Once called “consumption,” the disease we now refer to as tuberculosis was at one time romanticized as an artists’ disease and was thought to bring about a noble death. Quickly, however, as treatments were developed, tuberculosis became a disease of the less fortunate. As people with means were able to prevent or cure the disease, those without continued to suffer. Today, Mycobacterium tuberculosis (Mtb) infections have all but disappeared in higher-income countries, but continue to kill over a million people worldwide per year. Approximately 10.8 million people were infected in 2023 alone. COVID-19 briefly supplanted TB as the leading cause of death from a single infectious agent worldwide, but it was reported in October of this year that TB has taken the lead once more.
As with most other pathogens, TB is becoming resistant to traditional treatments. Multi-Drug Resistant (MDR) TB is becoming increasingly prevalent and is especially hard to treat. There are many reasons to develop novel Mtb treatments. Chiefly among them, certainly, is the moral obligation to prevent the deaths of millions of people. However, as MDR TB becomes more prevalent, higher-income countries will find themselves at risk unless new, effective antimicrobials are developed.
One study published in early October of this year uncovered a drug with the potential to inhibit growth of M. tuberculosis and other Mycobacterium species through novel means. As an added bonus, it appears the new drugs only target Mycobacterium species, leaving non-pathogenic bacteria unharmed. The authors based their new treatment on the compound sanguinarine, a natural benzo[c]phenanthridine alkaloid extract from the Sanguinaria canadensis or bloodroot plant. While sanguinarine is toxic in humans and is often a component of pseudoscientific treatments with no proven efficacy, it has shown some antibiotic properties against gram-negative bacteria. The authors synthesized 35 separate derivatives of the compound and tested their abilities to inhibit M. tuberculosis and other Mycobacterium. Two of the derivatives reduced survival rates of M. tuberculosis substantially, including strains that were resistant to frontline antibiotics. These two derivatives also appeared to be effective against intracellular and non-replicating Mtb.
The authors of the paper, from the Chinese Academy of Sciences and McGill University, believe these compounds represent a promising start for developing new anti-Mtb drugs in the future.
Read the full paper in the American Society for Microbiology’s Microbiology Spectrum here: https://doi.org/10.1128/spectrum.01246-24
