Researchers Discover Why Old Schizophrenia Medicine Works on Antibiotic-Resistant Bacteria


Antibiotic-resistant bacteria is a huge problem all over the world: For example, 25Â percent to 50 percent of the inhabitants in southern Europe are resistant to staphylococci. In the Scandinavian countries it is less than 5 percent, but also here the risk of resistance is on the rise.

So any effective anti-inflammatory candidate is important to investigate -- even if the candidate is an antipsychotic that was originally developed to alleviate one of the hardest mental illnesses, schizophrenia.



"When we treat the bacteria with antibiotics alone, nothing happens - the bacteria are not even affected. But when we add both thioridazine and antibiotics, something happens: thioridazine weakens the bacterial cell wall by removing glycine (an amino acid) from the cell wall. In the absence of glycine, the antibiotics can attack the weakened cell wall and kill staphylococcus bacteria," explains Janne Kudsk Klitgaard, visiting scholar at the Department of Biochemistry and Molecular Biology, University of Southern Denmark.





"This will no longer be an antipsychotic, when scientists are finished with this task," she says.

Together with her colleagues Klitgaard tested thioridazine on roundworms in the laboratory and have seen that they were cured of staphylococci in the gut. Next step will be testing on mice and pigs.

Reference: Thioridazine induces major changes in global gene expression and cell wall composition in methicillin-resistant Staphylococcus aureus. USA300. PLOS ONE, May 17, 2013.

Source: University of Southern DenmarkÂ