BENGALURU: A group of researchers has devised a method to crush curcumin, a substance in turmeric, into tiny particles of 20 to 50 nanometre in diametre, which can be delivered orally as a form of antimalarial therapy. A strand of human hair has a diametre of about 60,000 nanometre.
Avadhesha Surolia, a professor at the Molecular Biophysics Unit at Indian Institute of Science (IISc), Aparajita Ghosh and Suman Bhandary at the division of Molecular Medicine at Bose Institute in Kolkata, and Tanushree Banerjee from the Department of Biotechnology at the University of Pune have worked on developing this method.
However, curcumin does not dissolve completely in water and therefore is not absorbed by cells, a phenomenon known as low bioavailability.
Curcumin has been shown to have anti-parasite effects on infectious agents such as Leishmania, Trypanosoma, Giardia and malaria-causing Plasmodium falciparum. Malaria parasites live in red blood cells after infection.
Nanoparticle-based malaria therapy has been explored before as it has the advantage of improving the interaction with infected red blood cells. However, there have been issues with safety and biocompatibility.
The nanotised curcumin developed in this study has been shown to effectively treat malaria-infested mice. In experiments conducted on mice infected with Plasmodium berghei, a relative of malaria-causing Plasmodium falciparum and P. vivax, mice treated with nanotised curcumin survived for 34 days and the parasites were cleared from their blood. Mice treated with native curcumin could only survive for 22 days.
When treatment was continued with nanotised curcumin, mice survived for more than two months, and almost 50 per cent of them were completely cured. The onset of pathological symptoms like ataxia, convulsions, and hypothermia was much delayed when nanotised curcumin was used. These nanotised curcumin particles are also independent of a “carrier” The procedure allows it to disperse in water, while natural curcumin is only soluble in organic solvents.
This increased the bioavailability of nanotised curcumin, compared to that of native curcumin. The dried curcumin can also be stored for a year.
Release of curcumin also occurred in a controlled manner, with 50 per cent of the drug released by 24 hours and curcumin still retained after 48 hours. It was also highly effective - it could wipe out parasites at one-tenth the concentration of native curcumin.
Nanotised curcumin, delivered orally in this study, has striking therapeutic potential.