Central Inhibitory and Mechanism of Anxiolytic Potential of Ethanol Leaf Fractions of Milicia Excelsa C. C. Berg (Moraceae) in Mice

Central Inhibitory and Mechanism of Anxiolytic Potential of Ethanol Leaf Fractions of Milicia Excelsa C. C. Berg (Moraceae) in Mice

Lateef Abiola Akinpelu1*, ItunuOluwa Michael Akanmu2, Moses Atanda Akanmu3

 

  1. Department of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of Ilorin, Kwara State.
  2. Department of Pharmacology and Toxicology, College of Pharmacy, Igbinedion University, Okada, Edo State.
  3. Department of Pharmacology, Faculty of Pharmacy, Obafemi Awolowo University Ile-Ife, Osun State.

 

 

 

Key words:

 Aqueous fraction, central inhibitory effect, anxiolytic, GABAA benzodiazepine receptor.

 

 

 

 

*Corresponding author:

akinpelu.la@unilorin.edu.ng,;
DOI:https://doi.org/10.61594/tnpr.v6i4.2025.147

Page No: 334-345
Volume: 6, Issue 4, 2025
Trends in Natural Products Research
Copy Right: NAPREG

Abstract

Milicia excelsa has been demonstrated to possess anxiolytic potential in earlier study. This study aimed to investigate the central inhibitory and anxiolytic effects of its fractions in mice. The n-hexane (HF), ethyl acetate (EF), n-butanol (BF) and aqueous (AF) fractions of the ethanol leaf extract were investigated using novelty-induced behaviours (rearing and locomotion) while the anxiolytic effects were assessed using hole board test (HBT), elevated plus maze (EPM) and staircase models (SCM) at 250, 500 and 1000 mg/kg in mice. The neural mechanism of anxiolytic effect of the most active fraction was also investigated using flumazenil (3 mg/kg, i.p.) and cyproheptadine (0.5 mg/kg, i.p.). The EF and AF significantly (P < 0.05) reduced rearing and locomotion compared to control suggestive of central inhibitory actions. Similarly, EF and AF significantly (P < 0.05) reduced head dip in HBT compared to control indicative of sedative effects. All the fractions significantly (P < 0.05) reduced open arm avoidance indices (OAAI) compared to control consistent with anxiolytic potentials. The AF significantly (P < 0.05) reduced the number of rearing in SCM compared to control suggestive of anxiolytic property. Flumazenil significantly (P < 0.05) reversed the anxiolytic effect of AF implicative of the involvement of GABAergic pathways in its anxiolytic actions. However, cyproheptadine did not show any significant (P < 0.05) reversal of the anxiolytic effect of AF suggesting noninvolvement of serotonin in the anxiolytic effect of AF. This study therefore, concluded that the fractions of Milicia excelsa leaf extract may possess central inhibitory and anxiolytic effects and its mechanism may involve GABAA benzodiazepine pathway.