Paul Bernstein, MD

University of Utah School of Medicine Professor
Department of Ophthalmology and Visual Sciences

Dr. Bernstein studies macular pigment distribution in the eye. One of the earliest signs of MacTel is the abnormal redistribution of macular carotenoid pigments in the eye. Understanding this phenomenon could lead to new treatments for the disease.

Top left: abnormal distribution of macular pigments are seen here as a yellow or darker ring. This is one of the first signs of MacTel. Bottom: evidence that supplementation with lutein or zeaxanthin enhances the ring-shaped pattern but does not normalize the distribution of pigments.

In MacTel eyes, the central region of the retina, the macula, becomes abnormally devoid of macular carotenoid pigments. Typically, macular carotenoid pigments are bound in place by carotenoid binding proteins. Dr. Bernstein’s laboratory has explored the physiology of carotenoid binding proteins and metabolic enzymes that influence pigment production. His research includes the retina and the cells that support the retina, the retinal pigment epithelium (RPE).

Dr. Bernstein’s laboratory collaborates with the Fruttiger Laboratory to look for binding protein mislocalization in tissue sections from MacTel donor eyes. His laboratory also uses confocal resonance Raman imaging in tissue sections of normal and MacTel donor eyes to localize the macular carotenoid pigments with high resolution and chemical specificity in order to understand how and why this redistribution occurs early in the course of MacTel.

The Bernstein Laboratory recently completed a two-year interventional study of zeaxanthin supplementation in eight Utah MacTel subjects to investigate whether including carotenoids in the diet can repopulate the central retina with pigments. They found that supplementation with this carotenoid enhances the anomalous ring of macular pigment but fails to fill in the central portion of the ring. This implies that the center of the MacTel retina is missing functional zeaxanthin binding proteins.