1)北京生命科技研究院,北京 102200;2)国家烟草质量监督检验中心,郑州 450001
北京生命科技研究院青年人才项目(2025100CC0030),河南省青年基金(242300420447)和PI项目(2024501QPIC05,2024102QPID06)资助。
1)Beijing Life Science Academy, Beijing 102200, China;2)China National Tobacco Quality Supervision & Test Center, Zhengzhou 450001, China
This work was supported by grants from the Young Talent Program of Beijing Life Science Academy (2025100CC0030), the Youth Foundation of Henan Province (242300420447), and PI Projects (2024501QPIC05, 2024102QPID06).
α7烟碱型乙酰胆碱受体(α7 nicotinic acetylcholine receptor,α7 nAChR)是一种具有高Ca2+通透性、快速激活和快速脱敏特征的配体门控离子通道,广泛参与神经兴奋性调节、突触传递与可塑性、神经保护及胆碱能抗炎反应,是多种神经精神疾病和炎症性疾病的潜在治疗靶点。近年来,冷冻电镜等技术的发展推动了对α7 nAChR门控循环、配体识别和变构调节机制的解析,为靶向该受体的药物设计提供新的结构基础。目前,靶向α7 nAChR的药物研发主要集中于正构激动剂(orthosteric agonists),正变构调节剂(positive allosteric modulators,PAMs)以及兼具直接变构激活与变构调节作用的变构激动剂(allosteric agonist-positive allosteric modulators,ago-PAMs)。其中,正构激动剂是较早开展临床研究的α7 nAChR配体类型,但受体固有的快速脱敏以及药物疗效稳定性不足等因素仍限制其临床转化、PAMs和ago-PAMs通过变构调节或变构激活对受体功能进行精细调控,为提高亚型选择性、调控受体动力学及拓展药物设计策略提供了新的方向。本文围绕α7 nAChR的结构特征、生理功能、疾病关联及药理学研究进展进行综述,系统梳理其正构激动剂、PAMs和ago-PAMs的作用特点与研发进展,并讨论靶向α7 nAChR药物临床转化面临的挑战与未来药物设计方向。
The α7 nicotinic acetylcholine receptor (α7 nAChR) is a ligand-gated ion channel characterized by high Ca2+ permeability, rapid activation, and rapid desensitization. It is widely expressed in the nervous system and various non-neuronal cell types. α7 nAChR is involved in regulating neuronal excitability, synaptic transmission and plasticity, cognitive function, and inflammatory responses. These properties have made α7 nAChR a potential therapeutic target for neuropsychiatric and inflammatory diseases. In recent years, advances in cryo-electron microscopy have provided structural insights into α7 nAChR gating, ligand recognition, allosteric modulation, and allosteric activation. The receptor mainly undergoes transitions among resting, open, and desensitized states. Recent structural studies have further revealed asymmetric conformational changes and multiple intermediate states during receptor activation and recovery from desensitization. Conformational rearrangements in the extracellular domain-transmembrane domain coupling region and the pore-forming M2 helices are closely associated with channel opening and desensitization. However, structural characterization of the α7 nAChR gating cycle still largely depends on pharmacological stabilization. Open-state structures have been resolved in the presence of PNU-120596 or GAT107, whereas a high-resolution structure of the open state induced by acetylcholine alone remains to be determined. These physiological roles underpin the involvement of α7 nAChR in multiple disease processes. In the hippocampus, α7 nAChR regulates local neuronal circuits, theta oscillations, synaptic transmission, and synaptic plasticity, thereby contributing to learning, memory, attention, and other cognitive processes. In macrophages, microglia, and other immune-related cells, α7 nAChR activation regulates inflammatory responses and oxidative stress. These effects involve several signaling pathways, including Janus kinase 2 (JAK2)/STAT3, phosphoinositide 3-kinase (PI3K)/AKT, and NF-κB signaling, as well as regulation of the NLRP3 inflammasome and IL-1β production. Such anti-inflammatory effects may also contribute to α7 nAChR-mediated neuroprotection. Although several compounds targeting α7 nAChR have entered clinical studies, no α7 nAChR-selective drug has been approved for clinical use. Limited clinical translation may be related to rapid receptor desensitization, inconsistent efficacy across clinical studies, insufficient or variable target engagement, patient heterogeneity, and clinical endpoint selection. TC-5619 showed promising effects on cognitive impairment and negative symptoms in an early exploratory study of schizophrenia, but these effects were not confirmed in a subsequent, larger phase II trial. Encenicline (EVP-6124) also showed cognitive improvement in early studies, whereas two global phase III trials in schizophrenia failed to meet their co-primary cognitive and functional endpoints. Pharmacological strategies targeting α7 nAChR have expanded from orthosteric agonists to positive allosteric modulators (PAMs) and allosteric agonist-positive allosteric modulators (ago-PAMs). Orthosteric agonists directly activate the receptor by binding to the orthosteric site, but their effects are limited by rapid receptor desensitization. Type I PAMs mainly enhance agonist-evoked responses with relatively small effects on desensitization, whereas type II PAMs markedly potentiate receptor responses and reduce or delay desensitization. Ago-PAMs such as GAT107 can directly activate α7 nAChR through an allosteric mechanism while also potentiating responses to orthosteric agonists. Together, these findings have broadened the pharmacological approaches to α7 nAChR regulation. In summary, future drug development should focus on precise regulation of α7 nAChR according to receptor structure and disease mechanisms, rather than simply enhancing receptor activation. Further studies are needed to clarify how candidate ligands affect receptor gating, conformational transitions, recovery from desensitization, and downstream signaling. Pharmacological differences between neuronal and non-neuronal α7 nAChRs, between homomeric α7 and heteromeric α7β2 receptors, and between α7 nAChR and other nAChR subtypes also require further investigation. Integrating structure prediction, artificial intelligence-assisted virtual screening, molecular docking, molecular dynamics simulations, and electrophysiological validation may facilitate the discovery and optimization of new α7 nAChR modulators.
刘雨涵,陈姣凤,王红娟,陈欢,侯宏卫.α7烟碱型乙酰胆碱受体:从结构机制到药物转化[J].生物化学与生物物理进展,2026,53(9):2378-2391 LIU Yu-Han, CHEN Jiao-Feng, WANG Hong-Juan, CHEN Huan, HOU Hong-Wei.α7 Nicotinic Acetylcholine Receptor: From Structural Mechanisms to Therapeutic Translation[J]. Progress in Biochemistry and Biophysics,2026,53(9):2378-2391
复制

扫码关注 生物化学与生物物理进展 ® 2026 网站版权 ICP:京ICP备05023138号-1 京公网安备 11010502031771号
