There were multiple mechanisms involved in the alleviation of DSS-induced colitis by H4-2 and H9-3, including restoring the imbalanced microbial barrier by regulating the structure of microbial flora, increasing short chain fatty acid levels, repairing the physical barrier of the intestine by increasing MUC2 content and TJ protein concentration, repairing the immune barrier of mice intestines by reducing the release of pro-inflammatory factors (TNF-α, IL-1β, IL-6, IL-8), and inhibiting the NF-κB signaling pathway (Figure 11). The gene discussed is MUC2; the disease is colitis.