Platycodin D targets ZNF70 to inhibit NLRP3 inflammasome and STAT3 signaling pathway to ameliorate colitis.

Background: UC is a chronic inflammatory bowel disease that can be severe enough lead to bowel perforation and even colorectal cancer. The current treatments for UC have several limitations, highlighting the urgent need for the development of novel therapeutic agents. Recent research has shown that ZNF70 plays a crucial role in colitis-associated colorectal cancer. PLD, as one of the main active ingredients of Platycodon grandiflorum, can attenuate DSS-induced intestinal inflammation. In this study, we aimed to investigate the mechanism by which PLD works to treat UC.

Materials And Methods: Prediction of targets for PLD and colitis using network pharmacology. In vitro, overexpression of ZNF70/knockdown of ZNF70 plasmid was transfected into THP-1 cells and cells were induced with a combination of LPS and ATP. The effect of PLD on NLRP3 inflammasome and STAT3 signaling pathway was detected. In in vivo experiments, DSS induced acute colitis in mice, and ZNF70 lentivirus was injected into the tail vein to knock down ZNF70 to study the effect of PLD on colitis. A series of experimental methods such as WB, PCR, IP and IF were used in the study.

Results: Through a series of in vitro experiments, it was found that PLD downregulated the expression of NLRP3 inflammasome and STAT3 signaling pathway through ZNF70. In DSS-induced colitis in vivo experiments, knockdown of ZNF70/addition of PLD reduced the expression of inflammatory factors and attenuated the inflammatory response. HPLC analysis also showed no accumulation of PLD in the five organs.

Conclusion: This work demonstrates for the first time that PLD targets ZNF70 to regulate the activation of NLRP3 inflammasome and the STAT3 signaling pathway in macrophages, revealing an unknown property of PLD for the treatment of colitis and providing a new basis for targeting ZNF70 to improve the efficacy of treatment in colitis and other diseases.