Lipofuscin can be eliminated from the retinal pigment epithelium of monkeys.

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Neurobiol Aging. 2012 Jan 12. [Epub ahead of print]
Lipofuscin can be eliminated from the retinal pigment epithelium of
monkeys.
Julien S, Schraermeyer U.
SourceSection of Experimental Vitreoretinal Surgery, Centre for
Ophthalmology, Tübingen, Germany.

Abstract
Lipofuscin is a cytologic hallmark of aging in metabolically active
postmitotic cells including neurons, cardiac muscle cells, and the
retinal pigment epithelium (RPE). High levels of lipofuscin are
involved in the pathogenesis of age-related macular degeneration
(AMD), the main cause of blindness in the elderly population in the
western world. Degradation and exocytosis of lipofuscin by RPE cells
have not been observed in vivo until now, and no drug is known to
eliminate the intracellular amount of lipofuscin. Here, we show that
in monkeys treated with a small molecule belonging to the
tetrahydropyridoethers class (n = 36 of 48 monkeys), RPE cells
significantly release lipofuscin. In 4 eyes, macrophages were detected
which had taken up lipofuscin. They were located between the Bruch's
membrane and the RPE, and in the choroid. The quantification of
pigment granules was performed by transmission electron microscopy.
Our findings open the way to develop therapeutic strategies to remove
lipofuscin from RPE cells, which may have implications for the
treatment of age-related macular degeneration in which lipofuscin
accumulation in cells is a causative factor.

Copyright © 2011 Elsevier Inc. All rights reserved.

PMID:22244091[PubMed - as supplied by publis