Dietary restriction in C. elegans: from rate-of-living effects to nutrient sensing pathways.
The nematode Caenorhabditis elegans has been subjected to dietary restriction (DR) by a number of means, with varying results in terms of fecundity and lifespan. Two possible mechanisms by which DR increases lifespan are reduction of metabolic rate and reduction of insulin/IGF-1 signalling. Experimental tests have not supported either possibility. However, interaction studies suggest that DR and insulin/IGF-1 signalling may act in parallel on common regulated processes. In this review, we discuss recent developments in C. elegans DR research, including new discoveries about the biology of nutrient uptake in the gut, and the importance of invasion by the bacterial food source as a determinant of lifespan. The evidence that the effect of DR on lifespan in C. elegans is mediated by the TOR pathway is discussed. We conclude that the effect of DR on lifespan is likely to involve multiple mechanisms, which may differ according to the DR regimen used and the organism under study.
Walker
Glenda
G
Department of Biology, University College London, Gower Street, WC1E 6BT, UK.
Houthoofd
Koen
K
Vanfleteren
Jacques R
JR
Gems
David
D
D018528:ATP-Binding Cassette Transporters / Q000378:metabolism; D000375:Aging; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001692:Biological Transport; D017173:Caenorhabditis elegans; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism / Q000502:physiology; D031204:Caloric Restriction; D004032:Diet; D007328:Insulin / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D008136:Longevity; D008954:Models, Biological; D012964:Sodium / Q000378:metabolism; D017923:Sodium-Hydrogen Exchangers / Q000378:metabolism; D014451:Ubiquinone / Q000737:chemistry
D018528:ATP-Binding Cassette Transporters; D029742:Caenorhabditis elegans Proteins; D007328:Insulin; C480043:NHX-2 protein, C elegans; D017923:Sodium-Hydrogen Exchangers; C113070:pept-1 protein, C elegans; D014451:Ubiquinone; D007334:Insulin-Like Growth Factor I; D012964:Sodium