The Small Molecule Compound Eupalinolide B Ameliorates Depressive Behaviors and Neuropathic Pain in Mice With Spared Nerve Injury: Integrating Network Pharmacology, Molecular Docking, Bioinformatics, Molecular Dynamics Simulation and Experimental Verification

BACKGROUND: Neuropathic pain (NP) frequently co-occurs with depression (DP), exhibiting complex pathogenesis and limited clinical treatment options. This study aims to investigate the efficacy of Eupalinolide B (EB) in alleviating NP co-occurring with DP and its potential molecular mechanisms. METHODS: Combining network pharmacology, molecular docking, and molecular dynamics simulations to screen potential targets for EB, validated through transcriptomic data. Using a sciatic nerve branch-preserving injury (SNI) mouse model, we assessed pain and depression-like behaviors through von Frey testing, hot plate testing, tail suspension testing, forced swimming testing, and open field testing. Concurrently, Western blotting, immunofluorescence, and Nissl staining were employed to analyze relevant molecules and neuropathological alterations. RESULTS: Network pharmacology and bioinformatics analysis identified EGFR, PTGS2, and JUN as the key targets for EB in treating NP combined with DP. Behavioral studies showed that 20 mg/kg of EB significantly alleviated pain in SNI mice and improved depressive-like behaviors. Mechanism research indicated that EB downregulated the expression of EGFR and PTGS2, inhibited the activation of microglia and astrocytes, and reduced neuronal damage. Additionally, EB could upregulate the expression of synaptic proteins (PSD95, SYN1, and BDNF) in the hippocampus. CONCLUSION: EB alleviates neuroinflammation by reducing EGFR and PTGS2 protein expression, modulates synaptic plasticity, and improves pain-depression comorbidity. EB may represent a promising therapeutic approach for pain-related depression.