In vivo adriamycin-induced apoptosis in peritoneal murine macrophages: partial participation of a caspase cascade.
BACKGROUND
Adriamycin (ADM) is a potent antitumor drug that induces apoptosis (AP) in tumor cells. AP is modulated by caspases and by mitogen-activated protein kinases (MAPK) as well as by the mitochondrial membrane potential (deltapsim). We studied the participation of these systems in peritoneal macrophages from ADM-treated mice.


METHODS
Balb/c mice were either treated with ADM (5 mg/kg, i.p.) or with 0.85% NaCl solution (controls). One hour later, peritoneal cells were harvested and cultured for 28 h. AP was evaluated by ethidium bromide and acridine orange staining; deltapsim was monitored using a MitoCapture stain Kit; DNA integrity was assessed by electrophoretic analysis. Animals were treated (i.p.) 1 h before ADM administration with Z-LEHD-FMK, Z-DEVD-FMK, or Z-VAD-FMK (caspase-9, caspases-3, 7,10 and general caspase inhibitors, respectively) or with PD169316 (a MAPKp38 inhibitor).


RESULTS
ADM induced a higher rate of AP and the characteristic electrophoretic DNA ladder pattern. Mice treated with caspases inhibitors plus ADM showed significant reductions in AP and DNA laddering; in contrast, no differences were observed in mice treated with PD169316 plus ADM in comparison with ADM alone. ADM also induced early loss of the deltapsim.


CONCLUSIONS
In these experimental conditions, ADM induced AP in a mainly caspase-9-dependent manner and this was related to a reduction in the deltapsim.
Domínguez-Rodríguez
Jorge R
JR
Centro de Investigación Biomédica de Occidente del IMSS, Universidad de Guadalajara, Jalisco, México.
Chaparro-Huerta
Veronica
V
Hernández-Flores
Georgina
G
Gómez-Contreras
Piedad C
PC
Lerma-Dáz
José M
JM
Ortiz-Lazareno
Pablo C
PC
Cervantes-Munguia
Ramón
R
Orbach-Arbouys
Simone
S
Scott-Algara
Daniel
D
Cuellar
Alejandro Bravo
AB
D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D053453:Caspase 9; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism*; D004317:Doxorubicin / Q000494:pharmacology*; D007425:Intracellular Membranes / Q000187:drug effects / Q000502:physiology; D017737:Macrophages, Peritoneal / Q000166:cytology* / Q000187:drug effects* / Q000201:enzymology; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008928:Mitochondria / Q000187:drug effects / Q000502:physiology; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
D000903:Antibiotics, Antineoplastic; D061945:Caspase Inhibitors; D004317:Doxorubicin; D048051:p38 Mitogen-Activated Protein Kinases; C506434:Casp9 protein, mouse; D053453:Caspase 9; D020169:Caspases