Featured Research

from universities, journals, and other organizations

Muscle loss in elderly linked to blood vessels' failure to dilate

Date:
May 20, 2010
Source:
University of Texas Medical Branch at Galveston
Summary:
Researchers have found that muscle loss in the elderly is directly linked to decreased post-meal expansion in blood vessels that supply nutrients to muscles.

Why do people become physically weaker as they age? And is there any way to slow, stop, or even reverse this process, breaking the link between increasing age and frailty?

Related Articles


In a paper published online May 19 in the Journal of Clinical Endocrinology & Metabolism, University of Texas Medical Branch at Galveston researchers present evidence that answers to both those questions can be found in the way the network of blood vessels that threads through muscles responds to the hormone insulin.

Normally, these tiny tubes are closed, but when a young person eats a meal and insulin is released into the bloodstream, they open wide to allow nutrients to reach muscle cells. In elderly people, however, insulin has no such "vasodilating" effect.

"We were unsure as to whether decreased vasodilation was just one of the side effects of aging or was one of the main causes of the reduction in muscle protein synthesis in elderly people, because when nutrients and insulin get into muscle fibers, they also turn on lots of intracellular signals linked to muscle growth," said UTMB's Dr. Elena Volpi, senior author of the paper. "This research really demonstrates that vasodilation is a necessary mechanism for insulin to stimulate muscle protein synthesis."

Volpi and her collaborators reached this conclusion after an experiment in which they infused an amount of insulin equivalent to that generated by the body in response to a single meal into the thigh muscles of two sets of young volunteers. One group had been given a drug that blocked vasodilation, while the other was allowed to respond normally. Measurements of muscle protein synthesis levels where made using chemical tracers, while biopsies yielded data on specific biochemical pathways linked to muscle growth.

"We found that by blocking vasodilation, we reproduced in young people the entire response that we see in older persons -- a blunting of muscle protein response and a lack of net muscle growth. In other words, from a muscle standpoint, we made young people look 50 years older," Volpi said.

Such results point the way to what could be a powerful new therapy for age-related frailty and the health and quality-of-life problems that come with it.

"Eventually, if we can improve muscle growth in response to feeding in old people by improving blood flow, then we're going to have a major tool to reduce muscle loss with aging, which by itself is associated with reduction in physical functioning and increased risk of disability," Volpi said.

Other authors of the paper were lead author and postdoctoral fellow Kyle Timmerman, medical student Jessica Lee, assistant professor Hans Dreyer, research scientist Shaheen Dhanani, graduate students Erin Glynn and Christopher Fry, assistant professor Micah Drummond, associate professor Melinda Sheffield Moore, and professor Blake Rasmussen. Specialized metabolic studies were conducted by the staff of the UTMB Clinical Research Center, part of the university's Institute for Translational Sciences. The National Institute on Aging, the UTMB Claude D. Pepper Center Older Americans Independence Center, the National Institute of Child Health and Human Development and the UTMB Clinical Translational Sciences Award supported this study.


Story Source:

The above story is based on materials provided by University of Texas Medical Branch at Galveston. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kyle L. Timmerman, Jessica L. Lee, Hans C. Dreyer, Shaheen Dhanani, Erin L. Glynn, Christopher S. Fry, Micah J. Drummond, Melinda Sheffield-Moore, Blake B. Rasmussen, and Elena Volpi. Insulin Stimulates Human Skeletal Muscle Protein Synthesis via an Indirect Mechanism Involving Endothelial-Dependent Vasodilation and Mammalian Target of Rapamycin Complex 1 Signaling. Journal of Clinical Endocrinology & Metabolism,, May 19, 2010 DOI: 10.1210/jc.2009-2696

Cite This Page:

University of Texas Medical Branch at Galveston. "Muscle loss in elderly linked to blood vessels' failure to dilate." ScienceDaily. ScienceDaily, 20 May 2010. <www.sciencedaily.com/releases/2010/05/100519163846.htm>.
University of Texas Medical Branch at Galveston. (2010, May 20). Muscle loss in elderly linked to blood vessels' failure to dilate. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2010/05/100519163846.htm
University of Texas Medical Branch at Galveston. "Muscle loss in elderly linked to blood vessels' failure to dilate." ScienceDaily. www.sciencedaily.com/releases/2010/05/100519163846.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) — The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Newsy (Nov. 25, 2014) — Need another reason to eat yogurt every day? Researchers now say it could reduce a person's risk of developing type 2 diabetes. Video provided by Newsy
Powered by NewsLook.com
Madagascar Working to Contain Plague Outbreak

Madagascar Working to Contain Plague Outbreak

AFP (Nov. 24, 2014) — Madagascar said Monday it is trying to contain an outbreak of plague -- similar to the Black Death that swept Medieval Europe -- that has killed 40 people and is spreading to the capital Antananarivo. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Are Female Bosses More Likely To Be Depressed?

Are Female Bosses More Likely To Be Depressed?

Newsy (Nov. 24, 2014) — A new study links greater authority with increased depressive symptoms among women in the workplace. 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:

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