Human brown adipose tissue [(15)O]O2 PET imaging in the presence and absence of cold stimulus.
Eur J Nucl Med Mol Imaging
; 43(10): 1878-86, 2016 Sep.
Article
em En
| MEDLINE
| ID: mdl-26993316
ABSTRACT
PURPOSE:
Brown adipose tissue (BAT) is considered a potential target for combatting obesity, as it produces heat instead of ATP in cellular respiration due to uncoupling protein-1 (UCP-1) in mitochondria. However, BAT-specific thermogenic capacity, in comparison to whole-body thermogenesis during cold stimulus, is still controversial. In our present study, we aimed to determine human BAT oxygen consumption with [(15)O]O2 positron emission tomography (PET) imaging. Further, we explored whether BAT-specific energy expenditure (EE) is associated with BAT blood flow, non-esterified fatty acid (NEFA) uptake, and whole-body EE.METHODS:
Seven healthy study subjects were studied at two different scanning sessions, 1) at room temperature (RT) and 2) with acute cold exposure. Radiotracers [(15)O]O2, [(15)O]H2O, and [(18)F]FTHA were given for the measurements of BAT oxygen consumption, blood flow, and NEFA uptake, respectively, with PET-CT. Indirect calorimetry was performed to assess differences in whole-body EE between RT and cold.RESULTS:
BAT-specific EE and oxygen consumption was higher during cold stimulus (approx. 50 %); similarly, whole-body EE was higher during cold stimulus (range 2-47 %). However, there was no association in BAT-specific EE and whole-body EE. BAT-specific EE was found to be a minor contributor in cold induced whole-body thermogenesis (almost 1 % of total whole-body elevation in EE). Certain deep muscles in the cervico-thoracic region made a major contribution to this cold-induced thermogenesis (CIT) without any visual signs or individual perception of shivering. Moreover, BAT-specific EE associated with BAT blood flow and NEFA uptake both at RT and during cold stimulus.CONCLUSION:
Our study suggests that BAT is a minor and deep muscles are a major contributor to CIT. In BAT, both in RT and during cold, cellular respiration is linked with circulatory NEFA uptake.Palavras-chave
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Consumo de Oxigênio
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Tecido Adiposo Marrom
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Termogênese
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Tomografia por Emissão de Pósitrons
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Resposta ao Choque Frio
Tipo de estudo:
Clinical_trials
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Diagnostic_studies
Limite:
Adult
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Female
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Humans
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Male
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article