Relieving Effect of Extract on DSS-Induced Colitis by Regulating Immunity, Antioxidant Function, Gut Microbiota, and Bile Acid Metabolism in Mice.

, a traditional Chinese herbal medicine, possesses antibacterial, antiviral, and anti-inflammatory properties. The aim of this experiment was to investigate the therapeutic effect of extraction (AOE) in treating colitis induced by dextran sulfate sodium (DSS) in mice. The in vitro antioxidant activity of AOE was evaluated by assessing its iron reduction capacity and scavenging capacity towards 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals (·OH). The protective effect of AOE on colitis in mice was determined by monitoring key indicators such as body weight, colon length, and survival rate in mice, as well as by assessing the expression of colon-related genes and cytokine levels. We evaluated the impact of AOE on intestinal microbiota by measuring the 16s sequencing of cecal contents and bile acid metabolism. The results showed that the iron reduction capacity of AOE was positively correlated with its concentration. The half-maximal inhibitory concentrations (IC) for scavenging DPPH and hydroxyl radicals were 3.126 mg/mL and 6.139 mg/mL, with a 95% confidence interval of 95%. In vivo studies demonstrated that AOE reduced DSS-induced colitis in mice by increasing the colon length, enhancing antioxidant enzyme activity, inhibiting inflammatory cell infiltration, suppressing the formation of TNF-α and IL-6, and reducing malondialdehyde (MDA) levels. qPCR analysis revealed that AOE reversed the down-regulation of mRNA expression, and altered the composition of cecal microbiota, thus mitigating DSS-induced colitis. AOE plays a crucial role in alleviating colitis in mice and effectively improves DSS-induced colitis, highlighting its potential as a therapeutic agent for inflammatory bowel diseases.