Biochemical and histochemical study on the intestinal mucosa of the common carp Cyprinus carpio L., with special consideration of mucin glycoproteins

Abstract

The biochemical and histochemical properties of intestinal mucin glycoproteins of virus and parasite-free common carp Cyprinus carpio were investigated. The presence of carbohydrates in mucin glycoproteins could be demonstrated by histochemical methods, but generally, no obvious differences in specific staining for mucin glycoproteins were observed in contrast to biochemical techniques. Biochemical staining methods displayed differences in structure and composition of intestinal glycoproteins. Released intestinal glycoproteins contained two types of mucin glycoproteins: type 1 mucins displayed a size of >2000 kDa, and were highly glycosylated, while type 2 mucins ranged between 700 and 70 kDa, and were weakly glycosylated. In epithelial (intracellular) glycoproteins, mainly N-acetyl-a-galactosamine and mannose were found, while in luminal (extracellular) glycoproteins in addition sialic acid was evident. Fucose was not detected. Thus, structure and composition of intestinal glycoproteins of common carp were similar to those found in mammals.

Effect of β-Glucans in Diets on Growth, Survival, Digestive Enzyme Activity, and Immune System and Intestinal Barrier Gene Expression for Tropical Gar (Atractosteus tropicus) Juveniles

“…Herein, it was reported that the expression of MUC2 increased directly with the increase of β-glucans in the diet, which might suggest that the ability to regulate the expression of mucin is a benefit for responding to pathogens. However, a decrease in expression was observed in A. tropicus fed 2.0% β-glucans in the diet, which indicated that high concentrations of this immunostimulant inhibited the expression of MUC2 (a quadratic response), which is in accordance with reports in C. carpio, where the increase in the mucus layer, rich in oligosaccharide-modified glycoproteins was observed with the administration of this immunostimulant [49]. Likewise, studies in mammals, evaluating galactooligosaccharides and fructooligosaccharides, reported a positive effect on the mucin content in the intestinal mucosa [50,51].…”

Histological structures of the accessory glands of the digestive system in adult farmed African catfish (Clarias gariepinus B.)

“…The presence of PAS positive mucous cells suggests transport of molecules across the cell membrane. The strong AB positive mucous cells at the base of the main pancreatic duct mucosal fold may suggest and adaptation for protection against pathogens as more bacteria may accumulation at this location more than at the tip [31].…”

Adhesion to brown trout skin mucus, antagonism against cyst adhesion and pathogenicity to rainbow trout of some inhibitory bacteria against Saprolegnia parasitica

“…Adhesion was expressed as the percentage of fluorescence recovered in the second measurement relative to the fluorescence at T0. Binding of the mucus to the plate was confirmed by a lectin-binding assay as described by Neuhaus et al (2007), using Dolichos biflorus lectin (DBA, Sigma).…”