丙烯酰胺对黑腹果蝇寿命及SOD和MDA的影响

Effects of acrylamide on life-span,superoxide dismutase activity and maleic dialdehyde content of drosophila melanogaster

目的研究丙烯酰胺(acrylamide)对黑腹果蝇寿命及抗氧化系统的影响。方法经口喂饲果蝇不同浓度丙烯酰胺,通过急性毒性试验测定丙烯酰胺半数致死浓度(median lethal dose,LC50),采用生存实验记录果蝇寿命,测定丙烯酰胺不同染毒浓度和时间果蝇体内超氧化物歧化酶(superoxide dismutase,SOD)活性及丙二醛(maleic di-aldehyde,MDA)含量。结果急性毒性试验中,在95%置信度下丙烯酰胺溶液对雌性果蝇的LC50为201.00±24.68 mg/L,对雄性的LC50为20.00±1.21 mg/L。生存试验中染毒后各剂量组雌雄果蝇半数死亡时间、平均寿命及平均最高寿命与对照组相比均缩短(P<0.05或P<0.01),呈现明显的剂量-反应关系。不同浓度染毒组雌雄果蝇在不同染毒时间与对照组相比,SOD活性显著降低(P<0.05),MDA含量显著升高(P<0.05),存在剂量-反应关系。结论丙烯酰胺可促进果蝇体内脂质过氧化反应、破坏果蝇体内抗氧化系统的平衡,可能是果蝇寿命缩短的原因之一。

Objective To study the effects of acrylamide on lifespan and antioxidation system of drosophila melanogaster. Methods Acrylamide of different concentrations were administrated orally to different groups of drosophila melanogaster. Median lethal dose （LC50） was estimated by acute toxicity test; lifespan was tested by drosophila survival experiment; superoxide dismutase （SOD） and maleic diadehyde （MDA） were evaluated at different periods. Results The calculation of median lethal concentration that the soltion of acrylamide has an effect on the female drosophila is 201.00 ± 24.68 mg/L , and the male drosophila is 20.00 ± 1.21 mg/L in 95 % confidence level. There was a dose-response relationship between concentration of acrylamide and mortality rate of drosophila in acute toxicity test. Median lethal time, mean lifespan and mean maximum lifespan of drosophila fed with different concentration of acrylamide were lower thanl groups dominantly （P〈 0.05 or P〈 0.01 ） in survival experiment, and a dose-response relationship has been shown. The SOD activity decreased and MDA concentration increased significantly （P〈 0.05） with prolonged exposure and increased concentration of acrylamide,that was fitted with a time-dose-response relationship. Conclusion A certain amount of acrylamide could promote the process of lipid peroxidation and disturb the balance of antioxidation system of drosophila melanogaster. It should be one of the reasons of its shortened lifetime.