title: Anti-inflammatory and anticholinesterase activity of six flavonoids isolated from Polygonum and Dorstenia species.
abstract: This study was aimed at investigating the anti-inflammatory and anticholinesterase activity of six naturally occurring flavonoids: (-) pinostrobin (1), 2',4'-dihydroxy-3',6'-dimethoxychalcone (2), 6-8-diprenyleriodictyol (3), isobavachalcone (4), 4-hydroxylonchocarpin (5) and 6-prenylapigenin (6). These compounds were isolated from Dorstenia and Polygonum species used traditionally to treat pain. The anti-inflammatory activity was determined by using the Griess assay and the 15-lipoxygenase inhibitory activity was determined with the ferrous oxidation-xylenol orange assay. Acetylcholinesterase inhibition was determined by the Ellman's method. At the lowest concentration tested (3.12 µg/ml), compounds 2, 3 and 4 had significant NO inhibitory activity with 90.71, 84.65 and 79.57 % inhibition respectively compared to the positive control quercetin (67.93 %). At this concentration there was no significant cytotoxicity against macrophages with 91.67, 72.86 and 70.86 % cell viability respectively, compared to 73.1 % for quercetin. Compound 4 had the most potent lipoxygenase inhibitory activity (IC50of 25.92 µg/ml). With the exception of (-) pinostrobin (1), all the flavonoids had selective anticholinesterase activity with IC50values ranging between 5.93 and 8.76 µg/ml compared to the IC504.94 µg/ml of eserine the positive control. These results indicate that the studied flavonoids especially isobavachalcone are potential anti-inflammatory natural products that may have the potential to be developed as therapeutic agents against inflammatory conditions and even Alzheimer's disease.
authors.affiliation: Phytomedicine Programme, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria, 0110, South Africa. jpdzoyem@yahoo.fr.|Department of Biochemistry, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon. jpdzoyem@yahoo.fr.
authors.forename: Jean Paul
authors.initials: JP
authors.lastname: Dzoyem
authors.affiliation: Department of Organic Chemistry, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon.
authors.forename: Antoine H L
authors.initials: AHL
authors.lastname: Nkuete
authors.affiliation: Faculty of Medicine and Biomedical Sciences, University of Yaounde I, P.O. Box 1364, Dschang, Cameroon.
authors.forename: Barthelemy
authors.initials: B
authors.lastname: Ngameni
authors.affiliation: Phytomedicine Programme, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria, 0110, South Africa. kobus.eloff@up.ac.za.
authors.forename: Jacobus N
authors.initials: JN
authors.lastname: Eloff
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000302:isolation & purification / Q000494:pharmacology*; D002163:Cameroon; D018929:Cell Culture Techniques; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002800:Cholinesterase Inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000302:isolation & purification / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D016488:Medicine, African Traditional; D051379:Mice; D015394:Molecular Structure; D029586:Moraceae / Q000737:chemistry* / Q000254:growth & development; D009569:Nitric Oxide / Q000096:biosynthesis; D028502:Polygonum / Q000737:chemistry* / Q000254:growth & development
chemical_list: D000893:Anti-Inflammatory Agents; D002800:Cholinesterase Inhibitors; D005419:Flavonoids; D009569:Nitric Oxide
keywords: 15-Lipoxygenase; Anticholinesterase; Flavonoids; Nitric oxide production inhibition