Immunopathology of exercise-induced bronchoconstriction in athletes--a new modified inflammatory hypothesis

The impact of tangeretin combined with whey protein on exercise-induced bronchoconstriction in professional athletes: a placebo-controlled trial

BACKGROUND

Exercise-induced bronchoconstriction (EIB) is highly prevalent in athletes. The objective of this study was to assess the therapeutic efficacy of daily tangeretin combined with whey protein supplementation over a period of 4 weeks in professional athletes with EIB.

METHODS

Using a placebo-controlled, double-blind, paired, randomized trial design, a cohort of 30 professional athletes with EIB, consisting of 14 females and 16 males, was divided into two groups: the tangeretin combined with whey protein intervention group (TIG), and the placebo control group (PCG). Both the TIG and PCG underwent exercise challenge tests (ECT) and VO2max tests before (ECT1, V1) and after (ECT2, V2) the intervention. Blood (eosinophils, neutrophils, and basophils) and serum (interleukin-5, IL-5; interleukin-8, IL-8; Clara cell secretory protein-16, CC16; immunoglobulin E, IgE) levels were measured early in the morning of ECT1 and ECT2, respectively. Lung function was assessed immediately before and post-ECT immediately.

RESULTS

Tangeretin combined with whey protein use for 4 weeks attenuated the decrease in forced expiratory volume in 1 s (FEV1) post trials (∆FEV1(ECT1-ECT2): mean (SD) TIG -7.51(6.9)% vs. PCG -2.33(11.49)%, p = 0.013). Tangeretin also substantially attenuated IL-5 concentration (∆IL-5(T1-T5): Tangeretin -19.4% vs Placebo + 8.37%, p = 0.022); IL-8 concentration (∆IL-8(T1-T5): Tangeretin -17.28% vs Placebo + 6.1%, p = 0.012); CC16 concentration (∆CC16(T1-T5): Tangeretin -11.77% vs Placebo + 24.19%); and IgE concentration in the serum (∆IgE(T1-T5): Tangeretin -24.1% vs Placebo -3.9%), and significantly decreased neutrophil count (∆N(T1-T5): Tangeretin -11.34% vs Placebo + 0.3%) and eosinophil count in blood (∆N(T1-T5): Tangeretin -38.5% vs Placebo + 4.35%). Compared with V1, VO2max (p = 0.042) and TLim (p = 0.05) of V2 were significantly increased in the TIG, and there was no significant change in the PCG. Meanwhile, six athletes in the TIG and 0 athletes in the PCG became EIB-negative at ECT2; the overall negative conversion rate of EIB was 40.00% in TCG. Additionally, the number of cough symptoms decreased from 9 to 3 and dyspnea from 4 to 2 in the TIG.

CONCLUSION

After high-intensity exercise, athletes with EIB achieved significant improvements in lung function and blood inflammatory factors by combining tangeretin and whey protein supplementation. EIB athletes also showed longer exercise endurance and VO2max at 4 weeks after TI. In addition, some patient symptoms disappeared after combination supplementation. The effect of this treatment on professional athletes with EIB was beneficial.

Mechanisms of exercise-induced bronchoconstriction in athletes: Current perspectives and future challenges

The evidence of exercise-induced bronchoconstriction (EIB) without asthma (EIBw_A ) occurring in athletes led to speculate about different endotypes inducing respiratory symptoms within athletes. Classical postulated mechanisms for bronchial obstruction in this population include the osmotic and the thermal hypotheses. More recently, the presence of epithelial injury and inflammation in the airways of athletes was demonstrated. In addition, neuronal activation has been suggested as a potential modulator of bronchoconstriction. Investigation of these emerging mechanisms is of major importance as EIB is a significant problem for both recreational and competitive athletes and is the most common chronic condition among Olympic athletes, with obvious implications for their competing performance, health and quality of life. Hereby, we summarize the latest achievements in this area and identify the current gaps of knowledge so that future research heads toward better defining the etiologic factors and mechanisms involved in development of EIB in elite athletes as well as essential aspects to ultimately propose preventive and therapeutic measures.

Influence of a montmorency cherry juice blend on indices of exercise-induced stress and upper respiratory tract symptoms following marathon running--a pilot investigation

Background

Prolonged exercise, such as marathon running, has been associated with an increase in respiratory mucosal inflammation. The aim of this pilot study was to examine the effects of Montmorency cherry juice on markers of stress, immunity and inflammation following a Marathon.

Methods

Twenty recreational Marathon runners consumed either cherry juice (CJ) or placebo (PL) before and after a Marathon race. Markers of mucosal immunity secretory immunoglobulin A (sIgA), immunoglobulin G (IgG), salivary cortisol, inflammation (CRP) and self-reported incidence and severity of upper respiratory tract symptoms (URTS) were measured before and following the race.

Results

All variables except secretory IgA and IgG concentrations in saliva showed a significant time effect (P <0.01). Serum CRP showed a significant interaction and treatment effect (P < 0.01). The CRP increase at 24 and 48 h post-Marathon was lower (P < 0.01) in the CJ group compared to PL group. Mucosal immunity and salivary cortisol showed no interaction effect or treatment effect. The incidence and severity of URTS was significantly greater than baseline at 24 h and 48 h following the race in the PL group and was also greater than the CJ group (P < 0.05). No URTS were reported in the CJ group whereas 50 % of runners in the PL group reported URTS at 24 h and 48 h post-Marathon.

Conclusions

This is the first study that provides encouraging evidence of the potential role of Montmorency cherries in reducing the development of URTS post-Marathon possibly caused by exercise-induced hyperventilation trauma, and/or other infectious and non-infectious factors.

Pediatric exercise-induced bronchoconstriction: contemporary developments in epidemiology, pathogenesis, presentation, diagnosis, and therapy

Exercise-induced bronchoconstriction is transient narrowing of the airways following strenuous exercise. It is the earliest sign of asthma and the last to resolve. EIB is found in 90 % of asthmatics and reflects underlying control of asthma. This review is focused on the contemporary developments in pediatric EIB: the epidemiology, pathogenesis, presentation, diagnosis and management. Proper diagnosis by objective pulmonary function and/or exercise challenge and therapy should allow the pediatric asthmatic to enjoy a healthy lifestyle including participation in the chosen sport.