Spectroscopic detection of photoproducts in lecithin model system after 8-methoxypsoralen plus UV-A treatment.
Photoreactions of 8-methoxypsoralen (8-MOP) in the presence of synthetic lecithins esterified at the beta-position with linoleic/oleic and gamma-palmitic acid (PCd2/d1pal) have been studied. Following UV-A (320-400 nm) irradiation, the photoproducts separated by thin-layer chromatography are analysed by UV absorption spectroscopy, nuclear magnetic resonance and mass spectroscopy. The new isolated products are lecithin double cyclobutane adducts, PC-(8-MOP)2, fatty acid-8-MOP split adducts from phosphatidylcholine and lecithin adducts with photo-oxidized 8-MOP. The photolysis performed in the presence of 8-MOP is related to the previously reported lecithin cyclobutane adducts with psoralen. A hypothetical scheme of lecithin photolysis under PUVA (psoralen + UV-A) treatment is proposed. We suggest that photolysis of lecithin may have a significant role in the chain of reactions triggered in cell membrane submitted to PUVA treatment.
Waszkowska
E
E
Institute of Biochemistry and Biophysics PAS, Warsaw, Poland.
Zarebska
Z
Z
Poznański
J
J
Zhukov
I
I
D002855:Chromatography, Thin Layer; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008730:Methoxsalen / Q000737:chemistry* / Q000528:radiation effects; D008956:Models, Chemical; D010713:Phosphatidylcholines / Q000737:chemistry* / Q000528:radiation effects; D010782:Photolysis; D013053:Spectrophotometry; D014466:Ultraviolet Rays
D010713:Phosphatidylcholines; D008730:Methoxsalen