Having a traumatic experience is quite bad. If you have constantly experienced stress since before birth, you can be at an especially difficult time. Our emotions can be influenced by the infections experienced in the mother’s womb. This can result from two hits stresswhere an infection during pregnancy is followed by social stress during postpartum development.
A team of researchers from the University of Kyoto recently proposed to understand the mechanisms behind which the stress of two blows contributes to cerebral dysfunction and mental disorders. They conducted a comprehensive investigation of the social and cognitive behaviors of mice that have been exposed to this stress, paying special attention to behaviors similar to anxiety.
Previously, this team showed that acute inflammation in the cerebellum caused by an induced bacterial infection Neural plasticitywhich in turn can lead to hyperexcitability in the brain and at the beginning of depressive symptoms and similar to autism. However, exactly how two blow stress contributes to changes in the brain had not been clear.
Mice subject to current investigation was allowed to explore freely, revealing extensive behavior differences in two -stroke mice, correlating with abnormalities in the cerebellum. In particular, the researchers observed a significant increase in the number and rotation of MicrogliaThe primary immune cells found in the central nervous system. The study also revealed the neuronal loss in the cerebellum, a reduction in the action potential of the remaining cerebellar neurons and a decrease in functional connectivity throughout the brain.
“These results indicate cerebellar cognitive dysfunctions in animals exposed to two hits stress,” says Momoka Hikosaka team member. Exposure to such stress altered the microglial reactivity in the cerebella of male and females mice, which caused cerebellar dysfunction and behaviors that resemble psychiatric disorders.
But not everything is bad news. To rescue the exposed mice, the researchers used Microglia replacement To improve the effects of two blow stress. Deleting microglia can also be effective, but the systemic exhaustion of microglia generally weakens immunity, which makes the body more susceptible to infections.
“To address this limitation, our team made a specific microglia replacement of the cerebellum, which worked significantly well,” says the corresponding genus Ohtsuki, and adds: “We were impressed to observe that the female mice showed a remarkably higher stress resilience.”
This suggests that in some animals, sex differences in response to chronic inflammatory stress arise in the cerebellum in certain conditions. Consequently, personalized medicine medicine may require considering sex differences as an important factor, which could also be applied to neurodegenerative diseases and aging treatment.
In general, these findings provide new ways to understand the biological mechanisms behind mental disorders, and have the potential to transform scientific approaches and social attitudes towards the help of those affected.