2种有机污染物对鲈鱼生化标志物系统的影响及作用评价

Effects of Two Organic Pollutants on Biomarker System of Fish Lateolabrax japonicus and the Pollution Assessment

实验生态条件下筛选了鲈鱼的一组生化标志物组成生化标志物系统,研究其对不同有机污染胁迫的响应差异.将鲈鱼分别暴露于2种有机污染物:0.1 mg/L、1 mg/L的十二烷基苯磺酸钠(SDBS)和2μg/L、20μg/L的苯并[a]芘(B[a]P),研究长时间(18 d)、亚致死污染胁迫下鲈鱼生化标志物系统各组分:肝脏组织抗氧化酶中的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(Gpx)、谷胱甘肽(GSH)、谷胱甘肽硫转酶(GST)以及诱导型一氧化氮合酶(iNOS)和脑组织中乙酰胆碱脂酶(AChE)活性的变化,同期检测了热激蛋白70(Hsp70)表达的变化,并对所得到的结果进行了主成分分析(PCA).结果表明,①与未受胁迫的对照组相比,B[a]P胁迫能够显著诱导鲈鱼体内的SOD、GST、Gpx活性以及GSH含量的变化(p<0.05),但对其它几种酶的活性影响并不明显;SDBS胁迫对CAT、Gpx、iNOS和AChE活性的诱导作用明显,但对SOD、GST和GSH的影响较小.Gpx是对2种污染物胁迫响应最灵敏的一种生化标志物.②同时测定了不同胁迫条件下鲈鱼血细胞Hsp70表达的影响,结果发现其在SDBS胁迫组中的表达始终高于对照组,而B[a]P在胁迫前期能诱导Hsp70表达升高,以后逐渐下降至对照水平.③鲈鱼的生化标志物系统的不同组分对不同种类的污染胁迫响应有明显差异,对结果进行主成分分析(PCA)后发现,基于PCA和生化标志物系统的研究方法能有效区分不同污染因子的作用,可能在海洋环境污染的早期、预警性评价中具有良好的应用前景.

Responses of a select suite of protective enzymes in Lateolabrax japonicus including superoxide dismutase （SOD）, catalase （ CAT）, glutathione peroxidase （ Gpx）, reduced glutathione （GSH） glutathione S-transferase （ GST）, nitric oxide synthase （iNOS） in liver tissue and brain acetylcholinesterase （ACHE）, which could work as sensitively biochemical biomarkers were analyzed when exposed to different concentrations of sodium dodecylbenzene sulfonate （SDBS） and benzo[ a ] pyrene （ B [ a ] P） under controlled laboratory conditions. Results showed that：① The biochemical biomarkers included in this investigation,different responses occurred in the enzymatic activities when exposed to different pollutants： the activities of SOD, GST, Gpx and GSH content were significantly induced by B[ a ] P （p 〈 0. 05 ） while others present little different as compared to the control. Differently, SDBS exposure greatly affected the activities of CAT, Gpx,iNOS and AChE while showed little effect on the other evaluated biomarkers. Gpx was the most sensitive biomarker that sensitively indicated the organic pollution stress. ② The simultaneous assay on heat shock protein 70 （Hsp70） expression was conducted by flow cytometry （FCM） and result presented that Hsp 70 expression could be effectively induced by SDBS as compared to the control throughout the experiment; however, B [ a]P obviously induced Hsp70 during the first 12 d and then decreased to the level of the control. ③ The evaluated method of biomarker system combined with principal component analysis （PCA） could effectively distinguish different pollutants under controlled laboratory conditions and might be a promising and warning method for the early assessment of environmental change exposed to different organic pollutions.