In a study published March 30, 2009 in the Proceedings of the National Academy of Sciences, a team of researchers from the University of Wisconsin-Madison reports that the restoration in cats of myelin — a fatty insulator of nerve fibers that degrades in a host of human central nervous system disorders, the most common of which is multiple sclerosis — can lead to functional recovery.
“The fundamental point of the study is that it proves unequivocally that extensive remyelination can lead to recovery from a severe neurological disorder,” says Ian Duncan, the UW-Madison neuroscientist who led the research. “It indicates the profound ability of the central nervous system to repair itself.”
The finding is important because it underscores the validity of strategies to reestablish myelin as a therapy for treating a range of severe neurological diseases associated with the loss or damage of myelin, but where the nerves themselves remain intact.
Myelin is a fatty substance that forms a sheath for nerve fibers, known as axons, and facilitates the conduction of nerve signals. Its loss through disease causes impairment of sensation, movement, cognition and other functions, depending on which nerves are affected.
The new study arose from a mysterious affliction of pregnant cats. A company testing the effects on growth and development in cats using diets that had been irradiated reported that some cats developed severe neurological dysfunction, including movement disorders, vision loss and paralysis. Taken off the diet, the cats recovered slowly, but eventually all lost functions were restored.
… In cats removed from the diet, recovery was slow, but all of the previously demyelinated axons became remyelinated. The restored myelin sheaths, however, were not as thick as healthy myelin, Duncan notes.
… “We think it is extremely unlikely that [irradiated food] could become a human health problem,” Duncan explains. “We think it is species specific. It’s important to note these cats were fed a diet of irradiated food for a period of time.”
I suppose Duncan will be eating irradiated food from now on … since Duncan believes it is unlikely to become a human health problem?