Ndo Cyrille, Kopya Edmond, Irving Helen, Wondji Charles
Department of parasitology, Centre for Research in Infectious Disease (CRID), Yaoundé, P.O. Box 13591, Cameroon.
Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, P.O. Box 24157, Cameroon.
Wellcome Open Res. 2019 Mar 19;4:52. doi: 10.12688/wellcomeopenres.15061.2. eCollection 2019.
Malaria control heavily relies on insecticide-based interventions against mosquito vectors. However, the increasing spread of insecticide resistance is a major threat. The extent to which such resistance, notably metabolic resistance, interferes with the development of the parasite and its impact on overall malaria transmission remains poorly characterized. Here, we investigated whether glutathione S-transferase-based resistance could influence development in . females were infected with gametocytes and midguts were dissected at day 7 post infection for detection/quantification of oocysts. Infection parameters were compared between individual with different L119F-GSTe2 genotypes, and the polymorphism of the GSTe2 gene was analyzed in infected and uninfected mosquito groups. Overall, 403 mosquitoes were dissected and genotyped. The frequency of the L119F-GSTe2 resistance allele was significantly higher in non-infected (55.88%) compared to infected (40.99%) mosquitoes (Fisher's exact test, P<0.0001). Prevalence of infection was significantly higher in heterozygous and homozygous susceptible genotypes (P<0.001). However, homozygous resistant and heterozygous mosquitoes exhibited significantly higher infection intensity (P<0.01). No association was observed between the GSTe2 polymorphism and the infection status of mosquitoes. Altogether, these results suggest that GSTe2-based metabolic resistance may affect the vectorial competence of resistant mosquitoes to infection, by increasing its permissiveness to infection.
疟疾防控严重依赖于针对蚊媒的基于杀虫剂的干预措施。然而，杀虫剂抗性的日益传播是一个重大威胁。这种抗性，尤其是代谢抗性，对疟原虫发育的干扰程度及其对总体疟疾传播的影响仍未得到充分表征。在此，我们研究了基于谷胱甘肽S-转移酶的抗性是否会影响疟原虫在按蚊中的发育。将雌性按蚊感染配子体，并在感染后第7天解剖中肠以检测/定量卵囊。比较了具有不同L119F-GSTe2基因型个体之间的感染参数，并分析了感染和未感染蚊群中GSTe2基因的多态性。总体而言，解剖并对403只蚊子进行了基因分型。未感染蚊子中L119F-GSTe2抗性等位基因的频率（55.88%）显著高于感染蚊子（40.99%）（Fisher精确检验，P<0.0001）。杂合子和纯合敏感基因型的感染率显著更高（P<0.001）。然而，纯合抗性和杂合蚊子表现出显著更高的感染强度（P<0.01）。未观察到GSTe2多态性与蚊子感染状态之间的关联。总之，这些结果表明，基于GSTe2的代谢抗性可能通过增加对疟原虫感染的易感性来影响抗性按蚊对疟原虫感染的媒介能力。
