Thursday, November 12, 2009

Kill the Bugs, Selectively

“Today, we have tuberculosis drugs you have to take for 9 months, why can’t we find one that work in three days”
- Bill Gates.

Tuberculosis (TB) is a chronic contagious disease caused by Mycobacterium tuberculosis (M.tb), is one of the leading caused of death worldwide. The WHO estimates about one-third of the world’s population is infected with M.tb, 10% of those infected will progress to active TB disease during their life time. The tuberculosis pandemic has been declared a global health emergency as the growing resistance of M.tb to Antibiotics coincides with the spread of risk factors such as HIV/AIDS and diabetes.

TB is a complex disease. The current TB drug regimen, a product of scientific advances of the 1960s, requires six to nine months of treatment for active, drug-susceptible TB. Unfortunately, many patients do not or cannot complete this treatment. Poor adherence and prescribing practices have led to the emergence of multi- and extensively drug resistant strains of TB (MDR-TB and XDR-TB) that increasingly defy current medicines and are spreading throughout many regions of the globe. The incidence of MRD- and XRD- TB demands renewed efforts in the development of novel class of fast acting anti TB chemotherapeutics.

Mycobacterium tuberculosis is one of the few bacterial species with a proteasome. A team of scientists led by researchers from Weill Cornell Medical College has found that some oxathiazolone compounds kill tuberculosis-causing bacteria by selectively inhibiting mycobacterial proteasomes without affecting human proteasomes. These compounds showing no apparent toxicity to mammalian cells. The oxathiazolone compounds are the first example of an anti-tubercular agent that inhibits protein breakdown. The ability of a brief exposure to oxathiazol-2-one compounds to inhibit M.tb proteasomes permanently makes it a potential target for anti-TB therapy.This findings may lead to drugs that destroy TB in dormant stage of lifecycle.