The effects of intensive, moderate and downhill treadmill running on human blood lymphocytes expressing the adhesion/activation molecules CD54 (ICAM-1), CD18 (β2 integrin) and CD53

Abstract

This study examined the effects of intensive, moderate and downhill treadmill running on blood lymphocyte expression of adhesion/activation (AA) molecules. Trained subjects completed three treadmill-running protocols of identical duration: (1) an intensive protocol at 80% VO2max to volitional exhaustion, (2) a moderate protocol at 60% VO2max and (3) a -10% downhill (eccentric) protocol at 80% VO2max. Blood samples were taken before, immediately after, 1 and 24 h after exercise. Isolated lymphocytes were assessed for expression of the AA molecules CD54, CD18 and CD53 by flow cytometry. Lymphocyte counts increased immediately after all running protocols. Lymphocytopenia was observed 1 h after the intensive and eccentric protocols only. Plasma creatine kinase increased 24 h after the downhill protocol only. Increases in the number and percentage of CD54+, CD18bright and CD53bright lymphocytes were observed immediately after the intensive and eccentric protocols, with the numbers falling below pre-exercise values at 1 h post-exercise for all protocols. No differences were found between the intensive protocol and the eccentric protocol at the same relative intensity. Analysis of lymphocyte subsets showed that the total number of CD3+, CD4+, CD8+ and CD56+ lymphocytes increased after the intensive protocol before falling below pre-exercise values at 1 h post-exercise. A relatively greater mobilisation of CD56+ and CD8+ cells accounts for the changes in CD54+, CD18bright and CD53bright cell populations. Lymphocytes that enter and exit the circulation following exercise express high levels of AA molecules, which may mediate extravasation and post-exercise lymphocytopenia. This effect appears to be influenced by exercise intensity and not muscle damage.

Effects of ultra-marathon on circulating DNA and mRNA expression of pro- and anti-apoptotic genes in mononuclear cells

“…There are diVerent explanations for the lymphopenia during the recovery period. While Simpson et al reXected an extravasation of speciWc lymphocyte populations (Simpson et al 2006), Mars et al concluded that apoptosis could be a cause for this phenomenon (Mars et al 1998). On the other hand, in a study reported by Steensberg et al, lymphocyte apoptosis after 2.5 h of treadmill run did not contribute to post-exercise lymphopenia (Steensberg et al 2002).…”

Investigating performance and lung function in a hot, humid and ozone-polluted environment

“…The V : O 2 max test (Simpson et al 2006) was initiated with the participant running at a speed of 10 km h -1 and 0% gradient. The speed of the treadmill was increased by 3 km h -1 every 3 min until achieving a maximum speed of 16 km h -1 .…”

Prolonged exercise does not cause lymphocyte DNA damage or increased apoptosis in well-trained endurance athletes

“…These, together with the exercise-induced altered cell surface receptor expression (Mooren et al 2004;Simpson et al 2006), loss of mitochondrial transmembrane potential (Wang and Huang 2005;Hsu et al 2002), release of apoptosis-inducing-factor (Curtin and Cotter 2003) and the inXammatory stimulus following tissue microtrauma (Mooren et al 2004), create the ideal milieu for DNA damage and apoptosis in circulating lymphocytes.…”