Measuring C. elegans Ageing Through Non-Invasive Monitoring of Movement across Large Populations

Abstract

Finding new interventions that slow ageing and maintain human health is a huge challenge of our time. The nematode Caenorhabditis elegans, offers a rapid in vivo method to determine whether a compound extends its 2-3 week lifespan. However, the standard C. elegans lifespan assay is hard to scale for large screens. Lifespan analysis produces only one data point per animal with no information about health. Here we describe automated monitoring of movement from early to mid-adulthood as a healthspan-based alternative to measure ageing. Using our WormGazer technology, over 100 petri dishes containing C. elegans worms are imaged simultaneously and non-invasively by an array of cameras. This approach demonstrates that most functional decline in C. elegans occurs during the first week of adulthood. We find 7 days of imaging is sufficient to measure the dose-dependent efficacy of sulfamethoxazole to slow ageing, compared to 40 days required for a parallel lifespan experiment. Understanding any negative consequences of interventions that slow ageing is important. We show that the long-lived mutant age-1(hx546) stays active for longer than the wild type but it moves slower in early adulthood. Thus, continuous analysis of movement can rapidly identify interventions that slow ageing while simultaneously revealing any negative effects on health.