Lipids and lipid metabolism in the eye

Abstract

The vertebrate eye is a complex sensory organ consisting of multiple, distinct tissues, each having its own unique biochemical composition, structure, and physiological function. Key among these are the retina, lens, and cornea, working in concert to bring photons of light into the eye, focus them correctly on the retina, and convert their energy into electrochemical signals that are conveyed to the brain where, ultimately, they are processed into a coherent visual image. Defects in any or all of these tissues, whether inborn or acquired, whether through a disease process or by traumatic injury, can compromise vision and, eventually, may result in complete and irreversible blindness. The study of lipids and lipid metabolism in relation to ocular tissues has not been reviewed heretofore in any single text or organized collection of monographs or review articles. Such discussions are usually relegated to a relatively small subsection of a review article or text that more broadly addresses the biochemistry of the eye or one of its constituent tissues. Yet, lipids and lipid-soluble compounds are essential constituents of the cells and tissues that comprise the eye, and defects in their synthesis, intracellular and extracellular transport, and turnover underlie a variety of signifi cant, common, and often severely debilitating eye diseases. Classical “ grind and fi nd ” lipid composition analyses have given way more recently to detailed lipidomic, metabolomic, and lipid-dependent signaling studies, linking a detailed, quantitative knowledge of lipids