Comparative analysis of peripheral and cellular inflammatory responses in young and master athletes Differential Inflammatory Responses to Acute Exercise and Ex Vivo Immune Challenge in Young and Master Athletes

Luciele Guerra Minuzzi^1*Alexandre Abilio De Souza Teixeira²Caique Figueiredo¹Gilson Dorneles³Anna Cláudia Castelo Branco⁴Bruna Spolador De Alencar Silva¹Pedro L. Valenzuela^5,6Alessandra Peres³Alejandro Lucia⁷Maria Notomi Sato⁸José Cesar Rosa Neto²Karsten Krüger⁹Fabio Lira^1*

• ¹Exercise and Immunometabolism Research Group, Postgraduation Program in Movement Sciences, Department of Physical Education, Sao Paulo State University (UNESP), Presidente Prudente, São Paulo, Brazil
• ²Immunometabolism Research Group, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
• ³Laboratory of Cellular and Molecular Immunology, Federal University of Health Sciences of Porto Alegre (UFCSPA), Porto Alegre, Brazil
• ⁴Department of Dermatology, Faculty of Medicine, University of São Paulo, São Paulo, São Paulo, Brazil
• ⁵Department of Systems Biology, Faculty of Medicine and Health Sciences, University of Alcalá, Alcalá de Henares, Madrid, Spain
• ⁶Physical Activity and Health Research Group (PaHerg), Research Institute of Hospital 12 de Octubre (imas12), Madrid, Spain
• ⁷Department of Sports Sciences, Faculty of Medicine, Health and Sports, Universidad Europea de Madrid, Madrid, Spain
• ⁸Laboratory of Medical Investigation-56, Department of Dermatology, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
• ⁹Department of Exercise Physiology and Sports Therapy, Institute of Sport Science, Justus-Liebig-University Giessen, Giessen, Germany

Background: Lifelong exercise is associated with beneficial immune adaptations, but the extent to which these adaptations manifest during an acute inflammatory challenge remains unclear.Therefore, we aimed to compare the inflammatory responses to ex vivo whole blood and peripheral blood mononuclear cells [PBMCs] cultures from young and master athletes, before and after a single bout of moderate-intensity exercise.Methods: Young (n=7; 22 ± 4 years) and master (n=12; 52 ± 9 years) female and male athletes with similar performance levels performed a 30-minute bout of moderate-intensity exercise.Blood samples were collected before and post-exercise to assess cytokine production in whole blood and PBMCs after stimulation with lipopolysaccharide [LPS] and a cocktail with phorbol 12-myristate 13-acetate [PMA] plus ionomycin.In whole blood, LPS induced higher interleukin [IL]-6 release in both groups, with a greater increase in young athletes at post-exercise (p=0.014). Tumor necrosis factor [TNF]-α levels increased only in young athletes (p<0.0001). In PBMCs, master athletes showed lower LPS-induced TNF-α release, increasing only post-exercise (p<0.034), whereas young athletes responded at both baseline (p<0.001) and post-exercise (p=0.003). Under PMA/ionomycin stimulation, TNF-α (p<0.0001) and interferon (IFN)-γ (p=0.007) release increased only in young athletes, while IL-6 production decreased in young athletes at baseline (p=0.002) and post-exercise (p=0.003).Young athletes exhibit a stronger cytokine response to ex vivo inflammatory stimuli, while master athletes demonstrate a more controlled and regulated inflammatory profile.