Vascular dysfunction in obesity: beneficial effects of aerobic exercise training in animal models

Abstract Cardiovascular disease (CVD) is the leading cause of mortality in the world and several risk factors for developing CVD have been pointed out, including obesity and physical inactivity. Endothelial dysfunction as a consequence of metabolic and inflammatory disorders plays an important role in the onset of vascular complications in obesity. In addition, it is well established that aerobic exercises promote beneficial effects on CVD by increasing nitric oxide (NO) production or its bioavailability in human and experimental models. The interest in exercise studies increased significantly, with promising results. Considering the importance of this field, the purpose of this mini-review is to summarize the animal studies that investigated the physiological mechanisms of vascular dysfunction in obesity and how aerobic exercise training influenced these alterations.(AU)

Resistance exercise improves metabolic parameters and changes adipocyte-derived leptin: a comparison between genders in untrained adults

This study examined gender differences after resistance exercise (RE) by measuring fasting plasma levels of creatine kinase, lipid profile, blood glucose, adiponectin, tumor necrosis factor alpha (TNF-α), and leptin. Thirteen women (23.6 ± 7.3 years) and 11 men (29.5 ± 9 years) were enrolled in the study. Two bouts of RE were performed on two different occasions separated by 48 h each. Blood samples were collected and analyzed at baseline and 15 h after the last RE session. Increased creatine kinase levels and improvements in lipid profile and blood glucose were found for both genders. No changes in adiponectin and TNF-α levels were observed for both genders, but leptin levels were reduced (p < 0.05) only for women after RE. Collectively, our findings clearly show that RE was effective in lowering blood glucose and that this effect was not accompanied by changes in adiponectin levels in healthy subjects, indicating that RE is still an important tool for the prevention of metabolic diseases. Furthermore, two sessions of RE promoted a reduction in leptin levels in women, even though no changes in body weight were found, showing that RE is an interesting approach to study obese patients and metabolic regulation

Assessment of endothelial function by flow-mediated dilation in diabetic patients: effects of physical exercise

The endothelium is now recognized as an endocrine organ that acts to maintain vascular homeostasis regulating the vascular tone and structure. The endothelial cells synthetize a variety of mediators among them, the main agent is the nitric oxide (NO), a potent vasodilator. NO exerts its protective role preventing leukocyte adhesion and migration, expression of adhesion molecules, platelet aggregation, cell proliferation, and promoting the relaxation of smooth muscle cells. On the other hand, endothelial dysfunction present in many chronic diseases such as atherosclerosis, coronary artery disease, peripheral artery disease, hypertension and diabetes mellitus, is characterized by reduced NO bioavailability. Thus, a few decades ago, measurement of endothelial function has emerged as valuable tool that provides insights in the pathophysiological mechanisms, opportunity to identify early disease and cardiovascular risk, preventing future events or avoiding the progression of the disease. Diabetic patients, particularly, have been a target to apply this technique, mainly because this condition has been related with an impairment of endothelium-dependent dilation and it is believed that the endothelium dysfunction is the basis of diabetes complications such as coronary artery disease and accelerated atherosclerosis. In addition, cardiovascular complications represent the leading cause of morbidity and death in diabetes mellitus. Besides pharmacological therapy, lifestyle modifications have been recommended by specific organizations as a strategy to improve the endothelial function or even prevent the development of diabetes. The aim of this mini eview is to give an update about the importance of endothelium, most common non-invasive technique to evaluate its function, and to summarize some mechanisms involved in endothelial dysfunction and the beneficial effects of exercise in diabetes mellitus.

Interação entre as vias de sinalização de receptores serotoninérgicos e Β-adrenérgicos em artéria femoral de ratos / Interaction between serotoninergic-and β-adrenergic receptors signaling pathways in rat femoral artery / Interacción entre las vías de señalización de receptores serotoninérgicos y β-adrenégicos en la arteria femoral de ratones

FUNDAMENTO: A doença coronária tem sido amplamente estudada em pesquisas cardiovasculares. No entanto, pacientes com doença arterial periférica (DAP) têm piores resultados em comparação àqueles com doença arterial coronariana. Portanto, os estudos farmacológicos com artéria femoral são altamente relevantes para a melhor compreensão das respostas clínicas e fisiopatológicas da DAP. OBJETIVO: Avaliar as propriedades farmacológicas dos agentes contráteis e relaxantes na artéria femoral de ratos. MÉTODOS: As curvas de resposta de concentração à fenilefrina contrátil (FC) e à serotonina (5-HT) e os agentes relaxantes isoproterenol (ISO) e forskolina foram obtidos na artéria femoral de ratos isolada. Para as respostas ao relaxamento, os tecidos foram contraídos com FC ou 5-HT. RESULTADOS: A potência de classificação na artéria femoral foi de 5-HT > FC para as respostas contráteis. Em tecidos contraídos com 5-HT, as respostas de relaxamento ao isoproterenol foram praticamente abolidas em comparação aos tecidos contraídos com FC. A forskolina, um estimulante da adenilil ciclase, restaurou parcialmente a resposta de relaxamento ao ISO em tecidos contraídos com 5-HT. CONCLUSÃO: Ocorre uma interação entre as vias de sinalização dos receptores β-adrenérgicos e serotoninérgicos na artéria femoral. Além disso, esta pesquisa fornece um novo modelo para estudar as vias de sinalização serotoninérgicas em condições normais e patológicas que podem ajudar a compreender os resultados clínicos na DAP.

BACKGROUND: Coronary heart disease has been widely studied in cardiovascular research. However, patients with peripheral artery disease (PAD) have worst outcomes compared to those with coronary artery disease. Therefore, pharmacological studies using femoral artery are highly relevant for a better understanding of the pathophysiologic responses of the PAD. OBJECTIVE: The aim of this study was to evaluate the pharmacologic properties of the contractile and relaxing agents in rat femoral artery. METHODS: Concentration response curves to the contractile phenylephrine (PE) and serotonin (5-HT) and the relaxing agents isoproterenol (ISO) and forskolin were obtained in isolated rat femoral artery. For relaxing responses, tissues were precontracted with PE or 5-HT. RESULTS: The order rank potency in femoral artery was 5-HT > PE for contractile responses. In tissues precontracted with 5-HT, relaxing responses to isoproterenol was virtually abolished as compared to PE-contracted tissues. Forskolin, a stimulant of adenylyl cyclase, partially restored the relaxing response to ISO in 5-HT-precontracted tissues. CONCLUSION: An interaction between β-adrenergic- and serotoninergic- receptors signaling pathway occurs in femoral artery. Moreover, this study provides a new model to study serotoninergic signaling pathway under normal and pathological conditions which can help understanding clinical outcomes in the PAD.

FUNDAMENTO: La enfermedad coronaria ha sido ampliamente estudiada en las investigaciones cardiovasculares. Sin embargo, los pacientes con enfermedad arterial periférica (EAP), tienen los peores resultados en comparación con aquellos con la enfermedad arterial coronaria. Por tanto, los estudios farmacológicos con la arteria femoral son extremadamente importantes para obtener una mejor comprensión de las respuestas clínicas y fisiopatológicas de la EAP. OBJETIVO: Evaluar las propiedades farmacológicas de los agentes contráctiles y relajantes en la arteria femoral de los ratones. MÉTODOS: Las curvas de concentración-respuesta a los agentes conctráctiles fenilefrina (FE) y a la serotonina (5-HT) y los agentes relajantes isoproterenol (ISO) y forskolina, se obtuvieron en la arteria femoral de ratones ya aislada. Para las respuestas a la relajación, los tejidos fueron contraídos con FE o 5-HT. RESULTADOS: La potencia de clasificación en la arteria femoral fue de 5-HT > FE para las respuestas contráctiles. En los tejidos contraídos con 5-HT, las respuestas de relajación al isoproterenol fueron prácticamente eliminadas en comparación con los tejidos contraídos con FE. La forskolina, un estimulante de la adenilil ciclasa, restauró parcialmente la respuesta de relajación al ISO en los tejidos contraídos con 5-HT. CONCLUSIÓN: Ocurre una interacción entre las vías de señalización de los receptores β-adrenérgicos y serotoninérgicos en la arteria femoral. Además, esa investigación suministra un nuevo modelo para estudiar las vías de señalización serotoninérgicas en condiciones normales y patológicas que puedan ayudar a comprender los resultados clínicos en la EAP.

Papel do exercício físico na isquemia/reperfusão pulmonar e resposta inflamatória: [revisão] / Role of exercise training on pulmonary ischemia/reperfusion and inflammatory response: [review]

O avanço tecnológico associado aos novos conhecimentos científicos tem proporcionado melhora na prevenção e/ou tratamento das complicações cardiorrespiratórias advindas de cirurgias cardiotorácicas e procedimentos envolvendo isquemia/reperfusão (IR), mas os riscos destes procedimentos ainda permanecem altos. Assim, medidas profiláticas que possam reduzir o aparecimento das complicações pós-cirúrgicas em pacientes devem ser investigadas. O exercício físico aeróbio de moderada intensidade tem sido recomendado como terapia não farmacológica tanto na prevenção como no tratamento de diversas doenças cardiovasculares e endócrino-metabólicas. Assim, o objetivo desse trabalho foi realizar uma revisão de literatura sobre os mecanismos pelos quais o processo de IR pulmonar promove lesão local e sistêmica de órgãos, e o papel dos mediadores inflamatórios na IR pulmonar. Além disso, essa revisão abordará a influência do exercício físico moderado como abordagem profilática nas complicações advindas da IR pulmonar. Essa revisão evidencia a escassez de trabalhos na área e a necessidade de maiores estudos enfocando o preparo físico dos pacientes a serem submetidos à cirurgia cardiotorácica. Trabalhos pioneiros foram desenvolvidos em modelos animais, demonstrando a importância do exercício físico na redução da resposta inflamatória induzida pelo procedimento de IR pulmonar. Conclui-se que o preparo pré-cirúrgico dos pacientes deve envolver equipe multidisciplinar da área de saúde, com inclusão de profissional de educação física, para que a prescrição do exercício físico seja individualizada e supervisionada. Além disso, esse preparo pré-cirúrgico poderá propiciar redução das complicações advindas do processo operatório, redução do período de internação hospitalar e, consequentemente, melhora na recuperação do paciente, acarretando ainda menores gastos para o sistema de saúde. Foram utilizadas como referências publicações em inglês e português de artigos...

Advances in new technologies associated with improvement of knowledge in medicine have promoted important development in therapeutic and preventive approaches in an attempt to diminish complications following cardiothoracic process involving ischemia/ reperfusion (IR). Nevertheless, postoperative pulmonary injuries remain high and are considered one of the most frequent complications after cardiothoracic surgery. Thus, new strategies with prophylactic actions are crucial in cardiovascular area in an attempt to reduce complications and to improve patient life. It is well documented that exercise training is a non-pharmacological tool to prevent and/or treat cardiovascular and endocrine-metabolic diseases. The aim of this review was to provide an update of several studies pulmonary IR process and its local and systemic complications and the role of inflammatory response. Furthermore, this review focused on the effects of exercise training on the pulmonary IR as an important strategy to diminish its complications. This review shows that few studies exist regarding the health-promoting physical exercise in cardiothoracic surgery and how important is necessary to increase studies in this area. Recently, studies from our laboratory showed beneficial effects of exercise training in experimental model of pulmonary IR. Collectively, data show that physical preconditioning for patients is very important approach to reduce postsurgical complications as well as diminish the time of hospitalization which includes a specialized personal trainer in the health team. Moreover, this preventive strategy might improve patient recovery and would lead to consuming less resources of the health care system. This review included experimental studies in English and Portuguese found in SciELO and MEDLINE (from 1987 to 2008) and also classics texts related to the title.