Enzyme may be a key to Alzheimer's-related cell death

Oct 06, 2009
Enzyme may be a key to Alzheimer's-related cell death
Sandra Rossie found that an enzyme blocks a mechanism that can lead to neural cell death. (Purdue Agricultural Communication photo/Tom Campbell)

(PhysOrg.com) -- A Purdue University researcher has discovered that the amount of an enzyme present in neurons can affect the mechanism thought to cause cell death in Alzheimer's disease patients and may have applications for other diseases such as stroke and heart attack.

Sandra Rossie, a professor of biochemistry, found that increasing the amount of protein phosphatase 5, or PP5, in rat neural cells resulted in less cell death associated with , which chemically damage cell molecules. Conversely, decreasing PP5 caused greater cell death. The results of Rossie's study are published in the early online version of The Journal of Neurochemistry.

Alzheimer's, a degenerative neurological disease affecting around 5 million people, results in and dementia. One theory on the cause of Alzheimer's is that overproduction of certain forms of amyloid beta protein by neurons leads to the generation of reactive oxygen species, which activate stress pathways.

"If stress pathways remain active for a prolonged period, the cell will die," Rossie said.

Rossie's lab found that PP5 overexpression prevents neuronal death by amyloid beta and shuts off the stress pathways. When reactive oxygen that wasn't created by amyloid beta was used on the cells, the results were the same. In contrast, neurons with reduced PP5 are more sensitive to death caused by amyloid beta.

"That suggests to us that PP5 protects neurons from cell death induced by reactive oxygen species, not just the presence of amyloid beta," Rossie said. "This means that PP5 may protect against other health problems involving reactive oxygen species as well, such as stroke and heart attacks."

It is possible, Rossie said, that finding a way to increase PP5 activity could help prevent the loss of neurons by amyloid beta.

Rossie said PP5 also could play a role in inhibiting other responses of neurons to amyloid beta. Her lab will work to determine which pathways PP5 affects, and which of those is most responsible for neural protection by PP5.

Provided by Purdue University (news : web)

Explore further: Research reveals likelihood, onset of MS diagnosis among patients with inflammatory eye disease

add to favorites email to friend print save as pdf

Related Stories

QBI neuroscientists make Alzheimer's disease advance

Jun 10, 2008

Queensland Brain Institute (QBI) neuroscientists at UQ have discovered a new way to reduce neuronal loss in the brain of a person with Alzheimer's disease. Memory loss in people with Alzheimer's disease can be attributed ...

Can tomatoes carry the cure for Alzheimer's?

Jul 08, 2008

The humble tomato could be a suitable carrier for an oral vaccine against Alzheimer's disease, according to HyunSoon Kim from the Korea Research Institute of Bioscience and Biotechnology (KRIBB) in Korea and colleagues from ...

Alzheimer's disease linked to mitochondrial damage

Apr 02, 2009

Investigators at Burnham Institute for Medical Research (Burnham) have demonstrated that attacks on the mitochondrial protein Drp1 by the free radical nitric oxide—which causes a chemical reaction called S-nitrosylation—mediates ...

Anesthesia and Alzheimer's

Apr 25, 2008

In studies of human brain cells, the widely-used anesthetic desflurane does not contribute to increased production of amyloid-beta protein; however, when combined with low oxygen conditions, it can produce more of this Alzheimer’s ...

Researchers find new piece in Alzheimer's puzzle

Feb 25, 2009

Yale researchers have filled in a missing gap on the molecular road map of Alzheimer's disease. In the Feb. 26 issue of the journal Nature, the Yale team reports that cellular prion proteins trigger the process by which ...

Recommended for you

Myelin vital for learning new practical skills

Oct 16, 2014

New evidence of myelin's essential role in learning and retaining new practical skills, such as playing a musical instrument, has been uncovered by UCL research. Myelin is a fatty substance that insulates ...

Reminiscing can help, not hinder, some mind-bending tasks

Oct 16, 2014

To solve a mental puzzle, the brain's executive control network for externally focused, goal-oriented thinking must activate, while the network for internally directed thinking like daydreaming must be turned down to avoid ...

User comments : 0