کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1925872 | 1536424 | 2010 | 5 صفحه PDF | دانلود رایگان |
It is thought that direct quenching of singlet oxygen and scavenging free radicals by macular pigment carotenoids is a major mechanism for their beneficial effects against light-induced oxidative stress. Corresponding data from human tissue remains unavailable, however. In the studies reported here, electron paramagnetic resonance (EPR) spectroscopy was used to measure light-induced singlet oxygen generation in post-mortem human macula and retinal pigment epithelium/choroid (RPE/choroid). Under white-light illumination, production of singlet oxygen was detected in RPE/choroid but not in macular tissue, and we show that exogenously added macular carotenoids can quench RPE/choroid singlet oxygen. When the singlet oxygen quenching ability of the macular carotenoids was investigated in solution, it was shown that a mixture of meso-zeaxanthin, zeaxanthin, and lutein in a ratio of 1:1:1 can quench more singlet oxygen than the individual carotenoids at the same total concentration.
Research highlights
► EPR spectroscopy can detect production of singlet oxygen in human RPE/choroid.
► MP carotenoids can quench singlet oxygen generated in human ocular tissue.
► MP carotenoids at a physiological ratio of 1:1:1 quench singlet oxygen best.
Journal: Archives of Biochemistry and Biophysics - Volume 504, Issue 1, 1 December 2010, Pages 56–60