Memory-Enhancing and Antioxidant Activities of the Hydroethanolic Leave Extract of Piliostigma reticulatum (Fabaceae) in the Monosodium Glutamate-Induced Alzheimer's Disease Model

Background: Piliostigma reticulatum (Fabaceae) is a plant used in Cameroon for the treatment of madness and migraine. Aims and Objectives: This study aims to evaluate the memory-enhancing and antioxidant activities of the hydroethanolic leaves extract of PR in the monosodium glutamate-induced Alzheimer's disease model. Materials and Methods: The Y-maze, Radial-arm maze and Novel object recognition tests were used to assess short, and long-term memory. At the end of the experiments, the brains of mice were scavenged for biochemical and histological analysis. Results: It was observed that the hydroalcoholic extract of PR leaf significantly reversed the percentage of spontaneous alternation compared to the negative control group at the different doses tested (p<0.01; p<0.001) in the Y-maze test. In the radial arm maze test, the extract significantly (p<0.001) reduced the time spent consuming the bait, the number of reference memory and working memory errors at all doses. The treatment of animals with hydroethanolic extract of PR resulted in a significant increase in the discrimination index (p<0.001) in the unfamiliar object recognition test. In addition, the extract significantly (p < 0.01); p < 0.001) decreased acetylcholinesterase activity,and MDA levels at all tested doses; and significantly (p < 0.05; p < 0.001) increased SOD level and Catalase activity in comparison to the negative control group. The histological analysis showed that the extract of Piliostigma reticulatum protected the different structures of the hippocampus against damage caused by monosodium glutamate. Conclusion : The memoryenhancing induced by the hydroethanolic leaves extract of Piliostigma reticulatum could be due to his antioxidant and anticholinesterase properties. These effects could justify the use of this plant to manage nervous system affections.