Effects of different durations of exercise on macrophage functions in mice

Abstract

The effects of differing durations of daily exercise on macrophage functions in mice were studied. Male ICR mice aged 4 wk were divided into five groups: a nonexercise group (control) and four exercise groups with differing daily exercise durations of 15--120 min (Exr groups). The exercise applied was 5 days/wk treadmill running at 13 m/min for 12 wk. The potentiation of the phagocytosis function of the reticuloendothelial system and the glucose consumption of peritoneal macrophages in the Exr 30, 60, and 120 groups were significantly higher than those in the control group. Superoxide anion production of peritoneal macrophages in both the absence and the presence of phorbol 12-myristate 13-acetate in the Exr 60 and 120 groups was significantly higher than that in the control group. The acid phosphatase and beta-glucuronidase activities of peritoneal macrophages in the Exr 30, 60, and 120 groups were significantly increased. These results suggest that treadmill running exercise for at least 30 min/day (30--120 min) effectively enhances macrophage functions in mice. These data provide preliminary evidence indicating that chronic exercise-induced increases in phagocytic activity exhibit a dose-dependent relationship with exercise duration.

Intensity-controlled treadmill running in mice: cardiac and skeletal muscle hypertrophy

“…Males had larger extensor digitorum longus muscles, but soleus muscle weight was similar. Other studies report varying results: 20-24% increased (39) and unchanged (1,19) skeletal muscle mass, and increased cross-sectional area (19,33) and GATA-2 expression (hypertrophy marker), after 4-12 wk of training (19,33). Interestingly, skeletal muscle growth occurs in mice in response to endurance training, contrary to observations in humans (4).…”

“…3, allometric scaling greatly enhances comparison of V O 2 in animals with different weights. Reports of long-term running in mice have reported decreased (34,40,44) or unchanged (1,19,31,33,37,39) body mass, whereas swimming yielded an increase (24). In a survey of 100 recent transgenic mice studies at PubMed, body mass ranged between 17 and 74 g and age between 26 days and 12 mo.…”

Immunological responses of male White Leghorn chicks kept on ochratoxin A (OTA)-contaminated feed

“…The phagocytic activity of the reticuloendothelial system was determined by measuring clearance of colloidal carbon from the peripheral blood, as described previously by Sugiura et al (2001), with minor modifications adapted to chicks. Briefly, Black Indian Ink (Pelikan, 4001) was centrifuged at 3000 x g for 30 min and the supernatant fraction was collected and then injected into the right wing vein (at 1 ml/Kg body weight [BW]) of 10 14-day-old chicks/group.…”

Efeitos do estresse agudo de contenção, do estresse crônico de natação e da administração de glutamina sobre a liberação de superóxido por macrófagos alveolares de ratos

“…A resposta frente ao exercício físico depende da idade do animal, do tipo, da duração e da intensidade do esforço realizado 7 e do tipo celular estudado 8 . Neste último aspecto, as células imunes, a depender do tipo, respondem de forma diferente aos hormônios, em especial, os do estresse 1 .…”

“…Neste último aspecto, as células imunes, a depender do tipo, respondem de forma diferente aos hormônios, em especial, os do estresse 1 . Os macrófagos parecem estar entre as células imunes mais responsivas ao exercício físico 8,9 .…”