NPD1 Relieves Neuropathic Pain and Accelerates the Recovery of Motor Function After Peripheral Nerve Injury.

The incidence of peripheral nerve injury (PNI) in China is continuously increasing. With an inability to function due to sensory and motor abnormalities, patients with PNI suffer from neuropathic pain and subsequent lesions. Presently, effective treatments for PNI are limited. To determine the role of neuroprotectin D1 (NPD1) in PNI, a sciatic nerve crush injury model was developed to investigate the impact of NPD1 on sensory and motor function recovery following nerve injury. The results demonstrated that NPD1 administered at different time points might reduce mechanical allodynia and thermal hyperalgesia caused by PNI, and its analgesic effect was not tolerated. Immunohistochemistry analyses revealed that administering NPD1 to PNI mice decreased the spinal microglia and astrocyte activation and decreased the inflammatory factor expression in the spinal dorsal horn. Furthermore, NPD1 can inhibit the invasion of IBA-1⁺ macrophages in dorsal root ganglions generated by nerve injury. Meanwhile, it can help rehabilitate motor and neuromuscular functions following PNI. The results indicate that NPD1 may be involved in the sensory and motor function recovery following PNI.