The C. elegans lifespan assay toolkit.

Since the discovery of single gene mutations that double its lifespan, the nematode Caenorhabditis elegans has provided remarkable insights into the biology of aging. The precisely measurable lifespan of worms has proven to be an efficient tool to assess the impact of various genetic, physiological and environmental factors on organismal aging. In this article, we describe methods to set up and monitor experiments to determine worm lifespan. We include procedures used for classical, small-scale lifespan assays that are generally performed on solid media, and review recent advances in high-throughput, automated longevity experiments conducted in liquid culture and microfluidic devices. In addition, tools that help analyze this data to obtain survival statistics are summarized, and C. elegans strains that offer particular advantages for lifespan studies are listed.

The C. elegans healthspan and stress-resistance assay toolkit.

A wealth of knowledge on the genetic mechanisms that govern aging has emerged from the study of mutants that exhibit enhanced longevity and exceptional resilience to adverse environmental conditions. In these studies, lifespan has been an excellent proxy for establishing the rate of aging, but it is not always correlated with qualitative measures of healthy aging or 'healthspan'. Although the attributes of healthspan have been challenging to define, they share some universal features that are increasingly being incorporated into aging studies. Here we describe methods used to determine Caenorhabditis elegans healthspan. These include assessments of tissue integrity and functionality and resistance to a variety of biotic and abiotic stressors. We have chosen to include simple, rapid assays in this collection that can be easily undertaken in any C. elegans laboratory, and can be relied on to provide a preliminary but thorough insight into the healthspan of a population.