Bogijetong Decoction and its Selected Formulation Relieve the Regulation of Neuropathic Pain by Modulating Anti-Inflammatory Cytokines

Purpose: This study was conducted to identify the anti-inflammatory activities of Bogijetong decoction (BJD) and BJD-derived Be decoction (BeD) in an animal model of neuropathic injury in which the sciatic nerve was ligated.Methods: BJD, BeD, or an isotonic sodium chloride solution vehicle were administrated orally to Sprague-Dawley rats after sciatic nerve ligation under anesthesia. Other Sprague–Dawley rats underwent sham surgery with no drug treatment administered, serving as the sham control group. The anti-inflammatory activities of BJD and BeD were investigated using immunofluorescence staining and Western blot analysis.Results: Iba1 expression markedly decreased following BeD treatment in the sciatic nerve and dorsal root ganglion but not in the spinal cord of the sciatic nerve-ligated animals. BeD treatment reduced tumor necrosis factor-alpha and interleukin-6 levels in the sciatic nerve, dorsal root ganglion, and spinal cord. BJD treatment also reduced Iba1, tumor necrosis factor-alpha, and interleukin-6 levels in the same tissues, although it was less effective than BeD.Conclusion: BeD may exhibit anti-inflammatory activity in peripheral nerves and the spinal cord and may contribute to alleviating neuropathic pain.