Changes in Glucose and Glutamine Lymphocyte Metabolisms Induced by Type I Interferon α

In lymphocytes (LY), the well-documented antiproliferative effects of IFN-α are associated with inhibition of protein synthesis, decreased amino acid incorporation, and cell cycle arrest. However, the effects of this cytokine on the metabolism of glucose and glutamine in these cells have not been well investigated. Thus, mesenteric and spleen LY of male Wistar rats were cultured in the presence or absence of IFN-α, and the changes on glucose and glutamine metabolisms were investigated. The reduced proliferation of mesenteric LY was accompanied by a reduction in glucose total consumption (35%), aerobic glucose metabolism (55%), maximal activity of glucose-6-phosphate dehydrogenase (49%), citrate synthase activity (34%), total glutamine consumption (30%), aerobic glutamine consumption (20.3%) and glutaminase activity (56%). In LY isolated from spleen, IFNα also reduced the proliferation and impaired metabolism. These data demonstrate that in LY, the antiproliferative effects of IFNα are associated with a reduction in glucose and glutamine metabolisms

Effect of aerobic training on macrophage metabolism obtained from old rats

Com o avanço da idade observamos a queda na eficiência do Sistema Imunológico, estando relacionada ao aumento da morbidade e mortalidade em idosos. Dentre as células do sistema imunológico encontramos os macrófagos que garantem ao organismo a capacidade de defesa contra infecções, proliferação de células tumorais e reparo de tecidos. Uma das formas de reverter ou até mesmo restaurar algumas das funções imunológicas comprometidas com o processo de envelhecimento é a utilização da prática de exercício aeróbio moderado. Por este motivo, estudamos o efeito do treinamento moderado em natação sobre a função e o metabolismo de macrófagos de ratos envelhecidos. Em macrófagos obtidos da cavidade peritoneal, observamos uma melhora da capacidade funcional, através do aumento das funções de aderência, quimiotaxia e produção de peróxido de hidrogênio (H2O2) e óxido nítrico (NO-), que foram acompanhadas pelo aumento no metabolismo de glicose (aumento de consumo e da enzima hexoquinase), contribuindo para a melhora da função imune no envelhecimento.Disorders of the immune function contribute to the high incidence of infections and cancer among elderly people. Macrophages play a crucial role in immune response, destroying bacteria, parasites, viruses and tumour cells through various mechanisms of action. Exercise is able to induce changes and modulate the immune response. The aim of the present work was to evaluate the function and metabolism of macrophages obtained from old rats submitted to moderate exercise training. Sedentary adult (2 4 months), old (15 18 months) and trained old rats were studied. The results show an increase in the function of macrophages obtained from the peritoneal cavity of trained old rats compared with old rats, regarding chemotaxis, hydrogen peroxide and nitric oxide production, as well a enhanced glucose consumption and increased maximal activity of the enzymes hexoquinase and glutaminase. In summary, our results indicate that exercise (moderate training) stimulates some functional aspects of macrophages of old rats, with a concomitant increase in glucose metabolism

Effects of dietary restriction or swimming on lymphocytes and macrophages functionality from old rats

Although aging compromises the functionality of macrophages (M Phi) and lymphocytes (LY), and dietary restriction (DR) and exercise partially counterbalance immunosenescence, it is unknown what effects of both strategies have on the functionality of these immune cells. Rats were randomly distributed into adult control (AD), older group (OLD), older submitted to 50% of DR (DR) and older submitted to swimming (EX) (n = 10 in each group). The function of immune cells (proliferative index, phagocytic capacity and H2O2 production), the weight and protein content of lymphoid organs (thymus and spleen), plasma glutamine concentration, interleukins (IL-1, IL-2, IL-6) and, immunoglobulins (IgA and IgG) were analysed. There was an increase of 74% in body weight in aged animals as compared with the AD group, while body weight reduced 19% in the DR as compared with the OLD group. Swimming training stimulated M Phi phagocytosis, while the EX group presented a decrease of the proliferative capacity of LY from the mesenteric lymph nodes (44% and 62%, respectively), when stimulated with ConA and LPS as compared with the old rats. These data demonstrated that DR and exercise affects differentially M Phi and LY function43211312