Alzheimer's linked to unsaturated acids in the brain: Study

Researchers have found that several unsaturated fatty acids in the brain may be associated with the progression of Alzheimer's disease.

Alzheimer's disease is a neurodegenerative disorder, which causes impaired memory, executive function and language. It accounts for 60-80 per cent of total dementia cases worldwide, with over 46 million people suffering from the disease worldwide. The number of patients is estimated to rise to 131.5 million by 2050.

Currently it is thought that the main reason for developing memory problems in dementia is the presence of two big molecules in the brain called tau and amyloid proteins -- that are shown to start accumulating in the brain up to 20 years prior to the onset of the disease. 

However, the findings, published in the journal PlOS Medicine, showed that the metabolism of omega-3 and omega-6 unsaturated fatty acids were significantly decreased in Alzheimer's brains when compared to brains from healthy patients.

"Our results show a potentially crucial and unexpected role for fats in the onset of dementia. Most surprisingly, we found that a supposedly beneficial omega-3, DHA, actually increased with the progression of the disease," said Cristina legido Quigley from King's College london. 

In the study, the team looked at brain tissue samples from 43 people ranging in age from 57 to 95 years old. 

The researchers then measured the metabolite levels of the brain regions that are commonly associated with neurodegerative diseases -- the middle frontal gyrus and the inferior temporal gyrus -- as well as the metabolite levels in a brain area that is not normally affected by the disease's pathology -- the cerebellum.

The results showed that unsaturated fatty acid metabolism is significantly dysregulated in the brains of patients with varying degrees of Alzheimer pathology.

The main molecules that were different were six small fats -- docosahexaenoic acid, linoleic acid, arachidonic acid, linolenic acid, eicosapentaenoic acid, and oleic acid -- including omegas, which changed in abundance in different regions of the brain.