Linderanine C regulates macrophage polarization by inhibiting the MAPK signaling pathway against ulcerative colitis

Ulcerative colitis (UC) is a chronic non-specific inflammatory disease involving the mucosa and submucosa of the rectum and colon. Lindera aggregate (Sims) Kosterm is a traditional Chinese herb used for thousands of years in the treatment of gastrointestinal diseases. Previously, we have demonstrated that the extracts of Lindera aggregate have good anti-UC effects, but their pharmacodynamic active components have not been fully clarified. Therefore, we explored the therapeutic effect of Linderanine C (LDC), a characteristic component of Lindera aggregata , on UC and its mechanism in this study. Firstly, we found that LDC could significantly reduce the disease activity index of UC and improve shortened colon and pathological changes in vivo . Colon tissue transcriptomics suggested that the anti-UC effect of LDC might be related to its anti-inflammatory activity. Cellular experiments revealed that LDC could inhibit the expression of the M1 cell marker CD86 in RAW264.7 cells, reduce the production of inflammatory mediators such as IL-6 and TNF-α, and have good anti-inflammatory activity in vitro . Cellular transcriptomics reveal the potential involvement of the MAPK signaling pathway in the anti-inflammatory effect of LDC. The co-culture assay confirmed that LDC could significantly reduce inflammation-mediated intestinal epithelial cell injury. In conclusion, LDC was able to inhibit macrophage M1 polarization and reduce inflammatory mediator production by inhibiting the MAPK signaling pathway, effectively improving UC. Linderanine C regulate the MAPK signaling pathway, inhibits macrophage M1 polarization, reducing inflammatory mediator levels, and has anti-inflammatory and anti-UC pharmacological effects. • LDC effectively improves ulcerative colitis induced by DSS. • LDC regulates inflammation by inhibiting the MAPK pathway. • LDC protects intestinal epithelial cells by its anti-inflammatory effects.