About My Health Careers Internship MedBlogs Contact us
Medindia LOGIN REGISTER
Advertisement

New Drug Combo Kills Antibiotic-resistant Bacteria

by Thilaka Ravi on November 14, 2013 at 2:51 PM
Font : A-A+

New Drug Combo Kills Antibiotic-resistant Bacteria

A drug combination that destroys antibiotic-resistant germs in mice, potentially opening a new front against chronic and relapsing infections in humans was unveiled by scientists.

Big Pharma had been closely interested in a compound dubbed acyldepsipeptide (ADEP), only to drop it when some germs became resistant to it.

Advertisement

But scientists in the United States reported that, when used alongside conventional antibiotics, ADEP proved to be a relentless killer.

"We decided to pair it to conventional antibiotics.... to stem the propagation of (drug) resistant cells," said study co-author Kim Lewis of Northeastern University in Boston.
Advertisement

The combination "completely sterilised" bacteria in a Petri dish and in mice whose thighs had been severely infected, said Lewis.

"Efficacy in an animal model is actually a pretty good predictor of efficacy in humans, so I think it is entirely realistic" that a drug may result, he added.

Humans rely on antibiotics to fight off a vast array of bacterial diseases, from tonsillitis to tuberculosis.

But antibiotics do not work for all types of bacteria, and in some types where they are effective, germs are evolving worryingly into forms that are resistant to the drug.

Some infections are caused by biofilms -- slimy collections of bacterial cells that coat infected areas and block out the immune system, according to a podcast by Nature, accompanying the study in the British journal.

While antibiotics can penetrate those biofilms, they fail to clear up the infection because of so-called "persister cells".

These are hibernating cells within the biofilm that stop dividing or growing and shut down their metabolism.

The dormant cells are the main cause of chronic and relapsing bacterial infections, since conventional antibiotics can target only actively growing bacterial cells.

"We had to look for something that in a persister will activate a function, will corrupt it, force it to kill the cell," said Lewis.

Drug combo triggers cell death

The team tested ADEP in the lab and found it activates a protease in cells -- protease is a protein that breaks up other proteins, eventually causing cell death.

In the experiments, the protease degraded proteins in the bacterial cells, causing these molecules to "self-digest", said Lewis.

"It doesn't matter whether that cell was growing, dormant, persister. So that compound has the ability to sterilise an infection," he said.

The reason that pharmaceutical companies had abandoned ADEP as a drug option was because resistance to it developed "pretty readily", according to the study author.

And mutant bacterial cells that do not produce protease are completely resistant to ADEP when the drug is used on its own.

In their experiments, the team used ADEP in conjunction with conventional antibiotics such as rifampicin to wipe out Staphylococcus aureus germs.

"What we found is these mutants that do not have the protease... become susceptible to killing by any antibiotic essentially," said Lewis.

"That is why we get sterilisation when we combine ADEP with virtually any other antibiotic and that of course solves the problem of resistance."

Lewis said his team was working with a biotech company to take these results further.

In a comment also carried by Nature, bacteriologists Kenn Gerdes of Britain's Newcastle University and Hanne Ingmer of the University of Copenhagen rated the chances of a new antibiotic as "probable".

They also noted that Lewis and the team were testing a second class of antibiotic that also activates protease.

"This growing body of results generates hope that antibiotics for the treatment of persistent infections will be available in the future," they said.

Source: AFP
Advertisement

Advertisement
News A-Z
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
News Category
What's New on Medindia
Contraceptive Pills in Polycystic Ovary Syndrome (PCOS) Curtail Type 2 Diabetes Risk
Mushroom May Help Cut Down the Odds of Developing Depression
How to Battle Boredom during COVID
View all

Medindia Newsletters Subscribe to our Free Newsletters!
Terms & Conditions and Privacy Policy.

More News on:
Drug Toxicity Shigellosis Clinical Trials - Different Phases of the trial Signature Drug Toxicity MRSA - The Super Bug Food Safety for Health Antibiotics 

Recommended Reading
Drug Resistance - Antibiotic Resistance
Drug resistance is often a problem in malaria, tuberculosis, HIV, sexually transmitted diseases and ...
Antibiotics
Antibiotics are among the most used and abused medications. This article explains some general ......
MRSA - The Super Bug
MRSA infection is the most dreaded hospital or community acquired infection that can become ......
Typhoid and Paratyphoid Enteric Fevers
Typhoid and Paratyphoid Enteric Fevers are caused by bacteria called Salmonella typhi. Causes, ......
Clinical Trials - Different Phases of the trial
Clinical trials serve as a vital component for improving the treatment of medical conditions as they...
Drug Toxicity
Drug toxicity is an adverse reaction of the body towards a drug that results as a side effect of a d...
Shigellosis
Shigellosis or Bacillary Dysentery is a common cause of gastro-enteritis worldwide and can cause blo...

Disclaimer - All information and content on this site are for information and educational purposes only. The information should not be used for either diagnosis or treatment or both for any health related problem or disease. Always seek the advice of a qualified physician for medical diagnosis and treatment. Full Disclaimer

© All Rights Reserved 1997 - 2021

This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use