Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Circadian clock may impact organ transplant success

04.10.2011
Health care providers assess blood and tissue type as well as organ size and health to enhance transplant success. New research indicates that checklist might also need to include the circadian clock.

While some human studies have shown the time of day transplant surgery is performed can influence the outcome, this study of mice with dysfunctional internal clocks is the first correlating circadian clocks with transplant success, said Dr. Daniel Rudic, vascular biologist at Georgia Health Sciences University and corresponding author of the study published in Proceedings of the National Academy of Sciences.

The GHSU researchers found that arteries of mice with circadian clock dysfunction became thick and diseased within a few weeks of being transplanted to healthy mice. Arteries transplanted from healthy mice to the mutant mice remained healthy.

Blood vessel disease, and resulting blood loss to donated organs, is a key pitfall for transplant patients, potentially leading to organ failure and rejection.

"You take an organ out of a human, you don't think about it having a bad clock," Rudic said. "But the fact is the time at which you do the organ transplant may influence overall success and, if you have a donor who has a sleep disorder or is a night shift worker, it may affect it as well."

Since even healthy clocks produce variability in tissue function across the span of a day, transplantation might be best performed during optimal organ function, he said.

In addition to enabling sleep/wake cycles, circadian clocks are found throughout the body and involved in a lot more than sleep. "The clock is expressed not only in the brain but everywhere in the body and can function autonomously in different areas," Rudic said.

"Our research shows it's the clock within the blood vessel that is key to conferring the disease response in this case," said Dr. Bo Cheng, GHSU postdoctoral fellow and the study's first author.

While the researchers can determine whether clock gene expression is up, down or mutated, there is currently no way to do the tests in humans. Until screening tests are identified, donors could be screened for signs of dysfunction such as a sleep disorder or even aberrant behaviors that can impair healthy clocks, such as shift work, Rudic said. "Ideally this will open up some new research avenues," he said.

Interestingly, when blood vessels from the mutant mouse stay in that mouse, disease progression is much slower. "We believe that bad clock function worsens when it intersects with disease, so if you are eating a high-fat diet or if you undergoing a serious surgery like a transplant, and you have a bad clock, disease may occur and may occur quickly," Rudic said.

In 2009, he reported in the journal Circulation that mice with mutated or missing clock genes were prone to vascular disease similar to smokers and people with high blood pressure and cholesterol. That study showed the blood vessel clocks regulate key signaling that enables blood vessel dilation and remodeling.

Toni Baker | EurekAlert!
Further information:
http://www.georgiahealth.edu

More articles from Life Sciences:

nachricht Modern genetic sequencing tools give clearer picture of how corals are related
17.08.2017 | University of Washington

nachricht The irresistible fragrance of dying vinegar flies
16.08.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Gold shines through properties of nano biosensors

17.08.2017 | Physics and Astronomy

Greenland ice flow likely to speed up: New data assert glaciers move over sediment, which gets more slippery as it gets wetter

17.08.2017 | Earth Sciences

Mars 2020 mission to use smart methods to seek signs of past life

17.08.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>