Biology subjects

Belujon, P.

Publications and source records attributed to Belujon, P..

3 recordsLinked to original sources

bioRxiv2025

The Role of Insular Anterior Parvalbumin GABAergic Interneurons in Impulsivity-Related and Alcohol-Seeking Behaviors

Alcohol use is a major global health concern, particularly during adolescence, a developmental period characterized by heightened impulsivity, a known risk factor for alcohol misuse. The insular cortex is critically involved in interoceptive processing and impulsivity regulation, and its activity is powerfully shaped by parvalbumin (PV)-expressing GABAergic interneurons. We hypothesized that developmental differences in PV interneuron activity within the insular cortex contribute to impulsivity-related behaviors and alcohol consumption. To investigate this, male C57BL/6 mice were assessed at two developmental stages: adolescence (postnatal day 28) and young adulthood (postnatal day 64). Impulsivity was measured using the Omission-Contingency Learning (OCL) task, while alcohol intake and preference were evaluated using a two-bottle choice paradigm. Adolescent mice displayed higher impulsivity and greater alcohol consumption than adults. Double immunofluorescence labeling (Fos+/NeuN+ and Fos+/PV+) showed that increased impulsivity was associated with reduced activation of PV interneurons in the insular cortex. Chemogenetic activation of PV interneurons in adult PV-Cre mice reduced impulsivity in the OCL task and decreased alcohol intake. These findings indicate that insular PV interneurons play a modulatory role in impulsive behavior and alcohol consumption, suggesting a potential therapeutic target for impulse-control and alcohol-use disorders.

neuroscience↗

bioRxiv2025

Environmental enrichment selectively restores brain metabolic activity during cocaine abstinence

BackgroundEnvironmental enrichment (EE) is a promising strategy to promote recovery from addiction, but its neurobiological mechanisms remain poorly understood. This study investigates how exposure to EE during abstinence dynamically affects brain neuroadaptations induced by voluntary intake of cocaine. MethodsUsing longitudinal 18FDG microPET imaging, we examined brain metabolic activity in rats following extended access cocaine self-administration. After establishing escalation of cocaine intake, rats were housed in either enriched or standard environments during a four-week abstinence period. Brain metabolic activity was assessed after one and four weeks of abstinence. ResultsCocaine self-administration produced widespread decreases in cortical metabolic activity, particularly in regions involved in executive function (orbitofrontal cortex, anterior cingulate) and interoception (insula), while increasing activity in emotional and motivational circuits (nucleus accumbens, amygdala, mesencephalon). EE selectively normalized these alterations through temporally distinct mechanisms: rapidly restoring nucleus accumbens and amygdala function while gradually affecting prefrontal cortical activity. After four weeks, rats housed in enriched environments showed significantly normalized metabolic activity in the orbitofrontal cortex and dorsolateral striatum compared to those in standard housing, with persistent changes in anterior cingulate cortex and ventral posterior hippocampus. ConclusionsOur findings reveal circuit-specific and temporally distinct effects of environmental enrichment on cocaine-induced brain alterations. These insights could inform the development of more targeted therapeutic approaches for addiction recovery.

neuroscience↗

bioRxiv2023

Sex-dependent effects of stress on insular cortex-to-nucleus accumbens synaptic plasticity

Stress is an important risk factor for the development of psychiatric disorders and men and women tend to react differently to stress. Sex differences are also observed in many stress-related psychiatric disorders such as depression, anxiety disorders or addiction. Therefore, identifying specific neuroadaptations induced by stress, in males and females, is a necessary step to the understanding of stress-related sex dimorphism in these disorders. Here, we tested the hypotheses that acute stress could affect plasticity in the anterior insular cortex (aIC)-nucleus accumbens core (NAcC) pathway, two structures involved in the stress response, in a sex-dependent manner. Using in vivo extracellular recordings in anesthetized rats, we show that synaptic plasticity in the aIC-NAcC pathway is different between male and female rats. Whereas in males, long-term potentiation and long-term depression were equally induced, in females, there was mostly a long-term potentiation induced. Moreover, stress affected synaptic plasticity in the aIC-NAcC differently in male and female rats. In males, stress induced a loss of long-term-depression that lasted for at least 24h, whereas in females, stress induced less neurons displaying LTP, which did not last. These results demonstrate that integration of aIC information to NAcC is different between males and females. This study provides mechanistic support for differential reactivity to stress between males and females that may relate to stress-related psychiatric disorders and sex dimorphism in these disorders.

neuroscience↗