Encapsulated hesperetin modulates inflammatory responses in an in vitro intestinal immune co-culture model

In vitro cell models are an effective way to evaluate the biological activities of functional compounds. Hesperetin (HST) is a flavanone with various potential health-related benefits, and encapsulation improved its stability and bioavailability. This study aimed to investigate the anti-inflammatory effects of encapsulated HST using different delivery systems, including β-cyclodextrin (CD), nanoliposomes (NL), and NL coated with chitosan (CH) and carrageenan (CGN). A Caco-2 and THP-1 co-culture model characterized by direct cell-to-cell contact was developed, and these delivery systems were digested in vitro and subsequently tested on this model. The addition of lipopolysaccharide (LPS) in the model resulted in high secretion of the pro-inflammatory cytokines (IL-8, TNF-α, and IL-1β), the upregulation of the phenotype genes (CD68 and CD80) and the inflammation-related genes (MYD88, NFκB, and COX-2), marking the differentiation of M0 macrophages into M1 macrophages. Among the delivery systems, HST encapsulated in CH and CGN coated NL (CGN-CH-NL-HST) was the most effective in suppressing the production of IL-8 and expression of MYD88 and COX-2 in the inflammatory co-culture model. Metabolomic data showed that the M1 macrophage metabolic profile was changed by applying free HST and encapsulated HST, mostly in glycolysis and amino acid metabolism. Encapsulated HST in the CGN-CH-NL delivery system showed anti-inflammatory activity in the Caco-2 and THP-1 direct co-culture model, suggesting a potential of encapsulated bioactive compounds in treating inflammatory bowel disease.