthy controls (HIV: 4.05 ± 4.63 vs Controls: 7.61 ± 3.99 mmHg; P = 0.01). Conclusion: Men living with HIV/AIDS may exhibit impaired muscle metaboreflex sensibility to dynamic handgrip exercise Introdução: Pessoas vivendo com HIV frequentemente apresentam disfunção autonômica no repouso e na recuperação após exercício. Tendo em vista que o sistema nervoso autônomo é um importante neuromodulador que controla a frequência cardíaca e pressão arterial, pressupõem-se que seja necessária total integridade desse sistema para obtenção de uma resposta cardiovascular adequada ao exercício. Partindo-se dessa premissa, seria razoável supor que pacientes infectados por HIV apresentam respostas cardiovasculares alteradas durante o exercício físico. Objetivo: Avaliar a influência do metaborreflexo muscular sobre as respostas pressóricas induzidas pelo exercício de preensão manual em homens vivendo com HIV/AIDS. Métodos: Foram avaliadas as respostas pressóricas e de frequência cardíaca durante ativação do metaborreflexo através do método de isquemia muscular pós-exercício (PEMI) e sessão controle do exercício (CER) em 17 pacientes infectados pelo HIV e 21 controles saudáveis. Os protocolos eram realizados no mesmo dia, em ordem aleatória, sendo ambos compostos de 12 min, da seguinte forma: a) 3 min em repouso, b) 3 min de exercício dinâmico de preensão manual a 30% da contração voluntária máxima, c) 3 min de recuperação pós-exercício com oclusão vascular (oclusão apenas no PEMI), e d) 3 min de recuperação pós-exercício sem oclusão vascular. Para avaliação do ganho metaborreflexo, foi calculada a diferença entre PEMI e CER obtida nos 2 últimos minutos da recuperação com oclusão vascular para os valores de pressão arterial e frequência cardíaca. Resultados: A pressão arterial sistólica e média (p < 0,01) foram superiores nos 2 últimos minutos da recuperação com oclusão vascular em PEMI em relação ao mesmo momento do CER em ambos os grupos. Não foram encontradas diferenças significativas entre os grupos para pressão arterial sistólica, média, diastólica, e frequência cardíaca (p > 0,05). No entanto, o ganho metaborreflexo (PEMI CER) para a pressão arterial sistólica nos pacientes com HIV foi inferior ao apresentado pelos controles saudáveis (HIV: 4,05 ± 4,63 vs Controles: 7,61 ± 3,99 mmHg; p = 0,01). Conclusão: Homens vivendo com HIV/AIDS podem apresentar prejuízo da sensibilidade metaborreflexa ao exercício dinâmico de preensão manual

Submitted by Boris Flegr (boris@uerj.br) on 2021-01-05T18:49:55Z No. of bitstreams: 1 Guilherme de Oliveira Franca_Dissertacao.pdf: 666091 bytes, checksum: 4e42c77e03bd13ae63b501af734e0c36 (MD5) Made available in DSpace on 2021-01-05T18:49:55Z (GMT). No. of bitstreams: 1 Guilherme de Oliveira Franca_Dissertacao.pdf: 666091 bytes, checksum: 4e42c77e03bd13ae63b501af734e0c36 (MD5) Previous issue date: 2019-03-18 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Aim: To compare the cardioprotective effect of isocaloric sessions of high intensity interval exercise and continuous exercise in obese animals following myocardial injury. Methods: Adult male wistar rats were divided into two groups, according to the diet used: 1) standard rat chow (CTR);or 2) high fat diet (HFD). After 20 weeks of diet, animals fed with HFD were randomly subdivided into 3 groups: 1) sedentary (HFD-SED); 2) continuous exercise (HFD-CONT); and 3) high intensity interval exercise (HFD-HIIT). Then, HFD-CONT and HFD-HIIT underwent4isocaloric aerobic exercise sessions, in which HFD-CONT maintained the intensity at 50% of maximal oxygen uptake reserve (VO2R) while HFD-HIIT altered 3 min of 60% VO2R and 4 min of 80% VO2R. To equalize exercise volume, the duration of exercise sessions of each animal was calculated to elicit 5 kcal of energy expenditure. After 24h of exercise sessions or sedentarism, all animals underwent ischemia reperfusion injury in an isolated heart model (Langendorff). Results: Animals fed with high fat diet, before performing exercise, exhibited higher mean and diastolic blood pressure, fasting blood glucose, total body mass, fat percentage and lower lean body mass than CTR. Curiously, four sessions of continuous or HIIT exercise restored muscle atrophy induced by high fat diet, as only HFD-SED presented lower mass of gastrocnemius and quadriceps muscles in relation to CTR. Concerning the cardiac function following myocardial injury, HFD-HIIT group presented higher percentage of left ventricle developed pressure related to baseline when compared to the other groups. However, left ventricle infarct area was similar among groups. Conclusion: Four sessions of physical exercise, either continuous or HIIT, restored muscle atrophy induced by high fat diet. However, only the HIIT protocol afforded cardioprotection against ischemia reperfusion injury in obese animals Objetivo:Comparar o efeito cardioprotetor de sessões isocalóricas de exercício aeróbio intervalado de alta intensidade e contínuo em animais obesos após lesão miocárdica.Métodos: Ratos wistar machos adultos foram divididos em dois grupos, de acordo com a dieta utilizada: 1) ração comercial padrão(CTR); e 2) dieta hiperlipídica (HFD). Após 20 semanas de dieta, os animais alimentados com HFD foram randomicamente subdivididos em 3 grupos: 1) sedentário (HFD-SED); 2) exercício contínuo (HFD-CONT); e 3) exercício intervalado de alta intensidade (HFD-HIIT). Em seguida, os grupos HFD-CONT e HFD-HIIT foram submetidos a 4 sessões isocalóricas de exercício físico, sendo que o HFD-CONT manteve a intensidade a 50% do consumo máximo de oxigênio de reserva (VO2R), enquanto o HFD-HIIT alternou a intensidade de 60%VO2R (3 min) e 80%VO2R (4 min). Para equilibrar o volume do exercício, a duração da sessão de exercício de cada animal foi calculada para elicitar um dispêndio energético de 5kcal. Após 24h das sessões de exercício ou sedentarismo, todos os grupos foram submetidos a lesão por isquemia reperfusão em modelo de coração isolado (Langendorff). Resultados: Os animais submetidos a dieta hiperlipídica, antes da realização do exercício, apresentaram maior pressão arterial média e diastólica, glicemia de jejum, massa corporal total e percentual de gordura e menor massa magra em relação ao grupo CTR. Curiosamente, quatro sessões de exercício contínuo ou HIIT reverteram a atrofia muscular causada pela dieta hiperlipídica, uma vez que somente o grupo HFD-SED apresentou menor massa de músculo gastrocnêmio e quadríceps em relação ao CTR. Em relação a função cardíaca após lesão miocárdica, o grupo HFD-HIIT apresentou maior percentual da pressão desenvolvida do ventrículo esquerdo em relação ao basal quando comparado aos demais grupos.Entretanto, a área de infarto do ventrículo esquerdo foi similar entre os grupos.Conclusão:Quatro sessões de exercício físico, seja contínuo ou HIIT, reverteram a atrofia muscular causada pela dieta hiperlipídica. No entanto, somente o protocolo HIIT conferiu cardioproteção aos animais obesos

Submitted by Boris Flegr (boris@uerj.br) on 2021-01-05T18:49:52Z No. of bitstreams: 1 Gabriella de Oliveira Lopes_Dissertacao.pdf: 2471705 bytes, checksum: f4cae6409e485d8e1e2442b79bd592de (MD5) Made available in DSpace on 2021-01-05T18:49:52Z (GMT). No. of bitstreams: 1 Gabriella de Oliveira Lopes_Dissertacao.pdf: 2471705 bytes, checksum: f4cae6409e485d8e1e2442b79bd592de (MD5) Previous issue date: 2019-03-13 Introduction: Studies assessing the vascular function and redox status of people living with HIV in response to exercise training are scarce. Objective: To compare macro- and microvascular endothelial function in physically active vs. inactive HIV-infected patients under antiretroviral therapy. Methods: Using a cross-sectional design, 19 patients with HIV (53.1 ± 6.1 yr) physically active (60 min/session; 3 sessions/wk; moderate intensity) and 25 inactive (51.2 ± 6.3 yr) were compared as for macro- and microvascular reactivity, systemic microvascular density, and oxidative stress. Results: Active patients showed greater increment of forearm blood flow during reactive hyperemia (521.7±241.9 vs. 361.4±125.0 %; P=0.04) and systemic microvascular density (120.8±21.1 vs. 105.6±25.0 capillaries.mm-2; P=0.03) than inactive patients. No significant difference between groups was detected for endothelium-dependent and independent skin microvascular response (P>0.05). As for redox status, carbonyl groups (P=0.22), lipid peroxidation (P=0.86), catalase activity (P=0.99), and nitric oxide levels (P=0.72) were similar across groups. However, superoxide dismutase activity was greater in active vs. inactive HIV (0.118±0.013 vs. 0.111±0.007 UmL-1; P=0.05). Immune function reflected by total T CD4 and T CD8 cells count (cell.mm-3) did not differ between active and inactive groups (P>0.82). Conclusion: Physically active HIV exhibited similar immune function, but greater macrovascular reactivity, systemic microvascular density, and superoxide dismutase activity than inactive patients of similar age. Introdução: São escassos os estudos sobre a função vascular e estado redox de pacientes vivendo com HIV em resposta ao treinamento físico.Objetivo: Comparar a função endotelial micro e macrovascular entre pacientes vivendo com HIV fisicamente ativos e inativos, sob utilização da terapia antirretroviral. Métodos: Através de desenho transversal, 19 pacientes com HIV (53 ± 6 anos) fisicamente ativos (60 min/sessão;3sessões/semana; intensidade moderada) e 25 inativos (51 ± 6 anos) foram comparados quanto a reatividade macro e microvascular, densidade microvascular sistêmica e estresse oxidativo. Resultados: O grupo ativo apresentou maior incremento do fluxo sanguíneo do antebraço durante a hiperemia reativa pós-oclusiva (521,7 ± 241,9 vs. 361,4 ± 125,0%; P = 0,04) e densidade microvascular sistêmica (120,8 ± 21,1 vs. 105,6 ± 25,0 capilares.mm-2; P = 0,03) em relação aos pacientes inativos. Nenhuma diferença significativa entre os grupos foi detectada para a vasodilatação microvascular cutânea endotélio-dependente e independente (P> 0,05). Quanto ao estado redox, grupo carbonila (P = 0,22), peroxidação lipídica (P = 0,86), atividade da catalase (P = 0,99) e níveis de óxido nítrico (P = 0,72) foram similares entre os grupos. No entanto, a atividade da superóxido dismutase foi maior no grupo ativo vs. inativo (0,118 ± 0,013 vs. 0,111 ± 0,007 UmL-1; p = 0,05). A função imune refletida pela contagem total de células T CD4 e T CD8 (cell.mm-3) não diferiu entre os grupos ativo e inativo (P> 0,82). Conclusão: Pacientes com HIV fisicamente ativos exibiram função imunológica similar, mas maior reatividade macrovascular, densidade microvascular sistêmica e atividade da superóxido dismutase em relação a pacientes inativos com idade pareada.

Submitted by Boris Flegr (boris@uerj.br) on 2021-01-05T18:51:02Z No. of bitstreams: 1 Rafael Riera de Farias_Dissertacao.pdf: 1785959 bytes, checksum: ccd1fb5dc6f6c8c5fbdb0a709c701b30 (MD5) Made available in DSpace on 2021-01-05T18:51:02Z (GMT). No. of bitstreams: 1 Rafael Riera de Farias_Dissertacao.pdf: 1785959 bytes, checksum: ccd1fb5dc6f6c8c5fbdb0a709c701b30 (MD5) Previous issue date: 2017-06-29 Ischemic training (IT) has been proposed as a tool to induce muscle hypertrophy, but its safety remains controversial as it may cause mean blood pressure (MBP) increments due to the activation of the muscle metaboreflex (MM). However, IT also causes metabolites accumulation that in turn may desensitise type III and IV nerve endings, which are thought to trigger the MM1. Then, we hypothesised that a period of IT would result in a blunted hemodynamic activation during the MM. In order to evaluate the effect of IT on heart rate (HR), ventricular filling time, systolic volume ratio / left ventricular ejection time, MAP, systolic volume (SV), cardiac output (CO), and peripheral vascular resistance (PVR) to the activation of MM in healthy youngsters. 17 young healthy male (age 21±2 yrs) took part in this study. Hemodynamics during the MM was obtained by the method of the post-exercise muscle ischemia2 at baseline (T0) and after one month (T1) of dynamic IT (handgrip), conducted at 30% of maximum voluntary contraction in the dominant arm with circulatory occlusion, which was obtained with a pressure of 50 mmHg above systolic blood pressure. IT was applied for 3 days/week. Hemodynamic measurements were assessed by means of impedance cardiograph, which has been commonly employed in resting and exercising subjects. The main results were that none of the studied parameters changed in response to MM after IT. In detail, MBP response was +4.09±3.87 vs. +2.23±4.65 mmHg at T0 and T1 respectively (p>0.05). Similarly, there was no difference in HR (-3.47±9.26 vs 0.81±9.96 bpm), SV (+11.3±20.2 vs. +2.28±13.07 mL), CO (+349±1643.4 vs. +57.2±801.9 mL*l-1), SVR (-14.6±201.6 vs. +5.59±104.9 dynes·s-1·cm-5) and VFR ( 5,8 +/- 2,8 vs 9,3+/- 3,3 ml/s). Contrary to initial hypothesis, this investigation provides evidence that a period of 4 weeks of IT is not able to change the hemodynamic response to metaboreflex activation in young healthy male subjects. Thus, the IT protocol employed in the present investigation was not able to desensitise type III and IV nerve endings. Ischemic training (IT) has been proposed as a tool to induce muscle hypertrophy, but its safety remains controversial as it may cause mean blood pressure (MBP) increments due to the activation of the muscle metaboreflex (MM). However, IT also causes metabolites accumulation that in turn may desensitise type III and IV nerve endings, which are thought to trigger the MM1. Then, we hypothesised that a period of IT would result in a blunted hemodynamic activation during the MM. In order to evaluate the effect of IT on heart rate (HR), ventricular filling time, systolic volume ratio / left ventricular ejection time, MAP, systolic volume (SV), cardiac output (CO), and peripheral vascular resistance (PVR) to the activation of MM in healthy youngsters. 17 young healthy male (age 21±2 yrs) took part in this study. Hemodynamics during the MM was obtained by the method of the post-exercise muscle ischemia2 at baseline (T0) and after one month (T1) of dynamic IT (handgrip), conducted at 30% of maximum voluntary contraction in the dominant arm with circulatory occlusion, which was obtained with a pressure of 50 mmHg above systolic blood pressure. IT was applied for 3 days/week. Hemodynamic measurements were assessed by means of impedance cardiograph, which has been commonly employed in resting and exercising subjects. The main results were that none of the studied parameters changed in response to MM after IT. In detail, MBP response was +4.09±3.87 vs. +2.23±4.65 mmHg at T0 and T1 respectively (p>0.05). Similarly, there was no difference in HR (-3.47±9.26 vs 0.81±9.96 bpm), SV (+11.3±20.2 vs. +2.28±13.07 mL), CO (+349±1643.4 vs. +57.2±801.9 mL*l-1), SVR (-14.6±201.6 vs. +5.59±104.9 dynes·s-1·cm-5) and VFR ( 5,8 +/- 2,8 vs 9,3+/- 3,3 ml/s). Contrary to initial hypothesis, this investigation provides evidence that a period of 4 weeks of IT is not able to change the hemodynamic response to metaboreflex activation in young healthy male subjects. Thus, the IT protocol employed in the present investigation was not able to desensitise type III and IV nerve endings.

Submitted by Boris Flegr (boris@uerj.br) on 2021-01-05T18:14:07Z No. of bitstreams: 1 Claudia Dissertacao FINAL140617.pdf: 2997330 bytes, checksum: 9ade6cd6a3afcfb7b8d62abf493490ac (MD5) Made available in DSpace on 2021-01-05T18:14:07Z (GMT). No. of bitstreams: 1 Claudia Dissertacao FINAL140617.pdf: 2997330 bytes, checksum: 9ade6cd6a3afcfb7b8d62abf493490ac (MD5) Previous issue date: 2017-02-16 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Doxorubicin (DOX) is an effective chemotherapeutic in the regression of various neoplasms, but its clinical use is limited by cardiotoxicity. Among the existing strategies to attenuate the toxic effect of the drug, physical activity has been recognized as cardioprotective; however, this relationship has not been studied. In this context, the present study was based on the hypothesis that the beneficial effect of exercise can be mediated through nitric oxide (NO), an essential inorganic gas for cardiovascular homeostasis. For this, we investigated the effects of aerobic training on the structure of cardiac tissue, synthesis of NO and biomarkers of oxidative stress in the heart of rats Sprague Dawley with heart failure induced by DOX. The effects of the exercise were also evaluated in the concomitant presence of DOX and NG-nitro-L-arginina-metil-ester (L-NAME), which inhibits NO production. Thus, the following groups were formed: (1) control (CONT); (2) DOX + exercise (DOX / EX); (3) DOX + sedentary (DOX / SED); (4) L-NAME + sedentary (L-NAME / SED); (5) DOX + L-NAME + exercise (DOX / L-NAME / EXE); And (6) DOX + L-NAME + sedentary (DOX / L-NAME / SED). The administration of doxorubicin led to a reduction in the expression of the neuronal and inducible isoforms of NO synthase (NOS), responsible for the synthesis of NO. The exercise, however, was able to reverse this change, since there was no difference between the DOX / EXE and control groups. In the evaluation of oxidative damage of lipids and proteins, no differences were observed between the groups. In relation to the activity of antioxidant enzymes, it was observed that the exercise was able to increase the activity of superoxide dismutase and catalase in animals with heart failure in relation to the DOX / SED group; and the restoration of catalase activity was not observed in the DOX / L-NAME / EXE group. The antioxidant enzyme glutathione peroxidase showed the opposite result, since its activity was higher in the DOX / SED group in relation to the others. Regarding the analysis of the cardiac structure, no hypertrophy was observed in any of the groups, on the other hand, the animals of the DOX / SED group showed an increase in interstitial fibrosis compared to controls and exercised animals that received DOX, but did not differ in relation to the group DOX / L-NAME / EXE. The results demonstrate that aerobic physical activity was effective in attenuating the damage caused by DOX to cardiac tissue, since there was an improvement in the profile of antioxidant enzymes, fibrosis, elevation of NOS, reduction of blood pressure, and a longer survival. Such benefits were not observed when exercise was associated with administration of L-NAME, which demonstrates a possible contribution of NO to the observed cardioprotection. A doxorrubicina (DOX) é um quimioterápico eficaz na regressão de várias neoplasias, porém seu uso clínico é limitado pela cardiotoxicidade. Entre as estratégias existentes para amenizar o efeito tóxico do fármaco, a atividade física tem sido reconhecida como cardioprotetora, entretanto, essa relação ainda foi pouco estudada. Neste contexto, o presente estudo se baseou na hipótese de que o efeito benéfico do exercício possa ser mediado através do óxido nítrico (NO), um gás inorgânico essencial para homeostase cardiovascular. Para isso, foram investigados os efeitos do treinamento aeróbio sobre a estrutura do tecido cardíaco, síntese de NO e biomarcadores de estresse oxidativo no coração de ratas Sprague Dawley com insuficiência cardíaca induzida por DOX. Os efeitos do exercício também foram avaliados na presença concomitante de DOX e NG-nitro-L-arginina-metil-éster (L-NAME), a qual inibe a produção de NO. Dessa forma, os seguintes grupos foram formados: (1) controle (CONT); (2) DOX + exercício (DOX/EX); (3) DOX+sedentário (DOX/SED); (4) L-NAME + sedentário (L-NAME/SED); (5) DOX+L-NAME + exercício (DOX/L-NAME/EXE); e (6) DOX + L-NAME + sedentário (DOX/L-NAME/SED). A administração de doxorrubicina levou a uma redução na expressão das isoformas neuronal e induzível da NO sintase (NOS), responsáveis pela síntese de NO. O exercício, no entanto, foi capaz de reverter essa alteração, uma vez que não houve diferença entre os grupos DOX/EXE e controle. Na avaliação do dano oxidativo de lipídios e proteínas, não foram observadas diferenças entre os grupos. Em relação à atividade das enzimas antioxidantes, foi observado que o exercício foi capaz de aumentar a atividade da superóxido dismutase e catalase nos animais com insuficiência cardíaca em relação ao grupo DOX/SED; sendo que a restauração da atividade da catalase não foi observada no grupo DOX/L-NAME/EXE. A enzima antioxidante glutationa peroxidase exibiu resultado oposto, já que sua atividade foi maior no grupo DOX/SED em relação aos demais. Quanto à análise da estrutura cardíaca, não foi observado hipertrofia em nenhum dos grupos, por outro lado, os animais do grupo DOX/SED apresentaram aumento da fibrose intersticial comparado aos controles e aos animais exercitados que receberam DOX, mas não diferiram em relação ao grupo DOX/L-NAME/EXE. Os resultados demonstram que a atividade física aeróbica foi eficaz em atenuar os danos causados pela DOX ao tecido cardíaco, uma vez que houve melhora do perfil de enzimas antioxidantes, da fibrose, elevação da NOS, redução da pressão arterial, além de maior sobrevida. Tais benefícios não foram observados quando o exercício foi associado à administração de L-NAME, o que demonstra uma possível contribuição do NO na cardioproteção observada.