Featured Research

from universities, journals, and other organizations

Why fish is better than supplements: Omega-3s from fish vs. fish oil pills better at maintaining blood pressure in mouse model

Date:
March 5, 2013
Source:
University of Pennsylvania School of Medicine
Summary:
Researchers show how fish oils help lower blood pressure via vasodilation at ion channels. In vascular smooth muscle cells, such as those that line blood vessels, ion channels that span the outer membrane of a cell to let such ions as sodium, calcium, and potassium in and out, are critical to maintaining proper vessel pressure.

Graphic representation of a potassium transmembrane ion channel.
Credit: Toshinori Hoshi, PhD. Perelman School of Medicine, University of Pennsylvania

Omega-3 fatty acids found in oily fish may have diverse health-promoting effects, potentially protecting the immune, nervous, and cardiovascular systems.

Related Articles


But how the health effects of one such fatty acid -- docosahexaenoic acid (DHA) -- works remains unclear, in part because its molecular signaling pathways are only now being understood.

Toshinori Hoshi, PhD, professor of Physiology, at the Perelman School of Medicine, University of Pennsylvania, and colleagues showed, in two papers out this week in the Proceedings of the National Academy of Sciences, how fish oils help lower blood pressure via vasodilation at ion channels. In vascular smooth muscle cells, such as those that line blood vessels, ion channels that span the outer membrane of a cell to let such ions as sodium, calcium, and potassium in and out, are critical to maintaining proper vessel pressure.

The researchers found that DHA rapidly and reversibly activates these channels by increasing currents by up to 20 fold. DHA lowers blood pressure in anesthetized wild type mice but not in mice genetically engineered without a specific ion channel subunit.

In comparison, the team found that a dietary supplement, DHA ethyl ester, found in most fish oil pills fails to activate the same channels, and even antagonizes the positive effect of DHA from natural sources, on the cells. The DHA ethyl ester seems to compete with the natural form of DHA for binding sites on the ion channel.

The team concluded that these channels have receptors for long-chain omega-3 fatty acids, and that DHA -- unlike its ethyl ester cousin -- activate the channels and lower blood pressure.

The findings have practical implications for the use of omega-3 fatty acids as nutraceuticals for the general public and also for critically ill patients who may receive omega-3-enriched formulas as part of their nutrition.

Coauthor Michael Bauer from Jena University Hospital in Germany, who studies sepsis in a clinical setting, says the findings may encourage physicians to have a closer look at the specific formulations given to sepsis patients as they may contain either the free omega-3 acid or the ester.

The findings also underscore the importance of obtaining omega-3 fatty acids from natural food sources such as oily fish.

The study was supported, in part, by the National Institutes of Health (R01GM057654), the German Research Foundation, and Natural Science Foundation of China.


Story Source:

The above story is based on materials provided by University of Pennsylvania School of Medicine. Note: Materials may be edited for content and length.


Journal References:

  1. T. Hoshi, B. Wissuwa, Y. Tian, N. Tajima, R. Xu, M. Bauer, S. H. Heinemann, S. Hou. Omega-3 fatty acids lower blood pressure by directly activating large-conductance Ca2 -dependent K channels. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1221997110
  2. T. Hoshi, Y. Tian, R. Xu, S. H. Heinemann, S. Hou. Mechanism of the modulation of BK potassium channel complexes with different auxiliary subunit compositions by the omega-3 fatty acid DHA. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1222003110

Cite This Page:

University of Pennsylvania School of Medicine. "Why fish is better than supplements: Omega-3s from fish vs. fish oil pills better at maintaining blood pressure in mouse model." ScienceDaily. ScienceDaily, 5 March 2013. <www.sciencedaily.com/releases/2013/03/130305154531.htm>.
University of Pennsylvania School of Medicine. (2013, March 5). Why fish is better than supplements: Omega-3s from fish vs. fish oil pills better at maintaining blood pressure in mouse model. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2013/03/130305154531.htm
University of Pennsylvania School of Medicine. "Why fish is better than supplements: Omega-3s from fish vs. fish oil pills better at maintaining blood pressure in mouse model." ScienceDaily. www.sciencedaily.com/releases/2013/03/130305154531.htm (accessed October 24, 2014).

Share This



More Health & Medicine News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com
Ebola Fears Keep Guinea Hospitals Empty

Ebola Fears Keep Guinea Hospitals Empty

AP (Oct. 23, 2014) Fears of Ebola are keeping doctors and patients alike away from hospitals in the West African nation of Guinea. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Despite Rising Death Toll, Many Survive Ebola

Despite Rising Death Toll, Many Survive Ebola

AP (Oct. 23, 2014) The family of a Dallas nurse infected with Ebola in the US says doctors can no longer detect the virus in her. Despite the mounting death toll in West Africa, there are survivors there too. (Oct. 23) Video provided by AP
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:

More Coverage


Why Fish Is So Good for You

Mar. 5, 2013 Scientists have decoded the antihypertensive impact of omega-3 fatty acids. They analyzed the impact of omega-3 fatty acids at a systemic level and they also described the underlying molecular ... read more

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