Hunan Kouweiwang Group Co., Ltd.

Ulcerative colitis (UC) is an inflammatory bowel disease and has emerged as a public health challenge worldwide. The present study aimed to isolate polysaccharide from fresh Areca catechu L. (FAP1a) and to investigate its potential mechanism for ameliorating UC symptoms in a mouse model of UC. The results indicated that the molecular weight of FAP1a was approximately 65 kDa and consisted of arabinose, mannose and galactose, with the main chain probably consisting of →3,6)-β-Gal-(1 → and →2,4,6)-β-Man-(1→. FAP1a effectively attenuated weight loss and colonic tissue damage in mice. FAP1a modulated gut microbial composition by increasing the abundance of beneficial bacteria such as Ligilactobacillus, Dubosiella, Ruminococcus and Lactobacillus. Meanwhile, FAP1a upregulated the expression of beneficial metabolites including L-glutamate, D-mannose, and D-tagatose mainly through the alanine, aspartate and glutamate metabolism and galactose metabolism pathways. The above results elucidated that FAP1a could alleviate UC symptoms through modulation of the gut microbial structure and serum metabolites. These findings highlight the potential of FAP1a as a novel therapeutic agent for UC and provided insights into the potential mechanisms underlying its therapeutic effects.

Being the first line of defense, intestinal mucosal immunity serves as in maintaining immune homeostasis among organisms. This study investigated the impact of the areca inflorescence polysaccharide (AFP) on intestinal mucosal immunity and elucidated the mechanisms responsible for the immunomodulatory effects of AFP. The immunosuppression mouse model was established using the cyclophosphamide. The intestinal mucosal status was evaluated based on the intestinal integrity, chemical and mucosal immune barriers, and intestinal flora. According to the findings, AFP enhances intestinal integrity by up-regulating the expression of tight junction proteins and reinforcing the chemical barrier through increased mucin-2, β-defensins, and SIgA expression and secretion. Furthermore, AFP restores the mucosal immune barrier by regulating immune cells within Peyer's patches and lamina propria. AFP also reverses the intestinal flora balance and regulates its metabolism. Additionally, AFP effectively modulates the immune response in the spleen and peripheral blood. Together, these results indicated that AFP repairs mucosal damage and restores mucosal immunity, thereby preserving the immune homeostasis of organisms.