Navigation Links
Enzyme shreds Alzheimer's protein

An enzyme found naturally in the brain snips apart the protein that forms the sludge called amyloid plaque that is one of the hallmarks of Alzheimer's disease (AD), researchers have found. They said their findings in mice suggest that the protein, called Cathepsin B (CatB), is a key part of a protective mechanism that may fail in some forms of AD. Also, they said their findings suggest that drugs to enhance CatB activity could break down amyloid deposits, counteracting one of the central pathologies of AD.

Li Gan and colleagues published their findings in the September 21, 2006, issue of the journal Neuron, published by Cell Press.

Their experiments were prompted by previous studies showing that the cysteine protease CatB--an enzyme that snips apart proteins--closely associated with the amyloid-ß (Aß) protein that forms the amyloid plaques, a hallmark of AD. However, those studies had not determined whether CatB was "good" or "bad"--that is, whether it acted to produce Aß from a longer protein, called amyloid precursor protein (APP), or whether it broke down Aß.

In their experiments, Gan and colleagues determined that CatB was the latter--breaking down Aß, apparently to enable other enzymes to further degrade the protein for the cell's protein "garbage deposal" system.

They found that knocking out the CatB gene increased plaque deposition in a mouse model of AD in which mice expressed the human form of APP. They also found that CatB tended to accumulate within amyloid plaques and that it acted to reduce Aß levels in neurons. And they found that introducing a pathological form of Aß, called Aß1-42, into neurons increased CatB in young and middle-aged mice with human APP, but not old mice. "Thus, upregulation of CatB may represent a protective mechanism that fails with aging," wrote the researchers, and such failure may play a role in late-onset sporadic AD.

Their test tube studies showed that CatB biochemically degrades Aß by snipping one end of the protein, called the C-terminal end. What's more, the enzyme also degrades the long strings of Aß that form amyloid plaque, they found.

Finally, they found that increasing levels of CatB in aging mice with human APP markedly reduced plaque deposits in the animals' brains.

Gan and colleagues concluded that "our findings suggest that inhibition or loss of CatB function could interfere with its protective function and promote the development of AD, whereas overexpression of CatB could counteract Aß accumulation and aggregation. Thus, pharmacological activation of CatB could downregulate Aß1-42 assemblies through C-terminal truncation, offering an approach to the treatment of AD."
'"/>

Source:Cell Press


Related biology news :

1. Enzyme, lost in most mammals, is shown to protect against UV-induced skin cancer
2. Novel Enzyme Shows Potential As An Anti-HIV Target
3. Enzyme allows B cells to resist death, leading to leukemia
4. Enzyme shown to help protect genomic stability
5. Measuring Enzymes At End Of Cancer Pathway Predicts Outcome Of Tarceva, Taxol
6. Enzymes newly discovered role may make it target for arthritis treatment
7. Promiscuous Catalytic Activity Possessed by Novel Enzyme Structure
8. Gene Bridges And Covalys To Develop Restriction-Enzyme-Free SNAP-tag Gene Fusion Kits
9. Newly Discovered Role for Heart Response Enzyme May Yield Better Heart Failure Therapy
10. Enzyme affects hypertension by controlling salt levels in body
11. Enzyme inhibitors block replication of SARS virus

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:1/18/2017)...  In vitro diagnostic (IVD) companies were very active ... and Kalorama Information expects that trend to continue – ... Generally, uncertainty in reimbursement and healthcare reform in ... the acquisitions landscape. Instead of looking to buy technology, ... outside of their home country and also to increase ...
(Date:1/12/2017)... 12, 2017 A new report by Allied Market Research, titled, ... biometric technology market is expected to generate revenue of $10.72 billion by 2022, with ... Continue Reading ... Allied Market Research Logo ...      (Logo: http://photos.prnewswire.com/prnh/20140911/647229) In the ...
(Date:1/6/2017)... , Jan. 5, 2017  Delta ID Inc., a ... scanning technology for automotive at CES® 2017. Delta ID ... ) to demonstrate the use of iris scanning as ... authenticate the driver in a car, and as a ... driving experience. Delta ID and Gentex will ...
Breaking Biology News(10 mins):
(Date:1/19/2017)... Jan. 19, 2017 AquaBounty Technologies, Inc. (AIM: ... productivity in aquaculture and a majority-owned subsidiary of Intrexon ... has completed the listing of its common shares on ... from Intrexon. "AquaBounty,s listing on NASDAQ represents ... our exposure to the U.S. markets as we advance ...
(Date:1/19/2017)... ... January 18, 2017 , ... LabRoots ... scientists from around the world, was today awarded the "Best Science & Technology ... entirely on merit and decided upon by a dedicated team of researchers and ...
(Date:1/19/2017)... ... January 19, 2017 , ... ... spanning the full spectrum of drug and device development, and Prism Clinical ... companies and clinicians, today announced Verified Clinical Trials (VCT) has been ...
(Date:1/19/2017)...  Northwest Biotherapeutics, Inc. (OTCQB: NWBO) ("NW Bio"), a ... operable and inoperable solid tumor cancers, announced today that ... NW Bio, will present at the Phacilitate Immunotherapy World ... Regency Hotel in Miami, Florida . ... "New Therapeutic Approaches – Expanding the Reach of Cancer ...
Breaking Biology Technology: