Early life low intensity stress experience modifies acute stress effects on juvenile brain cell proliferation of European sea bass ( D. Labrax )

Although it is well established that stress can disrupt complex cognitive functions, relatively little is known about how it influences visual processing, especially in terms of visual selective attention. In the current study, we used highly aversive images, taken from the International Affective Picture System, to induce acute, low-intensity stress while participants performed a visual discrimination task. Consistent with prior research, we found that anticipation of aversive stimuli increased overall amplitude of the N170, suggesting an increase in early sensory gain. More importantly, we found that stress disrupted visual selective attention. While in no-stress blocks, the amplitude of the face-sensitive N170 was higher when participants attended to faces rather than scenes in face–scene overlay images; this effect was absent under stress. This was because of an increase in N170 amplitude in the scene-attend condition under stress. We interpret these findings as suggesting that even low-intensity acute stress can impair participants' ability to filter out task-irrelevant information. We discuss our findings in relation to how even brief exposure to low-intensity stress may adversely impact both healthy and clinical populations.

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Genome-wide epigenomic stress response in the European sea bass (Dicentrarchus labrax, L.)

10.21203/rs.3.rs-48905/v2 ◽

2020 ◽

Author(s):

Madoka V. KRICK ◽

Erick DESMARAIS ◽

Athanasios SAMARAS ◽

Elise GUERET ◽

Arkadios DIMITROGLOU ◽

...

Keyword(s):

Stress Response ◽

Cytosine Methylation ◽

Acute Stress ◽

Dicentrarchus Labrax ◽

Sea Bass ◽

Blood Parameter ◽

European Sea Bass ◽

Genome Wide ◽

Stress Related Genes ◽

The Brain

Abstract Background: While the stress response inspired genome-wide epigenetic studies in vertebrate models, it remains mostly ignored in fish. We modified the epiGBS (epiGenotyping By sequencing) technique to explore changes in genome-wide cytosine methylation to a repeated acute stress challenge in the nucleated red blood cells (RBCs) of the European sea bass (Dicentrarchus labrax). This species is widely studied in both the natural and farmed environments, including issues regarding health and welfare.Results: We retrieved 501,108,033 sequencing reads after trimming, with a mean mapping efficiency of 73.0% (unique best hits). Minor changes in RBC methylome appear to manifest after the stress challenge. Only, fifty-seven differentially methylated cytosines (DMCs) close to 51 distinct stress-related genes distributed on 17 of 24 linkage groups (LGs) were detected between RBCs of pre- and post-stress individuals. However, literature surveys indicated that 38 of these genes were previously reported as differentially expressed in the brain of zebrafish, most of them involved in stress coping differences. DMC-related genes associated to the Brain Derived Neurotrophic Factor, a protein that favors stress adaptation and fear memory, appear especially relevant to integrate a centrally produced stress response.Conclusion: By putting forward DMCs associated to stress-related genes, we show that minimally invasive RBCs deserve more attention to investigate the epigenetic response to stress and components of the stress response without sacrificing fish. In parallel to blood parameter measurements (e.g. cortisol, glucose levels), and other molecular approaches (e.g. gene expression variation), features of the epigenetic landscape may offer new opportunities for biomonitoring components of the stress response in fish.

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Genome-Wide Epigenomic Stress Response in the European Sea Bass (Dicentrarchus Labrax, L.)

10.21203/rs.3.rs-48905/v1 ◽

2020 ◽

Author(s):

Madoka V. KRICK ◽

Erick DESMARAIS ◽

Athanasios SAMARAS ◽

Elise GUERET ◽

Arkadios DIMITROGLOU ◽

...

Keyword(s):

Stress Response ◽

Cytosine Methylation ◽

Acute Stress ◽

Dicentrarchus Labrax ◽

Sea Bass ◽

European Sea Bass ◽

Nucleated Red Blood Cells ◽

Genome Wide ◽

A Genome ◽

The Brain

Abstract Background: While the stress response inspired genome-wide epigenetic studies in vertebrate models, it remains mostly ignored in fish. We modified the epiGBS (epiGenotyping By sequencing) technique to explore changes in genome-wide cytosine methylation to a repeated acute stress challenge in the nucleated red blood cells (RBCs) of the European sea bass (Dicentrarchus labrax). This species is widely studied in both the natural and farmed environments, including issues regarding health and welfare.Results: We retrieved 501,108,033 sequencing reads after trimming, with a mean mapping efficiency of 73.0% (unique best hits). Fifty-seven differentially methylated cytosines (DMCs) close to 51 distinct stress-related genes distributed on 17 of 24 linkage groups (LGs) were detected between RBCs of pre- and post-stress individuals. Literature surveys indicated that thirty-eight of these genes were previously reported as differentially expressed in the brain of zebrafish, most of them involved in stress coping differences. DMC-related genes associated to the Brain Derived Neurotrophic Factor, a protein that favors stress adaptation and fear memory, are especially relevant.Conclusion: We provide an improved epiGBS protocol with increased multiplexing and sequencing capacities that offer new opportunities to improve data acquisition and to investigate important biological processes at a genome-wide level, such as the stress response. Minimally invasive RBCs deserve more attention to investigate the epigenetic response to stress without sacrificing fish.

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