Γ-irradiation induced apoptosis in peritoneal macrophages by oxidative stress. implications of antioxidants in caspase mitochondrial pathway

• Published in: Anticancer research 2005-11, Vol.25 (6B), p.4091-4100
• Main Authors: HERNANDEZ-FLORES, Georgina, GOMEZ-CONTRERAS, Piedad C, DOMINGUEZ-RODRIGUEZ, Jorge R, LERMA-DIAZ, José Manuel, ORTIZ-LAZARENO, Pablo César, CERVANTES-MUNGUIA, Ramon, SAHAGUN-FLORES, José Ernesto, ORBACH-ARBOUYS, Simone, SCOTT-ALGARA, Daniel, BRAVO-CUELLAR, Alejandro
• Format: Article
• Language: English
• Subjects: Animals; Antioxidants - pharmacology; Apoptosis - physiology; Apoptosis - radiation effects; Biological and medical sciences; Caspase Inhibitors; Caspases - metabolism; Gamma Rays; Intracellular Membranes - physiology; Intracellular Membranes - radiation effects; Lipid Peroxides - blood; Macrophages, Peritoneal - cytology; Macrophages, Peritoneal - drug effects; Macrophages, Peritoneal - metabolism; Macrophages, Peritoneal - radiation effects; Male; Medical sciences; Membrane Potentials - physiology; Membrane Potentials - radiation effects; Mice; Mice, Inbred BALB C; Mitochondria - drug effects; Mitochondria - physiology; Mitochondria - radiation effects; Oxidative Stress - drug effects; Oxidative Stress - physiology; Oxidative Stress - radiation effects; Superoxide Dismutase - pharmacology; Tumors
• ISSN: 0250-7005; 1791-7530

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.