XML Feed for RxPG News   Add RxPG News Headlines to My Yahoo!   Javascript Syndication for RxPG News

Research Health World General
 Latest Research
  Brain Diseases
  Spinal Cord Diseases
  Demyelinating Diseases
  Neurodegenerative Diseases
  Trigeminal Neuralgia
 Infectious Diseases
 Respiratory Medicine
 Public Health
 Clinical Trials
 Medical News
 Awards & Prizes
 Special Topics
 Odd Medical News
 World News

Last Updated: Aug 19th, 2006 - 22:18:38

Stroke Channel
subscribe to Stroke newsletter

Latest Research : Neurosciences : Stroke

   DISCUSS   |   EMAIL   |   PRINT
Estrogen’s role as anti-oxidant can explain lesser risk of stroke in women
Aug 25, 2005, 22:01, Reviewed by: Dr.

“We want to find out more how estrogen can protect blood vessels in the brain”

Estrogen’s role as an inhibitor of toxic-free radicals in cerebral blood vessels may be a key reason why premenopausal women have a lower stroke risk than men.

According to UC Irvine School of Medicine researchers, estrogen has a powerful and positive influence on women’s health by increasing the energy production efficiency of mitochondria – the tiny power plants that provide cells the energy they need to function. And in doing so, the hormone inhibits the mitochondrial production of free radical oxygen molecules. Previous studies have shown that excessive amounts of these radical elements in the body, through a process called oxidative stress, can damage blood vessels and lead to stroke or degenerative disease.

In the UCI study, Dr. Vincent Procaccio of the Center for Molecular and Mitochondrial Medicine and Genetics and colleagues discovered estrogen receptors in vascular mitochondrial cells. To see how mitochondria functioned with deficient estrogen levels, they removed the ovaries from test rats, which suppressed any hormone influence, and identified a significant increase in radical oxygen molecule levels and a decline in the capacity for mitochondria to produce energy. In rats treated with doses of estrogen, however, vascular mitochondria produced energy more efficiently with lower amounts of damaging free radicals.

“We want to find out more how estrogen can protect blood vessels in the brain,” said Procaccio, also an assistant professor of pediatrics. “And when we gain a fuller understanding, we hopefully can figure out how best to realize potential benefits of hormone replacement therapies. Also, learning the mechanisms by which estrogen is beneficial to brain circulation may give us new ideas about how to protect against stroke.”

Spurred by recent findings of the Women’s Health Initiative, there is growing debate over the effects of estrogen and the risk of cardiovascular disease and stroke. While women aged 30 to 50 have about five times less risk of stroke than men, this difference disappears when women reach menopause. Research studies show that estrogen protects animals from experimental stroke, but recent clinical trials with certain hormone replacement therapies in older women did not show protection from stroke.

Study results appear on the online version of Molecular Pharmacology. Chris Stirone, Sue P. Duckles and Diana N. Krause of the UCI Department of Pharmacology assisted with the study. The National Institutes of Health provided support.

About mitochondria
Mitochondria are the power plants of cells responsible for burning the calories in our diet with the oxygen that we breathe to generate carbon dioxide, water and the energy for our cells. The cellular energy is used for two purposes, to generate heat to maintain our body temperature and to synthesize ATP (adenosine triphosphate), a chemical form of energy which permits us to do work such as exercise, think, write, and make and repair cells and tissues.

When the mitochondria burn our dietary fuel, they also generate a toxic by-product called oxygen radicals, the mitochondrial equivalent to the smoke generated by coal-burning power plants. Oxygen radicals, in turn, damage the mitochondria and the surrounding cell. When sufficient oxidative damage accumulates in the mitochondria and the cell, the cell dies. Hence, the chronic level of mitochondrial oxidative stress is believed to help determine an individuals aging rate and susceptibility to a variety of diseases such as cardiovascular disease, stroke, diabetes, memory loss, forms of deafness and vision loss.

- Study results appear on the online version of Molecular Pharmacology

UC Irvine School of Medicine

Subscribe to Stroke Newsletter
E-mail Address:


About the Center for Molecular and Mitochondrial Medicine and Genetics
The Center for Molecular and Mitochondrial Medicine and Genetics (MAMMAG), under the direction of Douglas C. Wallace, brings together basic scientists, clinical investigators and patients at UCI to determine the causes of the common degenerative diseases, cancer and aging with special emphasis on the role of mitochondria in these processes. The result is a uniquely integrated, multidisciplinary research and clinical program that intends to expand the human horizons of medical understanding. For more information, call (949) 824-3490, or e-mail at

About the University of California, Irvine: Celebrating 40 years of innovation, the University of California, Irvine is a top-ranked university dedicated to research, scholarship and community service. Founded in 1965, UCI is among the fastest-growing University of California campuses, with more than 24,000 undergraduate and graduate students, and about 1,400 faculty members. The second-largest employer in dynamic Orange County, UCI contributes an annual economic impact of $3 billion.

Related Stroke News

New Effort to Treat Stroke More Effectively
REGARDS Study: Stroke Symptoms Common Among General Population
Video game for stroke rehabilitation?
Internal body clock dictates timing of different types of stroke
Stroke Costs in US set to top $2 trillion dollars
Agratroban May Promote Opening Of Arteries Following Stroke
SPARCL Trial: Atorvastatin reduces recurrent stroke risk
Healthy Lifestyle Reduces Women's Stroke Risk
Wingspan Intra-Cranial Stent, Alternative to Brain Surgery?
Blood pressure variability increases risk for stroke death

For any corrections of factual information, to contact the editors or to send any medical news or health news press releases, use feedback form

Top of Page


© Copyright 2004 onwards by RxPG Medical Solutions Private Limited
Contact Us