Oxytocin receptor gene methylation in male and female PTSD patients and trauma-exposed controls.

Oxytocin receptor gene (OXTR) DNA-methylation levels have been associated with trauma-exposure, mood- and anxiety disorders, and social processes relevant to posttraumatic stress disorder (PTSD). We hypothesized that OXTR methylation may play a role in the neurobiological underpinnings of PTSD. In the current study, we compared OXTR methylation between PTSD patients (n = 31, 14 females) and trauma-exposed controls (n = 36, 19 females). Additionally, the association between OXTR methylation and PTSD symptom severity and amygdala reactivity to an emotional faces task was assessed, as a neural hallmark of PTSD. DNA-methylation was investigated in the CpG island located at exon 3 of the OXTR, previously associated with OXTR expression. We observed a significant interaction between PTSD-status, sex and CpG-position on methylation levels. Post-hoc testing revealed that methylation levels at two specific CpG-sites were significantly higher in PTSD females compared to female trauma-exposed controls and PTSD males (CpGs Chr3:8809437, Chr3:8809413). No significant differences in methylation were observed between male PTSD patients and controls. Furthermore, within PTSD females, methylation in these CpG-sites was positively associated with anhedonia symptoms and with left amygdala responses to negative emotional faces, although this was no longer significant after stringent correction for multiple-comparisons. Though the modest size of the current sample is an important limitation, we are the first to report on OXTR methylation in PTSD, replicating previously observed (sex-specific) associations of OXTR methylation with other psychiatric disorders.

[Posttraumatic stress disorder: current insights in diagnostics, treatment and prevention]. / Posttraumatische stressstoornis.

- Posttraumatic stress disorder (PTSD) is a psychiatric disorder that may develop after traumatic events.- PTSD is one of the most prevalent psychiatric disorders in the Netherlands, with an estimated lifetime prevalence of 7%.- Recurrent re-experiencing of the traumatic event is the most characteristic PTSD symptom.- Recognition of PTSD may be hampered by the heterogeneous symptomatology, avoidance to talk about the trauma and highly frequent comorbid psychiatric and somatic comorbidity.- Feelings of guilt and shame may also influence reported trauma history.- First choice treatment for PTSD is trauma-focused psychotherapy, which may be combined with pharmacotherapy.- In case of severe acute posttraumatic stress symptoms after a recent trauma, it is recommended to start early trauma-focused psychotherapy.- Neurobiological findings are increasingly applied in novel interventions to improve the treatment and prevention of PTSD.

Salivary Oxytocin and Vasopressin Levels in Police Officers With and Without Post-Traumatic Stress Disorder.

Post-traumatic stress disorder (PTSD) is characterised by symptoms associated with maladaptive fear and stress responses, as well as with social detachment. The neuropeptides oxytocin (OT) and arginine vasopressin (AVP) have been associated with both regulating fear and neuroendocrine stress responsiveness and social behaviour. However, there is only limited evidence for dysregulated peripheral OT and AVP levels in PTSD patients. The present study aimed to investigate basal salivary OT and AVP levels in trauma-exposed male and female police officers with and without PTSD. Saliva samples were collected during rest and OT and AVP levels were determined using a radioimmunoassay. Men and women were analysed separately, having adjusted for differences in trauma history, and for hormonal contraception use in women. The results showed that male PTSD patients had lower basal salivary OT levels, and did not differ in AVP levels compared to male trauma-exposed healthy controls after adjusting for childhood emotional abuse. There were no significant differences in basal salivary OT and AVP levels in women. Our findings indicate potential dysfunctioning of the OT system in male PTSD patients. Future studies are needed to replicate these findings and to further unravel the relationship between the OT and AVP systems, sex, trauma history and PTSD.