Gamma-irradiation induced apoptosis in peritoneal macrophages by oxidative stress. Implications of antioxidants in caspase mitochondrial pathway.
The in vivo and in vitro development of apoptosis induced by gamma-irradiation was studied in mouse peritoneal macrophages. The apoptosis index was measured by fluorescence microscopy and DNA electrophoresis. In vivo apoptosis was greatest eight days after 8 Gy total body gamma-irradiation. A DNA ladder electrophoretic pattern was only observed in the gamma-irradiated group. The participation of reactive oxygen species in apoptosis induction was investigated by pretreating mice with the antioxidants superoxide dismutase, catalase, vitamin E or lipopolysaccharide before gamma-irradiation. Measurement of serum lipoperoxides showed oxidative stress in the gamma-irradiated mice and the protection given by the antioxidants. These results were confirmed using in vitro cultures of peritoneal macrophages: gamma-irradiated groups and antioxidant-pretreated gamma-irradiation groups showed results similar to those observed with in vivo irradiation. A loss of mitochondrial membrane potential (delta psi(m)) was also observed by microscopy in the gamma-irradiated cell cultures. Experiments with caspase inhibitors confirmed the participation of caspase 3 and caspase 9.
Hernández-Flores
Georgina
G
Centro de Investigación Biomédica de Occidente, IMSS, Guadalajara, Mexico.
Gómez-Contreras
Piedad C
PC
Domínguez-Rodríguez
Jorge R
JR
Lerma-Díaz
José Manuel
JM
Ortíz-Lazareno
Pablo César
PC
Cervantes-Munguía
Ramon
R
Sahagún-Flores
José Ernesto
JE
Orbach-Arbouys
Simone
S
Scott-Algara
Daniel
D
Bravo-Cuellar
Alejandro
A
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D017209:Apoptosis / Q000502:physiology / Q000528:radiation effects*; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism*; D005720:Gamma Rays; D007425:Intracellular Membranes / Q000502:physiology / Q000528:radiation effects; D008054:Lipid Peroxides / Q000097:blood; D017737:Macrophages, Peritoneal / Q000166:cytology / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects*; D008297:Male; D008564:Membrane Potentials / Q000502:physiology / Q000528:radiation effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008928:Mitochondria / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D013482:Superoxide Dismutase / Q000494:pharmacology
D000975:Antioxidants; D061945:Caspase Inhibitors; D008054:Lipid Peroxides; D013482:Superoxide Dismutase; D020169:Caspases