Continuous cold exposure induces an anti-inflammatory response in mesenteric adipose tissue associated with catecholamine production and thermogenin expression in rats.
Endocr Regul
; 50(3): 137-44, 2016 Jul.
Article
em En
| MEDLINE
| ID: mdl-27560796
ABSTRACT
OBJECTIVE:
Continuous exposure to cold leads to an activation of adaptive thermogenesis in the brown adipose tissue and induction of brown/beige cell phenotype in the white adipose tissue. Thermogenic response is associated with alternatively activated macrophages producing catecholamines, which subsequently activate the uncoupling protein 1 (UCP-1). The aim of this work was to elucidate the effect of cold exposure on catecholamine and immune responses associated with adipocyte browning in the mesenteric adipose tissue (mWAT) of rat.METHODS:
The rats were exposed to continuous cold (4 °C) for 1 or 7 days. Catecholamines production and gene expressions of inflammatory and other factors, related to adipocyte "browning", were analyzed in the homogenized mWAT samples using 2-CAT ELISA kits.RESULTS:
Cold exposure induced a sympathetic response in the mWAT, evidenced by the tyrosine hydroxylase (TH) protein level rise. Induction of non-sympathetical catecholamine production was observed 7 days after cold exposure by elevated TH and phenylethanolamine-N-methyltransferase (PNMT) expression, leading to an increased epinephrine levels. Cold exposure for 7 days stimulated the infiltration of macrophages, evaluated by F4/80 and CD68 expressions, and expression of anti-inflammatory mediators, while pro-inflammatory cytokines were inhibited. Anti- inflammatory response, accompanied by de novo catecholamine production and up-regulation of ß3-adrenergic receptors, led to the stimulation of UCP-1 and PGC1α expression, suggesting a cold-induced "browning" of the mWAT, mediated by alternatively activated macrophages.CONCLUSIONS:
The present data indicate that prolonged cold exposure may induce anti-inflammatory response in mWAT associated with induction of UCP-1 expression. Although functional thermogenesis in the mWAT is most likely redundant, a highly efficient dissipation of energy by UCP1 may affect the energy homeostasis in this visceral fat.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Catecolaminas
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Citocinas
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Temperatura Baixa
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Mediadores da Inflamação
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Termogênese
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Gordura Intra-Abdominal
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Tecido Adiposo Bege
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Proteína Desacopladora 1
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Hipotermia
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Inflamação
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article