Vlahović Milena, Ilijin Larisa, Lazarević Jelica, Mrdaković Marija, Gavrilović Anja, Matić Dragana, Mataruga Vesna Perić
University of Belgrade, Institute for Biological Research "Siniša Stanković", Department of Insect Physiology and Biochemistry, Despot Stefan Blvd. 142, 11060 Belgrade, Serbia.
University of Belgrade, Institute for Biological Research "Siniša Stanković", Department of Insect Physiology and Biochemistry, Despot Stefan Blvd. 142, 11060 Belgrade, Serbia.
Comp Biochem Physiol C Toxicol Pharmacol. 2014 Mar;160:9-14. doi: 10.1016/j.cbpc.2013.11.002. Epub 2013 Nov 11.
Cadmium uptake takes place mainly through food. Lymantria dispar larvae were exposed to dietary cadmium in concentrations of 10 and 30μg Cd/g dry food (NOEC, no-observed-effect and LOEC, lowest-observed-effect concentration, respectively) for acute and chronic treatment and recovery. We established that metal contamination decreased mass only during the chronic treatment at 30μg Cd/dry food with no recovery on removal of cadmium for 3days. Significant reduction of protease activity was detected at LOEC after the acute and chronic treatments. Protease showed enhanced plasticity with regard to the fitness trait (mass) during environmental stress and the higher cadmium load, when it changed. The statistically significant higher index of phenotypic plasticity for protease correlated with lower variability. Protease isoforms at the same cadmium treatments differed between genotypes, while some protease isoforms from one egg-mass differed between cadmium treatments. Owing to the low sensitivity and plasticity of mass change during exposure to cadmium, as well as its small influence, we concluded that larval mass is not a good indicator of cadmium presence in food. We suggest that proteases, with further research, might be a suitable indicator of dietary cadmium contamination, as well as nutriment utilization during heavy metal stress.
镉的摄取主要通过食物进行。舞毒蛾幼虫被暴露于浓度分别为10和30μg Cd/克干粮的膳食镉中（分别为无观察到效应浓度和最低观察到效应浓度），用于急性和慢性处理及恢复。我们确定，仅在以30μg Cd/干粮进行慢性处理期间金属污染才会使体重下降，且在去除镉3天后体重没有恢复。在急性和慢性处理后的最低观察到效应浓度下检测到蛋白酶活性显著降低。在环境压力和更高镉负荷期间，当蛋白酶发生变化时，其在适应性性状（体重）方面表现出增强的可塑性。蛋白酶表型可塑性的统计学显著更高指数与更低变异性相关。相同镉处理下的蛋白酶同工型在基因型之间存在差异，而来自一个卵块的一些蛋白酶同工型在镉处理之间也存在差异。由于暴露于镉期间体重变化的敏感性和可塑性较低，以及其影响较小，我们得出结论，幼虫体重不是食物中镉存在的良好指标。我们建议，经过进一步研究，蛋白酶可能是膳食镉污染以及重金属胁迫期间营养利用的合适指标。
