New research claims Alzheimer’s disease can start in the liver

By Mark Waghorn via SWNS

Alzheimer's disease can start in the liver, according to new research.

Scientists say a rogue brain protein originates in the blood-filtering organ, medications that destroy it may prevent the memory-robbing disease.

It adds to evidence that gorging on fast food increases dementia risk as it fuels production of the protein - known as beta-amyloid.

"The abundance of these toxic protein deposits in the blood could potentially be addressed through a person's diet," said Professor John Mamo, of Curtin University in Australia. "Some drugs could specifically target lipoprotein amyloid - therefore reducing their risk or slowing the progression of Alzheimer’s disease."

The blood-brain barrier (BBB) protects grey matter against foreign bodies meaning most therapies cannot reach the central nervous system.

(Amyloid made in the liver can cause neuro-degeneration so is a far more promising option for treatment

"The protein is thought to be a key contributor to development of Alzheimer's," said Mamo. "It suggests the liver may play an important role in the onset or progression of the disease."

In the brain, amyloid clumps together in plaques. It is one of the main hallmarks of Alzheimer's.

But the protein is also present in other organs - including the liver.

The team genetically engineered mice to produce human amyloid only in liver cells.

It was carried to their brains in blood by lipoproteins rich in fats called triglycerides and they developed neurodegeration and cell loss.

Mamo said the same process happens in humans. Inflammation and dysfunction of cerebral capillaries were also identified in the lab rodents.

"Affected mice performed poorly on a learning test that depends on function of the hippocampus," he said. "The brain structure is essential for the formation of new memories. The findings indicate peripherally derived amyloid has the ability to cause neurodegeneration. It suggests amyloid made in the liver is a potential contributor to human disease."

The findings in PLOS Biology shed fresh light on Alzheimer's and might have major implications for developing better therapies.

"Most models have focused on brain over-production of amyloid," Mamo said. "They mimic the rare genetic cases of Alzheimer's. But for the vast majority it is not thought to be central to the cause. Instead, lifestyle factors may play a more important role. They include a high-fat diet - which might accelerate liver production of amyloid."

It backs previous research linking consumption of trans fats, found in fried food, cakes and biscuits, to dementia.

A study of people over 60 in Japan found those who ate the most trans fats were 52 percent more prone.

An estimated 920,000 people in the UK are living with Alzheimer's and other forms of dementia.

With no cure in sight, there is an increasing focus on lifestyle changes that could reduce the risk.

They include eating plenty of fruit, vegetables, nuts and fish and getting 150 minutes of moderate exercise a week - such as brisk walks.