New approach to Alzheimer’s therapy

	Tweet

The brains of Alzheimer patients have high accumulations of the material beta-amyloid, which appear in the form of plaques. The precursors of these plaques are believed to be the underlying cause of the nerve cell loss that leads to the disruptions in memory that characterize Alzheimer’s disease. The main aim of many Alzheimer therapies is therefore to inhibit the formation of beta-amyloid. Since beta-amyloid is cleaved from the so-called amyloid precursor protein (APP), scientists have focused on stopping the two enzymes that attack the precursor protein. These act like molecular scissors and cut out the beta-amyloid fragment. Blocking these scissors precludes the formation of beta-amyloid.

DZNE and LMU researchers have succeeded in identifying an enzyme known as alpha secretase, which cleaves the amyloid precursor protein (APP) without forming beta-amyloid. Up to this point three different candidates for this function had been under consideration, but the research team has now been able to show that the enzyme ADAM10 alone is responsible for the specific cleavage. Dr. Stefan Lichtenthaler and his team developed highly specific antibodies that can identify the different cleavage products of the precursor protein in the brain cells of mice and in human cell cultures.

Using a special technique called RNA interference, the researchers managed to block each of the three genes that code for the three ADAM enzymes under suspicion. An analysis of the cleavage products revealed that the ADAM10 gene was the only one able to prevent the formation of beta-amyloids. They confirmed their results using mass spectrometry.

"In ADAM10 we have identified a target molecule that plays a central role in the development of the molecular processes in Alzheimer’s disease. We know that ADAM10 is less active in Alzheimer patients,” says Dr. Lichtenthaler. When ADAM10 is less active, the precursor protein is more likely to be cleaved in a way that promotes the formation of beta-amyloids.

“It is possible that less ADAM10 activity could increase susceptibility to Alzheimer’s disease. If that is the case, stimulating ADAM10 could be an important mechanism for therapy. But our antibodies also open up new possibilities for diagnosing and preventing the disease,” says Lichtenthaler. The antibodies could be used to measure ADAM10 activity in spinal fluid and, by extension, identify persons who may have an increased risk of developing Alzheimer’s disease. A series of experiments to examine this possibility is already underway.

###

Publication:

ADAM10 is the Physiologically Relevant, Constitutive Alpha-Secretase of the Amyloid Precursor Protein in Primary Neurons.
Peer-Hendrik Kuhn, Huanhuan Wang, Bastian Dislich, Alessio Colombo, Ulrike Zeitschel, Joachim W. Ellwart, Elisabeth Kremmer, Steffen Roßner, and Stefan F. Lichtenthaler, EMBO Journal, published online, 30 July 2010 doi:10.1038/emboj.2010.167

Contact:

Dr. Stefan Lichtenthaler
German Centre for Neurodegenerative Diseases (DZNE)
Tel.: +49 89 2180 754 53
E-mail:

Sonja Jülich-Abbas
German Centre for Neurodegenerative Diseases (DZNE)
Head of PR
Tel.: +49 228 4330 2260
Mobile: +49 172 2838 930
E-mail:

RELATED STORIES:
Short Stressful Events May Improve Working Memory   Two Biomarkers Improve Prediction of Stroke Risk   Prolonged fasting increases risk of rare type of stroke   Novel Gene Therapy Treatment for Parkinson’s Disease Shows Promise   Demystifying Meditation – Brain Imaging Illustrates How Meditation Reduces Pain   New studies shed light on stroke prevention and management   Less chance of Alzheimer’s when you follow a Mediterranean diet   Alzheimer’s Disease Linked to Mitochondrial Damage   Parkinson’s disease can impair driving   Eye Health Is Related to Brain Health   Study finds that the same face may look male or female   60 second test could help early diagnosis of common brain diseases

Comments

[ + Post Your Own ]

Now you're in the public comment zone. What follows is not Armenian Medical Network's stuff; it comes from other people and we don't vouch for it. A reminder: By using this Web site you agree to accept our Terms of Service. Click here to read the Rules of Engagement.

There are no comments for this entry yet. [ + Comment here + ]