A research group at Tohoku University and the International Research Institute of Disaster Science has found that increased production of a protein called TNFα, which is one of the inflammatory cytokines in microglial cells in the brain, leads to sustained fear memory, and suppression of TNFα production eliminates fear memory. I found out that it would be done.
Post-traumatic stress disorder (PTSD) revives fear memory associated with traumatic experiences caused by disasters, accidents, violence, etc. with unpleasant emotions and physical reactions, which persists for a long period of time and interferes with daily life. It is a state that causes stress.So far, it has been pointed out that in the blood of patients with PTSD and in the brains of stressed model animals (mice), abnormalities in the amount of a group of proteins called cytokines that cause inflammation have been pointed out.
This time, we focused on the relationship between the functional changes of microglial cells that produce such inflammatory cytokines in the brain and the formation and persistence processes of fear memory, and used model mice for post-traumatic stress disorder (PTSD). I did some research.As a result, it was found that the production of TNFα in microglial cells in the brain increased with the behavioral abnormality due to the continuation of the memory of the fear experience, and the production decreased with the improvement of the behavioral abnormality.Furthermore, it was confirmed that administration of minocycline (tetracycline antibiotic), which is known to suppress the expression of inflammatory cytokines, suppresses TNFα and promotes improvement of behavioral abnormalities due to fear memory.
These results show that TNFα production of microglial cells in the brain plays an important role in the maintenance of fear memory, suggesting a relationship between intracerebral inflammation related to microglial function and the mechanism by which mental disorders are formed. Was done.It is expected that it will lead to the development of treatments for psychiatric disorders such as PTSD in the future.
