Source : https://dofollownet.com
Researchers from the "Consejo Superior de Investigaciones Científicas" (CSIC) have found a synthetic derivative of morphine which, when administered in rats, shows an analgesic effect one hundred times more powerful and twice as durable than morphine, as well as having fewer side effects.
The finding, published in the Journal of Medicinal Chemistry, opens the door to design new and better analgesics for the treatment of chronic and severe pain.
"Although in the past 40 years many new compounds with analgesic capacity have been discovered, there has been no significant progress for the treatment of chronic pain," says researcher Gregory Valencia. "This is the first time that a sugar (mannoside) derivative of morphine shows more analgesic capacity than the original drug".
Furthermore, said Valencia, "it does not produce tolerance after administration, nor any significant changes in metabolism." The researchers did not found any changes in blood pressure or heart rate in rats studied.
"Despite recent advances in medicinal chemistry and molecular biology, we still lacked an effective solution for chronic pain and severe. The most widely used drug, morphine, has significant side effects: respiratory depression, tolerance, dependence and constipation," says Gemma Arsequell, also a researcher at the Institute of Advanced Chemistry of Catalonia (Barcelona CSIC).
Morphine acts on the central nervous system, but only a small amount of the dose is able to cross the blood-brain barrier and reach the opioid receptors. After being administered morphine is metabolized by enzymes in the liver and up to 90% of the dose becomes metabolites M3G and M6G, more easily excreted by kidneys.
"It was long thought that these metabolites met only a detoxifying role and had no biological activity, however, it has been found that M6G does have pharmacological properties similar to those of morphine," says Valencia.
The researchers started from the M6G which is a natural metabolite of morphine and created a synthetic mannoside derivative that they called M6Man which appeared to be 100-fold more potent and twice as long lasting compared to morphine.Read »