Macular pigment carotenoids in the retina and occipital cortex are related in humans

Authors: VISHWANATHAN, ROHINI - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; SCHALCH, WOLFGANG - Dsm Nutritional Products, Ltd; JOHNSON, ELIZABETH - Jean Mayer Human Nutrition Research Center On Aging At Tufts University

Submitted to: Nutritional Neuroscience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/15/2014
Publication Date: 2/6/2015
Citation: Vishwanathan, R., Schalch, W., Johnson, E.J. 2015. Macular pigment carotenoids in the retina and occipital cortex are related in humans. Nutritional Neuroscience. doi: 10.1179/1476830514Y.0000000141.

Interpretive Summary: Lutein and zeaxanthin are dietary pigments (carotenoids) that accumulate in the retina where they are referred to as macular pigment. Lutein is 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 levels in humans. Donated brain tissue and matched retinas were obtained from a human tissue resource. Samples were from men and women older than 50 years. Macular pigment in the retina was significantly related to the concentrations of lutein and zeaxanthin the brain. Macular pigment is a simple and quick measure that can be used to give an indication of brain lutein and zeaxanthin levels.

Technical Abstract: Objectives: Lutein and zeaxanthin are dietary carotenoids that preferentially accumulate in the macular region of the retina. Together with mesozeaxanthin, 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 mesozeaxanthin). Results: Macular pigment carotenoids (lutein, mesozeaxanthin, 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 mesozeaxanthin), not zeaxanthin, was significantly related to lutein in the occipital cortex. No correlations were observed with lutein and zeaxanthin in the hippocampus. Discussion: 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.