Physiological

Physiological
Epigenetics refers to changes to the structure of DNA that affect patterns of gene expression without modifying the primary nucleotide sequence. Methylation of cytosine residues within CpG dinucleotides (5-methyl-cytosine) is one of several known epigenetic and a vast literature characterizes CpG sites and/or genomic regions that become either hypermethylated or hypomethylated with increasing age, suggesting a role for DNA methylation in biological aging.
Physiological
Our genes are comprised of DNA, but those DNA genes only influence cellular function, health, and behavior if they are transcribed into RNA, or “expressed.” Only a subset of our ~20,000 genes are actively transcribed in any given cell, and which genes are “on” and “off” determines not only the identity of the cell but its functional capacities and behavior. As such, RNA “transcriptome profiling” has become the dominant method for analyzing the molecular underpinnings of healthy physiology, development, aging, and disease. Research has also found that social and psychological processes can influence RNA profiles. RNA profiling thus provides a useful method for mapping the molecular interface between social and behavioral processes and the biology of health and aging.
Physiological
This summary focuses on the measurement of the hormone cortisol in hair. Hair cortisol provides information regarding longer-term (weeks to months) cortisol exposure levels. We highlight why hair cortisol analysis advances neuroendocrine research for several reasons.
Physiological
There is fairly consistent evidence that stress, both acute and chronic, is related to elevated levels of inflammatory activity despite the fact that iInflammation is a fundamental immune process for maintaining survival in that it serves as the body’s natural response to insult or injury. This summary describes the various options for inflammation in studies of stress.
Physiological
The autonomic nervous system (ANS) functions to mobilize energy and deliver oxygenated-blood to the body. The ANS changes during sleeping and waking states, postural changes, and physical movement. Moreover, ANS changes occur during mental states such as stress, emotion, cognitive, and motivation. This document provides an overview of some of the more commonly used measures in stress studies that can be obtained relatively non-invasively. We describe the process of obtaining ANS responses including technological requirements for lab and field experiments, and the specifics of obtaining, scoring, quantifying, analyzing, and interpreting ANS responses.
Physiological
The hypothalamic-pituitary adrenal (HPA) axis has been proposed to play a key role in stress-health linkages. Thus, interest in the HPA axis has been strong, and has exploded over the past decade with the availability of low cost cortisol measurement in saliva. This allowed cortisol assessment in population-based and epidemiological research, providing valuable evidence on links between salivary cortisol with job stress, trauma, depression, socioeconomic and demographic status, negative health outcomes, metabolic disease, and cancer mortality.
Physiological
Immune cell telomere length has become a common biomarker in health studies because it reliably predicts later onset of several diseases such as cardiovascular disease, it’s mechanisms of disease are understood, and it is easy to measure with blood. It is also associated with the wide range of exposome factors–chemicals, pollution, neighborhood safety, stressor exposures, and lifestyle.