Powerful chemicals in the brains and nervous systems of the lowly cockroach, as well as the swarming locust, can lay waste to antibiotic-resistant staph and dangerous forms of E. coli bacteria, fueling hope that they might be the basis of new antibiotics to replace those rendered useless against these infectious species, according to British researchers.
Simon Lee, a postgraduate researcher at the University of Nottingham's School of Veterinary Medicine and Science, has focused his work on potential antimicrobial compounds from insects. He and his colleagues found up to nine different antibacterial molecules in cockroach and locust brains and nervous system tissues that did not damage human cells, he reported Tuesday at the fall meeting of the Society for General Microbiology, Europe's largest microbiology society.
"We hope that these molecules could eventually be developed into new treatments for E. coli and methicillin-resistant staphylococcus aureus (MRSA) infections that are increasingly resistant to current drugs," Lee said. They could potentially provide alternatives to the shrinking arsenal of effective antibiotics, with their "serious and unwanted side effects."
Lee, whose research is sponsored by the university and the U.K. Ministry of Defense, describes insects as "a relatively untapped source of pharmaceutical drug-leads," on his Web page at the University of Nottingham.
Lee said it wasn't surprising that cockroaches and locusts, which typically make their homes in unsanitary and unhygienic environments, would produce their own germ killers. He said it was "logical that they would have developed ways of protecting themselves against microorganisms."
Lee's academic supervisor, Naveed Khan, an associate professor of molecular biology at Nottingham, noted that microbes such as MRSA "have developed resistance against the chemotherapeutic artillery that we throw at them. They have shown the ability to cause untreatable infections and have become a major threat in our fight against bacterial diseases."
Khan, Lee and the rest of the research team have been testing the strength of germ killers isolated from locusts and cockroaches against other emerging superbugs, including Acinetobacter, Pseudomonas and Burkholderia, which are growing increasingly unresponsive to current antibiotics.
"Already there are infections that are untreatable due to resistance, and nothing in the pipeline that offers much hope," said Dr. Connie Price, chief of infectious diseases for the Denver Health & Hospital Authority, who was not involved in the study. She said scientists have looked for promising compounds in the skin of frogs and sharks and in other plants. They've been investigating compounds that interfere with the ability of bacteria to communicate with each other, and are exploring out-of-the-box approaches to interfering with bacterial growth.