Tuberculosis (TB) is caused by a bacterial infection that spreads in the body because of its ability to easily bypass a weakened immune system. A research team at Michigan State University has discovered that a compound called ethoxzolamide, often prescribed to treat glaucoma, inhibits the TB bacteria’s strategy of escaping the immune system and multiplying.
Researchers used a fluorescent biosensor to screen 273,000 different compounds in order to find any that could fight the TB bacteria. After running several tests, they found that ethoxzolamide actually reduced the growth of the TB bacterium in macrophages (a specific type of white blood cell in the immune system where TB bacteria are known to invade and replicate). It also reduced symptoms of the disease in mice.
TB bacteria can sense changes in their environment, such as a shift in acidity/pH level, and adapt accordingly so that the immune system can’t fight them. According to the study’s senior author, Professor Robert Abramovitch, “The compound we found inhibits TB’s ability to detect acidic environments, effectively blindfolding the bacterium so it can’t resist the immune system’s assault.”
These findings, published in the journal Antimicrobial Agents and Chemotherapy, show that the ethoxzolamide compound may be able to effectively prevent the spreading of TB. It can also reduce the length of the treatment period, which can help resolve the issue of drug resistance. (Many TB patients’ bodies become resistant to the standard drugs because the course of treatment takes so long to work.)
Abramovitch notes that you don’t necessarily need to kill the TB bacteria to stop the disease—boosting the immune system by blocking the bacteria’s ability to evade it is also an effective means for stopping TB.
Sources for Today’s Article:
Johnson, B.K., et al., “The Carbonic Anhydrase Inhibitor Ethoxzolamide Inhibits the Mycobacterium tuberculosis PhoPR Regulon and Esx-1 Secretion and Attenuates Virulence,” Antimicrobial Agents and Chemotherapy 2015; doi: 10.1128/AAC.00719-15.
Paddock, C., “TB may be treatable with common glaucoma medication,” Medical News Today web site, July 24, 2015; http://www.medicalnewstoday.com/articles/297241.php.