Bonaz Bruno, Sinniger Valérie, Pellissier Sonia
Division of Hepato-Gastroenterology, Grenoble University Hospital, Grenoble, Alpes, France.
U1216, INSERM, GIN, Grenoble Institute of Neurosciences, University Grenoble Alpes, Grenoble, France.
Front Immunol. 2017 Nov 2;8:1452. doi: 10.3389/fimmu.2017.01452. eCollection 2017.
The vagus nerve (VN) is the longest nerve of the organism and a major component of the parasympathetic nervous system which constitutes the autonomic nervous system (ANS), with the sympathetic nervous system. There is classically an equilibrium between the sympathetic and parasympathetic nervous systems which is responsible for the maintenance of homeostasis. An imbalance of the ANS is observed in various pathologic conditions. The VN, a mixed nerve with 4/5 afferent and 1/5 efferent fibers, is a key component of the neuro-immune and brain-gut axes through a bidirectional communication between the brain and the gastrointestinal (GI) tract. A dual anti-inflammatory role of the VN is observed using either vagal afferents, targeting the hypothalamic-pituitary-adrenal axis, or vagal efferents, targeting the cholinergic anti-inflammatory pathway. The sympathetic nervous system and the VN act in synergy, through the splenic nerve, to inhibit the release of tumor necrosis factor-alpha (TNFα) by macrophages of the peripheral tissues and the spleen. Because of its anti-inflammatory effect, the VN is a therapeutic target in the treatment of chronic inflammatory disorders where TNFα is a key component. In this review, we will focus on the anti-inflammatory role of the VN in inflammatory bowel diseases (IBD). The anti-inflammatory properties of the VN could be targeted pharmacologically, with enteral nutrition, by VN stimulation (VNS), with complementary medicines or by physical exercise. VNS is one of the alternative treatments for drug resistant epilepsy and depression and one might think that VNS could be used as a non-drug therapy to treat inflammatory disorders of the GI tract, such as IBD, irritable bowel syndrome, and postoperative ileus, which are all characterized by a blunted autonomic balance with a decreased vagal tone.
迷走神经（VN）是机体最长的神经，是构成自主神经系统（ANS）的副交感神经系统的主要组成部分，与交感神经系统共同作用。传统上，交感神经系统和副交感神经系统之间存在平衡，负责维持体内稳态。在各种病理状态下可观察到自主神经系统失衡。VN是一种混合神经，4/5为传入纤维，1/5为传出纤维，通过大脑与胃肠道（GI）之间的双向通信，是神经免疫轴和脑-肠轴的关键组成部分。使用迷走传入神经（靶向下丘脑-垂体-肾上腺轴）或迷走传出神经（靶向胆碱能抗炎途径），可观察到VN的双重抗炎作用。交感神经系统和VN通过脾神经协同作用，抑制外周组织和脾脏巨噬细胞释放肿瘤坏死因子-α（TNFα）。由于其抗炎作用，VN是治疗以TNFα为关键成分的慢性炎症性疾病的治疗靶点。在本综述中，我们将重点关注VN在炎症性肠病（IBD）中的抗炎作用。VN的抗炎特性可通过药理学方法、肠内营养、VN刺激（VNS）、补充药物或体育锻炼来靶向作用。VNS是耐药性癫痫和抑郁症的替代治疗方法之一，人们可能认为VNS可作为一种非药物疗法来治疗胃肠道炎症性疾病，如IBD、肠易激综合征和术后肠梗阻，这些疾病的共同特点是自主神经平衡减弱，迷走神经张力降低。
