title: Antimalarial activity of nepodin isolated from Rumex crispus.
abstract: The purpose of this study is to define the antimalarial activity of Rumex crispus. To identify an active compound that is isolated from R. crispus, bioassay-based chromatographic fractionation and purification is carried out from 70 % ethanol extract of R. crispus; then, an active compound, nepodin, is identified by spectroscopic analysis. Anitmalarial activity is measured by PfNDH2 assay, cytotoxicity, and animal test. From NADH:quinone oxidoreductase enzyme (PfNDAH2) assay, nepodin exhibited significant IC50 values that were 0.74 ± 0.07 and 0.79 ± 0.06 μg/ml against P. falciparum chloroquine-sensitive (3D7) and P. falciparum chloroquine-resistant (S20), respectively. Nepodin showed a potential selective inhibition (SI index: ratio of 50 % cytotoxic concentration to 50 % effective anti-plasmodial concentration) of 161.6 and 151.4 against P. falciparum 3D7 and P. falciparum S20. In the animal test, all groups of nepodin treatment of 10, 50, and 250 mg/kg were active with a parasitemia suppression of 97.1 ± 3.3, 99.1 ± 3.7, and 99.1 ± 2.6 %, respectively. The survival time with nepodin treatment was increased by 14.6 ± 2.5, 16.2 ± 1.5, and 19.8 ± 1.7 days at each dose, respectively. This study newly identified the plant R. crispus containing nepodin, which is a potential antimalarial compound. It exhibited the inhibitory activity of PfNDH2 and prolonged the survival time on the group of nepodin treatment; moreover, it inhibited the parasitemia in the animal test.
authors: Chong Kun Dang Research Institute, CKD Pharmaceuticals Inc., Yongin, 446-916, South Korea.
authors: Keyong Ho
authors: KH
authors: Lee
authors: Ki-Hyeong
authors: KH
authors: Rhee
mesh_terms: D000818:Animals; D000962:Antimalarials / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D005591:Chemical Fractionation; D002522:Chlorocebus aethiops; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology / Q000633:toxicity; D016778:Malaria, Falciparum / Q000188:drug therapy* / Q000469:parasitology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009281:Naphthalenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity; D010946:Plants, Medicinal; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000254:growth & development; D011808:Quinone Reductases / Q000037:antagonists & inhibitors / Q000378:metabolism; D031804:Rumex / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013997:Time Factors; D014709:Vero Cells
chemical_list: D000962:Antimalarials; D004791:Enzyme Inhibitors; D009281:Naphthalenes; D010936:Plant Extracts; D012997:Solvents; C041831:NADH dehydrogenase (quinone); D011808:Quinone Reductases; C583965:nepodin