Dietary Yeast Cell Wall Extract Alters the Proteome of the Skin Mucous Barrier in Atlantic Salmon (Salmo salar): Increased Abundance and Expression of a Calreticulin-Like Protein

Abstract

In order to improve fish health and reduce use of chemotherapeutants in aquaculture production, the immunomodulatory effect of various nutritional ingredients has been explored. In salmon, there is evidence that functional feeds can reduce the abundance of sea lice. This study aimed to determine if there were consistent changes in the skin mucus proteome that could serve as a biomarker for dietary yeast cell wall extract. The effect of dietary yeast cell wall extract on the skin mucus proteome of Atlantic salmon was examined using two-dimensional gel electrophoresis. Forty-nine spots showed a statistically significant change in their normalised volumes between the control and yeast cell wall diets. Thirteen spots were successfully identified by peptide fragment fingerprinting and LC-MS/MS and these belonged to a variety of functions and pathways. To assess the validity of the results from the proteome approach, the gene expression of a selection of these proteins was studied in skin mRNA from two different independent feeding trials using yeast cell wall extracts. A calreticulin-like protein increased in abundance at both the protein and transcript level in response to dietary yeast cell wall extract. The calreticulin-like protein was identified as a possible biomarker for yeast-derived functional feeds since it showed the most consistent change in expression in both the mucus proteome and skin transcriptome. The discovery of such a biomarker is expected to quicken the pace of research in the application of yeast cell wall extracts.

Biological and Ecological Roles of External Fish Mucus: A Review

“…The use of high-throughput techniques such as proteomics allows for the pursuit of comprehensive comparative studies to better understand fish mucus dynamics. Proteomics studies have cast light on fish mucus dynamics of infected fish [181][182][183], overcrowding [184], chronic stress [185], and fish exposed to different diets [186].…”

Impacts of Dietary Protein and Prebiotic Inclusion on Liver and Spleen Gene Expression in Hy-Line Brown Caged Layers

“…There is increasing interest in the inclusion of YCW as prebiotic in animal feed due to its property as a functional feed [18]. The presence of various potentially beneficial components in YCW makes it potentially useful for improving performance and health.…”

“…The presence of various potentially beneficial components in YCW makes it potentially useful for improving performance and health. In aquaculture, for example, their role in reducing sea-louse parasitism to improving immunity has been investigated [18,20] In dogs, the inclusion of YCW helped improve gut health and generated positive immunomodulatory effects [31]. A study on broilers showed improved intestinal immunoglobulin A and immune responses in feeds with YCW inclusion [32].…”

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

“…Besides changes in the skin mucus proteome, i.e. differentially expressed proteins have been studied after infection [ 24 – 27 ], from handling or crowding stress [ 28 , 29 ], after parental care [ 30 ] and more recently after administration of different dietary supplements [ 29 , 31 ]. However, despite the relevancy to fish health, there are no studies regarding the changes on the skin mucosae following injury so far.…”