Cognitive improvement and hippocampal BDNF/GFAP alterations by Schinus molle essential oil in a rat model of scopolamine-induced amnesia

Ethnopharmacological relevanceSchinus molle L. (Anacardiaceae) has been traditionally used for conditions related to the nervous system and emotional well-being, often through aromatic preparations. However, its cognition-specific effects have not yet been investigated.Aim of the studyTo assess the cognitive effects of the fruit-derived essential oil of Schinus molle L. (SMEO), administered via oral and inhalation routes, in a rat model of scopolamine-induced amnesia.Materials and methodsSMEO was obtained by hydrodistillation and characterised by GC–MS/GC–FID. Amnesic rats received SMEO for 14 days by inhalation (1% or 3%) or oral gavage (100 or 200 mg/kg). Cognition was assessed by Morris water maze (MWM), passive avoidance (PA), and novel object recognition (NOR) tests; locomotion was measured by activity-meter. Hippocampal BDNF and GFAP immunoreactivity were assessed by immunohistochemistry.ResultsSMEO was dominated by α-phellandrene (48.7%). Scopolamine impaired cognition, whereas SMEO attenuated deficits with efficacy comparable to piracetam. Key behavioural and immunohistochemical findings (main omnibus statistical effects) were as follows: In the MWM, treatment and time effects on escape latency were significant (both p < 0.001), and probe performance improved (p < 0.001). PA retention was restored (p < 0.001) and the NOR index improved (p < 0.001), without locomotor changes (all p > 0.05). Scopolamine reduced hippocampal BDNF immunoreactivity in CA1 and DG (p < 0.01) and CA3 (p < 0.001), which was restored by SMEO via both routes. GFAP immunoreactivity was reduced in CA1/CA3/DG (all p < 0.001) and was rescued selectively after inhalation.ConclusionsThese findings provide preclinical evidence consistent with an ethnopharmacological rationale for SMEO and support further translational work to clarify its relevance beyond this experimental paradigm.