Detoxification Mechanisms in Insects

The Insecticide Imidacloprid Decreases Nannotrigona Stingless Bee Survival and Food Consumption and Modulates the Expression of Detoxification and Immune-Related Genes

“…Our findings nevertheless differ from previous research that found no significant differences in daily syrup consumption of honey bees exposed to imidacloprid concentrations less than 20 ng/mL [50], or that found that bees even preferred and consumed more food containing neonicotinoid pesticides [82,83]. The toxicity and sensitivity of different stages, populations, and species of insects may be related to the type of pesticide, mode of action, duration of exposure, pesticide dose or concentration, and timing of exposure [43,51,84]. As a result, understanding how native stingless bees respond to and defend against agrochemicals is crucial in allowing recommendations to be formulated for their use in the tropics.…”

“…Insects have evolved various detoxification mechanisms to survive natural plant and environmental toxins (xenobiotics), which they also employ in response to insecticides [43]. Insecticide detoxification is one such mechanism; in this case, detoxification is carried out by enzymes that metabolize xenobiotics, including pesticides [44,45].…”

“…Insecticide detoxification is one such mechanism; in this case, detoxification is carried out by enzymes that metabolize xenobiotics, including pesticides [44,45]. Though detoxification may allow insects to overcome insecticides, the degree of detoxification differs greatly among insect species, which results in differing toxicity among different stages, populations, and species of insects [43]. Pesticides also have an effect on the immune systems of insects, which include both cellular and humoral responses [46].…”

Identifying candidate detoxification genes in the ecdysteroid kinase-like (EcKL) and cytochrome P450 gene families inDrosophila melanogasterby integrating evolutionary and transcriptomic data

“…In animals, detoxification is carried out by collections of enzyme and transporter systems present in a number of organs and tissues throughout the body, which were originally conceptualised as a series of “phases” that result in the sequential modification (phase I), conjugation (phase II) and excretion (phase III) of toxins. This “canonical model” of detoxification, as well as the typical reactions expected in each phase, were defined in the context of mammalian pharmacological research (Williams, 1959), and have been adopted by researchers of other animal taxa, including insects (Berenbaum and Johnson, 2015; Chahine and O’Donnell, 2011; Yu, 2008). However, one concern about this canonical model is that a mammalian lens may limit our understanding of insect detoxification, as the lineages leading to arthropods and vertebrates diverged approximately 600 m.y.a.…”

“…To validate this approach, we examine the cytochrome P450s (henceforth P450s), which are a large multigene family of enzymes that largely function as monooxygenases and catalyse phase I detoxification reactions such as hydroxylation, although a subset also catalyse a wider variety of reactions, including dealkylation, epoxidation and reduction (Bernhardt, 2006). P450s are an established detoxification family in virtually all animals, including insects (Heidel-Fischer and Vogel, 2015; Yu, 2008), and the number of P450 genes per genome in insects varies dramatically, from 38 in the fig wasp Ceratosolen solmsi to 222 in the little fire ant Wasmannia auropunctata (Rane et al, 2019). It has been suggested that diversity in the size of the P450 gene family may be linked to differences in detoxification capacity between taxa (Calla et al, 2017; Rane et al, 2019; 2016), although this has not been rigorously studied.…”