Construction of intestinal-targeting curcumin liposomes based on four microalgae polysaccharides from different sources and evaluation of their efficacy against colitis in mice

Curcumin’s poor solubility and low bioavailability, along with inadequate colon-targeting of conventional IBD drugs, limit therapeutic efficacy. Here, four polysaccharides (LXZ, LYYZ, LZ, GXM) were extracted respectively from four different microalgae and used to modify curcumin-loaded liposomes. All formulations showed particle sizes 160 nm and good dispersibility. LXZ-modified liposomes (LXZ-Lip@Cur) exhibited the highest encapsulation efficiency and superior storage stability, enabling sustained release in simulated intestinal fluid and enhanced gastrointestinal retention and preferential accumulation in the colon in vivo. In DSS-induced ulcerative colitis mice, LXZ-Lip@Cur significantly alleviated symptoms and colonic injury. Mechanistically, it upregulated the expression of colonic tight junction proteins, suppressed excessive inflammation, attenuated oxidative stress, and modulated gut microbiota dysbiosis. These results indicated microalgal polysaccharide-functionalized liposomes as a promising oral platform for IBD therapy.