mGluR2/3 blockade produces rapid and long-lasting reversal of anhedonia caused by chronic stress exposure

AbstractChronic stress is associated with impacting eating behavior, namely food choice and energy intake, with a shift towards more palatable and energy dense foods. Additionally, eating behavior is influenced by other psychological factors like mood and emotions. The categorization of people into eating types such as restrained, emotional, and external eaters has gained attraction. Reported changes in eating behavior due to psychological stress are only occasionally accompanied by measures of physiological hunger through ghrelin. The primary objective of this study was to investigate how chronic stress and acute cortisol reactivity affect active ghrelin secretion and how these outcomes account for different eating types. 16 healthy, young males (age: 23 ± 3 years, BMI: 22.5 ± 1.3kg/m2) with low (n = 8) and average-to-high (n = 8) chronic stress level were subjected to the Trier Social Stress Test (TSST) and a control version on two separate days. Active ghrelin, cortisol, glucose, and heart rate were measured throughout the test. Subjects rated their hunger by means of visual analog scale and current mood was assessed with the Positive and Negative Affect Scale (PANAS). In addition, participants filled out the Dutch Eating Behavior Questionnaire (DEBQ) to account for their subjective eating behavior. Overall ghrelin values where higher on the test day compared to the control day. Ghrelin values were also higher during the time leading up to the stress or control test (TSST) than during the conclusion of said tests. On both days, mean values for active ghrelin where higher in individuals with low chronic stress exposure compare to those with average-to-high chronic stress exposure. While values from test to control day decreased for lower stressed participants, they slightly increased for higher stressed participants. Cortisol responders displayed higher ghrelin values on test day than cortisol non-responders, but this association inverted for the control day. Results indicate that chronic stress influences acute stress response and further alters active ghrelin production, which in turn can influence eating behavior. Replication in a greater group of participants of differing weight and sex could yield a greater understanding of stress induced eating. Factors such as relaxation techniques and coping mechanisms could further improve our knowledge and evaluate treatment possibilities.

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Pair-housing of male and female rats during chronic stress exposure results in gender-specific behavioral responses

Hormones and Behavior ◽

10.1016/j.yhbeh.2005.01.004 ◽

2005 ◽

Vol 47 (5) ◽

pp. 620-628 ◽

Cited By ~ 51

Author(s):

C. Westenbroek ◽

T.A.B. Snijders ◽

J.A. den Boer ◽

M. Gerrits ◽

D.S. Fokkema ◽

...

Keyword(s):

Chronic Stress ◽

Behavioral Responses ◽

Female Rats ◽

Stress Exposure ◽

Male And Female ◽

Male And Female Rats ◽

Gender Specific

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Glutamate N-methyl-D-aspartate Receptor Antagonists Rapidly Reverse Behavioral and Synaptic Deficits Caused by Chronic Stress Exposure

Biological Psychiatry ◽

10.1016/j.biopsych.2010.12.015 ◽

2011 ◽

Vol 69 (8) ◽

pp. 754-761 ◽

Cited By ~ 617

Author(s):

Nanxin Li ◽

Rong-Jian Liu ◽

Jason M. Dwyer ◽

Mounira Banasr ◽

Boyoung Lee ◽

...

Keyword(s):

Chronic Stress ◽

Stress Exposure ◽

Receptor Antagonists ◽

Aspartate Receptor

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Chronic stress exposure, diurnal cortisol slope, and implications for mood and fatigue: Moderation by multilocus HPA-Axis genetic variation

Psychoneuroendocrinology ◽

10.1016/j.psyneuen.2018.10.003 ◽

2019 ◽

Vol 100 ◽

pp. 156-163 ◽

Cited By ~ 16

Author(s):

Lisa R. Starr ◽

Kimberly Dienes ◽

Y. Irina Li ◽

Zoey A. Shaw

Keyword(s):

Genetic Variation ◽

Chronic Stress ◽

Hpa Axis ◽

Stress Exposure ◽

Diurnal Cortisol

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Cocaine and chronic stress exposure produce an additive increase in neuronal activity in the basolateral amygdala

Addiction Biology ◽

10.1111/adb.12848 ◽

2019 ◽

Vol 26 (1) ◽

Author(s):

Soumyabrata Munshi ◽

J. Amiel Rosenkranz ◽

Aaron Caccamise ◽

Marina E. Wolf ◽

Claire M. Corbett ◽

...

Keyword(s):

Chronic Stress ◽

Neuronal Activity ◽

Basolateral Amygdala ◽

Stress Exposure ◽

Additive Increase

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Facilitation of the HPA Axis to a Novel Acute Stress Following Chronic Stress Exposure Modulates Histone Acetylation and the ERK/MAPK Pathway in the Dentate Gyrus of Male Rats

Endocrinology ◽

10.1210/en.2013-1918 ◽

2014 ◽

Vol 155 (8) ◽

pp. 2942-2952 ◽

Cited By ~ 21

Author(s):

Chantelle L. Ferland ◽

Erin P. Harris ◽

Mai Lam ◽

Laura A. Schrader

Keyword(s):

Dentate Gyrus ◽

Histone Acetylation ◽

Chronic Stress ◽

Hpa Axis ◽

Acute Stress ◽

Male Rats ◽

Stress Exposure ◽

Erk Activation ◽

Acute And Chronic Stress ◽

Acute Stressor

Evidence suggests that when presented with novel acute stress, animals previously exposed to chronic homotypic or heterotypic stressors exhibit normal or enhanced hypothalamic-pituitary-adrenal (HPA) response compared with animals exposed solely to that acute stressor. The molecular mechanisms involved in this effect remain unknown. The extracellular signal-regulated kinase (ERK) is one of the key pathways regulated in the hippocampus in both acute and chronic stress. The aim of this study was to examine the interaction of prior chronic stress, using the chronic variable stress model (CVS), with exposure to a novel acute stressor (2,5-dihydro-2,4,5-trimethyl thiazoline; TMT) on ERK activation, expression of the downstream protein BCL-2, and the glucocorticoid receptor co-chaperone BAG-1 in control and chronically stressed male rats. TMT exposure after chronic stress resulted in a significant interaction of chronic and acute stress in all 3 hippocampus subregions on ERK activation and BCL-2 expression. Significantly, acute stress increased ERK activation, BCL-2 and BAG-1 protein expression in the dentate gyrus (DG) of CVS-treated rats compared with control, CVS-treated alone, and TMT-only animals. Furthermore, CVS significantly increased ERK activation in medial prefrontal cortex, but acute stress had no significant effect. Inhibition of corticosterone synthesis with metyrapone had no significant effect on ERK activation in the hippocampus; therefore, glucocorticoids alone do not mediate the molecular effects. Finally, because post-translational modifications of histones are believed to play an important role in the stress response, we examined changes in histone acetylation. We found that, in general, chronic stress decreased K12H4 acetylation, whereas acute stress increased acetylation. These results indicate a molecular mechanism by which chronic stress-induced HPA axis plasticity can lead to neurochemical alterations in the hippocampus that influence reactivity to subsequent stress exposure. This may represent an important site of dysfunction that contributes to stress-induced pathology such as depression, anxiety disorders, and posttraumatic stress disorder.

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