Featured Research

from universities, journals, and other organizations

Aging, obsolete cells prime the lungs for pneumonia

Date:
May 27, 2011
Source:
University of Texas Health Science Center at San Antonio
Summary:
Why are older people vulnerable to community-acquired pneumonia? A new study gives an explanation: cells that are supposed to die, but don't.

Community-acquired pneumonia is the leading cause of infectious death among the elderly. Newly published research from The University of Texas Health Science Center San Antonio suggests why older people are vulnerable and offers a possible defense.

The researchers found that when it comes to aging and pneumonia, one bad apple can ruin the barrel. Lung cells that were supposed to die due to DNA damage -- but didn't -- were 5 to 15 times more susceptible to invasion by pneumonia-causing bacteria. These bad apples also increased the susceptibility of normal cells around them. The research was published on May 25 in the journal Aging Cell.

Close to 1 billion adults worldwide are at risk for pneumonia. They include more than 800 million adults who are older than 65 and an estimated 210 million with chronic obstructive pulmonary disease (COPD).

Injurious effects

Both age and COPD are associated with senescent cells, which are unable to die due to dysregulated function. These cells have increased levels of proteins that disease-causing bacteria stick to and co-opt to invade the bloodstream. The cells also spew out molecules that increase inflammation, and make normal cells nearby do the same.

"Senescent cells prime the lungs for infection," said Pooja Shivshankar, Ph.D., research scientist in microbiology and immunology at the UT Health Science Center and first author on the study.

Controlling the inflammatory molecules' release could short-circuit pneumonia risk in the elderly, said the senior author, Carlos Orihuela, Ph.D., assistant professor of microbiology and immunology, also at the Health Science Center.

"We can't stop aging, but our findings suggest that preventing inflammation might be the next best thing," Dr. Orihuela said. "This opens up possibilities for anti-inflammatory drugs as treatments for pneumonia."

Mouse study

The scientists compared aged and young mice, all healthy. The older mice were found to have increased lung inflammation with higher levels of senescence markers; this was consistent with previous studies in the literature.

The lung cells in aged mice also proved to be more susceptible to infection by Streptococcus pneumonia, the bacterium that causes pneumonia. This was determined by increased levels of proteins to which the bacteria adhere and by testing bacterial adhesion to the lung cells.

Four different experiments -- on senescent cells, on normal lung cells exposed to senescent cells, on aged mice and on young mice exposed to gene-damaging stress -- revealed increased susceptibility to pneumonia infection.

"This potentially helps to explain why the elderly and individuals with COPD are predisposed to community-acquired pneumonia," Dr. Orihuela said.

The scientists are in the Graduate School of Biomedical Sciences, the School of Medicine, and the Sam and Ann Barshop Institute for Longevity and Aging Studies at the UT Health Science Center San Antonio.


Story Source:

The above story is based on materials provided by University of Texas Health Science Center at San Antonio. Note: Materials may be edited for content and length.


Journal Reference:

  1. Pooja Shivshankar, Angela Rodriguez Boyd, Claude Jourdan Le Saux, I-Tien Yeh, Carlos J. Orihuela. Cellular senescence increases expression of bacterial ligands in the lungs and is positively correlated with increased susceptibility to pneumococcal pneumonia. Aging Cell, 2011; DOI: 10.1111/j.1474-9726.2011.00720.x

Cite This Page:

University of Texas Health Science Center at San Antonio. "Aging, obsolete cells prime the lungs for pneumonia." ScienceDaily. ScienceDaily, 27 May 2011. <www.sciencedaily.com/releases/2011/05/110526131242.htm>.
University of Texas Health Science Center at San Antonio. (2011, May 27). Aging, obsolete cells prime the lungs for pneumonia. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2011/05/110526131242.htm
University of Texas Health Science Center at San Antonio. "Aging, obsolete cells prime the lungs for pneumonia." ScienceDaily. www.sciencedaily.com/releases/2011/05/110526131242.htm (accessed July 23, 2014).

Share This




More Health & Medicine News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Courts Conflicted Over Healthcare Law

Courts Conflicted Over Healthcare Law

AP (July 22, 2014) Two federal appeals courts issued conflicting rulings Tuesday on the legality of the federally-run healthcare exchange that operates in 36 states. (July 22) Video provided by AP
Powered by NewsLook.com
Why Do People Believe We Only Use 10 Percent Of Our Brains?

Why Do People Believe We Only Use 10 Percent Of Our Brains?

Newsy (July 22, 2014) The new sci-fi thriller "Lucy" is making people question whether we really use all our brainpower. But, as scientists have insisted for years, we do. Video provided by Newsy
Powered by NewsLook.com
Scientists Find New Way To Make Human Platelets

Scientists Find New Way To Make Human Platelets

Newsy (July 22, 2014) Boston scientists have discovered a new way to create fully functioning human platelets using a bioreactor and human stem cells. Video provided by Newsy
Powered by NewsLook.com
Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

TheStreet (July 21, 2014) New research shows Gilead Science's drug Sovaldi helps in curing hepatitis C in those who suffer from HIV. In a medical study, the combination of Gilead's Hep C drug with anti-viral drug Ribavirin cured 76% of HIV-positive patients suffering from the most common hepatitis C strain. Hepatitis C and related complications have been a top cause of death in HIV-positive patients. Typical medication used to treat the disease, including interferon proteins, tended to react badly with HIV drugs. However, Sovaldi's %1,000-a-pill price tag could limit the number of patients able to access the treatment. TheStreet's Keris Lahiff reports from New York. Video provided by TheStreet
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