According to a new study from researchers at The Ohio State
University, long-term stress destroys memory, and the immune system plays a vital
role in the cognitive decline.
Long-term stress has been known to cause chronic muscle tension,
heart problems, and fertility problems in both men and women. Now, the latest
study performed in mice and published in the Journal of Neuroscience
suggests chronic stress causes inflammation in the brain, which ultimately leads
to memory loss.
The researchers said that the study in mice could one day bring
about treatment for repeated, long-term mental attack such as the ones sustained
by soldiers, bullying victims, and those who have to deal with beastly bosses.
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Lead researcher Jonathan Godbout, Associate Professor of
neuroscience at Ohio State said:
"This is chronic stress. It's not just the stress of giving a
talk or meeting someone new.”
The first of its kind study was aimed to build the link between short-term memory and prolonged stress. Researchers
stressed out several mice by periodically putting a much more aggressive mouse
into their cage. [Read more Eating
sweet food forms memory of the meal – findings could encourage novel treatment for
obesity]
"The stressed mice didn't recall it. The mice that weren't stressed, they really remembered it," said Godbout.
The stressed-out rodents had changes in their brains, including inflammation brought on by their own immune system. Short-term memory loss was caused by inflammation in the brain, itself the result of the appearance of immune cells called macrophages.
Thus, the researchers pinned the brief memory loss on inflammation, and on the immune system. [Read more How many carbs should you eat if you’re trying to lose weight?]
Godbout said that the effect on memory and evidence that the inflammation in the brain is caused by the immune system are crucial new discoveries.
"It's possible we could identify targets that we can treat pharmacologically or behaviorally," he said.
John Sheridan, co-author and Associate Director of Ohio State's Institute for Behavioral Medicine Research believes it could be that there are ways to interrupt the inflammation.
The mice in the study were exposed to what psychologists call 'repeated social defeat' – in other words they were bullied by a dominant alpha mouse. This was aimed to mimic humans who experience chronic psychosocial stress. [প্রতিদিন কফি পান আপনাকে দীর্ঘদিন বেঁচে থাকতে সাহায্য করবে]
Researchers want to bring to light the secrets behind stress and mood and cognitive problems with a long-term goal of discovering ways to help people who are depressed, anxious and suffer from conditions such as post-traumatic stress disorder (PTSD).
They found that the bullied mice had problem with spatial memory and avoided social contact for up to four weeks, indicating depressive-type behavior.
The stress, it seemed, was causing the mice’s immune systems to attack their own brains, causing inflammation. [প্রতিদিন ফ্রেঞ্চ ফ্রাই খাওয়ার অভ্যাস আপনার মৃত্যু ত্বরান্বিত করতে পারে]
The researchers dosed the mice a drug known to reduce inflammation to see how they would respond. They found that neither the problem in their brain-cell nor the symptoms of depression went away. However, there were no more memory loss and inflammatory macrophages.
The finding led to the conclusion that post-stress memory problem is directly connected to inflammation, and the immune system, rather than brain damage. The impact on memory and confirmation that brain inflammation is caused by the immune system are important new discoveries, said Professor Godbout, and could open new avenues for immune-based treatments. [Read more Changes in brain occur 20 years before Alzheimer’s onset]
Sheridan concluded:
“Stress releases immune cells from the bone marrow and those cells can traffic to brain areas associated with neuronal activation in response to stress.”
“They're being called to the brain, to the center of memory.”
While this isn’t the first time researchers tried to find
the link between chronic stress and memory loss, or between inflammation and
depression, it gives a new, encouraging connection between all four. The
doctors could be benefited by it which may enable them to prescribe more
treatments for conditions that are focused on the immune system such as,
depression, and anxiety.