[Potential application of maraviroc in the therapy of neuropathic pain]

According to International Association for the Study of Pain (IASP) neuropathic pain is defined as a pain caused by a lesion or disease of the somatosensory nervous system. In general population 7-8% adults suffer from chronic pain with neuropathic characteristic. The most common causes include: lumbar radiculopathy, postherpetic neuropathy, HIV infection, autoimmune diseases (multiple sclerosis), metabolic diseases (diabetic neuropathy), stroke or spinal cord injury. Current pharmacotherapy of neuropathic pain has insufficient effectiveness, so comprehension of neuropathic pain mechanism is necessary for research of new therapeutic methods. In the study we verify the analgesic effect of maraviroc (antagonist of the chemokine receptor - CCR5) and its potential role in the treatment of neuropathic pain. In the study we focused on dependency between opioid and chemokine receptors, because of similar structure between this receptors occurs cross-desensitization phenomenon. Chemokine antagonist maraviroc belongs to a group of entry inhibitors, antiretroviral drug. It enhances analgesic properties of opioids by inhibition of crossdesensitization of opioid's receptor. Application of maraviroc with morphine can reduce effective dosage of morphine 2,3 fold. Moreover, research show that prophylactic administration of maraviroc without opioid analgesics suppresses development of neuropathic pain symptoms. It has influence on glial phenotype, decreases secretion of proinflammatory cytokines and increases anti-inflammatory cytokine secretion. Furthermore it decreases expression of chemikine receptor mRNA and chemikine ligand's secreted by microglia and astrocytes as a result of nerve injury. We conclude that maraviroc has immunomodulatory properties, potentiates opioid analgesics effect, and can be used in neuropathic pain therapy as a potential co-analgesic.