Evaluation of the Therapeutic Efficacy of Entrapment Neuropathy Unties (ENU) Pharmacopuncture in Neuropathic Pain Caused by Sciatic Nerve Ligation in Mice

Abstract

Background: Neuropathic pain caused by peripheral nerve injury results from abnormal signaling or processing in the nervous system. Pharmacopuncture with Entrapment Neuropathy Unties (ENUs), a multi-herbal formulation, may offer a complementary therapeutic strategy. However, its efficacy has not been scientifically validated in vivo. Methods: A mouse model of sciatic nerve ligation (SNL)-induced neuropathic pain was used. Behavioral assessments were performed using Von Frey filaments to measure mechanical allodynia. Immunofluorescence staining was conducted to detect C-FOS and GFAP expression in the spinal dorsal horn. Quantitative PCR (qPCR) was used to evaluate the expression of inflammatory markers, including Gfap, Iba1, Tnf-alpha, and Il-1 beta. Results: Local administration of ENUs at the injury site significantly alleviated mechanical allodynia induced by SNL (*p < 0.05, **p < 0.01, ***p < 0.001). Treatment with ENUs also led to statistically significant reductions in the expression of C-FOS, GFAP, and pro-inflammatory cytokines (*p < 0.05, **p < 0.01, ***p < 0.001). Among the treatment groups, the ENU V2-middle and V2-high dose groups demonstrated the most pronounced therapeutic effects compared to the saline-treated control group. Conclusion: This study provides the first in vivo evidence supporting the analgesic and anti-inflammatory effects of ENUs in neuropathic pain. ENUs may exert these effects by suppressing glial activation and neuronal sensitization. Further research is warranted to explore its clinical applications and underlying molecular mechanisms.