ORIGINAL ARTICLES   

The Journal of Sports Medicine and Physical Fitness 1998 June;38(2):111-5

Copyright © 1998 EDIZIONI MINERVA MEDICA

lingua: Inglese

Effects of intensive endurance exercise on DNA damage in leucocytes

Niess A. M., Baumann M., Roecker K., Horstmann T., Mayer F., Dickhuth H. H.

Medical Clinic and Polyclinic, Division of Sport Medicine, University of Tübingen, Germany

Objec­tive. It has ­been ­shown ­that high­ly inten­sive anaer­o­bic exer­cise induc­es DNA dam­age in leu­coc­y­tes (LEU). The ­present ­study was ­designed to inves­ti­gate wheth­er inten­sive endu­rance exer­cise is ­capable of induc­ing com­par­able ­effects.
Experi­men­tal ­design. A pros­pec­tive ­study.
Par­tic­i­pants. ­Twelve men (­aged 27.3±4.1 ­years) who under­took a reg­u­lar train­ing of dif­fer­ent ­extent (run­ning vol­ume 45±25 km· ­week-1) vol­un­teered in the ­study.
Inter­ven­tions. The sub­jects com­pet­ed in a ­half mar­a­thon (HM) of 21.1 km, 93.0±10.4 min.
Meas­ure­ments. ­Blood was tak­en at ­rest, 1 and 24 hrs ­after HM for deter­mi­na­tion of crea­tine ­kinase, neu­troph­il (PMN), lym­pho­cyte and mono­cyte ­counts. DNA dam­age in LEU at ­rest and 24 hrs ­after HM was quan­ti­fied ­using the sin­gle ­cell gel-elec­tro­pho­re­sis (SCG) ­assay.
­Results. PMN ­increased ­from 2.81±0.69 to 13.13±2.91 1 hrs ­after HM (p<0.01) and ­returned to 3.26±0.47 109 ­cells·l-1 by 24 hr recov­ery. DNA migra­tion (­image ­length, IL) reflect­ing the ­extent of DNA dam­age was ele­vat­ed sig­nif­i­cant­ly in 10 of 12 sub­jects one day ­after HM. IL ­rose ­from 32.7±2.2 to 40.7±3.9 µm (p<0.01). Cor­re­la­tion anal­y­sis ­revealed a rela­tion­ship ­between DNA migra­tion 24 hrs ­after HM and PMN ­count 1 hr ­post-exer­cise (r=0.67, p<0.05).
Con­clu­sions. The ­results con­firm the hypoth­e­sis ­that DNA dam­age in LEU ­occurs ­after inten­sive endu­rance exer­cise. We sup­pose our obser­va­tion of exer­cise-­induced DNA dam­age in LEU is affect­ed by reac­tive oxy­gen spe­cies ­which are ­released ­from PMN. It is ­quite ­unclear wheth­er DNA dam­age in LEU is cau­sal ­involved in exer­cise-­induced mod­ifi­ca­tions of the ­immune ­system.