New Explanation For Depression And Chronic Stress | UA Magazine

Major Depressive Disorder and chronic stress are both characterized by atrophy of neurons and loss of synapses (centers of neurotransmission that deliver neural impulses) in specific brain areas. It’s been recently shown that the prefrontal cortex of subjects with Major Depressive Disorder, analyzed postmortem, contains abnormally low expression levels of a protein called mTORC1, which controls protein synthesis during cell growth and synapses remodeling.
In line with this, it was also observed that in rats some antidepressants augment mTORC1 levels, and this is associated with increased synapses formation in the prefrontal cortex. But what controls mTORC1 expression in the brain? And more importantly, would it be possible to manipulate mTORC1 levels therapeutically to rescue neuronal function?

Stress and TORC1

In a study just published in Nature Medicine, Ota and colleagues from Yale University have identified a new mechanism that is at least in part responsible for the brain alterations caused by loss of mTORC1. The scientists focused on a gene called REDD1 whose product is known to inhibit mTORC1 function. They found that in individuals that were affected by Major Depressive Disorder, high levels of REDD1 correlated with low mTORC1 expression, suggesting a possible link between these two molecules.

An integrative review of factors associated with telomere length and implications for biobehavioral research.

Although telomere shortening occurs as a natural part of aging, there is now a robust body of research that suggests that there is a relationship between psychosocial, environmental, and behavioral factors and changes in telomere length. These factors need to be considered when integrating telomere measurement in biobehavioral research studies.
OBJECTIVES:

This article provides a brief summary of the known facts about telomere biology and an integrative review of current human research studies that assessed relationships between psychosocial, environmental, or behavioral factors and telomere length.
METHODS:

An integrative review was conducted to examine human research studies that focused on psychosocial, environmental, and behavioral factors affecting telomere length and telomerase activity using the electronic databases PubMed/Medline and CINAHL from 2003 to the present. In addition to the known individual factors that are associated with telomere length, the results of the integrative review suggest that perceived stress, childhood adversities, major depressive disorder, educational attainment, physical activity, and sleep duration should also be measured.
DISCUSSION:

Multiple factors have been shown to affect telomere length. To advance understanding of the role of telomere length in health and disease risk, it will be important to further elucidate the mechanisms that contribute to telomere shortening.

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