Modulation of cognitive activity by plant-based extracts (Allium cepa, Coffea robusta, and Brassica oleracea) through the phosphodiesterase 4B inhibition: Insite from a Mice model study

Background: Cognitive dysfunction (CD) is a growing issue worldwide, despite extensive advancements and clinical research in therapeutic strategies. A potential approach in order to treat CD entails phosphodiesterase 4B (PDE4B), which has a big impact on how well memory works. Objective: The current investigation aimed to quantify quercetin, sinigrin, and chlorogenic acid in the extracts Allium cepa (A. cepa), Brassica oleracea (B. oleracea), and Coffea robusta (C. robusta), respectively using thin layer chromatography (TLC)-densitometry assessments and to figure out the memory-enhancing effect of combination extract (A. cepa, B. oleracea, and C. robusta) in mice. Methods: The ethanol extracts of B. oleracea and A. cepa were prepared individually using the maceration method, while the C. robusta aqueous extract was obtained through infusion method. Quantification assessment of quercetin, sinigrin, and chlorogenic acid was carried out using TLC-densitometry. While the Morris water maze (MWM) test was used to determine the memory potential of mice. Subsequently, administering the combination extracts, memory performance was evaluated with the MWM test. Additionally, the hippocampus of the mice was analyzed against cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), cAMP-responsive element-binding protein (CREB), and brain-derived neurotrophic factor (BDNF) activities using Western blot and ELISA methods. Results: The amounts of quercetin, sinigrin, and chlorogenic acid in the extracts estimated by TLC-densitometry. The combination extracts enhanced cognition in scopolamine-induced CD in mice during behavioral test. Furthermore, the combination extracts blocked PDE4B activity and exhibited memory potential by elevating hippocampal biomarkers. Conclusion: In summary, A. cepa, B. oleracea, and C. robusta extracts serve as an excellent sources of quercetin, sinigrin, and chlorogenic acid, respectively. The combination of these extracts was found to improve memory function in mice. © 2025