Modified chitosan derivative micelle system for natural anti-tumor product gambogic acid delivery

Abstract
A chitosan derivative micelle system was developed as the delivery system for a novel anti-tumor drug, gambogic acid (GA). The physicochemical and pharmaceutical properties of GA-loaded micelles (GA-M) were evaluated compared with the formulation GA-L-arginine (GA-L) injection, which entered phase I clinical trials. The results showed that GA-M had high GA-loading rate (29.8 ± 0.17%), high entrapment efficiency (63.8 ± 0.52%), and small particle size (108.2 ± 0.8 nm). After i.v. administration at the dose of 4 mg/kg, the area under concentration-time curve (AUC) and elimination half-life (T1/2β) of GA-M were all increased by 1.7-fold compared with GA-L in rat. Biodistribution study indicated that ∼ 67% of GA in the GA-M group was distributed in the liver, while the value of the GA-L group was ∼ 55%. Additionally, GA amount in the kidney was greatly reduced in the GA-M group. Also, GA-M was shown to reduce the acute toxicity after i.v. administration in mice compared with GA-L. The present study indicated that GA was rapidly eliminated from the blood and transferred to the tissues, especially the liver. Moreover, GA acute toxicity and irritation to vein were decreased.