Neuroprotective Effect of Butanol Fraction of Zapoteca portoricensis (Jacq.) H. M. Hern Root on Scopolamine Induced Memory Impairment in Rats

Abstract

Background: Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterised by cognitive decline, memory impairment, and oxidative stress. Aim: This study investigated the neuroprotective effects of the butanol fraction of Zapoteca portoricensis root (BFZP) in a scopolamine-induced rat model of AD-related cognitive deficits. Methods: Sprague-Dawley rats were pretreated with BFZP at doses of 100, 200, and 400 mg/kg, p.o., or donepezil 5 mg/kg, p.o., for 14 days prior to scopolamine administration (1 mg/kg, i.p.). Cognitive performance was assessed using the Y-maze test. Oxidative stress markers and neurotransmitter levels were quantified in brain homogenates. Results: Behavioural assessments revealed that BFZP significantly improved spatial memory. Latency was reduced to 6.00 ± 1.18 s at 200 mg/kg, and time spent in the novel arm increased to 68.00 ± 43.98 s, compared with scopolamine controls (p < 0.001). Biochemically, BFZP at 400 mg/kg restored acetylcholine (6.64 ± 0.11 nmol/g), dopamine (9.20 ± 0.16 nmol/g), and serotonin (7.65 ± 0.20 nmol/g) levels. At 100 mg/kg, BFZP decreased malondialdehyde (3.01 ± 0.13 nmol/g) and elevated glutathione levels relative to scopolamine, indicating potent antioxidant activity. Conclusion: These findings suggest that BFZP ameliorates cognitive deficits through antioxidant and cholinergic mechanisms. The results support its traditional use and highlight its potential as a novel therapeutic candidate for AD, warranting further investigation into its mechanisms and long-term efficacy.