Anticholinesterase and Antioxidative Properties of Aqueous Extract of Cola acuminata Seed In Vitro

Background. Cola acuminata seed, a commonly used stimulant in Nigeria, has been reportedly used for the management of neurodegenerative diseases in folklore without scientific basis. This study sought to investigate the anticholinesterase and antioxidant properties of aqueous extracts from C. acuminata seed in vitro. Methodology. The aqueous extract of C. acuminata seed was prepared (w/v) and its effect on acetylcholinesterase (AChE) and butyrylcholinesterase activities, as well as some prooxidant (FeSO4, sodium nitroprusside (SNP), and quinolinic acid (QA)) induced lipid peroxidation in rat brain in vitro, was investigated. Results. The results revealed that C. acuminata seed extract inhibited AChE (IC50 = 14.6 μg/mL) and BChE (IC50 = 96.2 μg/mL) activities in a dose-dependent manner. Furthermore, incubation of rat's brain homogenates with some prooxidants caused a significant increase P < 0.05 in the brain malondialdehyde (MDA) content and inhibited MDA production dose-dependently and also exhibited further antioxidant properties as typified by their high radicals scavenging and Fe(2+) chelating abilities. Conclusion. Inhibition of AChE and BChE activities has been the primary treatment method for mild Alzheimer's disease (AD). Therefore, one possible mechanism through which the seed exerts its neuroprotective properties is by inhibiting cholinesterase activities as well as preventing oxidative-stress-induced neurodegeneration. However, this is a preliminary study with possible physiological implications.