Opioid peptides for topical use
A new approach to the treatment of pain of inflammatory origin is proposed
LifeSciencesToday based on Charite materials: A new promising approach in the therapy of painThe treatment of pain caused by inflammation can be improved with the help of endogenous opioid peptides acting directly in the damaged tissue.
Scientists from the clinic of the Charite University of Berlin and the University of Paris. Descartes showed that pain can be successfully treated by targeting cells of the immune and nervous systems outside the brain or spinal cord.
A study by German and French scientists has been published in The FASEB Journal (Schreiter et al., Pain inhibition by blocking leukocytic and neuronal opioid peptidases in peripheral inflamed tissue).
Pain caused by inflammation, examples of which are acute postoperative pain and chronic pain in rheumatoid arthritis, is most common. However, her treatment is often difficult because she rarely responds to existing methods. In addition, opiates such as morphine cause serious side effects, including addiction, and representatives of the group of nonsteroidal anti-inflammatory drugs, for example, ibuprofen, can cause stomach ulcers, internal bleeding and lead to complications from the cardiovascular system. Activating opiate receptors in nerve cells outside the brain or spinal cord can relieve pain without serious side effects. This can be achieved by synthetic opiates or endogenous opioid peptides, for example, enkephalins and endorphins. However, opioid peptides are rapidly inactivated by two main enzymes – aminopeptidase N (aminopeptidase N, APN) and neutral endopeptidase (neutral endopeptidase, NEP), which weakens their analgesic effect.
Professor Halina Machelska-Stein and her group managed to prevent the breakdown of endogenous opioid peptides directly in the inflamed tissue. In an animal model, scientists have shown that the pain of inflammatory genesis can be relieved if both enzymes (APN and NEP) responsible for the inactivation of opioid peptides are suppressed with selective inhibitors. In preparations from immune and nerve cells expressing these enzymes, opioid peptides were rapidly destroyed. Their decay was prevented by enzyme inhibitors – bestatin, thiorpan and P8B. As a result, the sensation of pain was either noticeably reduced or completely disappeared.
"Targeting endogenous opioid peptides directly in damaged tissues can become a promising strategy for the treatment of inflammatory pain without serious side effects," says Professor Mahelska–Stein, commenting on the results of the study. In addition, blocking pain at the place of its origin can prevent the excitation of the nervous system, leading to the development of chronic pain.
Portal "Eternal youth" http://vechnayamolodost.ru10.12.2012