Overexpression of xanthine dehydrogenase extends lifespan in C. elegans

Uric acid is known to act as an antioxidant, and one hypothesis posits that certain primates, including humans, increased their uric acid levels during evolution to extend lifespan. To test whether genetically altering the activity of endogenous uric acid synthesis affects organismal lifespan, we generated transgenic Caenorhabditis elegans overexpressing the xanthine dehydrogenase XDH-1 , an enzyme involved in uric acid production. These transgenic animals displayed a 9-15% increase in lifespan. They also exhibited enhanced resistance to the oxidative stress-inducing agent paraquat, implying that the lifespan extension might be linked to the antioxidant effects of uric acid.