Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Switch in cell's 'power plant' declines with age, rejuvenated by drug

17.08.2011
Researchers at the Johns Hopkins University School of Medicine have found a protein normally involved in blood pressure regulation in a surprising place: tucked within the little "power plants" of cells, the mitochondria.

The quantity of this protein appears to decrease with age, but treating older mice with the blood pressure medication losartan can increase protein numbers to youthful levels, decreasing both blood pressure and cellular energy usage.

The researchers say these findings, published online during the week of August 15, 2011, in the Proceedings of the National Academy of Sciences, may lead to new treatments for mitochondrial–specific, age-related diseases, such as diabetes, hearing loss, frailty and Parkinson's disease.

"We've identified a functional and independently operated system that appears to influence energy regulation within the mitochondria," explains Jeremy Walston, M.D., professor of geriatric medicine at Hopkins. "This mitochondrial angiotensin system is activated by commonly utilized blood pressure medications, and influences both nitric oxide and energy production when signaled."

Previous research showed that manipulating angiotensin in the body's cells had unexpectedly affected mitochondrial energy production, so Walston and Peter Abadir , M.D., an assistant professor of geriatric medicine, decided to examine the role of angiotensin within the mitochondria. Using high-powered microscopy, they and their collaborators found evidence within the mitochondria of angiotensin as well as one of the protein receptors that bind to and detect it. They also pinpointed the angiotensin receptor's exact locations within the mitochondria of mouse kidney, liver, neuron and heart cells as well as in human white blood cells.

The team then treated mitochondria with a chemical known to activate the angiotensin receptors and measured the cell's response. This resulted in a decrease in oxygen consumption by half and a small increase in nitric oxide production—indicating less energy made by the mitochondria and lowered blood pressure, respectively. Explains Walston, "Activating angiotensin receptors within the mitochondria with these agents led to lowered blood pressure and decreased cellular energy use."

But they found even more than just an energy-regulating mechanism; after testing the angiotensin system in mitochondria of both young and old mice, they noticed a decrease by almost a third of the amount of the angiotensin receptor type 2 in the mitochondria in older mice, meaning that cells in older mice were unable to control energy use as well. The researchers then tried treating these older mice with the blood pressure lowering drug losartan daily for 20 weeks and found that the number of these receptors increased. "Treatment of the old mice with losartan resulted in a marked increase in the number of receptors that are known to positively influence blood pressure and decrease inflammation," says Walston.

Declining mitochondria are known to influence chronic diseases in older adults, explains Walston, whose next step is to translate studies from cell culture and animal based studies to human studies in hopes of developing new therapies. "Our findings will help us determine if the drugs that interact with this receptor will also lead to improvement of mitochondrial function and energy production. This, in turn, could facilitate the treatment of a number of chronic diseases of older adults."

This study was funded by the Johns Hopkins Older Americans Independence Center, the National Institute on Aging and the American Geriatrics Society.

Additional authors on this study from the Division of Geriatric Medicine and Gerontology at Johns Hopkins were Peter Abadir, Alka Jain, and Neal Fedarko.

John Lazarou | EurekAlert!
Further information:
http://www.jhmi.edu

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>