Fish Oil and Primrose Oil Suppress the Progression of Alzheimer's Like Disease Induced by Aluminum in Rats

The role of fish oil, primrose oil and their mixture in ameliorating the changes in Alzheimer's like model was evaluated in rats. Primrose oil and primrose/fish oil mixture fatty acids composition was assessed by gas chromatography. The rat experiment consisted of 5 groups; the first fed on balanced diet as control normal (CN); the other four groups treated with intraperitoneal aluminum lactate and consumed dyslipidemic diet; one group served as control Alzheimer's like disease (CA) while the other three groups (test groups) received daily oral dose from primrose oil, fish oil and primrose/fish oil mixture separately for 5 weeks. Results showed primrose oil and primrose/ fish oil mixture to contain gamma linolenic acid as 9.15 and 4.3% of total fatty acids, respectively. Eicosapentaenoic and docosahexaenoic were present as 10.9 and 6.5 %, respectively in the oil mixture. Dyslipidemia and increased erythrocyte sedimentation rate (ESR), plasma butyrylcholinesterase (BChE), brain malondialdehyde (MDA) and NO with decrease in plasma magnesium, brain catalase, reduced glutathione, body weight gain and brain weight were demonstrated in CA compared to CN. Brain histopathology and immuno-histochemistry showed neuronal degeneration and neurofibrillary tangles with elevated myeloperoxidase and nuclear factor-kappa B in CA compared to CN. The tested oils demonstrated neuro-protection reflected in the variable significant improvement of biochemical parameters, immuno-histochemistry and brain histopathology. Primrose/fish oil mixture was superior in reducing ESR, brain MDA, plasma activity of BChE and brain histopathological changes along with elevating plasma magnesium. Primrose/fish oil mixture and fish oil were more promising in improving plasma high density lipoprotein cholesterol (HDL-C) than primrose. Fish oil was the most efficient in improving plasma total cholesterol (T-C), low density lipoprotein cholesterol and T-C /HDL-C. Primrose/fish oil mixture and primrose oil were superior in elevating brain catalase compared to fish oil. Other parameters were equally improved by the different oil treatments. Primrose oil, fish oil and their mixture reduced the progression of Alzheimer's disease in rats with superiority to primrose/fish oil mixture.

Keywords: Alzheimer’s disease; aluminum; fish oil; primrose oil; rats.