The Role of Oxidative Radicals in Radiation Pneumonitis and defensive effects of anti-oxidant agents

1996 Fiscal Year Final Research Report Summary

• Project/Area Number: 07671000
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Radiation science
• Research Institution: Kobe Univ.School of Med.Dept.of Rad.
• Principal Investigator: KODAMA Akihisa Kobe Univ.School of Med.Dept.of Rad., 医学部, 助手 (30252787)
• Co-Investigator(Kenkyū-buntansha): IZUMIYAMA Kazutaka Kobe Univ.School of Med.Dept.of Rad., 医学部附属病院, 助手 (60212958) ; KONO Michio Kobe Univ.School of Med.Dept.of Rad., 医学部, 教授 (60030938) ; KODAMA Akihisa Kobe Univ.School of Med.Dept.of Rad.
• Project Period (FY): 1995 – 1996
• Keywords: radiation pneumonitis / lipid peroxidation / gas chromatography / mass spectrometory (GC / MS) / free radical

Research Abstract

Radiation pneuminitis (RP) is thought to be caused by free radicals such as oxidative radical pruduced by irradiation. It is assumed that free radicals mainly react with lipids of cell membranes and the impairment of these membranes may cause RP.Therefore we examined the changes of lipids of irradiated mices lungs and compared with pathological changes.
Then experimentaly lipids peroxidation in irradiated mices lungs both in vitro and in vivo was analyzed and main fatty acids of lungs were quantified by gas chromatogrphy/mass spectrometry (GC/MS). The total of all lipids of pulmonary tissue in vitro was decreased dramaticaly by irradiation. And this change was suppressed by antioxidants such as vitamin E and Coenzyme Q10. On the other hand, in vivo these changes were not so clear. But Arachidonic acid and Docosahexanoic acid were also decreased by irradiation and prevented by these antioxidants. These changes were well correlated to pathophysiological findings at 4 weeks after irradiation. So we conclude that RP is mainly related to lipid peroxidation of pulmonary tissue and antioxidants suppress this reaction.