Chronic hyperosmotic stress inhibits renal Toll-Like Receptors expression in striped catfish (Pangasianodon hypophthalmus, Sauvage) exposed or not to bacterial infection.
Toll-like Receptors (TLRs) are the first innate receptors in recognizing pathogen-associated molecular patterns. In fish, upregulation of toll-like receptors during infection has been largely demonstrated while the effects of abiotic stressors on their expression remain poorly investigated. In this study, striped catfish were submitted during 20 days to three salinity profiles (freshwater, low saline water, saline water), followed by injection of a bacterial strain of Edwardsiella ictaluri. The expression of TLRs 1, 3, 4, 5, 7, 9, 19, 21, and 22 was measured in kidney at different time points in non infected and infected striped catfish. Infection induced overexpression of TLRs 1, 3, 4, 5, 7, 21 and 22. With elevated salinity, the expression of all TLRs, except TLR5, was severely decreased, particularly after bacterial infection. The TLRs responsiveness of striped catfish facing bacterial disease and salinity stress and possible consequences on striped catfish immune response's efficiency are discussed.
University of Namur, Research Unit in Environmental and Evolutionary Biology, Namur, Belgium. Electronic address: melodie.schmitz@unamur.be.
Mélodie
M
Schmitz
University of Namur, Research Unit in Environmental and Evolutionary Biology, Namur, Belgium.
Sébastien
S
Baekelandt
University of Namur, Research Unit in Environmental and Evolutionary Biology, Namur, Belgium.
Sandrine
S
Bequet
University of Namur, Research Unit in Environmental and Evolutionary Biology, Namur, Belgium.
Patrick
P
Kestemont
D000818:Animals; D002397:Catfishes / Q000276:immunology* / Q000378:metabolism; D020610:Edwardsiella ictaluri; D004756:Enterobacteriaceae Infections / Q000662:veterinary; D005393:Fish Diseases / Q000276:immunology; D029941:Fish Proteins / Q000096:biosynthesis / Q000276:immunology; D007668:Kidney / Q000276:immunology / Q000378:metabolism; D009994:Osmolar Concentration; D054712:Salinity; D013312:Stress, Physiological / Q000276:immunology*; D051193:Toll-Like Receptors / Q000096:biosynthesis* / Q000276:immunology
D029941:Fish Proteins; D051193:Toll-Like Receptors
Infection; Salinity; Striped catfish; Toll-like Receptors