Blood and affective markers of stress in Elite Airmen during a preparatory training course: A pilot study

Abstract

In highly stressful environments, individuals with diverging stress-reactivity can perform differently. Identification of blood markers of stress-reactivity is of major significance to help human performance during stress. Candidate transcripts were identified between stressed and non-stressed strains of rats’ blood and brain, and overlapping significant differentially expressed genes were selected. Serum levels of human orthologues of these proteins, in lieu of blood RNA, in addition to classic stress and general clinical markers, were measured in 33 Battlefield Airmen undergoing a 52 day long preparatory training course before their course of initial entry (COIE). Blood samples and factors of affective state, negative valence “Threat” and positive valence “Challenge”, were obtained five times across different days of training which included either routine physical exercise or prolonged and intense physical and mental training. During training, levels of chloride (Cl), dehydroepiandrosterone-sulfate (DHEA-S), creatinine kinase (CK), and total carbon dioxide (TCO2) differed between airmen who subsequently graduated from their COIE and those who did not. Time dependent changes of serum TCO2 and neuropeptide Y (NPY), as well as the affective factor Challenge differed by future graduation status throughout the training. Serum levels of parvin beta (PARVB) correlated with the affective factor Threat, while those of NPY, testosterone, coactosin like F-actin binding protein 1 (COTL1) and C-reactive protein (CRP) correlated with factor Challenge during the extended, intensive periods of training, consistently. These pilot data suggest that the identified panel of blood markers can measure stress responsiveness, which has the potential to advance individualized stress-management strategies.

The Wistar Kyoto Rat: A Model of Depression Traits

“…Blood samples and factors of affective state, negative valence “threat”, and positive valence “challenge”, have been obtained across different days of training after either routine physical exercise or prolonged and intense physical and mental training. As expected, serum cortisol levels differed between individuals with the differing success in coping with the strenuous training [ 111 ]. Furthermore, serum levels of this stress panel correlated significantly with affective measures after the stressfulness of extended training.…”

“…Serum protein levels of human orthologues of these DEGs, in addition to classic stress and general clinical markers, were measured in 33 Battlefield Airmen, during a 52-day long preparatory training course before their course of initial entry [ 111 ]. Blood samples and factors of affective state, negative valence “threat”, and positive valence “challenge”, have been obtained across different days of training after either routine physical exercise or prolonged and intense physical and mental training.…”

The emotional impact of disrupted environmental contexts: Enrichment loss and coping profiles influence stress response recovery in Long–Evans rats

“…Additionally, past research suggests that higher levels of DHEA and DHEA(S) are predictive of emotional resilience 52,53 . For example, higher DHEA levels predicted perseverance and graduation outcomes for an elite airmen training program 54 . Finally, the DHEA:CORT ratio measure utilized in the present study was beneficial in that the relative measure across timepoints is less sensitive to circadian effects than analyses of absolute values of corticosterone and DHEA.…”

“…52,53 For example, higher DHEA levels predicted perseverance and graduation outcomes for an elite airmen training program. 54 Finally, the DHEA:CORT ratio measure utilized in the present study was beneficial in that the relative measure across timepoints is less sensitive to circadian effects than analyses of absolute values of corticosterone and DHEA. Thus, the DHEA:CORT index offers potential as an indicator of an animals' ability to recover to baseline stress hormone levels in an efficient manner that does not result in wear and tear of the affected physiological systems, a response associated with a decreased likelihood of allostatic load and stress-related-illnesses.…”