Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland.
Nat Cell Biol. 2013 Jun;15(6):659-67. doi: 10.1038/ncb2740. Epub 2013 Apr 28.
Brown adipose tissue helps to maintain body temperature in hibernators, rodents and neonatal mammals by converting lipids and glucose into heat, thereby increasing energy expenditure. In addition to classical brown adipocytes, adult rodents-like adult humans-harbour brown-like adipocytes in the predominantly white adipose tissue. The formation of these brite (brown-in-white) adipocytes is a physiological response to chronic cold and their cellular origin is under debate. We show here that cold-induced formation of brite adipocytes in mice is reversed within 5 weeks of warm adaptation, but the brite adipocytes formed by cold stimulation are not eliminated. Genetic tracing and transcriptional characterization of isolated adipocytes demonstrates that they are converted into cells with the morphology and gene expression pattern of white adipocytes. Moreover, these white-typical adipocytes can convert into brite adipocytes on additional cold stimulation. Shifting the balance of this interconversion from the white towards the brite phenotype might provide a new means of counteracting obesity by increasing energy expenditure.
棕色脂肪组织通过将脂质和葡萄糖转化为热量来帮助冬眠动物、啮齿动物和新生哺乳动物维持体温，从而增加能量消耗。除了经典的棕色脂肪细胞外，成年啮齿动物——像成年人类一样——在主要的白色脂肪组织中也存在棕色样脂肪细胞。这些 brite（白色中的棕色）脂肪细胞的形成是对慢性寒冷的生理反应，其细胞起源仍存在争议。我们在这里表明，在温暖适应的 5 周内，小鼠体内冷诱导的 brite 脂肪细胞的形成会逆转，但冷刺激形成的 brite 脂肪细胞不会被消除。对分离的脂肪细胞进行遗传追踪和转录特征分析表明，它们转化为具有白色脂肪细胞形态和基因表达模式的细胞。此外，这些白色典型脂肪细胞在再次受到冷刺激时可以转化为 brite 脂肪细胞。增加能量消耗以增加白色向 brite 表型的这种相互转化的平衡，可能为对抗肥胖提供一种新的手段。
