Post-Graduate Program in Health Sciences, São Francisco University Medical School, Bragança Paulista, SP, Brazil.
Dig Dis Sci. 2011 Apr;56(4):1037-46. doi: 10.1007/s10620-010-1378-z. Epub 2010 Nov 2.
No studies have evaluated the effectiveness of 5-ASA against oxidative DNA damage in experimental models of diversion colitis.
To evaluate the effects of 5-ASA against oxidative DNA damage in an experimental model of diversion colitis.
Twenty-six Wistar rats were divided into two groups corresponding to sacrifice at 2 or 4 weeks after fecal diversion of the left colon by means of proximal colostomy and distal mucosa fistula. Each group was divided into two subgroups according to intervention in excluded colon performed with 0.9% saline solution or 5-ASA. Level of oxidative DNA damage was determined by comet assay in cells obtained from segments with and without fecal stream before and after H2O2 challenge. For statistical analysis, was used one-way analysis of variance (ANOVA), adopting a 5% significance level (P<0.05).
Levels of DNA damage were always higher in colon segments without fecal stream, regardless of the intervention solution employed. DNA damage in colon segments with and without fecal stream in animals irrigated with 5-ASA was lower when compared with those treated with saline solution, regardless of time of irrigation. These levels remained lower after intervention with 5-ASA, even after H2O2 challenge.
Enema with 5-ASA reduces oxidative DNA damage in epithelial cells of colon segments without fecal stream, even after H2O2 challenge, confirming the effects of 5-ASA against DNA damage by oxygen free radicals.
尚无研究评估 5-ASA 对分流性结肠炎实验模型中氧化 DNA 损伤的有效性。
评估 5-ASA 对分流性结肠炎实验模型中氧化 DNA 损伤的作用。
26 只 Wistar 大鼠被分为两组，每组分别在左结肠通过近端结肠造口和远端黏膜瘘进行粪便分流后 2 或 4 周进行处死。每组根据对排除的结肠进行的干预分为 2 个亚组，分别用 0.9%生理盐水或 5-ASA 进行干预。通过彗星试验在有和无粪便流的结肠段细胞中测定氧化 DNA 损伤水平，在 H2O2 刺激前后进行。采用单因素方差分析（ANOVA）进行统计分析，采用 5%的显著性水平（P<0.05）。
无论干预溶液如何，无粪便流的结肠段的 DNA 损伤水平始终更高。用 5-ASA 冲洗的动物的有和无粪便流的结肠段中的 DNA 损伤水平低于用生理盐水处理的动物，无论冲洗时间如何。即使在 H2O2 刺激后，用 5-ASA 进行干预后，这些水平仍保持较低。
灌肠用 5-ASA 可降低无粪便流的结肠段上皮细胞中的氧化 DNA 损伤，即使在 H2O2 刺激后也是如此，证实了 5-ASA 对氧自由基引起的 DNA 损伤的作用。
