Linked Life Data

15679103

Source:http://linkedlifedata.com/resource/pubmed/id/15679103

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2005-1-31
pubmed:abstractText
Autophagy (which includes macro-, micro-, and chaperone-mediated autophagy) is an important biological mechanism for degradation of damaged/obsolete macromolecules and organelles. Ageing non-dividing cells, however, progressively accumulate oxidised proteins, defective organelles and intralysosomal lipofuscin inclusions, suggesting inherent insufficiency of autophagy. To learn more about the role of macroautophagy in the turnover of organelles and lipofuscin formation, we inhibited autophagic sequestration with 3-methyladenine (3 MA) in growth-arrested human fibroblasts, a classical model of cellular ageing. Such treatment resulted in a dramatic accumulation of altered lysosomes, displaying lipofuscin-like autofluorescence, as well as in a moderate increase of mitochondria with lowered membrane potential. The size of the late endosomal compartment appeared not to be significantly altered following 3 MA exposure. The accumulation of lipofuscin-like material was enhanced when 3 MA administration was combined with hyperoxia. The findings suggest that macroautophagy is essential for normal turnover of lysosomes. This notion is supported by reports in the literature of lysosomal membrane proteins inside lysosomes and/or late endosomes, as well as lysosomes with active hydrolases within autophagosomes following vinblastine-induced block of fusion between lysosomes and autophagosomes. The data also suggest that specific components of lysosomes, such as membranes and proteins, may be direct sources of lipofuscin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0171-9335
pubmed:author
pubmed:issnType
Print
pubmed:volume
83
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
583-90
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Inhibition of autophagy with 3-methyladenine results in impaired turnover of lysosomes and accumulation of lipofuscin-like material.
pubmed:affiliation
Division of Pathology II, Department of Neuroscience and Locomotion, Faculty of Health Sciences, Linköping University, Sweden. yurst@inr.liu.se
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't