Kaymak C, Kadioglu E, Ozcagli E, Osmanoglu G, Izdes S, Agalar C, Basar H, Sardas S
Faculty of Medicine, Department of Anesthesiology and Reanimation, Kirikkale University, Kirikkale, Turkey.
Hum Exp Toxicol. 2008 Jun;27(6):485-91. doi: 10.1177/0960327108088972.
Sepsis and septic shock remains as leading cause of death in adult intensive care units. It is widely accepted that gram-negative bacteria and their endotoxins cause sepsis and septic shock, predominantly. Enhanced generation of reactive oxygen species may be responsible for tissue injury in septic shock and endotoxemia. The aim of this study was to assess oxidative DNA damage and the total antioxidant status (TAS) in peripheral lymphocytes of rats during different intraperitoneal gram-negative sepsis stages. Adult male Sprague-Dawley rats were divided randomly into four groups. Control group was intraperitoneally inoculated with 2 mL of pyrogene-free saline (Group I, n = 6), and the other rats received an intraperitoneal inoculum with 2 mL of saline containing 2 x 10(8) CFU of Escherichia coli. The animals were killed at time zero (Group I, n = 6), at 6th (Group II, n = 7), 12th (Group III, n = 7), and 24th (Group IV, n = 7) hour after the E. coli inoculation. Oxidative DNA damage in peripheral lymphocytes of rats was evaluated by modified comet assay (single-cell gel electrophoresis). Formamidopyrimidine DNA glycosylase (Fpg) and Endonuclease III (Endo III) were used to detect oxidized purines and pyrimidines, respectively. Total antioxidant quantification was carried out using ABTS+ (2,2'-Azino-di-[3 ethylbenzthiazoline sulphonate]) radical formation kinetics (Randox kit) in serum samples. Significant elevations of basal levels of strand breaks (SB) in Group IV were observed as compared with Group I, II, and III. There was a significant increase in Fpg sites in Group III as compared with Group I and II. However, there was no significant difference in terms of Endo III sites in any of the groups. Although the TAS was decreased with the stages of sepsis, this moderate decrease was significant in only Group IV as compared with Group I. There was no statistically significant correlation between DNA damage and TAS for any of the groups.
脓毒症和脓毒性休克仍然是成人重症监护病房的主要死亡原因。革兰氏阴性菌及其内毒素主要导致脓毒症和脓毒性休克，这一点已被广泛接受。活性氧的生成增加可能是脓毒性休克和内毒素血症中组织损伤的原因。本研究的目的是评估大鼠在不同腹腔内革兰氏阴性菌脓毒症阶段外周淋巴细胞中的氧化性DNA损伤和总抗氧化状态（TAS）。成年雄性Sprague-Dawley大鼠被随机分为四组。对照组腹腔注射2 mL无热原生理盐水（第一组，n = 6），其他大鼠腹腔接种2 mL含2×10⁸CFU大肠杆菌的生理盐水。在接种大肠杆菌后的第0小时（第一组，n = 6）、第6小时（第二组，n = 7）、第12小时（第三组，n = 7）和第24小时（第四组，n = 7）处死动物。通过改良彗星试验（单细胞凝胶电泳）评估大鼠外周淋巴细胞中的氧化性DNA损伤。分别使用甲酰胺嘧啶DNA糖基化酶（Fpg）和核酸内切酶III（Endo III）检测氧化的嘌呤和嘧啶。使用ABTS⁺（2,2'-联氮-二-[3-乙基苯并噻唑啉-6-磺酸]）自由基形成动力学（兰多克斯试剂盒）对血清样本进行总抗氧化剂定量。与第一组、第二组和第三组相比，第四组中链断裂（SB）的基础水平显著升高。与第一组和第二组相比，第三组中Fpg位点显著增加。然而，各组之间在Endo III位点方面没有显著差异。尽管TAS随着脓毒症阶段而降低，但与第一组相比，这种适度降低仅在第四组中具有显著性。任何一组的DNA损伤与TAS之间均无统计学显著相关性。
