ATP converts necrosis to apoptosis in oxidant-injured endothelial cells

• Published in: Free radical biology & medicine Vol. 25; no. 6; pp. 694 - 702
• Main Authors: Lelli, Joseph L., Becks, Lauren L., Dabrowska, Milena I., Hinshaw, Daniel B.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.1998
• Subjects: Adenosine Triphosphate - metabolism; Adenosine Triphosphate - pharmacology; Animals; Apoptosis; Apoptosis - drug effects; ATP; Cattle; Cell Survival - drug effects; DNA Fragmentation - drug effects; Endothelial cells; Endothelium, Vascular - drug effects; Free radical; Glutamine; Glutamine - pharmacology; Hydrogen peroxide; Hydrogen Peroxide - pharmacology; Microscopy, Fluorescence; Necrosis; Oligomycins - pharmacology; Oxidative Stress - drug effects; Pulmonary Artery - pathology; Time Factors; Hydrogen peroxide; AO-EB; Gln; MGB; Endothelial cells; Free radical; Necrosis; H 2O 2; TCA; MI; ATP; Apoptosis; Glutamine
• ISSN: 0891-5849; 1873-4596
• DOI: 10.1016/S0891-5849(98)00107-5

Cell death due to necrosis results in acute inflammation, while death by apoptosis generally does not. The effect of adenosine triphosphate (ATP) on the pattern of cell death induced by oxidants was examined in bovine endothelial cells. ATP levels were altered by hydrogen peroxide (H 2O 2), glutamine (Gln), and metabolic inhibition (MI), to determine if necrosis can be shifted to apoptosis during oxidant injury. The form of cell death was determined by fluorescence microscopic techniques and the pattern of DNA degradation on agarose gels. ATP levels were measured using the luciferase–luciferin assay. Apoptosis occurred with 100 μM H 2O 2 without an alteration in ATP levels. ATP was significantly lowered with 5 mM H 2O 2, and necrosis occurred. MI, in combination with 100 μM H 2O 2, decreased ATP and resulted in necrosis. MI alone, however, did not cause cell death. Gln partially restored ATP levels in cells injured with 5 mM H 2O 2 and resulted in a significant increase in apoptosis. DNA laddering on agarose gels confirmed the apoptotic changes seen by fluorescence microscopy. In summary, a threshold level of ATP 25% of basal levels is required for apoptosis to proceed after oxidant stress, otherwise necrosis occurs. Agents like glutamine that enhance ATP levels in oxidant-stressed cells may be potent means of shifting cell death during inflammation to the noninflammatory form of death—apoptosis.