In our previous studies, we reported increased neutrophil (PMN) differential counts in induced sputum ofmarathon (M) runners (Bonsignore et al, 2001). Conversely, increased bronchial epithelial cell (BEC) differentialcounts were found in half-marathon (HM) runners (Chimenti et al, 2010). To better understand the differencespreviously found between M and HM runners, we studied 11 non-asthmatic amateur athletes (HM n=6, M n=5,age: 44.5±6.7 yrs, race time: HM 101±18 min, M 218±35 min) participating to the 2012 Palermo Marathon. Wecollected induced sputum samples 4 to 5 days before the race (PRE), 2 hours after the race (RACE), and thefollowing morning (POST). Induced sputum was processed according to the plug technique. In both HM and M runners, PMN differential counts increased from PRE to RACE and remained elevated in POST,whereas BEC differential counts increased from PRE to RACE, but returned to baseline at POST. These preliminaryresults indicate that BEC damage, possibly induced by hyperosmolar exposure during exercise hyperpnea, occursfor the entire duration of endurance exercise but is transient. Conversely, PMNs were recruited in the airways for alonger time, possibly secondary to chemiotactic stimuli released by BEC during exercise. Lack of differencesbetween HM and M runners suggests that duration of the endurance race does not affect the airway cell responseto exercise.
|Stato di pubblicazione||Published - 2013|