Enteral administration of proteinase mixture inhibits development of radiation pneumonitis and lung fibrosis in rats
Österreicher J.,1 ?kopek J.,2 Navrátil L.,2 Kní?ek J.,1 ?ebková V.,3 Macela A.1
1) Purkyn? Military Medical Academy, Hradec Králove, Czech Republic
2) Department of Biophysics, 1st Medical School of Charles University, Prague, Czech Republic
3) Department of Immunology, St. Elisabeth Hospital, Prague, Czech Republic
Inter Journal of. Immunotherapy 2000, Vol. XVI, No.3/4, pp. 45-51
507 KA (4-12-3) (19-06-2)
Summary: Wistar rats underwent a sublethal whole-thorax irradiation. One group of animals received a mix ture of proteinases (60 mg/kg/day) by rectum every 12 h from day 1 following irradiation to the end of the experiment. Saline-treated animals were used as a control. The animals were observed for 8 and 42 weeks following irradiation. Transforming growth factor- b(TGF- b) 1-, 2- and 3-positive cells, alveolar septal thickness, neutrophil granulocyte number and connective tissue content in the lung tissue of the rats were measured. During the onset of the inflammatory phase, a significantly lower neutrophil number was found in the enzyme-treated rats in comparison to the saline-treated control animals. Furthermore, mixture of proteinases inhibit ed TGF- b 1 and 2 expression. During the onset of the fibrotic phase, significantly lower alveolar septal thick ness, TGF- b 2 and 3 expression and connective tissue content were found in the group of enzyme-treated rats as compared to control rats. Based on the obtained results we suggest that specific mixtures of pro teinases show both antiinflammatory and antifibrotic effects.