TY - JOUR A1 - Weidner, Magdalena T. A1 - Lardenoije, Roy A1 - Eijssen, Lars A1 - Mogavero, Floriana A1 - De Groodt, Lilian P. M. T. A1 - Popp, Sandy A1 - Palme, Rupert A1 - Förstner, Konrad U. A1 - Strekalova, Tatyana A1 - Steinbusch, Harry W. M. A1 - Schmitt-Böhrer, Angelika G. A1 - Glennon, Jeffrey C. A1 - Waider, Jonas A1 - van den Hove, Daniel L. A. A1 - Lesch, Klaus-Peter T1 - Identification of cholecystokinin by genome-wide profiling as potential mediator of serotonin-dependent behavioral effects of maternal separation in the amygdala JF - Frontiers in Neuroscience N2 - Converging evidence suggests a role of serotonin (5-hydroxytryptamine, 5-HT) and tryptophan hydroxylase 2 (TPH2), the rate-limiting enzyme of 5-HT synthesis in the brain, in modulating long-term, neurobiological effects of early-life adversity. Here, we aimed at further elucidating the molecular mechanisms underlying this interaction, and its consequences for socio-emotional behaviors, with a focus on anxiety and social interaction. In this study, adult, male Tph2 null mutant (Tph2\(^{-/-}\)) and heterozygous (Tph2\(^{+/-}\)) mice, and their wildtype littermates (Tph2\(^{+/+}\)) were exposed to neonatal, maternal separation (MS) and screened for behavioral changes, followed by genome-wide RNA expression and DNA methylation profiling. In Tph2\(^{-/-}\) mice, brain 5-HT deficiency profoundly affected socio-emotional behaviors, i.e., decreased avoidance of the aversive open arms in the elevated plus-maze (EPM) as well as decreased prosocial and increased rule breaking behavior in the resident-intruder test when compared to their wildtype littermates. Tph2\(^{+/-}\) mice showed an ambiguous profile with context-dependent, behavioral responses. In the EPM they showed similar avoidance of the open arm but decreased prosocial and increased rule breaking behavior in the resident-intruder test when compared to their wildtype littermates. Notably, MS effects on behavior were subtle and depended on the Tph2 genotype, in particular increasing the observed avoidance of EPM open arms in wildtype and Tph2\(^{+/-}\) mice when compared to their Tph2\(^{-/-}\) littermates. On the genomic level, the interaction of Tph2 genotype with MS differentially affected the expression of numerous genes, of which a subset showed an overlap with DNA methylation profiles at corresponding loci. Remarkably, changes in methylation nearby and expression of the gene encoding cholecystokinin, which were inversely correlated to each other, were associated with variations in anxiety-related phenotypes. In conclusion, next to various behavioral alterations, we identified gene expression and DNA methylation profiles to be associated with TPH2 inactivation and its interaction with MS, suggesting a gene-by-environment interaction-dependent, modulatory function of brain 5-HT availability. KW - serotonin KW - maternal separation KW - mouse KW - emotional behavior KW - DNA methylation KW - RNA expression Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201340 VL - 13 ER - TY - JOUR A1 - Gutknecht, Lise A1 - Popp, Sandy A1 - Waider, Jonas A1 - Sommerlandt, Frank M. J. A1 - Göppner, Corinna A1 - Post, Antonia A1 - Reif, Andreas A1 - van den Hove, Daniel A1 - Strekalova, Tatyana A1 - Schmitt, Angelika A1 - Colaςo, Maria B. N. A1 - Sommer, Claudia A1 - Palme, Rupert A1 - Lesch, Klaus-Peter T1 - Interaction of brain 5-HT synthesis deficiency, chronic stress and sex differentially impact emotional behavior in Tph2 knockout mice JF - Psychopharmacology N2 - Rationale While brain serotonin (5-HT) function is implicated in gene-by-environment interaction (GxE) impacting the vulnerability-resilience continuum in neuropsychiatric disorders, it remains elusive how the interplay of altered 5-HT synthesis and environmental stressors is linked to failure in emotion regulation. Objective Here, we investigated the effect of constitutively impaired 5-HT synthesis on behavioral and neuroendocrine responses to unpredictable chronic mild stress (CMS) using a mouse model of brain 5-HT deficiency resulting from targeted inactivation of the tryptophan hydroxylase-2 (Tph2) gene. Results Locomotor activity and anxiety- and depression-like behavior as well as conditioned fear responses were differentially affected by Tph2 genotype, sex, and CMS. Tph2 null mutants (Tph2\(^{−/−}\)) displayed increased general metabolism, marginally reduced anxiety- and depression-like behavior but strikingly increased conditioned fear responses. Behavioral modifications were associated with sex-specific hypothalamic-pituitary-adrenocortical (HPA) system alterations as indicated by plasma corticosterone and fecal corticosterone metabolite concentrations. Tph2\(^{−/−}\) males displayed increased impulsivity and high aggressiveness. Tph2\(^{−/−}\) females displayed greater emotional reactivity to aversive conditions as reflected by changes in behaviors at baseline including increased freezing and decreased locomotion in novel environments. However, both Tph2\(^{−/−}\) male and female mice were resilient to CMS-induced hyperlocomotion, while CMS intensified conditioned fear responses in a GxE-dependent manner. Conclusions Our results indicate that 5-HT mediates behavioral responses to environmental adversity by facilitating the encoding of stress effects leading to increased vulnerability for negative emotionality. KW - Serotonin KW - Tryptophan hydroxylase-2 (Tph2) KW - chronic stress KW - gene-by-environment interaction KW - anxiety KW - fear KW - depression KW - aggression Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-154586 VL - 232 SP - 2429 EP - 2441 ER - TY - JOUR A1 - Bodden, Carina A1 - Richter, S. Helene A1 - Schreiber, Rebecca S. A1 - Kloke, Vanessa A1 - Gerß, Joachim A1 - Palme, Rupert A1 - Lesch, Klaus-Peter A1 - Lewejohann, Lars A1 - Kaiser, Sylvia A1 - Sachser, Norbert T1 - Benefits of adversity?! How life history affects the behavioral profile of mice varying in serotonin transporter genotype JF - Frontiers in Behavioral Neuroscience N2 - Behavioral profiles are influenced by both positive and negative experiences as well as the genetic disposition. Traditionally, accumulating adversity over lifetime is considered to predict increased anxiety like behavior ("allostatic load"). The alternative "mismatch hypothesis" suggests increased levels of anxiety if the early environment differs from the later-life environment. Thus, there is a need for a whole-life history approach to gain a deeper understanding of how behavioral profiles are shaped. The aim of this study was to elucidate the effects of life history on the behavioral profile of mice varying in serotonin transporter (5-HIT) genotype, an established mouse model of increased anxiety-like behavior. For this purpose, mice grew up under either adverse or beneficial conditions during early phases of life. In adulthood, they were further subdivided so as to face a situation that either matched or mismatched the condition experienced so far, resulting in four different life histories. Subsequently, mice were tested for their anxiety-like and exploratory behavior. The main results were: (1) Life history profoundly modulated the behavioral profile. Surprisingly, mice that experienced early beneficial and later escapable adverse conditions showed less anxiety-like and more exploratory behavior compared to mice of other life histories. (2) Genotype significantly influenced the behavioral profile, with homozygous 5-HTT knockout mice displaying highest levels of anxiety-like and lowest levels of exploratory behavior. Our findings concerning life history indicate that the absence of adversity does not necessarily cause lower levels of anxiety than accumulating adversity. Rather, some adversity may be beneficial, particularly when following positive events. Altogether, we conclude that for an understanding of behavioral profiles, it is not sufficient to look at experiences during single phases of life, but the whole life history has to be considered. KW - anxiety-like behavior KW - maternal care KW - dangerous world KW - animal behavior KW - match-mismatch KW - chronic social stress KW - elevated plus-maze KW - 5-HTT KW - life history KW - predictive adaptive response hypothesis KW - developmental plasticity KW - knockout mice KW - environmental enrichment KW - allostatic load Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-143723 VL - 9 IS - 47 ER -