Abstract:Neuropathic pain (NP) is a chronic pain condition caused by a lesion or disease of the somatosensory nervous system. It is characterized by complex etiologies, a prolonged disease course, limited responsiveness to conventional pharmacological treatments, and frequent comorbid emotional and sleep disturbances, and remains a formidable clinical challenge. As the primary integration hub for peripheral nociceptive input, the spinal cord plays a critical role in the transmission and modulation of pain signals, while maladaptive synaptic plasticity is increasingly recognized as a key pathological mechanism underlying the initiation and maintenance of NP. Accumulating evidence indicates that acupuncture, as a safe and effective non-pharmacological analgesic intervention, can alleviate NP through multiple mechanisms, including modulation of synaptic ultrastructure, synaptic transmission efficacy, glial cell activation, the synaptic microenvironment, and pain-related gene expression. However, the available evidence remains fragmented, lacking a systematic synthesis. Therefore, centering on spinal synaptic plasticity, this review systematically summarizes its role in NP and recent advances in acupuncture therapies across four dimensions: structural and functional synaptic plasticity, glia-neuron crosstalk, the synaptic microenvironment, and epigenetic regulation. We further discuss current research gaps and future directions in this field, with the aim of elucidating the neurobiological mechanisms underlying acupuncture analgesia and providing insights for future studies on specific therapeutic targets and individualized treatment strategies.
