Groundbreaking work at 'the Neuro'

Exciting new breakthroughs include evidence for a link between chronic fatigue and MS

By Joshua Karpati

Probably the most important factor behind the success of the Montreal Neurological Institute (MNI) is its unique affiliation with the Montreal Neurological Hospital. The two-way flow of information between the bedside and lab bench at the 'Neuro' ? as the two institutions are collectively known ? is distinct and has helped define the focus of researchers and clinicians alike.

Affiliated with McGill University, the MNI has been at the forefront of research on the brain and nerves for the past 70 years. Founded in 1934 by famed neurosurgeon Wilder Penfield, its faculty has grown to over 75 members and several hundred researchers and staff. The MNI primarily conducts research on diseases of the nervous system, including stroke, migraine, myasthenia gravis and epilepsy. Here's a summary of the research being done, beginning with the groundbreaking work on chronic fatigue in multiple sclerosis (MS).

CHRONIC FATIGUE & MS
The value of the Neuro's back and forth is most evident in the work of Dr Douglas Arnold, head of the Clinical Research Unit. He and his team recently published a breakthrough study in the Archives of Neurology, which details strong evidence linking extreme fatigue that plagues most multiple sclerosis (MS) sufferers to nerve damage in the white matter of the brain.

Previous attempts at linking fatigue with the visible manifestation of the disease ? the volume of MS lesions in the brain ? were unsuccessful. Dr Arnold's work uses a technique called magnetic resonance spectroscopy (MRS), which employs the same MRI equipment used to obtain structural information on tissue pathology, except that MRS gathers information at the chemical level. MRS has enabled Dr Arnold's team to analyze N-acetylaspartate, a chemical only found in nerve fibres (axons). Any change in concentration of this compound indicates compromise in nerve function. "The brain looks 'normal,' but this technique shows that is not the case," says Dr Arnold. "It's this neuronal damage that correlates strongly with fatigue in MS patients."

The linkage sheds light on the mechanism of fatigue. "The amount of brain tissue you have to use to perform a specific task or function goes up as the amount of axon loss increases," Dr Arnold points out. He distinguishes widespread neuronal damage, which greatly compromises brain integrity, from the focal injuries caused by lesions. Due to the crippling of nerve function in neuronal damage, "the ability to perform any individual task, like tapping a finger, takes far greater motor or cognitive exertion."

The strength of the evidence collected in the study was not entirely expected. Dr Arnold admits, "We were a little surprised ? pleasantly surprised ? when we worked out how well the data correlated. We knew beforehand that neuronal integrity was affected, but the extent and severity of the connection was not known." This discovery offers hope for all chronic fatigue sufferers, not just those with MS.

PROTEOMICS
Dr Peter McPherson and his team have published a piece in the Proceedings of the National Academy of Sciences detailing their research into proteomics ? the mechanical workings of molecules. One insight generated by their work is how defective uptake of cholesterol into cells leads to high blood cholesterol levels.

PARKINSON'S DISEASE
Important discoveries about the processes by which certain nerve cells are destroyed in Parkinson's disease are being made by Dr Edward Fon. He and his team focus on the roles of two particular proteins, parkin and synnuclein. Abnormalities in these molecules cause disabling symptoms in Parkinson's patients.