Pyoderma gangrenosum is strongly associated with inflammatory bowel disease and exhibits pathergy, occurring at sites ofprevious minor trauma. A patient is presented with a 21 year history of extensive ulcerative colitis, who developed pyoderma gangrenosum and arthralgia while receiving high dose corticosteroids for active ulcerative colitis. The arthralgia exhibited pathergy affecting particularly the left temporomandibular joint, which was stressed by an asymmetric bite, and the left elbow, which had been fractured many years previously. This prompted the hypothesis that neutrophils in this condition may be marginated, as a result of increased stickiness ofeither the neutrophil or the vascular endothelium. The introduction of heparin therapy was associated with rapid resolution ofthe arthralgia, pyoderma gangrenosum, and ulcerative colitis. (Gut 1995; 37: 585-588)

Background Gut dysbiosis is associated with various health conditions, including inflammatory bowel disease (IBD). IBD is a chronic inflammatory condition of the gastrointestinal tract that has no cure. One potential approach for managing IBD is the use of natural products that have anti-inflammatory and gut microbiota-regulating effects. Bergenin is a bioactive compound obtained from plants, and its therapeutic potential in IBD has not been extensively studied.Objective This study aimed to investigate the potential of bergenin in regulating gut microbiota dysbiosis induced by colitis in a mouse model.Methods and Results In this study, a colitis mouse model was established by exposing mice to 2.5% DSS for 7 days. The clinical symptoms were assessed, and the composition of the gut microbiota was analyzed using 16S rRNA gene sequencing. The results revealed that the treatment with bergenin (50 mg/Kg/d) significantly improved clinical symptoms compared to the control group (P < 0.05). The degree of histological damage was also lower in the bergenin-treated group than in the control group (P < 0.05). The dysbiosis of the gut microbiota caused by DSS was significantly attenuated by bergenin treatment compared to the control group (P < 0.01). The treatment with bergenin led to increased species diversity and relative abundance of the genus Barnesiella.Conclusion The study findings suggest that bergenin has the potential to maintain gut health by suppressing dysbiosis of the gut microbiota and ameliorating clinical symptoms caused by DSS. Bergenin may be considered a potential therapeutic agent for managing IBD in the future. However, further studies are needed to investigate the long-term effects of bergenin on gut microbiota and its safety before clinical use.