Modulation of Behavioral and Neurochemical Responses of Adult Zebrafish by Fluoxetine, Eicosapentaenoic Acid and Lipopolysaccharide in the Prolonged Chronic Unpredictable Stress Model

Long-term recurrent stress is a common cause of neuropsychiatric disorders. Animal models are widely used to study the pathogenesis of stress-related psychiatric disorders. The zebrafish (Danio rerio) is emerging as a powerful tool to study chronic stress and its mechanisms. Here, we developed a prolonged 11-week chronic unpredictable stress (PCUS) model in zebrafish to more fully mimic chronic stress in human populations. We also examined behavioral and neurochemical alterations in zebrafish, and attempted to modulate these states by 3-week treatment with an antidepressant fluoxetine, a neuroprotective omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA), a pro-inflammatory endotoxin lipopolysaccharide (LPS), and their combinations. Overall, PCUS induced severe anxiety and elevated norepinephrine levels, whereas fluoxetine (alone or combined with other agents) corrected most of these behavioral deficits. While EPA and LPS alone had little effects on the zebrafish PCUS-induced anxiety behavior, both fluoxetine (alone or in combination) and EPA restored norepinephrine levels, whereas LPS + EPA increased dopamine levels. As these data support the validity of PCUS as an effective tool to study stress-related pathologies in zebrafish, further research is needed into the ability of various conventional and novel treatments to modulate behavioral and neurochemical biomarkers of chronic stress in this model organism. © 2021, The Author(s).This research was supported solely by the Russian Science Foundation (RSF) grant 19‐15‐00053. K.A.D. is supported by the Special Rector’s Productivity Fellowship for SPSU PhD Students, and the lab is supported by St. Petersburg State University state budgetary funds (project ID 73026081). A.V.K. is the Chair of the International Zebrafish Neuroscience Research Consortium (ZNRC) and President of the International Stress and Behavior Society (ISBS, www.stress-and-behavior.com) that coordinated this collaborative multi-laboratory project. The consortium provided a collaborative idea exchange platform for this study, it is not considered as affiliation and did not fund the study. A.V.K. lab is supported by the Southwest University (SWU) Zebrafish Platform Construction Fund (Chongqing, China). The authors thank Professor Raul R. Gainetdinov (Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia) for his generous assistance with the HPLC studies in his laboratory. The funders had no role in the design, analyses, and interpretation of the submitted study, or decision to publish

Autonomous experimental studies resistojet with two autonomous heating elements for nanosatellites

The purpose of the work is to conduct autonomous experimental studies of an resistojet with two autonomous heating elements with a diameter of 4 mm. As a result of experimental studies of the resistojet, the heating dynamics of the micromotor structure and the working fluid (isobutane) in the power range from 5 W to 60 W is determined. Experimental studies have shown the possibility of using the proposed resistojet design with two autonomous heating elements not only on small spacecraft, but also on micro- and nanosatellites under conditions of limited on-board energy

Constructing the trajectory of a small spacecraft for flying around the base spacecraft for the purpose of external inspection and estimating the energy costs for the flyby maneuver

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