Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Antibiotics protect nerves in mice by turning on genes

06.01.2005


Large, multi-center clinical trial planned in Lou Gehrig’s disease



A family of antibiotics that includes penicillin may help prevent nerve damage and death in a wide variety of neurological diseases, including Lou Gehrig’s disease, dementia, stroke, and epilepsy, Johns Hopkins researchers have found. The antibiotics’ beneficial effects, discovered in experiments in the lab and with mice, are unrelated to their ability to kill bacteria, the researchers report in the Jan. 6 issue of Nature. Instead, the drugs squelch the dangerous side of a brain chemical called glutamate by turning on at least one gene, thereby increasing the number of "highways," or transporters, that remove glutamate from nerves.

"It would be extremely premature for patients to ask for or take antibiotics on their own," says the study’s leader, Jeffrey Rothstein, M.D., Ph.D., director of the Robert Packard Center for ALS Research at Johns Hopkins and a professor of neurology and of neuroscience. "Only a clinical trial can prove whether one of these antibiotics can help and is safe if taken for a long time."


In mice engineered to develop the equivalent of Lou Gehrig’s disease, daily injections of an antibiotic called ceftriaxone, started just as symptoms tend to surface, delayed both nerve damage and symptoms and extended survival by 10 days compared to untreated animals. Lou Gehrig’s disease, or amyotrophic lateral sclerosis (ALS), in people causes progressive weakness and paralysis and ends in death, usually within three to five years of diagnosis. "We’re very excited by these drugs’ abilities," says Rothstein. "They show for the first time that drugs, not just genetic engineering, can increase numbers of specific transporters in brain cells. Because we study ALS, we tested the drugs in a mouse model of that disease, but this is much bigger than ALS. This approach has potential applications in numerous neurologic and psychiatric conditions that arise from abnormal control of glutamate."

A large, multi-center clinical trial planned for the spring will help determine the best dose of and schedule for ceftriaxone in people with ALS, and will measure whether the known risks of long-term antibiotic treatment are worth it, he says. The drug is currently approved by the U.S. Food and Drug Administration and used to treat bacterial infections in the brain.

More than a dozen of penicillin’s relatives, known as beta-lactam antibiotics, were among protective agents identified by a National Institutes of Health-funded project to screen 1,040 Food and Drug Administration-approved drugs for new uses. The newfound ability of these antibiotics to activate glutamate transporters and to protect nerves, and the drugs’ potential therapeutic use in neurological conditions, are covered by patent applications held by Rothstein and Johns Hopkins and licensed to Ruxton Pharmaceuticals Inc.

Of the antibiotics, penicillin protected nerve cells best in laboratory dishes, but ceftriaxone had the best results in mice, probably because it more easily crosses into the brain from the blood, the researchers report.

Rothstein and his colleagues determined that the antibiotics’ benefit stems from their newly recognized effect on glutamate’s Jekyll-and-Hyde effects. In the brain, glutamate normally excites nerves so that electrical signals can travel from one to the next. But too much of the chemical can overstimulate and kill nerves, a factor in ALS and some other diseases.

In a series of experiments, the researchers discovered that the antibiotics activate the gene encoding glutamate’s main transporter in brain cells. Rats and mice that received daily ceftriaxone for up to a week had triple the usual amount of the transporter, known as GLT1, in their brain cells, an effect that lasted for up to three months after treatment. "Glutamate is just one of many messengers brain cells use to communicate with one another, and this is just one of the transporters that move glutamate," says Rothstein. "So if you can find the right drug, you might be able to specifically affect other transporters, too."

Because ceftriaxone only protects against glutamate damage, just one problem in ALS, it’s not surprising that the mice eventually succumbed to weakness and paralysis despite treatment, he says. "If we can find drugs that protect against other causes of nerve death in ALS, the combination might offer a real therapy, much like using drug combinations to treat cancer," says Rothstein. "The more we know about ALS and other neurological diseases, the better our chances of finding ways to prevent nerve death by all causes."

The research was funded by the National Institute of Neurological Disorders and Stroke, the Muscular Dystrophy Association and the Robert Packard Center for ALS Research at Johns Hopkins. The ALS mice were provided by Project ALS.

Authors of the paper are Rothstein, Sarubhai Patel, Melissa Regan, Christine Haenggeli, Yanhua Huang, Dwight Bergles, Lin Jin, Margaret Dykes Hoberg, Svetlana Vidensky, Dorothy Chung and Shuy Vang Toan, all of Johns Hopkins; Lucie Bruijn of The ALS Association; and Zao-zhong Su, Pankaj Gupta and Paul Fisher of Columbia University Medical Center.

Joanna Downer | EurekAlert!
Further information:
http://www.jhmi.edu
http://www.nature.com/nature

More articles from Life Sciences:

nachricht Bare bones: Making bones transparent
27.04.2017 | California Institute of Technology

nachricht Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel

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

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

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Bare bones: Making bones transparent

27.04.2017 | Life Sciences

Study offers new theoretical approach to describing non-equilibrium phase transitions

27.04.2017 | Physics and Astronomy

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>