Grape seed proanthocyanidin extract alleviates inflammation in experimental colitis mice by inhibiting NF‐κB signaling pathway

Abstract Ulcerative colitis (UC) is a complex inflammatory disease of colorectum that induces abnormal immune responses and severely affects the quality of life of the patients. Grape seed proanthocyanidin extract (GSPE) exerts anti‐inflammatory and antioxidant functions in many inflammatory diseases. The objective of this study was to investigate the potential therapeutic effects and underlying mechanisms of GSPE in UC using a dextran sodium sulfate (DSS)‐induced mouse UC model and a lipopolysaccharide (LPS)‐stimulated RAW264.7 macrophage model. In this study, we found that the GSPE markedly prevented DSS‐induced weight loss and colon length shortening in UC mice. Further investigations showed that GSPE significantly attenuated the expression of pro‐inflammatory cytokines TNF‐α, IL‐6, and IL‐1β, and elevated the expression of anti‐inflammatory cytokine IL‐10 in the colon tissues and serum of DSS‐induced colitis mice by suppressing NF‐κB signaling pathway. Furthermore, LPS‐induced inflammation in RAW264.7 cells was also reversed by GSPE. Taken together, our results confirm that GSPE can ameliorate inflammatory response in experimental colitis via inhibiting NF‐κB signaling pathway. This study advances the research progress on a potentially effective therapeutic strategy for inflammatory bowel diseases.