Navigation Links
Alzheimers Disease Enzyme may Interfere With Brain Function

An enzyme involved in the formation of the amyloid-beta protein associated with Alzheimers disease can also alter the mechanism by which signals are transmitted between brain cells , the disruption of which can cause seizures.

These findings from researchers at the MassGeneral Institute for Neurodegenerative Disorders may explain the increased incidence of seizures in Alzheimers patients and suggest that potential treatments that block this enzyme called beta-secretase may alleviate their occurrence.

Alzheimer's disease is characterized by plaques within the brain of the toxic amyloid-beta protein. Amyloid-beta is formed when the larger amyloid precursor protein (APP) is clipped by two enzymes BACE and gamma-secretase which releases the amyloid-beta fragment.

Signaling impulses in nerve cells are transmitted via voltage-gated sodium channels, structures on the cell membrane that transmit electrochemical signal by admitting charged sodium particles into the cells interior. Sodium channels consist of an alpha subunit, which makes up the body of the channel, and one or two beta subunits that help to regulate the channels activity.

Previous studies from Kovacs team and others showed that the BACE and gamma-secretase enzymes that release amyloid-beta from APP also act on the beta2 subunit of neuronal sodium channels. The current study was designed to examine how this processing of the beta2 subunit may alter neuronal function.

Lead author Doo Yeon Kim, PhD, and colleagues first confirmed that the beta2 subunit, similar to APP, can be acted on by BACE and gamma-secretase, releasing a portion of the beta2 molecule from the cell membrane.

A series of experiments using brain tissue from animal models and from Alzheimers patients revealed the following series of cellular events: Elevated levels of the free beta2 segment within the cell appear to increase production of the alpha subunits, but those molecules are not incorporated into new sodium channels on the cell surface. The resulting deficit of membrane sodium channels inhibits the passage of neuronal signals into and through the cells.

Neuronal sodium-channel dysfunction is known to cause seizures in both mice and humans. In a supplement to the current paper the investigators present evidence that sodium channel metabolism is altered in the brains of Alzheimers patients compared with non-demented individuals of similar age.

Our study suggests that the BACE inhibitors currently being developed to reduce amyloid-beta generation in Alzheimers disease patients may also help prevent seizures by alleviating disrupted neural activity, Kovacs explains. However, complete inhibition of BACE activity could interfere with the enzymes normal regulation of sodium channels, so therapeutic strategies using those inhibitors will need to be carefully designed.


'"/>




Related medicine news :

1. Testing genes for disease does not cause harm to children of people with Alzheimers
2. Age-Dependent Alterations Not Specific For Alzheimers Disease
3. Killing two birds (cholesterol and Alzheimers disease) with the same stone
4. Exposure To High Aluminum Levels In Tap Water Lead To Rare Form Of Alzheimers
5. Sugar variant may make a world of difference to Alzheimers disease
6. Cancer Causing Protein May Heal Alzheimers
7. Emotional Stress Could Be a Factor in Causing Alzheimers: Study
8. Alzheimers Incidence is Set to Quadruple by 2050
9. GAB2-A New Alzheimers Gene Identified
10. Reduced Oxygen to the Brain Increases Alzheimers Risk in Stroke Victims
11. Magnets to the rescue of Alzheimers patients
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/27/2016)... ... June 27, 2016 , ... A ... revolutionize the emergency ambulance transport experience for the millions of people who require ... has disrupted the taxi industry through the use of technology. Now, SmartEMS has ...
(Date:6/26/2016)... ... June 26, 2016 , ... PawPaws brand pet ... product that was developed to enhance the health of felines. The formula is all-natural ... two main herbs in the PawPaws Cat Kidney Support Supplement Soft Chews ...
(Date:6/25/2016)... FL (PRWEB) , ... June 25, 2016 , ... The temporary closing of Bruton Memorial ... Plant City Observer , brings up a new, often overlooked aspect of head lice: the ... closing for fumigation is not a common occurrence, but a necessary one in the event ...
(Date:6/25/2016)... ... ... On Friday, June 10, Van Mitchell, Secretary of the Maryland Department of Health ... of their exemplary accomplishments in worksite health promotion. , The Wellness at Work Awards ... at the BWI Marriott in Linthicum Heights. iHire was one of 42 businesses to ...
(Date:6/24/2016)... , ... June 24, 2016 , ... Marcy was in a crisis. Her son James, ... out at his family verbally and physically. , “When something upset him, he couldn’t control ... use it. He would throw rocks at my other children and say he was going ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... Research and Markets has announced the addition of the ... offering. The current unmet ... for MedImmune to enter. The US ageing population creates a ... considerable growth for effective anti-influenza medications. The introduction of a ... development is still in its infancy. Key ...
(Date:6/23/2016)... PARK RIDGE, Ill. and INDIANAPOLIS ... caliber of students receiving a Lilly Diabetes Tomorrow,s Leaders ... hands. The 2016 scholarship winners, announced today online at ... refused to let type 1 diabetes stand in the ... Lilly Diabetes has supported the Foundation,s scholarship program since ...
(Date:6/23/2016)... 2016  Guerbet announced today that it has been ... Award . One of 12 suppliers to ... its support of Premier members through exceptional local customer ... commitment to lower costs. ... our outstanding customer service from Premier," says Massimo ...
Breaking Medicine Technology: