Efferent signals from the central nervous system represent a key layer of regulation of white adipose tissue (WAT). However, the mechanism by which efferent neural signals control WAT metabolism remains to be better understood. Here, we exploit the volume fluorescence-imaging technique to visualize the neural arborizations in mouse inguinal WAT at single-fiber resolution. The imaging reveals a dense network of sympathetic arborizations that had been previously undetected by conventional methods, with sympathetic fibers being in close apposition to > 90% of adipocytes. We demonstrate that these sympathetic fibers originate from the celiac ganglia, which are activated by cold challenge. Sympathetic-specific deletion of TrkA receptor or pharmacologic ablation by 6-hydroxydopamine abolishes these intra-adipose arborizations and, as a result, cold-induced beiging of inguinal WAT. Furthermore, we find that local sympathetic arborizations function through beta-adrenergic receptors in this beiging process. These findings uncover an essential link connecting efferent neural signals with metabolism of individual adipocytes.

中文翻译：

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密集的脂肪内交感乔木对于小鼠白脂肪组织的冷诱导米色形成必不可少

来自中枢神经系统的传出信号代表了白色脂肪组织（WAT）调节的关键层。但是，传出的神经信号控制WAT代谢的机制仍有待更好地理解。在这里，我们利用体荧光成像技术以单纤维分辨率可视化小鼠腹股沟WAT中的神经乔化。成像显示，交感神经交织的密集网络以前无法通过常规方法检测到，交感神经纤维与> 90％的脂肪细胞紧密并置。我们证明这些交感神经纤维来自腹腔神经节，由冷挑战激活。TrkA受体的交感特异性删除或6-羟基多巴胺的药理消融消除了这些脂肪内的乔木化，因此，腹股沟WAT的冷诱发。此外，我们发现，在这个起伏过程中，局部交感乔木通过β-肾上腺素受体起作用。这些发现揭示了将传出的神经信号与单个脂肪细胞的代谢联系起来的重要联系。