Departamento de Biologia Celular, Universidade de Brasília, Brasília, Brazil; Núcleo de Pesquisa em Morfologia e Imunologia Aplicada, NuPMIA, Faculdade de Medicina, Universidade de Brasília, Brasília, Brazil.
Laboratório de Ecologia Molecular, Embrapa Recursos Genéticos e Biotecnologia, Brasília, Brazil.
Insect Biochem Mol Biol. 2021 Jul;134:103581. doi: 10.1016/j.ibmb.2021.103581. Epub 2021 Apr 25.
Insect diapause shares many biochemical features with other states of metabolic depression, including the suppression of global metabolism, reorganization of metabolic pathways and improved stress resistance. However, little is known about the biochemical changes associated with the diapause phenotype in tropical insects. To investigate biochemical adaptations associated with tropical diapause, we measured the activities of metabolic and antioxidant enzymes, as well as glutathione levels, in the sunflower caterpillar Chlosyne lacinia at different times after initiation of diapause (<1, 20, 40, 60, and 120 days) and after arousal from diapause. Biochemical changes occurred early in diapausing animals, between the first 24 h and 20 days of diapause. Diapausing animals had reduced oxidative capacity associated with a decrease in the activities of peroxide-decomposing antioxidant enzymes. There was no sign of redox imbalance either during diapause or after recovery from diapause. Noteworthy, glutathione transferase and isocitrate dehydrogenase-NADP activities sharply increased in diapausing animals and stand out as diapause-associated proteins. The upregulation of these two enzymes ultimately indicate the occurrence of Preparation for Oxidative Stress in the tropical diapause of C. lacinia.
昆虫休眠与其他代谢抑制状态有许多生化特征共享，包括整体代谢的抑制、代谢途径的重组以及对压力的抵抗力提高。然而，关于与热带昆虫休眠相关的生化变化知之甚少。为了研究与热带休眠相关的生化适应，我们在向日葵毛虫 Chlosyne lacinia 进入休眠（<1、20、40、60 和 120 天）后以及从休眠中苏醒后的不同时间测量了代谢和抗氧化酶的活性以及谷胱甘肽水平。生化变化发生在休眠动物的早期，即在休眠的前 24 小时到 20 天之间。休眠动物的氧化能力降低，与过氧化物分解抗氧化酶的活性下降有关。在休眠或从休眠中恢复后，也没有出现氧化还原失衡的迹象。值得注意的是，谷胱甘肽转移酶和异柠檬酸脱氢酶-NADP 的活性在休眠动物中急剧增加，作为休眠相关蛋白而突出。这两种酶的上调最终表明在 C. lacinia 的热带休眠中发生了氧化应激的准备。
