Neuroprotective euglobals from Eucalyptus tereticornis Smith. leaves: quantification, network pharmacology-guided in silico analysis, and experimental validation

OBJECTIVES: This study aims to investigate the neuroprotective potential of terpene-linked phloroglucinol derivatives from Eucalyptus tereticornis leaves. METHODS: Euglobals, terpene-linked phloroglucinol derivatives, were isolated using reverse-phase high-performance liquid chromatography (HPLC) and purified by recycle HPLC. Quantification was performed using quantitative 1H NMR. Neuroprotective targets were identified through the GeneCards database, followed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. Network pharmacology integrated molecular docking were employed to identify key bioactive constituents and their targets. The neuroprotective activity of isolated euglobals and the enriched fraction was evaluated in vitro using the N2a neuronal cell line. KEY FINDINGS: High-Resolution Mass Spectrometry (HRMS) and 1H NMR confirmed the presence of euglobals in the enriched fraction of E. tereticornis leaves, with qNMR identifying euglobal-Ia2, euglobal BI-1, and robustadial A and B as major constituents. Network pharmacology and docking revealed the multitarget interactions involving PI3K-Akt, MAPK, mTOR, and NF-κB signalling pathway. In lipopolysaccharide-stimulated N2a cells, tested compounds restored neurite outgrowth, reduced intracellular and mitochondrial reactive oxygen species, suppressed IL-1β, enhanced IL-10, and modulated NF-κb/Nrf2-HO-1-SOD signalling. CONCLUSION: Network pharmacology identified euglobals as potential neuroprotective compounds. Tested compounds exhibited significant neuroprotective effects in the N2a cell line. The integrated approach combining qNMR, network pharmacology, and in vitro validation highlights euglobals as promising neuroprotective agents.