Exercise Induced Alterations in Rat Monocyte Number, Morphology, and Function

The purpose of this study was to verify the histophysiological alterations in monocytes and macrophages induced by short periods of exercise. Male Wistar rats (age = 2 months, body weight = 200g) were divided into seven groups (N=6 each): sedentary control (C), groups exercised (swimming) at low intensity for 5 (5L), 10 (10L), and 15 minutes (15L), and groups exercised at moderate intensity for 5 (5M), 10 (10M) or 15 minutes (15M). At moderate intensity the animals carried a load of 5% of body weight on their backs. Blood monocytes were evaluated for quantity and morphology, and peritoneal macrophages were analyzed for quantity and phagocytic activity. Data were analyzed using ANOVA and Tukey’s post hoc test (p ≤0.05). Low intensity groups and 5M exhibited an increase in monocyte levels when compared with the control. There was an increase in monocyte cellular area for the 5L, 10L, 5M and 10M groups; monocyte nuclear area increased for the 10L, 5M and 10M groups in comparison with the control. There was an increase in peritoneal macrophages for the 15L, 10M, 15M and decrease for the 5M group. Macrophage phagocytic capacity increased for low intensity groups and for 10M group. The exercise performed for short periods modulated macrophage levels and function, and monocyte levels and morphology, in an intensity-dependent manner. The sum of acute responses observed in this study may exert a protective effect against sickness and may be used to improve health and lifespan

Phagocytic responses of peritoneal macrophages and neutrophils are different in rats following prolonged exercise

OBJECTIVE: To analyze the effects of exhausting long-duration physical exercise (swimming) sessions of different durations and intensities on the number and phagocytic capacity of macrophages and neutrophils in sedentary rats. INTRODUCTION: Exercise intensity, duration and frequency are important factors in determining immune response to physical effort. Thus, the effects of exhausting long-duration exercise are unclear. METHODS: Wistar rats were divided into two groups: an untreated group (macrophage study) and oyster glycogen-treated rats (neutrophil study). In each group, the animals were subdivided into five groups (10 rats per group): unexercised controls, an unadapted low-intensity exercise group, an unadapted moderate-intensity exercise group, a preadapted low-intensity exercise group and a preadapted moderate-intensity exercise group. All exercises were performed to exhaustion, and preadaptation consisted of 5, 15, 30 and 45 min sessions. RESULTS: Macrophage study: the number of peritoneal macrophages significantly decreased (9.22 ± 1.78 x 10(6)) after unadapted exercise but increased (21.50 ± 0.63 x 10(6)) after preadapted low-intensity exercise, with no changes in the moderate-intensity exercise group. Phagocytic capacity, however, increased by more than 80% in all exercise groups (low/moderate, unadapted/preadapted). Neutrophil study: the number of peritoneal neutrophils significantly decreased after unadapted (29.20 ± 3.34 x 10(6)) and preadapted (50.00 ± 3.53 x 10(6)) low-intensity exercise but increased after unadapted (127.60 ± 5.14 x 10(6)) and preadapted (221.80 ± 14.85 x 10(6)) moderate exercise. Neutrophil phagocytic capacity decreased by 63% after unadapted moderate exercise but increased by 90% after corresponding preadapted sessions, with no changes in the low-intensity exercise groups. CONCLUSION: Neutrophils and macrophages of sedentary rats respond differently to exercise-induced stress. Adaptation sessions reduce exercise-induced stress on the immune system

Efeito do exercício agudo de curta duração em leucócitos circulantes e linfócitos teciduais de ratos

Acute exercise sessions produce an immune system response, possibly leading to cessation, loss of continuity or performance decrement during the training period, caused by the increased upper respiratory infections (IVASs) susceptibility. Considering that lymphocyte cells have to fight infections and that sedentary subjects in poor physical condition should enroll physical programs of low intensity and volume, the aim of this study was to evaluate the amount of circulating leukocytes and lymphocytes as well as the mesenteric lymphocytes tissues, and the proliferative capacity of tissues lymphocytes in male Wistar rats submitted to acute sets of 5 and 15 minutes of low and moderate intensities. Results show leukocytosis and lymphocytosis in both groups 5 and 15 minutes of low and moderate intensities, increased tissue lymphocytes counting in the 5 minutes group of low intensity and in the 5 and 15 minutes groups of moderate intensity, in general, no alteration in the T cellular proliferative capacity, however with reduction in B lymphocytes in the 5 and 15 minutes groups of low intensity and in the 5 minutes of moderate intensity. The relevance and the clinical meaning of these alterations need to be well clarified for a better understanding of the complex triad: physical exercise, immunological responses and infections susceptibility after submaximal sets of short term.Sessões agudas promovem respostas no sistema imunológico, podendo acarretar desistência, não continuidade ou queda no desempenho nos programas de exercícios, pela aumentada susceptibilidade às infecções das vias aéreas superiores (IVASs). Considerando que os linfócitos desempenham funções no combate às infecções e que indivíduos sedentários com baixo nível de aptidão física, devam iniciar programas de treinamento com baixo volume e intensidade, o estudo teve como objetivo avaliar a contagem de leucócitos e linfócitos circulantes e dos linfócitos teciduais mesentéricos, bem como a capacidade proliferativa dos linfócitos teciduais em ratos machos "Wistar" submetidos a sessões agudas de cinco e 15 minutos nas intensidades leve e moderada. Os resultados mostram leucocitose e linfocitose nos grupos cinco e 15 minutos em ambas as intensidades, aumentada contagem de linfócitos teciduais nos grupos cinco minutos leve bem como cinco e 15 minutos moderado, de forma geral, nenhuma alteração na resposta proliferativa celular T, porém com diminuição na resposta celular B nos grupos cinco e 15 minutos leve e cinco minutos moderado. A relevância e o significado clínico dessas alterações precisam ser mais bem esclarecidos para o melhor entendimento da complexa tríade: exercício físico, respostas imunológicas e susceptibilidade a infecções, após sessões submáximas de curta duração

Estratégias nutricionais no tratamento da síndrome da caquexia associada ao câncer

A síndrome da caquexia é considerada uma doença crônica degenerativa inflamatória, profundamente relacionada com o aumento de fatores pró-inflamatórios. O efeito de fatores pró-inflamatórios, é contrabalançado pelo efeito de fatores anti-inflamatórios. A perda de peso é um dos sintomas clínicos mais marcantes, essa diminuição de peso corporal, principalmente de massa gorda de massa magra era atribuída à anorexia e ao aumento do gasto energético. No entanto, a administração de suplementos nutricionais enteral ou paraenteralmente não reverte esses sintomas, refutando, dessa forma, a hipótese de que deficiência de nutrientes é o agente causador da caquexia associada ao câncer. Atualmente, acredita-se que fatores produzidos pelo tumor e fatores produzidos pelo hospedeiro induzem a anorexia e as alterações metabólicas que resultam no quadro de caquexia. A fim de combater a inflamação na doença crônica, nosso grupo tem atualmente adotado estratégias nutrucionais em modelo animal de caquexia associada ao câncer. Os efeitos dos diferentes nutrientes frente aos danos ocasionados pela sindrome da caquexia associada ao câncer são abordados na presente revisão