7,8-Dihydroxyflavone-Functionalized Gold Nanoparticles Target The Arginase Enzyme of <i>Leishmania Donovani</i>
Pragya Prasanna, Prakash Kumar, Saptarshi Mandal, Tanvi Payal, Saurabh Kumar, Sk Ugir Hossain, Prolay Das, V. Ravichandiran, Debabrata Mandal
Abstract
Aim: To analyze the efficacy and possible mechanism of action of 7,8-dihydroxyflavone (DHF) and DHF synthesized gold nanoparticles (GNPs) against the parasite Leishmania donovani. Methods: GNPs were synthesized using DHF and characterized by dynamic light scattering, ζ potential, Fourier transform infrared spectroscopy, transmission electron microscopy and x-ray diffraction. The efficacy of DHF and DHF-GNP were tested against sensitive and drug-resistant parasites. GNP uptake was measured on macrophages by atomic absorption spectroscopy. Results: DHF and DHF-GNP (∼35 nm) were equally effective against sensitive and drug-resistant strains and inhibited the arginase activity of parasites. Increased IFN-γ and reduced IL-12 cytokine response showed a Th1/Th2-mediated cell death in macrophages. Conclusion: The low cytotoxicity and high biological activity of DHF-GNP may be useful for chemotherapy of leishmaniasis.