Prevention of Hypercholesterolemia with “Liposomes in Microspheres” Composite Carriers: A Promising Approach for Intestinal-Targeted Oral Delivery of Astaxanthin

Cardiovascular diseases are caused by hypercholesterolemia. Astaxanthin (AST) has been reported to exhibit antioxidant and anti-inflammatory properties. However, its bioavailability is poor because of low solubility and instability. In order to improve the bioavailability of AST, we developed an intestinal-responsive composite carrier termed as "liposomes in micropheres" incorporating N-succinyl-chitosan (NSC)-poly(ethylene glycol) (PEG) liposomes that functionalized by neonatal Fc receptors (FcRn) into hydrogels of sodium alginate (SA) and carboxymethyl chitosan (CMCS). In the AST NSC/HSA-PEG liposomes@SA/CMCS microspheres, the AST's encapsulation efficiency (EE) was 96.26% (w/w) and its loading capacity (LC) was 6.47% (w/w). AST NSC/HSA-PEG liposomes had stability in the gastric conditions and achieved long-term release of AST in intestinal conditions. Then, AST NSC/HSA-PEG liposomes@SA/CMCS bind to intestinal epithelial cell targets by the neonatal Fc receptor.