Physical exercise and immunoscenescence: can we play for healthy ageing?

Aging is accompanied by the modifications and progressive dysfinction of systemic immunty. High and moderate intensity dynamic exercise can affect gene expression profiles of human white blood cells even after a single bout of exercise. However, it is not clear how the genes implied in immune system modulation may be regulated in response to muscle activity and whether the immune cells of elderly people can be responsive to the “exercise stimulus”. PURPOSE: To characterise the interplay of ageing and muscle activity in the process of immunosenescence we used a large-scale approach based on microarray analysis. METHODS: We evaluated the transcriptional profile of whole blood cells (WBCs) produced by single bouts of exercise at different intensities. Experiments have been carried out on two groups of ten healthy men of different age (50±5 and 70±5 years old) recruited locally. Both groups performed 30 min constant work rate cycle ergometry at 80% of their maximal O2 uptake (VO2 max) and at 60% VO2 max. RNA-stabilized blood samples were obtained 30 min before and 1hr after each constant load tests. Gene expression of WBCs was evaluated using whole genome microarray expression analysis with Affymetrix Human Gene 1.0 ST arrays. RESULTS: Results from GSEA (Gene Set Enrichment Analysis) highlights age-related differences at the baseline related to immune response , stress response, cellular metabolic pathways and cell death. In both groups the intensity of the exercise performed brought about slighlty different signature, and the patterns observed differed in function of age. Several known gene pathways related to cell proliferation, cellular metabolism, cytokine regulation, inflammation and cellular differentiation are modified. CONCLUSIONS: Ageing alters gene expression profile of imunocompetent cells. A single bout physical exercise can modulate the activity of immunocompetent cells and their interactions, and blood cells composition