The solution developed by the team of Prof. Andrzej Lipkowski from M. Mossakowski Institute of Clinical and Experimental Medicine PAS in Warsaw received the Grand Jury prize and the gold medal with distinction during the recent exhibition of inventions BRUSSELS INNOVA.

Prof. Andrzej Lipkowski explained in an interview with that morphine is an opioid compound, which has a strong analgesic effect. In Poland, it is used quite often, especially to relieve the suffering of patients with very severe or chronic pain. However, in order to effectively eliminate chronic pain, the dose often has to be gradually increased. And the use of morphine is associated with unpleasant side effects: not only numbness, addiction and respiratory depression. The problem, which turns out to be most troublesome in the case of opioid compounds, is constipation. The affliction is sometimes so annoying that doctors and patients accept some of the pain and restrict the use of the drug.

"Often, even a single administration of opioid compounds causes constipation" - admitted Lipkowski. He gave an example women who have opioids administered to the spinal cord during labor often then suffer from constipation for several days. The undesirable effect becomes stronger with long-term use, especially with morphine administered orally in tablet form.

The researcher explained that morphine attaches not only to receptors in the nervous system, reducing the sensation of pain, but also to receptors in the gastrointestinal tract, inhibiting peristalsis.

Scientists from the Institute of Clinical and Experimental Medicine PAS, however, managed to develop a compound that prevents constipation after taking morphine. This compound attaches the same receptors as opioids in the gastrointestinal tract to and thereby blocks the place for opioids. The compound does not pass through the intestinal barrier into the blood or nervous system, and therefore it does not block opioid analgesic activity.

The compound has been developed at the Institute of Clinical and Experimental Medicine PAS for NORMOLIFE, international project in which researchers look for new drugs to treat pain associated with terminal cancer.

According to Prof. Lipkowski, the idea came up during the research on endogenous (naturally secreted by the body) opioid compounds which have an analgesic effect. These include endorphins and enkephalins them, also known as the "happiness hormones". Lipkowski explained that morphine affects exactly the same mechanism , as endorphins. "With endorphins we do not need to take anything to feel like getting high" - said Prof. Lipkowski. The scientist explained that although endorphins and morphine work on the same system, they have different chemical structures. "Opioids are designed to pass through all biological barriers, from digestive system through the blood to the central nervous system. Unlike these, the structure of endorphins prevents them from travelling outside the brain, where they are secreted" - explained the researcher.

"In search of new analgesic compounds we found derivatives of endorphins, which block the effects of morphine, but are unable to pass through natural barriers. Such compound has no use as a pain reliever, but it will prevent constipation, if administered orally with morphine" - says researcher.

According to the scientist, there already is a drug on the market that eliminates constipation caused by morphine. It is built differently, being a derivative of morphine, not endorphins. Researchers at the Institute of Clinical and Experimental Medicine PAS are hoping that their solution will be safer and more effective than the one already available.

Before the newly developed drug is marketed, a lot of research on the effects of the compound it is still necessary. Prof. Lipkowski expects that all the required procedures will take at least several years.

PAP - Science and Scholarship in Poland, Ludwika Tomala

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