<i>Echinophora platyloba</i> Essential Oil: Chemical composition and Antidepressant-Like Effects in Reserpinized Mice

Background: Oxidative stress has been implicated as a contributing factor in the pathophysiology of depression and anxiety, potentially mitigated through the application of antioxidant-rich medicinal herbs. Among these, Echinophora platyloba DC., an endemic plant, was identified as a promising candidate for investigation. This study aimed to characterize the phytochemical profile of the essential oil of E. platyloba and evaluate its efficacy in alleviating depressive-like behaviors and oxidative stress in mice. Methods: The essential oil extracted from the aerial parts of E. platyloba was subjected to gas chromatography-mass spectrometry (GC/MS) analysis to identify its chemical composition. A total of 60 adult male NMRI mice were randomly assigned to six groups: a negative control group, a reserpine-treated group, a positive control group, and three treatment groups receiving reserpine combined with E. platyloba essential oil at doses of 50, 75, or 100 mg/kg. Behavioral assessments, including the tail suspension test (TST) and forced swim test (FST), were conducted to evaluate depressive-like behaviors. Additionally, biochemical assays were performed to quantify antioxidant capacity and oxidative stress markers. Results: Administration of the essential oil significantly reduced locomotor activity in the open field test and substantially decreased immobility times in both the FST and TST, suggesting robust antidepressant-like effects. At a dose of 50 mg/kg, the essential oil significantly enhanced antioxidant capacity in brain and serum samples while reducing malondialdehyde (MDA) levels, a key indicator of oxidative stress, in these tissues. The GC/MS analysis revealed that myristicin, α-phellandrene, and neocnidilide were the predominant constituents of the essential oil. Conclusion: The essential oil of E. platyloba demonstrated significant antidepressant-like activity and effectively attenuated oxidative stress associated with depressive states, underscoring its potential as a therapeutic agent for depression management.