Caenorhabditis elegans as a Toolkit for Studying Mammalian Aging Pathways

Abstract

During the last few decades the free living soil nematode Caenorhabditis elegans has been highlighted as an important model organism to decipher the role of several conserved signaling pathways in longevity determination. C. elegans is a most effective in vivo model for studying aging due to its cellular complexity and high homology with mammalian biochemical and genetic pathways. Despite its apparent simplicity, lately the nematode C. elegans has been developed into an important model for biomedical research, mostly in the functional characterization of novel drug targets identified using genomics technologies. For many decades, aging was considered to be a passive, entropic process of tissue decline that occurred in a haphazard way. We know now, however, that the aging process, like so many other biological processes, is subject to regulation by classical signaling pathways viz. insulin signaling pathway, mitochondrial pathway etc. Some of these genetic pathways were first of all reported in small, short-lived organisms such as yeast, worms and flies, and a genetic alteration in same pathways turned out to extend lifespan in mammals as well. C. elegans aging mechanism provides a basis to understand how age regulation of a genetic pathway might be conserved between distantly related species. Here we review some aging pathways that are evolutionary conserved and modulates lifespan from worms to mammals viz. Insulin signaling (ILS), Dietary restriction (DR), Mitochondrial respiration and Sirtuin pathway.