Chronic wounds alter the proteome profile in skin mucus of farmed gilthead seabream

Abstract

BackgroundSkin and its mucus are known to be the first barrier of defence against any external stressors. In fish, skin wounds frequently appear as a result of intensive culture and also some diseases have skin ulcers as external clinical signs. However, there is no information about the changes produced by the wounds in the mucosae. In the present paper, we have studied the alterations in the proteome map of skin mucus of gilthead seabream during healing of experimentally produced chronic wounds by 2-DE followed by LC-MS/MS. The corresponding gene expression changes of some identified skin proteins were also investigated through qPCR.ResultsOur study has successfully identified 21 differentially expressed proteins involved in immunity and stress processes as well as other metabolic and structural proteins and revealed, for the first time, that all are downregulated in the skin mucus of wounded seabream specimens. At transcript level, we found that four of nine markers (ighm, gst3, actb and krt1) were downregulated after causing the wounds while the rest of them remained unaltered in the wounded fish. Finally, ELISA analysis revealed that IgM levels were significantly lower in wounded fish compared to the control fish.ConclusionsOur study revealed a decreased-expression at protein and for some transcripts at mRNA levels in wounded fish, which could affect the functionality of these molecules, and therefore, delay the wound healing process and increase the susceptibility to any infection after wounds in the skin of gilthead seabream.

Effects of Experimental Terrestrialization on the Skin Mucus Proteome of African Lungfish (Protopterus dolloi)

“…Previous studies have shown changes in the skin proteome composition of teleost fish (aquatic vertebrates) in response to infection ( 41 , 42 ), stress ( 43 – 45 ), wounding ( 46 ), or dietary administration of immunostimulants ( 44 , 45 , 47 ). However, most of these studies adopted a two-dimensional (2-D) gel electrophoresis approach where selected spots were then analyzed by peptide fragment fingerprinting and LC-MS/MS.…”

Quantitative shotgun proteomics distinguishes wound-healing biomarker signatures in common carp skin mucus in response to Ichthyophthirius multifiliis

“…In this study, carp keratin I cytoskeletal 18 protein was upregulated (11.4-fold) after I. multifiliis infection, while keratin I cytoskeletal 18-like was downregulated (3.5-fold) at 9 dpe. Keratin has been identified in the skin mucus of gilthead seabream [ 32 ], Atlantic cod [ 33 ], and European sea bass [ 1 ]. Keratin is a cytoskeletal protein whose primary function is to protect cells from mechanical and non-mechanical injuries.…”

“…Keratin turnover is dependent on the ubiquitin–proteasome pathway, and its expression levels can be altered upon injury. Recently, it has been reported that the expression of keratin I and II was downregulated in cod mucus, following a vibrio infection, and in gilthead seabream in response to chronic wounds [ 1 , 5 ]. The carp keratin I cytoskeletal 18 proteins were differentially regulated after I. multifiliis infection, suggesting they may play different sequential and/or site dependant roles in carp immune response aimed at protection against the parasite.…”

“…Intensive fish farming raises the incidence of injuries and diseases. Skin mucus acts as a mechanical, physical, chemical, biological, and immunological barrier against any external stressor [ 1 ]. Skin mucus has become a novel area of research and a true indicator of the immune status of fish.…”

“…Therefore, they are used as a model for tissue regeneration in humans. Cordero et al [ 1 ] investigated the modification of the skin mucus proteome after inducing chronic wounds in gilthead seabream ( Sparus aurata ) and found that structural proteins, which are involved in tissue repair, were downregulated. However, little information is available on the proteomic modification of fish skin mucus in response to tissue damage caused by invading pathogens.…”