Endotoxaemia, production of tumour necrosis factor alpha and polymorphonuclear neutrophil activation following strenuous exercise in humans.

To examine whether endotoxaemia accompanying long-term, strenuous physical exercise is involved in exercise-induced increase in plasma tumour necrosis factor alpha (TNF-alpha) concentration and polymorphonuclear neutrophil (PMN) activation, 14 male recreational athletes [mean age 28 (SEM 1) years] were studied. Exercise consisted of a 1.5-km river swim, a 40-km bicycle race, and a 10-km road race.

Effects of training on exercise-induced muscle damage and interleukin 6 production.

To address the question of whether the increased plasma concentration of interleukin 6 (IL-6) following strenuous muscular work could be related to exercise-induced muscle damage, 5 moderately active male volunteers underwent two isokinetic exercise sessions in the eccentric mode, separated by a period of 3 weeks during which the subjects underwent five training sessions. Before training, exercise was followed by severe muscle pain (delayed-onset muscle soreness; DOMS), and by significant increases in plasma IL-6 level and serum myoglobin concentration (SMb) (P < 0.001).

Possible in vivo tolerance of human polymorphonuclear neutrophil to low-grade exercise-induced endotoxaemia.

To address the question of whether translocation of bacterial lipopolysaccharide (LPS) into the blood could be involved in the process of exercise-induced polymorphonuclear neutrophil (PMN) activation, 12 healthy male subjects who took part in a sprint triathlon (1.5 km river swim, 40 km bicycle race, 10 km road race) were studied. While there was no detectable amount of endotoxin in the blood samples drawn at rest, exercise was followed by the appearance of circulating endotoxin molecules at the end of competition in four subjects, and after one and 24 h recovery in three and seven athletes, respectively.

Piroxicam fails to reduce myocellular enzyme leakage and delayed onset muscle soreness induced by isokinetic eccentric exercise.

To test the hypothesis that delayed onset muscular soreness (DOMS) following intense eccentric muscle contraction could be due to increased production of prostaglandin E(2) (PGE(2)), ten healthy male subjects were studied. Using a double-blind randomized crossover design, each subject performed two isokinetic tests separated by a period of at least 6 weeks: once with placebo, and once with piroxicam (Feldene((R))). They were given one capsule containing either placebo or piroxicam (20 mg) per day for 6 days with initial doses given starting 3 days prior to isokinetic testing.

Myocellular enzyme leakage, polymorphonuclear neutrophil activation and delayed onset muscle soreness induced by isokinetic eccentric exercise.

To address the question of whether delayed onset muscular soreness (DOMS) following intense eccentric muscle contraction could be due to increased production of the arachidonic acid derived product prostaglandin E2 (PGE2). 10 healthy male subjects were submitted to eccentric and concentric isokinetic exercises on a Kin Trex device at 60 degrees/s angular velocity. Exercise consisted of 8 stages of 5 maximal contractions of the knee extensor and flexor muscle groups of both legs separated by 1 min rest phases.

Anaphylatoxin C5a production during short-term submaximal dynamic exercise in man.

We studied the effects of short-term submaximal exercise on the plasma levels of myeloperoxidase ([MPO]) and C5a anaphylatoxin ([C5a]), taken as specific markers of polymorphonuclear neutrophil (PMN) and complement activation, respectively. Eleven young, healthy male volunteers were subjected to a constant-load concentric exercise on a cycle ergometer (20 min at 80% maximal oxygen uptake). Mean resting MPO and C5a concentrations were 437 +/- 113 and 0.

Blood levels of reduced/oxidized glutathione and plasma concentration of ascorbic acid during eccentric and concentric exercises of similar energy cost.

In an attempt to assess the possible oxidative stress associated with the transient exercise-induced activation of polymorphonuclear neutrophils (PMN), we compared the effects of eccentric and concentric exercises (downhill run: DR and uphill walk: UW, respectively) of equal duration (35 min) and similar energy cost (60% VO2max) on plasma levels of ascorbic acid ([AA]) and blood concentration of reduced ([GSH]) and oxidized ([GSSG]) glutathione. Eight healthy male subjects took part in this study. Plasma concentration of myeloperoxidase ([MPO]) was used as a specific marker of PMN activation.

Inflammatory response to strenuous muscular exercise in man.

Based on the humoral and cellular changes occurring during strenuous muscular work in humans, the concept of inflammatory response to exercise (IRE) is developed. The main indices of IRE consist of signs of an acute phase response, leucocytosis and leucocyte activation, release of inflammatory mediators, tissue damage and cellular infiltrates, production of free radicals, activation of complement, and coagulation and fibrinolytic pathways. Depending on exercise intensity and duration, it seems likely that muscle and/or associated connective tissue damage, contact system activation due to shear stress on endothelium and endotoxaemia could be the triggering mechanisms of IRE.

Effects of methylprednisolone on exercise-induced increases of plasma levels of polymorphonuclear elastase and myeloperoxidase in man. Preliminary results.

The aim of the present study was to verify whether a single oral dose of methylprednisolone could modulate the exercise-induced release of polymorphonuclear neutrophil (PMN) elastase and myeloperoxidase. Four healthy, male subjects were submitted to a 20 min downhill run (-20%) at 60% VO(2) max, 3 h after oral absorption of a placebo or a single dose of 32 mg methylprednisolone. A marked neutrophilia (+103% of basal PMN count; p < 0.

Plasma levels of polymorphonuclear elastase and myeloperoxidase after uphill walking and downhill running at similar energy cost.

This study was designed to compare the effects of eccentric and concentric exercises on blood polymorphonuclear neutrophil count (nPMN) and plasma levels of myeloperoxidase ([MPO]) and elastase ([EL]) used as markers of neutrophil (PMN) activation. Ten healthy male subjects underwent 2 periods of exercise of 20 min duration each at 60% VO2max on an inclined treadmill. They initially walked up a 5% grade (UW).

[Mobilization of leukocytes during sub-maximal dynamic exercise].

Increase of blood leucocytes induced by a dynamic exercise has been studied in 10 adult male subjects (age: 22 +/- 2 years; body weight 73 +/- 10 kg; VO2max: 54 +/- 8 ml O2/kg.min. The exercise consisted of a 20 minutes test on a cycle ergometer at a work rate eliciting a total energy expenditure roughly equal to 80% of the maximal aerobic power (80% VO2max).

[Hypotensive and edematogenic effects of carrageenan in the irradiated rat].

Iota carrageenan induces the same hypotensive effect in leucopenic and thrombopenic rats as in normal animals. This hypotensive activity depends on kininogen-kinins activation. In the irradiated rats, the inflammatory response to iota carrageenan is reduced.

[Activation of arachidonic acid].

Intravenous injection of arachidonic acid induces cardiovascular and respiratory effects due to its transformation into prostaglandins, This activation could take place not only in the platelets but also in the vacular wall. Platelet aggregation induced by arachidonic acid is not the main factor responsible of its cardiovascular actions.