Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Estrogens as antioxidants - reducing heart disease in younger postmenopausal women

07.07.2003


HRT could be used to protect younger postmenopausal women from heart disease. An article published in the journal Lipids in Health and Disease shows that estrogens commonly used in HRT reduce the build up of harmful oxidised lipoproteins, which can lead to heart disease, by acting as antioxidants.



It is well known that high-density lipoproteins (HDL) protect against heart disease while low-density lipoproteins (LDL) promote it. However, recent research has shown that the relationship is not that simple. The effectiveness of both types of lipoprotein change when they are oxidised by free radicals – highly reactive by-products of metabolism. If LDL becomes oxidised its ability to cause heart disease increases. If HDL becomes oxidised its ability to protect against heart disease is lessened.

Researchers from St. Michael’s Hospital, part of the University of Toronto, have shown that estrogens can act as antioxidants, which neutralise free radicals, and hence protect HDL from oxidation. In addition, high levels of HDL are able to protect LDL from oxidation, and this ability is strongly enhanced when estrogens are present.


Dr Bhagu Bhavnani’s team, who carried out the research, write, “The inhibition of HDL oxidation and the enhancement provided by estrogens toward the inhibition of LDL oxidation may be another way in which estrogens reduce the risk of coronary heart disease in healthy young postmenopausal women.”

Although recent randomised control trials have shown that HRT in older women may not reduce the incidence of coronary heart disease, Dr. Bhavnani believes that this is not the whole story. Although his team carried out experiments in test tubes rather than in human subjects they saw that estrogen had beneficial effects at concentrations lower than those found in women on HRT. He urges that, “randomised control trials using lower doses of HRT, different estrogens and progestins, and in younger postmenopausal women, from 50 to 60 years, are urgently needed to resolve the confusion created by recent studies”.

The research team used blood taken from men and postmenopausal women to carry out experiments in vitro. They measured the resistance of HDL to oxidation in the presence or absence of increasing concentrations of eleven different estrogens. All of these estrogens are components of a combined estrogen supplement that is commonly used for HRT by postmenopausal women. They then assessed whether the presence of HDL increased the resistance of LDL to oxidation, and if this resistance was further enhanced by the addition of estrogen.

They found that all the estrogens tested were able to protect HDL from oxidation and to enhance HDL’s ability to protect LDL from oxidation. They also found that different estrogens had different potencies as antioxidants, with an estrogen called Equilenin being the most effective.

According to recent data from the British Heart Foundation, women are five times less likely to suffer from coronary heart disease than men. This reduced risk can only partly be explained by differences in behaviour, such as smoking or stress levels. As women’s risk of heart disease increases after menopause it has been suggested that ovarian hormones such as estrogen play a role in protecting younger women from the disease. The research from Bhavnani’s team supports this idea.

Gemma Bradley | BioMed Central
Further information:
http://www.biomedcentral.com
http://www.lipidworld.com/content/2/1/4

More articles from Health and Medicine:

nachricht New leukemia treatment offers hope
23.09.2016 | King Abdullah University of Science and Technology

nachricht Alzheimer’s: Cellular Mechanism Provides Explanation Model for Declining Memory Performance
21.09.2016 | Deutsches Zentrum für Neurodegenerative Erkrankungen e.V. (DZNE)

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: OLED microdisplays in data glasses for improved human-machine interaction

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.

“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...

Im Focus: Artificial Intelligence Helps in the Discovery of New Materials

With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.

Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...

Im Focus: Complex hardmetal tools out of the 3D printer

For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.

Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...

Im Focus: Launch of New Industry Working Group for Process Control in Laser Material Processing

At AKL’16, the International Laser Technology Congress held in May this year, interest in the topic of process control was greater than expected. Appropriately, the event was also used to launch the Industry Working Group for Process Control in Laser Material Processing. The group provides a forum for representatives from industry and research to initiate pre-competitive projects and discuss issues such as standards, potential cost savings and feasibility.

In the age of industry 4.0, laser technology is firmly established within manufacturing. A wide variety of laser techniques – from USP ablation and additive...

Im Focus: New laser joining technologies at ‘K 2016’ trade fair

Every three years, the plastics industry gathers at K, the international trade fair for plastics and rubber in Düsseldorf. The Fraunhofer Institute for Laser Technology ILT will also be attending again and presenting many innovative technologies, such as for joining plastics and metals using ultrashort pulse lasers. From October 19 to 26, you can find the Fraunhofer ILT at the joint Fraunhofer booth SC01 in Hall 7.

K is the world’s largest trade fair for the plastics and rubber industry. As in previous years, the organizers are expecting 3,000 exhibitors and more than...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Experts from industry and academia discuss the future mobile telecommunications standard 5G

23.09.2016 | Event News

ICPE in Graz for the seventh time

20.09.2016 | Event News

Using mathematical models to understand our brain

16.09.2016 | Event News

 
Latest News

Chains of nanogold – forged with atomic precision

23.09.2016 | Life Sciences

New leukemia treatment offers hope

23.09.2016 | Health and Medicine

Self-assembled nanostructures hit their target

23.09.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>