Cover Page»
:: How to recognise Neurocanthocytosis

The first signs of the diseases in the neuroacanthocytosis (NA) group are subtle and easily overlooked. Initial symptoms, which often occur in the person’s mid 20’s, may include grunts or tic noises made unconsciously in the throat, progressing to drooling and problems in controlling the tongue from ejecting food. Involuntary biting of the tongue, lips and/or cheeks may follow.

At the beginning there can be a general, slight physical awkwardness. Things on a shelf are knocked off for no apparent reason. Difficulty with walking and balance can also be early symptoms. Problems controlling trunk, leg and arm movements are often barely noticeable at the beginning, but become increasingly difficult as the disease progresses. Several patients find it difficult to sleep at night and others report fatigue and weakness.

Personality change may also be an early indication. The carefree young adult becomes obsessive-compulsive and uncharacteristically forgetful or just loses confidence or drive. Fainting or epileptic seizures may also occur. Mood changes may happen and a person often becomes isolated, in part out of embarrassment.

There are several reports of the problems beginning after a traumatic event including physical attack, unexpected failure of an exam and birth of a child.

CLINICAL SIGNS

A defining symptom that is not apparent is the spiky red blood cells, or acanthocytes, from which the NA disease group takes its name. These unusual blood cells can be observed with a microscope in some circumstances. Still more difficult to observe are the alterations or mutations in patients’ genes. Each of the NA group diseases has a different genetic characteristic that can be determined only by blood tests.

A person showing some of this pattern of symptoms should see a neurologist. Clinicians and patients can also visit www.naadvocacy.org for links to further scientific reports. Full details are also available on the free blood testing service offered by the Advocacy for Neuroacanthocytosis Patients, aimed at helping determine a definitive diagnosis for NA.



:: Useful NA Resources

  • Neuroacanthocytosis Syndromes II, published December 2007, the book provides a profound insight into recent developments within the field of neuroacanthocytosis syndromes. Edited by Ruth H. Walker, Shinji Saiki and Adrian Danek. Available at amazon.com
  • A Western blot test for the presence of chorein in the membranes of red blood cells can be offered free of charge due to support of the Advocacy for Neuroacanthocytosis Patients'. Download instructions on the blood sampling and specimen shipment as a PDF or get more information on the method at PubMed
  • The entry for chorea acanthocytosis in GeneReviews is the most complete, readily available report on ChAc. Published by the University of Washington with the support of the National Institutes of Health
  • A dedicated Patient & Families Support Group at Yahoo Groups offers patients and families information, advice, support or just an understanding ear
  • Visit PubMed for access to NA research in English from the Medline database.
  • Search Google for the latest on NA
  • Visit the NA page on WeMove, the Movement Disorder Societies charitable and educational associate



:: naadvocacy.org

naadvocacy.org is the website of the The Institute for Neuroacanthocytosis. It is the Advocacy's international centre for supporting patients and promoting clinical and basic research. The website provides access to resources found on the website.

  • Patients' Centre
  • Clinic
  • Library
  • Symposia
  • NA News
  • Research
  • Fundraising


:: Previous Issues
NA News Issue 15

NA News Issue 14

NA News Issue 13
:: Join NA News

NA News

Email Address:
Remove

What do spiky red blood cells have to do with neurodegeneration?

After 10 years, NA researchers have refined their working hypothesis on acanthocytosis in NA patients. Using insights gained at the London/Oxford symposium in 2008, the hypothesis has been refined to: “The anomalies in the red blood cells causing acanthocytosis relate to a malfunction in the membrane that in neurons may hamper normal autophagy and lead to cell death.”


Prof Giel Bosman and Prof Lucia de Franceschii
Prof Giel Bosman and Prof Lucia de Franceschii
The work of Prof Lucia de Franceschi at the University of Verona and Prof Giel Bosman at the University Nijmegen Medical Centre has just been published in the internationally- recognised journal “Blood” (see doi:10.1182/blood-2011-05-355339): Erythrocyte membrane changes of chorea-acanthocytosis are the result of altered Lyn kinase activity.

In May 2002 the First Symposium on Neuroacanthocytosis heard the speculation that functional anomalies in band 3 of cell membranes may be involved in generation of acanthocytes. The earliest research commissioned by the Advocacy began the exploration of the cause. The first step was a small project conducted through Mount Sinai Medical Center in New York where Ruth Walker is Associate Professor.

With the financial support of Carl and Betty Pforzheimer, blood samples of patients were analysed by Prof Bosman at the University Nijmegen Medical Centre, Nijmegen, The Netherlands. Prof. Bosman’s work continued in collaboration with Prof de Franceschi at the University of Verona, Italy. This work received support from foundations of the Leonard Blavatnik Family in 2008. The investigation was incorporated into the European Multidisciplinary Investigation into Neuroacanthocytosis (EMINA).

Profs de Franceschi and Bosman report that the significance of their investigation is a novel mechanism for generation of acanthocytes in ChAc.

Using an integrated proteomic approach, the researchers found 'instability' of band 3 junctional complexes bridging the membrane to the cytoskeleton of ChAc red cells. The research found increased tyrosine-phosphorylation of band 3 together with several membrane proteins leading to altered linkage of band 3 to the junctional complexes in ChAc red cells. The researchers then looked at the signalling pathway towards band 3 and found abnormal activation of Lyn, a kinase from the Src family, independently of the canonical Syk-mediated pathway described in red cells from healthy donors. Future studies are planned to study the Lyn-related signalling cascade in ChAc red cells and in other NA disorders by integrated and functional proteomic approaches.

Lyn and Syk as tyrosine kinases belong to the larger class of protein kinases which attach phosphate groups to other amino acids. They function as "on" or "off" switches in many cellular functions". Phosphorylation of proteins by kinases is an important mechanism in communicating signals within a cell and regulating activity of cells such as circulating red blood cells or stationary nerve cells.

Share | 0 Comments | Post a Comment