The lab rats used in biomedical research are often significantly overweight, says one researcher, and that could skew a scientist's work on a new therapy.
Mark Mattson, chief of the laboratory of neurosciences at the U.S. National Institute on Aging Intramural Research Program, writes in New Scientist that some lab rat strains weigh in at more than a kilogram, roughly double the weight of a healthy rat. As a result, the "flab rats" suffer from hypertension, cholesterol problems and more that could derail a research program.
"We know that some carcinogens are more potent in overweight animals and that couch-potato rodents have an elevated risk of developing tumors," writes Mattson, a fitness buff himself. "In addition, many types of tumor grow more rapidly in animals with unlimited access to food, and certain aspects of metastasis--the process by which tumors spread to new sites in the body--appear to differ between obese and slender mice."
Mattson's not just fretting about cancer research. Fat rats could be responsible for spoiling biomedical research into cardiovascular, neurodegenerative and renal drugs as well.