Dextran sulfate-coated curcumin nanocrystals for the treatment of DSS-induced ulcerative colitis in mice.

Ulcerative colitis is an inflammatory disease that primarily involves intestinal inflammation and epithelial damage. The nano-targeted drug delivery system delivers drugs to the disease site, exerting effects such as inhibiting inflammatory response and reducing reactive oxygen species expression, thereby promoting recovery from ulcerative colitis. In this experiment, dextran sulfate-coated curcumin nanocrystals (NBD) were prepared for the oral treatment of ulcerative colitis (UC). NBD not only significantly enhances the water solubility and stability of curcumin but also possesses the ability of sustained release and targeting inflammatory macrophages. The sustained release effect of NBD was demonstrated by in vitro release experiments. In simulated gastric fluid, the cumulative release amount of NBD at 2 h was 21.99 ± 1.93 %, while in simulated colonic fluid, the cumulative release amount of NBD at 12 h was 84.98 ± 2.02 %. The ability of NBD to target inflammatory macrophages was verified through the transwell system, rat one-way intestinal perfusion experiment and in vivo imaging system. The in vitro and in vivo (mice) anti-inflammatory and antioxidant capacities of NBD were validated using immunofluorescence experiment, ELISA kits and reactive oxygen species-related detection kits. The results indicated that NBD could reduce inflammatory responses, promote macrophage polarization and inhibit oxidative stress. In addition, the therapeutic effect of NBD was further confirmed in this experiment by the clostridium perfringens-induced necrotizing enteritis model in chickens. In conclusion, NBD might be a potential pharmaceutical preparation for the treatment of UC.