Exercise keeps body young and healthy

Exercise is a vital element of a healthful lifestyle; it helps
maintain heart health, improve mood, and fight weight gain. New research
also suggests that it can protect a person’s cognitive skills, and a
new study uncovers fresh information as to how this can happen.

According to a study covered on Medical News Today last year,
engaging in regular, leisurely exercise can help keep the body young and
healthy.

The same appears to be true for the relationship between exercise and
the mind; only 10 minutes of physical activity may boost cognitive
function in the short-term.

Meanwhile, exercising regularly for 6 months could actually reverse the symptoms of mild cognitive impairment.

Starting from such evidence, which suggests that exercise has a
protective and even healing effect on brain functioning, a team of
researchers from numerous international academic institutions has
recently investigated some of the biological mechanisms that underlie
this relationship.

The researchers came from institutions including the Federal
University of Rio de Janeiro in Brazil and the Taub Institute for
Research on Alzheimer’s Disease and the Aging Brain at Columbia
University in New York City, NY.

They conducted the new research — the findings of which appear in the
journal Nature Medicine — in a mouse model, and it suggests that a
protein and hormone released during exercise might be the main factor
behind slowing cognitive impairment linked to conditions such as
Alzheimer’s disease.

The memory-boosting protein

In the new study paper — the first author of which is Mychael
Lourenco, from the Federal University of Rio de Janeiro — the scientists
explain that in Alzheimer’s disease, as well as in other
neurodegenerative conditions, hormonal signals are impaired.

“Failure of hormone-initiated signaling pathways,” the authors
explain, “has been associated with brain disorders, including
[Alzheimer’s disease].”

This has led investigators to target such signaling pathways in an
effort to find better treatments and preventive approaches for cognitive
impairment.

Lourenco and team started by looking at hormonal levels in the
hippocampus and cerebral spinal fluid of people with Alzheimer’s. Then,
they repeated the investigation in a mouse model of the condition.

They found that in Alzheimer’s, the levels of a protein and hormone
called irisin, as well as those of its precursor — fibronectin type III
domain-containing protein 5 (FNDC5) — are significantly reduced in both
the hippocampus and the cerebrospinal fluid.

The researchers explain that irisin is a myokine, a messenger protein
released by muscle cells in response to the contractions that occur
during physical activity.

Potential for ‘an attractive novel therapy’

Mice that the researchers engineered to express lower-than-normal
levels of irisin in the brain had trouble with short-term memory and
less of an ability to strengthen synapses. These are the links between
neurons that support information flow and memory recall in the brain.

However, when the researchers increased irisin level in rodents, they
found that this boosted their memory as well as their ability to form
and strengthen new synapses.

They also made another interesting find: when they blocked irisin
signaling in mice, the animals no longer enjoyed the cognitive boost
normally offered by exercise. This further strengthens the idea that
this protein is key to safeguarding memory and brain health.

The study’s results thus suggest that this exercise-induced protein
could become an important new therapeutic target for neurodegenerative
conditions. In the paper, the authors write:

“Our findings suggest that FNDC5/irisin could comprise an attractive
novel therapy aimed to prevent dementia in patients at risk, as well as
delay its progression in patients at the later stages, including those
who can no longer exercise.”

Still, the team cautions that the mechanisms through which irisin
influences brain function remain poorly understood, and that further
studies are needed to get a more complete picture of these processes.

*This article by Maria Cohut was originally published byMedical News Today.