Apolipoprotein B in cholesterol-containing drusen and basal deposits of human eyes with age-related maculopathy

Am J Pathol. 2003 Feb;162(2):413-25. doi: 10.1016/S0002-9440(10)63836-9.

Abstract

Lipids accumulate in Bruch's membrane (BrM), a specialized vascular intima of the eye, and in extracellular lesions associated with aging and age-related maculopathy (ARM). We tested the hypothesis that ARM and atherosclerotic cardiovascular disease share molecules and mechanisms pertaining to extracellular lipid accumulation by localizing cholesterol and apolipoprotein B (apo B) in BrM, basal deposits, and drusen. Human donor eyes were preserved <4 hours postmortem and cryosectioned. Sections were stained with traditional lipid stains and filipin for esterified and unesterified cholesterol or probed with antibodies to apo B, apo E, and apo C-III. Normal adult retinal pigment epithelium (RPE) was subjected to RT-PCR and Western blot analysis for apolipoprotein mRNA and protein. Esterified and unesterified cholesterol was present in all drusen and basal deposits of ARM and normal eyes. Both apo B and apo E but not apo C-III were found in BrM, drusen, and basal deposits. Fewer macular drusen were stained by traditional lipid stains and apolipoprotein antibodies than peripheral drusen. RPE contained apo B and apo E mRNA and protein. Finding cholesterol and apo B in sub-RPE deposits links ARM with important molecules and mechanisms in atherosclerosis initiation and progression. The combination of apo B mRNA and protein in RPE raises the possibility that intraocular assembly of apo B-containing lipoproteins is a pathway involved in forming cholesterol-enriched lesions in ARM.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Aging
  • Amino Acid Sequence
  • Apolipoprotein C-II
  • Apolipoproteins B / analysis*
  • Apolipoproteins B / genetics*
  • Apolipoproteins C / analysis
  • Apolipoproteins E / genetics
  • Cholesterol / analysis*
  • Female
  • Fluorescent Antibody Technique, Indirect
  • Humans
  • Macular Degeneration / genetics
  • Macular Degeneration / pathology*
  • Male
  • Pigment Epithelium of Eye / metabolism*
  • RNA, Messenger / genetics
  • Reference Values
  • Retinal Drusen / genetics
  • Retinal Drusen / pathology*
  • Reverse Transcriptase Polymerase Chain Reaction

Substances

  • Apolipoprotein C-II
  • Apolipoproteins B
  • Apolipoproteins C
  • Apolipoproteins E
  • RNA, Messenger
  • Cholesterol