Although regular bouts of moderate-intensity exercise provide several health benefits, acute high-intensity exercise can impair the immune system, particularly the mucosal immune system [1], and lead to oxidative stress [2]. Due to its content in polyphenols and other bioactive compounds, cocoa intake might help protecting against the oxidative damage and the impaired immune function [3]. Moreover, cocoa fibre, by influencing the intestinal immune system [4], could also play a protective role. The aim of this study was to establish the effect of cocoa and cocoa fibre on the oxidative status and the immunoglobulin (Ig) production of rats following an acute exercise bout on a treadmill. For this purpose, young female Wistar rats were fed either with a standard diet, a diet containing 5% cocoa fibre or a diet containing 10% cocoa for 4-weeks. At the end of the study, half of the rats remained sedentary and the second half performed an exhausting running test in a treadmill. The collection of peritoneal macrophages, blood, submaxillary salivary glands and intestinal samples was conducted 16 h later. The production of reactive oxygen species (ROS) by peritoneal macrophages and the concentration of serum and mucosal Ig was assessed. Acute exercise increased the ROS production while decreased the serum IgG concentration and the salivary gland IgM content. Cocoa fibre-enriched diet prevented both the higher production of ROS and the reduction in salivary IgM induced by exercise, although it decreased the IgA content in serum and salivary glands. The cocoa diet also altered the Ig profiles, evidencing higher impact in runner animals than in the sedentary ones. Overall, cocoa, by means of its fibre content, can partially prevent the alterations in ROS and Ig production induced by a single session of intensive running exercise.
References:
- Simpson, R.J.; Kunz, H.; Agha, N.; Graff, R. Exercise and the Regulation of Immune Functions. Mol. Cell. Regul. Adapt. to Exerc. 2015, 135, 355–380.
- Nunes-Silva, A.; Freitas-Lima, L.C. The association between physical exercise and reactive oxygen species (ROS) production. J Sport. Med Doping Stud 2015, 5, 152.
- Decroix, L.; Soares, D.D.; Meeusen, R.; Heyman, E.; Tonoli, C. Cocoa Flavanol Supplementation and Exercise: A Systematic Review. Sport. Med. 2018, 48, 867–892.
- Massot-Cladera, M.; Franch, À.; Pérez-Cano, F.J.; Castell, M. Cocoa and cocoa fibre differentially modulate IgA and IgM production at mucosal sites. Br. J. Nutr. 2016, 115, 1539–1546.
