title: Toxicity mechanisms of onion (Allium cepa) extracts and compounds in multidrug resistant erythroleukemic cell line.
abstract: Onion (Allium cepa) is being studied as a potential anticancer agent, but little is known regarding its effect in multidrug resistance (MDR) cells. In this work, the cytotoxicity of crude onion extract (OE) and fractioned extract (aqueous, methanolic and ethyl acetate), as well as some onion compounds (quercetin and propyl disulfide) were evaluated in Lucena MDR human erythroleukemic and its K562 parental cell line. The capacity of OE to induce apoptosis and/or necrosis in these cells, the possible participation of oxidative stress and DNA damage were also assessed. Similar sensitivities were obtained for both tumoral cells, however only OE caused significant effects in the cells. In K562 cells, a significant increase of apoptosis was verified while the Lucena cells experienced a significant increase of necrosis. An antioxidant capacity was verified for OE discarding oxidative damage. However, OE provoked similar significant DNA damage in both cell lines. Thus, the OE capacity to overcome the MDR phenotype suggests anti-MDR action of OE.
authors.affiliation: Laboratorio de Cultura Celular, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, Brazil.
authors.forename: Ana P S
authors.initials: AP
authors.lastname: Votto
authors.forename: Beatriz S
authors.initials: BS
authors.lastname: Domingues
authors.forename: Michele M
authors.initials: MM
authors.lastname: de Souza
authors.forename: Flavio M R
authors.initials: FM
authors.lastname: da Silva Júnior
authors.forename: Sergiane S
authors.initials: SS
authors.lastname: Caldas
authors.forename: Daza M V B
authors.initials: DM
authors.lastname: Filgueira
authors.forename: Rosilene M
authors.initials: RM
authors.lastname: Clementin
authors.forename: Ednei G
authors.initials: EG
authors.lastname: Primel
authors.forename: Adriana L
authors.initials: AL
authors.lastname: Vallochi
authors.forename: Eliana B
authors.initials: EB
authors.lastname: Furlong
authors.forename: Gilma S
authors.initials: GS
authors.lastname: Trindade
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis; D004249:DNA Damage; D004220:Disulfides / Q000032:analysis / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D006801:Humans; D020014:K562 Cells / Q000187:drug effects; D007928:Lethal Dose 50; D009336:Necrosis; D019697:Onions / Q000737:chemistry*; D010641:Phenotype; D010936:Plant Extracts / Q000494:pharmacology*; D011794:Quercetin / Q000032:analysis / Q000494:pharmacology; D013997:Time Factors
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004220:Disulfides; D010936:Plant Extracts; D011794:Quercetin