title: Arrest of oogenesis in the bug Rhodnius prolixus challenged with the fungus Aspergillus niger is mediated by immune response-derived PGE2.
abstract: In this work we characterized the immune response of the insect Rhodnius prolixus to a direct injection into the hemocoel of the non-entomopathogenic fungus Aspergillus niger, and evaluated its consequences on host oogenesis. These animals were able to respond by mounting effective cellular and humoral responses to this fungus; these responses were shown, however, to have reproductive fitness costs, as the number of eggs laid per female was significantly reduced. The disturbance of egg formation during infectious process correlated with an elevation in the titer of hemolymph prostaglandin E2 48 h post-challenge. Administration of Zymosan A as an immunogenic non-infectious challenge produced similar effects on phenoloxidase and prophenoloxidase activities, oocyte development and prostaglandin E2 titer, precluding the hypothesis of an effect mediated by fungal metabolites in animals challenged with fungus. Ovaries at 48 h post-challenge showed absence of vitellogenic ovarian follicles, and the in vivo administration of prostaglandin E2 or its receptor agonist misoprostol, partially reproduced this phenotype. Together these data led us to hypothesize that immune-derived prostaglandin E2 raised from the insect response to the fungal challenge is involved in disturbing follicle development, contributing to a reduction in host reproductive output and acting as a host-derived adaptive effector to infection.
authors.affiliation: Programa de Biologia Celular e Parasitologia, IBCCF, Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, RJ, Brazil.
authors.forename: Marcelo Neves de
authors.initials: MN
authors.lastname: Medeiros
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Belmonte
authors.forename: Bruno César C
authors.initials: BC
authors.lastname: Soares
authors.forename: Luciano Neves de
authors.initials: LN
authors.lastname: Medeiros
authors.forename: Cláudio
authors.initials: C
authors.lastname: Canetti
authors.forename: Celio G
authors.initials: CG
authors.lastname: Freire-de-Lima
authors.forename: Clarissa Menezes
authors.initials: CM
authors.lastname: Maya-Monteiro
authors.forename: Patrícia Torres
authors.initials: PT
authors.lastname: Bozza
authors.forename: Igor C
authors.initials: IC
authors.lastname: Almeida
authors.forename: Hatisaburo
authors.initials: H
authors.lastname: Masuda
authors.forename: Eleonora
authors.initials: E
authors.lastname: Kurtenbach
authors.forename: Ednildo A
authors.initials: EA
authors.lastname: Machado
mesh_terms: D000220:Adaptation, Biological / Q000276:immunology*; D000704:Analysis of Variance; D000818:Animals; D001234:Aspergillus niger / Q000276:immunology*; D015232:Dinoprostone / Q000097:blood; D005260:Female; D013058:Mass Spectrometry; D009866:Oogenesis / Q000187:drug effects / Q000502:physiology*; D010053:Ovary / Q000187:drug effects*; D012239:Rhodnius / Q000187:drug effects / Q000276:immunology* / Q000382:microbiology; D015054:Zymosan / Q000633:toxicity
chemical_list: D015054:Zymosan; D015232:Dinoprostone