Fig. 1. Butyrate-conjugated polymeric micelles transit to the distal GI tract to deliver butyrate and mediate therapeutic effects.
a, Polymeric micelle systems were designed with butyrate conjugated to a polymer with a hydrophobic block, which makes up the inside of the micelle, and a hydrophilic outer block. b, Mice were intragastrically gavaged with neutral (NtL-ButM) or negatively charged (Neg-ButM) micelles containing butyrate. Sodium butyrate (NaBut) was used as a control. c, After intragastric administration, NaBut is absorbed in the stomach, but polymer micelles transit to and release butyrate in the distal small intestine (NtL-ButM) and caecum/colon (Neg-ButM). d, In the distal GI tract, butyrate is cleaved from the micelles’ polymer backbone. The backbone is excreted while local butyrate has various therapeutic effects in the intestine and mesenteric lymph nodes in murine models of food allergy and colitis. Graphic created with BioRender.com.