We synthesized 30 lipophilic bisphosphonates and tested them in malaria parasite killing (targeting parasite geranylgeranyl diphosphate synthase, GGPPS) and human gamma delta T cell activation (targeting human farnesyl diphosphate synthase, FPPS). Similar patterns of activity were seen in inhibiting human FPPS and Plasmodium GGPPS, with short to medium chain-length species having most activity. In cells, shorter chain-length species had low activity, due to poor membrane permeability, and longer chain length species were poor enzyme inhibitors. Optimal activity was thus seen with similar to C-10 side-chains, which have the best combination of enzyme inhibition and cell penetration. We also solved the crystal structure of one potent inhibitor, bound to FPPS. The results are of interest since they suggest the possibility of a combined chemo/immuno-therapeutic approach to antimalarial development in which both direct parasite killing and gamma delta T cell activation can be achieved with a single compound.
Cell Permeable Imidazole-Desferrioxamine Conjugates: Synthesis and In Vitro Evaluation
作者:Shreya Pramanik、Saikat Chakraborty、Malavika Sivan、Birija S. Patro、Sucheta Chatterjee、Dibakar Goswami
DOI:10.1021/acs.bioconjchem.8b00924
日期:2019.3.20
imidazolium cations with varied hydrophobicities have been conjugated with DFO. The iron binding abilities and the antioxidant properties of the conjugates were found to be similar to DFO. The degree of cellular internalization was much higher in the octyl-imidazolium-DFO conjugate (IV) compared with DFO, and IV was able to chelate LPI in vitro. This opens up a new avenue in using N-alkyl imidazolium