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.

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 July 31, 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 July 31, 2014).

Share This




More Health & Medicine News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Dangerous Bacteria Kills One in Florida

Dangerous Bacteria Kills One in Florida

AP (July 31, 2014) — Sarasota County, Florida health officials have issued a warning against eating raw oysters and exposing open wounds to coastal and inland waters after a dangerous bacteria killed one person and made another sick. (July 31) Video provided by AP
Powered by NewsLook.com
Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) — Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Peace Corps Pulls Workers From W. Africa Over Ebola Fears

Peace Corps Pulls Workers From W. Africa Over Ebola Fears

Newsy (July 30, 2014) — The Peace Corps is one of several U.S.-based organizations to pull workers out of West Africa because of the Ebola outbreak. Video provided by Newsy
Powered by NewsLook.com
Weather Kills 2K A Year, But Storms Aren't The Main Offender

Weather Kills 2K A Year, But Storms Aren't The Main Offender

Newsy (July 30, 2014) — Health officials say 2,000 deaths occur each year in the U.S. due to weather, but it's excessive heat and cold that claim the most lives. Video provided by Newsy
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