title: NOX1 participates in ROS-dependent cell death of colon epithelial Caco2 cells induced by Entamoeba histolytica.
abstract: Entamoeba histolytica, which causes amebic colitis and occasional liver abscesses in humans, can induce host cell death through apoptosis and necrosis. Recently, we have demonstrated that E. histolytica can induce cell death in neutrophils via diphenyleneiodonium-sensitive NADPH oxidase (NOX)-derived reactive oxygen species (ROS). Although there are enzyme systems similar to the phagocyte NADPH oxidase system in many non-phagocytic cell types, the signaling role of NOX-derived ROS in cell death of human colon epithelial cells induced by E. histolytica remains obscure. Incubation of colon epithelial Caco2 tumor cell lines with amebic trophozoites resulted in intracellular ROS generation and cell death in a caspase-independent manner. Pretreatment with DPI, an inhibitor of NOX, strongly decreased E. histolytica-induced cell death in Caco2 cells. As identified by RT-PCR, NOX1 transcripts were highly expressed in Caco2 cells. siRNA-mediated suppression of NOX1 protein significantly inhibited E. histolytica-induced cell death and ROS response in Caco2 cells. These results suggest that NOX1 participates in the ROS-dependent cell death of colon epithelial cells induced by amebic adhesion during the early phase of intestinal amebiasis.
authors: Department of Environmental Medical Biology, Yonsei University College of Medicine, 134 Sinchon dong, Seodaemun gu, Seoul 120-752, Republic of Korea.
authors: Kyeong Ah
authors: KA
authors: Kim
authors: Ju Young
authors: JY
authors: Kim
authors: Young Ah
authors: YA
authors: Lee
authors: Kyoung-Ju
authors: KJ
authors: Song
authors: Deulle
authors: D
authors: Min
authors: Myeong Heon
authors: MH
authors: Shin
mesh_terms: D000818:Animals; D018938:Caco-2 Cells; D016923:Cell Death; D004748:Entamoeba histolytica / Q000166:cytology / Q000502:physiology*; D004749:Entamoebiasis / Q000382:microbiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006801:Humans; D000074624:NADPH Oxidase 1; D019255:NADPH Oxidases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D009861:Onium Compounds / Q000494:pharmacology*; D034741:RNA, Small Interfering / Q000502:physiology; D011817:Rabbits; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D004791:Enzyme Inhibitors; D009861:Onium Compounds; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; C007517:diphenyleneiodonium; D000074624:NADPH Oxidase 1; D019255:NADPH Oxidases; C402799:NOX1 protein, human