Featured Research

from universities, journals, and other organizations

Delayed Healing Associated With Smoking In Mice

Date:
November 10, 2006
Source:
John Wiley & Sons, Inc.
Summary:
Two new studies, funded by the National Institutes of Health and the National Football League Charities, examined the effects of smoking on fractures and ligament healing in mice and found that healing of both types of injury was delayed.

Cigarette smoking, which causes over 8.6 million illnesses annually in the U.S., has been shown to have harmful effects on a variety of orthopedic conditions. Studies have shown that the numerous toxins contained in cigarette smoke can undermine fracture and ligament repair following injury. In addition, smokers have higher rates of hip fracture, fracture healing problems and bone infections and smoking has been shown to impair soft tissue wound healing.

Two new studies, funded by the National Institutes of Health and the National Football League Charities, examined the effects of smoking on fractures and ligament healing in mice and found that healing of both types of injury was delayed. The studies are published in the December 2006 issue of the Journal of Orthopaedic Research, the official journal of the Orthopaedic Research Society.

Led by Hossam B. El-Zawawy of the Washington University School of Medicine in St. Louis, MO the first study involved 35 mice divided into a smoking group, which was exposed to cigarette smoke 6 days per week for a month, and a control group. Surgery was performed on all the mice to achieve a simple fracture. Researchers used type II collagen expression as a marker of cartilage formation (chondrogenesis) during healing. They found that smoking delayed fracture healing and that it began at the early stages of the healing process, although over time it did not inhibit normal healing. Specifically, they were able to show that there was a delay in the development of mature cartilage cells in the mice exposed to cigarette smoke. This was the first study to analyze the molecular and cellular mechanisms of fracture healing in mice exposed to smoke.

The authors note that while the study shows a clear relationship between smoking and cartilage formation, smoking probably has other effects on fracture healing, which should be addressed in future studies. They conclude: "Clinically, if specific events can be identified, smoking cessation in humans, even temporarily, may improve or speed the healing process after injury and decrease the significant morbidity associated with cigarette smoking during fracture healing."

In the second study, involving the same group of researchers but led by Corey S. Gill, researchers examined the effects of smoking on medial collateral ligament (MCL) injury. They performed MCL surgery on 40 mice, half of which were exposed to cigarette smoke 6 days a week for two months. Researchers quantified cellular density at the site of injury and used Type I collagen gene expression as a marker for the formation of extracellular matrix, the material outside of cells that provides tissue support. The results showed for the first time that cellular density in mice increased between 3 and 7 days after injury in normal wound healing, and that this was partially inhibited in mice exposed to cigarette smoke. Based on their findings, the authors suggest that this delay is due to a difference in the recruitment of cells to the site of injury.

In addition, the study found that mice exposed to smoke had impaired or delayed extracellular matrix development, shown by lower collagen type I gene expression, one week after injury. This may lead to a delay in restoring biomechanical stability of the healing MCL. The authors conclude: "Ultimately, a better understanding of the cellular and molecular mechanisms involved in the MCL healing process will allow physicians to improve or speed the healing process, as well as potentially overcome the deleterious effects of smoking on ligament healing."

Articles:

"Smoking Delays Chondrogenesis in a Mouse Model of Closed Tibial Fracture Healing," Hossam B. El-Zawawy, Corey S. Gill, Rick W. Wright, Linda J. Sandell, Journal of Orthopaedic Research, December 2006; (DOI: 10.1002/jor.20263).

"Effects of Cigarette Smoking on Early Medial Collateral Ligament Healing in a Mouse Model," Corey S. Gill, Linda J. Sandell, Hossam B. El-Zawawy, Rick W. Wright, Journal of Orthopaedic Research, December 2006; (DOI: 10.1002/jor.20234).


Story Source:

The above story is based on materials provided by John Wiley & Sons, Inc.. Note: Materials may be edited for content and length.


Cite This Page:

John Wiley & Sons, Inc.. "Delayed Healing Associated With Smoking In Mice." ScienceDaily. ScienceDaily, 10 November 2006. <www.sciencedaily.com/releases/2006/11/061106144721.htm>.
John Wiley & Sons, Inc.. (2006, November 10). Delayed Healing Associated With Smoking In Mice. ScienceDaily. Retrieved April 23, 2014 from www.sciencedaily.com/releases/2006/11/061106144721.htm
John Wiley & Sons, Inc.. "Delayed Healing Associated With Smoking In Mice." ScienceDaily. www.sciencedaily.com/releases/2006/11/061106144721.htm (accessed April 23, 2014).

Share This



More Health & Medicine News

Wednesday, April 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Big Pharma Braces for M&A Wave

Big Pharma Braces for M&A Wave

Reuters - Business Video Online (Apr. 22, 2014) Big pharma on the move as Novartis boss, Joe Jimenez, tells Reuters about plans to transform his company via an asset exchange with GSK, and Astra Zeneca shares surge on speculation that Pfizer is looking for a takeover. Joanna Partridge reports. Video provided by Reuters
Powered by NewsLook.com
Study Says Most Crime Not Linked To Mental Illness

Study Says Most Crime Not Linked To Mental Illness

Newsy (Apr. 22, 2014) A new study finds most crimes committed by people with mental illness are not caused by symptoms of their illness or disorder. Video provided by Newsy
Powered by NewsLook.com
Hagel Gets Preview of New High-Tech Projects

Hagel Gets Preview of New High-Tech Projects

AP (Apr. 22, 2014) Defense Secretary Chuck Hagel is given hands-on demonstrations Tuesday of some of the newest research from DARPA _ the military's Defense Advanced Research Projects Agency program. (April 22) Video provided by AP
Powered by NewsLook.com
How Smaller Plates And Cutlery Could Make You Feel Fuller

How Smaller Plates And Cutlery Could Make You Feel Fuller

Newsy (Apr. 22, 2014) NBC's "Today" conducted an experiment to see if changing the size of plates and utensils affects the amount individuals eat. 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