甘草酸对H_2O_2诱导小肠上皮细胞DNA损伤的保护作用  

Effect of Glycyrrhizic Acid on Protecting Instestinal Epithelial Cells from H_2O_2-induced DNA Damage

作　　者：张娴 黄羽 曾星 

机构地区：[1]广州中医药大学第二附属医院,广州510006

出　　处：《中药新药与临床药理》2012年第3期239-242,共4页Traditional Chinese Drug Research and Clinical Pharmacology

基　　金：国家自然科学基金项目(81001563)

摘　　要：目的初步研究甘草酸(Glycyrrhizic acid,GA)对氧化损伤小肠上皮细胞IEC-6的保护作用及可能机制。方法实验设空白对照组,H2O2模型组,GA低、中、高剂量组(50,100,200μg/mL)。GA各组加入相应浓度的药物作用48 h后,与模型组一起加入200μmol/L的H2O2作用2 h,空白对照组正常培养。用单细胞凝胶电泳检测DNA损伤,RT-PCR检测p53,Gadd45α mRNA表达,Western blot检测p53,Gadd45α蛋白表达。结果与空白对照组比较,模型组DNA损伤严重,Gadd45α mRNA和蛋白表达增高;与H2O2模型组比较,GA各组DNA损伤明显减轻,GA100μg/mL和200μg/mL组p53 mRNA及其蛋白表达明显升高,同时Gadd45α mRNA及其蛋白表达明显升高。结论 GA在100～200μg/mL可以保护H2O2诱导的小肠上皮细胞DNA损伤,其机制可能与p53和Gaad45α的表达增高相关。Objective To observe the protective effect of glycyrrhizic acid（GA） on DNA damage of intestinal epithe- lial cells （IEC-6） induced by H2O2, and to investigate the potential mechanism. Methods Five groups including blank control, H2O2 model, GA50 μg/mL, GA100μg/mL, GA200 μg/mL groups were set up in this study. Cells were cultured with blank control medium or GA of the fixed dosages for 48h, and then were stimulated with 200 μmol/L H2O2 for 2 h. DNA damage was analyzed by single cell gel electrophoresis assay. P53, Gadd45a mRNA was evaluated by RT-PCR. Expression of p53 and Gadd45α protein was detected by western blot. Results Compared with the blank control group, DNA of IEC-6 in the the H2O2 model group was severely damage, and Gaad45α mRNA and protein expression was increased. After treatment with GA of 100μg/mL or 200μg/mL for 48 h, DNA damage re- duced significantly, expression of p53 mRNA and protein both increased. Meanwhile, Gadd45α mRNA and protein expression was also increased. Conclusion The above results indicated GA of 100-200 μg/mL protects IEC-6 from DNA damage induced by H2O2, which mechanism is probably related with the increase of p53 and Gadd45α expres-sion.

关 键 词：甘草酸 DNA损伤 小肠上皮细胞 p53 Gaad45α 

分 类 号：R285.5[医药卫生—中药学]