Duke-NUS researchers have discovered that a growth factor protein, called neurotrophic factor (BDNF), and its receptor, tropomyosin receptor kinase B…
Duke-NUS researchers have discovered that a growth factor protein, called neurotrophic factor (BDNF), and its receptor, tropomyosin receptor kinase B (TrkB), affect social dominance in mice. The research has implications for understanding neurobiology of aggression and bullying.
“People and rodents are social animals.” Each interaction follows rules according to a social hierarchy. Failure to navigate in this hierarchy can be harmful. “explained senior author A / Prof. Hyunsoo Shawn Je, from the Neuroscience and Behavioral Disorders Signature Research Program at Duke-NUS Medical School.” Our paper may be the first to show that specific molecular pathways in specialized neurons in a particular area of the brain are important for a balanced navigation of social hierarchies. “
Difficulties to navigate in these hierarchies can lead to problems like aggression and bullying.” Given the high social cost of bullying and aggression, understanding of the biological causes is a step toward their effective prevention and treatment, “A / Prof. You added.
The activity in the brain is mediated by circuits consisting of excitatory nerve cells, which promote activity and GABA-ergural internalurons that inhibit and silence the excitatory activity. has shown that BDNF-TrkB signaling is important for maturation of GABA-ergur interurons o ch development of nerve circuits in the brain. However, researchers have not been able to identify the behavioral consequences of disturbed BDNF-TrkB signaling.
A / Prof. You are team-generated transgenic mice, in which the TrkB receptor was specifically removed in the GABAergic internuron of the brain that regulates emotional and social behavior, known as the corticolymic system. The transgenic mice exhibited unusually aggressive behavior when held together with normal mice. To understand the origin of this behavior, the team performed behavioral testing. They found that the mice were not aggressive to protect their territory. They were also not aggressive because they were stronger. The transgenic mice were injured more than other mice during aggression. Instead, their aggressive behavior was the result of increased struggles for status and dominance over other mice in the group.
The researchers found that due to the loss of BDNF-TrkB, GABA-ergic internalurons in these transgenic mice gave weaker inhibition to surrounding excitatory cells which became overactive. They continued to turn off excitatory neurons in a specific area of the transgenic brain brains, which re-established “excitatory / inhibitory” balance and “immediately reversed abnormal social dominance,” says Duke-NUS postdoctoral researcher. Shawn Pang Hao Tan, who was the first author of the magazine.
A significant amount of research has focused on the roles of family and peer networks in aggressive behavior. This study, along with other recently published findings, shows that genetic and biological factors can play an unexpected role in social behavior, says Je.
https://www.duke-nus.edu.sg/ news / neurobiology social aggression