Assessment of antimalarial activity and proteomics analysis of Dioscorea membranacea Pierre.

Multidrug resistance Plasmodium falciparum remains a significant global health problem worldwide. New alternative antimalarial drugs are urgently needed. Dioscorea membranacea Pierre. is a Thai-medicinal plant that has been shown to exhibit a wide range of pharmacological activities. The study aimed to investigate antimalarial activity and possible protein targets of action of the crude ethanolic extract of the rhizome of this plant.  The in vitro antimalarial activity expressed as IC50 (concentration that inhibits the parasite growth by 50%) of the extract against 3D7 chloroquine-sensitive P. falciparum and K1 chloroquine-resistant P. falciparum clones were 10.1 (8.8-10.3) and 9.3 (9.17-9.63) µg/ml [median (range)], respectively. The cytotoxicity of against the human fibroblast cell OUMS-36T-1F was 96.4 (96.3-96.5) µg/ml.  The selectivity index (SI) for the 3D7 and K1 clones was 9.5 and 10.4, respectively. Preliminary investigation of the protein targets of action in 3D7 P. falciparum clone revealed 13 up-regulated protein spots and 14 down-regulated protein spots. For further development of D. membranacea Pierre. as a promising antimalarial drug candidate, identification of these proteins by mass spectrometry and investigation of their mode of antimalarial actions are encouraged.   Key words: Malaria, proteomics, Dioscorea membranacea Pierre.