Combined use of Bumetanide and MGE cell transplantation alleviates neuropathic pain and its mechanism after spinal cord injury in mice.

INTRODUCTION: Neuropathic pain (NP) after spinal cord injury (SCI) is intractable with limited efficacy of single treatments. This study investigated the additive analgesic effect and molecular mechanisms of Bumetanide (Bu, a NKCC1 inhibitor) combined with medial ganglionic eminence (MGE) cell transplantation on SCI-induced NP. METHODS: Ninety adult female C57BL/6N mice were randomly divided into 5 groups (Sham, SCI, Bu, Mge, Bu+Mge). A T10 moderate spinal cord contusion model was established, with treatments (Bu intraperitoneal injection and MGE orthotopic transplantation) on day 10 post-surgery. Behavioral assessments, ELISA, Western blotting, qRT-PCR, and immunofluorescence staining were used. RESULTS: Compared with monotherapy, Bu+Mge significantly relieved SCI-induced NP. Mechanistically, it alleviated inflammation by inhibiting NF-κB pathway and microglia activation, rectified spinal cord and dorsal root ganglion NKCC1/KCC2 imbalance, increased GABA-A receptors and GAD65/67 mRNA, reduced glial scarring, and protected neurons, axons and myelin sheaths. DISCUSSION: Bu combined with MGE cell transplantation relieves SCI-induced NP via multiple additive mechanisms, providing a novel theoretical basis and potential clinical strategy for NP treatment.