Identification and screening of antimalarial phytochemical reservoir from northeastern Indian plants to develop PfRIO-2 kinase inhibitor

摘要

Every year, malaria caused by Plasmodium falciparum leads to 1 million deaths. Disease condition is alarming due to acquired resistance in parasite against antimalarial drugs in circulation. It brings the necessity to design novel inhibitors against newly identified drug targets. RIO-2 kinase regulates ribosome biogenesis and represents a promising drug target. Northeastern region of India is a biodiversity hub with a rich source of medicinal plants. Medicinal plants represent a source of phytochemical library to be screened to develop an inhibitor against the PfRIO-2 kinase. In current report, we selected plants with known antimalarial activity and performed in silico screening with phytochemicals against PfRIO-2 as a target. The majority of antimalarial phytochemicals docked very well into the ATP binding pocket of the PfRIO-2 kinase. A competition assay with substrate ATP indicates that a total of 5 phytochemicals, rutin, bebeerines, isochondrodendrine, nimbin and punicalagin, share similar interactions with protein residues within the ATP binding pocket and have potential to inhibit ATP binding. A significant relationship was found between docking energy and experimentally determined antimalarial values of rutin, bebeerines, isochondrodendrine, nimbin and punicalagin (R 2 = 0.91, p 0.001). Docking and virtual screening has identified lead phytochemicals, namely rutin, bebeerines, isochondrodendrine, nimbin and punicalagin, as a potent PfRIO-2 inhibitor, but cannot replace experimental verification. We are hopeful that the current study will help to understand the antimalarial action of the phytochemicals and design effective chemotherapy against malaria.