Increased H19 Long Non-coding RNA Expression in Schwann Cells in Peripheral Neuropathic Pain

Background: Neuropathic pain is an intractable chronic pain condition caused by damage to the somatosensory system. Although non-coding RNAs such as microRNAs are important regulators of neuropathic pain, the role of long non-coding RNAs (lncRNAs) is poorly understood. Methods: This study used a rat model of neuropathic pain induced by lumbar fifth spinal nerve ligation (SNL). Microarray analysis of lncRNAs in the lumbar fifth dorsal root ganglion was performed at day 14 after SNL. Expression levels of H19 were examined by using quantitative PCR. In situ hybridization was used to determine the distribution of H19 at day 14 after SNL. Schwann cells were isolated from peripheral nerves at day 14 after SNL. Results: H19 lncRNA was greatly increased in the L5 dorsal root ganglion at day 14 after SNL and was significantly higher at and after day 4. In the dorsal root ganglion, H19 was detected mainly in non neuronal cells but not in primary sensory neurons. Consistent with this, H19 expression was upregulated in Schwann cells isolated from peripheral nerves after SNL. Conclusion: Increased H19 lncRNA in Schwann cells might be involved in neuropathic pain.