bioRxiv Science⌕ Search

Biology subjects

Balogh, Z.

Publications and source records attributed to Balogh, Z..

3 recordsLinked to original sources

Pretrauma cognitive traits predict trauma-induced fear generalization and associated prefrontal functioning in a longitudinal model of posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is a chronic psychiatric condition that develops in susceptible individuals exposed to traumatic stress, challenging clinicians to identify risk factors and mechanisms for mitigating vulnerability. Here we investigated behavioral predictors of high fear generalization, a core PTSD symptom, and its neural correlates longitudinally in rats. In a comprehensive behavioral test battery of emotional and cognitive function, pretrauma lower operant learning performance emerged as high predictor of fear generalization following trauma. Posttrauma operant training facilitated fear extinction, suggesting an overlap in neural circuits governing operant learning and fear expression. Neuronal activity mapping revealed significant changes in the medial prefrontal cortex (mPFC) in high fear generalizers, with alterations in CRH/VIP+ interneuron functioning. Silencing prefrontal Crh expression after fear memory consolidation enhanced mPFC activation and reduced fear expression, favoring resilience. These findings highlight operant learning and mPFC alterations as vulnerability markers and mediators of excessive fear generalization, with implications for prevention and targeted therapy in PTSD.

neuroscience↗

Endocannabinoid biomarkers of vulnerability to the development of trauma-induced generalized fear responses

Traumatic experiences result in the development of posttraumatic stress disorder (PTSD) in 10-25% of exposed individuals. While human clinical studies suggest that susceptibility is potentially linked to endocannabinoid (eCB) signaling, neurobiological PTSD susceptibility factors are poorly understood. Employing a rat model of PTSD, we characterized distinct resilient and susceptible subpopulations based on generalized fear, a core symptom of PTSD. In these groups, we assessed i.) eCB levels by mass spectrometry and expression variations of eCB system- and iii.) neuroplasticity-related genes by real-time quantitative PCR in the circuitry relevant in trauma-induced changes. Furthermore, employing supervised and semi-supervised machine learning based statistical analytical models, we assessed iv.) gene expression patterns with the most robust predictive power regarding PTSD susceptibility. According to our findings, in our model, generalized fear responses occurred with sufficient variability to characterize distinct resilient and susceptible subpopulations. Susceptible subjects showed lower prelimbic and higher ventral hippocampal levels of eCB 2-arachidonoyl-glycerol (2-AG) compared to resilient subjects. Ventral hippocampal 2-AG content positively correlated with the strength of fear generalization. Furthermore, susceptibility was associated with i.) neuronal prefrontal, hippocampal and amygdalar hypoactivity, ii.) marked decrease in the expression of genes of transcription factors modulating neuroplasticity and iii.) an altered expression pattern of eCB-related genes, including enzymes involved in eCB metabolism. Unsupervised and semi-supervised statistical approaches highlighted that hippocampal gene expression patterns possess strong predictive power regarding susceptibility. Taken together, the marked eCB and neuroplasticity changes in susceptible individuals associated with abnormal activity patterns in the fear circuitry possibly contribute to context coding deficits, resulting in generalized fear. HighlightsO_LIWe assessed endocannabinoid and neuroplasticity correlates of PTSD susceptibility C_LIO_LIPosttrauma generalized fear strength separates susceptible and resilient individuals C_LIO_LISusceptible individuals show altered endocannabinoid levels in the fear circuitry C_LIO_LINeuroplasticity and endocannabinoid gene expression patterns predict susceptibility C_LI

neuroscience↗

Improving anxiety research: novel approach to reveal trait anxiety through summary measures of multiple states

The reliability and validity of preclinical anxiety testing is essential for translating animal research into clinical use. However, the commonly used anxiety tests lack inter-test correlations and face challenges with repeatability. While translational animal research should be able to capture stable individual anxiety traits, the current approach employs a single type of test at a single time that only measures transient states of animals, heavily influenced by experimental conditions. Here, we propose a validated, optimized test battery capable of reliably capturing trait anxiety in rats and mice of both sexes. Instead of developing novel tests, we combined widely used tests (elevated plus-maze, open field and light-dark test) to provide instantly applicable adjustments for better predictive validity. We repeated these tests three times to capture behaviour across multiple challenges, which we combined to generate summary measures (SuMs). Our approach resolved between-test correlation issues and provided better predictions for subsequent outcomes under anxiogenic conditions or fear conditioning. SuMs were also able to reveal differences in anxiety in an etiological stress model. Finally, we tested our methods efficacy in discovering anxiety-related molecular pathways through RNA sequencing of the medial prefrontal cortex. Using SuMs, we identified four-times more molecular correlates of trait anxiety as compared to transient anxiety states, pointing out novel functional gene clusters. Furthermore, 16% of these molecular correlates of anxiety were replicated in amygdalar samples, as well. In summary, we provide a novel approach to capture trait anxiety in rodents, offering improved predictions for potential therapeutic targets for personalized medicine.

neuroscience↗