RESUMO
Oxidative stress (OS) occurs when the antioxidant defense system is overwhelmed by the predominance of reactive oxygen species (ROS) and pro-oxidant factors. Several diseases such as hypertension, insulin resistance, type 2 diabetes mellitus and neurodegenerative diseases are characterized by chronic OS. Physical exercise constitutes an affordable tool to prevent or ameliorate these conditions. However, during physical activity, acute ROS are produced inducing an activation in peroxisome proliferator activated receptor-Gamma Coactivator-1alpha (PGC-1α), and nuclear factor erythroid-2 related factor 2 (Nrf2), PGC-1α/Nrf2 pathway. This signaling pathway facilitates interaction with antioxidant response elements (ARE), thereby initiating an upregulation in the expression of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and mitochondrial biogenesis. In both cases, whether involving healthy animals or individuals engaged in physical exercise, supplementation with antioxidant scavengers leads to a reduction in the expression and activity of PGC-1α, SOD, CAT, and GPX across various tissues, which is not observed with indirect antioxidants. The preventive role of physical exercise against chronic OS is avoided when executed in conjunction with supplementation of scavenger antioxidants. However, similar to exercise, the indirect antioxidant apigenin can activate the PGC1-α/Nrf2 signaling pathway. Here, we summarize evidence supporting apigenin as a non-nutritional supplement that could enhance the adaptive effects of exercise, improving the endogenous antioxidant defense. Therefore, apigenin could be an interesting supplement to enhance the endogenous antioxidant adaptation induced by exercise in healthy subjects, but also to improve the effectiveness of exercise to prevent oxidative stress-associated diseases.
El estrés oxidativo (OS) ocurre cuando el sistema de defensa antioxidante es sobrepasado por el predominio de especies reactivas de oxígeno (ROS) y factores prooxidantes. Varias enfermedades como la hipertensión, la resistencia a la insulina, la diabetes mellitus tipo 2 y enfermedades neurodegenerativas se caracterizan por un OS crónico. El ejercicio físico constituye una herramienta asequible para prevenir o mejorar estas enfermedades. Sin embargo, durante la actividad física, se producen ROS agudas que inducen una activación en la vía PGC-1α/Nrf2. Esta vía de señalización facilita la interacción con los elementos de respuesta antioxidante (ARE), iniciando así una regulación que permite la expresión de enzimas antioxidantes, incluidas SOD, CAT, GPX y biogénesis mitocondrial. En ambos casos, ya sea que se trate de animales sanos o de individuos que practican ejercicio físico, la suplementación con antioxidantes "scavengers" conduce a una reducción en la expresión y actividad de PGC-1α, SOD, CAT y GPX en varios tejidos, lo que no se observa con antioxidantes "indirectos". El papel preventivo del ejercicio físico contra el OS crónico se atenúa cuando se realiza en conjunto con la suplementación de antioxidantes "scavengers". Sin embargo, de manera similar al ejercicio, la apigenina es un antioxidante "indirecto" que puede activar la vía de señalización PGC1-α/Nrf2. Aquí, resumimos la evidencia que respalda a apigenina como un suplemento no-nutricional que podría mejorar los efectos adaptativos del ejercicio, mejorando la defensa antioxidante endógena de sujetos sanos que no tienen suficiente tiempo para hacer ejercicio.
RESUMO
This review analyzes the effects of high intensity interval training (HIIT) on muscle and cardiovascular fitness and body composition in teenagers. A search was carried out in international databases, finding 145 papers and selecting five for analysis. In all the reviewed manuscripts, peak oxygen uptake improved after HIIT. In the three manuscripts that measured muscle strength, it also increased. We conclude that HIIT improves muscle strength and cardiovascular fitness in school age children. A 12 weeks protocol with three 12-minute sessions per week would be ideal.
Assuntos
Humanos , Masculino , Feminino , Adolescente , Treinamento Intervalado de Alta Intensidade/métodos , Consumo de Oxigênio/fisiologia , Composição Corporal/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Ensaios Clínicos Controlados como Assunto , Força Muscular/fisiologiaRESUMO
Sedentarism, overweight and malnutrition generate an increase in the production of reactive oxygen species leading to a state of chronic oxidative stress. In patients with type 2 diabetes mellitus, oxidative stress alters pancreatic insulin secretion and the actions of the hormone on target cells, contributing to the development of micro and macrovascular complications. During physical exertion a state of transient oxidative stress occurs. As a consequence, the organism generates multiple physiological adaptations to these repetitive stimuli. Physical exercise is beneficial for type 2 diabetes mellitus but there is a paucity of information about the effects of physical exercise on biomarkers of oxidative stress in patients with the disease. We herein try to elucidate if the effects of exercise on oxidative stress can help in the prevention and treatment of type 2 diabetes mellitus and which is the most effective modality of physical exercise to reduce oxidative stress markers.