Stress‐induced structural and functional modifications of astrocytes—Further implicating glia in the central response to stress

Glia ◽  
2019 ◽  
Author(s):  
Ciaran Murphy‐Royal ◽  
Grant R. Gordon ◽  
Jaideep S. Bains
Keyword(s):  
Central Response ◽  
Response To Stress

scholarly journals Cutaneous hypothalamic-pituitary-adrenal axis homolog: regulation by ultraviolet radiation

2011 ◽  
Vol 301 (3) ◽  
pp. E484-E493 ◽  
Author(s):  
Cezary Skobowiat ◽  
John C. Dowdy ◽  
Robert M. Sayre ◽  
Robert C. Tuckey ◽  
Andrzej Slominski
Keyword(s):  
Ultraviolet Radiation ◽  
Hpa Axis ◽  
Basal Layer ◽  
Local Stress ◽  
Hypothalamic Pituitary Adrenal ◽  
Central Response ◽  
Response To Stress ◽  
Significant Production ◽  
Skin Organ Culture ◽  
Pituitary Adrenal Axis

The hypothalamic-pituitary-adrenal (HPA) axis maintains basal and stress-related homeostasis in vertebrates. Skin expresses all elements of the HPA axis including corticotropin-releasing hormone (CRH), proopiomelanocortin (POMC), ACTH, β-endorphin (β-END) with corresponding receptors, the glucocorticoidogenic pathway, and the glucocorticoid receptor (GR). To test the hypothesis that cutaneous responses to environmental stressors follow the organizational structure of the central response to stress, the activity of the “cutaneous HPA” axis homolog was investigated after exposure to ultraviolet radiation (UVR) wavelengths of UVA (320–400 nm), UVB (280–320 nm), and UVC (100–280 nm) in human skin organ culture and in co-cultured keratinocytes/melanocytes. The level of stimulation of CRH, POMC, MC1R, MC2R, CYP11A1, and CYP11B1 genes was dependent on UV wavelengths and doses, with the highest effects observed for highly energetic UVC and UVB. ELISA and Western assays showed significant production of CRH, POMC, ACTH, and CYP11A1 proteins and of cortisol, with a decrease in GR expression only after UVB and UVC. However, β-END expression was also stimulated by UVA. Immunocytochemistry localized the deposition of the aforesaid antigens predominantly to the epidermis with additional accumulation of CRH, β-END, and ACTH in the dermis. UVR-stimulated CYP11A1 expression was seen in the basal layer of the epidermis and cells of adjacent dermis. Thus, the capacity to activate or change the spatial distribution of the cutaneous HPA axis elements is dependent on highly energetic wavelengths (UVC and UVB), implying a dependence of a local stress response on their noxious activity with overlapping or alternative mechanisms activated by UVA.

Dissecting the components of the central response to stress

2003 ◽  
Vol 6 (10) ◽  
pp. 1011-1012 ◽  
Author(s):  
Emeran A Mayer ◽  
Michael S Fanselow
Keyword(s):  
Central Response ◽  
Response To Stress

Aerodynamic and Acoustic Voice Measures Before and After an Acute Public Speaking Stressor

2020 ◽  
Vol 63 (10) ◽  
pp. 3311-3325
Author(s):  
Brittany L. Perrine ◽  
Ronald C. Scherer
Keyword(s):  
Fundamental Frequency ◽  
Salivary Cortisol ◽  
Public Speaking ◽  
Stress System ◽  
Before And After ◽  
Subglottal Pressure ◽  
Response To Stress ◽  
System Activation ◽  
Speaking Fundamental Frequency ◽  
Pituitary Adrenal Axis

Purpose The goal of this study was to determine if differences in stress system activation lead to changes in speaking fundamental frequency, average oral airflow, and estimated subglottal pressure before and after an acute, psychosocial stressor. Method Eighteen vocally healthy adult females experienced the Trier Social Stress Test (TSST) to activate the hypothalamic–pituitary–adrenal axis. The TSST includes public speaking and performing mental arithmetic in front of an audience. At seven time points, three before the stressor and four after the stressor, the participants produced /pa/ repetitions, read the Rainbow Passage, and provided a saliva sample. Measures included (a) salivary cortisol level, (b) oral airflow, (c) estimated subglottal pressure, and (d) speaking fundamental frequency from the second sentence of the Rainbow Passage. Results Ten of the 18 participants experienced a hypothalamic–pituitary–adrenal axis response to stress as indicated by a 2.5-nmol/L increase in salivary cortisol from before the TSST to after the TSST. Those who experienced a response to stress had a significantly higher speaking fundamental frequency before and immediately after the stressor than later after the stressor. No other variable varied significantly due to the stressor. Conclusions This study suggests that the idiosyncratic and inconsistent voice changes reported in the literature may be explained by differences in stress system activation. In addition, laryngeal aerodynamic measures appear resilient to changes due to acute stress. Further work is needed to examine the influence of other stress systems and if these findings hold for dysphonic individuals.

HYPERTROPHIC ADRENALS AND THEIR RESPONSE TO STRESS AFTER LESIONS IN THE MEDIAN EMINENCE OF TOTALLY HYPOPHYSECTOMIZED PIGEONS

1961 ◽  
Vol 37 (4) ◽  
pp. 565-576 ◽  
Author(s):  
Richard A. Miller
Keyword(s):  
Dose Response ◽  
Median Eminence ◽  
Response Curve ◽  
Liver Parenchyma ◽  
Dose Response Curve ◽  
Pars Distalis ◽  
Adrenal Enlargement ◽  
Response To Stress ◽  
Lethal Doses ◽  
Chromaffin Tissue

ABSTRACT Four per cent formaldehyde, insulin, or epinephrine in oil was injected for 5 days into pigeons subjected to varying degrees of hypophysectomy alone or together with large lesions in the median eminence and hypothalamus. Adrenals atrophied after the removal of the pars distalis alone or together with the neurohypophysis in untreated pigeons but showed markedly hypertrophic interrenal tissue (cortex in mammals) after treatment with formaldehyde or insulin. The slope of the dose-response curve was similar in operated and unoperated pigeons. The accumulation of bile in the liver parenchyma, which may occur after removal of the pars distalis, is an endogenous stress which was associated regularly with adrenal hypertrophy. After very large lesions of the median eminence and ventral hypothalamus in addition to total hypophysectomy, adrenals hypertrophied rather than atrophied, and the response to formaldehyde paralleled that in intact and »hypohysectomized« pigeons. Interrenal tissue was stimulated regularly; chromaffin tissue was partially degranulated, sometimes showed hyperplasia with colchicine, but only occasionally appeared hypertrophied. Epinephrine in nearly lethal doses caused only minimal adrenal enlargement. After adrenal denervation followed by hypophysectomy, the adrenals were still stimulated by formaldehyde. It appears that the interrenal tissue of the pigeon responds to a humoral stimulus not of hypophyseal origin in the absence of the hypophyseal-hypothalamic system.

PITUITARY AND BLOOD CORTICOTROPHIN CHANGES IN ADRENALECTOMIZED RATS MAINTAINED ON PHYSIOLOGICAL DOSES OF CORTICOSTEROIDS

1962 ◽  
Vol 39 (1) ◽  
pp. 79-86 ◽  
Author(s):  
J. R. Hodges ◽  
Joan Vernikos-Danellis
Keyword(s):  
Ascorbic Acid ◽  
Pituitary Gland ◽  
Replacement Therapy ◽  
Daily Treatment ◽  
Mild Stress ◽  
Acid Control ◽  
Small Doses ◽  
Response To Stress ◽  
Adrenalectomized Rats

ABSTRACT Pituitary and blood corticotrophin (ACTH) concentrations were estimated in adrenalectomized rats maintained on cortisol or crude adrenocortical extract (ACE) with and without ascorbic acid. Blood ACTH levels were also determined in similarly treated animals after subjection to mild stress. Thirty days after adrenalectomy there were marked rises in pituitary and blood corticotrophin concentration which were prevented by daily treatment with small doses of cortisol or ACE. In contrast to intact animals, adrenalectomized rats exhibited markedly increased adrenocorticotrophic responses to mild stress. This pituitary hyperexcitability was not diminished by replacement therapy with corticoids alone but was considerably reduced by ascorbic acid given in conjunction with ACE. It is suggested that corticoids control the rate at which ACTH is synthesised in the pituitary gland and that other factors, including ascorbic acid, control the excitability of the pituitary gland in its adrenocorticotrophic response to stress.

Compounds from Ilex paraguariensis extracts have antioxidant effects in the brains of rats subjected to chronic immobilization stress

2017 ◽  
Vol 42 (11) ◽  
pp. 1172-1178 ◽  
Author(s):  
Ana C. Colpo ◽  
Maria Eduarda de Lima ◽  
Marisol Maya-López ◽  
Hemerson Rosa ◽  
Cristina Márquez-Curiel ◽  
...  
Keyword(s):  
Oxidative Damage ◽  
Immobilization Stress ◽  
Brain Regions ◽  
Protective Role ◽  
Ilex Paraguariensis ◽  
Protective Effects ◽  
Species Formation ◽  
Lipid And Protein Oxidation ◽  
Response To Stress ◽  
Chronic Immobilization Stress

Immobilization induces oxidative damage to the brain. Ilex paraguariensis extracts (Mate) and their major natural compound, chlorogenic acid (CGA), exert protective effects against reactive oxygen species formation. Here, the effects of Mate and CGA on oxidative damage induced by chronic immobilization stress (CIS) in the cortex, hippocampus, and striatum were investigated. For CIS, animals were immobilized for 6 h every day for 21 consecutive days. Rats received Mate or CGA by intragastric gavage 30 min before every restraint session. Endpoints of oxidative stress (levels of lipid peroxidation, protein carbonylation, and reduced (GSH) and oxidized (GSSG) forms of glutathione) were evaluated following CIS. While CIS increased oxidized lipid and carbonyl levels in all brain regions, CGA (and Mate to a lesser extent) attenuated lipid and protein oxidation as compared with control groups. GSH/GSSG balance showed a tendency to increase in all regions in response to stress and antioxidants. Taken together, our results support a protective role of dietary antioxidants against the neuronal consequences of stress.

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