TLR4 and ulcerative colitis: As a metabolic derivative of berberine, dihydroberberine has been shown to enhance the intestinal barrier function by blocking the TLR4/MyD88/NF-κB signaling pathway, reducing the levels of pro-inflammatory cytokines in the colon, and upregulating the expression levels of intestinal tight junction proteins and mucins, thereby effectively alleviating dextran sulfate sodium-induced ulcerative colitis.