scholarly journals Daily Limited Access to Sweetened Drink Attenuates Hypothalamic-Pituitary-Adrenocortical Axis Stress Responses

Endocrinology ◽  
2007 ◽  
Vol 148 (4) ◽  
pp. 1823-1834 ◽  
Author(s):  
Yvonne M. Ulrich-Lai ◽  
Michelle M. Ostrander ◽  
Ingrid M. Thomas ◽  
Benjamin A. Packard ◽  
Amy R. Furay ◽  
...  

Stress can promote palatable food intake, and consumption of palatable foods may dampen psychological and physiological responses to stress. Here we develop a rat model of daily limited sweetened drink intake to further examine the linkage between consumption of preferred foods and hypothalamic-pituitary-adrenocortical axis responses to acute and chronic stress. Adult male rats with free access to water were given additional twice-daily access to 4 ml sucrose (30%), saccharin (0.1%; a noncaloric sweetener), or water. After 14 d of training, rats readily learned to drink sucrose and saccharin solutions. Half the rats were then given chronic variable stress (CVS) for 14 d immediately after each drink exposure; the remaining rats (nonhandled controls) consumed their appropriate drinking solution at the same time. On the morning after CVS, responses to a novel restraint stress were assessed in all rats. Multiple indices of chronic stress adaptation were effectively altered by CVS. Sucrose consumption decreased the plasma corticosterone response to restraint stress in CVS rats and nonhandled controls; these reductions were less pronounced in rats drinking saccharin. Sucrose or saccharin consumption decreased CRH mRNA expression in the paraventricular nucleus of the hypothalamus. Moreover, sucrose attenuated restraint-induced c-fos mRNA expression in the basolateral amygdala, infralimbic cortex, and claustrum. These data suggest that limited consumption of sweetened drink attenuates hypothalamic-pituitary-adrenocortical axis stress responses, and calories contribute but are not necessary for this effect. Collectively the results support the hypothesis that the intake of palatable substances represents an endogenous mechanism to dampen physiological stress responses.

Endocrinology ◽  
2006 ◽  
Vol 147 (10) ◽  
pp. 4578-4588 ◽  
Author(s):  
Pauline M. Jamieson ◽  
Chien Li ◽  
Christina Kukura ◽  
Joan Vaughan ◽  
Wylie Vale

The endogenous corticotropin-releasing factor (CRF) type 2 receptor (CRFR2)-selective ligand urocortin 3 is expressed in discrete subcortical brain regions with fibers distributed mainly to hypothalamic and limbic structures. Close anatomical association between major urocortin 3 terminal fields and CRFR2 in hypothalamus, lateral septum, and medial amygdala (MEA) suggest it is well placed to modulate behavioral and hormonal responses to stress. Urocortin 3 was administered intracerebroventricularly to male rats under basal conditions or before a restraint stress, and circulating ACTH, corticosterone, glucose, and insulin were measured. Urocortin 3 activated the hypothalamic-pituitary-adrenal axis under basal conditions and augmented ACTH responses to restraint stress. Elevated blood glucose with lowered insulin to glucose ratios in both groups suggested increased sympathetic activity. Circulating catecholamines were also increased by urocortin 3, providing additional evidence for sympathoadrenomedullary stimulation. Intracerebroventricular urocortin 3 increased vasopressin mRNA expression in the parvocellular division of the hypothalamic paraventricular nucleus, whereas CRF expression was unchanged, providing a possible mechanism by which urocortin 3 mediates its actions. Urocortin 3 mRNA expression was examined after exposure to stress-related paradigms. Restraint increased levels in MEA with a trend to increased expression in the rostral perifornical hypothalamic area, whereas hemorrhage and food deprivation decreased expression in MEA. Adrenalectomy markedly increased expression in the rostral perifornical hypothalamic area, and high-level corticosterone replacement restored this to control levels. The evidence that urocortin 3 has the potential to influence hormonal components of the stress response and the changes in its expression levels after stressors is consistent with a potential function for the endogenous peptide in modulating stress responses.


Author(s):  
Renae Charalambous ◽  
Troy Simonato ◽  
Matthew Peel ◽  
Edward Narayan

Koalas (Phascolarctos cinereus) are one of Australia's most charismatic native small marsupial species. Unfortunately, populations of koalas are rapidly declining throughout Australia and they continue to face increasing pressure from a changing ecosystem. Negative stimulants in the environment can elicit stress responses through activation of the hypothalamic-pituitary-adrenal (HPA) axis. Depending on the duration of the negative stimulant, the stress response can lead to either acute or chronic side effects, and is shown through the activation of the neuroendocrine stress system and the release of glucocorticoids (e.g., cortisol). Wild koalas entering clinical care face novel stressors that can be out of a wildlife carer's control. In this pilot study, we monitored physiological stress in three wild koalas at a wildlife rehabilitation centre in New South Wales, Australia. Acute and chronic stress was indexed non-invasively, with faecal samples taken to evaluate acute stress, and fur samples taken to evaluate chronic stress. Sampling occurred sporadically over four months, from the start of September 2018 to the end of December 2018. Results attempt to understand the stress response of koalas to negative stimulants in the environment by comparing faecal glucocorticoids on days where a known stressor was recorded with days where no known stressor was recorded. Furthermore, variations in faecal and fur glucocorticoids were compared between the three koalas in this study. To our knowledge, this is the first evidence of stress tracking of wild rescued koalas in a sanctuary. We suggest that further monitoring of baseline, acute and chronic stress will be needed to better understand how koalas respond to negative stimulants associated with clinical care.


1999 ◽  
Vol 276 (6) ◽  
pp. E1136-E1145 ◽  
Author(s):  
Brian I. Labow ◽  
Wiley W. Souba ◽  
Steve F. Abcouwer

Skeletal muscle exports glutamine (Gln) and increases the expression of the enzyme glutamine synthetase (GS) in response to physiological stress. Acute stress or direct glucocorticoid administration raises muscle GS mRNA levels dramatically without a parallel increase in GS protein levels. In the lung, this discrepancy is caused by feedback destabilization of the GS protein by its product Gln. It was hypothesized that muscle GS protein levels increase during stress only when the intracellular Gln pool has been depleted. Adult male rats were injected with the glucocorticoid hormone dexamethasone (DEX) to mimic the acute stress response and with the GS inhibitor methionine sulfoximine (MSO) to deplete muscle Gln stores. DEX increased GS mRNA levels by 2.8-fold but increased GS protein levels by an average of only 40%. MSO diminished muscle GLN levels by 68% and caused GS protein levels to rise in accordance with GS mRNA. Chronic stress was mimicked using 6 days of MSO treatment, which produced anorexia, 23% loss of body weight, and 64% decrease in muscle Gln levels, as well as pronounced increases in both muscle GS mRNA (26-fold) and protein levels (35-fold) without elevation of plasma glucocorticoid levels. Calorie-restricted pair-fed animals exhibited lesser increases in muscle GS mRNA (8-fold) and protein levels (5-fold) without a decline in muscle Gln content. Thus regulation of GS expression in both acute and chronic stress involved both transcriptional and posttranscriptional mechanisms, perhaps affected by muscle Gln content.


2018 ◽  
Author(s):  
Franziska Lautenbach

BACKGROUND Dealing with stress is of central importance. Lately, smartphone applications (apps) are deployed in stress interventions as they offer maximal flexibility for users. First results of experimental studies show that anti-stress apps effect subjective perception of stress positively (Ly et al., 2014). However, current literature lacks studies on physiological stress reactions (e.g., cortisol), although they are of special interest to health issues. OBJECTIVE Therefore, the aim of this study was to investigate the effectiveness of an anti-stress app in chronic and acute stress reduction on a physiological (cortisol) and psychological level (subjective perception of stress) in comparison to a face-to-face and a control group in a pre-post design, for the first time. METHODS Sixty-two participants took part in the pretesting procedure (drop-out of 53 %). Based on age, gender, physical activity and subjectively perceived acute stress due to the Trier Social Stress Test for groups (TSST-G; von Dawans et al., 2011) as well as based on subjectively chronic stress assessed during the pretest, participants were parallelized in three groups (anti-stress-app: n = 10, face-to-face: n = 11, control group: n = 9). RESULTS After six weeks of the cognitive-based resource-oriented intervention, participants were exposed to the TSST-G for post testing. Results did not show a change of cortisol secretion or cognitive appraisal of the acute stressor. Further, no changes were detected in the chronic physiological stress reaction. CONCLUSIONS Possible causes are discussed extensively. CLINICALTRIAL no


2003 ◽  
Vol 44 (4) ◽  
pp. 327-337 ◽  
Author(s):  
S Retana-Márquez ◽  
H Bonilla-Jaime ◽  
G Vázquez-Palacios ◽  
R Martínez-García ◽  
J Velázquez-Moctezuma

2017 ◽  
Vol 57 (3) ◽  
pp. 401 ◽  
Author(s):  
C. Burnard ◽  
C. Ralph ◽  
P. Hynd ◽  
J. Hocking Edwards ◽  
A. Tilbrook

There is considerable interest in the potential for measuring cortisol in hair as a means of quantifying stress responses in human and non-human animals. This review updates the rapid advancement in our knowledge of hair cortisol, methods for its measurement, its relationship to acute and chronic stress, and its repeatability and heritability. The advantages of measuring cortisol in hair compared with other matrices such as blood, saliva and excreta and the current theories of the mechanisms of cortisol incorporation into the fibre are described. Hair cortisol as a measure of the physiological response to stress in a variety of species is presented, including correlations with other sample matrices, the relationship between hair cortisol and psychosocial stress and the repeatability and heritability of hair cortisol concentrations. Current standards for the quantification of hair cortisol are critically reviewed in detail for the first time and gaps in technical validation of these methods highlighted. The known effects of a variety of sources of hair cortisol variation are also reviewed, including hair sampling site, sex, age and adiposity. There is currently insufficient evidence to conclude that cortisol concentration in hair accurately reflects long-term blood cortisol concentrations. Similarly, there is a lack of information surrounding the mechanisms of cortisol incorporation into the hair. This review highlights several directions for future research to more fully validate the use of hair cortisol as an indicator of chronic stress.


Endocrinology ◽  
2006 ◽  
Vol 147 (4) ◽  
pp. 2008-2017 ◽  
Author(s):  
Michelle M. Ostrander ◽  
Yvonne M. Ulrich-Lai ◽  
Dennis C. Choi ◽  
Neil M. Richtand ◽  
James P. Herman

Chronic stress induces both functional and structural adaptations within the hypothalamo-pituitary-adrenocortical (HPA) axis, suggestive of long-term alterations in neuroendocrine reactivity to subsequent stressors. We hypothesized that prior chronic stress would produce persistent enhancement of HPA axis reactivity to novel stressors. Adult male rats were exposed to chronic variable stress (CVS) for 1 wk and allowed to recover. Plasma ACTH and corticosterone levels were measured in control or CVS rats exposed to novel psychogenic (novel environment or restraint) or systemic (hypoxia) stressors at 16 h, 4 d, 7 d, or 30 d after CVS cessation. Plasma ACTH and corticosterone responses to psychogenic stressors were attenuated at 4 d (novel environment and restraint) and 7 d (novel environment only) recovery from CVS, whereas hormonal responses to the systemic stressor were largely unaffected by CVS. CRH mRNA expression was up-regulated in the paraventricular nucleus of the hypothalamus (PVN) at 16 h after cessation of CVS, but no other alterations in PVN CRH or arginine vasopressin mRNA expression were observed. Thus, in contrast to our hypothesis, reductions of HPA axis sensitivity to psychogenic stressors manifested at delayed recovery time points after CVS. The capacity of the HPA axis to respond to a systemic stressor appeared largely intact during recovery from CVS. These data suggest that chronic stress selectively targets brain circuits responsible for integration of psychogenic stimuli, resulting in decreased HPA axis responsiveness, possibly mediated in part by transitory alterations in PVN CRH expression.


Endocrinology ◽  
2014 ◽  
Vol 155 (8) ◽  
pp. 2942-2952 ◽  
Author(s):  
Chantelle L. Ferland ◽  
Erin P. Harris ◽  
Mai Lam ◽  
Laura A. Schrader

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.


2005 ◽  
Vol 65 (1) ◽  
pp. 69-75 ◽  
Author(s):  
Maria Luiza Nunes Mamede Rosa ◽  
Francisco Silveira Guimarães ◽  
Rubia Maria Welfort de Oliveira ◽  
Cláudia Maria Padovan ◽  
Ronald Carl Alan Pearson ◽  
...  

2005 ◽  
Vol 35 (3) ◽  
pp. 541-556 ◽  
Author(s):  
Eric Mellina ◽  
Scott G Hinch ◽  
Edward M Donaldson ◽  
Greg Pearson

The impacts associated with streamside clear-cut logging (e.g., increased temperatures and sedimentation, loss of habitat complexity) are potentially stressful to stream-dwelling fish. We examined stream habitat and rainbow trout physiological stress responses to clear-cut logging in north-central British Columbia using 15 streams divided into three categories: old growth (reference), recently logged (clear-cut to both banks 1–9 years prior to the study), and second growth (clear-cut 25–28 years prior to the study). We used plasma cortisol and chloride concentrations as indicators of acute stress, and interrenal nuclear diameters, impairment of the plasma cortisol response, and trout condition and length-at-age estimates as indicators of chronic stress. No statistically significant acute or chronic stress responses to streamside logging were found, despite increases in summertime stream temperatures (daily maxima and diurnal fluctuations) and a reduction in the average overall availability of pool habitat. Our observed stress responses were approximately an order of magnitude lower than what has previously been reported in the literature for a variety of different stressors, and trout interrenal nuclear diameters responses to the onset of winter were approximately five times greater than those to logging. The overall consistency of our results suggests that the impacts of streamside clear-cut logging are not acutely or chronically stressful to rainbow trout in our study area.


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