Manganese induces apoptosis of human B cells: caspase-dependent cell death blocked by Bcl-2
| Autor: | Nicolas Schrantz, Marie-Thérèse Auffredou, Aimé Vazquez, Gérald Leca, Françoise Mitenne, Dominique Blanchard |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Programmed cell death
Poly ADP ribose polymerase Apoptosis Caspase 3 Cysteine Proteinase Inhibitors Amino Acid Chloromethyl Ketones Cell Line Tumor Cells Cultured medicine Humans Molecular Biology Caspase B cell Cell Line Transformed Inhibitor of apoptosis domain B-Lymphocytes Manganese Cell Death biology Cell growth Caspase 1 Cell Biology Molecular biology Cell biology Enzyme Activation medicine.anatomical_structure Proto-Oncogene Proteins c-bcl-2 Caspases biology.protein Poly(ADP-ribose) Polymerases |
| Zdroj: | Cell Death & Differentiation. 6:445-453 |
| ISSN: | 1476-5403 1350-9047 |
| DOI: | 10.1038/sj.cdd.4400508 |
| Popis: | Manganese ions block apoptosis of phagocytes induced by various agents. The prevention of apoptosis was attributed to the activation of manganous superoxide dismutase (Mn-SOD) and to the antioxidant function of free Mn2+ cations. However, the effect of Mn2+ on B cell apoptosis is not documented. In this study, we investigated the effects of Mn2+ on the apoptotic process in human B cells. We observed that Mn2+ but not Mg2+ or Ca2+, inhibited cell growth and induced apoptosis of activated tonsilar B cells, Epstein Barr virus (EBV)-negative Burkitt's lymphoma cell lines (BL-CL) and EBV-transformed B cell lines (EBV-BCL). In the same conditions, no apoptosis was observed in U937, a monoblastic cell line. Induction of B cell apoptosis by Mn2+ was time- and dose-dependent. The cell permeable tripeptide inhibitor of ICE family cysteine proteases, zVAD-fmk, suppressed Mn2+-induced apoptosis. Furthermore, Mn2+ triggered the activation of interleukin-1beta converting enzyme (ICE/caspase 1), followed by the activation of CPP32/Yama/Apopain/caspase-3. In addition, poly-(ADP-ribose) polymerase (PARP), a cellular substrate for CPP32 protease was degraded to generate apoptotic fragments in Mn2+-treated B cell lines. The inhibitor, zVAD-fmk suppressed Mn2+-triggered CPP32 activation and PARP cleavage and apoptosis. These results indicate that the activation of caspase family proteases is required for the apoptotic process induced by Mn2+ treatment of B cells. While the caspase-1 inhibitor YVAD was unable to block apoptosis, the caspase-3 specific inhibitor DEVD-cmk, partially inhibited Mn2+-induced CPP32 activation, PARP cleavage and apoptosis of cells. Moreover, Bcl-2 overexpression in BL-CL effectively protected cells from apoptosis and cell death induced by manganese. This is the first report showing the involvement of Mn2+ in the regulation of B lymphocyte death presumably via a caspase-dependent process with a death-protective effect of Bcl-2. |
| Databáze: | OpenAIRE |
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