Relative Oral Bioavailability Study of Liposomal Curcumin

Background: Curcumin is a naturally derived yellow polyphenolic compound from the rhizome Curcuma longa. Curcumin modulates various signalling pathways, such as Cyclooxygenase-2 (COX-2), Matrix metallopeptidases (MMPs), glutathione, protein kinase C, ATPase, nuclear Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-kb), Activator protein 1 (AP-1), P-glycoprotein 1 (P-gp), Multidrug resistance-associated proteins (MRP-1, MRP-2), Receptor tyrosine-protein kinase (ErbB2), Alpha-1-acid glycoprotein AGP), Cyclin D1 etc. Curcumin, as a free drug, has a short plasma half-life because it is rapidly metabolised in the liver. Its oral bioavailability is extremely poor, and hence Curcumin is classified as a class IV compound in the BCS system.

Materials and Methods: Authors of the current study have formulated Liposomal Curcumin and conducted a Relative Oral Bioavailability Study of Liposomal Curcumin in comparison with plain Curcumin in rats. The treatment group was given Curcumin 25% I lipo at the dose of 500 mg/kg body weight and the control group was given plain Curcumin 500 mg/ kg body weight of the rats.

Observations: Oral administration of Liposomal Curcumin showed rapid absorption (t_max =15 min) with Peak plasma concentration (C_max), Area under Curve (AUC) and half-life (t_1/2) of 42.3 ng/ml, 244 ng.h/ml and 5.5 h, respectively. In the control group, the Curcumin levels were below the level of quantitation (5.43 ng/ml).

Conclusion: This study shows that Liposomal Curcumin has higher bioavailability as compared to the marketed formulations of Curcumin. Further extensive clinical studies are needed to prove efficacy of Liposomal Curcumin in various human applications.