Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New clues to healing arthritis caused by traumatic injury

A strain of laboratory mice that has "superhealing" powers has been found to resist inflammation after a knee injury, and also to avoid developing arthritis at the injury site in the long term, according to researchers at Duke University Medical Center.

Their findings illuminate the mechanisms of post-traumatic arthritis and could point to therapies for this condition, which commonly afflicts younger people who lose productivity during their prime working years.

"After a patient's traumatic injury, orthopaedic surgeons realign the joint surface as anatomically as possible and then hope for the best," said Steven A. Olson, MD, FACS, principal investigator of the post-traumatic arthritis project and chief of the Duke orthopaedic trauma section. "They haven't been thinking about why patients with injuries are subsequently getting arthritis. Our research examines how we could possibly prevent arthritis development with growth factors and anti-inflammatory therapies after a fracture, either before or at the time of the surgery to fix it."

Olson said 10 percent of all arthritis cases - about 4.6 million - are post-traumatic arthritis patients, many of whom suffer for years and are too young for joint replacement surgeries. The economic cost thus is about $12.8 billion annually for this group, according to Arthritis Foundation statistics.

The scientists examined the differences in inflammatory response between two types of mice: one type known as superhealers (or MRL/MpJ) versus a strain of control mice (C57BL/6).

Previously, scientists discovered that the superhealer mice had such regenerative powers that holes made in their ears for lab identification purposes grew over completely with no sign of scar tissue. Earlier work done at Duke showed no differences between healthy and fractured limbs when the superhealers healed from a fracture of the knee joint.

"The superhealer can almost regenerate tissue," said Bridgette Furman, research analyst and lead scientist of this study. "We thought, 'if they can regenerate cartilage in the ear, what about cartilage in the knee?' This happened in our pilot study, and we now have taken these results further and learned what happens in terms of inflammation. If you can figure out why the animal is a superhealer and apply that to people, then you may help prevent the development of arthritis."

In the latest experiment, the team got very clear results in the genetic response within injured tissue: the control mice showed a greater than 700-fold increase in the expression of one cytokine, interleukin(IL-1â) in the first four hours after a fracture and 37-fold difference in that cytokine level at 7 days after the fracture. Cytokines are signaling molecules produced by cells in response to injury. Interleukin generally promotes inflammation and an increase in temperature. The superhealer mice showed a similar trend, but in much lower amounts: a 70-fold peak in expression at day 0 down to a 3.5-fold increase by day 7.

A second cytokine, TNF-á, was also expressed at a significantly higher rate in the control mice after the fracture (from a 13-fold peak just after fracture to 5-fold at 7 days), while the superhealer mice showed no change in their levels of TNF-á at all over time.

"Current treatments on the market for rheumatoid arthritist include anakinra (Kineret®, an IL-1 receptor antagonist) and etanercept (Enbrel®, a tumor necrosis factor blocker)," said Farshid Guilak, Ph.D., study scientist and director of the Orthopaedic Bioengineering Laboratory in the Duke Department of Surgery. "In future studies, we plan to use these rheumatoid arthritis drugs right after a fracture to inhibit inflammatory cytokines in the normal mice. If a reduced inflammatory response is what helps the superhealers, we would like to know whether controlling inflammation in fracture patients can prevent arthritis."

The team also studied the mice's joint fluid and blood serum to measure actual levels of the cytokines. Overall, the control mice again showed significantly higher serum levels and synovial (joint) fluid levels of cytokines compared with the superhealers.

The study was presented at the Orthopaedic Research Society meeting, which began on Feb. 22.

Mary Jane Gore | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht NIH scientists describe potential antibody treatment for multidrug-resistant K. pneumoniae
14.03.2018 | NIH/National Institute of Allergy and Infectious Diseases

nachricht Researchers identify key step in viral replication
13.03.2018 | University of Pittsburgh Schools of the Health Sciences

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

Im Focus: Radar for navigation support from autonomous flying drones

At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.

Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

International Virtual Reality Conference “IEEE VR 2018” comes to Reutlingen, Germany

08.03.2018 | Event News

Latest News

Wandering greenhouse gas

16.03.2018 | Earth Sciences

'Frequency combs' ID chemicals within the mid-infrared spectral region

16.03.2018 | Physics and Astronomy

Biologists unravel another mystery of what makes DNA go 'loopy'

16.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>