Butyrate has been attracting attention for the suppression of inflammatory bowel disease (IBD). However, clinical trials of butyrate for IBD treatment have resulted in controversial outcomes, likely owing to the adverse effect of butyrate on the intestinal epithelium that was observed at high butyrate concentrations. Herein, we propose polyvinyl butyrate (PVBu) nanoparticles (NPs) as butyrate donors for delivery to the lower part of the intestine for the treatment of colitis. The PVBu NPs suppressed the inflammatory activation of macrophages in vitro, although sodium butyrate inversely further activated macrophages. Oral administration of NPs did not change the luminal concentration of free butyrate; however, NPs showed a therapeutic effect on a colitis mouse model. In addition, incorporation of vitamin D3 into the NPs enhanced the therapeutic effect on colitis. Hence, PVBu NPs are a promising therapeutic for IBD treatment, not only as a butyrate donor but also as a carrier for hydrophobic drugs like vitamin D3.
Keywords: butyrate; inflammatory bowel disease; nanoparticles; polyvinyl butyrate; vitamin D3.