NADPH oxidase-mediated generation of reactive oxygen species is critically required for survival of undifferentiated human promyelocytic leukemia cell line HL-60.
Nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase) mediated generation of reactive oxygen species (ROS) was originally identified as the powerful host defense machinery against microorganism in phagocytes. But recent reports indicated that some non-phagocytic cells also have the NADPH oxidase activity, and the ROS produced by it may act as cell signal molecule. But as far as today, whether the NADPH oxidase also plays similar role in phagocyte has not been paid much attention. Utilizing the undifferentiated HL-60 promyelocytic leukemia cells as a model, the aim of the present study was to determine whether NADPH oxidase plays a role on ROS generation in undifferentiated HL-60, and the ROS mediated by it was essential for cell's survival. For the first time, we verified that the release of ROS in undifferentiated HL-60 was significantly increased by the stimulation with Calcium ionophore or opsonized zymosan, which are known to trigger respiration burst in phagocytes by NADPH oxidase pathway. Diphenylene iodonium (DPI) or apocynin (APO), two inhibitors of NADPH oxidase, significantly suppressed the increasing of ROS caused by opsonized zymosan. Cell survival assay and fluorescence double dyeing with acridine orange and ethidium bromide showed that DPI and APO, as well as superoxide dismutase (SOD) and catalase (CAT) concentration-dependently decreased the viability of undifferentiated HL-60 cells, whereas exogenous H2O2 can rescue the cells from death obviously. Our results suggested that the ROS, generated by NADPH oxidase play an essential role in the survival of undifferentiated HL-60 cells.
Dong
Jing-Mei
JM
Department of Physical, Lanzhou Teacher's College, Lanzhou, People's Republic of China.
Zhao
Sheng-Guo
SG
Huang
Guo-Yin
GY
Liu
Qing
Q
D000098:Acetophenones / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D018922:HL-60 Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D007476:Ionophores / Q000494:pharmacology; D015473:Leukemia, Promyelocytic, Acute / Q000188:drug therapy / Q000378:metabolism*; D019255:NADPH Oxidases / Q000378:metabolism*; D009861:Onium Compounds / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013997:Time Factors; D015054:Zymosan / Q000494:pharmacology
D000098:Acetophenones; D007476:Ionophores; D009861:Onium Compounds; D017382:Reactive Oxygen Species; C007517:diphenyleneiodonium; D015054:Zymosan; C056165:acetovanillone; D006861:Hydrogen Peroxide; D019255:NADPH Oxidases