RESUMEN
A previous proteomic study examining the plasma acute-phase response of rainbow trout to sterile inflammation highlighted an unidentified 9.5-kDa spot using 2D-PAGE, which was dramatically increased. The 15 amino acid sequence obtained from this protein spot allowed rapid amplification of cDNA ends PCR to generate a 443-bp nucleotide sequence that was 98.6% similar to type-4 ice-structuring protein LS-12 from Atlantic salmon Salmo salar Linnaeus. Quantitative reverse translation PCR and an ELISA were used to measure gene expression and plasma concentrations of LS-12 following experimental intraperitoneal injection of rainbow trout with either 106 or 108 colony-forming units (CFU) of Flavobacterium psychrophilum. There was no significant change in the plasma concentration of LS-12 up to 15 days post-infection in any group. Hepatic LS-12 gene expression was significantly reduced at 3 and 6 days (p < 0.001) post-infection in fish injected with 108 CFU of F. psychrophilum relative to control fish, while branchial or head kidney expression was unchanged. Infected fish had significantly increased hepatic gene expression of serum amyloid A, confirming an acute-phase response. Under the conditions used, LS-12 is not a positive acute-phase protein in rainbow trout.
Asunto(s)
Reacción de Fase Aguda/veterinaria , Enfermedades de los Peces/microbiología , Proteínas de Peces/genética , Infecciones por Flavobacteriaceae/veterinaria , Oncorhynchus mykiss/microbiología , Reacción de Fase Aguda/microbiología , Animales , Proteínas de Peces/sangre , Infecciones por Flavobacteriaceae/microbiología , Flavobacterium/patogenicidad , Reacción en Cadena de la Polimerasa , ProteómicaRESUMEN
Anionic polyacrylamide (PAM) products are commonly used to remove suspended materials from turbid waters and to help mitigate soil erosion. In the present study, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to 3 mg/L to 300 mg/L of 10 commercially available PAM products (Clearflow Water Lynx Polymer Log and Clearflow Soil Lynx Granular Polymer; Clearflow Enviro Systems Group), and gill histological parameters were measured following either 7 d or 30 d of polymer exposure. A cationic polymer product (≤0.38 mg/L MagnaFloc 368; Ciba Specialty Chemical) was also tested for comparison. Mild gill lesions were observed in fish exposed to polymer products. Lamellar fusion, interlamellar hyperplasia, epithelial lifting, mucous cell metaplasia, and cell counts of epithelial swelling and necrosis/apoptosis were minimal in fish exposed to environmentally relevant concentrations of anionic polymer (≤30 mg/L). Gill morphology was largely unaffected by exposure to concentrations up to 300 mg/L of many PAM products. Several anionic polymer products noticeably affected gill tissue by increasing epithelial hypertrophy, interlamellar hyperplasia, mucous cell metaplasia, and the frequency of necrotic cells. The severity of the lesions lessened with time, suggesting that fish may have experienced a short-term irritant effect. Similar levels of gill pathology were frequently observed in fish exposed to cationic polymer MagnaFloc 368 despite the concentration being 1000-fold lower than that of the PAM products. These observations highlight the increased toxicity of cationic polymers to aquatic life compared with anionic PAMs.
Asunto(s)
Resinas Acrílicas/toxicidad , Branquias/efectos de los fármacos , Branquias/ultraestructura , Oncorhynchus mykiss/anatomía & histología , Contaminantes Químicos del Agua/toxicidad , Animales , Aniones/toxicidad , Oncorhynchus mykiss/crecimiento & desarrolloRESUMEN
The ontogeny of lysozyme activity, intelectin, TLR-5M and TLR-5S gene expression and intelectin localization was examined in rainbow trout (Oncorhynchus mykiss) reared from oocytes immersed for 3h prior to fertilization in either ovarian fluid alone (CC) or cortisol-enriched ovarian fluid at either 100 ng mL(-1) (C1) or 1000 ng mL(-1) (C2) [final oocyte cortisol concentrations were ~3, ~5, and ~7.5 ng oocyte(-1) for the CC, C1 and C2 treatment groups, respectively]. Lysozyme activity was elevated in the cortisol-treated groups from the zygote until 13-days post fertilization (dpf), but was not affected at 21-dpf. Intelectin levels were elevated in both cortisol treatment groups at 12-hpf (2-cell stage) and then suppressed between 36- and 48-hpf. Intelectin mRNA transcript levels were elevated in both cortisol treatment groups in oocytes; there were no differences among treatment groups at 1- and 5-dpf, and suppressed in the C2 treatment group in 13-dpf and 26-dpf. TLR-5 mRNA transcripts were higher in cortisol-treated oocytes prior to fertilization; TLR-5S mRNA was more abundant than TLR-5M mRNA. The ontogeny of the gene expression patterns, and the gene, lectin and lysozyme responses to oocyte cortisol adjustments suggest an important role of innate immune systems in the early cleavage stages of embryonic cells.