Neuropilin-1 Is Essential For VEGFA-Mediated Increase Of Sensory Neuron Activity And Development Of Pain-Like Behaviors

Neuropilin-1 (NRP-1) is a transmembrane glycoprotein that binds numerous ligands including vascular endothelial growth factor A (VEGFA). Binding of this ligand to NRP-1 and the co-receptor, the tyrosine kinase receptor VEGFR2, elicits nociceptor sensitization resulting in pain via enhancement of the activity of voltage-gated sodium and calcium channels. We previously reported that blocking the interaction between VEGFA and NRP-1 with either the small molecule inhibitor EG00229 or the Spike protein of SARS-CoV-2 attenuates VEGFA-induced dorsal root ganglion (DRG) neuronal excitability and alleviates neuropathic pain, pointing to the VEGFA/NRP-1 signaling as a novel therapeutic target of pain. Here, using electrophysiology and pain models, we investigated whether peripheral sensory neurons and spinal cord hyperexcitability and pain behaviors were affected by the loss of NRP-1. A CRIPSR/Cas9 strategy targeting the second exon of nrp-1 gene was employed to knockdown NRP-1. NRP-1 editing in DRG neurons reduced VEGFA-mediated increases in CaV2.2 currents and sodium currents through NaV1.7. NRP-1 editing had no impact on voltage-gated potassium channels. Following in vivo editing of NRP-1, lumbar dorsal horn slices showed a decrease in the frequency of VEGFA-mediated increases in spontaneous excitatory postsynaptic currents. Finally, intrathecal injection of a lentivirus packaged with an NRP-1 guide RNA and Cas9 enzyme prevented VEGFA-induced mechanical allodynia and thermal hyperalgesia in both male and female mice. Collectively, our findings highlight a key role of NRP-1 in modulating pain pathways in the sensory nervous system. This study was supported by National Institutes of Health awards (NS098772, NS120663, NS122545, and DA042852 to Rajesh Khanna).

SARS-CoV-2 spike protein co-opts VEGF-A/neuropilin-1 receptor signaling to induce analgesia.

Global spread of severe acute respiratory syndrome coronavirus 2 continues unabated. Binding of severe acute respiratory syndrome coronavirus 2's spike protein to host angiotensin-converting enzyme 2 triggers viral entry, but other proteins may participate, including the neuropilin-1 receptor (NRP-1). Because both spike protein and vascular endothelial growth factor-A (VEGF-A)-a pronociceptive and angiogenic factor, bind NRP-1, we tested whether spike could block VEGF-A/NRP-1 signaling. VEGF-A-triggered sensory neuron firing was blocked by spike protein and NRP-1 inhibitor EG00229. Pronociceptive behaviors of VEGF-A were similarly blocked through suppression of spontaneous spinal synaptic activity and reduction of electrogenic currents in sensory neurons. Remarkably, preventing VEGF-A/NRP-1 signaling was antiallodynic in a neuropathic pain model. A "silencing" of pain through subversion of VEGF-A/NRP-1 signaling may underlie increased disease transmission in asymptomatic individuals.