Pathology of the spinal cord in progressive supranuclear palsy
Researchers Professor Francesco Scaravilli, Dr Roberta Vitaliani and Dr Tomaso Scaravilli
Institution Institute of Neurology, University College London;
Duration 6 months (February - November 2000)
Grant £5000 to cover Dr Vitaliani's research costs during her six month visit to England to work with Professor Scaravilli and the team at the Institute of Neurology.
Aim of research
To determine if pathological changes in the spinal cord correlate with the symptoms of PSP.
About the research
Control over the sphincter muscle in the bladder is essential for urinary continence, i.e., the ability to pass urine at will. In PSP as the condition progresses, patients can develop problems controlling their bladder (and bowel) resulting in incontinence.
In earlier work the researchers found that in three patients with PSP, bladder dysfunction correlated with changes in Onufrowicz's (Onuf's) nucleus in the lower spinal cord. Observed changes in Onuf's nucleus(which is known to be involved in sphincter control) included severe cell loss and the presence of neurofibrillary tangles. The researchers concluded that bladder dysfunction and abnormal sphincter electromyography correlated with pathological changes in Onuf's nucleus, and proposed that sphincter abnormalities should be included in the list of possible symptoms of PSP.
In this project, the researchers extended their work to examine the spinal cords of five more patients with PSP to determine the extent of any change and its implication for bladder dysfunction and other symptoms of PSP.
Findings
Examination of the 6thcervical (upper spine), 7th thoracic (middle spine), and 5th lumbar (lower spine) segments of the spinal cord revealed variable degrees of generalized nerve cell loss, and the presence of neurophil threads and tau-positive neurons, some of which were reminiscent of neurofibrillary tangles. Tau-positive neurons were seen at each spinal level and in the three zones (anterior, intermediate and posterior) into which each level was subdivided. Cells with the appearance of neurofibrillary tangles were most common in the intermediate zone. In the motor area (lamina IX) a 47%, 52%, and 32% decrease in cell numbers was found at the three spinal levels respectively, with a 39% loss in the intermedio-lateral column (consisting of autonomic neurons).
What does the outcome of this research mean for people with PSP?
This work resulted in the first report of severe neuronal loss throughout the whole spinal cord in patients with PSP. It provided evidence to support earlier suggestions that changes in the spinal cord might be implicated in the pathogenesis of neck dystonia (the characteristic stiffness/rigidity of the neck region) seen in PSP patients.
How has the research you conducted influenced your career and research direction?
Following Dr Vitaliani's work at the Institute of Neurology in London, she returned to Italy where as a neurologist she runs an out-patient department and looks after patients with PSP and Parkinson's disease. Her experience working at the Institute of Neurology and with some of the world's leading experts in PSP has made her more aware of the full range of affects that PSP can exert on patients.
Publications arising directly from the research
Vitaliani R, Scaravilli T, Egarter-Vigl E, Giometto B, Klein C, Scaravilli F, An SF, Pramstaller PP. The pathology of the spinal cord in progressive supranuclear palsy. J Neuropathol Exp Neurol. 2002; 61(3): 268-74.
National/international presentations given on this work
Italian Neurological society meeting. Rimini 2001 (oral presentation)
Italian Neuropathological Association. Siena 2001 (oral presentation)
American Academy of Neurology Philadelphia 2001 (poster presentation)
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