Background: Essential oils have been used as remedies since ancient times for the treatment of numerous illnesses on account of their wide range of biological activities. Varying pharmacological responses in the nervous system leading to anxiolytic, antidepressant, sedative, and anticonvulsant effects. Aims: This research aims to extract oil from Egyptian Clementine by Screw Press to improve the properties of producing oil and to evaluate the effect of Clementine oil extract on Alzheimer's disease (AD) in rats induced by AlCl3.
The maximum yield of clementine oil was about 11 %, healthy and low fatty acid at screw temperatures 40°C and motors speed 25 rpm. The fatty acid composition was analyzed by GC/MS. In vivo experiment AD-induced rats were orally administered 100mg/kg b.wt of AlCl3 for two months. Clementine oil was administered in a dose of 100 ul /kg b.wt. for 6 weeks compared to reference drug donepezil 10 mg/kg b.wt.. Acetylcholine esterase (AchE), Acetylcholine (Ach), ,noradrenaline (NA), adrenaline (AD),serotonin (5-HT),oxidative stress marker ;malondialdehyde (MDA), superoxide dismutase (SOD),catalase (CAT),total antioxidant capacity (TAC), tau protein and β-amyloid were estimated in brain tissue and serum of AD-induced rats and therapeutic group compared to control. Results: Histological investigation of hippocampal of AD rats revealed severe neuropathologic damage exhibited by shrunken and necrosis of pyramidal neurons associated with the formation of neurofibrillary tangles, the proliferation of glia cells, and neuronophagia. Strong immune reactivity of hypertrophied astrocytes with deeply brown stained GFAP positive processes was noticed in the cerebral cortex and hippocampus of AD rats. The hippocampus of rats treated with reference drug revealed necrosis of some pyramidal neurons and neurofibrillary tangles. However, rats treated with oil showed marked restoration of the histological structure with only sporadic necrosis of pyramidal neurons. The cerebral cortex showed numerous neuropathologic alterations described by psychosis and necrosis of neurons as well as the formation of neurofibrillary tangles and focal gliosis. Further, oil treatment exhibited regression of the histopathological damage. While down-regulation of the immune GFAP immune reaction was seen in the cortex and hippocampus of rats treated with either reference drug or with the oil. Additionally, noticeable improvement was detected in all measured parameters upon treated AD-induced rats with Clementine oil. Conclusion: It could be concluded that remarkable improvement in all detected parameters resulting from treatment of AD rats with Clementine oil extracted by Screw press techniques due to its high antioxidant activity. Essential oils (Eos) has shown anticholinesterase activity, which might be advantageous for the development of drugs for AD treatment since cholinesterase has been recognized as one of its potential targets.