"Stress Kills" is a familiar refrain from healthcare providers, fitness professionals, counselors and anyone else in the field of neuroscience and health. Stress is a condition that impacts daily life as well as every system in the body. It can cause a myriad of health problems, but it begins in the brain.
Researchers at the Society for Neuroscience 2017 meeting held a press conference to highlight research into how the brain reacts to stress. Some of the highlights included finding the mechanisms behind the stressors and their impact on the mind. Experts know that adverse effects from stress exist, but some of the underlying factors on how exactly it happens are not well understood.
One of the topics was about finding biological evidence of stress-related trauma. Too often in mental illness, the advice is that "It's all in your head, just put it out of your mind." Finding proof of damage from stress is the best way to learn how to treat it. Researchers from the University of New Mexico Health Sciences Center talked about their work with children who had experienced trauma and were in cognitive behavioral therapy. The team there wanted to see if the stress was causing changes to the DNA of the children. DNA methylation is a biochemical process that can be manipulated to turn genes on or off.
The researchers explored the missing link between DNA methylation, a reversible biochemical process that turns genes "on" or "off." When they looked at elevated cortisol levels in the children (a common factor in those who have experienced trauma) and compared them to methylation patterns in saliva, there was a relationship between high levels of the stress hormone and epigenetic changes. In total there were 174 genes that were altered in children who had changes in methylation along with high cortisol, and these changes impacted the whole body, not just the brain.
A group of scientists from Columbia University was also highlighted for their work in neurogenesis as an antidote to stress. The hippocampus in the brain could be called "stress central." This region is responsible for learning, processing memories, recognizing fear and safety and is very reactive to stress. In a mouse model, the investigators looked at genetically altered mice that produced more than the usual amount of new cells in the hippocampus. These neurogenerative super mice were more resilient when experiencing stress than typical mice. Using microscopy in real time, the team was able to see that mice who did not have large numbers of new cells in the hippocampus experienced more anxiety during stress, suggesting a treatment avenue that targets hippocampal neurogenesis for patients with depression or PTSD.
Another study that was featured was from researchers at Northwestern University who looked at a bacterium called Mycobacterium vaccae, which is harmless and found in soil. When mice who had been exposed to a "double hit" of sleep deprivation and stressful events in their environment, mice who had been injected with this bacterium were able to learn a new task. Mice that did not receive bacterial injections were unable to learn it at all, having been intellectually flummoxed by the stress they experienced.
Other studies that looked at stress and the brain included the role of astrocytes in fear and PTSD from a team at the University of North Carolina Chapel Hill as well as research from the University of Pennsylvania on how stress in fathers can impact their offspring. Gene expression in the sperm of men who are stressed showed increased levels of glucocorticoid receptor (GR) which regulates microRNA in sperm and can impact children who are born when the sperm fertilizes an egg and results in a live birth.
All of the research featured confirms that the brain is dynamic and always changing. Bruce McEwen, head of the Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology at Rockefeller University moderated the press conference and explained, "The brain used to be regarded as an invariant organ after birth, but we now know it is dynamic in its structure and function and experiences adaptive plasticity but also is vulnerable to insults." Check out the video from the event, below.
Source: Society for Neuroscience