Pituitary adenylate cyclase-activating polypeptide (PACAP or ADCYAP1) und its receptor one (PAC1 or ADCYAP1R1) are upregulated following chronic stress in brain areas implicated in emotional control of behaviour and deficiency of PACAP and PAC1 influence anxiety- and depression like behaviour in preclinical models. In order to elucidate the genetic contribution of PACAP and PAC1 to depression and anxiety disorders, we performed a case-control association analysis of SNPs in the genes PACAP and PAC1 in two unipolar depression samples and one panic disorder sample (PD). Additionally, a quantitative analysis with parameters of the Dex-CRH-Test was done. In the PAC1 gene, 6 SNPs were highly associated with depression. In the analysis of parameters of the Dex-CRH-Test, SNPs in the PAC1 gene were significantly associated with the Area under the curve of ACTH in the PD group. The same set of SNPs was nominally associated with the area under the curve of Cortisol (Cauc) in PD and in the depressed group. In contrast to the study in PTSD patients, no gender-specific effects could be found in the depressed and PD group. In the present study, we first detected significant associations of SNPs in the PAC1 gene with depression. Additionally, interesting genetic effects have been found for parameters of the Dex-CRH-Test suggesting a direct link to the effects of PAC1 in the pituitary.
Posttraumatic stress disorder (PTSD) is triggered by extremely stressful environmental events and characterized by high emotional distress, re-experiencing of trauma, avoidance and hypervigilance. The present study uses polygenic risk scores (PRS) derived from the UK Biobank (UKBB) mega-cohort analysis as part of the PGC PTSD GWAS effort to determine the heritable basis of PTSD in the South Eastern Europe (SEE)-PTSD cohort. We further analyzed the relation between PRS and additional disease-related variables, such as number and intensity of life events, coping, sex and age at war on PTSD and CAPS as outcome variables.Association of PRS, number and intensity of life events, coping, sex and age on PTSD were calculated using logistic regression in a total of 321 subjects with current and remitted PTSD and 337 controls previously subjected to traumatic events but not having PTSD. In addition, PRS and other disease-related variables were tested for association with PTSD symptom severity, measured by the Clinician Administrated PTSD Scale (CAPS) by liner regression. To assess the relationship between the main outcomes PTSD diagnosis and symptom severity, each of the examined variables was adjusted for all other PTSD related variables.The categorical analysis showed significant polygenic risk in patients with remitted PTSD and the total sample, whereas no effects were found on symptom severity. Intensity of life events as well as the individual coping style were significantly associated with PTSD diagnosis in both current and remitted cases. The dimensional analyses showed as association of war-related frequency of trauma with symptom severity, whereas the intensity of trauma yielded significant results independently of trauma timing in current PTSD.The present PRS application in the SEE-PTSD cohort confirms modest but significant polygenic risk for PTSD diagnosis. Environmental factors, mainly the intensity of traumatic life events and negative coping strategies, yielded associations with PTSD both categorically and dimensionally with more significant p-values. This suggests that, at least in the present cohort of war-related trauma, the association of environmental factors and current individual coping strategies with PTSD psychopathology was stronger than the polygenic risk.
Annotation of genes with transcription start sites (TSS) near epigenetic clock CpGs and their expression changes in response to DEX. Gene annotation was based on [43]. (XLSX 26 kb)
Panic disorder is a frequent and disabling mental disorder characterized by recurrent periods or abrupt surges of intense fear or discomfort, the panic attacks. The clinical phenomenology of panic attacks suggests a prominent role of a disturbed stress response regulation in the aetiopathology of this disorder. We summarize the results of challenge tests of the hypothalamus-pituitary-adrenocortical (HPA) axis in panic disorder and give an overview of studies using psychosocial challenge paradigms. The results of HPA axis challenge tests suggest an increased expression of the hypothalamic neuropeptides, but an intact negative feedback inhibition at the level of the pituitary. Psychosocial challenge tests give evidence for dissociation between the subjective stress response and the HPA axis response in panic disorder, which might be the result of an over-focussed self-monitoring leading to an enhanced stress perception despite normal HPA axis activation. We integrated these findings in a cognitive stress control model suggesting that panic disorder patients develop efficient strategies to control the somatic stress response despite a hypothalamic hyperdrive of the HPA axis. To employ these strategies at the right time, patients acquired an enhanced perception of stress symptoms, leading to the reported dissociation of the subjective and HPA axis response. It can be inferred from these findings that cognitive behavioral therapy addressing over-focussed self-monitoring and maladaptive control strategies in combination with pharmacological treatment against over-expression of the hypothalamic neuropeptides should be an effective treatment in severe forms of panic disorder, which corresponds with recent treatment guidelines.
ABSTRACT Huntington’s Disease (HD) is strongly associated with psychiatric symptoms, yet, associations between Huntingtin gene ( HTT ) CAG repeat size variations and psychiatric phenotypes outside the HD complex are still under-investigated. In this genetic case-control study we compared the distribution of HTT CAG repeat sizes in predefined ranges between patients with major depressive disorder (MDD) (n=2136) and anxiety disorders (ANX) (n=493), and healthy controls (CON) (n=1566). We used regression models to study interactions between the alleles and associations with fine-granular clinical phenotypes and basal ganglia structure. HD mutations in the range of incomplete penetrance (36-39 repeats) were not overrepresented in patients. In participants older than 48 years, 13-20 repeats on both HTT alleles were associated with a reduced ANX risk whereas a 13-20|21-26 combination was associated with an increased ANX risk. Post-hoc analyses confirmed a turning point around 21 repeats and trends in the same direction were detected for MDD. The joint patient|CON analysis of the full spectrum of allele combinations confirmed interaction effects and age-dependent allele|risk profiles. A short-by-long interaction effect and an age-dependent negative correlation of the short allele on the nucleus accumbens volume was detected, independently of the diagnostic group. In conclusion, we revealed that HTT CAG repeat sizes of both alleles in the non-HD range modulate the susceptibility for common psychiatric disorders and basal ganglia structure in an age-dependent way, displaying that normal variation of the functionally diverse wildtype huntingtin protein may already impact brain function.