Featured Research

from universities, journals, and other organizations

Blood Pressure Drug May Curb Brain Damage From Alzheimer's, Depression And Schizophrenia

Date:
November 7, 2007
Source:
Oregon Health & Science University
Summary:
A drug used to treat high blood pressure and enlargement of the prostate may protect the brain from damage caused by post-traumatic stress disorder, Alzheimer's disease, depression and schizophrenia. Prazosin, also prescribed as an antipsychotic medication, appears to block the increase of steroid hormones known as glucocorticoids, researchers have found. Elevated levels of glucocorticoids are associated with atrophy in nerve branches where impulses are transmitted, and even nerve cell death, in the hippocampus.

Artist's depiction of electrical impulses transmitted between neurons. Prazosin appears to block the increase of steroid hormones known as glucocorticoids. Elevated levels of glucocorticoids are associated with atrophy in nerve branches where impulses are transmitted, and even nerve cell death, in the hippocampus.

A drug used to treat high blood pressure and enlargement of the prostate may protect the brain from damage caused by post-traumatic stress disorder, Alzheimer's disease, depression and schizophrenia.

Prazosin, also prescribed as an antipsychotic medication, appears to block the increase of steroid hormones known as glucocorticoids, Oregon Health & Science University and Portland Veterans Affairs Medical Center researchers have found. Elevated levels of glucocorticoids are associated with atrophy in nerve branches where impulses are transmitted, and even nerve cell death, in the hippocampus.

The hippocampus is the elongated ridge located in the cerebral cortex of the brain where emotions and memory are processed.

"It's known, from human studies, that corticosteroids are not good for you cognitively," said study co-author S. Paul Berger, M.D., assistant professor of psychiatry and behavioral neuroscience, OHSU School of Medicine and the PVAMC. "We think prazosin protects the brain from being damaged by excessive levels of corticosteroid stress hormones."

The study, titled "Prazosin attenuates dexamethasone-induced HSP70 expression in the cortex," is being presented during a poster session today at Neuroscience 2007, the annual Society for Neuroscience conference in San Diego.

Scientists believe stress activates a neurochemical response in the brain that triggers the release of glucocorticoids in the brain, and that high levels of glucocorticoids in blood serum are associated with such psychiatric conditions as schizophrenia, depression, PTSD and Alzheimer's disease. This mechanism has been linked to decreases in cognitive performance in older people who are not suffering from clinical dementia.

"Our hypothesis is that just being afraid of being blown up all the time means you have high levels of steroids all the time," Berger said, referring to PTSD among military personnel.

Low levels of glucocorticoids have anti-inflammatory effects in the brain, but high levels can trigger inflammatory mechanisms that damage nerve cells by activating an enzyme that causes oxidative stress. Even a single exposure to a high dose of glucocorticoids can be sufficient to damage nerve cells: A previous study showed synthetic glucocorticoid therapy to treat autoimmune disorders such as rheumatoid arthritis can induce mood disorders, including psychosis, and cognitive impairment known as "steroid dementia" in severe forms.

To determine the effects of prazosin, OHSU and PVAMC researchers, led by Altaf Darvesh, Ph.D., formerly of the OHSU Department of Psychiatry, administered a glucocorticoid called dexamethasone to rats, then measured the expression of a protein known as heat shock protein 70, or HSP70, that serves as a marker for neurotoxicity. Pretreatment with prazosin, an alpha-1 receptor antagonist, resulted in "significant" slowing of dexamethasone-induced expression in the cerebral cortex.

"The one thing we don't know for sure is, would you have to get it before you're traumatized," Berger said. "Lots of people have high levels of corticosteroids when they're under stress, so could we give them prazosin ahead of time to protect them from brain damage?"

Berger said future research will continue to look at where and how steroids cause brain damage, and just when prazosin would have to be administered to most effectively protect the brain against damage.

"We just looked at brain damage," he said. "Steroids are known to cause cognitive impairment in both rats and people, so the next step is to see if we can correlate brain damage with cognitive effects and determine if we can protect against brain damage to protect cognition."

The study was funded by the U.S. Department of Veterans Affairs.


Story Source:

The above story is based on materials provided by Oregon Health & Science University. Note: Materials may be edited for content and length.


Cite This Page:

Oregon Health & Science University. "Blood Pressure Drug May Curb Brain Damage From Alzheimer's, Depression And Schizophrenia." ScienceDaily. ScienceDaily, 7 November 2007. <www.sciencedaily.com/releases/2007/11/071106174204.htm>.
Oregon Health & Science University. (2007, November 7). Blood Pressure Drug May Curb Brain Damage From Alzheimer's, Depression And Schizophrenia. ScienceDaily. Retrieved August 28, 2014 from www.sciencedaily.com/releases/2007/11/071106174204.htm
Oregon Health & Science University. "Blood Pressure Drug May Curb Brain Damage From Alzheimer's, Depression And Schizophrenia." ScienceDaily. www.sciencedaily.com/releases/2007/11/071106174204.htm (accessed August 28, 2014).

Share This




More Mind & Brain News

Thursday, August 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Treadmill 'trips' May Reduce Falls for Elderly

Treadmill 'trips' May Reduce Falls for Elderly

AP (Aug. 28, 2014) Scientists are tripping the elderly on purpose in a Chicago lab in an effort to better prevent seniors from falling and injuring themselves in real life. (Aug.28) Video provided by AP
Powered by NewsLook.com
Alice in Wonderland Syndrome

Alice in Wonderland Syndrome

Ivanhoe (Aug. 27, 2014) It’s an unusual condition with a colorful name. Kids with “Alice in Wonderland” syndrome see sudden distortions in objects they’re looking at or their own bodies appear to change size, a lot like the main character in the Lewis Carroll story. Video provided by Ivanhoe
Powered by NewsLook.com
Stopping Schizophrenia Before Birth

Stopping Schizophrenia Before Birth

Ivanhoe (Aug. 27, 2014) Scientists have long called choline a “brain booster” essential for human development. Not only does it aid in memory and learning, researchers now believe choline could help prevent mental illness. Video provided by Ivanhoe
Powered by NewsLook.com
Personalized Brain Vaccine for Glioblastoma

Personalized Brain Vaccine for Glioblastoma

Ivanhoe (Aug. 27, 2014) Glioblastoma is the most common and aggressive brain cancer in humans. Now a new treatment using the patient’s own tumor could help slow down its progression and help patients live longer. Video provided by Ivanhoe
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins