A Potential Opioid Alternative from an Unexpected Source

Right now, Opioids are the most effective medications for treating pain, yet they pose significant risks for overdose and addiction. Since prescriptions for Opioid painkillers have caused an epidemic in overdoses during the past twenty years, with over 400,000 lives lost in the United States alone, researchers all across the world have been working diligently to develop medications that can treat pain without unleashing terrible side-effects.

According to a study published by the U.S. National Academy of Sciences, an obscure Australian fungus may the answer to the Opioid crisis. Earlier this month, an international team of scientists made a potential breakthrough in the search for Opioid-free painkillers when they discovered that a species of the Penicillium fungus has a unique molecular structure. Sixteen years ago, researchers from the University of Queensland harvested the fungus from mud on a boat ramp in an estuary of Tasmania’s Huon River.

After studying it under a microscope, researchers found that the fungus, Penicillium sp. MST-MF667, has three tetrapeptides with “right-handed” chirality. A tetrapeptide consists of four amino acids joined together by peptide bonds. Amino acids are components of proteins and neurotransmitters, and the chirality of amino acids refers to the shape of their molecular structures. For ease of reference, biologists tend to categorize chirality as “left-handed” or “right-handed.” Chirality affects how amino acids interact with other molecules. Most amino acids have “left-handed” chirality, so the discovery of “right-handed” tetrapeptides in a non-mammalian organism is significant because it allowed the scientists to study how these tetrapeptides interact with Opioid receptors. The scientists determined that they can function as μ-opioid agonists, meaning that they activate Opioid receptors in the central nervous system and alleviate pain. However, they do not pose the same risks as Opioid-based medications because they activates Opioid receptors in a different sequence.

Is Bilorphin the Next Major Painkiller?

By mimicking the structure of the Penicillium tetrapeptides, the team of scientists went on develop a new μ-opioid agonist called Bilorphin. In the words of the study, “Bilorphin is both a unique molecular tool that enhances understanding of MOPr biased signaling and a promising lead in the development of next generation analgesics.” The research team has already applied for a patent from the Australian government for Bilorphin. While it is possible that Bilorphin may one day overtake Opioids as the predominant painkillers in the medical system, Professor Macdonald Christie, a researcher for the study from the University of Sydney, emphasized that Bilorphin-based medication will most likely not be ready for sale for another ten years. Further research is necessary, but he explained that “if this proves successful and leads to a new medication, it will significantly reduce the risk of death by overdose from Opioid medications, such as Codeine.”