Recent quotes:

Long-term stress in dogs linked to the owner-dog relationship -- ScienceDaily

"The results showed that the owner's personality affected the stress level in hunting dogs, but interestingly enough not in the ancient dogs. In addition, the relationship between the dog and the owner affected the stress level of the dogs. This was the case for both types, but the result was less marked for the ancient dogs," says Lina Roth, senior lecturer in the Department of Physics, Chemistry and Biology at Linköping University. In a previous study, the same researchers had seen that dogs from herding breeds, which have been genetically selected for their ability to collaborate with humans, mirror the long-term stress level of their owner. When the researchers now added information about the relationship of the herding dogs to their owner, it became clear that the relationship was significant for the long-term stress levels also in these dogs.

Refined carbs may trigger insomnia, finds study -- ScienceDaily

They found that the higher the dietary glycemic index -- particularly when fueled by the consumption of added sugars and processed grains -- the greater the risk of developing insomnia. They also discovered that women who consumed more vegetables and whole fruits (not juices) were less likely to develop insomnia. "Whole fruits contain sugar, but the fiber in them slow the rate of absorption to help prevent spikes in blood sugar," says Gangwisch. "This suggests that the dietary culprit triggering the women's insomnia was the highly processed foods that contain larger amounts of refined sugars that aren't found naturally in food." Since most people, not just postmenopausal women, experience a rapid rise in blood sugar after eating refined carbohydrates, the authors suspect that these findings may also hold true in a broader population.

Bone, not adrenaline, drives fight or flight response

The researchers found in mice and humans that almost immediately after the brain recognizes danger, it instructs the skeleton to flood the bloodstream with the bone-derived hormone osteocalcin, which is needed to turn on the fight or flight response. "In bony vertebrates, the acute stress response is not possible without osteocalcin," says the study's senior investigator Gérard Karsenty, MD, Ph.D., chair of the Department of Genetics and Development at Columbia University Vagelos College of Physicians and Surgeons.

In depression the brain region for stress control is larger -- ScienceDaily

So far, it is known that people more predisposed to depression show a dysregulation of the endogenous stress response system, otherwise known as the hypothalamic-pituitary-adrenal axis (HPA axis), which is normally triggered when we are faced with a stressful situation. This response increases the amount of cortisol, providing the body with more energy when faced with a potential threat or challenge. Once the challenging situation has passed, several control mechanisms in the HPA axis normally ensure the system returns to a balanced state. In people who suffer with depressive disorder or who are more predisposed, this is not the case. Instead, a malfunction of the feedback mechanism results in a stress response operating at full throttle, even when there is no apparent stressful situation. Until now, the underlying reason for this hyperactive stress response system and the role of the hypothalamus as its overall control unit has remained unclear.

Stress hormone is key factor in failure of immune system to prevent leukemia -- ScienceDaily

They do this by using cortisol to force the release of a protein, latrophilin 1. This in turn causes the secretion of another protein, galectin-9, which suppresses the body's natural anti-cancer immune mechanism. Dr Sumbayev's team, working with researchers from two German universities and the UK's Diamond Light Source facility, found that although healthy human white blood cells are not affected by cortisol they become capable of releasing latrophilin 1 when malignant transformation takes place. Malignant AML cells then use cortisol to increase the release of latrophilin 1 so that they can use it to avoid the immune system. The study concluded that galectin-9, as well as a natural binding partner of latrophilin 1 -- known as FLRT3 -- which are both present in human blood plasma, are the most promising targets for future anti-AML immune therapy.

Why "Wilder" Nature Is Better for Your Health | Outside Online

In addition, visitors to the park and wilderness area had increased levels of joy; and visitors to the wilderness area were the only ones to have a significant decrease in cortisol levels. That’s consistent with the “levels of nature” hypothesis, much like another recent study that saw greater improvements in insulin sensitivity and oxidative stress in Korean women who spent a half-day in a “wild forest” compared to a “tended forest.”

The immune system and the pathogenesis of depression

There is bidirectional communication between the HPA axis and the immune system. Cytokines activate the HPA axis and thus lead to the release of cortisol, the stress hormone, which ordinarily suppresses the immune response. Cortisol also inhibits its own release and thus the body is able to maintain a stable immune response through a tightly regulated feedback inhibition system. This regulation mechanism seems to be dysfunctional in depressive disorders and is thought to occur because of cytokine mediated receptor resistance to cortisol, thus impairing feedback inhibition. This essentially means that cytokines make cortisol unable to act on the receptors that would inhibit its release. Long story short — the HPA axis is hyperactive because of cytokines, leading to a chronic stress response because cytokines impair the body’s ability to regulate it — thus leading to depressive symptoms.

Risk of Burnout Can Be Estimated by Analyzing Saliva Samples - Neuroscience News

According to the researchers, compared with the previously used early-morning samples – taken three times after waking at fifteen-minute intervals – the midday and evening saliva samples also provided a much better and more reliable result: “Our current data indicate that people at risk of burnout can be identified from a single saliva sample with almost 100% accuracy, whereas the multiple early-morning sampling involved more laborious methods and produced a much larger range of variation.” Reliable analysis is now possible just four hours after providing the sample and this method even produced better results than analysing stress-related blood parameters. “We will use these results to further reinforce our efforts to prevent stress-related illnesses in collaboration with the stress clinic of the KFA Health and Prevention Center.

How social isolation transforms the brain: A particular neural chemical is overproduced during long-term social isolation, causing increased aggression and fear -- ScienceDaily

Confirming and extending previous observations, the researchers showed that prolonged social isolation leads to a broad array of behavioral changes in mice. These include increased aggressiveness towards unfamiliar mice, persistent fear, and hypersensitivity to threatening stimuli. For example, when encountering a threatening stimulus, mice that have been socially isolated remain frozen in place long after the threat has passed, whereas normal mice stop freezing soon after the threat is removed. These effects are seen when mice are subjected to two weeks of social isolation, but not to short-term social isolation -- 24 hours -- suggesting that the observed changes in aggression and fear responses require chronic isolation.

Stress helps unlearn fear: New findings on extinction learning may prove useful for therapies -- ScienceDaily

"Pharmacological studies have demonstrated that the treatment of anxiety disorders can be improved if the stress hormone cortisol is administered to the patients," says Oliver Wolf. "Our study has produced evidence for an underlying mechanism." Under the umbrella of the Collaborative Research Centre 1280, several research groups from Bochum are planning to investigate if an exposure to stress prior to exposure therapy may improve its efficacy.

Stress and hippocampus

Research in the neurological literature for years has shown changes in the hippocampus when one has experienced long stress – so a release of hormones such as cortisol actually causes damage to the hippocampus. But as it turns out, it may be that damage to the hippocampus also regulates one’s stress response – and that could contribute to the onset of depression. Again, it’s another one of these vicious cycles. We have a list of 100 potentially stressful events – divorce, moving house, losing loved ones, etc. We found that our group of depressed individuals had not experienced more stressful events in their lives – but they had experienced them as more stressful.

Recovery Is All in Your Head | Outside Online

“Interfering with the natural stress response, particularly by prolonging it, is maladaptive,” says Kiely. “The brain and body will only dedicate resources to rebuilding if it doesn’t feel an emergency is around the corner.” In other words, rushing to work and cranking on a deadline report after a challenging morning workout may seriously mitigate positive physical gains.