For Worms, It’s a Crisis of Movement in Midlife

As worms enter their twilight years, their bodies become wrinkled and flaccid much like humans’ do, according to an exhaustive study of old age in worms. A team from Rutgers, the State University of New Jersey, reported in the Oct. 24 Nature that youthful specimens of the roundworm Caenorhabditis elegans wriggle around vigorously, but in midlife (six to seven days) an ominous decline begins. By old age (12 to 18 days) even a needle prod elicits only ineffectual twitches.

The apparent reason: Muscles are decaying, much as human muscles lose bulk in later years. Also found in worms were thick, wrinkled hides.

In another worm study in the Oct. 24 Science, UC San Francisco researchers showed they can double the lifespan of C. elegans by switching off certain key genes. Inactivating these genes in a worm’s youth gets in the way of reproduction, but doing so in adulthood avoids this down side, the team said.

“They look great; they’re vigorous,” said biologist Cynthia Kenyon, of UCSF.