Protective role of 17-β-estradiol towards IL-6 leukocyte expression induced by intense training in young female athletes

Abstract

Exercise performed at a competitive level could deeply modify the immune system and the cytokine response of athletes. In this report, we demonstrated that young elite female artistic gymnasts (n = 16; age: 9–15 years) showed an increase of interleukin 6 (IL-6) and tumour necrosis factor alpha (TNF-α) mRNA expression in blood mononuclear cells (PBMCs), in comparison to girls performing the same sport at a recreational level (n = 16; age: 10–15 years). The increase of IL-6 and TNF-α mRNAs appeared to be directly linked to the intensity and duration of the training. Moreover, in elite athletes engaged in artistic gymnastics or in synchronised swimming (n =34; age: 9–15 years), IL-6 gene expression appeared to be modulated by the levels of circulating oestrogens: pre-pubertal athletes (n = 20; age: 11 ± 1 years) revealed a higher increase in IL-6 than pubertal athletes (n = 14; age: 14 ± 1.6 years). In pre-pubertal athletes, body mass index (BMI) percentile was inversely correlated with the increase of both IL-6 and TNF-α. The consequence of these events was the shift of the cytokine profile towards a pro-inflammatory status. These modifications, induced by training performed at an elite level, might negatively affect the growth of female children athletes.     

Exercise promotes IL-6 release from legs in older men with minor response to unilateral immobilization

Physical inactivity is a major contributor to low-grade systemic inflammation. Most of the studies characterizing interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) release from exercising legs have been done in young, healthy men, but studies on inactivity in older people are lacking. The impact of 14 days of one-leg immobilization (IM) on IL-6 and TNF-α release during exercise in comparison to the contralateral control (CON) leg was investigated. Fifteen healthy men (age 68.1?±?1.1?year (mean?±?SEM); BMI 27.0?±?0.4 kg·m²; VO₂max 33.3?±?1.6 ml·kg^?1·min^?1) performed 45?min of two-leg dynamic knee extensor exercise at 19.5?±?0.9 W. Arterial and femoral venous blood samples from the CON and the IM legs were collected every 15?min during exercise, and thigh blood flow was measured with ultrasound Doppler. Arterial plasma IL-6 concentration increased with exercise (rest vs. 45?min, main effect p?p?p?=?.085, effect size 0.28) higher in the IM leg compared to the CON leg (288 (95% CI: 213–373) vs. 220 (95% CI: 152–299) pg·min^?1, respectively). There was no release of TNF-α in either leg and arterial concentrations remained unchanged during exercise (p?>?.05). In conclusion, exercise induces more pronounced IL-6 secretion in healthy older men. Two weeks of unilateral immobilization on the other hand had only a minor influence on IL-6 release. Neither immobilization nor exercise had an effect on TNF-α release across the working legs in older men.     

The immune response to short-duration exercise in trained,eumenorrhoeic women

Few studies have characterised the immune response to exercise of different intensities and durations in women. In those that have, baseline hormone levels and training status were not always adequately controlled for. Here, leucocyte and cytokine profiles of 11 aerobically trained, eumenorrhoeic females (33 ± 5 years) in the early follicular phase of the menstrual cycle were characterised after 30-min exercise at 3 intensities: 90% lactate threshold (LT), LT, and 110% LT. Proposed cytokine response mediators were quantified: plasma lactate and basal oestradiol concentrations. Intensity-dependent increases occurred in total white blood cells and lymphocyte counts (P < 0.001). Elevated plasma IL-6 and IL-1ra concentrations post-exercise [F = 12.38, P < 0.01 and F = 7.65, P < 0.05, respectively] were not intensity-dependent, indicating that cytokine release may be better associated with exercise duration than intensity in trained women. Changes in plasma IL-1ra and basal oestradiol (ρ = ?0.893, P < 0.01) were correlated at intensities above LT only. These findings suggest a role for plasma sex hormones in moderating the exercise-induced immune response in women. However, the associations observed did not account for the magnitude of the cytokine response observed, and future studies should explore contributions of other potential mediators following short-duration exercise.     

Effects of AM3 (Inmunoferon®) on increased serum concentrations of interleukin-6 and tumour necrosis factor receptors I and II in cyclists

Abstract

The aims of this study were to examine the changes in plasma concentrations of inflammatory cytokines induced by training and competition in professional cyclists. We report the serum concentrations of interleukin-6 (IL-6), tumour necrosis factor alpha (TNF-α), tumour necrosis factor receptors I and II (TNFR-I and -II) in a prospective, randomized, double-blind trial involving the administration of AM3 (Inmunoferon®), an oral booster immunomodulator, or placebo to 16 professional cyclists (n=8 in each group) for 65 consecutive days. Serum was collected just before treatment began (baseline), at the end of pre-competition training, before the mountain stage of the competition (60 days), 4 h after finishing this stage (62 days), and 18 h after the fifth and last day of competition (65 days). To determine the normal levels of cytokines and soluble TNF receptors, individual samples from 14 moderately trained healthy controls were studied. After 60 days of training, the serum concentrations of IL-6 did not differ significantly from those at the beginning of the study for either group of cyclists (placebo and AM3). A significant rise was seen in IL-6 concentrations in both the AM3 and placebo groups at 62 days, 4 h after finishing the mountain stage. The increase was significantly greater in the placebo group than in the AM3 group. At 65 days of treatment, 18 h after the fifth and last day of competition, IL-6 concentrations were similar to those recorded at the end of the training, but were significantly higher in the placebo group than in the AM3 group. At the end of training, serum TNFR-I concentrations in both groups of cyclists were significantly lower than at baseline. The concentrations of serum TNFR-I and -II both 4 h after finishing the mountain stage and 18 h after the fifth and last day of competition were significantly higher than those recorded after training in both groups. Professional cycling competition is associated with increases in serum IL-6 and TNFR-I and -II concentrations. Inmunoferon treatment reduced significantly the concentrations of IL-6 but not those of TNFR-I and -II.     

Creatine supplementation does not decrease oxidative stress and inflammation in skeletal muscle after eccentric exercise

Abstract

Thirty-six male rats were used; divided into 6 groups (n = 6): saline; creatine (Cr); eccentric exercise (EE) plus saline 24 h (saline + 24 h); eccentric exercise plus Cr 24 h (Cr + 24 h); eccentric exercise plus saline 48 h (saline + 48 h); and eccentric exercise plus Cr 48 h (Cr + 48h). Cr supplementation was administered as a solution of 300 mg · kg body weight^?1 · day^?1 in 1 mL water, for two weeks, before the eccentric exercise. The animals were submitted to one downhill run session at 1.0 km · h^?1 until exhaustion. Twenty-four and forty-eight hours after the exercise, the animals were killed, and the quadriceps were removed. Creatine kinase levels, superoxide production, thiobarbituric acid reactive substances (TBARS) level, carbonyl content, total thiol content, superoxide dismutase, catalase, glutathione peroxidase, interleukin-1b (IL-1β), nuclear factor kappa B (NF-kb), and tumour necrosis factor (TNF) were analysed. Cr supplementation neither decreases Cr kinase, superoxide production, lipoperoxidation, carbonylation, total thiol, IL-1β, NF-kb, or TNF nor alters the enzyme activity of superoxide dismutase, catalase, and glutathione peroxides in relation to the saline group, respectively (P < 0.05). There are positive correlations between Cr kinase and TBARS and TNF-α 48 hours after eccentric exercise. The present study suggests that Cr supplementation does not decrease oxidative stress and inflammation after eccentric contraction.     

The effect of 14 weeks of vitamin D3 supplementation on antimicrobial peptides and proteins in athletes

Heavy training is associated with increased respiratory infection risk and antimicrobial proteins are important in defence against oral and respiratory tract infections. We examined the effect of 14 weeks of vitamin D₃ supplementation (5000 IU/day) on the resting plasma cathelicidin concentration and the salivary secretion rates of secretory immunoglobulin A (SIgA), cathelicidin, lactoferrin and lysozyme in athletes during a winter training period. Blood and saliva were obtained at the start of the study from 39 healthy men who were randomly allocated to vitamin D₃ supplement or placebo. Blood samples were also collected at the end of the study; saliva samples were collected after 7 and 14 weeks. Plasma total 25(OH)D concentration increased by 130% in the vitamin D₃ group and decreased by 43% in the placebo group (both P = 0.001). The percentage change of plasma cathelicidin concentration in the vitamin D₃ group was higher than in the placebo group (P = 0.025). Only in the vitamin D₃ group, the saliva SIgA and cathelicidin secretion rates increased over time (both P = 0.03). A daily 5000 IU vitamin D₃ supplement has a beneficial effect in up-regulating the expression of SIgA and cathelicidin in athletes during a winter training period, which could improve resistance to respiratory infections.     

Oral conjugated linoleic acid supplementation enhanced glycogen resynthesis in exercised human skeletal muscle

Present study examined the effects of conjugated linoleic acid (CLA) supplementation on glycogen resynthesis in exercised human skeletal muscle. Twelve male participants completed a cross-over trial with CLA (3.8 g/day for 8 week) or placebo supplements by separation of 8 weeks. CLA is a mixture of trans-10 cis-12 and cis-9 trans-11 isomers (50:50). On experiment day, all participants performed 60-min cycling exercise at 75% VO₂ max, then consumed a carbohydrate meal immediately after exercise and recovered for 3 h. Biopsied muscle samples from vastus lateralis were obtained immediately (0 h) and 3 h following exercise. Simultaneously, blood and gaseous samples were collected for every 30 min during 3-h recovery. Results showed significantly increased muscle glycogen content with CLA after a single bout of exercise (P < 0.05). Muscle glucose transporter type 4 expression was significantly elevated immediately after exercise, and this elevation was continued until 3 h after exercise in CLA trial. However, P-Akt/Akt ratio was not significantly altered, while glucose tolerance was impaired with CLA. Gaseous exchange data showed no beneficial effect of CLA on fat oxidation, instead lower non-esterified fatty acid and glycerol levels were found at 0 h. Our findings conclude that CLA supplementation can enhance the glycogen resynthesis rate in exercised human skeletal muscle.     

Changes in cytokines,leptin, and IGF-1 levels in overtrained athletes during a prolonged recovery phase: A case-control study

We investigated how cytokines are implicated with overtraining syndrome (OTS) in athletes during a prolonged period of recovery. Plasma IL-6, IL-10, TNF-α, IL-1β, adipokine leptin, and insulin like growth factor-1 (IGF-1) concentrations were measured in overtrained (OA: 5 men, 2 women) and healthy control athletes (CA: 5 men, 5 women) before and after exercise to volitional exhaustion. Measurements were conducted at baseline and after 6 and 12 months. Inflammatory cytokines did not differ between groups at rest. However, resting leptin concentration was lower in OA than CA at every measurement (P < 0.050) but was not affected by acute exercise. Although IL-6 and TNF-α concentrations increased with exercise in both groups (P < 0.050), pro-inflammatory IL-1β concentration increased only in OA (P < 0.050) and anti-inflammatory IL-10 was greater in CA (P < 0.001). In OA, exercise-related IL-6 and TNF-α induction was enhanced during the follow-up (P < 0.050). IGF-1 decreased with exercise in OA (P < 0.050); however, no differences in resting IGF-1 were observed. In conclusion, low leptin level at rest and a pro-inflammatory cytokine response to acute exercise may reflect a chronic maladaptation state in overtrained athletes. In contrast, the accentuation of IL-6 and TNF-α responses to acute exercise seemed to associate with the progression of recovery from overtraining.     

Effects of sodium phosphate and caffeine loading on repeated-sprint ability

The effects of sodium phosphate and caffeine supplementation were assessed on repeated-sprint ability. Using a randomised, double-blind, Latin-square design, 12 female, team-sport players participated in four trials: (1) sodium phosphate and caffeine, (2) sodium phosphate and placebo (for caffeine), (3) caffeine and placebo (for sodium phosphate) and (4) placebo (for sodium phosphate and caffeine), with ~21 days separating each trial. After each trial, participants performed a simulated team-game circuit (4 × 15 min quarters) with 6 × 20-m repeated-sprints performed once before (Set 1), at half-time (Set 2), and after end (Set 3). Total sprint times were faster after sodium phosphate and caffeine supplementation compared with placebo (Set 1: P = 0.003; Set 2: d = ?0.51; Set 3: P < 0.001; overall: P = 0.020), caffeine (Set 3: P = 0.004; overall: P = 0.033) and sodium phosphate (Set 3: d = ?0.67). Furthermore, total sprint times were faster after sodium phosphate supplementation compared with placebo (Set 1: d = ?0.52; Set 3: d = ?0.58). Best sprint results were faster after sodium phosphate and caffeine supplementation compared with placebo (Set 3: P = 0.007, d = ?0.90) and caffeine (Set 3: P = 0.024, d = ?0.73). Best sprint times were also faster after sodium phosphate supplementation compared with placebo (d = ?0.54 to ?0.61 for all sets). Sodium phosphate and combined sodium phosphate and caffeine loading improved repeated-sprint ability.     

Assessment of vitamin D concentration in non-supplemented professional athletes and healthy adults during the winter months in the UK: implications for skeletal muscle function

Abstract

The current study implemented a two-part design to (1) assess the vitamin D concentration of a large cohort of non-vitamin D supplemented UK-based athletes and 30 age-matched healthy non-athletes and (2) to examine the effects of 5000 IU · day^?1 vitamin D₃ supplementation for 8-weeks on musculoskeletal performance in a placebo controlled trial. Vitamin D concentration was determined as severely deficient if serum 25(OH)D < 12.5 nmol · l^?1, deficient 12.5–30 nmol · l^?1 and inadequate 30–50 nmol · l^?1. We demonstrate that 62% of the athletes (38/61) and 73% of the controls (22/30) exhibited serum total 25(OH)D < 50 nmol · l^?1. Additionally, vitamin D supplementation increased serum total 25(OH)D from baseline (mean ± SD = 29 ± 25 to 103 ± 25 nmol · l^?1, P = 0.0028), whereas the placebo showed no significant change (53 ± 29 to 74 ± 24 nmol · l^?1, P = 0.12). There was a significant increase in 10 m sprint times (P = 0.008) and vertical-jump (P = 0.008) in the vitamin D group whereas the placebo showed no change (P = 0.587 and P = 0.204 respectively). The current data supports previous findings that athletes living at Northerly latitudes (UK = 53° N) exhibit inadequate vitamin D concentrations (<50 nmol · l^?1). Additionally the data suggests that inadequate vitamin D concentration is detrimental to musculoskeletal performance in athletes. Future studies using larger athletic groups are now warranted.     

Influence of caffeine on perception of effort,metabolism and exercise performance following a high-fat meal

Abstract

This study examined the effects of caffeine, co-ingested with a high fat meal, on perceptual and metabolic responses during incremental (Experiment 1) and endurance (Experiment 2) exercise performance. Trained participants performed three constant-load cycling tests at approximately 73% of maximal oxygen uptake ([Vdot]O_2max) for 30 min at 20°C (Experiment 1, n = 8) and to the limit of tolerance at 10°C (Experiment 2, n = 10). The 30 min constant-load exercise in Experiment 1 was followed by incremental exercise (15 W · min^?1) to fatigue. Four hours before the first test, the participants consumed a 90% carbohydrate meal (control trial); in the remaining two tests, the participants consumed a 90% fat meal with (fat + caffeine trial) and without (fat-only trial) caffeine. Caffeine and placebo were randomly assigned and ingested 1 h before exercise. In both experiments, ratings of perceived leg exertion were significantly lower during the fat + caffeine than fat-only trial (Experiment 1: P < 0.001; Experiment 2: P < 0.01). Ratings of perceived breathlessness were significantly lower in Experiment 1 (P < 0.01) and heart rate higher in Experiment 2 (P < 0.001) on the fat + caffeine than fat-only trial. In the two experiments, oxygen uptake, ventilation, blood [glucose], [lactate] and plasma [glycerol] were significantly higher on the fat + caffeine than fat-only trial. In Experiment 2, plasma [free fatty acids], blood [pyruvate] and the [lactate]:[pyruvate] ratio were significantly higher on the fat + caffeine than fat-only trial. Time to exhaustion during incremental exercise (Experiment 1: control: 4.9, s = 1.8 min; fat-only: 5.0, s = 2.2 min; fat + caffeine: 5.0, s = 2.2 min; P > 0.05) and constant-load exercise (Experiment 2: control: 116 (88 – 145) min; fat-only: 122 (96 – 144) min; fat + caffeine: 127 (107 – 176) min; P > 0.05) was not different between the fat-only and fat + caffeine trials. In conclusion, while a number of metabolic responses were increased during exercise after caffeine ingestion, perception of effort was reduced and this may be attributed to the direct stimulatory effect of caffeine on the central nervous system. However, this caffeine-induced reduction in effort perception did not improve exercise performance.     

Individual differences in the interleukin-6 response to maximal and submaximal exercise tasks

Abstract

The inflammatory responsive cytokine interleukin-6 (IL-6) helps regulate immune responses to exercise. Evidence suggests that increases in IL-6 are related to exercise duration and intensity. However, the moderating effect of sex and underlying mediators have received limited attention. We compared plasma IL-6 responses to two cycling tasks with a resting control in young male (n = 12) and female (n = 12) recreationally active adults. Both 45 min tasks comprised an incremental test, either maximal or submaximal, followed by steady-state exercise at 55% peak power output. Interleukin-6 was elevated above baseline immediately after the maximal but not the submaximal task. Compared with the control condition, IL-6 was increased at 30 and 60 min after both exercise tasks. The IL-6 response was greater in women than men at 60 min after maximal exercise. Cortisol increased in both tasks compared with the control condition, the increase being greater after maximal than submaximal exercise. No associations were found between IL-6 responses and cortisol, heart rate, fitness or body mass index. The results show that 45 min of moderate-intensity exercise can increase IL-6 and suggest that the inclusion of maximal effort may accelerate this response. The finding that women showed a greater IL-6 response to maximal exercise may reflect a gender dimorphism in the immune response to stress.     

The effects of carbohydrate ingestion on the badminton serve after fatiguing exercise

Abstract

The badminton serve requires great skill and may be affected by fatigue. The aim of the present study was to determine whether carbohydrate ingestion affects badminton performance. Nine male badminton players (age 25 ± 7 years, mass 80.6 ± 8.0 kg) attended the laboratory on three occasions. The first visit involved an incremental exercise test to exhaustion to determine peak heart rate. Participants were given 1 L of a carbohydrate-electrolyte drink or a matched placebo during the experimental trials. The accuracy of 10 long and 10 short serves was determined before and after exercise. The fatiguing exercise was 33 min in duration (83 ± 10% and 84 ± 8% peak heart rate for the placebo and carbohydrate trial respectively). Capillary blood samples (20 μL) were taken before and after exercise for determination of blood glucose and lactate. There was deterioration in long serve accuracy with fatigue (P = 0.002), which carbohydrate ingestion had a tendency to prevent (P = 0.077). There was no effect of fatigue (P = 0.402) or carbohydrate ingestion (P = 0.109) on short serve accuracy. There was no difference in blood glucose concentration between trials (P = 0.851). Blood lactate concentration was higher during the placebo trial (P = 0.016). These results suggest that only the long serve is influenced by fatigue and carbohydrate had a tendency to prevent the deterioration in performance.     

Effect of cold water immersion on repeat cycling performance and thermoregulation in the heat

Abstract

To assess the effect of cold water immersion and active recovery on thermoregulation and repeat cycling performance in the heat, ten well-trained male cyclists completed five trials, each separated by one week. Each trial consisted of a 30-min exercise task, one of five 15-min recoveries (intermittent cold water immersion in 10°C, 15°C and 20°C water, continuous cold water immersion in 20°C water or active recovery), followed by 40 min passive recovery, before repeating the 30-min exercise task. Recovery strategy effectiveness was assessed via changes in total work in the second exercise task compared with that in the first. Following active recovery, a mean 4.1% (s = 1.8) less total work (P = 0.00) was completed in the second than in the first exercise task. However, no significant differences in total work were observed between any of the cold water immersion protocols. Core and skin temperature, blood lactate concentration, heart rate, rating of thermal sensation, and rating of perceived exertion were recorded. During both exercise tasks there were no significant differences in blood lactate concentration between interventions; however, following active recovery blood lactate concentration was significantly lower (P < 0.05; 2.0 ± 0.8 mmol · l^?1) compared with all cold water immersion protocols. All cold water immersion protocols were effective in reducing thermal strain and were more effective in maintaining subsequent high-intensity cycling performance than active recovery.     

Carbohydrate ingestion and soccer skill performance during prolonged intermittent exercise

Abstract

The aim of this study was to investigate the effect of ingesting a carbohydrate-electrolyte solution, during the 90-min Loughborough Intermittent Shuttle Test, on soccer skill performance. Seventeen male soccer players ingested either a 6.4% carbohydrate-electrolyte solution or placebo solution equivalent to 8 ml · kg^?1 body mass before exercise and 3 ml · kg^?1 body mass after every 15 min of exercise, in a double-blind randomized cross-over design, with the trials separated by 7 days. The evening before the main trial, the participants performed glycogen-reducing exercise on a cycle ergometer (80 min at 70%[Vdot]O_2max) and were then fed a low-carbohydrate meal. After a 12-h overnight fast, they performed The Loughborough Soccer Passing Test before and after every 15 min of exercise. Analysis of the combined skill test data showed a significant time effect (P = 0.001) with differences between 0–45 and 75–90 min (P < 0.05). There was a 3% reduction in skill performance from before to after exercise in the carbohydrate-electrolyte trial, whereas in the placebo trial the decrease was 14% (P = 0.07). In conclusion, skill performance during the simulated soccer activity appeared to deteriorate in the last 15–30 min of exercise. However, providing 52 g · h^?1 carbohydrate during exercise showed a tendency to better maintain soccer skill performance than a taste-matched placebo.     

Acute taurine supplementation enhances thermoregulation and endurance cycling performance in the heat

Abstract

This study investigated the effects of oral taurine supplementation on cycling time to exhaustion at a fixed-intensity and thermoregulation in the heat. In a double-blind, randomised crossover design, 11 healthy males participated in a time to exhaustion test in the heat (35°C, 40% RH), cycling at the power output associated with ventilatory threshold, 2?h after ingesting: Taurine (50?mg?kg^?1) or placebo (3?mg?kg^?1?maltodextrin). Core and mean skin temperature, mean sweat rate, heart rate, rating of perceived exertion (RPE), thermal comfort and thermal sensation were measured during exercise and blood lactate concentration (B[La]) was measured after exercise. Taurine supplementation increased time to exhaustion by 10% (25.16 min vs. 22.43 min, p?=?0.040), end sweat rate by 12.7% (687?nL?min^?1 vs. 600?nL?min^?1, p?=?0.034) and decreased B[La] by 16.5% (5.75?mmol?L^?1 vs. 6.85?mmol?L^?1, p?=?0.033). Core temperature was lower in the final 10% of the time to exhaustion (38.5°C vs. 38.1°C, p?=?0.049). Taurine supplementation increased time to exhaustion and local sweating, while decreasing RPE and core temperature in the later stages of exercise, as well as reducing post-exercise B[La]. This study provides the evidence of taurine's role in thermoregulatory processes. These findings have implications for the short-term preparation strategies of individuals exercising in the heat. Based on these findings, a single dose of taurine 2?h prior to training or competition would provide an ergogenic and thermoregulatory effect.     

Caffeine ingestion enhances perceptual responses during intermittent exercise in female team-game players

We examined the influence of caffeine supplementation on cognitive performance and perceptual responses in female team-game players taking low-dose monophasic oral contraceptives of the same hormonal composition. Ten females (24 ± 4 years; 59.7 ± 3.5 kg body mass; 2–6 training sessions per week) took part in a randomised, double-blind, placebo-controlled crossover-design trial. A 90-min intermittent treadmill-running protocol was completed 60 min following ingestion of a capsule containing either 6 mg ? kg^?1 anhydrous caffeine or artificial sweetener (placebo). Perceptual responses (ratings of perceived exertion (RPE), feeling scale (FS), felt arousal scale (FAS)), mood (profile of mood states (POMS)) and cognitive performance (Stroop test, choice reaction time (CRT)) were completed before, during and after the exercise protocol, as well as after ~12 h post exercise. Caffeine ingestion significantly enhanced the ratings of pleasure (P = 0.008) and arousal (P = 0.002) during the exercise protocol, as well as increased vigour (POMS; P = 0.007), while there was a tendency for reduced fatigue (POMS; P = 0.068). Caffeine ingestion showed a tendency to decrease RPE (P = 0.068) and improve reaction times in the Stroop (P = 0.072) and CRT (P = 0.087) tests. Caffeine supplementation showed a positive effect on perceptual parameters by increasing vigour and a tendency to decrease fatigue during intermittent running activity in female games players taking low-dose monophasic oral contraceptive steroids (OCS).     

Effects of training on spleen and peritoneal exudate reactive oxygen species and lymphocyte proliferation by splenocytes at rest and after an acute bout of exercise

Abstract

The purpose of this study was to analyse the effect of regular exercise on spleen and peritoneal exudate reactive oxygen species (ROS) and lymphocyte proliferation by splenocytes. Twenty-four female BALB/c mice were randomly divided into trained (n = 12) and untrained (n = 12) groups. These two groups were further divided into mice that were studied at rest (trained/rest, n = 5; untrained/rest, n = 6) and immediately after a 2 h acute bout of exercise (trained/exercise, n = 6; untrained/exercise, n = 6). The animals were bred in the animal facility of the Yonsei University College of Medicine, where they were housed in a temperature- (22 – 24°C) and humidity- (50 – 60%) controlled environment, with a 12 h photoperiod, and provided with food and water ad libitum. The trained mice underwent 10 weeks of endurance swimming training (5 days per week) in water at 26 – 29°C for 60 min. Changes in body mass, proliferative activity and the production of reactive oxygen species from spleen lymphocytes and peritoneal exudate cells were determined. The splenic lymphocytes of the trained mice had much greater proliferative activity than those of the untrained mice (P < 0.05). Trained mice had lower ROS production in splenic lymphocytes and peritoneal exudate cells than untrained mice. In both groups, there was substantial inhibition of proliferative activity stimulated with medium, concanavalin A and lipopolysaccharide following the acute bout of exercise. This may have been caused by excessive ROS production following the acute exercise session.