Hyperbaric oxygen enhances apoptosis in hematopoietic cells.

TitleHyperbaric oxygen enhances apoptosis in hematopoietic cells.
Publication TypeJournal Article
Year of Publication2002
AuthorsGanguly BJ, Tonomura N, Benson RM, Osborne BA, Granowitz EV
JournalApoptosis : an international journal on programmed cell death
Date Published2002 Dec
AbstractHyperbaric oxygen (HBO) is 100% oxygen administered at elevated atmospheric pressure. In this study, we examined the effect of HBO on hematopoietic cell apoptosis. Cells exposed to HBO were incubated in a chamber containing 97.9% O(2) and 2.1% CO(2) at 2.4 atmospheres absolute (ATA). HBO enhanced spontaneous HL-60 cell apoptosis in a time-dependent manner; a 12 h exposure increased apoptosis by 42%. Exposing these cells to hyperoxia at standard atmospheric pressure (95% O(2), 5% CO(2) at 1 ATA) or increased pressure alone (8.75% O(2), 2.1% CO(2) at 2.4 ATA) had minimal effect on apoptosis. HBO also enhanced stimulus-induced apoptosis. HL-60 cells stimulated to die using gamma radiation underwent 33% more apoptosis than cells exposed to radiation alone. HBO enhanced melphalan, camptothecin, and chlorambucil-induced apoptosis by 22%, 13%, and 8%, respectively. Jurkat cells stimulated to die with anti-Fas antibody underwent 44% more apoptosis when exposed to HBO. Spontaneous apoptosis was increased by 15% in HBO-exposed murine thymocytes. HBO’s effect on apoptosis did not require new protein synthesis. As expected, HBO exposure increased the intracellular concentration of H(2)O(2). Incubating HL-60 cells in the presence of dehydroascorbic acid partially abrogated HBO-induced increases in intracellular H(2)O(2) and apoptosis. In summary, HBO enhances spontaneous and stimulus-induced apoptosis in hematopoietic cells, at least in part, by enhancing the intracellular accumulation of H(2)O(2).
Alternate JournalApoptosis