title: Chronic psychosocial stressors and salivary biomarkers in emerging adults.
abstract: We investigated whole saliva as a source of biomarkers to distinguish individuals who have, and who have not, been chronically exposed to severe and threatening life difficulties. We evaluated RNA and DNA metrics, expression of 37 candidate genes, and cortisol release in response to the Trier Social Stress Test, as well as clinical characteristics, from 48 individuals stratified on chronic exposure to psychosocial stressors within the last year as measured by the Life Events and Difficulties Schedule. Candidate genes were selected based on their differential gene expression ratio in circulating monocytes from a published genome-wide analysis of adults experiencing different levels of exposure to a chronic stressor. In univariate analyses, we observed significantly decreased RNA integrity (RIN) score (P = 0.04), and reduced expression of glucocorticoid receptor-regulated genes (Ps < 0.05) in whole saliva RNA from individuals exposed to chronic stressors, as compared to those with no exposure. In those exposed, we observed significantly decreased BMI (P < 0.001), increased ever-smoking and increased lifetime alcohol abuse or dependence (P ≤ 0.03), and a reduction of cortisol release. In post hoc multivariate analyses including clinical and biospecimen-derived variables, we consistently observed significantly decreased expression of IL8 (Ps<0.05) in individuals exposed, with no significant association to RIN score. Alcohol use disorders, tobacco use, a reduced acute stress response and decreased salivary IL8 gene expression characterize emerging adults chronically exposed to severe and threatening psychosocial stressors.
authors.affiliation: Center for Health Sciences, SRI International, Menlo Park, CA 94025, United States. andrew.bergen@sri.com
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Bergen
authors.forename: Aditi
authors.initials: A
authors.lastname: Mallick
authors.forename: Denise
authors.initials: D
authors.lastname: Nishita
authors.forename: Xin
authors.initials: X
authors.lastname: Wei
authors.forename: Martha
authors.initials: M
authors.lastname: Michel
authors.forename: Aaron
authors.initials: A
authors.lastname: Wacholder
authors.forename: Sean P
authors.initials: SP
authors.lastname: David
authors.forename: Gary E
authors.initials: GE
authors.lastname: Swan
authors.forename: Mark W
authors.initials: MW
authors.lastname: Reid
authors.forename: Anne
authors.initials: A
authors.lastname: Simons
authors.forename: Judy A
authors.initials: JA
authors.lastname: Andrews
mesh_terms: D000328:Adult; D000367:Age Factors; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism*; D002908:Chronic Disease; D005260:Female; D005786:Gene Expression Regulation; D056726:Genetic Association Studies; D006801:Humans; D008297:Male; D046228:Microarray Analysis; D012463:Saliva / Q000378:metabolism*; D013315:Stress, Psychological / Q000235:genetics* / Q000378:metabolism; D054928:Validation Studies as Topic; D055815:Young Adult
chemical_list: D015415:Biomarkers