Researchers at Trinity College Dublin claim to have made a breakthrough on the cause of Alzheimer’s disease that could hold “tremendous potential” for new therapies, the Irish Times reports.

Alzheimer’s, which is the fourth leading cause of death in people over 65, is characterized in part by the build up of a small protein in the brains of patients. The scientists say that failure to clear the protein “appears to be a major factor” in the build-up of plaques and in the disease process itself.

While the method in which the protein is cleared “remains unclear,” it is “evident” that it needs to be filtered from the brain via the bloodstream.

“Unlike blood vessels anywhere else in the body, those in the brain have properties that strictly regulate what gets in and out of the delicate tissue – this is what is known as the blood-brain barrier,” according to the research.

Researchers believe “periodic clearance” of the protein across the blood brain barrier could lead to new treatments.

“The next steps are to consider how this might be achieved,” they said.

The research, which was published in the international journal Science Advances, was supported by Science Foundation Ireland and the US-based charity, Brightfocus Foundation.

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