Journal article
The Effect of Insecticide Synergists on the Response of Scabies Mites to Pyrethroid Acaricides
PLoS Neglected Tropical Diseases, Vol.3(1), e354
2009
Abstract
Background: Permethrin is the active component of topical creams widely used to treat human scabies. Recent evidence has demonstrated that scabies mites are becoming increasingly tolerant to topical permethrin and oral ivermectin. An effective approach to manage pesticide resistance is the addition of synergists to counteract metabolic resistance. Synergists are also useful for laboratory investigation of resistance mechanisms through their ability to inhibit specific metabolic pathways. Methodology/Principal Findings: To determine the role of metabolic degradation as a mechanism for acaricide resistance in scabies mites, PBO (piperonyl butoxide), DEF (S,S,S-tributyl phosphorotrithioate) and DEM (diethyl maleate) were first tested for synergistic activity with permethrin in a bioassay of mite killing. Then, to investigate the relative role of specific metabolic pathways inhibited by these synergists, enzyme assays were developed to measure esterase, glutathione S-transferase (GST) and cytochrome P450 monooxygenase (cytochrome P450) activity in mite extracts. A statistically significant difference in median survival time of permethrin-resistant Sarcoptes scabiei variety canis was noted when any of the three synergists were used in combination with permethrin compared to median survival time of mites exposed to permethrin alone (p<0.0001). Incubation of mite homogenates with DEF showed inhibition of esterase activity (37%); inhibition of GST activity (73%) with DEM and inhibition of cytochrome P450 monooxygenase activity (81%) with PBO. A 7-fold increase in esterase activity, a 4-fold increase in GST activity and a 2-fold increase in cytochrome P450 monooxygenase activity were observed in resistant mites compared to sensitive mites. Conclusions: These findings indicate the potential utility of synergists in reversing resistance to pyrethroid-based acaricides and suggest a significant role of metabolic mechanisms in mediating pyrethroid resistance in scabies mites.
Details
- Title
- The Effect of Insecticide Synergists on the Response of Scabies Mites to Pyrethroid Acaricides
- Authors
- C Pasay (Author) - University of QueenslandL Arlian (Author) - Wright State University, United StatesM Morgan (Author) - Wright State University, United StatesR Cunning (Author) - New South Wales Department of Primary IndustriesL Rossiter (Author) - New South Wales Department of Primary IndustriesD C Holt (Author) - Charles Darwin UniversityShelley F Walton (Author) - Charles Darwin UniversityS Beckham (Author) - Monash UniversityJ McCarthy (Author) - University of Queensland
- Publication details
- PLoS Neglected Tropical Diseases, Vol.3(1), e354; 8
- Publisher
- Public Library of Science
- Date published
- 2009
- DOI
- 10.1371/journal.pntd.0000354
- ISSN
- 1935-2727
- Copyright note
- Copyright © 2009 Pasay et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This published version is reproduced in accordance with this policy.
- Organisation Unit
- University of the Sunshine Coast, Queensland; School of Health and Sport Sciences - Legacy
- Language
- English
- Record Identifier
- 99449532802621
- Output Type
- Journal article
Metrics
52 File views/ downloads
560 Record Views
InCites Highlights
These are selected metrics from InCites Benchmarking & Analytics tool, related to this output
- Collaboration types
- Domestic collaboration
- International collaboration
- Web Of Science research areas
- Infectious Diseases
- Parasitology
- Tropical Medicine
UN Sustainable Development Goals (SDGs)
This output has contributed to the advancement of the following goals:
Source: InCites