Institute of Systematics and Ecology of Animals, Siberian Branch of the Russian Academy of Sciences, Frunze Str. 11, Novosibirsk 630091, Russia.
Chemosphere. 2011 Sep;85(1):92-6. doi: 10.1016/j.chemosphere.2011.05.039. Epub 2011 Jun 14.
In this study, we tested the effects of dietary nickel on the activity of glutathione S-transferase (GST), esterases, phenoloxidase, and encapsulation in the haemolymph of larvae of the greater wax moth Galleria mellonella. We also explored the effects of dietary nickel on larval resistance to infection by the fungus Beauveria bassiana. Larvae fed a low dose of nickel (10 μg g(-1)) had significantly higher GST, phenoloxidase activity and encapsulation responses than controls fed on a nickel-free diet. We also found that larvae fed a sublethal dose of nickel (50 μg g(-1)) had increased GST, esterase activity and encapsulation rates but decreased phenoloxidase activity. Although, a sublethal dose of dietary nickel enhanced innate immunity, we found that this reduced resistance against the real pathogen. Our results suggest that enhanced immunity and detoxification enzyme activity of insects may not be beneficial to resistance to fungal infection. It appears that there is a trade off between different resistance mechanisms in insects under different metal treatments.
在这项研究中，我们测试了膳食镍对欧洲玉米螟幼虫血淋巴中谷胱甘肽 S-转移酶（GST）、酯酶、酚氧化酶和包被作用的影响。我们还探讨了膳食镍对幼虫抵抗白僵菌感染的影响。与喂食无镍饮食的对照组相比，摄入低剂量镍（10μg g(-1)）的幼虫的 GST、酚氧化酶活性和包被反应显著升高。我们还发现，摄入亚致死剂量镍（50μg g(-1)）的幼虫的 GST、酯酶活性和包被率增加，但酚氧化酶活性降低。尽管膳食镍的亚致死剂量增强了先天免疫，但我们发现这降低了对真正病原体的抵抗力。我们的结果表明，昆虫的增强免疫力和解毒酶活性可能不利于对真菌感染的抵抗力。在不同的金属处理下，昆虫的不同抵抗机制似乎存在权衡。
