Biology subjects

Edut, S.

Publications and source records attributed to Edut, S..

3 recordsLinked to original sources

bioRxiv2025

Post Adversity Changes in Nigro-Striatal Dopamine: a Mechanism for Anxiety Induced Exacerbated Innate Repetitive Behaviors.

Anxiety exacerbates symptoms in various psychiatric disorders. In conditions such as obsessive-compulsive disorder (OCD) or Tourette syndrome, anxiety intensifies stereotypic and repetitive behaviors. Rodent self-grooming, a structured, repetitive innate behavior, serves as an effective rodent platform for studying these behaviors in neuropsychiatric research. Anxiety is also linked to altered functioning of the dopamine (DA) system, particularly within the substantia-nigra pars compacta (SNc), the main DA source to the dorsal striatum through the nigro-striatal pathway. Striatal modulation by DA signal also plays a complex role in repetitive behaviors and OCD-like symptoms, suggesting this system as linking anxiety to the induced exacerbation of repetitive behavior. In the present study, we observed several long-term effects of anxiety inducing foot shock on grooming behavior. Recordings single unit neuronal activity in the SNc revealed distinct response patterns related to grooming behavior with changes in the magnitude and timing following the shock treatment. Notably, DA neurons of different nigro-striatal pathways demonstrated different changes in different response pattern type units. DA neurons projecting to the dorsolateral striatum (DLS) showed increase, while those targeting the dorsomedial striatum (DMS) exhibited decrease in transient activity -suggesting a shift in cortico-striatal circuitry of behavioral control. These neural changes were correlated with the observed behavioral alterations following adversity. Furthermore, targeted stimulation of DLS-projecting DA neurons rescued the anxiety-induced behavioral effects, highlighting the critical role of the nigro-striatal pathway to the DLS in mediating the interaction between anxiety and repetitive behaviors, thus offering future direction for mitigation of relevant psychiatric symptoms.

neuroscience↗

bioRxiv2022

Prefrontal Control of Innate Escape Behavior - A Neural Mechanism of Enhanced Posttraumatic Threat Detection

Innate defensive responses, while primarily instinctive, must also be flexible and highly adaptive to changes in risk assessment. As such, efficient innate escape behavior requires intricate processing to minimize reaction time while maximizing the success and adaptivity of the action. The superior colliculus (SC) is a subcortical sensorimotor integration center linking sensory threat information and escape. Adaptive changes in innate escape after learning could take a maladaptive turn after severe stress. Posttraumatic stress disorder (PTSD) is associated with long-term maladaptive changes after exposure to traumatic events, related to enhanced threat detection and reaction. Such long-term modifications are thought to involve the medial prefrontal cortex (mPFC), which is implicated in integrating learned emotional values into decisions that drive actions and behaviors. Here, in a series of experiments, we establish the crucial physiological role of specific mPFC neurons, exerting influence on the SC both directly and indirectly through the basal ganglia, in threat detection and reaction after adversity.

neuroscience↗

bioRxiv2022

The role of hippocampal CaMKII in resilience to trauma-related psychopathology

Traumatic stress exposure can form persistent trauma-related memories. However, only a minority of individuals develop post-traumatic stress disorder (PTSD) symptoms upon exposure. We employed a rat model of PTSD, which enables differentiating between exposed-affected and exposed-unaffected individuals. Two weeks after the end of exposure, animals were tested behaviorally, following an exposure to a trauma reminder, identifying them as trauma affected or unaffected. In light of the established role of hippocampal synaptic plasticity in stress and the essential role of Ca2+/calmodulin-dependent protein kinase II (CaMKII) in hippocampal based synaptic plasticity, in two separate experiments, we pharmacologically inhibited CaMKII or knocked-down CaMKII in the dorsal dentate gyrus of the hippocampus (dDG) following exposure to the same trauma paradigm. Both manipulations brought down the prevalence of affected individuals in the trauma- exposed population. A day after the last behavioral test, long-term potentiation (LTP) was examined in the dDG as a measure of synaptic plasticity. Trauma exposure reduced the ability to induce LTP, whereas, contrary to expectation, CaMKII-kd reversed this effect. Further examination revealed that reducing CaMKII expression, enables the formation of CaMKII-independent LTP, which may enable increased resilience in the face of a traumatic experience. The current findings further emphasize the pivotal role dDG has in stress resilience.

neuroscience↗