Current developments in Nano/Micro-formulations for enhanced delivery and bioactivity of andrographolide

Abstract

Andrographolide (Andro) is a major diterpene compound obtained from Andrographis paniculata and it is a well-established bioactive compound that has potential to treat many disorders that require inhibition of multiple signaling pathways. The structural characteristics of andro was changed by adding functional groups or chemically modified to obtain many of derivatives and there are certain derivative compounds which possess specific bioactivity much better than andro itself. Apart from the synthetic derivatives there are many natural analogues that are biologically active. Hence, it is apt to say Andrographis paniculata is a well explored plant species with multiple biological activity. However, some of the major concerns with andro is its poor solubility both in water and lipids that makes the bioavailability of andro considerably lower and it has poor stability in the alkaline environment. Further, it undergoes rapid first pass mechanism, converted into less effective sulphated metabolite and also rapidly eliminated through ileum with the help of efflux transporters. Drug delivery systems are highly sorted chemical entities for improvement of poorly bioavailable drug and andro has showed promising pharmacokinetic and pharmacodynamic properties with different drug delivery systems likes, polymers, gels, emulsion, nano/micro particle systems, liposomes, lipid nanoparticles and etc. The bioavailability of andro was observed to be best with polymeric delivery systems with enhanced specific bioactivity. This review is focused in various bioactivities of andrographolide and ability of various drug delivery systems to improve its efficacy by increasing the bioavailability.