Stanford researcher Joseph Garner, PhD, who is a great lover of mice, has an interesting new theory about why drugs tested in these endearing little creatures often don't end up working in people. The problem, quite simply, is that mice in research labs are cold.
The cold temperatures are mandated by the government, as otherwise the mice would become uncontrollably aggressive. But the cold also affects the animals' physiology and thus could compromise research results, says Garner, whose work is focused on the well-being of the mouse.
From our release:
"If you want to design a drug that will help a patient in the hospital, you cannot reasonably do that in animals that are cold-stressed and are compensating with an elevated metabolic rate," Garner said. "This will change all aspects of their physiology - like how fast the liver breaks down a drug - which can't help but increase the chance that a drug will behave differently in mice and in humans."
His latest study, published today in PLoS ONE, offers an easy solution: If you give the mice some shredded paper, they'll happily build a nest to naturally warm themselves. After all, nesting is what mice normally do in the wild, he notes. To test the theory, he and his colleagues put mice in environments with varying temperatures and amounts of nesting material. The mice could move between the cages and/or gather the nesting material, according to their whim.
The animals routinely chose to build a nest to temper the chill, as well as provide them with a sense of security, Garner says. That is good for researchers, too, as nest-building makes the animals easier to observe:
"The shape of the nest tells an experienced person whether the animals are too hot or too cold, whether they are sick or whether they are about to give birth," Garner said. "Once you learn how to 'speak mouse nest,' the nest is a wonderful tool that anyone can use to assess the general state of the mouse."
Photo by Brianna Gaskill