Abstract
Immunosenescence is characterized by deterioration of the immune system caused by aging which induces changes to innate and adaptive immunity. Immunosenescence affects function and phenotype of immune cells, such as expression and function of receptors for immune cells which contributes to loss of immune function (chemotaxis, intracellular killing). Moreover, these alterations decrease the response to pathogens, which leads to several age-related diseases including cardiovascular disease, Alzheimer's disease, and diabetes in older individuals. Furthermore, increased risk of autoimmune disease and chronic infection is increased with an aging immune system, which is characterized by a pro-inflammatory environment, ultimately leading to accelerated biological aging. During the last century, sedentarism rose dramatically, with a concomitant increase in certain type of cancers (such as breast cancer, colon, or prostate cancer), and autoimmune disease. Numerous studies on physical activity and immunity, with focus on special populations (i.e., people with diabetes, HIV patients) demonstrate that chronic exercise enhances immunity. However, the majority of previous work has focused on either a pathological population or healthy young adults whilst research in elderly populations is scarce. Research conducted to date has primarily focused on aerobic and resistance exercise training and its effect on immunity. This review focuses on the potential for exercise training to affect the aging immune system. The concept is that some lifestyle strategies such as high-intensity exercise training may prevent disease through the attenuation of immunosenescence. In this context, we take a top-down approach and review the effect of exercise and training on immunological parameters in elderly at rest and during exercise in humans, and how they respond to different modes of training. We highlight the impact of these different exercise modes on immunological parameters, such as cytokine and lymphocyte concentration in elderly individuals.
Highlights
Maha Sellami 1, Maha Gasmi 2, Joshua Denham 3, Lawrence D
This review focuses on the potential for exercise training to affect the aging immune system
Timmerman et al [81] reported that 12 weeks of aerobic and resistance exercise training lowered (CD14+, Cluster of differentiation 16 (CD16)+) monocyte frequencies in blood of older adults, while no changes were observed in toll-like receptor 4 (TLR4) expression, a type of protein playing an important role in innate immunity
Summary
Immunosenescence or immunopause is a complex, multifactorial aging-related phenomenon characterized by a series of biological events, including (a) alteration of immune function, quantified by a reduction in humoral and cellular immunity, (b) increase in the inflammatory and oxidation background (inflammaging and oxi-inflammaging), and (c) production and release of auto-antibodies leading to the insurgence of autoimmune disorders, as briefly overviewed in Table 1 [1]. With advanced age, Abbreviations: ACSM, American College of Sports Medicine; APC, antigen presenting cell; CCR7, C-C chemokine receptor type 7; CD4, cluster of differentiation 4; CD8, cluster of differentiation 8; CD11b, cluster of differentiation 11b; CD18, cluster of differentiation 18; CD19, cluster of differentiation 19; CD28, cluster of differentiation 28; CD45RA, cluster of differentiation 45RA; CD45RO, cluster of differentiation 45RO; CD56, cluster of differentiation 56; CD62L, cluster of differentiation 62 ligand; CD94, cluster of differentiation 94; CD158, cluster of differentiation 158; CK, creatine kinase; CMV, cytomegalovirus; con-A, concanavalin A; CRP, C-reactive protein; CXCR1, C-X-C chemokine receptor type 1; CXCR2, C-X-C chemokine receptor type 2; DC, dendritic cell; EEE, exercise energy expenditure; EPC, endothelial progenitor cells; HLADR, Human Leukocyte Antigen – antigen D Related; HR, heart rate; HRmax, maximum heart rate; HRR, heart rate reserve; HSC, hematopoietic stem cells; hsCRP, highly sensitive C-reactive protein; hTERT, human telomerase reverse transcriptase; IFN, interferon; IFN-γ, interferon-gamma; IL-1, interleukin 1; IL1-β, interleukin 1-beta; IL-2, interleukin 2; IL-4, interleukin 4; IL-6, interleukin 6; IL12, interleukin 12; IL-13, interleukin 13; KLR, killer lectin-like receptor; KLR61, killer lectin-like receptor 61; miRNA, microRNA; mRNA, RNA messenger; NK, natural killer; NKCA, natural killer cytotoxic activity; NKCC, natural killer cellular citotoxicity; NR, not reported; PBMC, peripheral blood mononuclear cell; PHA, phitoemagglutinin; PIST, prolonged intermittent sprinting training; PPD, purified protein derivative; PWM, poke weed mitogen; RM, repetition maximum; RT, resistance training; SLEC, short-lived effector cells; ST, sprint training; TGF, transforming growth factor; TGF-β1, transforming growth factor beta 1; TLR2, Toll like receptor 2; TLR4, Toll like receptor 4; TNF-α, tumor necrosis factor alpha; URTI, upper respiratory tract infection; WBC, white blood cell; WHO, World Health Organization
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
