Insecticidal Activity and Expression of Cytochrome P450 Family 4 Genes in Aedes albopictus After Exposure to Pyrethroid Mosquito Coils

Abstract

Mosquito coils are insecticides commonly used for protection against mosquitoes due to their toxic effects on mosquito populations. These effects on mosquitoes could induce the expression of metabolic enzymes in exposed populations as a counteractive measure. Cytochrome P450 family 4 (CYP4) are metabolic enzymes associated with a wide range of biological activities including insecticide resistance. In this study, the efficacies of three commercial mosquito coils with different pyrethroid active ingredients were assessed and their potential to induce the expression of CYP4 genes in Aedes albopictus analyzed by real-time quantitative PCR. Coils containing 0.3 % D-allethrin and 0.005 % metofluthrin exacted profound toxic effects on Ae. albopictus, inducing high mortalities (≥90 %) compared to the 0.2 % D-allethrin reference coil. CYP4H42 and CYP4H43 expressions were significantly higher in 0.3 % D-allethrin treated mosquitoes compared to the other treated populations. Short-term (KT50) exposure to mosquito coils induced significantly higher expression of both genes in 0.005 % metofluthrin exposed mosquitoes. These results suggest the evaluated products provided better protection than the reference coil; however, they also induced the expression of metabolic genes which could impact negatively on personal protection against mosquito.

Allelic variants of cytochrome P450 monooxygenases: Constitutive and insecticide-mediated expression in a Malaysian strain of the dengue vector, Aedes aegypti (Diptera: Culicidae)

“…Differential expression of CYP4H28v2 and CYP4H31v2 in A. aegypti larvae in this study was dependent on the type of insecticide and exposure time. This pattern is consistent with previous studies on other insects, including species of Aedes (Poupardin et al, 2010;Liu et al, 2011;Huang et al, 2013;Avicor et al, 2014). CYP4H28v2 and CYP4H31v2 were strongly induced by permethrin after a 6 h exposure.…”

“…Insecticides can induce P450s and the over-expression of P450s in insecticide-resistant and treated strains sometimes provide cues for identifying putative insecticide detoxifying P450s (Amenya et al, 2008;Poupardin et al, 2010;Huang et al, 2013). Some studies on the induction potential of insecticides on P450s use sub-lethal concentrations as in this present study and other previous works (Poupardin et al, 2010;Avicor et al, 2014) to record the adaptive response of insects to toxic compounds. Differential expression of CYP4H28v2 and CYP4H31v2 in A. aegypti larvae in this study was dependent on the type of insecticide and exposure time.…”

Dose‐, time‐and lipophilicity‐dependent silver(I)–N‐heterocyclic carbene complexes: Synthesis, characterization and interaction with plasmid and Aedes albopictus DNA

“…The bond distance of Ag1 with C1 (and its symmetry equivalent, C1 i ) is 2.077(2) Å (Table ), while the bond distance for tetrafluoroborate counterpart is 2.089 Å. The internal ring angle at the carbene centre (N1–C1–N2) is 106.6(2)°, which agrees well with reported complexes . The π–π interactions with a separation of 3.826(5) Å are observed between two adjacent complexes, resulting in the formation of a two‐dimensional supramolecular structure.…”

“…The most widespread vector control practice is insecticide‐based control. However, dengue vectors have evolved resistance to insecticides due to various mechanisms, reducing the potency of insecticide‐based vector control and jeopardising efforts to halt the spread of dengue.…”

Selection of reference genes for quantitative real‐time polymerase chain reaction normalization inBradysia odoriphaga(Diptera: Sciaridae)

“…Therefore, reliable reference genes are crucial for accurately interpreting the expression of target genes (Artico et al 2010). Housekeeping genes have been conventionally used for reference genes in RT-qPCR analysis, including 18S rRNA, Actin, Tubulin, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), elongation factor-1 (EF-1), ribosomal protein (RP) and TATA binding protein (TBP) (Ponton et al 2011;Zhong et al 2013;Avicor et al 2014;Cardoso et al 2014;Zhai et al 2014). Nevertheless, some studies have reported that the expression of universal reference genes can show great variation across different tissues and developmental stages and under different experimental treatments Collins et al 2014;Dai et al 2017).…”