Fototerapia causa danos ao DNA de leucócitos mononucleares periféricos em recém-nascidos a termo

Abstract

Objective: Our aim was to determine whether endogenous mononuclear leukocyte DNA strand is a target of phototherapy. Methods:The study included 65 term infants aged between 3-10 days that had been exposed to intensive (n = 23) or conventional (n = 23) phototherapy for at least 48 hours due to neonatal jaundice, and a control group (n = 19). DNA damage was assayed by single-cell alkaline gel electrophoresis (comet assay). Plasma total antioxidant capacity and total oxidant status levels were also measured, and correlation between DNA damage and oxidative stress was investigated.Results: Mean values of DNA damage scores in both the intensive and conventional phototherapy groups were significantly higher than those in the control group (p < 0.001). Mean values and standard deviation were 32 (9), 28 (9), 21 (7) arbitrary unit, respectively. Total oxidant status levels in both the intensive and conventional phototherapy groups were significantly higher than those in the control group (p = 0.005). Mean (standard deviation) values were 18.1 (4.2), 16.9 (4.4), 13.5 (4.2) µmol H 2 O 2 equivalent/L, respectively. Similarly, oxidative stress index levels in both the intensive and conventional phototherapy groups were significantly higher than those in the control group (p = 0.041).Plasma total antioxidant capacity and total bilirubin levels did not differ between the groups (p > 0.05). There were no significant correlations between DNA damage scores and bilirubin, total oxidant status and oxidative stress levels in either phototherapy group (p > 0.05). Conclusions:Both conventional phototherapy and intensive phototherapy cause endogenous mononuclear leukocyte DNA damage in jaundiced term infants.J Pediatr (Rio J). 2008;84(2):141-146: DNA damage, comet assay, hyperbilirubinemia, oxidative stress, phototherapy.

An Increased Genotoxic Risk in Lymphocytes from Phototherapy-Treated Hyperbilirubinemic Neonates

“…However, we attempted to morphologically evaluate apoptosis using the neutral comet assay. In addition, most studies investigated the effects of jaundice and/or phototherapy on DNA damage in neonates using the alkaline comet assay[3,5,6,11], which allows the detection of both single and DSBs[37]. In contrast, the present study used the neutral comet assay that has the ability to detect only DSBs, which are more important than single strand breaks to induce chromosomal aberrations[38] and apoptotic responses at the cellular level[21].…”

MCF-7 ve PC-3 Hücre Hatlarında, Hücre Canlılığı ve DNA Hasarı Üzerine TRPV4 Antagonisti RN 1734'ün Etkileri

“…Her lamdan rastgele en az 25 hücre sayıldı ve her görüntü kuyruklu yıldız kuyruğundaki floresan yoğunluğuna göre sınıflandırıldı. Skorlamada 0, 1, 2, 3 veya 4 (Skor 0: hasar görmemiş, Skor 4: maksimum hasar görmüş) değerleri kullanıldı [20,21]. [22].…”