EFFECT OF THE ETHYL ACETATE FRACTION EXTRACTED FROM THE LEAVES OF EUGENIA INVOLUCRATA (MYRTACEAE) ON THE ACTIVITY OF ACETYL CHOLINESTERASE AND BUTYL CHOLINESTERASE IN DIABETIC RATS

Abstract

During persistent hyperglycemia, oxygen free radical production increases through glucose self-oxidation, causing oxidative stress. Alzheimer's Disease is associated with decreased brain neurotransmitters, such as acetylcholine, norepinephrine, and serotonin. Considering that persistent diabetes causes hyperglycemia leading to increased free radical production, that free radicals may contribute to the neurodegeneration process and that Eugenia involucrata has phenolic and flavonoid compounds acting as antioxidants, the aim of this study was to verify the effects of chronic and acute administration of the ethyl acetate fraction (FAE) obtained from the leaves of the species Eugenia involucrata on the effects caused by diabetes on the activity of acetylcholinesterase (AChE) in brain and butyrylcholinesterase (BuChE) in rat blood. Therefore, 60-day-old Wistar rats were divided into 9 groups: Control group, Rivastigmine group, FAE group (50, 100 and 150 mg / kg), FAE group (50, 100 and 150 mg / kg) + Diabetes and Diabetic group. 12 hours after the last treatment (acute and chronic), the animals were sacrificed by decapitation in the absence of anesthesia. The brain was removed for AChE activity determination and blood collected for BuChE activity determination. In acute and chronic treatment, FAE inhibited AChE activity in the cerebral cortex and hippocampus when compared with the control group. Regarding BuChE activity in chronic treatment, FAE inhibited enzyme activity when compared to the control group. Thus, it is suggested that FAE has anticholinesterase action.

Keywords: Eugenia involuncrata, cholinesterases, dibetes, oxidative stress.