title: Antiproliferative activity of the isofuranonaphthoquinone isolated from Bulbine frutescens against Jurkat T cells.
abstract: Cancer is a major public health burden in both developed and developing countries. The quinone moiety has been shown to possess antitumor activity and several cancer drugs in clinical use contain this entity. The effect of isofuranonaphthoquinone isolated from Bulbine frutescens on Jurkat T cells was determined. Cells were exposed to the isofuranonaphthoquinone (IFNQ) at different concentrations. Significant antiproliferative effects were observed which were comparable to that of the anticancer drug 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). A combination of IFNQ with BCNU produced synergistic effects which were observed after 72 hrs. It was also observed that combining IFNQ with reduced glutathione abolished the anticancer activity of the compound. It is, therefore, proposed that the isofuranonaphthoquinone may exert part of its effect by producing reactive oxygen species resulting in death of the cells as the effects of this compound were antagonized by reduced glutathione. An investigation on the effects of isofuranonaphthoquinone on glutathione transferase (GST) activity and drug efflux pumps showed that this compound exhibited inhibitory effects on both the GST and the drug efflux pumping activities. Thus, the isofuranonaphthoquinone showed cytotoxicity, works through inhibition of some cellular mechanisms, and could present a potential source of lead compounds for anticancer drug development.
authors.affiliation: School of Pharmacy, College of Health Sciences, University of Zimbabwe, Mount Pleasant, Harare, Zimbabwe.
authors.forename: Penelope
authors.initials: P
authors.lastname: Tambama
authors.affiliation: The African Academy of Sciences, P.O. Box 24916, Nairobi, Kenya.
authors.forename: Berhanu
authors.initials: B
authors.lastname: Abegaz
authors.affiliation: Biomolecular Interactions Analyses Group, Department of Biochemistry, University of Zimbabwe, P.O. Box MP 167, Mount Pleasant, Harare, Zimbabwe.
authors.forename: Stanley
authors.identifier: 0000-0001-6071-6439
authors.initials: S
authors.lastname: Mukanganyama
mesh_terms: D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D019169:Jurkat Cells; D019668:Liliaceae / Q000737:chemistry; D009285:Naphthoquinones / Q000008:administration & dosage*; D009369:Neoplasms / Q000188:drug therapy* / Q000473:pathology; D010936:Plant Extracts / Q000008:administration & dosage* / Q000737:chemistry
chemical_list: D009285:Naphthoquinones; D010936:Plant Extracts