Induction of apoptosis and reactive oxygen species production by N-nitrosopiperidine and N-nitrosodibutylamine in human leukemia cells.

Abstract

N-nitrosopiperidine (NPIP) and N-nitrosodibutylamine (NDBA) belong to a group of N-nitrosamines that are widely distributed in foodstuffs and the occupational environment. In the present study, the human promyelocytic leukemia cell line HL-60, was used to characterize the apoptotic effects of N-nitrosamines, and to examine the production of reactive oxygen species (ROS). Apoptotic cells were identified by (i) chromatin condensation (ii) flow cytometry analysis and (iii) poly(ADP-ribose) polymerase (PARP) cleavage. NPIP and NDBA induced morphological changes consistent with apoptotic events in HL-60 cells. Flow cytometry analysis showed that both N-nitrosamines induced apoptotic cell death in a concentration and time dependent-manner. It was observed that NDBA was stronger than NPIP, since it induced a significant apoptotic cell death after 18 h starting from a concentration of 2 mm, whereas NPIP was effective at 10 mm. Furthermore, PARP was markedly cleaved with 0.5 mm of NDBA and 5 mm of NPIP after treatments for 3 and 18 h, respectively. Finally, the ROS level was found to be elevated after 0.5 h of treatment with both N-nitrosamines. Antioxidant N-acetylcysteine (NAC) completely inhibited the ROS production induced by NPIP and NDBA. However, this action seems not to be associated with the apoptosis because NAC did not block N-nitrosamines-induced apoptosis. The data demonstrate that NPIP and NDBA induce apoptosis and ROS production in HL-60 cells.

• Authors: Almudena García, Paloma Morales, Nuria Arranz, Eugenia Delgado, Joseph Rafter, Ana I Haza
• Journal: Journal of applied toxicology : JAT (J Appl Toxicol) Vol. 28 Issue 4 Pg. 455-65 (May 2008) ISSN: 0260-437X [Print] England
• PMID: 17929238 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright (c) 2007 John Wiley & Sons, Ltd.

Chemical References

• Antioxidants
• Carcinogens
• Nitrosamines
• Reactive Oxygen Species
• N-nitrosopiperidine
• dibutylnitrosamine
• Poly(ADP-ribose) Polymerases
• Acetylcysteine

Topics

• Acetylcysteine (pharmacology)
• Antioxidants (pharmacology)
• Apoptosis (drug effects)
• Blotting, Western
• Carcinogens (toxicity)
• Cell Shape (drug effects)
• Cell Survival (drug effects)
• Chromatin Assembly and Disassembly (drug effects)
• Dose-Response Relationship, Drug
• Flow Cytometry
• HL-60 Cells
• Humans
• In Situ Nick-End Labeling
• Leukemia (metabolism, pathology)
• Nitrosamines (toxicity)
• Oxidative Stress (drug effects)
• Poly(ADP-ribose) Polymerases (metabolism)
• Reactive Oxygen Species (metabolism)
• Time Factors