Apoptosis and bcl-2 expression in irradiated lungs and the effect of pentoxifylline.
We measured number of bcl-2, apoptotic, neutrophil, and surfactant apoprotein D (SP-D) positive cells in irradiated rat lungs during different time points after the sublethal whole-thorax irradiation of rats. We also investigated the influence of pentoxifylline (PTX) therapy on these markers. Wistar rats were given 15 Gy thoracic irradiation and PTX (35 mg/kg) twice a week. Animals were examined histologically and imunohistochemically at intervals from 1-12 weeks. In non-treated rats compared with treated rats, bcl-2 expression was significantly inhibited from 4 weeks after irradiation. A higher apoptosis presence in non-treated rats from 4 weeks was found and apoptosis development in PTX-treated animals was delayed and started 8 weeks after irradiation. Similar differences were measured during neutrophil granulocytes examination. Neutrophil penetration in non-treated rats was found 5 weeks after irradiation in contrast to the RP onset of PTX-treated animals 8 weeks after irradiation. The number of SP-D positive cells in non-treated rats observed until 5 weeks after irradiation was higher than in the control group. PTX-treated animals expressed higher number of SP-D positive cells during the whole experiment than the control group. We suggest that apoptosis is linked to neutrophil granulocyte actions during the RP onset and that PTX-therapy causes diminished inflammation development.
Osterreicher
J
J
Department of Radiobiology and Immunology, Purkynĕ Military Medical Academy, Hradec Králové. osterreicher@pmfhk.cz
Králik
M
M
Navrátil
L
L
Vávrová
J
J
Skopek
J
J
Knízek
J
J
Macela
A
A
D000818:Animals; D017209:Apoptosis / Q000528:radiation effects*; D006023:Glycoproteins / Q000378:metabolism; D007150:Immunohistochemistry; D008168:Lung / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D008297:Male; D009504:Neutrophils / Q000473:pathology; D010431:Pentoxifylline / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D037663:Pulmonary Surfactant-Associated Protein D; D011663:Pulmonary Surfactants / Q000378:metabolism; D017564:Radiation Pneumonitis / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D006023:Glycoproteins; D019253:Proto-Oncogene Proteins c-bcl-2; D037663:Pulmonary Surfactant-Associated Protein D; D011663:Pulmonary Surfactants; D011837:Radiation-Protective Agents; D010431:Pentoxifylline