Extra-Virgin
Olive Oil-Rich Diet Protects Mice from Multiple Forms of Dementia
By Science News Staff / Source
“Extra-virgin olive oil
has been a part of the human diet for a very long time and has many benefits
for health, for reasons that we do not yet fully understand,” said Professor Domenico
Praticò, director of the Alzheimer’s Center at the Lewis Katz School
of Medicine at Temple University.
“The realization that
extra-virgin olive oil can protect the brain against different forms of
dementia gives us an opportunity to learn more about the mechanisms through
which it acts to support brain health.”
In a previous work using a mouse model in which animals were
destined to develop Alzheimer’s disease, Professor Praticò and colleagues
showed that extra-virgin olive oil supplied in the diet protected young mice
from memory and learning impairment as they aged.
Most notably, when the
researchers looked at brain tissue from mice fed extra-virgin olive oil, they
did not see features typical of cognitive decline, particularly amyloid plaques
— sticky proteins that gum up communication pathways between neurons in the
brain. Rather, the animals’ brains looked normal.
The new study shows that
the same is true in the case of mice engineered to develop tauopathy.
In these mice, normal
tau protein turns defective and accumulates in the brain, forming harmful tau
deposits, also called tangles. Tau deposits, similar to amyloid plaques in
Alzheimer’s disease, block neuron communication and thereby impair thinking and
memory, resulting in frontotemporal dementia.
Tau mice were put on a diet supplemented with extra-virgin olive oil at a young age, comparable to about age 30 or 40 in humans.
Six months later, when
mice were the equivalent of age 60 in humans, tauopathy-prone animals
experienced a 60% reduction in damaging tau deposits, compared to littermates
that were not fed extra-virgin olive oil.
Animals on extra-virgin
olive oil-rich diet also performed better on memory and learning tests than
animals deprived of the olive oil.
When the scientists
examined brain tissue from extra-virgin olive oil-fed mice, they found that
improved brain function was likely facilitated by healthier synapse function,
which in turn was associated with greater-than-normal levels of a protein known
as complexin-1. Complexin-1 is known to play a critical role in maintaining
healthy synapses.
The team now plans to
explore what happens when extra-virgin olive oil is fed to older animals that
have begun to develop tau deposits and signs of cognitive decline, which more
closely reflects the clinical scenario in humans.
“We are particularly
interested in knowing whether extra-virgin olive oil can reverse tau damage and
ultimately treat tauopathy in older mice,” Professor Praticò said.
The findings were published in the journal Aging Cell.
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Elisabetta Lauretti et
al. Extra virgin olive oil improves synaptic activity, short‐term
plasticity, memory, and neuropathology in a tauopathy model. Aging
Cell, published online November 24, 2019; doi: 10.1111/acel.13076
