Neuroprotective Effect of Butanol Fraction of Zapoteca portoricensis (Jacq.) H. M. Hern Root on Scopolamine Induced Memory Impairment in Rats
Felix Keneolisa Asogwa *
Department of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, Enugu State University of Science and Technology, Agbani, Enugu State, Nigeria.
Daniel Lotanna Ajaghaku
Department of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, Enugu State University of Science and Technology, Agbani, Enugu State, Nigeria.
Augustine Oluchukwu Asogwa
Department of Obstetrics and Gynaecology, University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu State, Nigeria.
Celestine Obiora Ugwu
Department of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, Enugu State University of Science and Technology, Agbani, Enugu State, Nigeria.
Judith Chinyere Ugwu
Department of Industrial Chemistry, Faculty of Natural Science, Enugu State University of Science and Technology, Agbani, Enugu State, Nigeria.
*Author to whom correspondence should be addressed.
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.
Keywords: Alzheimer’s disease, Zapoteca portoricensis, butanol fraction, scopolamine, memory impairment, Y-maze, acetylcholine, dopamine, serotonin, oxidative stress, reduced glutathione, malondialdehyde