Worm study shows antidepressant may lengthen life

By Maggie Fox, Health and Science Editor

WASHINGTON (Reuters) - An antidepressant may help worms live longer by tricking the brain into thinking the body is starving, U.S. researchers reported on Wednesday.

The drug, called mianserin, extended the life span of the nematode Caenorhabditis elegans by about 30 percent, the researchers reported in the journal Nature. They hope to find out if the same mechanism can help people live longer.

Three other compounds, including another antidepressant, have similar effects, said Michael Petrascheck of the Fred Hutchinson Cancer Research Center in Seattle. But the life-extending benefits come at a cost.

"Weight gain and increased appetite seems to be one of the side effects. It is one of the reasons these are not such popular antidepressants," Petrascheck said in a telephone interview.

Many studies have shown that slightly starving certain animals -- reducing how much they eat by about 30 percent -- can cause them to live longer.

It is not entirely clear if this occurs in humans, but researchers are keen to duplicate the beneficial effects of calorie restriction without the misery of going hungry.

Howard Hughes Medical Institute researcher Linda Buck and colleagues were looking for drugs that might do this.

C. elegans is a roundworm, or nematode, much studied because despite its tiny size, its biology is similar to that of humans and other animals.