Dinan Timothy G, Butler Mary I, Cryan John F
Department of Psychiatry, APC Microbiome Ireland, University College Cork, Cork, Ireland.
Department of Anatomy and Neuroscience, APC Microbiome Ireland, University College Cork, Cork, Ireland.
Mod Trends Psychiatry. 2021;32:134-143. doi: 10.1159/000510424. Epub 2021 May 6.
The gut-brain axis is a bidirectional communication system which allows the central nervous system and gastrointestinal tract to interact with and respond to each other rapidly and effectively. It is becoming increasingly clear that major players in this complex system are gut bacteria. The mechanisms of signal transmission from bacteria to the brain are complex and not fully elucidated, but include neural, endocrine, immune, and metabolic pathways. It was initially demonstrated in a rodent model of depression that the gut microbiota was altered. This observation has been replicated in patients with major depression who show decreased microbial diversity. Furthermore, when rodents receive a microbiota transplant from a depressed patient their behaviour alters, as does their tryptophan metabolism and immune status. Several studies of psychobiotics (bacteria with a potential mental health benefit) have been conducted in healthy populations and in patients with depression. While some psychobiotics have shown efficacy in treating depression, other bacteria have yielded negative findings. Larger-scale, well-designed studies are required. EU-funded guidelines recommend that patients with depression or vulnerability to depression should be encouraged to enhance a plant-based diet with a high content of grains/fibres, fermented foods, and fish. A significant impact of such a diet is likely mediated through the gut microbiota.
肠-脑轴是一个双向通信系统，它使中枢神经系统和胃肠道能够快速、有效地相互作用并做出反应。越来越清楚的是，这个复杂系统中的主要参与者是肠道细菌。从细菌到大脑的信号传递机制很复杂，尚未完全阐明，但包括神经、内分泌、免疫和代谢途径。最初在抑郁症的啮齿动物模型中证明肠道微生物群发生了改变。这一观察结果在患有重度抑郁症且微生物多样性降低的患者中得到了重复验证。此外，当啮齿动物接受来自抑郁症患者的微生物群移植时，它们的行为会发生改变，色氨酸代谢和免疫状态也会改变。已经在健康人群和抑郁症患者中进行了几项关于精神益生菌（对心理健康有潜在益处的细菌）的研究。虽然一些精神益生菌已显示出治疗抑郁症的疗效，但其他细菌的研究结果为阴性。需要开展更大规模、设计良好的研究。欧盟资助的指南建议，应鼓励患有抑郁症或有抑郁症易感性的患者增加以谷物/纤维、发酵食品和鱼类含量高的植物性饮食。这种饮食的显著影响可能是通过肠道微生物群介导的。
