Differential Effects of 5-HTTLPR Genotypes on Inhibition of Negative Emotional Information Following Acute Stress Exposure and Tryptophan Challenge

Abstract

Previous data suggest that a polymorphism at the serotonin (5-HT) transporter gene (5-HTTLPR) may influence stress resilience and stress-related depression symptoms due to interactions between brain 5-HT dysfunction and stress exposure. Although attentional bias for emotional information has been reliably observed in depression, the interaction between 5-HT transporter-linked promoter region (5-HTTLPR), brain 5-HT vulnerability, and acute stress on affective information processing has not yet been investigated. This study examines the effects of tryptophan (TRP) augmentation (indicating 5-HT manipulation) on inhibition of negative emotional information under stress in mainly femalesubjects were tested for mood and inhibition of emotional information in a double-blind, placebo-controlled design before and after stress exposure following TRP manipulation. Stress exposure significantly impaired inhibition of negative affective information only in S 0 /S 0 carriers, whereas L 0 /L 0 carriers even showed increased inhibition of negative information. The S 0 /S 0 allele 5-HTTLPR genotype increases cognitive-attentional bias for negative emotional information under acute stress. As this bias is an important component of depression, this may be a mediating mechanism making S 0 /S 0 -allele carriers more vulnerability for stress-induced depression symptoms. Moreover, current data suggest that L 0 /L 0 -allele genotypes are more resilient, even increasing cognitive emotional (inhibitory) control after stress.

The Impact of Genetics on Physical Resilience and Successful Aging

“…The findings from this study support prior research with young adults in which there was also a significant association between the SLC6A4 gene and resilience, although in our study the focus was on physical resilience versus psychological resilience (Amstadter et al, 2012;Graham et al, 2013;Markus & Raedt, 2011;Verschoor & Markus, 2011). Similarly, our study also supported prior research including older adults that reported no significant association between BDNF, CRHR1, FKBP5, or COMT and resilience (Rana et al, 2014).…”

Higher chronic psychological stress is associated with blunted affective responses to strenuous resistance exercise: RPE, pleasure, pain

“…Efforts should be taken to ascertain factors that may lead to resiliency in the face of stress, such as exercise stage-of-change (Lutz et al, 2010), serotonin (5-HTTLPR) genotypes (Markus & De Raedt, 2011), and utilization of exercise to cope with stress, a factor associated with detached emotional processing (Masters & Ogles, 1998). Finally, there was no control condition or comparison with other modes of exercise, such as aerobic exercise at a matched level of intensity or caloric expenditure.…”

Interaction between the 5-HTTLPR genotype, impact of stressful life events, and trait neuroticism on depressive symptoms in healthy volunteers

“…Specifically, in a prospective longitudinal study, it was reported that individuals carrying the S allele of the 5-HTTLPR polymorphism responded more readily to stressful life events with depression than individuals with the LL genotype. Although a broad range of epidemiological studies replicated the initial findings of Caspi et al (2003) (for a review, see Uher and McGuffin, 2008;Uher and McGuffin, 2010;Karg et al, 2011), and abundant imaging (see Munafo et al, 2008) as well as acute stress exposure studies (Gotlib et al, 2008;Alexander et al, 2009;Dougherty, et al, 2010;Mueller et al, 2010;Way and Taylor, 2010;Markus and De Raedt, 2011) show that the S-allele 5-HTTLPR genotype increasingly promotes stress responsiveness, there also are part-replications and nonreplications (Uher and McGuffin, 2008;Uher and McGuffin, 2010;Karg et al, 2011), Inconsistencies in previous research might be explained by the relative lack of consideration for cognitive-psychological factors that may moderate the stress-depression relationship. According to the generally accepted cognitive vulnerability-transactional stress model of depression (Lazarus and Folkman, 1984), environmental events cause stress and affective changes depending on whether they are appraised as personally relevant (primary appraisal) and whether or not they are evaluated as manageable by (believe in) adequate coping abilities (secondary appraisal) (Brown et al, 1987;Gunthert et al, 1999).…”