精氨酸和谷氨酰胺对胃黏膜癌前病变影响的实验研究

目的:研究精氨酸(Arg)和谷氨酰胺(Gln)对大鼠胃黏膜细胞癌前病变的影响。方法:100只大鼠随机分为对照组、正常组、实验A组、实验B组和实验C组,每组20只。三个实验组和对照组大鼠喂饲N-甲基-N-硝基-亚硝基胍(MNNG),诱导胃黏膜异型增生,建立胃黏膜癌前病变模型。造模成功后,对照组和正常组喂饲能全素,实验A组喂饲能全素添加Arg+Gln组、实验B组喂饲能全素添加Arg、实验C组喂饲能全素添加Gln,实验共8周。观察大鼠的免疫功能、癌基因bcl-2、c-myc的表达和胃黏膜形态学变化。结果:与对照组比,实验A组、B组和C组白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平均下降;CD4+水平和CD4+/CD8+比值均升高;IgA、IgM水平升高,癌基因bcl-2、c-myc表达明显减少,肠上皮化生、异型增生发生率明显下降。实验A组的癌基因bcl-2、c-myc表达、肠上皮化生和异型增生发生率明显低于实验B组和实验C组。与正常组比,对照组IL-6、TNF-α水平显著升高,IgA、IgG、IgM、CD4+水平和CD4+/CD8+比值显著下降,癌基因bcl-2、c-myc表达显著增加,肠上皮化生、异型增生发生率显著升高。结论:Arg和Gln能改善大鼠的免疫功能,通过抑制原癌基因bcl-2、c-myc的表达,减少胃黏膜肠上皮化生和异型增生,阻止胃黏膜癌前病变。

Effects of glutamine and arginine on the gastric precancerous lesions in rats

Objective: To investigate the effect of glutamine and arginine on gastric precancerous in Sprague-Dawley rats.Methods: One-hundred rats were randomly divided into test A group(n=20),test B group(n=20),test C group(n=20),control group(n=20),normal group(n=20).N-methyl-N-nitro-N-nitrosoguanidine(MNNG,100μg/mL) was used feeding rats to make animal model of gastric precancerous lesions.All rats were fed with Nutrison as base enteral nutrition.The rats in testA,testB and testC groups were added with glutamine+arginine,arginine and glutamine in Nutrison,respectively.After 8 weeks,all rats were killed.Immune function were measured.Expression of oncogenes were also determined.Histopathological changes of gastric mucosa were observed.Results: The levels of T-lymphocyte subsets CD4,the ratio of CD4/CD8,immunoglobulin A(IgA)and immunoglobulin M(IgM) were higher,but the levels of tumor necrosis factor(TNF-α) and interleukin-6(IL-6) were lower in test A,test B,test C groups than those in the control group.Compared with the control group,the expression of bcl-2,c-myc and the incidence of mild to severe metaplasia,dysplasia were significantly lower in test A,test B,test C groups.The expression of bcl-2,c-myc and the incidence of mild to severe metaplasia,dysplasia were lower in test A than those in test B,test C groups.There were not statistic difference among test B,test C groups.Compared with normal group,the levels of IgA,IgM,IgG,CD4 and the ratio of CD4/CD8 were lower,the levels of TNF-α,IL-6 and CD8 were significantly highter in control groups.The expression of bcl-2,c-myc and the incidence of mild to severe metaplasia,dysplasia were significantly higher in control group than those in normal group.Conclusion: Glutamine and arginine can regulate immune function and cell proliferation and effectively intervene in the development of gastric precancerous lesions in rats.