大蒜对N-亚硝酰胺致突变作用的影响

MODULATION OF MUTAGENICITIES OF N-NITROSAMIDES BY GARLIC

大蒜摄入量与患胃癌的风险呈负相关,可能具有防胃癌作用。我们使用Ames试验探讨了大蒜对人胃癌可疑病因N-亚硝酰胺致突变性的影响。结果表明大蒜球茎匀浆在无毒性的剂量(5-15mg/皿)范围内有阻断100nmol/皿ENNG (N-ethyl-N′-nitro-N-nitrosoguanidine)、150nmol/皿的MNU(N-methyl-N-nitrosourea)和200μl/皿亚硝化鱼露直接致TA100回复突变作用,但在平板掺入试验中增强5nmol/皿MNNG(N-methyl-N′-nitro-N-nitrosoguanidine)致突变强度,在预培养试验中则抑制它的致突变作用。大蒜的有效成分大蒜素(0.1-0.3μmol/皿)能明显地阻断TA100的致突变性。以上结果证明大蒜及其有效成分有抗N-亚硝酰胺致突变的作用。文中对大蒜在特殊条件下促进MNNG致突变的机理进行了讨论。

It was reported that the intake amount of garlic was correlated woth the risk of gastric cancer ncgtivcly. The effect of garlic bulb homogenate (GBH) on rautagenicities of N-nitrosamidcs-the possible causes of gastric cancer was investigated with Ames tests. Results show that 5-15 mg/plate of GBH suppresses the rautagenicities of ENNG (l00nmol/plate), MUN (150 nmol/plate), and nitrosatcd fish sauce (containing 59.1 nmol/ml of total N-nitrosamidcs, 200/@@@ / plate) dose-dcpcndcntly. GBH, however, enhances the mutagcnicity of MNNG at doses of 5-10 mg/ plate in the plate incorporation test, but decreases its mutagcnictity in the preincubation test dose-dependently. Antimutagcnicity of diallyl trisulfidc is also observed in TAI00 treated with MNNG. These indicate that garlic and its active principle can prevent the mutagcnicities of N-nitrosamidcs. The mechanisms of modulation of mutagcnicity by garlic were discussed.