Vitamin E in macular and peripheral tissues of the human eye.
This study was undertaken to investigate the distribution of vitamin E in the macular and peripheral regions of the human retina, retinal pigment epithelium (RPE) and choroid as a function of age. High-performance liquid chromatography (HPLC) was used to measure alpha- and gamma-tocopherol levels quantitatively using tocol as an internal standard. In 57 out of 70 donor eyes (ages 9-104) the macular region was isolated and the tocopherols analyzed. The conventional brush method and a new vortex method were used to isolate the retinal pigment epithelium cells. Similar trends for the vitamin E levels (increase to the 5th decade, decrease after 7th decade) were found for the macular and peripheral retina and for the macular RPE. In the peripheral RPE a slight continuous increase with age was found. The vitamin E levels are higher in the RPE than in the retina, for both macular and peripheral regions. The amounts of vitamin E/mg protein are lower in the macular retina than in the peripheral retina, whereas in the RPE there is no difference in vitamin E content between macular and peripheral regions. A simple method based on a gentle vortex step was found to offer several advantages over the more generally used isolation of RPE cells based on brushing, and there was no difference in recovery of vitamin E in RPE cells when they were isolated by either isolation technique. It was also found that denominators, used to express the values of vitamin E in tissues should, be used with care since age dependent trends in parameters/denominators could be caused by trends in the denominators only.
Department of Chemistry and Biochemistry, Montana State University, Bozeman 59717, USA.
T
T
Friedrichson
H L
HL
Kalbach
P
P
Buck
F J
FJ
van Kuijk
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D002469:Cell Separation / Q000379:methods; D002648:Child; D002829:Choroid / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D008266:Macula Lutea / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000378:metabolism*; D012160:Retina / Q000378:metabolism*; D014810:Vitamin E / Q000378:metabolism*
D014810:Vitamin E