Macular pigment carotenoids in the retina and occipital cortex are related in humans.
OBJECTIVE
Lutein and zeaxanthin are dietary carotenoids that preferentially accumulate in the macular region of the retina. Together with meso-zeaxanthin, a conversion product of lutein in the macula, they form the macular pigment. Lutein is also the predominant carotenoid in human brain tissue and lutein status is associated with cognitive function in adults. The study objective was to evaluate the relationship between retinal and brain lutein and zeaxanthin in humans.


METHODS
Donated brain tissue (occipital cortex and hippocampus) and matched retina were obtained from the National Disease Research Interchange, a national human tissue resource center which adheres to strict consent and confidentiality procedures. Decedents were men and women aged >50 years who either had normal cognitive function or Alzheimer's disease. Tissues were analyzed using standard lipid extractions followed by analysis on reverse-phase high performance liquid chromatography (HPLC) and normal-phase HPLC (for meso-zeaxanthin).


RESULTS
Macular pigment carotenoids (lutein, meso-zeaxanthin, and zeaxanthin combined) in the retina were significantly related to the combined concentrations of lutein and zeaxanthin in the occipital cortex. When analyzed separately, only retinal lutein (plus meso-zeaxanthin), not zeaxanthin, was significantly related to lutein in the occipital cortex. No correlations were observed with lutein and zeaxanthin in the hippocampus.


CONCLUSIONS
Total macular pigment density measured via non-invasive, psychophysical techniques can be used as a biomarker to ascertain brain lutein and zeaxanthin status in clinical studies.
a Antioxidants Research Lab , Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University , Boston , MA , USA.
Rohini
R
Vishwanathan
b DSM Nutritional Products Ltd , Kaiseraugst , Switzerland.
Wolfgang
W
Schalch
a Antioxidants Research Lab , Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University , Boston , MA , USA.
Elizabeth J
EJ
Johnson
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D003071:Cognition; D005260:Female; D006624:Hippocampus / Q000378:metabolism; D006801:Humans; D014975:Lutein / Q000302:isolation & purification / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000378:metabolism*; D009928:Organ Specificity; D015203:Reproducibility of Results; D012160:Retina / Q000378:metabolism*; D012168:Retinal Pigments / Q000302:isolation & purification / Q000378:metabolism*; D014015:Tissue Banks; D014793:Visual Cortex / Q000378:metabolism*; D065146:Zeaxanthins / Q000302:isolation & purification / Q000378:metabolism*
D015415:Biomarkers; D012168:Retinal Pigments; D065146:Zeaxanthins; C584722:meso-zeaxanthin; D014975:Lutein
Brain; Cognition; Lutein; Macular pigment; Meso-zeaxanthin; Retina; Zeaxanthin