TET1 Overexpression Mitigates Neuropathic Pain Through Rescuing the Expression of μ-Opioid Receptor and Kv1.2 in the Primary Sensory Neurons

  • Qiang Wu
  • Guihua Wei
  • Fengtao Ji
  • Shushan Jia
  • Shaogen Wu
  • Xinying Guo
  • Long He
  • Zhiqiang Pan
  • Xuerong Miao
  • Qingxiang Mao
  • Yong Yang
  • Minghui CaoEmail author
  • Yuan-Xiang TaoEmail author
Original Article


Peripheral nerve injury downregulates the expression of the μ-opioid receptor (MOR) and voltage-gated potassium channel subunit Kv1.2 by increasing their DNA methylation in the dorsal root ganglion (DRG). Ten-eleven translocation methylcytosine dioxygenase 1 (TET1) causes DNA demethylation. Given that DRG MOR and Kv1.2 downregulation contribute to neuropathic pain genesis, this study investigated the effect of DRG TET1 overexpression on neuropathic pain. Overexpression of TET1 in the DRG through microinjection of herpes simplex virus expressing full-length TET1 mRNA into the injured rat DRG significantly alleviated the fifth lumbar spinal nerve ligation (SNL)–induced pain hypersensitivities during the development and maintenance periods, without altering acute pain or locomotor function. This microinjection also restored morphine analgesia and attenuated morphine analgesic tolerance development after SNL. Mechanistically, TET1 microinjection rescued the expression of MOR and Kv1.2 by reducing the level of 5-methylcytosine and increasing the level of 5-hydroxymethylcytosine in the promoter and 5′ untranslated regions of the Oprml1 gene (encoding MOR) and in the promoter region of the Kcna2 gene (encoding Kv1.2) in the DRG ipsilateral to SNL. These findings suggest that DRG TET1 overexpression mitigated neuropathic pain likely through rescue of MOR and Kv1.2 expression in the ipsilateral DRG. Virus-mediated DRG delivery of TET1 may open a new avenue for neuropathic pain management.


TET1 DNA demethylation μ-opioid receptor Kv1.2 dorsal root ganglion neuropathic pain 



We appreciate Dr. Wanhong Zuo for the single-cell collection and acknowledge Ms. Jamie Bono for the assistance in the preparation of the manuscript. This work was supported by NIH grants (R01NS094664, R01NS094224, and R01DA033390) for YXT, the National Nature Science Foundation of China (81471352) for MC, and the Fundamental Research Funds for the Central Universities (2682016CX103) for GW.

Authors’ Contributions

Y.X.T. and M.C. conceived the project and supervised all experiments. Q.W., G.W., F.J., S.J., and Y.X.T. designed the project. Q.W., F.J., X.G., X.M., and S.J. performed the animal model, conducted behavioral experiments, and carried out microinjection and DRG culture. G.W., X.G., L.H., and F.J. carried out Western blot, chromatin immunoprecipitation, and PCR experiments. Z.P., Y.Y., and Q.M. helped with Western blot and chromatin immunoprecipitation experiments. S.W. constructed HSV-TET1 and carried out PCR. Q.W., S.J., M.C., and Y.X.T. analyzed the data. Q.W., M.C., and Y.X.T. wrote the manuscript. All of the authors read and discussed the manuscript.

Compliance with Ethical Standards

All procedures used were approved by the Animal Care and Use Committee at the Rutgers New Jersey Medical School (Newark, New Jersey).

Competing Interests

The authors declare that they have no conflict of interest.


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Copyright information

© The American Society for Experimental NeuroTherapeutics, Inc. 2018

Authors and Affiliations

  • Qiang Wu
    • 1
    • 2
  • Guihua Wei
    • 1
    • 3
  • Fengtao Ji
    • 1
    • 2
  • Shushan Jia
    • 1
    • 4
  • Shaogen Wu
    • 1
  • Xinying Guo
    • 1
  • Long He
    • 1
  • Zhiqiang Pan
    • 1
  • Xuerong Miao
    • 1
  • Qingxiang Mao
    • 1
  • Yong Yang
    • 1
  • Minghui Cao
    • 2
    Email author
  • Yuan-Xiang Tao
    • 1
    Email author
  1. 1.Department of Anesthesiology, New Jersey Medical School, RutgersThe State University of New JerseyNewarkUSA
  2. 2.Department of Anesthesiology, Sun Yat-Sen Memorial HospitalSun Yat-Sen UniversityGuangzhouChina
  3. 3.Department of Pharmacy, Institute of Life Science and EngineeringSouthwest Jiaotong UniversityChengduChina
  4. 4.Department of AnesthesiologyYantai Affiliated Hospital of Binzhou Medical UniversityYantaiChina

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