Enhancing Curcumin Oral Bioavailability Through Nanoformulations.

Curcumin is a promising therapeutic agent that exhibits manifold therapeutic activities. However, it is challenging to study curcumin as it exhibits poor aqueous solubility and low permeability and it is a substrate for P-glycoprotein (P-gp). It is readily metabolized in the body, but many active metabolites of curcumin have been identified that could also be exploited for therapy. Strategies for the oral bioenhancement of curcumin to leverage the potential of curcumin as a therapeutic molecule are discussed here in light of these challenges. A brief discussion of conventional bioenhancement strategies using cyclodextrin complexes, solid dispersions, and solid self-emulsifying drug delivery systems is given. However, the major focus of this review is the application of nano-based approaches to the bioenhancement of curcumin. A description of the main advantages of nanosystems is followed by a detailed review of various nanosystems of curcumin, including nanosuspensions and various carrier-based nanosystems. Each nanosystem considered here is first briefly introduced, and then studies of the nanosystem containing curcumin are discussed. Lipid-based systems including liposomes and solid lipid nanoparticles, microemulsions, self-microemulsifying drug-delivery systems, nanoemulsions, and polymeric nanoparticles-which are widely explored-are dealt with in detail. Other miscellaneous systems discussed include inorganic nanoparticles, micelles, solid nanodispersions, phytosomes, and dendrimers. The possibility of using intact nanoparticles to achieve the targeted oral delivery of curcumin and thus harness the benefits of this wonder nutraceutical is an exciting prospect.