Aging in a very short-lived nematode.
Aging has been characterised in detail in relatively few animal species. Here we describe the aging process in free-living adults of the parasitic nematode Strongyloides ratti. We find that the phenomenology of aging in S. ratti free-living females, resembles that of the short-lived free-living nematode Caenorhabditis elegans, except that it unfolds far more rapidly. The mean (3.0 +/- 0.1 days) and maximum (4.5 +/- 0.8 days) lifespans of free-living S. ratti females are approximately one quarter of equivalent values for C. elegans. Demographic senescence (a hallmark of aging) was observed in free-living S. ratti, with a mortality rate doubling time of 0.8 +/- 0.1 days (females), compared with 2.0 +/- 0.3 in C. elegans. S. ratti lifetime fertility and lifespan were affected by temperature, and there is an age-related decline in feeding rate and movement, similar to C. elegans, but occurring more quickly. Gut autofluorescence (lipofuscin) also increased with age in S. ratti free-living females, as in aging C. elegans. These findings show that the extreme brevity of life in free-living S. ratti adults, the shortest-lived nematode described to date, is the consequence of rapid aging, rather than some other, more rapid and catastrophic life-shortening pathology.
School of Biological Sciences, University of Bristol, Woodland Road, Bristol, BS8 1UG, UK. mike.gardner@bristol.ac.uk
Michael P
MP
Gardner
David
D
Gems
Mark E
ME
Viney
D000375:Aging / Q000502:physiology*; D000818:Animals; D017173:Caenorhabditis elegans / Q000502:physiology; D005260:Female; D005298:Fertility / Q000502:physiology; D005453:Fluorescence; D008018:Life Cycle Stages / Q000502:physiology; D008136:Longevity / Q000502:physiology; D008297:Male; D010274:Parasitology / Q000379:methods; D013045:Species Specificity; D017170:Strongyloides ratti / Q000502:physiology*