Spinal signatures of entrenched and treated neuropathic pain

Chronic pain arises from an imbalance between excitation and inhibition. For chronic pain caused by peripheral nerve injury, sensory neuron damage leads to changes in spinal pain transduction, where enhanced excitatory and/or loss of inhibitory pathways can drive pain diseases. At the cellular level, the transcriptional changes occurring in entrenched chronic pain are largely unknown. Here we use single nuclei and spatial transcriptomic approaches to investigate the cellular and molecular causes of entrenched and treated neuropathic pain. Our data rules out a loss of spinal inhibitor neuron populations or transcriptional downregulation of inhibitory machinery, and instead we show that nerve injury leads to broad upregulation of spinal synaptic and excitatory pathways in dorsal neuronal and glial populations. We confirm these core populations are conserved in the human spinal cord, and show an effective pain therapy acts by dampening these neuropathic transcriptional programs. Overall, our data provides the first high resolution transcriptional analysis of the neuropathic spinal cord, highlighting known and novel pathways that may help us better manage pain diseases.