Featured Research

from universities, journals, and other organizations

Synthesized compound also found in bear bile chemical could help keep hearts in rhythm

Date:
August 2, 2011
Source:
Imperial College London
Summary:
A synthesized compound which is also found in bear bile could help prevent disturbances in the heart's normal rhythm, according to new research.

A synthesised compound which is also found in bear bile could help prevent disturbances in the heart's normal rhythm, according to research published in the journal Hepatology by a team from Imperial College London.

Related Articles


Ursodeoxycholic acid (UDCA) is manufactured as a drug to decrease production of cholesterol in the body and to dissolve gallstones. It is also present in many traditional Chinese medicines made from bear bile. However, the farming of bears for their bile has been condemned as cruel by animal rights groups, and the use of bear bile products is not encouraged by the study authors.

The new study suggests that UDCA could also potentially treat abnormal heart rhythm or arrhythmia, both in the fetus and in people who have suffered a heart attack. Laboratory tests suggested that UDCA acts on non-beating pathological heart cells called myofibroblasts, which interfere with how electrical signals travel across the heart.

UDCA is already used to treat a condition called obstetric cholestasis, which affects around one in 200 pregnant women in the UK and is linked to a higher risk of arrhythmia and sudden death in the fetus. UDCA lowers the levels of harmful bile acids which build up in the mother's blood in the disease and can pass into the infant through the placenta.

The study demonstrates for the first time that UDCA can prevent arrhythmia by altering the electrical properties of myofibroblasts. These cells are found in the fetal heart but disappear shortly after birth. However, they reappear in patients that have had a heart attack, when they are involved in laying down scar tissue.

The study found that these cells disrupt the transmission of electrical signals that control the heart's rhythm. The study is the result of a long-term collaboration between two Imperial research groups, headed by Dr Juila Gorelik, at the National Heart and Lung Institute and Professor Catherine Williamson at the Institute of Reproductive and Developmental Biology.

"These findings are exciting because the treatments we have now are largely ineffective at preventing arrhythmia in patients who develop an abnormal heart rhythm after a heart attack," said Dr Julia Gorelik, the study's senior author. "Our results from the lab suggest that UDCA could help the heart muscle conduct electrical signals more normally. We're hoping to set up a clinical trial to test whether these results translate to patients with heart failure.

"The medical uses of UDCA are not a reason to take bile from bears. Since UDCA can be synthesised chemically, there is no need to inflict any cruelty on bears and we do not encourage this."

The researchers became interested in the role of myofibroblasts after observing that they appear in the heart tissue in the second and third trimesters of gestation, when sudden death of the infant is most common in pregnancies affected by obstetric cholestasis.

The researchers grew myofibroblasts on top of heart muscle cells in the laboratory to create a model for studying the fetal heart. Then they used a number of specialised microscopic techniques to study how the cells communicate to relay electrical signals.

Exposing the cells to high level of bile acid, as found in the mother's and fetal blood in obstetric cholestasis, caused the cells to conduct electrical signals more slowly and increased the likelihood of arrhythmia. This effect was not seen when there were no myofibroblasts present among the heart muscle cells, as in the healthy adult heart.

When the cells were exposed to bile acids and UDCA, it altered the electrical properties of the myofibroblasts, and the electrical signals propagated across the cell culture more regularly.

"Myofibroblasts affect the propagation of electrical signals that co-ordinate the pumping function of the heart," said Dr Michele Miragoli, first author of the study. "Complications from obstetric cholestasis occur most commonly in the last trimester of pregnancy, when the density of myofibroblasts is highest in the fetal heart.

"Our study suggests that it is the appearance of myofibroblast cells that make the fetus vulnerable to arrhythmia in obstetric cholestasis. We think that targeting these cells could be an important new approach for preventing abnormal heart rhythm, not just in the fetus, but also in people who have had a heart attack."

The study was funded by Action Medical Research, the Wellcome Trust, the Swiss National Science Foundation, and the Imperial Comprehensive Biomedical Research Centre, which was established by a grant from the National Institute of Health Research.


Story Source:

The above story is based on materials provided by Imperial College London. Note: Materials may be edited for content and length.


Journal Reference:

  1. Michele Miragoli, Siti H. Sheikh Abdul Kadir, Mary N. Sheppard, Nicolσ Salvarani, Matilda Virta, Sarah Wells, Max J. Lab, Viacheslav O. Nikolaev, Alexey Moshkov, William M. Hague, Stephan Rohr, Catherine Williamson, Julia Gorelik. A protective antiarrhythmic role of ursodeoxycholic acid in an in vitro rat model of the cholestatic fetal heart. Hepatology, 2011; DOI: 10.1002/hep.24492

Cite This Page:

Imperial College London. "Synthesized compound also found in bear bile chemical could help keep hearts in rhythm." ScienceDaily. ScienceDaily, 2 August 2011. <www.sciencedaily.com/releases/2011/08/110801191215.htm>.
Imperial College London. (2011, August 2). Synthesized compound also found in bear bile chemical could help keep hearts in rhythm. ScienceDaily. Retrieved November 24, 2014 from www.sciencedaily.com/releases/2011/08/110801191215.htm
Imperial College London. "Synthesized compound also found in bear bile chemical could help keep hearts in rhythm." ScienceDaily. www.sciencedaily.com/releases/2011/08/110801191215.htm (accessed November 24, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Monday, November 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Winter Can Cause Depression — Here's How To Combat It

Winter Can Cause Depression — Here's How To Combat It

Newsy (Nov. 23, 2014) — Millions of American suffer from seasonal depression every year. It can lead to adverse health effects, but there are ways to ease symptoms. Video provided by Newsy
Powered by NewsLook.com
Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

AFP (Nov. 23, 2014) — The arable district of Kenema in Sierra Leone -- at the centre of the Ebola outbreak in May -- has been under quarantine for three months as the cocoa harvest comes in. Duration: 01:32 Video provided by AFP
Powered by NewsLook.com
Don't Fall For Flu Shot Myths

Don't Fall For Flu Shot Myths

Newsy (Nov. 23, 2014) — Misconceptions abound when it comes to your annual flu shot. Medical experts say most people older than 6 months should get the shot. Video provided by Newsy
Powered by NewsLook.com
WFP: Ebola Risks Heightened Among Women Throughout Africa

WFP: Ebola Risks Heightened Among Women Throughout Africa

AFP (Nov. 21, 2014) — Having children has always been a frightening prospect in Sierra Leone, the world's most dangerous place to give birth, but Ebola has presented an alarming new threat for expectant mothers. Duration: 00:37 Video provided by AFP
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:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

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