茶多酚对苯并a芘致青鳉鱼后代发育畸形的拮抗作用

摘要

The effects of green tea polyphenols on the malformations of the fertilized eggs of Japanese medaka (Oryzias latipes) induced by benz[a]pyrene was investigated by using the biological model of spawning Japanese medaka (Oryzias latipes) with the method of intraperitoneal injection, and the real-time PCR was used to detection the mRNA expression of CYP enzymes (CYP1A1, CYPlB, CYP2A, CYP2C, CYP2D, CYP3A) and the GST gene (mGST, GST-a) in the liver medaka. The results showed that the malformation rate of the fertilized eggs of Japanese medaka in the treatment of injection of benzo[a]pyrene which was significantly higher than the DMSO control. The malformation rate in the treatments of tea polyphenols was decreased, the treatments except the lowest dose of tea polyphenols (20 μg/g BaP +2 μg/g TP) were significantly different compared to the BaP treatment. Real-time quantitative PCR results showed that the benzo[a]pyrene model group slightly induces the CYP1A1, CYP1BCYP2A,CYP2C, CYP2D mRNA expression and significantly inhibits the mGST and GST-α mRNA expression of the female medaka, while tea polyphenols can significantly inhibit the expression CYP1A1 mRNA gene and glutathione-S transferase (GST) gene mGST and GST-α. The antagonistic mechanism of green tea polyphenols on the malformation of the fertilized eggs of Japanese medaka induced by benzo[a]pyrene might be correlated with the inhibition of CYP1A1 mRNA gene expression and the acceleration of the excretion of metabolic product of benzopyrene.%为了研究茶多酚对苯并[a]芘致日本青鳉鱼后代畸形的拮抗及其可能机理,本研究采用正在产卵的青鳉鱼为模式生物,采用腹腔注射法研究了茶多酚对苯并[a]芘致其后代发育畸形的影响,并用逆转录-实时荧光定量PCR法检测肝脏组织内的CYP酶(CYP1A1、CYP1B、CYP2A、CYP2C、CYP2D、CYP3A)和GST基因(mGST、GST-a)的mRNA表达情况.结果表明,单独注射苯并[a]芘组日本青鳉鱼后代畸形率达到15.13%,显著高于对照;茶多酚拮抗组后代畸形率有所下降,除茶多酚最低剂量组(20 μg/g BaP+2μg/g TP)外,其他组与BaP组间均存在显著差异.实时荧光定量PCR结果表明,苯并芘试验组对CYP1A1、CYP1B、CYP2A、CYP2C、CYP2D有轻微诱导,并显著抑制雌鱼mGST和GST-a的表达,同时茶多酚可明显抑制CYP1A1基因和谷胱甘肽-S转移酶基因mGST和GST-a的表达.表明茶多酚的抗畸变机理可能与抑制CYP1A1基因表达以及加速苯并芘代谢有关.