Cardiovascular autonomic dysfunction and oxidative stress induced by fructose overload in an experimental model of hypertension and menopause

Background: Metabolic syndrome is characterized by the association of 3 or more risk factors, including: abdominal obesity associated with an excess of abdominal fat, insulin resistance, type 2 diabetes, dyslipidemia and hypertension. Moreover, the prevalence of hypertension and metabolic dysfunctions sharply increases after the menopause. However, the mechanisms involved in these changes are not well understood. Thus, the aim of this study was to assess the effects of fructose overload on cardiovascular autonomic modulation, inflammation and cardiac oxidative stress in an experimental model of hypertension and menopause. Methods: Female SHR rats were divided into (n = 8/group): hypertensive (H), hypertensive ovariectomized (HO) and hypertensive ovariectomized undergoing fructose overload (100 g/L in drinking water) (FHO). Arterial pressure (AP) signals were directly recorded. Cardiac autonomic modulation was evaluated by spectral analysis. Oxidative stress was evaluated in cardiac tissue. Results: AP was higher in the FHO group when compared to the other groups. Fructose overload promoted an increase in body and fat weight, triglyceride concentration and a reduction in insulin sensitivity. IL-10 was reduced in the FHO group when compared to the H group. TNF-α was higher in the FHO when compared to all other groups. Lipoperoxidation was higher and glutathione redox balance was reduced in the FHO group when compared to other groups, an indication of increased oxidative stress. A negative correlation was found between IL-10 and adipose tissue. Conclusion: Fructose overload promoted an impairment in cardiac autonomic modulation associated with inflammation and oxidative stress in hypertensive rats undergoing ovarian hormone deprivation.Fil: Conti, Filipe Fernandes. Universidad Nove de Julho; BrasilFil: Brito, Janaina de Oliveira. Universidad Nove de Julho; BrasilFil: Bernardes, Nathalia. Universidade de Sao Paulo; BrasilFil: Dias, Danielle da Silva. Universidad Nove de Julho; BrasilFil: Sanches, Iris Callado. Universidad Nove de Julho; BrasilFil: Malfitano, Christiane. Universidad Nove de Julho; BrasilFil: Llesuy, Susana Francisca. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Química Analítica y Fisicoquímica; ArgentinaFil: Irigoyen, Maria-Claudia. Universidade de Sao Paulo; BrasilFil: De Angelis, Kátia. Universidad Nove de Julho; Brasi

Simvastatin-induced cardiac autonomic control improvement in fructose-fed female rats

OBJECTIVE: Because autonomic dysfunction has been found to lead to cardiometabolic disorders and because studies have reported that simvastatin treatment has neuroprotective effects, the objective of the present study was to investigate the effects of simvastatin treatment on cardiovascular and autonomic changes in fructose-fed female rats. METHODS: Female Wistar rats were divided into three groups: controls (n=8), fructose (n=8), and fructose+ simvastatin (n=8). Fructose overload was induced by supplementing the drinking water with fructose (100 mg/L, 18 wks). Simvastatin treatment (5 mg/kg/day for 2 wks) was performed by gavage. The arterial pressure was recorded using a data acquisition system. Autonomic control was evaluated by pharmacological blockade. RESULTS: Fructose overload induced an increase in the fasting blood glucose and triglyceride levels and insulin resistance. The constant rate of glucose disappearance during the insulin intolerance test was reduced in the fructose group (3.4+ 0.32%/min) relative to that in the control group (4.4+ 0.29%/min). Fructose+simvastatin rats exhibited increased insulin sensitivity (5.4+0.66%/min). The fructose and fructose+simvastatin groups demonstrated an increase in the mean arterial pressure compared with controls rats (fructose: 124+2 mmHg and fructose+simvastatin: 126 + 3 mmHg vs. controls: 112 + 2 mmHg). The sympathetic effect was enhanced in the fructose group (73 + 7 bpm) compared with that in the control (48 + 7 bpm) and fructose+simvastatin groups (31+8 bpm). The vagal effect was increased in fructose+simvastatin animals (84 + 7 bpm) compared with that in control (49 + 9 bpm) and fructose animals (46+5 bpm). CONCLUSION: Simvastatin treatment improved insulin sensitivity and cardiac autonomic control in an experimental model of metabolic syndrome in female rats. These effects were independent of the improvements in the classical plasma lipid profile and of reductions in arterial pressure. These results support the hypothesis that statins reduce the cardiometabolic risk in females with metabolic syndrome

Exercise Physiology for undergraduates: the use of teaching strategies basead on the dialectical method

A metodologia dialética propõe um ensino de dupla mão (professor-aluno) que provoque a aprendizagem por meio de tarefas contínuas dos sujeitos. Para isso, o professor assume o papel de mediador e dirige as diferentes atividades. Nesse contexto, a Fisiologia do Exercício é uma disciplina academicamente orientada que está inserida em um ambiente dinâmico, e a utilização de estratégias de ensino se faz necessária para otimizar a apropriação do conhecimento de forma ativa, além de contribuir para a maior autonomia dos estudantes universitários. Portanto, o objetivo do presente estudo foi o de utilizar diferentes estratégias de ensinagem por meio de atividades propostas aos alunos na disciplina de Fisiologia da Atividade Motora I da Escola de Educação Física e Esporte da Universidade de São Paulo e correlacionar o desempenho do aluno com a sua participação nessas atividades propostas. Nossos principais achados demonstram correlações significativas e positivas entre a presença nas aulas e o desempenho nas avaliações (p < 0,0001; r = 0,84), bem como entre a realização das atividades propostas e o desempenho nas avaliações (p < 0,0001; r = 0,69). Em conjunto, esses dados sugerem que a utilização de diferentes estratégias de ensinagem baseadas na metodologia dialética com a ativa participação dos alunos é essencial para um bom rendimento acadêmico, sendo altamente recomendada para o ensino da Fisiologia do Exercício.The dialectic method proposes a two-way teaching (teacher-student) that causes learning through ongoing task of the subjects. For this, the teacher assumes the role of mediator and directs several activities. In line with the above, Exercise Physiology is an academically oriented discipline undergoing in a dynamic environment, and the use of different teaching strategies is needed to optimize the appropriation of knowledge in an active way and contribute to the greater autonomy of university students. Therefore, the aim of this study was apply different strategies in the course entitled "Physiology of the Motor Activity I" at School of Physical Education and Sport of University of Sao Paulo and assess a correlation between students participation and students performance. We used teaching strategies such as exposition and dialogue classes, practical classes, conversations with experts, directed study, study of scientific texts, concept mapping, case study and study of the environment in order to optimize the appropriation of the concepts of exercise physiology with emphasis on neuromuscular and cardiovascular physiology exercise. Our main findings show significant and positive correlations between the presence in classes and the performance evaluations (p < 0.0001, r = 0.84) as well as between the tasks proposed and the performance evaluations (p < 0.0001; r = 0.69). Altogether, these data suggest that using different teaching strategies based on the dialectic method associated with the participation of students is essential for a good academic performance in Exercise Physiology

Combined Aerobic and Resistance Exercise Training Improve Hypertension Associated With Menopause

The prevalence of hypertension sharply increases in menopausal women. Recent studies have demonstrated that aerobic or resistance training may help control hypertension. In this study, we report that combining aerobic and resistance training may provide an effective therapeutic approach for hypertension control, attenuating inflammation and oxidative stress in ovariectomized rats. Female Wistar and spontaneous hypertensive rats (SHR) were distributed into four groups: sedentary control (C), sedentary hypertensive (HR), sedentary hypertensive ovariectomized (HR-O), and combined trained hypertensive ovariectomized (T-HR-O). Combined exercise training was performed on a motor treadmill (aerobic training) and on a ladder adapted to rats (resistance training), in alternate days for 8 weeks. Direct arterial pressure was recorded and oxidative stress and inflammation were evaluated in cardiac and renal tissue. Ovariectomy increases increased mean arterial blood pressure, sympathetic modulation, and oxidative stress in SHR. Combining aerobic and resistance training reduced mean arterial blood pressure (12% vs. HR-O), heart rate (8% vs. HR-O), vascular sympathetic modulation (40% vs. HR-O), and improved baroreflex sensitivity. Combined training reduced cardiac inflammation (TNF and IL-6) and cardiac and renal lipoperoxidation (59% and 57%, respectively vs. HR-O). It also enhanced cardiac (71%) and renal (76%) total antioxidant capacity when compared to HR-O group. In conclusion, combining aerobic and resistance training improves mean arterial blood pressure, cardiovascular autonomic control, preventing cardiac and renal oxidative stress and inflammation in an experimental hypertension model with surgical menopause induced with ovariectomy

PROGRAMA DE PÓS-GRADUAÇÃO EM CIÊNCIAS DO ENVELHECIMENTO DA UNIVERSIDADE SÃO JUDAS TADEU: TRAJETÓRIA E PANORAMA ATUAL

O Programa de Pós-Graduação em Ciências do Envelhecimento (PGCE), nível mestrado, foi aprovado pela CAPES em 2009 e iniciou suas atividades em 2010. É o único programa de pós-graduação de uma universidade privada com foco em Gerontologia na cidade de São Paulo. Atualmente, o PGCE está organizado em uma área de concentração denominada Ciências do Envelhecimento e em três linhas de pesquisa: (1) Aspectos educacionais, psicológicos e socioculturais do envelhecimento; (2) Doenças associadas ao envelhecimento; e (3) Saúde e funcionalidade no envelhecimento. Esta revisão narrativa apresenta a descrição dos atuais projetos de pesquisa do PGCE, conforme apresentado no relatório para avaliação de 2017 a 2020, recentemente submetido à CAPES. No período acima referido, a produção científica do PGCE correspondeu a 331 produções: 54 artigos em periódicos, 15 capítulos de livros, 36 trabalhos em anais de congressos, 91 apresentações de trabalhos em congressos e 135 produções técnicas. Ao longo de sua trajetória, algumas mudanças destacaram as características interdisciplinares do PGCE, o que pode ser evidenciado pelo aumento: na qualidade dos artigos publicados, no número de alunos matriculados, de dissertações apresentadas e de projetos de pesquisa e extensão desenvolvidos no período de 2017 a 2020, em comparação com o período de 2013 a 2016. O PGCE é um programa dinâmico que se adapta às necessidades emergentes da sociedade, integra pesquisa e extensão e, ao mesmo tempo, apresenta uma produção robusta para a comunidade científica

Cardiovascular control in female diabetic ovariectomized rats: effects of dynamic aerobic, resistance and combined exercise training

O treinamento físico aeróbico induz atenuação de disfunções cardiometabólicas que acometem mulheres menopausadas e/ou diabéticas. Entretanto, estudos envolvendo treinamento resitido ou combinado (aeróbio + resistido) são escassos e controversos. Dessa forma, os objetivos do presente estudo foram avaliar os efeitos metabólicos, cardiovasculares e autonômicos da privação dos hormônios ovarianos na presença ou não de diabetes induzido por estreptozotocina em ratas, bem os efeitos do treinamento físico aeróbio dinâmico, resistido dinâmico, ou combinado nesta condição. Ratas Wistar (200-220g) foram dividas em um grupo controle sedentário (ES), um grupo diabético sedentário (DS) e 5 grupos ooforectomizados (retirada bilateral dos ovários) (n=8), sendo um euglicêmico sedentário (EOS) e os demais diabéticos (estreptozotocina, 50 mg/kg, iv): sedentário (DOS), submetido a treinamento físico (TF) aeróbio em esteira (DOTA), a TF resistido em escada (DOTR), ou a TF combinado, em escada e esteira em dias alternados (DOTC). Após as 8 semanas de TF, a função e a morfometria cardíaca foram avaliadas pelo ecocardiograma e, no dia seguinte, os animais foram canulados para registro da pressão arterial (PA) e avaliação da sensibilidade barorreflexa (SB). A análise da variabilidade da frequência cardíaca (FC) e da PA sistólica (PAS) foi realizada no domínio do tempo e da frequência. Os resultados demonstraram aumento de 9% no peso corporal e 10% na PA, e redução de SB (21% nas respostas taquicárdicas) no grupo EOS. Os animais diabéticos apresentaram redução de 19% no peso corporal e na capacidade física (22% no teste máximo em esteira e 19% na carga máxima na escada); redução de 8% na massa e 18% na espessura relativa da parede do ventrículo esquerdo (VE), aumento de 11% na cavidade do VE, de 31% no tempo de relaxamento isovolumétrico e 34% no índice de desempenho miocárdico; além de redução de na PA, na FC, na SB e na banda AF-IP. A associação de diabetes com ooforectomia induziu exacerbação de algumas disfunções, como aumento de 9% na glicemia e de 20% no índice de desempenho miocárdico (IDM); redução de 14% na velocidade de encurtamento do VE e 14% na FC (DOS vs. DS). O treinamento induziu aumento de 77% na capacidade de corrida no grupo DOTA, aumento de 60% na carga máxima no DOTR, e aumento em ambos os parâmetros no DOTC (75% na corrida e 58% na carga máxima). Todos os animais treinados apresentaram reversão da hipotensão e da bradicardia de repouso, associadas a aumento na VAR-IP (DOTA: 79%, DOTR: 79%, DOTC: 65%), normalização da banda de BF-IP, e redução no índice de desempenho miocárdico (DOTA: 16%, DOTR: 15%, DOTC: 31%) (vs. DOS). Os grupos DOTA e DOTC (mas não o DOTR) apresentaram maior SB (respostas taquicárdicas e bradicárdicas), atenuação das alterações morfométricas do VE, e na variabilidade da PA sistólica (vs. DOS). Além disso, o grupo DOTR apresentou aumento de 14% na massa, e redução de 14% na velocidade de encurtamento do VE e de 15% no IDM em relação ao grupo DOS. O grupo DOTC demonstrou redução adicional de 18% no IDM e em relação ao DOTA. A mortalidade foi maior no grupo DOS em comparação aos grupos treinados. Concluindo, os resultados evidenciam que o treinamento físico dinâmico aeróbio, resistido ou combinado induziu benefícios na capacidade física, cardíacos, hemodinâmicos e autonômicos após a privação dos hormônios ovarianos em ratas diabéticas. No entanto, o treinamento físico combinado promoveu efeitos adicionais em relação aos treinamentos aeróbio ou ao resistido nesta condição.Aerobic exercise training induces attenuation of cardiometabolic disorders that affect postmenopausal and/or diabetic women. However, there few and controversial studies involving resistance or combined training (aerobic + resistance) in these conditions. Thus, the objectives of this study were to evaluate the metabolic, cardiac, hemodynamic and autonomic effects of ovarian hormones deprivation in the healthy and streptozotocin-induced diabetic rats, as well as the effects of dynamic aerobic, resistance or combined exercise training in this condition. Female Wistar rats (200-220g) were divided into (n = 8 each group) a sedentary control group (ES), a sedentary diabetic group (SD) and 5 ovariectomized groups (bilateral ovaries removal): sedentary euglycemic (EOS), sedentary diabetic (DOS), trained diabetic by an aerobic protocol on a treadmill (DOTA), by a resistance protocol in ladder (DOTR), or by a combined protocol in ladder+treadmill on alternate days (DOTC). After 8 weeks of training, cardiac morphometric and function were evaluated by echocardiography. On the next day, the animals were cannulated to arterial pressure (AP) recording and baroreflex sensitivity (BS) evaluation. Heart rate (HR) and systolic AP variability were analyzed in the time and frequency domains. The results showed increased of 9% in body weight and 10% in AP, and BS (21% in tachycardic responses) reduction in the EOS group. Diabetic animals showed a reduction of 19% in body weight and in physical capacity (22% in the maximal test on a treadmill and 19% in the maximum load on the ladder), reduction of 8% in mass and of 18% in relative wall thickness of the left ventricle (LV), increase of 11% in LV cavity, 31% in the isovolumetric relaxation time and 34% in myocardial performance index (MPI); in addition to reduction in AP, in HR, BS, and in PI-HF band. The association of diabetes with ovariectomy induced exacerbation of some dysfunctions, such as increased of 9% in blood glucose and 20% in MPI, reduction of 14% in the LV velocity of shortening and 14% in HR (DOS vs. DS). Exercise training induced an increase of 77% in the run capacity in the DOTA group, 60% in the maximum load in DOTR group, and increases in both parameters in DOTC (75% in run and 58% in the maximum load). All trained animals showed reversal of hypotension and bradycardia at rest DOTA: 79%, DOTR: 79%, DOTC: 65%), associated with increased HR variance and normalization of the LF band of pulse interval (PI), and reduced MPI (DOTA: 16%, DOTR: 15%, DOTC: 31%) (vs. DOS). The DOTA and DOTC groups (but not DOTR) had higher BS (tachycardic and bradycardic responses), and attenuation in the LV morphometric changes and in SAP variability (vs. DOS). Furthermore, the DOTR group showed an increase of 14% in mass and a reduction of 14% in LV velocity of shortening and of 15% in MPI in relation to DOS group. The DOTC group showed additional reduction of 18% in MPI and in relation to DOTA. Mortality was higher in DOS group when compared to trained group. In conclusion, the results showed that dynamic aerobic, resistance or combined exercise training induced benefits in physical capacity, cardiac, hemodynamic and autonomic parameters after ovarian hormone deprivation in diabetic rats. However, the combined exercise training promoted additional effects than aerobic or resistance training in this condition

Exercise training associated with estrogen therapy induced cardiovascular benefits after ovarian hormones deprivation

Menopause is recognized as a period of increased risk for coronary heart disease. Although the benefits of exercise training in lowering cardiovascular risk factors are well established, the risks and benefits of hormone therapy have been questioned. The purpose of the present study was to investigate the effects of estrogen therapy (HT) associated or not with exercise training (ET) in autonomic cardiovascular control in ovariectomized (OVX) rats. Female rats were divided into: control, OVX, OVX+HT, OVX+ET and OVX+HT+ET. HT was performed using a 0.25 mg 8-weeks sustained release pellet. Trained groups were submitted to an 8-week exercise training protocol on treadmill. Baroreflex sensitivity (BRS) was evaluated by heart rate responses to arterial pressure (AP) changes, and vagal and sympathetic tonus by pharmacological blockade. Ovariectomy induced an AP increase (123 +/- 2 mmHg vs. 108 +/- 2 mmHg), BRS impairment (similar to 69%), sympathetic activation (similar to 100%) and vagal tonus reduction (similar to 77%) compared to controls. HT or ET normalized the changes in parasympathetic tonus. However, only the association HT + ET was able to promote normalization of AP, BRS and sympathetic tonus, as compared to controls. These results indicate that ET induces cardiovascular and autonomic benefits in OVX rats under HT, suggesting a positive role of this association in the management of cardiovascular risk factor in postmenopausal women. (C) 2009 Elsevier Ireland Ltd. All rights reserved.FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao Paulo[07/57595-5]FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao Paulo[09/06865-8]Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Conselho Nacional de Desenvolvimento Cientifico a Tecnologico (CNPq

Acute exercise adjustments of cardiovascular autonomic control in diabetic rats

Introduction: We evaluated the role of cardiovascular autonomic changes in hemodynamics at rest and in response to exercise in streptozotocin-induced diabetic rats. Methods: Male Wistar rats were divided into nondiabetic (ND, n = 8) and diabetic (D, n = 8) groups. Arterial pressure signals were recorded in the basal state and after atropine or propranolol injections at rest, during exercise and during recovery. Results: At rest, vagal tonus was reduced in D (37 +/- 3 bpm) in comparison with the ND group (61 +/- 9 bpm). Heart rate during exercise was lower in D in relation to ND rats associated with reduced vagal withdrawal in the D group. The D rats had an increase in vagal tonus in the recovery period (49 +/- 6 bpm). Conclusions: Exercise-induced hemodynamic adjustment impairment in diabetic rats was associated with reduced cardiac vagal control. The vagal dysfunction was attenuated after aerobic exercise, reinforcing the positive role of this approach in the management of cardiovascular risk in diabetics. Muscle Nerve 46: 96101, 2012Fundacao de Amparo a Pesquisa do Estado de Sao Paulo [FAPESP- 01/00009-0, 07/57595-5, 07/58942-0]Fundacao de Amparo a Pesquisa do Estado de Sao PauloConselho Nacional de Pesquisa e DesenvolvimentoConselho Nacional de Pesquisa e Desenvolvimento [CNPq - 482520/2009-4, 306011/2010-7, 563961/2010-4]Fundacao E.J. ZerbiniFundacao E.J. ZerbiniCNPqCNP