韩国科学技术院Gou Young Koh和美国密苏里大学Michael J. Davis团队合作的研究表明，鼻咽淋巴丛是脑脊液（CSF）引流的枢纽。2024年1月10日出版的《自然》杂志发表了这项成果。

在Prox1-GFP淋巴报告小鼠中使用荧光CSF示踪剂，研究人员发现鼻咽淋巴丛是CSF流向颈深淋巴结的主要枢纽。该淋巴丛具有特殊的瓣膜和短淋巴管，但没有平滑肌覆盖；而下游的颈深淋巴管具有典型的半月形瓣膜、长淋巴管和平滑肌覆盖，可将CSF输送到颈深淋巴结。平滑肌细胞中的α肾上腺素能和一氧化氮信号通过颈深淋巴管的运输特性调节CSF引流。

在衰老过程中，鼻咽淋巴丛萎缩，但颈深淋巴管并没有发生类似的变化，肾上腺素能或一氧化氮信号仍可增加CSF的流出。对老龄小鼠鼻咽神经丛淋巴内皮细胞基因表达的单细胞分析表明，I型干扰素信号和其他炎症细胞因子增加。鼻咽淋巴丛作为CSF流出枢纽的功能在衰老过程中出现退化。然而，抗衰老药物激活颈深淋巴管向淋巴结的转运仍能增加CSF的外流，这为年龄有关神经系统疾病提供了一种增加CSF清除的方法，在这些疾病中增加CSF的外流是有益的。

据悉，人们很早就知道大脑周围蛛网膜下腔的脑脊液会通过淋巴管引流到颈淋巴结，但其连接和调控的机制尚不可知。

附：英文原文

Title: Nasopharyngeal lymphatic plexus is a hub for cerebrospinal fluid drainage

Author: Yoon, Jin-Hui, Jin, Hokyung, Kim, Hae Jin, Hong, Seon Pyo, Yang, Myung Jin, Ahn, Ji Hoon, Kim, Young-Chan, Seo, Jincheol, Lee, Yongjeon, McDonald, Donald M., Davis, Michael J., Koh, Gou Young

Issue&Volume: 2024-01-10

Abstract: Cerebrospinal fluid (CSF) in the subarachnoid space around the brain has long been known to drain through the lymphatics to cervical lymph nodes1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17, but the connections and regulation have been challenging to identify. Here, using fluorescent CSF tracers in Prox1-GFP lymphatic reporter mice18, we found that the nasopharyngeal lymphatic plexus is a major hub for CSF outflow to deep cervical lymph nodes. This plexus had unusual valves and short lymphangions but no smooth-muscle coverage, whereas downstream deep cervical lymphatics had typical semilunar valves, long lymphangions and smooth muscle coverage that transported CSF to the deep cervical lymph nodes. α-Adrenergic and nitric oxide signalling in the smooth muscle cells regulated CSF drainage through the transport properties of deep cervical lymphatics. During ageing, the nasopharyngeal lymphatic plexus atrophied, but deep cervical lymphatics were not similarly altered, and CSF outflow could still be increased by adrenergic or nitric oxide signalling. Single-cell analysis of gene expression in lymphatic endothelial cells of the nasopharyngeal plexus of aged mice revealed increased type I interferon signalling and other inflammatory cytokines. The importance of evidence for the nasopharyngeal lymphatic plexus functioning as a CSF outflow hub is highlighted by its regression during ageing. Yet, the ageing-resistant pharmacological activation of deep cervical lymphatic transport towards lymph nodes can still increase CSF outflow, offering an approach for augmenting CSF clearance in age-related neurological conditions in which greater efflux would be beneficial.

DOI: 10.1038/s41586-023-06899-4

Source: https://www.nature.com/articles/s41586-023-06899-4