美国麻省大学Mark J. Alkema研究组发现，肠道细菌产生的维生素B12可调节胆碱能信号传导。该项研究成果于2024年1月2日在线发表在《自然—细胞生物学》杂志上。

研究人员发现肠道中产生维生素B12的细菌可以调节宿主秀丽隐杆线虫的兴奋性胆碱能信号传导和行为。研究人员证明，维生素B12可通过重新连接肠道中的蛋氨酸（Met）/S-腺苷蛋氨酸循环，减少神经系统中的胆碱能信号。研究人员发现蛋氨酸/S-腺苷蛋氨酸循环与胆碱氧化途径之间存在保守的代谢交流。

此外，研究人员还发现维生素B12对这些途径的代谢重构限制了神经元合成乙酰胆碱所需的游离胆碱，从而降低了胆碱能信号的传递。这项研究揭示了肠道细菌调节宿主行为并可能影响神经系统健康的肠脑交流途径。

据了解，越来越多的证据表明，肠道微生物群会影响大脑功能和行为。然而，肠道细菌如何调节宿主神经系统功能的分子基础在很大程度上还不为人所知。

附：英文原文

Title: Vitamin B12 produced by gut bacteria modulates cholinergic signalling

Author: Kang, Woo Kyu, Florman, Jeremy T., Araya, Antonia, Fox, Bennett W., Thackeray, Andrea, Schroeder, Frank C., Walhout, Albertha J. M., Alkema, Mark J.

Issue&Volume: 2024-01-02

Abstract: A growing body of evidence indicates that gut microbiota influence brain function and behaviour. However, the molecular basis of how gut bacteria modulate host nervous system function is largely unknown. Here we show that vitamin B12-producing bacteria that colonize the intestine can modulate excitatory cholinergic signalling and behaviour in the host Caenorhabditis elegans. Here we demonstrate that vitamin B12 reduces cholinergic signalling in the nervous system through rewiring of the methionine (Met)/S-adenosylmethionine cycle in the intestine. We identify a conserved metabolic crosstalk between the methionine/S-adenosylmethionine cycle and the choline-oxidation pathway. In addition, we show that metabolic rewiring of these pathways by vitamin B12 reduces cholinergic signalling by limiting the availability of free choline required by neurons to synthesize acetylcholine. Our study reveals a gut–brain communication pathway by which enteric bacteria modulate host behaviour and may affect neurological health.

DOI: 10.1038/s41556-023-01299-2

Source: https://www.nature.com/articles/s41556-023-01299-2