The macular carotenoids: A biochemical overview

Biochim Biophys Acta Mol Cell Biol Lipids. 2020 Nov;1865(11):158617. doi: 10.1016/j.bbalip.2020.158617. Epub 2020 Jan 10.

Abstract

Among the more than 750 carotenoids identified in nature, only lutein, zeaxanthin, meso-zeaxanthin, and their oxidative metabolites are selectively accumulated in the macula lutea region of the human retina. These retinal carotenoids are collectively referred to as the macular pigment (MP) and are obtained only through dietary sources such as green leafy vegetables and yellow and orange fruits and vegetables. Lutein- and zeaxanthin-specific binding proteins (StARD3 and GSTP1, respectively) mediate the highly selective uptake of MP into the retina. Meso-zeaxanthin is rarely present in the diet, and its unique presence in the human eye results from metabolic conversion from dietary lutein by the RPE65 enzyme. The MP carotenoids filter high-intensity, short-wavelength visible light and are powerful antioxidants in a region vulnerable to light-induced oxidative stress. This review focuses on MP chemistry, absorption, metabolism, transport, and distribution with special emphasis on animal models used for MP study. This article is part of a Special Issue entitled Carotenoids recent advances in cell and molecular biology edited by Johannes von Lintig and Loredana Quadro.

Keywords: Age-related macular degeneration; Carotenoid; Lutein; Macular pigment; Nutrition; Zeaxanthin.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Carotenoids / chemistry
  • Carotenoids / metabolism*
  • Carotenoids / therapeutic use
  • Carrier Proteins / genetics
  • Glutathione S-Transferase pi / genetics
  • Humans
  • Lutein / chemistry
  • Lutein / metabolism
  • Macula Lutea / metabolism*
  • Macular Degeneration / diet therapy*
  • Macular Degeneration / metabolism
  • Macular Pigment / metabolism
  • Membrane Proteins / genetics
  • Plant Leaves / chemistry
  • Retina / drug effects
  • Retina / metabolism*
  • Vegetables / chemistry
  • Zeaxanthins / metabolism
  • cis-trans-Isomerases / genetics

Substances

  • Carrier Proteins
  • Macular Pigment
  • Membrane Proteins
  • STARD3 protein, human
  • Zeaxanthins
  • Carotenoids
  • GSTP1 protein, human
  • Glutathione S-Transferase pi
  • retinoid isomerohydrolase
  • cis-trans-Isomerases
  • Lutein