Robinson Lindsay J, Law James M, Symonds Michael E, Budge Helen
The Early Life Research Unit, Division of Child Health, Obstetrics and Gynaecology, School of Medicine, University Hospital, University of Nottingham, Nottingham, NG7 2UH, UK.
Exp Physiol. 2016 Apr;101(4):549-57. doi: 10.1113/EP085642. Epub 2016 Feb 18.
What is the central question of this study? Does psychological stress, which is known to promote cortisol secretion, simultaneously activate brown adipose tissue function in healthy adult females? What is the main finding and its importance? One explanation for the pronounced differences in brown adipose tissue function between individuals lies in their responsiveness to psychological stress and, as such, should be taken into account when examining its in vivo stimulation. Brown adipose tissue (BAT) has been implicated in the pathogenesis of obesity, type 2 diabetes and the metabolic syndrome and is a potential therapeutic target. Brown adipose tissue can have a significant impact on energy balance and glucose homeostasis through the action of uncoupling protein 1, dissipating chemical energy as heat following neuroendocrine stimulation. We hypothesized that psychological stress, which is known to promote cortisol secretion, would simultaneously activate BAT at thermoneutrality. Brown adipose tissue activity was measured using infrared thermography to determine changes in the temperature of the skin overlying supraclavicular BAT (TSCR ). A mild psychological stress was induced in five healthy, lean, female, Caucasian volunteers using a short mental arithmetic (MA) test. The TSCR was compared with a repeated assessment, in which the MA test was replaced with a period of relaxation. Although MA did not elicit an acute stress response, anticipation of MA testing led to an increase in salivary cortisol, indicative of an anticipatory stress response, that was associated with a trend towards higher absolute and relative TSCR . A positive correlation between TSCR and cortisol was found during the anticipatory phase, a relationship that was enhanced by increased cortisol linked to MA. Our findings suggest that subtle changes in the level of psychological stress can stimulate BAT, findings that may account for the high variability and inconsistency in reported BAT prevalence and activity measured by other modalities. Consistent assessment of this uniquely metabolic tissue is fundamental to the discovery of potential therapeutic strategies against metabolic disease.
本研究的核心问题是什么？已知会促进皮质醇分泌的心理压力，是否会同时激活健康成年女性的棕色脂肪组织功能？主要发现及其重要性是什么？个体之间棕色脂肪组织功能存在显著差异的一种解释在于其对心理压力的反应性，因此，在研究其体内刺激时应予以考虑。棕色脂肪组织（BAT）与肥胖症、2型糖尿病和代谢综合征的发病机制有关，是一个潜在的治疗靶点。棕色脂肪组织可通过解偶联蛋白1的作用对能量平衡和葡萄糖稳态产生重大影响，在神经内分泌刺激后将化学能以热量形式散发。我们假设，已知会促进皮质醇分泌的心理压力会在热中性条件下同时激活棕色脂肪组织。使用红外热成像测量棕色脂肪组织活性，以确定锁骨上棕色脂肪组织上方皮肤温度（TSCR）的变化。对五名健康、瘦体型、高加索女性志愿者进行简短心算（MA）测试，诱导轻度心理压力。将TSCR与重复评估结果进行比较，在重复评估中用一段放松期取代MA测试。虽然MA并未引发急性应激反应，但对MA测试的预期导致唾液皮质醇增加，表明存在预期应激反应，这与TSCR绝对值和相对值升高的趋势相关。在预期阶段发现TSCR与皮质醇之间存在正相关，MA导致皮质醇增加增强了这种关系。我们的研究结果表明，心理压力水平的细微变化可刺激棕色脂肪组织，这一发现可能解释了其他方法测量的棕色脂肪组织患病率和活性报告中存在的高变异性和不一致性。对这种独特的代谢组织进行一致评估是发现针对代谢疾病潜在治疗策略的基础。
