Radioprotective effect of cyclo(L-phenylalanyl-L-prolyl) on irradiated rat lung.
In the present study, we investigated the radioprotective effect of cyclo(L-phenylalanyl-L-prolyl) on irradiated rat lungs to determine its potential as a radioprotective agent. We found that early lung damage induced by irradiation was reduced by treatment with 40 mg/kg of cyclo(Lphenylalanyl- L-prolyl) in the latent and early pneumonitis phases. Expression of TNF-alpha and TGF-beta1 at 2 and TGF-beta1 at 8 weeks post-irradiation was decreased in animals that received both radiation and cyclo(L-phenylalanyl-L-prolyl) compared with animals that received radiation alone. Evidence indicated that the proinflammatory cytokine TNF-alpha and the fibrogenic cytokine TGF-beta1 likely play a role in the radioprotective effect of cyclo(L-phenylalanyl-L-prolyl). However, besides TNF-alpha and TGF-beta1 expressions, the precise mechanism by which cyclo(L-phenylalanyl-L-prolyl) ameliorates the induced radiation damage is not clear.
Lee
Keyong Ho
KH
College of Industrial Sciences, Kongju National University, Yesan 340-802, Korea.
Rhee
Ki Hyeong
KH
D000818:Animals; D002460:Cell Line; D016207:Cytokines / Q000378:metabolism / Q000528:radiation effects; D004151:Dipeptides / Q000494:pharmacology* / Q000627:therapeutic use; D016166:Free Radical Scavengers / Q000494:pharmacology / Q000627:therapeutic use; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D008297:Male; D010456:Peptides, Cyclic / Q000494:pharmacology* / Q000627:therapeutic use; D011833:Radiation Injuries, Experimental / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D011837:Radiation-Protective Agents / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley
D016207:Cytokines; D004151:Dipeptides; D016166:Free Radical Scavengers; D010456:Peptides, Cyclic; D011837:Radiation-Protective Agents; C118540:cyclo(phenylalanyl-prolyl)