胭脂红对黑腹果蝇寿命及SOD和MDA的影响

目的研究人工合成偶氮类色素胭脂红对黑腹果蝇的寿命及抗氧化系统的影响。方法经口喂饲果蝇不同浓度胭脂红,通过急性毒性试验测定胭脂红半数致死浓度(median lethal dose,LC50),采用生存试验检测果蝇寿命,测定不同时间果蝇体内总超氧化物歧化酶(superoxide dismutase,SOD)活性及丙二醛(maleic dialdehyde,MDA)含量。结果急性毒性试验中,胭脂红浓度与雌雄果蝇的死亡率呈剂量-反应关系。生存试验中各浓度组雌雄果蝇的半数死亡时间、平均寿命及平均最高寿命均较对照组缩短(P<0.05或P<0.01),且存在剂量-反应关系。随着胭脂红染毒时间的延长和染毒浓度的增加,雌雄果蝇体内SOD活力明显下降、MDA含量明显升高(P<0.05),呈剂量-反应关系。胭脂红对果蝇的毒性作用存在性别差异。结论胭脂红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。

Effects of ponceau 4R on life-span, superoxide dismutase activity and maleic dialdehyde content of Drosophila melanogaster

Objective To study the effects of ponceau 4R,an artificial synthetic Azo pigments,on lifespan and antioxidation system of Drosophila melanogaster.Methods Ponceau 4R was administrated orally to different groups of Drosophila melanogaster.Median lethal dose(LC(50)) 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 There was a dose-response relationship between concentration of ponceau 4R 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 ponceau 4R were lower than those in control groups dominantly(P<0.05 or P<0.01) in survival experiment,and a dose-response relationship was shown. The SOD activity decreased and MDA concentration increased significantly(P<0.05) with prolonged exposure and increased concentration of ponceau 4R,that was fitted with a time-dose-response relationship.Sex difference was observed during these experiments.Conclusion A certain amount of ponceau 4R can promote the process of lipid peroxidation and disturb the balance of antioxidation system of Drosophila melanogaster.This might be one of the reasons of shortening of its lifetime.