The assessment of DNA damage and repair following exposure to sevoflurane in vivo

Abstract

Cilj istraživanja bio je istražiti povezanost oštećenja i popravka DNA u leukocitima periferne krvi, stanicama jetre, bubrega i mozga Swiss albino miševa uzrokovanog uzastopnim izlaganjem sevofluranu. Miševi su bili izlagani sevofluranu u dozi od 2.4 vol% po dva sata dnevno, 3 dana uzastopce. Za procjenu genetičkog oštećenja spomenutih stanica upotrijebljeni su komet test i mikronukleus test. Za provođenje komet testa miševi su podijeljeni u 5 pokusnih skupina (kontrolna skupina, skupina miševa žrtvovanih treći dan pokusa neposredno nakon izlaganja sevofluranu, 2 sata, 6 sati i 24 sata nakon izlaganja sevofluranu). Rezultati su pokazali statistički značajno povećanje srednje vrijednosti TL, TM i TI u svim pregledanim organima u usporedbi sa kontrolom. Veličina oštećenja DNA u točno određenom vremenu nakon uzastopnog izlaganja sevofluranu, bila je drugačija za svaki pregledani organ. Najveće oštećenje DNA uočeno je odmah nakon izlaganja sevofluranu, posebno u leukocitima periferne krvi. Inducirano oštećenje se dogodilo šest sati kasnije u organima nego u stanicama krvi, što je bilo za očekivati zbog toksikokinetike lijekova, jer se sevofluran prvo apsorbira u krvi. Niti jedno od proučavanih tkiva nije pokazivalo znakove popravka sve dok nisu prošla 24 sata od izlaganja sevofluranu. Za detektiranje nepopravljenih oštećenih dijelova genoma in vivo upotrijebljen je mikronukleus test. Broj mikronukleusa u retikulocitima statistički se značajno povećao u svim proučavanim vremenskim razmacima nakon tretmana u odnosu na kontrolnu skupinu.Aim of the study was to investigate the relationship between DNA damage and repair of peripheral blood leucocytes (PBL), liver, kidney and brain cells of Swiss albino mice induced by repeated exposure to sevoflurane. Mice were exposed to sevoflurane in a dose of 2.4vol% for two hours daily, for three consecutive days. Genetic damage of mentioned cells was investigated using comet assay and micronucleus test. To perform comet assay, mice were divided into 5 experimental groups (control group, groups of exposed mice sacrificed third day of experiment immediately after exposure ot sevoflurane, two hours, six hours and twenty-four hours later). The results showed statistically significant increase in mean TL, TM and TI values in all examined organs vs. the control group. The DNA damage at a specific time after the repeated exposure to sevoflurane was different for each examined organ. Significant DNA damage immediately post exposure to sevoflurane was observed in PBL. The induced damage in organs occured 6 hours later than in PBL what was expected according to toxicokinetic of drugs, where blood is the first compartment to absorb the sevoflurane. However none of the assayed tissues revealed signs of repair until 24th hour after the exposure. To distinguish unrepaired genome damage in vivo micronucleus test was applied. Number of micronuclei in reticulocytes showed statistically significant increase compared with control group at all observed times after the treatment