Preliminary exploration of inulin and inulin liposome on DSS-induced colitis remission

Inulin and its fermentation products benefit gastrointestinal health. However, it remains unclear whether inulin can directly act on inflammatory cells and treat ulcerative colitis (UC). The purpose of this study was to preliminarily evaluate and compare the potential therapeutic effects of inulin and its liposomes (LS) in UC treatment. The particle size, zeta potential, and encapsulation efficiency of prepared inulin LS were 293.80 ± 4.979 nm, −14.23 ± 1.00 mV and 54.2 ± 2.87%, respectively. In vitro, inulin directly inhibited IL-6 secretion on activated RAW264.7 cells, especially inulin LS, which might show stronger inflammation clearance by increased cell uptake. Moreover, the symptoms of dextran sulfate sodium-induced colitis mice were significantly alleviated in inulin and inulin LS treatment, including decreased disease activity index, myeloperoxidase expression and proinflammatory cytokines secretion, and histopathological recovery. The therapeutic effect of inulin LS was more pronounced compared to the same dose of inulin. Surprisingly, inulin LS treatment at a lower dose (60 mg/kg) showed a similar remission as the sulfasalazine (200 mg/kg). In summary, our findings revealed that inulin encapsulated in liposomes can play a similar role to conventional drugs, and the dose is much lower. These may provide new ideas for the delivery and utilization of polysaccharides and offer a safer and more promising approach to UC therapy.