title: Anti-Acanthamoebic properties of resveratrol and demethoxycurcumin.
abstract: Acanthamoeba is an opportunist protist pathogen that is known to infect the cornea to produce eye keratitis and the central nervous system to produce fatal granulomatous encephalitis. Early diagnosis, followed by aggressive treatment using a combination of drugs is a prerequisite in successful treatment but even then, prognosis remains poor due to lack of effective drugs. The overall aim of the present study was to determine the anti-Acanthamoebic potential of natural compounds, resveratrol and curcuminoids. Adhesion and cytotoxicity assays were performed using primary human brain microvascular endothelial cells, which constitute the blood-brain barrier. Pre-exposure of organisms to 100 μg resveratrol and demethoxy curcumin prevented amoeba binding by 57% and 73%, respectively, while cytotoxicity of host cells was inhibited by 86%. In an assay for viability of amoebae in the absence of host cells, resveratrol and de-methoxy curcumin exhibited significant amoebicidal effects (23% and 25%, respectively) at 100 μg concentrations (P<0.01). Neither resveratrol nor demethoxycurcumin had any effect on the proteolytic activities of Acanthamoeba castellanii. Of both compounds, resveratrol is of most interest for further investigation, because of the selective toxicity of resveratrol on A. castellanii but not the human brain microvascular endothelial cells.
authors.affiliation: Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan.
authors.forename: Yousuf
authors.initials: Y
authors.lastname: Aqeel
authors.forename: Junaid
authors.initials: J
authors.lastname: Iqbal
authors.forename: Ruqaiyyah
authors.initials: R
authors.lastname: Siddiqui
authors.forename: Anwar H
authors.initials: AH
authors.lastname: Gilani
authors.forename: Naveed Ahmed
authors.initials: NA
authors.lastname: Khan
mesh_terms: D048248:Acanthamoeba castellanii / Q000187:drug effects* / Q000502:physiology; D001921:Brain / Q000098:blood supply / Q000166:cytology; D002448:Cell Adhesion / Q000187:drug effects; D016923:Cell Death / Q000187:drug effects; D002478:Cells, Cultured; D003474:Curcumin / Q000031:analogs & derivatives* / Q000494:pharmacology; D036381:Diarylheptanoids; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects; D006801:Humans; D055806:Microvessels / Q000166:cytology; D010447:Peptide Hydrolases / Q000187:drug effects; D000077185:Resveratrol; D013267:Stilbenes / Q000494:pharmacology*
chemical_list: D036381:Diarylheptanoids; D013267:Stilbenes; D010447:Peptide Hydrolases; D003474:Curcumin; D000077185:Resveratrol; C050229:demethoxycurcumin