Effects of dietary soy isoflavone and soy saponin on growth performance, intestinal structure, intestinal immunity and gut microbiota community on rice field eel (Monopterus albus)

Abstract

Background: Soy iso avone and soy saponin are heat-stable glycosides present in soybean meal, which is the major factor restrict soy protein using in aquatic feed. This study is aimed to conduct that dietary soy iso avone and soy saponin on growth performance, intestinal structure, intestinal immunity and gut microbiota community on rice eld eel (Monopterus albus), and revealed its mechanism. Results: In current study, dietary 1g/kg soy iso avone, 2g/kg soy saponin and their mixed feed decreased growth of M. albus. Dietary 1g/kg soy iso avone signi cantly increased serum alkaline phosphatase (P < 0.05), dietary 2g/kg soy saponin remarkably declined intestinal immunoglobulin M (P < 0.05). Dietary 1g/kg soy iso avone and 2g/kg soy saponin mixed feed signi cantly decreased intestinal complement 3, complement 4 and immunoglobulin M, amounts of intestinal goblet cells per root and shannon of gut microbiota (P < 0.05). Dietary 1g/kg soy iso avone, 2g/kg soy saponin and their mixed feed down regulated intestinal tight junction protein (Interleukin-12, Interleukin-15, Tight junction protein ZO-2-like) and anti-in ammatory (Interleukin-10, Transforming growth factor beta 2) mRNA expression, up regulated pri-in ammatory factors (Interleukin-1 β, Interleukin-6, Interleukin-8, Interleukin-12 and Interleukin-15) mRNA expression. Conclusion: Based on the current results, dietary soy iso avone and soy saponin could damage the intestinal structure and changes gut bacteria community of M. albus, and destroyed the intestinal barrier, eventually induced intestinal in ammatory occurring, soy iso avone and soy saponin mixed feed has more serious effect than they single supplemented.

Methionine-Mediated Regulation of Intestinal Structure and Lipid Transport in the Rice Field Eel (Monopterus albus)

“…In addition, in this paper, compared with M0, we also observed that intestinal villus height and muscular thickness were remarkably increased in M8, and amounts of goblet cells per root in M8 were increased, while intestinal crypt depth remarkably decreased; besides, lipid droplet in intestinal villus and mucosal layer in the M8 (8 g/kg) group were more than that in M0 (0 g/kg) in this study, which meant that the function of intestinal absorption was declined and the intestinal barrier was damaged [29], also including lipid. Our previous study showed a similar result as dietary soy isoflavone and soy saponin damage the intestinal barrier and decrease intestinal function [23].…”

“…The stomach and intestine from five fish in each cage were taken for histometric evaluation. The method of making slides and observing the intestinal sections stained with H&E referenced our previous manuscript [23]. The intestine was sectioned (8 μm) using a cryostat microtome, stained with Oil red O [24].…”

Effects of Dietary Glycinin on Oxidative Damage, Apoptosis and Tight Junction in the Intestine of Juvenile Hybrid Yellow Catfish, Pelteobagrus fulvidraco ♀ × Pelteobaggrus vachelli ♂

“…This might be due to the fact that glycinin, as a foreign antigen, caused immune injury and inflammation, and then inflammatory factors destroyed intestinal epithelial tissue proteins. A great number of studies have proved that the destruction of the intestinal barrier function is directly related to inflammatory factors [ 16 , 43 , 44 , 45 ].…”

High Dietary Histamine Induces Digestive Tract Oxidative Damage in Juvenile Striped Catfish (Pangasianodon hypophthalmus)

“…Intestinal innate immunity plays an essential role in maintaining intestinal health, which constitutes the first line of defense against colonization by disease-causing microorganisms [ 46 ]. Intestinal immune activity is accomplished by the synergistic action of multiple immune enzymes and immunologically active substances, including immunoglobulins M (IgM), lysozyme, and the complement (C3, C4) [ 47 , 48 ]. In this study, dietary histamine (above 120 mg/kg) significantly decreased intestinal C3, C4, and IgM contents, suggesting that high-dose dietary histamine is detrimental to the innate immunity of striped catfish, thereby disrupting intestinal health.…”