Nonselective ? blockade attenuates the recruitment of CD62L? T lymphocytes following exercise

Abstract

Exercise induces a selective redistribution of CD62L(-) T lymphocytes. This study examined the effects of beta adrenergic receptor blockade on this phenomenon. Twelve healthy men were exercised to exhaustion on a treadmill prior to and following 1 week of treatment with the nonselective beta antagonist propranolol or the beta1 selective antagonist metoprolol. Dynamic exercise resulted in a significant lymphocytosis (p < 0.001). CD8(+)CD62L(-) T cells showed a greater than 3-fold increase in response to exercise (p < 0.001) as compared to CD8(+)CD62L(+) T cells, which showed a more modest increase. Treatment with the nonselective beta antagonist propranolol significantly attenuated the preferential increase of circulating CD8(+)CD62L(-) lymphocytes (p = 0.01) but had no effect on CD8(+)CD62L(+) T cells. Treatment with the beta1 selective antagonist metoprolol did not affect the response of either subset. Our findings replicate a prior study indicating that CD62L expression influences T lymphocyte trafficking in response to exercise and extends those findings by showing that this phenomenon is mediated, in part, via the beta2-adrenergic receptor.

Selective Mobilization of Cytotoxic Leukocytes by Epinephrine

“…The epinephrine-induced mobilization of effector CD8 + T cells is consistent with previous studies of increased effector CCR7 2 / CD62L 2 CD45RA + CD8 + T cell numbers after stress or catecholamine administration (19,22,25). These effector CD8 + T cells represent a stage of T cell differentiation occurring late in the immune response, and are hence called terminally differentiated cytotoxic T cells.…”

“…We show that stresslike increases in epinephrine concentrations invoke a specific increase in immune subpopulations with cytotoxic effector potential, namely, effector CD8 + T cells It has been repeatedly demonstrated that the number of immune cells increases after physical exercise or mental stress, with the most pronounced increases occurring in NK cell and CD8 + cytotoxic T cell counts (3,5,16,34), whereas both populations are decreased when endogenous catecholamines are suppressed by stellate ganglion block (40). These effects are caused by adrenal medullary epinephrine binding to b2-adrenoceptors on PBMCs, with high and intermediate levels of b2-adrenoceptor expression on NK cells and cytotoxic T cells, respectively (1,3,7,8,19,33,41). Our findings substantially expand these previous findings in showing that the epinephrine-induced increase in circulating immune cells is highly specific to cytotoxic effector subtypes, namely, effector CD8 + T cells, g/d T cells, NKT-like cells, cytotoxic NK cells, and proinflammatory monocytes, whereas no change is seen for cells lacking any cytotoxic potential, namely, CD4 + T cells, CD8 + T cells at their early stage of differentiation, immunomodulatory NK cells, and conventional monocytes.…”

“…Stress as well as diurnal increases in SNS activity mobilize cells with low expression of Lselectin (CD62L) and high expression of integrin LFA-1 (CD11a) such as effector memory (EM) and effector CD8 + T cells, CD16 to changes in catecholaminergic activity (10,(16)(17)(18)(19)(20)(21)(22)(23)(24)(25). Along with the CD62L 2 CD11a bright phenotype, effector immune cells are generally characterized by high expression of inflammatory chemokine receptors, such as CCR5, CXCR1, CXCR3, and CX3CR1 (26)(27)(28).…”

Effects of laboratory versus field exercise on leukocyte subsets and cell adhesion molecule expression in children

“…As previously described (Mills et al 1999), ow cytometry using CellQuest software (FACSCalibur, Becton Dickinson, San Jose, Calif.) was used to quantify leukocytes and lymphocyte subsets and CD62L and CD54 expression. A complete blood count (CBC) analysis was performed by using a Coulter STKS CBC Counter.…”

Respostas hormonais e imunes agudas decorrentes do treinamento de força em bi-set

“…Os efeitos deste tipo de exercício físico sobre o aumento no número de leucócitos circulantes são mediados, pelo menos em parte, pela ativação do sistema nervoso simpático 29 e aumento agudo dos níveis séricos de catecolaminas durante o exercício 30 .…”