title: Deregulated balance of omega-6 and omega-3 polyunsaturated fatty acids following infection by the zoonotic pathogen Streptococcus suis.
abstract: Streptococcus suis is an important swine pathogen and an emergent zoonotic pathogen. Excessive inflammation caused by S. suis is responsible for early high mortality in septic shock-like syndrome cases. Polyunsaturated fatty acids (PUFAs) may contribute to regulating inflammatory processes. This study shows that mouse infection by S. suis is accompanied by an increase of arachidonic acid, a proinflammatory omega-6 (ω-6) PUFA, and by a decrease of docosahexaenoic acid, an anti-inflammatory ω-3 PUFA. Macrophages infected with S. suis showed activation of mitogen-activated protein kinase pathways and cyclooxygenase-2 upregulation. Fenretinide, a synthetic vitamin A analog, reduced in vitro expression of inflammatory mediators. Pretreatment of mice with fenretinide significantly improved their survival by reducing systemic proinflammatory cytokines during the acute phase of an S. suis infection. These findings indicate a beneficial effect of fenretinide in diminishing the expression of inflammation and improving survival during an acute infection by a virulent S. suis strain.
authors.affiliation: Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, Québec, Canada.
authors.forename: Claude
authors.initials: C
authors.lastname: Lachance
authors.forename: Mariela
authors.initials: M
authors.lastname: Segura
authors.forename: Maria C
authors.initials: MC
authors.lastname: Dominguez-Punaro
authors.forename: Gabriella
authors.initials: G
authors.lastname: Wojewodka
authors.forename: Juan B
authors.initials: JB
authors.lastname: De Sanctis
authors.forename: Danuta
authors.initials: D
authors.lastname: Radzioch
authors.forename: Marcelo
authors.initials: M
authors.lastname: Gottschalk
mesh_terms: D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology; D002460:Cell Line; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000097:blood / Q000378:metabolism*; D043371:Fatty Acids, Omega-6 / Q000097:blood / Q000378:metabolism*; D017313:Fenretinide / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D013290:Streptococcal Infections / Q000097:blood / Q000378:metabolism*; D017011:Streptococcus suis / Q000502:physiology*; D015047:Zoonoses
chemical_list: D016588:Anticarcinogenic Agents; D016207:Cytokines; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D017313:Fenretinide