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

Experimental Drug Shows Promise Against Latent TB Bacteria

by VR Sreeraman on November 29, 2008 at 12:27 PM
Font : A-A+

 Experimental Drug Shows Promise Against Latent TB Bacteria

Researchers from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, have determined how a promising drug candidate attacks the bacterium that causes tuberculosis (TB).

The finding could help scientists develop ways to treat dormant TB infections, and suggests a strategy for drug development against other bacteria as well.

Advertisement

One-third of the world's population is infected with Mycobacterium tuberculosis (M. tb), the bacteria that cause TB.

In a previous study, lead author Clifton E. Barry, III, Ph.D., of the National Institute of Allergy and Infectious Diseases (NIAID), and his colleagues found that M. tb mutants lacking a specific bacterial enzyme were resistant to PA-824, but at that time, they did not know the function of the enzyme.
Advertisement

"It took several years, but at last we were able to recreate in the test tube what happens inside mycobacterial cells when the bacterial enzyme, which we named Ddn, and a second bacterial component called a cofactor, interact with PA-824," said Barry.

They found that the key event in PA-824 metabolism is the production of nitric oxide (NO) gas.

"This highly reactive molecule is akin to a bomb blast that kills the bacteria from within," he added.

No gas is produced naturally by certain immune system cells after they engulf M. tb or other bacteria. This is one way that people with healthy immune systems can contain M. tb infection.

However, this natural immune response is not always enough to completely rid the body of TB bacteria. In essence, PA-824 performs similarly to the No-producing immune cells, but the drug's effect is more specific and triggered only after it enters the bacteria.

The non-dividing M. tb bacteria characteristic of latent TB infections are walled off by immune cells that aggregate around the bacteria to form a body called a granuloma. Oxygen levels are low inside granulomas.

In the new study, the researchers observed that No-generation during PA-824 metabolism is greatest when oxygen levels are low. This observation suggests how PA-824 may work against non-dividing M. tb. PA-824 was originally designed to work best under aerobic, or oxygenated, conditions.

Barry said that with this new understanding of how the bacterial enzyme and cofactor act on PA-824 under low-oxygen conditions, scientists could design drugs with a chemical structure similar to PA-824 but optimize them from the start to behave best under low-oxygen conditions.

The study is published in the Nov. 28 issue of Science.

Source: ANI
SRM
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
Advertisement
News Category
What's New on Medindia
Cochlear Implants may Consequently Drive Hearing Loss
E-cigarettes Use Linked to Erectile Dysfunction
Memory Loss - Can it be Recovered?
View all

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

More News on:
Drug Toxicity Tuberculosis AIDS/HIV Shigellosis Signature Drug Toxicity Silicosis Screening Tests for Tuberculosis 

Recommended Reading
Tuberculosis
Tuberculosis, caused by Mycobacterium tuberculosis, primarily affects the lung. It may spread to ......
Sputum Test
Pulmonary tuberculosis is caused by Mycobacterium tuberculosis.It primarily involves lungs and ......
Tuberculosis in Children - Magnitude of the problem
In India nearly 3-4 million children have tuberculosis and another 94 million are at risk for this ....
Controlling Tuberculosis -The Indian Chapter
India aims to bring down the prevalence of TB by 50 per cent by 2015 and to completely eradicate it ...
AIDS/HIV
"AIDS is an epidemic disease, a potentially preventable, deadly infection for which there is no cure...
Drug Toxicity
Drug toxicity is an adverse reaction of the body towards a drug that results as a side effect of a d...
Screening Tests for Tuberculosis
Tuberculin skin test and Interferon – Release Assays are tests used to screen for tuberculosis....
Shigellosis
Shigellosis or Bacillary Dysentery is a common cause of gastro-enteritis worldwide and can cause blo...
Silicosis
Silicosis is a lung disease caused by inhalation of crystalline free silica dust. It is characterise...

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