» Articles » PMID: 32734320

Chronic Stress Inhibits Hypothalamus-pituitary-thyroid Axis and Brown Adipose Tissue Responses to Acute Cold Exposure in Male Rats

Overview
Publisher Springer
Specialty Endocrinology
Date 2020 Aug 1
PMID 32734320
Citations 1
Authors
Affiliations
Soon will be listed here.
Abstract

Purpose: Cold exposure activates the hypothalamus-pituitary-thyroid (HPT) axis, response blunted by previous acute stress or corticosterone administration. Chronic stressors can decrease serum T3 concentration, and thyrotropin-releasing hormone (Trh) expression in the paraventricular nucleus (PVN), but impact on the response to cold is unknown; this was studied in rats submitted to daily repeated restraint (rRes) that causes habituation of hypothalamus-pituitary-adrenal (HPA) axis response, or to chronic variable stress (CVS) that causes sensitization and hyperreactivity.

Methods: Wistar male adult rats were submitted to rRes 30 min/day, or to CVS twice a day, for 15 days. On day 16, rats were exposed 1 h to either 5 or 21 °C. Parameters of HPT and HPA axes activity and of brown adipose tissue (BAT) cold response were measured; gene expression in PVN and BAT, by RT-PCR; serum hormone concentration by radioimmunoassay or ELISA.

Results: Compared to naïve animals, Crh and corticosterone concentrations were attenuated at the end of rRes, but increased at the end of CVS treatments. Cold exposure increased mRNA levels of Crh, Trh, and serum concentration of thyrotropin in naïve, but not in rRes or CVS rats; corticosterone increased in all groups. Cold induced expression of thermogenic genes in BAT (Dio2 and Ucp1) in naïve but not in stressed rats; Adrb3 expression was differentially regulated.

Conclusion: Both types of chronic stress blunted HPT and BAT responses to cold. Long-term stress effects on noradrenergic and/or hormonal signaling are likely responsible for HPT dysfunction and not the type of chronic stressor.

Citing Articles

Sex Dimorphic Responses of the Hypothalamus-Pituitary-Thyroid Axis to Energy Demands and Stress.

Parra-Montes de Oca M, Sotelo-Rivera I, Gutierrez-Mata A, Charli J, Joseph-Bravo P Front Endocrinol (Lausanne). 2021; 12:746924.

PMID: 34745011 PMC: 8565401. DOI: 10.3389/fendo.2021.746924.

References
1.
Morrison S . Efferent neural pathways for the control of brown adipose tissue thermogenesis and shivering. Handb Clin Neurol. 2018; 156:281-303. DOI: 10.1016/B978-0-444-63912-7.00017-5. View

2.
Nedergaard J, Cannon B . Brown adipose tissue as a heat-producing thermoeffector. Handb Clin Neurol. 2018; 156:137-152. DOI: 10.1016/B978-0-444-63912-7.00009-6. View

3.
Rondeel J, de Greef W, Hop W, Rowland D, Visser T . Effect of cold exposure on the hypothalamic release of thyrotropin-releasing hormone and catecholamines. Neuroendocrinology. 1991; 54(5):477-81. DOI: 10.1159/000125940. View

4.
Hefco E, KRULICH L, Illner P, Larsen P . Effect of acute exposure to cold on the activity of the hypothalamic-pituitary-thyroid system. Endocrinology. 1975; 97(5):1185-95. DOI: 10.1210/endo-97-5-1185. View

5.
Uribe R, Redondo J, Charli J, Joseph-Bravo P . Suckling and cold stress rapidly and transiently increase TRH mRNA in the paraventricular nucleus. Neuroendocrinology. 1993; 58(1):140-5. DOI: 10.1159/000126523. View