Researchers have found obesity can cause learning and memory issues because the condition breaks down our protective blood brain barrier.
Previous research has found that chronic activation of the receptor Adora2a on the endothelial cells that are around the barrier in our body can allow certain factors enter the brain from the blood and impact how the neurons function. "We know that obesity and insulin resistance break down the blood brain barrier in humans and animal models, but exactly how has remained a mystery," author of the study Dr Alexis M Stranahan, a neuroscientist in the MCG Department of Neuroscience and Regenerative Medicine at Augusta University, told a news portal.
However, the new study, conducted by scientists at Medical College of Georgia, has found when obesity blocks Adora2a in a model the barrier function is maintained. Adenosine is a neurotransmitter that helps us to go to sleep, as well as regulate blood pressure. It also activates receptors Adora1a and Adora2a on endothelial cells. This function helps to maintain proper function and a good relationship between blood flow and brain activity. However, obesity can cause chronic activation in the brain.
The risk of cognitive impairment is high for people with obesity and diabetes because these conditions can cause structural changes in the hippocampus, which is involved in memory and learning. Because fat causes inflammation in the brain, reducing it may prevent memory loss.
To investigate this matter, researcher fed mice a diet high in fat. Within 16 weeks the researchers noted an increase in fasting glucose and insulin concentrations in all of them. These are strong indicators of diabetes. The team also found that in the hippocampus, obesity increased the permeability of the blood brain barrier to tiny molecules. When the mice were given a drug to block Adora2a, it also blocked problems with barrier permeability. This means it could help reduce the risk of memory loss caused by obesity.
"If an individual has already progressed to insulin resistance, these studies underscore the importance of controlling blood sugar levels and avoiding progressing to insulin deficiency (diabetes), which opens the blood brain barrier even further," Stranahan told a news portal.
However, further investigation is needed to understand if this could work on humans. The study's finding was originally published in the Journal of Neuroscience.
Previous research has also found that chronic pain can cause memory loss and may lead to dementia. "People with chronic pain tend to perform poorly on cognitive tests, particularly of memory and attention, compared with people who don’t have chronic pain, but we did not know whether that is due to faster cognitive decline or worse cognitive performance overall,” lead study author Dr. Elizabeth Whitlock of the University of California, San Francisco, told a news portal.
In order to minimize the impact and quality of life due to this condition, experts urge people suffering from chronic pain to treat the condition as soon as possible.
