Seven days’ around the clock exhaustive physical exertion combined with energy depletion and sleep deprivation primes circulating leukocytes

Abstract

Both exhaustive physical exertion and starvation have been reported to induce depression of immune function. The aim of the present study was to investigate the inflammatory environment and state of activation and mediator-producing potential of circulating leukocytes during prolonged physical activity with concomitant energy and sleep deprivation. Eight well-trained males were studied during 7 days of semi-continuous physical activity. Sleep was restricted to about 1 h/24 h, energy intake to 1.5- 3.0 MJ/24 h. Blood was drawn at 07.00 A.M.: on days 0, 2, 4, and 7. Plasma levels of inflammation markers were measured. The response of circulating leukocytes to lipopolysaccharide (LPS; 1 microg mL(-1)), and the effect of added hydrocortisone (10 and 100 nmol L(-1)), were measured in the supernatant after 3 h of incubation in an ex vivo whole blood model. Activation of leukocytes steadily increased as measured by plasma matrix metalloproteinase-9, tumour necrosis factor-alpha, interleukin-1beta, and interleukin-6. Inhibitors of systemic inflammation were either unaltered (tissue inhibitor of matrix metalloproteinase-1) or elevated (plasma interleukin-1 receptor antagonist). Cortisol levels increased on days 2 and 4, but thereafter reverted to baseline values. The leukocytes responded to LPS activation with increasing release of inflammatory cytokines throughout the study period. The anti-inflammatory potency of hydrocortisone decreased. Prolonged multifactorial stress thus activated circulating immune cells and primed them for an increased response to a subsequent microbial challenge.

Oxidative stress, inflammation, and muscle soreness in an 894-km relay trail run

“…We also observed an increase in leukocytes, particularly neutrophils, confirming the effect previously described following ultra-endurance running (e.g. Gundersen et al 2006) and an ultra-endurance cycle relay (Bessa et al 2008;Neubauer et al 2008).…”

Immune Outcomes of Paradoxical Sleep Deprivation on Cellular Distribution in Naive and Lipopolysaccharide-Stimulated Mice

“…Regarding the general reduction of immune cell populations in saline-treated mice, these data are in accordance with previous findings showing decreased circulating lymphocyte populations after PSD in humans [25,26] and rodents [17,18,27] . The current study expanded our previous findings [18] by demonstrating that this reduction occurs not only in circulating lymphocytes but also in spleen and in other cell subtypes, such as macrophages, NK cells and dendritic cells.…”

The impact of sleep restriction while performing simulated physical firefighting work on cortisol and heart rate responses

“…07:00) cortisol levels were also investigated among personnel completing a 7-day military training exercise that comprised semicontinuous physical work and extreme sleep restriction (1 h per 24 h; Gundersen et al 2006;Lundeland et al 2012). Similar to the current study, cortisol levels increased from baseline to day 4 (Gundersen et al 2006) and 5 (Lundeland et al 2012) of training, but returned towards baseline by the last day of training. Elevated morning cortisol levels have been associated with several adverse psychological health effects including the onset of depression, as well as low positive affect (Harris et al 2000;Steptoe et al 2007).…”

“…Serum morning (i.e. 07:00) cortisol levels were also investigated among personnel completing a 7-day military training exercise that comprised semicontinuous physical work and extreme sleep restriction (1 h per 24 h; Gundersen et al 2006;Lundeland et al 2012). Similar to the current study, cortisol levels increased from baseline to day 4 (Gundersen et al 2006) and 5 (Lundeland et al 2012) of training, but returned towards baseline by the last day of training.…”