Brown adipose tissue (BAT) activation is a possible therapeutic strategy to increase energy expenditure and improve metabolic homeostasis in obesity. Recent studies have revealed novel interactions between BAT and circulating lipid species—in particular, the non-esterified fatty acid (NEFA) and oxylipin lipid classes. This study aimed to identify individual lipid species that may be associated with cold-stimulated BAT activity in humans. A panel of 44 NEFA and 41 oxylipin species were measured using mass-spectrometry-based lipidomics in the plasma of fourteen healthy male participants before and after 90 min of mild cold exposure. Lipid measures were correlated with BAT activity measured via ¹⁸F-fluorodeoxyglucose ([¹⁸F]FDG) positron emission tomography/computed tomography (PET/CT), along with norepinephrine (NE) concentration (a surrogate marker of sympathetic activity). The study identified a significant increase in total NEFA concentration following cold exposure that was positively associated with NE concentration change. Individually, 33 NEFA and 11 oxylipin species increased significantly in response to cold exposure. The concentration of the omega-3 NEFA, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) at baseline was significantly associated with BAT activity, and the cold-induced change in 18 NEFA species was significantly associated with BAT activity. No significant associations were identified between BAT activity and oxylipins.

中文翻译：

---

血浆二十二碳六烯酸和二十碳五烯酸浓度与人类的棕色脂肪组织活性成正相关

棕色脂肪组织（BAT）的激活是一种可能的治疗策略，可以增加能量消耗并改善肥胖者的代谢稳态。最近的研究表明，BAT与循环脂质种类之间存在新颖的相互作用，特别是非酯化脂肪酸（NEFA）和脂蛋白脂质类别。这项研究旨在确定可能与人类冷刺激的BAT活性有关的单个脂质物种。在轻度冷暴露90分钟之前和之后，使用基于质谱的脂质组学技术在14名健康男性参与者的血浆中测量了44种NEFA和41种脂蛋白。脂质测量与通过¹⁸ F-氟代脱氧葡萄糖测量的BAT活性相关（[ ¹⁸F] FDG）正电子发射断层扫描/计算机断层扫描（PET / CT），以及去甲肾上腺素（NE）浓度（交感神经活动的替代标志物）。研究发现冷暴露后总NEFA浓度显着增加，与NE浓度变化呈正相关。单独地，响应于冷暴露，33种NEFA和11种脂族物质显着增加。基线时，omega-3 NEFA，二十二碳六烯酸（DHA）和二十碳五烯酸（EPA）的浓度与BAT活性显着相关，而18种NEFA物种的冷诱导变化与BAT活性显着相关。在BAT活性和脂蛋白之间没有发现明显的关联。