Dietary arginine supplementation mitigates the soybean meal induced enteropathy in juvenile turbot,Scophthalmus maximusL.

Abstract

A 12‐week feeding trial was conducted to investigate the protective effects of arginine on the intestinal health of juvenile turbot (Scophthalmus maximus L.) fed high doses of dietary soybean meal. Sextuple replicates of 30 fish were fed each of four isonitrogenous and isolipidic experimental diets: fish‐meal‐based diet (FM); FM with 40% fish meal protein replaced by soybean meal protein (SBM); SBM+1% arginine (ARG1) and SBM+2% arginine (ARG2). Turbot‐fed SBM showed typical soybean meal‐induced enteropathy, characterized by an increase in the thickness of lamina propria, as well as significant decreases in the absorptive surface and activities of intestinal brush border membrane enzymes and Na+, K+‐ATPase. On the contrary, fish‐fed ARG1 showed enhanced intestinal mucosal barrier function in terms of the enhanced gene expression of anti‐inflammatory cytokine and barrier‐forming tight junction proteins, as well as depressed gene expression of pro‐inflammatory cytokines and pore‐forming tight junction proteins. Fish‐fed AGR2 showed intermediate intestinal performances between SBM and AGR1. Dietary arginine (1%) also significantly regulated the expression of AMP‐activated protein kinase α1 (AMPKα1), myosin light chain kinase (MLCK) and nuclear transcription factor‐κB p65 (NF‐κB p65), and these regulations correlated well with its regulations on intestinal mucosal barrier related genes at all sampling time‐points. In conclusion, arginine supplementation (1%) in diet for turbot mitigated the soybean meal‐induced enteropathy by enhancing the intestinal mucosal barrier function. The activation of AMPKα1 signalling molecule as well as the suppression of NF‐κB p65 and MLCK signalling molecules may mediate the beneficial effects of arginine.

Dynamics of Intestinal Inflammatory Cytokines and Tight Junction Proteins of Turbot (Scophthalmus maximus L.) During the Development and Recovery of Enteritis Induced by Dietary β-Conglycinin

“…In addition, another study in turbot showed that diet with 6% 7S (purity, ∼75.87%) could damage the intestinal histology after a 4-week feeding trial (Gu et al, 2016). Also, enteritis was observed after a 12-week feeding trial in turbot fed diet with 37.9% soybean meal (about 6% 7S) (Chen Z. et al, 2018;Liu et al, 2018). Based on these researches in turbot and the purpose of our study, a level of 8% 7S (purity, 81.3%) in diet was chosen to ensure that the 7S-induced enteritis can occur in turbot in a short time.…”

“…The secretion of inflammatory cytokines and the reassembly of tight junction structure are thought to be important in the initiation and/or development of enteritis (Hee, 2015). Evidences in grass carp (Ctenopharyngodon idella) (Luo et al, 2014;Chen K. et al, 2018;Wu et al, 2018), Jian carp (Cyprinus carpio) (Jiang et al, 2015), and turbot (Scophthalmus maximus) (Chen Z. et al, 2018;Liu et al, 2018) have shown that the upregulated gene expression of pro-inflammatory cytokines occurs along with the down-regulated gene expression of tight junction proteins in enteritis. However, the nature of inflammatory cytokines and tight junction dynamics during enteritis remains poorly understood.…”

“…During rapid growth of aquaculture, soybean meal has been widely used in fish feed due to the limited supply and high price of fish meal. However, application of soybean meal in feeds for marine fish generally induced enteritis (Li et al, 2017;Chen Z. et al, 2018;Liu et al, 2018). 7S is known to be a main Abbreviations: 7S, β-conglycinin; DAO, diamine oxidase; FER, feed efficiency ratio; FI, feed intake; FM, fish meal; GAPDH, glyceraldehyde-3phosphatedehydrogenase; GC, goblet cell; H&E, hematoxylin and eosin; IFN-γ, interferon-γ; IL-1β, interleukin-1β; IL-8, interleukin-8; IL-22, interleukin-22; LP, lamina propria; MF, mucosal fold; MLC, myosin II regulatory light chain; MLCK, myosin light chain kinase; MM, muscularis mucosa; MV, microvilli; NF-κB, nuclear factor-kappa B; SGR, specific growth rate; SML, submucous layer; TGF-β, transforming growth factor-β; TNF-α, tumor necrosis factor-α; ZO-1, zonula occludens-1.…”

Effects of arginine supplementation on growth performance and plasma arginine, ornithine and citrulline dynamics of rainbow trout, Oncorhynchus mykiss

“…Modulation of lipid and glucose metabolism, and insulin signalling pathway were also demonstrated in blunt snout bream (Liang et al, ). Furthermore, a collaborative study of the Ocean University of China and Institute of Hydrobiology demonstrated that supplemental dietary arginine effectively mitigated enteropathy induced by dietary soybean meal in juvenile turbot (Chen et al, ). This example clearly shows that supplemental arginine in plant‐based diet is one of the promising approaches of achieving sustainable fish farming with functional nutrients.…”

Dietary citric acid supplementation alleviates soybean meal-induced intestinal oxidative damage and micro-ecological imbalance in juvenile turbot, Scophthalmus maximus L

“…Soybean meal is a potential alternative protein source used in aqua‐feed; however, in some fish such as Atlantic salmon, common dentex, and turbot soy protein could inhibit fish growth in a dose‐dependent manner through negatively influencing the intestinal health (Antonopoulou, Chouri, Feidantsis, Lazou, & Chatzifotis, ; Bakke‐Mckellep et al, ; Chen et al, ; Reveco, Øverland, Romarheim, & Mydland, ). Oxidative stress was proposed as one of the reasons for intestinal barrier dysfunction induced by soybean meal (Jiang et al, ; Zhang et al, ).…”