Iron In Degenerative Retinal Disease

In the presence of ferritin, visible light induces lipid peroxidation
of the porcine photoreceptor outer segment
Authors: Kentaro Ohishi, Xiao Mei Zhang, Shinichi Moriwaki,
Tadahisa Hiramitsu, Seiichi Matsugo

Journal: Free Radical Research
We studied the synergistic effect of visible light and ferritin on
the lipid peroxidation on a fraction of porcine photoreceptor
outer segment (POS).
Reaction mixtures containing the POS fraction and horse spleen
ferritin were irradiated under white fluorescent light mainly
at 17,000 lx or incubated under dark conditions at 37 degrees C.
The lipid peroxidation was evaluated by both the thiobarbituric
acid method and the ferrous oxidation/xylenol orange method.
The irradiation-induced lipid peroxidation was affected by
some experimental factors such as the irradiation dose and
acidity of the material.
When the irradiation was stopped, the lipid peroxidation was
also stopped; thereafter, the re-irradiation induced lipid
peroxidation.
Moreover, this lipid peroxidation was inhibited by desferrioxamine,
an iron chelator, or by dimethylthiourea, a hydroxyl radical
scavenger, suggesting that the lipid peroxidation involves
hydroxyl radicals generated via the Fenton reaction by iron ion
released from ferritin.
The lipid peroxidation did not take place under dark conditions
or in the absence of ferritin.
This study suggested the possibility that the visible light-induced
lipid peroxidation of the POS fraction in the presence of ferritin
may participate in the etiology of human retinal degenerative
diseases as the human retina is exposed to light for life.

Free radical research. 01/09/2006; 40(8):799-807.
ISSN: 1071-5762
DOI: 10.1080/10715760600555027


Who loves ya.
Tom


Jesus Was A Vegetarian!
http://tinyurl.com/2r2nkh


Man Is A Herbivore!
http://tinyurl.com/a3cc3


DEAD PEOPLE WALKING
http://tinyurl.com/zk9fk