Scientists find new brain target for anxiety disorders

New Delhi : Mental illnesses, such as anxiety disorders, autism and schizophrenia are among the leading health disorders worldwide. Scientists now report a new brain target for potential future treatment of anxiety disorders.

Scientists at Universite de Montreal and its affiliated Montreal Clinical Research Institute (IRCM) have uncovered unique roles for a protein complex in the function of brain cell connectivity, as well as in specific cognitive behaviours.

The new findings, published in The EMBO Journal, could provide valuable therapeutic insights, say researchers led by Hideto Takahashi in collaboration with Steven Connor’s team at York University and Masanori Tachikawa’s team at Japan’s Tokushima University.

The junctions between two brain cells (neurons) are called synapses, which are essential for neuronal signal transmission and brain functions.

Defects in excitatory synapses, which activate signal transmission to target neurons, and those in synaptic molecules predispose to many mental illnesses.

Although defects in synapse organisation are linked to many neuropsychiatric conditions, the mechanisms responsible for this organisation were poorly understood.

Takahashi’s team has previously discovered a new protein complex within the synaptic junction which is only found in excitatory synapses.

The genes coding for these synapses are associated with anxiety disorders and autism, respectively.

The work carried out in the new study showed that this particular protein complex regulates the structural and functional maturation of excitatory synapses by regulating the phosphorylation, a biochemical protein modification, of many synaptic proteins, while disruption of this complex causes specific behavioural defects in mice.

High-resolution imaging of the mutant mice brains revealed abnormal synapse organisation, and further study of their signalling properties showed an increase in inactive synapses with defects in signal transmission.

Observing the behaviour of the mutant mice, the scientists saw that they exhibited elevated levels of anxiety, especially enhanced avoidance in unfamiliar conditions, and impaired social behaviours.