N. M. Moyna

Stressor-induced alteration of cytokine production in multiple sclerosis patients and controls.

Objective We administered an acute psychological stressor to multiple sclerosis (MS) patients and normal controls to determine whether differences in subjective and physiological responses to stress may underlie the susceptibility of MS patients to stress-related exacerbations. Method Twenty-five MS patients (18 female, 7 male) and 25 age- and gender-matched controls participated in the study. They were asked to give a 5-minute videotaped speech defending themselves in a hypothetical scenario in which they were wrongly accused of stealing. Subjective and autonomic responses were monitored, and blood was sampled at baseline, 5, 20, and 60 minutes after the stressor to assess mitogen-stimulated production of interleukin-1 beta (IL-1 beta), interleukin-4 (IL-4), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma). Results MS patients and controls demonstrated similar subjective and physiological responses to the stressor that were independent of gender, mood, and disability status. The macrophage-derived cytokines IL-1 beta and TNF-alpha were increased during the stressor, and remained elevated through 60 minutes. Th1 lymphocyte-derived IFN-gamma production also was increased at 5 and 60 minutes relative to baseline; however, there was no change in the Th2 lymphocyte-derived cytokine IL-4. Conclusions These results favor the hypothesis that MS patients do not differ in stress response from normal controls; however, psychological stress may enhance cellular immune responses that would be potentially harmful to MS patients.

IMMUNOLOGIC RESPONSE TO ACUTE PSYCHOLOGICAL STRESS IN MS PATIENTS AND CONTROLS

To determine whether MS patients differ from healthy subjects in stress-related immune changes, we examined immunologic alterations following a public speaking task in 25 MS patients and 25 healthy controls. Both groups demonstrated similar autonomic, neuroendocrine and immunologic responses to acute stress. Neutrophils, monocytes, CD8+ suppressor/cytotoxic T-lymphocytes and NK-cells transiently increased, with parallel changes in NK-cell activity. T-cell proliferation declined at 20 min, followed by increased reactivity at 60 min relative to baseline. This data suggests that stress-induced immune alterations remain intact in MS patients, and may contribute to immune changes associated with disease exacerbation.

Exercise-induced alterations in natural killer cell number and function

AbstractTo study the effects of exercise on natural killer (NK) cell number and activity (NKCA) healthy male (n = 32) and female (n = 32) subjects were randomly assigned to an exercise or control condition. Exercise involved a continuous incremental protocol consisting of cycling for three periods of 6 min at work rates corresponding to 55%, 70% and 85% peak oxygen uptake (

Validity of the Borg Perceived Exertion Scale for Use in Semirecumbent Ergometry during Immersion in Water

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ANAEROBIC INDICES OF FREESTYLE SWIMMING PERFORMANCE IN TRAINED ADULT FEMALE SWIMMERS

). Blood samples were drawn at baseline, at 6 min, 12 min and 18 min during exercise, and at 2 h following completion of exercise. Relative to both baseline and control conditions, exercise resulted in an increase in the number of circulating lymphocytes. The proportion of T cells (CD3+) and B cells (CD19 +) significantly decreased, and NK cells (CD3−CD16+CD56+) increased throughout exercise. NKCA increased (P < 0.001) during the initial 6 min of exercise with no further changes observed, despite increases (P < 0.001) in the number and proportion of circulating NK cells during exercise at 70% and 85%

134 THE METABOLIC EFFECTS OF ORAL L-CARNITINE SUPPLEMENTATION ON BLOOD LACTATE ACCUMULATION

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