Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2004-12-21
pubmed:abstractText
Restriction of food intake extends lifespan in evolutionarily diverse organisms, including mammals. Dietary restriction (DR) also delays the appearance of ageing-related damage and pathology and keeps organisms in a youthful state for longer. DR has hence been suggested to lower the rate of ageing. Analysis of mortality rates can be used to test this idea. During ageing, mortality rates in general increase, approximately exponentially. Lifespan can be extended either by a reduction in the rate of increase in mortality rate with age or a lowering of the initial rate of mortality. A reduction in the slope of a mortality trajectory has generally been taken to indicate that the rate of ageing has been lowered. Data on the effects of temperature on mortality in Drosophila are in accordance with this idea. Lowered temperature extends lifespan solely by lowering the slope of the mortality trajectory and flies with a hotter thermal history have permanently elevated death rates. In contrast, lowering of the initial rate of mortality has been taken to leave the rate of ageing unaffected. In Drosophila and in mice, but not in rats, DR extends lifespan by lowering the initial mortality rate. In Drosophila, the effect of DR is acute, and mortality rate switches rapidly between DR and control values with the corresponding changes in nutritional regime. DR in Drosophila therefore has no impact upon the rate of ageing. Possible mechanisms by which DR can both delay damage and pathology and yet act acutely to determine mortality rates are discussed. In rodents, some phenotypes associated with DR, including microarray profiles, show rapid switching with changed nutritional regime, pointing to potentially acute effects of DR in mammals.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0047-6374
pubmed:author
pubmed:issnType
Print
pubmed:volume
126
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
35-41
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Dietary restriction, mortality trajectories, risk and damage.
pubmed:affiliation
Department of Biology, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK. l.partridge@ucl.ac.uk
pubmed:publicationType
Journal Article, Review, Research Support, Non-U.S. Gov't