Spinal astrocytic activation contributes to mechanical allodynia in a rat chemotherapy-induced neuropathic pain model.

Abstract

Chemotherapy-induced neuropathic pain (CNP) is the major dose-limiting factor in cancer chemotherapy. However, the neural mechanisms underlying CNP remain enigmatic. Accumulating evidence implicates the involvement of spinal glia in some neuropathic pain models. In this study, using a vincristine-evoked CNP rat model with obvious mechanical allodynia, we found that spinal astrocyte rather than microglia was dramatically activated. The mechanical allodynia was dose-dependently attenuated by intrathecal administratration of L-α-aminoadipate (astrocytic specific inhibitor); whereas minocycline (microglial specific inhibitor) had no such effect, indicating that spinal astrocytic activation contributes to allodynia in CNP rat. Furthermore, oxidative stress mediated the development of spinal astrocytic activation, and activated astrocytes dramatically increased interleukin-1β expression which induced N-methyl-D-aspartic acid receptor (NMDAR) phosphorylation in spinal neurons to strengthen pain transmission. Taken together, our findings suggest that spinal activated astrocytes may be a crucial component of the pathophysiology of CNP and "Astrocyte-Cytokine-NMDAR-neuron" pathway may be one detailed neural mechanisms underlying CNP. Thus, inhibiting spinal astrocytic activation may represent a novel therapeutic strategy for treating CNP.

• Authors: Xi-Tuan Ji, Nian-Song Qian, Tao Zhang, Jin-Mao Li, Xin-Kui Li, Peng Wang, Dong-Sheng Zhao, Gang Huang, Lei Zhang, Zhou Fei, Dong Jia, Le Niu
• Journal: PloS one (PLoS One) Vol. 8 Issue 4 Pg. e60733 ( 2013) ISSN: 1932-6203 [Electronic] United States
• PMID: 23585846 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Interleukin-1beta
• Receptors, N-Methyl-D-Aspartate
• 2-Aminoadipic Acid
• Vincristine
• Minocycline

Topics

• 2-Aminoadipic Acid (pharmacology)
• Animals
• Astrocytes (drug effects, metabolism, pathology)
• Gene Expression
• Hyperalgesia (physiopathology, prevention & control)
• Injections, Spinal
• Interleukin-1beta (genetics, metabolism)
• Male
• Microglia (drug effects, metabolism, pathology)
• Minocycline (pharmacology)
• Neuralgia (chemically induced, metabolism, physiopathology, prevention & control)
• Pain Measurement
• Phosphorylation
• Rats
• Rats, Sprague-Dawley
• Receptors, N-Methyl-D-Aspartate (genetics, metabolism)
• Signal Transduction
• Spinal Cord (drug effects, metabolism, physiopathology)
• Vincristine