Seeking to realize tailor–made medicine for pain

Although it is well known that pain varies from patient to patient, tailor–made medicine for patients in pain has not yet been realized. Anesthesiologists often encounter patients whose pain persists after surgery, even though could be managed before the operation. It can be difficult to alleviate such prolonged pain a generic. In the future, to respond to pain in individual patients, it will be necessary to analyze pain–related signals that reflect not only the findings captured in conventional images and examinations, but also the physiological state, genetic background, and the state of the disease in patients. We have been searching for pain–related signals through basic research. Our functional MRI studies showed that the pain pathway was activated if analgesics were not administered under general anesthesia during surgery. This induced epigenomic modification in the spinal cord and brain, which was speculated to lead to prolonged pain as well as secondary emotional and sleep disorders. We also found that cytokine storms caused by surgery were the source of prolonged pain. Furthermore, in microRNA (miRNA) studies, early peripheral neuropathy significantly increased the expression of several miRNAs caused by inflam matory cytokines in the dorsal root ganglia. This led to concomitant increases in the expression of inflammation–derived exosomal miRNAs in the blood. We believe these findings will provide new information for next–generation pain treatment. In the future, “stratify” pain patients, it will be necessary to collect informa tion from procedures such as liquid biopsies. Individual and common para meters can be created based on mathematical analysis, data compression, and clustering analysis. Based on this information, we will create highly limited and diverse animal models of by individually introducing pain parameter–induced genes, and study pathological analysis and treatment methods. If such translational pain research becomes possible, tailor–made medicine for pain will become closer to reality.