In vivo and in silico studies on the nootropic effect of Strychnos innocua Del. (Loganiaceae) leaf ethanol extract
Chinedu Enegide, Ujunwa Emelda Ezeanochie, Israel Ofejiro Efejene, Emmanuella Chukwufumnanya Nwegbu, Osasengo Precious Osifo, Eugene Ehimare, Esther Adaeze Ossai, Nwabenu Opia Okwaji
- Department of Pharmacology, College of Medical & Health Sciences, Novena University, Ogume, Delta State,
Nigeria. - Department of Pharmacology & Toxicology, Faculty of Pharmacy, Novena University, Ogume, Delta State, Nigeria.
- Department of Pharmacology, Faculty of Basic Medical Sciences, Southern Delta University, Ozoro, Delta State,Nigeria.
| Key words:
Nootropic, Acetylcholinesterase, Strychnos innocua, GC-MS
*Corresponding author: emeldaujunwa706@gmail.com; Page No: 215-224 |
AbstractNootropics, often referred to as cognitive enhancers, are substances that improve cognitive functions, such as memory, learning, attention, and executive processes. Memory is a fundamental cognitive function that allows individuals to encode, store, and retrieve information essential for their daily activities. Disruptions in memory processes can significantly impair learning, decision making, and overall quality of life. While synthetic nootropics have been extensively studied, their side effects and variable efficacy have sparked interest in natural alternatives, particularly plant-derived extracts rich in bioactive compounds. This study aimed to evaluate the nootropic effect of Strychnos innocua leaf ethanol extract using in vivo and in silico models. The bioactive compounds present in the extract were identified using GC-MS analysis. The Y-maze test was used to evaluate the in vivo nootropic activity of the extract in adult male Swiss albino mice. Graded extract doses (200 – 800 mg/kg) were used in this study. In the in silico study, the binding interactions of the bioactive constituents of the extract were evaluated using iGEMDOCK. GC-MS analysis revealed the presence of 40 compounds, including myo-inositol 4-C-methyl, vitamin E, 9,12,15-octadecatrienoic acid (Z, Z, Z), and phytol. The in vivo study showed a non-dose-dependent effect, with significant improvement in novel arm preference at 200 mg/kg, indicating enhanced spatial working memory. Higher doses (400–800 mg/kg) resulted in reduced cognitive performance, which aligns with the inverted-U model of cognitive function. In addition, the in silico study outcome showed a good binding interaction of its bioactive composition, such as myo-inositol, 4-C-methyl, 9,12,15-octadecatrienoic acid (Z, Z, Z), and phytol, to the active site of acetylcholinesterase. The results of this study show that S. innocua leaf ethanol extract enhances cognitive function in mice, likely through the modulation of cholinergic and monoaminergic neurotransmission. |