Cat food-linked illness yields clues to MS

Cat food could be the unlikely inspiration for important insights into multiple sclerosis and other afflictions of the central nervous system, scientists say. While looking into why pregnant cats on a special diet of irradiated food began to have problems with movement, including paralysis and vision, University of Wisconsin-Madison researchers found that the felines' nerve fibers had lost the fatty myelin insulation that helps signals pass along these axons. Once off the diet, though, the cats' bodies reestablished thinner myelin sheaths that allowed the cats to recover fully, but slowly. "The fundamental point of the study is that it proves unequivocally that extensive remyelination can lead to recovery from a severe neurological disorder," lead researcher Ian Duncan, a professor of medical sciences at the university's School of Veterinary Medicine and an authority on demyelinating diseases, said in a news release from the university. "It indicates the profound ability of the central nervous system to repair itself," he said. The finding, published in the March 30 issue of Proceedings of the National Academy of Sciences, would suggest that people with MS and similar nerve disorders in which myelin has degraded -- but the nerves are still functioning -- might benefit from treatment aimed at rebuilding the fatty substance. Loss of the myelin covering on axons can lead to loss of feeling, movement, cognition and other nerve-related functions in humans. The nerve condition the cats developed, while similar to myelin-related diseases in humans, could not be classified. Duncan, who was not involved in the original cat food study, said the exact cause of the cats' condition was not determined, but he thought it was a "species specific" malady and that it was "extremely unlikely" that irradiated food posed a problem to humans. "The key thing is that it absolutely confirms the notion that remyelinating strategies are clinically important," Duncan said.