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The SARS‐CoV‐2 pandemic may negatively impact mood and emotion. Physical activity may protect against mood disturbance and promote positive affect. This study asked if physical activity before, during, or the change in physical activity with the pandemic, impacted affect and mood during the pandemic. US adult residents (18–74 years; N = 338) were surveyed from 29 April to 3 June 2020. Physical activity before and during the pandemic was assessed with the Physical Activity Rating survey. The Positive and Negative Affect Schedule measured affect and the Profile of Moods Questionnaire assessed mood. Comparisons between physically inactive and active participants by Analysis of Covariance found greater vigour in participants classed as physically active before the pandemic. Positive affect, vigour and esteem‐related affect were greater in participants physically active during the pandemic. Multiple linear regression revealed relationships between the change in physical activity and mood. Change in physical activity positively associated with positive affect (b = 1.06), esteem‐related affect (b = 0.33) and vigour (b = 0.53), and negatively associated with negative affect (b = −0.47), total mood disturbance (b = −2.60), tension (b = −0.31), anger (b = −0.24), fatigue (b = −0.54), depression (b = −0.50) and confusion (b = −0.23). These data demonstrate that physical activity during the pandemic, and increased physical activity relative to before the pandemic, related to better mood.

Neuromuscular function is one of the important factors affecting athletic performance. Previous studies have shown that fish oil supplementation can improve performance. This study investigated the effect of fish oil on neuromuscular performance after exhausting exercise. Eighteen healthy men (mean ± standard deviation; age 26.9±2.6 years; weight 78.33±10.42 kg; height 175.8±4.9 cm; body fat percentage 18.40±5.46%) voluntarily participated and were randomly assigned to fish and corn oil groups in a double blind manner. Participants received 6 g/day of oil for 4 weeks, while maintaining baseline diet and training status during the study. Changes in maximal voluntary contraction (MVC) of the tibialis anterior muscle, neuromuscular propagation of tibialis anterior muscle (M-wave), corticospinal excitability (MEP: motor evoked potential), and the rate of perceived exertion (RPE) were evaluated before and after supplementation in response to a modified Bruce exhausting protocol. Group differences in changes in each variable following supplementation were assessed by two-way analysis of variances (ANOVA). Compared to corn oil, fish oil demonstrated less perceived exertion at the end of exhaustive exercise (F=9.72, P=0.001) after supplementation, and normalised MEP to M-wave showed a trend (F=3.83, P=0.071). However, M-wave peak to peak amplitudes changes were not significant between the groups (P>0.05). In addition, significant differences were observed between baseline MVC values of the group following supplementation. Thus, it seems that fish oil can improve corticospinal excitability, thereby improving neuromuscular function in exhausting activities. Therefore, fish oil supplementation may be recommended to increase performance in activities otherwise limited. However, the mechanism underlying this effect remains to be elucidated.

The adoptive transfer of donor-derived virus-specific T cells (VSTs) is an effective treatment for infections following allogeneic hematopoietic cell transplantation. Acute exercise mobilizes effector lymphocytes and VSTs to the circulation and augments the ex vivo manufacture of VSTs. This study determined if β(2) adrenergic receptor (AR) signaling precipitated the VST response to acute exercise. Healthy participants (n = 12) completed 30 min of steady-state cycling exercise after ingesting a placebo, a β(1 + 2) AR antagonist (nadolol) or a β(1) AR antagonist (bisoprolol). Circulating VSTs to cytomegalovirus (CMV), Epstein–Barr virus (EBV), and adenovirus (AdV) antigens were enumerated before and after exercise, and peripheral blood mononuclear cells were cultured with viral peptides for 8 days to expand multi-VSTs. Compared with placebo, nadolol blunted the exercise-induced mobilization of CMV-VSTs (Δ VSTs/100,000 CD3(+) T cells = 93 ± 104 vs. 22 ± 91 for placebo and nadolol, respectively; p = 0.036), while bisoprolol did not, despite both drugs evoking similar reductions in exercising heart rate and blood pressure. Circulating AdV and EBV VSTs (VSTs/mL blood) only increased after exercise with placebo. Although not significant, nadolol partially mitigated exercise-induced increases in multi-VST expansion, particularly in participants that demonstrated an exercise-induced increase in VST expansion. We conclude that exercise-induced enhancements in VST mobilization and expansion are at least partially β(2) AR mediated, thus highlighting a role for the β(2) AR in targeted therapy for the augmentation of VST immune cell therapeutics in the allogeneic adoptive transfer setting. Moreover, long-term regular exercise may provide additional viral protection in the host through frequent β(2) AR-dependent mobilization and redistribution of VSTs cumulated with each bout of exercise.

Purpose The nodlike receptor family pyrin domain containing 3 (NLRP3) inflammasome is a critical player in vascular pathology as it regulates caspase-1-mediated interleukin (IL)-1β processing. Physical activity ameliorates obesity-induced inflammation and vascular dysfunction, but the mechanisms responsible for these positive changes are incompletely understood. Here, the protective effect of physical activity on the inflammasome-associated vascular dysfunction in obesity and its putative mechanisms were investigated. Methods Mice were fed a control low-fat diet (LFD) or a high-fat diet (HFD; 45% of calories from fat) and provided with running wheel access (LF-RUN or HF-RUN) or denied wheel access for our sedentary condition (LF-SED or HF-SED). The NLRP3 inflammasome-associated pathway, including NLRP3, caspase-1, and IL-1β, in mice aorta was examined by RT-qPCR and FLICA and DAB staining. The protein expression of zonula occluden-1 (ZO-1), ZO-2, adiponectin (APN), and adiponectin receptor 1 (AdipoR1) in aortic endothelial cells was determined by immunofluorescence double staining. Intracellular reactive oxidative stress and nitric oxide (NO) production were monitored with fluorescence probes, dihydroethidium, and diaminofluorecein. Results HFD increased caspase-1 and IL-1β at mRNA and protein levels in endothelial cells of the aorta, and this was attenuated by voluntary running. HFD decreased ZO-1 and ZO-2 expression and reduced APN and AdipoR1 signaling; these were restored by running. The elevated intracellular superoxide (O2) production observed in HF-SED was ameliorated in HF-RUN. Finally, HF-RUN improved NO production in the aorta compared with HF-SED. Conclusions Our findings suggest that voluntary running ameliorates mechanisms associated with vascular dysfunction by suppressing NLRP3 inflammasome, improving NO production, and reducing oxidative stress. Such benefits of physical activity may be, at least in part, associated with APN-AdipoR1 signaling and tight junction protein expression.

The paleo diet is popular among the general population due to promoted weight loss and disease prevention benefits. We examined the effectiveness of a self-administered paleo diet in improving cardiometabolic disease risk factors. Overweight, physically inactive but otherwise healthy adults (males = 4, females = 3, age 32.7 ± 4.9 years, body mass index [BMI] 29.4 ± 2.4 kg/m2) habitually eating a traditional Western diet (1853.4 ± 441.2 kcal; 34.0% carbohydrate; 41.4% fat; 19.2% protein) completed an ad libitum self-administered paleo diet for 8 weeks. Height, weight, blood pressure, and a fasting blood sample were collected pre– and post–paleo dietary intervention. Blood samples were analyzed for fasting cardiometabolic disease biomarkers—including brain-derived neurotropic factor (BDNF), fibroblast growth factor (FGF) 21, and leptin. After 8 weeks, body mass (−5.3 kg, P = .008), BMI (−1.7 kg/m2, P = .002), serum leptin (−56.2%, P = .012), serum FGF21 (−26.7%, P = .002), and serum BDNF (−25.8%, P = .045) significantly decreased. Systolic and diastolic blood pressure were unchanged following the paleo dietary intervention ( P > .05). Average energy intake (−412.6 kcal, P = .016) significantly decreased with the paleo dietary intervention mostly due to a reduction in carbohydrate consumption (−69.2 g; P = .003). An 8-week self-administered paleo dietary intervention was effective in improving cardiometabolic disease risk factors in a healthy, physically inactive overweight adult population.

Exercise can lower the risk of developing pancreatic cancer and has the potential to improve physical fitness and quality of life in patients with the disease. Yet, the effects of exercise training during pancreatic cancer treatment remain poorly characterized. This hampers the development of evidence-based disease-specific exercise recommendations.The purpose of this review was to describe and interpret the effect of exercise on physiological, QoL, and cancer-specific outcomes reported in clinical trials among pancreatic cancer patients during treatment.We conducted a scoping review of the literature according to the framework proposed by Arksey and O'Malley. Articles published prior to December 2021 were retrieved from PubMed, EMBASE, and Scopus. We only included studies that prescribed structured cardiorespiratory and/or resistance exercise in pancreatic cancer patients undergoing treatment.A total of 662 references were retrieved, of which 24 are included in the review. Twelve articles were randomized controlled trials and 12 were single-arm trials. Overlap in the trials from which data were reported occurred in 16 articles. Moderate intensity exercise was most commonly prescribed, reported feasible for most patients, with potential to enhance physical fitness and QoL. However, exercise adherence and beneficial effects may diminish with disease progression. Limited evidence suggests exercise may benefit cancer-specific outcomes.The results of this review indicate that exercise is feasible during pancreatic cancer treatment. Exercise can also improve physical fitness and QoL. However, its beneficial effects may fall with advanced disease and more rigorous research is needed to develop precise exercise protocols for this population.

Aging is associated with many chronic diseases that are maintained and perpetuated by immune dysregulation and chronic systemic inflammation. T-cells often undergo age-related changes, including an accumulation of memory cells, which places individuals at increased risk for novel infections and may predispose them to increased inflammation. Regular exercise training has been suggested to offset age-related changes in T-cells, but the majority of literature is derived from cardiorespiratory exercise (CRE) studies. Much less is understood about the T-cell response to resistance exercise (RE). The purpose of this study was to examine the effects of acute CRE and acute RE on the T-cell response among a cohort of physically active older adults (PA) compared to a cohort of physically inactive older adults (PI).METHODSTwenty-four healthy older adults (PA n=12; PI n=12; mean ± SD; age (yrs) PA 62 ± 5, PI 64 ± 5; height (cm) PA 170.9 ± 6.9, PI 162.9 ± 8.0; weight (kg) PA 69.3 ± 10.2, PI 68.2 ± 12.8; BMI (kg/m2) PA 23.9 ± 3.0, PI 25.6 ± 3.5) completed one bout of CRE and one bout of RE in a randomized order, both at a moderate intensity, and separated by at least 7 days. Blood samples drawn pre-exercise, post-exercise, and 1h post-exercise (recovery) were analyzed for CD4+ and CD8+ T-cells and their differentiation status using surface markers CD45RA, CD62L, and CD57, as well as for Th17 cells (CD4+ CD161+ CD196+) using flow cytometry.RESULTSPI had higher numbers of circulating CD57+ EMRA CD4+ T-cells (PA, mean ± SE, 1 ± 2 cells/uL; PI, 6 ± 2 cells/uL; p=0.01; z=2.32) than PA at pre-exercise. Both CRE and RE elicited a significant mobilization of highly-differentiated (CD45RA+ CD62L-; CD57+ CD45RA+ CD62L-) CD8+ T-cells into the circulation post-exercise in both PA and PI groups. Furthermore, CRE resulted in a decrease in the number of circulating Th17 cells post-exercise, while RE increased Th17 cell mobilization compared to the CRE response.CONCLUSIONTaken together, T-cells in PA and PI respond similarly to acute CRE and support previously reported data showing a significant mobilization of highly differentiated T-cells. The present study confirms that moderate intensity RE also elicits this response, but highlights potential differences between CRE and RE on the immune responses of T-cells, particularly in PI individuals.Clinical trial registrationThis research study was registered at clinicaltrials.gov NCT03794050

The Paleolithic diet, characterized by an emphasis on hunter-gatherer type foods accompanied by an exclusion of grains, dairy products, and highly processed food items, is often promoted for weight loss and a reduction in cardiometabolic disease risk factors. Specific adipokines, such as adiponectin, omentin, nesfatin, and vaspin are reported to be dysregulated with obesity and may respond favorably to diet-induced fat loss. We aimed to evaluate the effects of an eight-week Paleolithic dietary intervention on circulating adiponectin, omentin, nesfatin, and vaspin in a cohort of physically inactive, but otherwise healthy adults. Methods: Seven inactive adults participated in eight weeks of adherence to the Paleolithic Diet. Fasting blood samples, anthropometric, and body composition data were collected from each participant pre-and post-intervention. Serum adiponectin, omentin, nesfatin, and vaspin were measured. Results: After eight weeks of following the Paleolithic diet, there were reductions (p0.05), while serum vaspin levels for all participants were undetectable. Conclusions: It is possible that although eight weeks resulted in modest body composition changes, short-term fat loss will not induce changes in adiponectin, omentin, and nesfatin in apparently healthy adults. Larger, long-term intervention studies that examine Paleolithic diet-induced changes across sex, body composition, and in populations with metabolic dysregulation are warranted.

In the United States, overweight/obesity is more prevalent among those with low-income, higher income is related to greater leisure time physical activity (LTPA) and sedentary behavior (SB), which are inversely related to overweight/obesity. This study aimed to evaluate the role of LTPA and SB simultaneously in the income-overweight/obesity relationship. Cross-sectional data from the National Health and Nutrition Examination Survey (2007–2014) were utilized (n = 10,348 non-older adults (aged 20–59 years)). A multiple mediator structural equation model was conducted to evaluate the indirect effects from income to overweight/obesity (Body Mass Index ≥25 kg/m2) through LTPA and SB simultaneously, controlling for confounding variables, including diet, smoking, and alcohol consumption. As expected, greater income was negatively associated with overweight/obesity. Income indirectly influenced overweight/obesity through LTPA (Indirect effect: B = −0.005, CI = −0.01, −0.003), and through SB (Indirect effect: B = 0.008, CI = 0.005, 0.01), in opposing directions. The direct effect from income to overweight/obesity remained statistically significant. LTPA partially accounted for the negative relationship between income and overweight/obesity, SB reduced the strength of the negative relationship between income and overweight/obesity. Targeted behavior approaches for weight management may be beneficial. Increasing LTPA among adults with lower income and decreasing SB among adults with higher income may provide some overweight/obesity protection.

Older adults are at elevated risk for morbidity and mortality caused by influenza. Vaccination is the primary means of prophylaxis, but protection is often compromised in older adults. As acute eccentric resistance exercise mobilizes immune cells into muscle, it may enhance vaccination response. PURPOSE: Compare antibody responses to influenza vaccination in older adults who performed resistance exercise prior to vaccination to those who did not exercise. METHODS: 29 resistance training-naive older adults (20 women, 73.9 ± 5.3 years) were randomized to 1 of 3 groups: vaccination in the same arm that exercised (Ex-S), vaccination in the opposite arm that exercised (Ex-OP), and seated rest (No-Ex). Exercise was unilateral and consisted of 10 sets of 5 eccentric repetitions at 80% of the pre-determined concentric one repetition maximum. Lateral raises were alternated with bicep curls. No-Ex sat quietly for 25 min. Following exercise or rest, all subjects received the 2018 quadrivalent influenza vaccine (Seqirus Afluria) in the non-dominant deltoid. Antibody titers against the four influenza vaccine strains were determined by hemagglutinin inhibition assays at baseline, 6-, and 24-weeks post-vaccination. Group differences in antibody titers by time were assessed by restricted maximum likelihood mixed models. Fold-changes in antibody titers 6- and 24-weeks from baseline were compared between groups by Kruskal-Wallis tests. RESULTS: No significant group x time effects were found for any strain. Groups did not differ in fold-increase of antibody titers 6- and 24-weeks post-vaccination. Although seroconversion rates remained low, only one subject (Ex-S) reported flu-like symptoms 18 weeks post-vaccination. CONCLUSION: Acute arm eccentric exercise did not influence antibody titers to the influenza vaccine delivered post-exercise in older adults. More strenuous exercise may be required for exercise to act as an adjuvant. http://ClinicalTrials.gov Identifier: NCT03736759 U.S. NIH Grant/Contract: R03AG052778

Insufficient sleep during childhood can lead to physical and mental health issues. In adults, sleep disturbances have been associated with altered levels of stress hormones and inflammatory cytokines, but data in youth is lacking. The aim of this study was to explore relationships between objective measures of sleep and salivary biomarkers in children and adolescents. Participants (N = 55, aged 8–16 years, 53% female) wore an actigraph sleep monitor in their home for seven nights and completed sleep diaries and the School Sleep Habits Survey (SSHS). Participants also donated first waking saliva samples, which were later assayed for α-amylase (sAA), cortisol, interleukin (IL)-6, and IL-1β. While sAA was not associated with objective sleep it did show a positive association with self-reported sleep disturbance. Morning cortisol levels were associated with objective sleep variables, including minutes spent awake the night before sampling, and sleep efficiency and awakenings the night after sampling. Morning IL-6 was associated with prior night sleep efficiency and minutes spent awake the night after saliva sampling. Likewise, IL-1β levels were associated with sleep duration and sleep onset latency during the nighttime sleep period prior to and after saliva sampling. These results align with other data to indicate objective elements of sleep are related to salivary cortisol, IL-6, and IL-1β in youth. Thus, quality of sleep on the night prior to sampling should be considered when investigating levels of salivary mediators in children.

Acute exercise preferentially mobilizes cytotoxic T-cells, NK-cells and non-classical monocytes to the bloodstream under the influence of hemodynamic forces and/or β2-adrenergic receptor (β2-AR) signaling. However, the relative contribution of these mechanisms to the redeployment of the most exercise-responsive cell types is largely unknown. We determined the lymphocyte and monocyte subtypes mobilized to blood during exercise via β2-AR signaling whilst controlling for β1-AR mediated reductions in hemodynamic forces. In a randomized, double blind, complete cross-over design, 14 healthy cyclists exercised for 30-minutes at +10% of blood lactate threshold after ingesting: (1) a placebo, (2) a β1-preferential antagonist (10 mg bisoprolol), or (2) a non-preferential β1 + β2-antagonist (80 mg nadolol) across three trials separated by >7-days. Bisoprolol was administered to reduce hemodynamic forces (heart rate and blood pressure) during exercise to levels comparable with nadolol but without blocking β2-ARs. The mobilization of total NK-cells, terminally differentiated (CD57+) NK-cells, central memory, effector memory and CD45RA+ effector memory CD8+ T-cells; non-classical monocytes; and γδ T-cells were significantly blunted or abrogated under nadolol compared to both bisoprolol and placebo, indicating that the exercise-induced mobilization of these cell types to the blood is largely influenced by β2-AR signaling. Nadolol failed to inhibit the mobilization of classical monocytes, CD4+ T-cells (and their subsets) or naive CD8+ T-cells, indicating that these cell types are mobilized with exercise independently of the β2-AR. We conclude that the preferential mobilization of NK-cells, non-classical monocytes and differentiated subsets of CD8+ T-cells with exercise is largely dependent on catecholamine signaling through the β2-AR. These findings provide mechanistic insights by which distinct lymphocyte and monocyte subtypes are preferentially mobilized to protect the host from anticipated injury or infection in response to an acute stress response.

Exercise has been proposed as a treatment for several psychiatric disorders. Exercise may act in part through beneficial effects on reward functioning, as it alters neurotransmitter levels in reward-related circuits. However, there has been little investigation of the effect of exercise on reward functions in humans. We hypothesized an acute bout of exercise would increase motivation for and pleasurable responses to rewards in healthy humans. In addition, we examined possible moderators of exercise's effects, including demographics, fitness and previous exercise experience. Thirty-five participants completed exercise and sedentary control sessions in randomized, counterbalanced order on separate days. Immediately after each activity, participants completed measures of motivation for and pleasurable responses to rewards, consisting of willingness to exert effort for monetary rewards and subjective responses to emotional pictures. Exercise did not increase motivation or pleasurable responses on average. However, individuals who had been running for more years showed increases in motivation for rewards after exercise, while individuals with less years running showed decreases. Further, individuals with higher resting heart rate variability reported lower arousal in response to all emotional pictures after exercise, while individuals with low heart rate variability reported increased arousal in response to all emotional pictures after exercise. General fitness did not have similar moderating effects. In conclusion, acute exercise improved reward functioning only in individuals accustomed to that type of exercise. This suggests a possible conditioned effect of exercise on reward functioning. Previous experience with the exercise used should be examined as a possible moderator in exercise treatment trials.

Purpose: To investigate the T-lymphocyte response to a period of increased training volume in trained females compared to habitual activity in female controls. Methods:Thirteen trained female (19.8±1.9yrs) soccer players were monitored during a two-week long high volume training period (increased by 39%) and thirteen female untrained (20.5±2.2yrs) controls were monitored during two-weeks of habitual activity. Blood lymphocytes, collected at rest, were isolated before and after the two-week period. Isolated lymphocytes were assessed for the cell surface expression of the co-receptor CD28, a marker of T-lymphocyte naivety, and CD57 a marker used to identify highly-differentiated T-lymphocytes. Co-expression of these markers was identified on helper CD4+and cytotoxic CD8+ T-lymphocytes. In addition a further population of γδ+T-lymphocytes were identified. Plasma was used to determine Cytomegalovirus (CMV) serostatus. Results: No difference was observed in the T-lymphocyte populations following the two-week period of increased volume training. At baseline the number of total CD3+, cytotoxic CD8+, naïve (CD8+CD28+CD57−), intermediate (CD8+CD28+CD57+) T-lymphocytes and the number and proportion of γδ+T-lymphocytes were greater in the trained compared to the untrained females (p

Infection with adenovirus 36 (Ad36) has been associated with risk of obesity in youth in some studies, but the seroprevalence of this virus has not been examined among all populations. As Hispanic-American youth are of greater risk for obesity than other American youth, we sought to determine the proportion of Ad36 seropositive (Ad36+) students in an urban middle school serving a Hispanic population. We further examined if Ad36+ students were more likely to have obesity, and if Ad36 serostatus impacted changes in weight status following a health intervention. We determined body mass index (BMI) at the beginning and end of a 16-week health intervention among 40 Hispanic-American middle-school students. Ad36 serostatus was determined by enzyme-linked immunsorbent assay (ELISA). Seventy percent of the students were Ad36+. Ad36+ and Ad36 seronegative (Ad36−) did not differ before or after the intervention in body weight measures. The odds of being classified as obese was 1.4 times greater among Ad36+ than Ad36− at baseline, and 2.4 times greater post-intervention, but these were not statistically significant. We report a high seroprevalence of Ad36 among a population of Hispanic-American students. Ad36 seropositivity was associated with a trend for a greater likelihood of having obesity, but did not impact response to a health intervention.

Acute exercise preferentially mobilizes cytotoxic T-cells, NK-cells and non-classical monocytes to the bloodstream under the influence of hemodynamic forces and/or β

Acute exercise evokes an almost instantaneous lymphocytosis, followed by sustained lymphopenia that occurs within just 30–60 min after exercise cessation. The aim of this study was to characterize the immediate (order of minutes) post-exercise kinetics of lymphocyte and monocyte egress, and to determine whether this egress is associated with heart rate recovery following a single bout of steady state dynamic exercise. Eleven healthy subjects cycled for 30-min at ~70% of their estimated peak power. Blood samples were collected from an intravenous catheter before exercise, during exercise (E) at +15 and +30 min, and during passive recovery (R) at exactly +1, +2, +3, +4, +5 and +10 min after exercise cessation. Complete blood counts and flow cytometry were used to enumerate total monocytes, lymphocytes: CD3+ T-cells, CD4+ T-cells, CD8+ T-cells, NK-cells and γδ T-cells in whole blood. Both lymphocytes and monocytes displayed rapid egress kinetics, by R+3 the total numbers of all cell types examined were significantly lower than E+30. NK-cells egressed more rapidly than other lymphocyte subtypes, followed by CD8+, γδ, and then CD4+ T-cells. Further, the egress of NK-cells, CD4+, and CD8+ T-cells positively correlated with heart rate recovery after exercise cessation. In conclusion, lymphocyte and monocyte egress is rapid and occurs within minutes of exercise recovery, underscoring both the importance of collection time for post exercise blood samples, and the use of intravenous catheters to capture peak cell mobilization. The rate of egress may be dependent on how quickly hemodynamic equilibrium is restored on cessation of exercise and is, therefore, likely to be influenced by individual fitness levels.

The beginning of a lifestyle intervention is a sensitive time, as doing “too much too quickly” may stress the immune system, resulting in an increase in upper respiratory symptoms and, consequently, attrition. However, “too little too slowly” may not align with patients’ motivation to change and may also result in attrition. There is also evidence that early weight loss is predictive of long-term maintenance of goal weight. Health care providers are frequently presented with contradictory information on the best model to promote enduring lifestyle change. Best practice dictates that health care provider acknowledge their patients’ motivation to change and incorporate each individual’s goals in designing the lifestyle change intervention. Additional support and advice may be warranted at the beginning of an intervention to promote the patient’s health and avoid attrition.

Natural Killer cells are cytotoxic lymphocytes that recognize and eliminate tumor cells. Exercise enhances NK cell cytotoxic activity (NKCA), yet the underlying mechanisms are not fully understood. Exercise-induced shifts in NK-cell subsets has been proposed as one mechanism. Alternatively, exercise alters stress hormone and cytokine levels, which are also known to affect NKCA. AIM: Determine the role(s) of exercise-induced shifts in the proportions of NK-cell subsets found in the blood, and changes in serum IL-2, IL-6, IL-12, IFN-γ, TNF-α and cortisol, on exercise-induced changes in NKCA. METHODS: Twelve adults cycled 30 min at 115% of their lactate threshold power. Peripheral blood mononuclear cells (PBMCs) and serum were isolated from blood collected pre-, post-, and 1 h post-exercise. To investigate the effect of shifts in NK-cell subsets, pre-, post- and 1 h post-exercise NK cells were incubated with target cells (K562 and U266) in the presence of autologous pre-exercise serum. The effects of hormones and cytokines released during exercise were determined by incubating pre-exercise PBMCs with tumor target cells (K562 and U266) in the presence of pre-, post-, and 1 h post-exercise serum. NKCA and phenotypes were assessed by flow cytometry. RESULTS: Although exercise mobilized high-differentiated NK cell subsets (NKG2A-/KIR+), NKCA per cell was not altered post-exercise in the presence of pre-exercise serum. Conversely, 1 h post-exercise serum significantly increased the cytotoxicity of pre-exercise NK cells against HLA-expressing target cells (U266). This increase associated with lower levels of cortisol, and occurred when serum contained higher levels of IFN-γ. CONCLUSIONS: Exercise-induced shifts in NK-cell subsets did not fully explain changes in NKCA. Rather, factors present in serum during exercise recovery enhanced NKCA against target cells. Our results suggest lower cortisol and higher IFN-γ levels may explain exercise-induced changes in NKCA.

Exercise is thought to exert beneficial effects on reward functioning, as it alters neurotransmitter levels in reward-related circuits. However, there has been little investigation of the effect of exercise on reward functions in humans. We hypothesized a bout of exercise would increase motivation for and pleasurable responses to rewards in healthy adults. We also examined possible moderators of exercise’s effects. Thirty-five participants completed exercise (20 min run at 105% of lactate threshold intensity) and rest (20 min sit) sessions in a randomized, counterbalanced order. After each activity, participants completed measures of motivation for (Effort Expenditure for Rewards Task) and pleasurable responses to (International Affective Picture System Task) rewards. Exercise did not increase motivation for or pleasurable responses to rewards on average. However, there was a moderating effect of years running, as individuals who had been runners for more years showed increased motivation for rewards after exercise, while individuals with less years running showed decreases. Further, baseline heart rate variability negatively correlated with the effects of exercise on arousal. As this was not specific to picture type, it suggests a dysregulation of emotional responses after exercise in individuals with low HRV. Our results indicate that baseline characteristics may have important moderating influences on the effect of exercise on emotional functioning. Previous experience with the exercise used should be examined as a possible moderator in exercise interventions.

The magnitude of lymphocytosis following exercise is directly related to exercise intensity. Infection with cytomegalovirus (CMV) also augments lymphocytosis after exercise. It is not known if the enhanced T‐cell response to exercise due to CMV depends on exercise intensity. Furthermore, exercise‐induced changes in T‐cell expression of type I and type II cytokines are thought to be intensity dependent, but direct comparisons are lacking. The aim of this experiment was to determine if CMV affects the exercise‐induced redistribution of T‐cell subsets at varying intensities, and determine the effect of exercise intensity on CD8+ T‐cell cytokine expression. Seventeen cyclists (nine CMV seropositive; CMV+) completed three 30 min cycling trials at −5, +5, and +15% of blood lactate threshold (LT). T‐cell subsets in blood and intracellular expression of type I (IL‐2, interferon(IFN)‐γ) and type II (IL‐4, IL‐10) cytokines by CD8+ T cells pre, post, and 1‐h post‐exercise were assessed by flow cytometry. Independently of CMV, T‐cell subset redistribution was greater after +15%LT compared to −5%LT (P

Activation of the nucleotide‐binding oligomerization domain‐like receptor family pyrin domain‐containing 3 (NLRP3) inflammasome mediates the release of pro‐inflammatory cytokine interleukin (IL)‐1β and thereby plays a pivotal role in the inflammatory response in vascular pathology. An active lifestyle has beneficial effects on inflammation‐associated vascular dysfunction in obesity. However, it remains unclear how physical activity regulates NLRP3 inflammasome‐mediated vascular dysfunction in obesity. Therefore, we explored the protective effect of physical activity on NLRP3 inflammasome‐associated vascular dysfunction in mouse hearts, and the potential underlying mechanisms. C57BL/6J male mice were randomly divided into four groups: (1) control low‐fat diet (LF‐SED), (2) LF diet with free access to a voluntary running wheel (LF‐RUN), (3) high‐fat diet (HF‐SED; 45% of calories from fat), and (4) HF‐RUN. We examined NLRP3 inflammasome‐related signaling pathways, nitric oxide (NO) signaling, and oxidative stress in coronary arterioles to test effects of HFD and physical activity. Voluntary running reduced NLRP3 inflammasome and its downstream effects, caspase‐1 and IL‐1β in coronary arteriole endothelium of obese mice in immunofluorescence staining. HF‐RUN attenuated HFD‐dependent endothelial NO synthase (eNOS) reduction and thus increased NO production compared to HF‐SED. HFD elevated intracellular superoxide production in coronary arterioles while voluntary running ameliorated oxidative stress. Our findings provide the first evidence that voluntary running attenuates endothelial NLRP3 inflammasome activation in coronary arterioles of HFD feeding mice. Results further suggest that voluntary running improves obesity‐induced vascular dysfunction by preserved NO bioavailability via restored expression of eNOS and reduced oxidative stress.

The ex vivo generation of monocyte-derived-dendritic cells (mo-DCs) has facilitated the use of DCs in immunotherapy research. However, low blood monocyte numbers frequently limit the manufacture of sufficient numbers of mo-DCs for subsequent experimental and clinical procedures. Because exercise mobilizes monocytes to the blood, we tested if acute dynamic exercise by healthy adults would augment the generation of mo-DCs without compromising their differentiation or function. We compared mo-DC generation from before- and after-exercise blood over 8-days of culture. Function was assessed by FITC-dextran uptake and the stimulation of autologous cytomegalovirus (pp65)-specific-T-cells. Supporting the hypothesis, we found a near fourfold increase in number of mo-DCs generated after-exercise. Furthermore, relative FITC-dextran uptake, differentiation rate, and stimulation of pp65-specific-T-cells did not differ between before- and after-exercise mo-DCs. We conclude that exercise enhances the ex vivo generation of mo-DCs without compromising their function, and so may overcome some limitations associated with manufacturing these cells for immunotherapy.

The adoptive transfer of viral-specific T-cells (VSTs) is highly effective in treating viral infections after allogeneic hematopoietic stem cell transplant. Unfortunately, adoptive T-cell therapy is not available for a large number of patients due to logistical constraints associated with isolating and manufacturing enough VSTs from healthy donors. We have shown that a single exercise bout reliably augments the ex vivoexpansion of VSTs and thus might be useful as a clinical adjuvant to boost the manufacture of VSTs from healthy donors. We sought to determine if the augmenting effects of exercise on VST expansion are dependent on β2 adrenergic receptor (β2AR) signaling. Using a randomized cross-over and double-blinded design, ten subjects performed 30-min of steady state cycling exercise 3 h after ingesting (i) a placebo, (ii) a β1 + 2AR antagonist (nadolol), or (iii) a β1AR antagonist (bisoprolol). PBMCs isolated before and after exercise were stimulated with Adenovirus (AdV), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) peptide antigens and cultured for 8 days, after which VSTs were enumerated by IFNγ ELISPOT. Compared to resting conditions, exercise augmented the expansion of VSTs in the placebo and bisoprolol trials (38.2% and 57.9% increases), but not in the nadolol trial (3.3% decrease). We conclude that the augmenting effects of exercise on VST expansion are dependent on β2AR signaling, highlighting the β2AR as a potential target to increase the potency of T-cell therapeutics.

Acute exercise evokes an almost instantaneous lymphocytosis, which is followed by sustained lymphopenia within just 30–60 min of exercise cessation. The aim of this study was to characterize for the first time the immediate (order of minutes) post-exercise kinetics of lymphocyte egress, and to determine if lymphocyte egress is associated with heart rate recovery following exercise. 11 healthy subjects exercised for 30-min at 80 percent peak cycling power. Blood samples were collected from an intravenous catheter before exercise, during (+15 and + 30 min) exercise, and at exactly +1, +2, +3, +4, +5 and +10 min after exercise cessation. Complete blood counts and flow cytometry was used to enumerate total lymphocytes, CD3 + T-cells, CD4 + T-cells, CD8 + T-cells, NK-cells and gamma-delta T- cells in whole blood. Compared to the peak lymphocyte count during exercise, the lymphocyte count had fallen significantly (−14 percent) after just 2 min of exercise recovery. After 5 and 10 min of exercise recovery, the lymphocyte count was −23 percent and −28 percent of peak values, respectively. NK cells were fastest to egress peripheral blood, followed by CD8 + T-cells. Further, the egress of both NK-cells and CD8 + T-cells was strongly correlated with recovery heart rate upon exercise cessation. In conclusion, lymphocyte egress occurs within the first few minutes of exercise recovery and may be dependent on how quickly hemodynamic equilibrium is restored.

Studies aimed at determining the contribution of beta-adrenergic receptor signaling to stress-induced lymphocyte mobilization have failed to control for hemodynamic perturbations that accompany psychological stress, exercise, and/or epinephrine infusion. We aimed to determine the relative contribution of beta2-adrenergic receptor (B2-AR) signaling to the mobilization of various lymphocyte and monocyte subtypes with exercise while controlling for hemodynamic shear stress. Fourteen healthy subjects underwent 30 min of steady state cycling exercise under 3 different conditions separated by at least 7-days: placebo; beta1-preferential antagonist (10 mg bisprolol); and non-preferential beta1 and beta2- antagonist (80 mg nadolol). Drugs were administered 3 h prior to exercise in a randomized double-blind cross-over design. Blood samples were collected prior to drug administration, immediately before exercise, and immediately after exercise for immunophenotyping by flow cytometry. Compared to placebo, bisoprolol and nadolol reduced exercising heart rate and blood pressure to comparable levels, indicating that hemodynamic perturbations were similar between the two drug trials. Several lymphocyte and monocyte subpopulations (CD8 T-cells: CD28negCD27neg, CD45RAposCD62Lneg, KLRG1posCD57pos, KLRG1posCD57neg, CD45RAnegCD62Lneg, CD45RAnegCD62Lpos; NK Cells: NK cells (all), NKG2CposCD57neg, NKG2CnegCD57pos, NKG2CnegCD57neg; non-classical monocytes (CD14posCD16pos); and gamma delta T-cells) exhibited a B2-AR dependent response, as indicated by a blunted mobilization with nadolol compared to both bisoprolol and placebo. We conclude that 28–61 percent of the ‘exercise responsive’ lymphocytes and monocytes are dependent on B2-AR signaling for their mobilization into the peripheral blood compartment.

Natural Killer-cell cytotoxicity (NKCA) increases during recovery from exercise. The mechanism(s) underlying enhanced NKCA remain unknown. We therefore investigated the role of exercise-induced changes in cortisol and NK-cell subsets on NKCA. Methods Thirteen adults (7 women; 32 ± 7 years) cycled 30 min 15% above lactate threshold. NK-cells from pre-, post-, and 1 h post-exercise were incubated with U266 tumor-target cells in the presence of autologous serum. NKCA was assessed after 4 h in a flow cytometry based assay. To determine the effect of cortisol released during exercise, pre-exercise NK-cells and targets were incubated with pre-, post- and 1 h post-exercise serum. To determine the effect of shifts in NK-cell subsets, pre-, post-, and 1 h post-exercise NK-cells and targets were incubated with pre- exercise serum. Serum cortisol was assessed by ELISA. Results were analyzed using linear mixed models. Results The NKCA of pre-exercise NK-cells was enhanced in the presence of 1 h post-exercise serum (p Conclusions Serum obtained 1 h post-exercise enhanced resting NKCA and decreased the proportion of inhibitory NK-cells. This suggests that factors present in serum after exercise can alter effector cell function. Future work will analyze cytokines present in 1 h post-exercise serum.