Insecticide-induced hormesis in insects

杀虫剂引起的昆虫毒物兴奋作用

• 批准号: RGPIN-2015-04639
• 负责人: Cutler, Gerald
• 金额: $ 2.33万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=648451
• 关键词: Insecticide; induced; hormesis; insects

Very low doses of insecticide can have stimulatory effects on insects. This biphasic toxicological phenomenon, whereby a chemical may be toxic at high doses but stimulatory at low doses is called `hormesis'. We previously showed that exposure of insects to mild doses of insecticide can greatly stimulate population growth and alter expression of genes involved in stress response and development. However, we still have a relatively poor understanding of the ecological and evolutionary significance of insecticide-induced hormesis for insects. The long-term goal of the research program is to understand the adaptive significance and potential practical applications of hormetic stress responses in insects. This will serve as a centerpiece for the following short-term objectives/questions:******- Does insecticide-induced hormesis "prime" insects to better cope with additional stressors they may later experience, and does this persist across generations? ***- Does insecticide-induced hormesis lead to increased mutation rates and detoxifying enzymes that accelerate development of insecticide resistance? ***- Can exposure to low doses of pesticide, as seen with other stressors, stimulate reproduction or learning in bees?***- Can exposure to low doses of insecticide stimulate reproduction in biocontrol agents (natural enemies) over multiple generations, without affecting overall fitness?******Different insect-insecticide models will be used to test hypotheses in laboratory or greenhouse settings, measuring molecular, biochemical, individual, and population endpoints. All experiments will involve training of undergraduate and graduate students, or post-doctoral fellows. ******The proposed work is original and poised to have high impact internationally. Few studies have tested if mild stress primes organisms for more stress later in life, and we know of no experiments that have studied the problem over multiple generations. We also are not aware of experiments examining the link between hormesis and pesticide resistance, despite there being good reasons to suspect a linkage exists. This is significant given the likely role of hormesis in pest population resurgences and ecological backlash. Though many have studied how to apply hormesis in human health, little effort has explored this with other organisms. The proposed experiments with biocontrol agents are novel and could provide insight on how to improve production of natural enemies in commercial rearing facilities. Our experiments with bees are innovative and have the potential to have high impact for those involved in the pesticide-pollinator debate. Many pesticides are certainly toxic to pollinators, but the possibility of pesticide-induced hormetic responses in bees has been overlooked. If our predictions hold, our results could be a "toxicological awakening" for scientists, legislators, and citizens engaged in pollinator risk assessment.**

极低剂量的杀虫剂对昆虫有刺激作用。这种两相毒理现象，即一种化学物质在高剂量时可能是有毒的，但在低剂量时是刺激的，这种现象被称为“兴奋效应”。我们之前的研究表明，昆虫暴露在中等剂量的杀虫剂下可以极大地刺激种群增长，并改变参与应激反应和发育的基因的表达。然而，我们对杀虫剂诱导的昆虫兴奋的生态和进化意义的了解仍然相对较少。该研究计划的长期目标是了解昆虫节律应激反应的适应意义和潜在的实际应用。这将作为以下短期目标/问题的中心：*--杀虫剂诱导的兴奋作用是否能更好地应对它们以后可能经历的额外应激源，这种情况是否会在世代中持续下去？*--杀虫剂诱导的兴奋作用是否会导致突变率增加，解毒酶加速发展对杀虫剂的抗药性？*--暴露在低剂量杀虫剂下，是否会刺激蜜蜂的繁殖或学习？*--暴露在低剂量杀虫剂下，是否会刺激生防剂(天敌)在多个世代中的繁殖，在不影响整体适应性的情况下？*将使用不同的昆虫-杀虫剂模型在实验室或温室环境中测试假设，测量分子、生化、个体和种群终点。所有实验都将涉及本科生和研究生或博士后研究员的培训。*拟议的工作具有原创性，并有望在国际上产生很高的影响。很少有研究测试温和的压力是否会让生物体在以后的生活中承受更多的压力，我们也不知道有什么实验对这个问题进行了多次世代的研究。我们也没有意识到检验兴奋作用和农药耐药性之间联系的实验，尽管有充分的理由怀疑存在联系。考虑到刺激作用在害虫种群复苏和生态反弹中的可能作用，这一点意义重大。虽然许多人已经研究了如何将兴奋作用应用于人类健康，但很少有人在其他生物上探索这一点。拟议的生防剂实验是新颖的，可以为如何在商业饲养设施中提高天敌的产量提供见解。我们用蜜蜂进行的实验是创新的，有可能对那些参与杀虫剂和传粉者争论的人产生很大影响。许多杀虫剂对传粉者当然是有毒的，但杀虫剂引起蜜蜂兴奋反应的可能性被忽视了。如果我们的预测成立，我们的结果可能是科学家、立法者和从事传粉者风险评估的公民的“毒物学觉醒”。