Oxytocin receptor gene variation and differential susceptibility to family environment in predicting youth borderline symptoms

Treating depression in patients with borderline personality disorder: clinical clues on the use of antidepressants

Personality disorders (PD) are described as enduring patterns of markedly deviant and pervasive inner experiences and behaviors, with onset in adolescence, which lead to severe distress or impairment. Patients suffering from major depressive disorder (MDD) display higher rates of comorbidity with personality disorders, often complicating the treatment, and worsening the outcomes. Borderline personality disorder (BPD) is the most common of PD and is frequently associated with MDD, with which shares several features. The most part of research agrees on the fact that comorbid BPD in MDD patients quite doubles the poor response to treatments. Moreover, no treatment strategy stands out currently to emerge as more effective in these cases, thus urging the call for the need of new approaches. Herein, we revise the current literature on BPD, its neurobiology and comorbidity with MDD, as well as the more recent treatment strategies used. Then, based on its pharmacology, we propose a possible role of trazodone as a valuable tool to approach comorbid BPD-MDD.

Involvement of oxytocin receptor deficiency in psychiatric disorders and behavioral abnormalities

Oxytocin and its target receptor (oxytocin receptor, OXTR) exert important roles in the regulation of complex social behaviors and cognition. The oxytocin/OXTR system in the brain could activate and transduce several intracellular signaling pathways to affect neuronal functions or responses and then mediate physiological activities. The persistence and outcome of the oxytocin activity in the brain are closely linked to the regulation, state, and expression of OXTR. Increasing evidence has shown that genetic variations, epigenetic modification states, and the expression of OXTR have been implicated in psychiatric disorders characterized by social deficits, especially in autism. Among these variations and modifications, OXTR gene methylation and polymorphism have been found in many patients with psychiatric disorders and have been considered to be associated with those psychiatric disorders, behavioral abnormalities, and individual differences in response to social stimuli or others. Given the significance of these new findings, in this review, we focus on the progress of OXTR's functions, intrinsic mechanisms, and its correlations with psychiatric disorders or deficits in behaviors. We hope that this review can provide a deep insight into the study of OXTR-involved psychiatric disorders.

Potential epigenetic mechanisms in psychotherapy: a pilot study on DNA methylation and mentalization change in borderline personality disorder

Genetic and early environmental factors are interwoven in the etiology of Borderline Personality Disorder (BPD). Epigenetic mechanisms offer the molecular machinery to adapt to environmental conditions. There are gaps in the knowledge about how epigenetic mechanisms are involved in the effects of early affective environment, development of BPD, and psychotherapy response. We reviewed the available evidence of the effects of psychotherapy on changes in DNA methylation and conducted a pilot study in a sample of 11 female adolescents diagnosed with BPD, exploring for changes in peripheral DNA methylation of FKBP5 gene, which encodes for a stress response protein, in relation to psychotherapy, on symptomatology and underlying psychological processes. For this purpose, measures of early trauma, borderline and depressive symptoms, psychotherapy outcome, mentalization, and emotional regulation were studied. A reduction in the average FKBP5 methylation levels was observed over time. Additionally, the decrease in FKBP5 methylation observed occurred only in those individuals who had early trauma and responded to psychotherapy. The results suggest an effect of psychotherapy on epigenetic mechanisms associated with the stress response. The finding that epigenetic changes were only observed in patients with early trauma suggests a specific molecular mechanism of recovery. The results should be taken with caution given the small sample size. Also, further research is needed to adjust for confounding factors and include endocrinological markers and therapeutic process variables.

Oxytocin: An Old Hormone, A Novel Psychotropic Drug And Possible Use In Treating Psychiatric Disorders

BACKGROUND

Oxytocin is a nonapeptide synthesized in the paraventricular and supraoptic nuclei of the hypothalamus. Historically, this molecule has been involved as a key factor in the formation of infant attachment, maternal behavior and pair bonding and, more generally, in linking social signals with cognition, behaviors and reward. In the last decades, the whole oxytocin system has gained a growing interest as it was proposed to be implicated in etiopathogenesis of several neurodevelopmental and neuropsychiatric disorders.

METHODS

With the main goal of an in-depth understanding of the oxytocin role in the regulation of different functions and complex behaviors as well as its intriguing implications in different neuropsychiatric disorders, we performed a critical review of the current state of art. We carried out this work through PubMed database up to June 2021 with the search terms: 1) "oxytocin and neuropsychiatric disorders"; 2) "oxytocin and neurodevelopmental disorders"; 3) "oxytocin and anorexia"; 4) "oxytocin and eating disorders"; 5) "oxytocin and obsessive-compulsive disorder"; 6) "oxytocin and schizophrenia"; 7) "oxytocin and depression"; 8) "oxytocin and bipolar disorder"; 9) "oxytocin and psychosis"; 10) "oxytocin and anxiety"; 11) "oxytocin and personality disorder"; 12) "oxytocin and PTSD".

RESULTS

Biological, genetic, and epigenetic studies highlighted quality and quantity modifications in the expression of oxytocin peptide or in oxytocin receptor isoforms. These alterations would seem to be correlated with a higher risk of presenting several neuropsychiatric disorders belonging to different psychopathological spectra. Collaterally, the exogenous oxytocin administration has shown to ameliorate many neuropsychiatric clinical conditions.

CONCLUSION

Finally, we briefly analyzed the potential pharmacological use of oxytocin in patient with severe symptomatic SARS-CoV-2 infection due to its anti-inflammatory, anti-oxidative and immunoregulatory properties.

The Relationship Between the Oxytocin Level and Rejection Sensitivity, Childhood Traumas, and Attachment Styles in Borderline Personality Disorder

OBJECTIVE

In this study, it is aimed to investigate the relationship between the oxytocin level and the rejection sensitivity, childhood mental traumas, and attachment styles in patients diagnosed with borderline personality disorder (BPD).

METHODS

Participants between the ages of 18-30 were included in the study. The patient group consists of 31 participants and the healthy control group consists of 31 participants. Sociodemographic/Clinical Variables Questionnaire, Relationship Scales Questionnaire, Rejection Sensitivity Questionnaire and Childhood Trauma Questionnaire were administered to the participants included in the study. Serum oxytocin levels of the participants were measured using the Elisa method.

RESULTS

The oxytocin levels were found to be significantly lower in patients with BPD than in healthy control subjects, whereas the rejection sensitivity and childhood traumas were found to be significantly higher. No difference was found between the patient and control groups in terms of attachment styles, yet it was determined that there may be differences between the oxytocin levels of the BPD patients according to the attachment styles the patients have.

CONCLUSION

In conclusion, the findings of this study revealed that the rejection sensitivity in BPD patients is not associated with oxytocin levels and childhood traumas, indicating the need to assess the BPD patients in terms of other biopsychosocial factors related to the etiopathogenesis of BPD.

Borderline Personality Disorder: Risk Factors and Early Detection

Personality disorders (PDs) exert a great toll on health resources, and this is especially true for borderline personality disorder (BPD). As all PDs, BPD arises during adolescence or young adulthood. It is therefore important to detect the presence of this PD in its earlier stages in order to initiate appropriate treatment, thus ameliorating the prognosis of this condition. This review aims to highlight the issues associated with BPD diagnosis in order to promote its early detection and treatment. To do so, we conducted a search on PubMed database of current evidence regarding BPD early diagnosis, focusing on risk factors, which represent important conditions to assess during young patient evaluation, and on diagnostic tools that can help the clinician in the assessment process. Our findings show how several risk factors, both environmental and genetic/neurobiological, can contribute to the onset of BPD and help identify at-risk patients who need careful monitoring. They also highlight the importance of a careful clinical evaluation aided by psychometric tests. Overall, the evidence gathered confirms the complexity of BDP early detection and its crucial importance for the outcome of this condition.

An interaction between early threat exposure and the oxytocin receptor in females: Disorder-specific versus general risk for psychopathology and social-emotional mediators

Early threat exposure is a transdiagnostic risk factor for psychopathology, and evidence suggests that genetic variation in the oxytocin receptor (OXTR) moderates this association. However, it is unclear if this gene-by-environment (G×E) interaction is tied to unique risk for disorder-specific outcomes or instead increases shared risk for general psychopathology. Moreover, little is known about how this G×E interaction increases risk. The current study utilized a prospective, longitudinal sample of females (n = 2,020) to examine: (a) whether the interaction between early threat exposure and OXTR variation (rs53576, rs2254298) confers risk for disorder-specific outcomes (depression, anxiety, borderline and antisocial personality disorders) and/or general psychopathology in early adulthood; and (b) whether social-emotional deficits (emotion dysregulation, callousness, attachment quality) during adolescence constitute mediating mechanisms. Consistent with hypotheses, the interactive effects of early threat exposure and OXTR variation (rs53576) predicted general psychopathology, with threat-exposed women carrying at least one copy of the rs53576 A-allele at greatest risk. This interaction was mediated via emotional dysregulation in adolescence, with threat-exposed A-allele carriers demonstrating greater emotion dysregulation, and greater emotion dysregulation predicting general psychopathology in early adulthood. Findings suggest that this G×E places women at risk for a broad range of psychopathology via effects on emotion dysregulation.

Role of Oxytocin in the Pathogenesis and Modulation of Borderline Personality Disorder: A Review

Borderline personality disorder (BPD) is a serious psychiatric condition characterized by dysfunctional relations, abnormal social behavior, and high morbidity. Many studies have implicated abnormal oxytocinergic system as a causative factor of behavioral dysregulation in BPD patients. The objective of this review is to provide a comprehensive analysis of the association of oxytocin with the pathogenesis of BPD and its possible role as a therapeutic agent. Our review indicates that a combination of genetic and environmental factors causes BPD patients to have lower baseline levels of oxytocin, leading to increased activation of the amygdala. This results in defective cognition of social stimuli, leading to abnormal behaviors like affective instability, unresolved attachment, and emotional dysregulation. Clinical trials conducted on BPD patients using intranasal oxytocin have shown both prosocial and trust-lowering effects. The effects of oxytocin depend upon various patient characteristics like the history of childhood trauma and the nature of attachment. Even though evidence of oxytocin's role in modulating behavior in BPD patients already exists, further studies are required to more clearly elaborate on this role to fully explore oxytocin's potential as a therapeutic agent.

Oxytocin Receptor Gene (OXTR) and Childhood Adversity Influence Trust

Early-life environments have been associated with various social behaviors, including trust, in late adolescence and adulthood. Given that the oxytocin receptor gene polymorphism (OXTR rs53576) moderates the impact of childhood experience on social behaviors, in the present study, we examined the main effect of childhood adversity through a self-report measure and its interactions with OXTR rs53576 on general trust among 203 Japanese and 200 European Canadian undergraduate students. After controlling for the effect of culture, the results indicated that childhood adversity had a negative association with general trust, and that OXTR rs53576 moderated the impact of childhood adversity on general trust. Specifically, the negative association between childhood adversity and general trust is only significant among homozygote A-allele carriers. These findings demonstrated that OXTR rs53576 moderated the relations between childhood experiences and social functioning in early adulthood.

Oxytocin receptor gene, childhood maltreatment and borderline personality disorder features among male inmates in China

BACKGROUND

Borderline personality disorder (BPD) is caused by a variety of biological and environmental factors. Accumulating evidence suggests that childhood maltreatment is a risk environmental factor in the development of BPD, but research on the genetic pathology of BPD is still in its early stages, and very little is known about the oxytocin receptor (OXTR) gene. The purpose of this study is to further explore the interactive effects between OXTR gene polymorphisms and childhood maltreatment on BPD risk.

METHODS

Among the 1804 Chinese Han male inmates, 765 inmates who had BPD or antisocial personality disorder (ASPD) or highly impulsive or violent crime were considered as high-risk inmates and included in this study. Childhood maltreatment, BPD, antisocial personality disorder (ASPD) and impulsivity were measured by self-reported questionnaires. Peripheral venous blood was collected for the genotype test.

RESULTS

Analyses revealed that the BP group (inmates with BPD features) had higher rs53576 AA genotype frequency and rs237987 AA genotype frequency than the non-BP group, while the statistical significances were lost after Bonferroni correction. Total childhood maltreatment score, emotional abuse and neglect could positively predict BPD risk. Among the high-risk samples, rs53576 GG genotype carriers had higher BPD scores at higher levels of physical abuse and sexual abuse and had lower BPD scores at lower levels of physical abuse and sexual abuse.

CONCLUSIONS

The findings suggest that the interaction between OXTR gene variations and childhood maltreatment is an important mechanism for the development of BPD. The moderating role of the OXTR gene provides evidence for gene plasticity.

A learning theory of attachment: Unraveling the black box of attachment development

Attachment is an inborn behavioral system that is biologically driven and essential for survival. During child development, individual differences in (in)secure attachment emerge. The development of different attachment behaviors has been traditionally explained as a process during which experiences with (lack of) responsive and supportive care are internalized into working models of attachment. However, this idea has been criticized for being vague and even untestable. With the aim of unraveling this black box, we propose to integrate evidence from conditioning research with attachment theory to formulate a Learning Theory of Attachment. In this review, we explain how the development of individual differences in attachment security at least partly follows the principles of classical and operant conditioning. We combine observed associations between attachment and neurocognitive and endocrinological (cortisol, oxytocin, and dopamine) processes with insights in conditioning dynamics to explain the development of attachment. This may contribute to the explanation of empirical observations in attachment research that are insufficiently accounted for by traditional attachment theory.

Adult attachment anxiety moderates the relation between self-reported childhood maltreatment and borderline personality disorder features

Childhood maltreatment is one of many risk factors for borderline personality disorder (BPD). However, not all individuals with BPD report histories of childhood maltreatment. Therefore, it is necessary to identify factors that contextualize the relation between childhood maltreatment and BPD features. With its emphasis on the developmental origins of emotion regulation, attachment theory provides a useful framework to understand how people are differentially affected by early life stress. The present study examined self-reported adult attachment as a moderator in the relation between childhood maltreatment and BPD features in a large undergraduate sample (n = 1 033). Attachment anxiety, but not attachment avoidance, moderated the relation between childhood maltreatment and BPD features, and this relation was non-significant among participants low (-1 standard deviation) in attachment anxiety. These results support the hypothesis that secure attachment in adulthood may buffer against the otherwise deleterious effects of distal risk factors on personality pathology. Future research should continue to examine this question across risk factors and across disorders. Furthermore, we suggest that researchers who have historically examined attachment as a mediator cross-sectionally should re-examine their data for evidence of a moderation effect. © 2019 John Wiley & Sons, Ltd.

Differential Susceptibility to the Environment and Borderline Personality Disorder

Evolutionary models of psychopathology can shed light on gene-environment interactions. Differential susceptibility to the environment means that heritable traits can have positive or negative effects, depending on environmental context. Thus, traits that increase risk for mental disorders when the environment is negative can be adaptive when the environment is positive. This model can be applied to borderline personality disorder, with predictors such as emotional dysregulation and impulsivity seen as temperamental variations leading to negative effects in an unfavorable environment but to positive effects in a favorable environment. This model may also be useful in conceptualizing the mechanisms of effective therapy for borderline personality disorder.

Interaction effect of oxytocin receptor (OXTR) rs53576 genotype and maternal postpartum depression on child behavioural problems

Previous studies have reported interaction effects of oxytocin receptor genotype (rs53576) and environmental factors on mental health in youth. However, the findings are mixed, especially regarding the type of allele (i.e., A vs. G), and it remains unanswered whether such an interaction presents at an early stage of development. Thus, using a unique longitudinal birth cohort sample in Japan (n = 568), we examined whether there was an effect of the interaction between the OXTR rs53576 genotype and maternal postpartum depression, as an environmental risk, on behavioural problems in children. Child behavioural problems (internalising and externalising problems) were ascertained using the Strengths and Difficulties Questionnaire when children were 6 years old. Maternal postpartum depression was measured using the Edinburgh Postnatal Depression Scale when children were at 2 months and 10 months of age. The results revealed a significant effect in the interaction between OXTR rs53576 genotype and maternal postpartum depression on externalising problems in children with AA genotype (β = 0.136, 95% CI 0.032 to 0.240), but not in those with GG/GA genotype. This indicates that an interaction of vulnerable genotypes (i.e., A allele of OXTR rs53576) with an environmental burden (i.e. maternal postpartum depression) may be one of the potential elements that predisposes the infant to developing behavioural problems early in life. Hence, special attention needs to be paid to children exposed to environmental risks such as maternal postpartum depression, to facilitate the provision of appropriate care.

Borderline personality disorder, trauma, and the hypothalamus-pituitary-adrenal axis

Borderline personality disorder (BPD) is a complex psychiatric illness for which treatment poses a significant challenge due to limited effective pharmacologic treatments, and under-resourced psychological interventions. BPD is one of the most stigmatized conditions in psychiatry today, but can be understood as a modifiable, neurodevelopmental disorder that arises from maladaptive responses to trauma and stress. Stress susceptibility and reactivity in BPD is thought to mediate both the development and maintenance of BPD symptomatology, with trauma exposure considered an early life risk factor of development, and acute stress moderating symptom trajectory. An altered stress response has been characterized in BPD at the structural, neural, and neurobiological level, and is believed to underlie the maladaptive behavioral and cognitive symptomatology presented in BPD. The endocrine hypothalamus-pituitary-adrenal (HPA) axis represents a key stress response system, and growing evidence suggests it is dysfunctional in the BPD patient population. This theoretical review examines BPD in the context of a neurodevelopmental stress-related disorder, providing an overview of measurements of stress with a focus on HPA-axis measurement. Potential confounding factors associated with measurement of the HPA system are discussed, including sex and sex hormones, genetic factors, and the influence of sample collection methods. HPA-axis dysfunction in BPD largely mirrors findings demonstrated in post-traumatic stress disorder and may represent a valuable neuroendocrine target for diagnostic or treatment response biomarkers, or for which novel treatments can be investigated.

Early Detection and Outcome in Borderline Personality Disorder

Borderline personality disorder (BPD) is a severe and heterogeneous mental disorder that is known to have the onset in young age, often in adolescence. For this reason, it is of fundamental importance to identify clinical conditions of childhood and adolescence that present a high risk to evolve in BPD. Investigations indicate that early borderline pathology (before 19 years) predict long-term deficits in functioning, and a higher percentage of these patients continue to present some BPD symptoms up to 20 years. There is a general accordance among investigators that good competence in both childhood and early adulthood is the main predictive factor of excellent recovery in BPD patients. Some authors suggest that specific childhood personality traits can to be considered precursors of adult BPD, as well as some clinical conditions: disruptive behaviours, disturbance in attention and emotional regulation, conduct disorders, substance use disorders, and attention-deficit-hyperactivity disorder. Unfortunately, diagnosis and treatment of BPD is usually delayed, also because some clinicians are reluctant to diagnose BPD in younger individuals. Instead, the early identification of BPD symptoms have important clinical implications in terms of precocious intervention programs, and guarantees that young people with personality disorders obtain appropriate treatments. This review is aimed to collect the current evidences on early risk and protective factors in young people that may predict BPD onset, course, and outcome.

The Neurobiology of Borderline Personality Disorder

This article reviews the most salient neurobiological information available about borderline personality disorder (BPD) and presents a theoretic model for what lies at the heart of BPD that is grounded in those findings. It reviews the heritability, genetics, and the biological models of BPD, including the neurobiology of affective instability, impaired interoception, oxytocin and opiate models of poor attachment or interpersonal dysfunction, and structural brain imaging over the course of development in BPD; and posits that the core characteristic of BPD may be an impairment in emotional interoception or alexithymia.

A Neuroscience-Oriented Research Approach to Borderline Personality Disorder

Traditionally, the study of personality disorders had been based on psychoanalytic or behavioral models. Over the past two decades, there has been an emerging neuroscience model of borderline personality disorder (BPD) grounded in the concept of BPD as a condition in which dysfunctional neural circuits underlie its pathological dimensions, some of which include emotion dysregulation (broadly encompassing affective instability, negative affectivity, and hyperarousal), abnormal interpersonal functioning, and impulsive aggression. This article, initiated at a joint Columbia University- Cornell University Think Tank on BPD with representation from the Icahn School of Medicine at Mount Sinai, suggests how to advance research in BPD by studying the dimensions that underlie BPD in addition to studying the disorder as a unitary diagnostic entity. We suggest that linking the underlying neurobiological abnormalities to behavioral symptoms of the disorder can inform a research agenda to better understand BPD with its multiple presentations.

Oxytocin receptors (OXTR) and early parental care: An interaction that modulates psychiatric disorders

Oxytocin plays an important role in the modulation of social behavior in both typical and atypical contexts. Also, the quality of early parental care sets the foundation for long-term psychosocial development. Here, we review studies that investigated how oxytocin receptor (OXTR) interacts with early parental care experiences to influence the development of psychiatric disorders. Using Pubmed, Scopus and PsycInfo databases, we utilized the keyword "OXTR" before subsequently searching for specific OXTR single nucleotide polymorphisms (SNPs), generating a list of 598 studies in total. The papers were catalogued in a database and filtered for gene-environment interaction, psychiatric disorders and involvement of parental care. In particular, rs53576 and rs2254298 were found to be significantly involved in gene-environment interactions that modulated risk for psychopathology and the following psychiatric disorders: disruptive behavior, depression, anxiety, eating disorder and borderline personality disorder. These results illustrate the importance of OXTR in mediating the impact of parental care on the emergence of psychopathology.

Please Don't Leave Me-Separation Anxiety and Related Traits in Borderline Personality Disorder

PURPOSE OF REVIEW

In light of the apparent symptomatic resemblance of separation anxiety disorder (SAD) symptoms on the one hand and abandonment fears, anxiousness, and separation insecurity central to borderline personality disorder (BPD) on the other hand, a comprehensive overview of separation anxiety and related traits in BPD is provided.

RECENT FINDINGS

Epidemiological, environmental, psychological, and neurobiological data connecting BPD to separation events, feelings of loneliness, insecure attachment styles, dimensional separation anxiety as well as SAD per se suggest a partly shared etiological pathway model underlying BPD and SAD. Differential diagnostic aspects and implications for treatment are discussed, highlighting separation anxiety as a promising transdiagnostic target for specific psychotherapeutic and pharmacological treatment approaches in BPD. This innovative angle on cross-disorder symptomatology might carry potential for novel preventive and therapeutic avenues in clinical practice by guiding the development of interventions specifically targeting separation anxiety and attachment-related issues in BPD.

Current Knowledge on Gene-Environment Interactions in Personality Disorders: an Update

PURPOSE OF REVIEW

We review the existing literature on gene-environment interactions (G×E) and epigenetic changes primarily in borderline personality disorder (BPD) but also in antisocial, schizotypal, and avoidant personality disorders.

RECENT FINDINGS

Research supports that susceptibility genes to BPD or its underlying traits may be expressed under certain environmental conditions such as physical or childhood sexual abuse. Epigenetic modifications of neurodevelopment- and stress-related genes are suggested to underlie the relationship between early life adversary and borderline personality disorder. Only limited studies have investigated the role of gene-environment interactions and epigenetic changes in the genesis of antisocial, schizotypal, and avoidant personality disorders. Considering the lack of pharmacological treatment for most personality disorders, the emerging evidence on the critical role of G×E and epigenetic changes in the genesis of personality disorders could help develop more biologically oriented therapeutic approaches. Future studies should explore the potential of this new therapeutic dimension.

Borderline personality disorder

Caretakers are often intimidated or alienated by patients with borderline personality disorder (BPD), compounding the clinical challenges posed by the severe morbidity, high social costs and substantial prevalence of this disorder in many health-care settings. BPD is found in ∼1.7% of the general population but in 15-28% of patients in psychiatric clinics or hospitals and in a large proportion of individuals seeking help for psychological problems in general health facilities. BPD is characterized by extreme sensitivity to perceived interpersonal slights, an unstable sense of self, intense and volatile emotionality and impulsive behaviours that are often self-destructive. Most patients gradually enter symptomatic remission, and their rate of remission can be accelerated by evidence-based psychosocial treatments. Although self-harming behaviours and proneness to crisis can decrease over time, the natural course and otherwise effective treatments of BPD usually leave many patients with persistent and severe social disabilities related to depression or self-harming behaviours. Thus, clinicians need to actively enquire about the central issues of interpersonal relations and unstable identity. Failure to correctly diagnose patients with BPD leads to misleading pharmacological interventions that rarely succeed. Whether the definition of BPD should change is under debate that is linked to not fully knowing the nature of this disorder.

The OXTR Single-Nucleotide Polymorphism rs53576 Moderates the Impact of Childhood Maltreatment on Empathy for Social Pain in Female Participants: Evidence for Differential Susceptibility

Previous research has associated genetic variations of the oxytocin receptor with individual differences in human social behavior. Specifically, homozygous carriers of the G-allele of the single nucleotide polymorphism rs53576 have been reported to display more trust, empathy, and prosocial behavior and were less sensitive toward stress and maltreatment during childhood when compared to A-allele carriers. With regard to Borderline Personality Disorder (BPD), a psychiatric condition that is often associated with the experience of childhood adversity, it has been suggested that A-allele carriers are more vulnerable to developing psychopathological signs and symptoms. In the present study we investigated whether childhood trauma, as assessed by the Childhood Trauma Questionnaire (CTQ), affects empathy for somatic and psychological pain, and how this is moderated by genotype, in a sample of 302 individuals (148 of whom were diagnosed with BPD). We found a three-way interaction between genotype, group and pain condition. Posthoc comparisons revealed that patients with BPD carrying at least one A-allele, rated psychological pain as more intense compared to controls, whereas no difference between groups emerged in GG homozygotes. Moreover, a moderating effect of genotype appeared on the impact of childhood trauma on empathy for psychological pain. In addition, a positive correlation of CTQ scores and empathy appeared only in A-allele carriers (GA + AA), independent of diagnosis. Together, A-allele carriers, especially those with BPD, seemed to be responsive to the impact of adversity on empathy-for-pain, while GG homozygotes were not, which is compatible with the idea of differential susceptibility.

How Do Stress Exposure and Stress Regulation Relate to Borderline Personality Disorder?

Borderline personality disorder (BPD) is a severe and frequent disorder characterized by a pervasive pattern of instability affecting impulse control, emotional regulation, cognitive processing, self-image and interpersonal relationships. Patients’ personal histories are often marked by stressful or traumatic experiences, either unique or repeated. Moreover, while clinical signs of the disorder include both chronic and acute features, acute features are mostly triggered by acute stressful situations. Such features include transient cognitive distortion, intense anger, uncontrollable impulsivity, and self-harm behavior – including suicide – and contribute to the burden of the disease. In this paper, we review the various aspects (epidemiological, clinical, and physiological) contributing to the relationship between BDP and stress. In particular, we explore the statistical association between stress exposure and the emergence of BPD while taking into account other psychopathologies, such as post-traumatic stress disorder. Then, the different aspects of stress responses (namely, the phenomenological, behavioral, hormonal, neuro-vegetative and neural responses) are reviewed in BPD patients. Pathophysiological hypotheses are formulated to explain the differences in responses between BPD patients and healthy subjects and their relation to BPD symptoms. Although the pathogenesis remains uncertain, our conclusions seem to reflect a specific biological and neural pattern of altered stress perception and regulation in BPD.

Differential susceptibility effects of oxytocin gene (OXT) polymorphisms and perceived parenting on social anxiety among adolescents

Social anxiety is one of the most commonly reported mental health problems among adolescents, and it has been suggested that parenting style influences an adolescent's level of anxiety. A context-dependent effect of oxytocin on human social behavior has been proposed; however, research on the oxytocin gene (OXT) has mostly been reported without considering contextual factors. This study investigated the interactions between parenting style and polymorphic variations in the OXT gene in association with social anxiety symptoms in a community sample of adolescents (n = 1,359). Two single nucleotide polymorphisms linked to OXT, rs4813625 and rs2770378, were genotyped. Social anxiety and perceived parenting style were assessed by behavioral questionnaires. In interaction models adjusted for sex, significant interaction effects with parenting style were observed for both variants in relation to social anxiety. The nature of the interactions was in line with the differential susceptibility framework for rs4813625, whereas for rs2770378 the results indicated a diathesis–stress type of interaction. The findings may be interpreted from the perspective of the social salience hypothesis of oxytocin, with rs4813625 affecting social anxiety levels along a perceived unsafe–safe social context dimension.

OXTR polymorphism in depression and completed suicide-A study on a large population sample

In the light of contradictory results concerning OXTR polymorphism rs53576 and depression, we decided to verify the potential association between the two on 1) a large, ethnically homogenous sample of 1185 individuals who completed the Beck Depression Inventory (BDI), as well as on 2) a sample of 763 suicide victims. In the population sample, AA males showed significantly lower BDI scores (p=0.005, p_cor=0.030). Exploratory analyses suggested that this effect was limited to a subgroup within 0-9 BDI score range (p=0.0007, U-Mann Whitney test), whereas no main effect on depressive symptoms (BDI>9) was found. In the suicide sample no association with rs53576 genotype was present. Exploratory analyses in suicides revealed higher blood alcohol concentration (BAC) among AA than GG/GA males (p=0.014, U-Mann Whitney test). Our results show that the OXTR rs53576 variant modulates the mood in male individuals and may positively correlate with alcohol intake among male suicides, but is not associated with suicide or depression. The study adds to the growing knowledge on rs53576 genotype characteristics.

Oxytocin and Borderline Personality Disorder

Borderline personality disorder (BPD) is a prevalent and severe mental disorder with affect dysregulation, impulsivity, and interpersonal dysfunction as its core features. Up to now, six studies have been performed to investigate the role of oxytocin in the pathogenesis of BPD. While a beneficial effect of oxytocin on threat processing and stress responsiveness was found, other studies using an oxytocin challenge design presented with rather heterogeneous results. Future studies have to include a sufficiently large sample of patients, control for gender, and focus on mechanisms known to be related to aversive early life experiences.

Oxytocin pathways in the intergenerational transmission of maternal early life stress

Severe stress in early life, such as childhood abuse and neglect, constitutes a major risk factor in the etiology of psychiatric disorders and somatic diseases. Importantly, these long-term effects may impact the next generation. The intergenerational transmission of maternal early life stress (ELS) may occur via pre-and postnatal pathways, such as alterations in maternal-fetal-placental stress physiology, maternal depression during pregnancy and postpartum, as well as impaired mother-offspring interactions. The neuropeptide oxytocin (OT) has gained considerable attention for its role in modulating all of these assumed transmission pathways. Moreover, central and peripheral OT signaling pathways are highly sensitive to environmental exposures and may be compromised by ELS with implications for these putative transmission mechanisms. Together, these data suggest that OT pathways play an important role in the intergenerational transmission of maternal ELS in humans. By integrating recent studies on gene-environment interactions and epigenetic modifications in OT pathway genes, the present review aims to develop a conceptual framework of intergenerational transmission of maternal ELS that emphasizes the role of OT.

Attachment style and oxytocin receptor gene variation interact in influencing social anxiety

OBJECTIVES

Social anxiety has been suggested to be promoted by an insecure attachment style. Oxytocin is discussed as a mediator of trust and social bonding as well as a modulator of social anxiety. Applying a gene-environment (G × E) interaction approach, in the present pilot study the main and interactive effects of attachment styles and oxytocin receptor (OXTR) gene variation were probed in a combined risk factor model of social anxiety in healthy probands.

METHODS

Participants (N = 388; 219 females, 169 males; age 24.7 ± 4.7 years) were assessed for anxiety in social situations (Social Phobia and Anxiety Inventory) depending on attachment style (Adult Attachment Scale, AAS) and OXTR rs53576 A/G genotype.

RESULTS

A less secure attachment style was significantly associated with higher social anxiety. This association was partly modulated by OXTR genotype, with a stronger negative influence of a less secure attachment style on social anxiety in A allele carriers as compared to GG homozygotes.

CONCLUSIONS

The present pilot data point to a strong association of less secure attachment and social anxiety as well as to a gene-environment interaction effect of OXTR rs53576 genotype and attachment style on social anxiety possibly constituting a targetable combined risk marker of social anxiety disorder.

Youth temperament, harsh parenting, and variation in the oxytocin receptor gene forecast allostatic load during emerging adulthood

An association has been found between receipt of harsh parenting in childhood and adult health problems. However, this research has been principally retrospective, has treated children as passive recipients of parental behavior, and has overlooked individual differences in youth responsivity to harsh parenting. In a 10-year multiple-wave prospective study of African American families, we addressed these issues by focusing on the influence of polymorphisms in the oxytocin receptor gene (OXTR), variants of which appear to buffer or amplify responses to environmental stress. The participants were 303 youths, with a mean age of 11.2 at the first assessment, and their parents, all of whom were genotyped for variations in the rs53576 (A/G) polymorphism. Teachers rated preadolescent (ages 11 to 13) emotionally intense and distractible temperaments, and adolescents (ages 15 and 16) reported receipt of harsh parenting. Allostatic load was assessed during young adulthood (ages 20 and 21). Difficult preadolescent temperament forecast elevated receipt of harsh parenting in adolescence, and adolescents who experienced harsh parenting evinced high allostatic load during young adulthood. However, these associations emerged only among children and parents who carried A alleles of the OXTR genotype. The results suggest the oxytocin system operates along with temperament and parenting to forecast young adults' allostatic load.

Oxytocin receptor polymorphism and childhood social experiences shape adult personality, brain structure and neural correlates of mentalizing

INTRODUCTION

The oxytocin system is involved in human social behavior and social cognition such as attachment, emotion recognition and mentalizing (i.e. the ability to represent mental states of oneself and others). It is shaped by social experiences in early life, especially by parent-infant interactions. The single nucleotid polymorphism rs53576 in the oxytocin receptor (OXTR) gene has been linked to social behavioral phenotypes.

METHOD

In 195 adult healthy subjects we investigated the interaction of OXTR rs53576 and childhood attachment security (CAS) on the personality traits "adult attachment style" and "alexithymia" (i.e. emotional self-awareness), on brain structure (voxel-based morphometry) and neural activation (fMRI) during an interactive mentalizing paradigm (prisoner's dilemma game; subgroup: n=163).

RESULTS

We found that in GG-homozygotes, but not in A-allele carriers, insecure childhood attachment is - in adulthood - associated with a) higher attachment-related anxiety and alexithymia, b) higher brain gray matter volume of left amygdala and lower volumes in right superior parietal lobule (SPL), left temporal pole (TP), and bilateral frontal regions, and c) higher mentalizing-related neural activity in bilateral TP and precunei, and right middle and superior frontal gyri. Interaction effects of genotype and CAS on brain volume and/or function were associated with individual differences in alexithymia and attachment-related anxiety. Interactive effects were in part sexually dimorphic.

CONCLUSION

The interaction of OXTR genotype and CAS modulates adult personality as well as brain structure and function of areas implicated in salience processing and mentalizing. Rs53576 GG-homozygotes are partially more susceptible to childhood attachment experiences than A-allele carriers.

Borderline Personality Disorder: Why 'fast and furious'?

The term 'Borderline Personality Disorder' (BPD) refers to a psychiatric syndrome that is characterized by emotion dysregulation, impulsivity, risk-taking behavior, irritability, feelings of emptiness, self-injury and fear of abandonment, as well as unstable interpersonal relationships. BPD is not only common in psychiatric populations but also more prevalent in the general community than previously thought, and thus represents an important public health issue. In contrast to most psychiatric disorders, some symptoms associated with BPD may improve over time, even without therapy, though impaired social functioning and interpersonal disturbances in close relationships often persist. Another counterintuitive and insufficiently resolved question is why depressive symptoms and risk-taking behaviors can occur simultaneously in the same individual. Moreover, there is an ongoing debate about the nosological position of BPD, which impacts on research regarding sex differences in clinical presentation and patterns of comorbidity.In this review, it is argued that many features of BPD may be conceptualized within an evolutionary framework, namely behavioral ecology. According to Life History Theory, BPD reflects a pathological extreme or distortion of a behavioral 'strategy' which unconsciously aims at immediate exploitation of resources, both interpersonal and material, based on predictions shaped by early developmental experiences. Such a view is consistent with standard medical conceptualizations of BPD, but goes beyond classic 'deficit'-oriented models, which may have profound implications for therapeutic approaches.

On the role of oxytocin in borderline personality disorder

OBJECTIVES

Interpersonal dysfunction is central to borderline personality disorder (BPD). Recent research has focused on the role of oxytocin (OT) in BPD, particularly regarding associations of OT activity with symptoms, genetic polymorphisms of the oxytocin receptor coding gene (OXTR) in BPD, and experimental modification of interpersonal core problems of patients with BPD such as hypervigilance towards threat detection, mistrust, and non-verbal behaviour during social interaction by intranasal application of OT.

METHODS

A literature ('medline') review was performed using the keywords 'oxytocin' and 'borderline personality disorder'. Secondary literature on trauma and attachment in relation to OT was also considered relevant.

RESULTS

Together, findings suggest that in BPD OT is associated with enhanced defensive mechanisms and avoidance behaviour. Moreover, gene-environment interaction concerning polymorphic variations of the OXTR gene and childhood adversity in BPD suggests that these genes convey developmental flexibility or 'differential susceptibility' to environmental contingencies, whereby BPD resides at the poor outcome end of the spectrum.

CONCLUSIONS

In view of the conflicting literature, it needs to be studied carefully whether OT can serve as a therapeutic agent given adjunct to psychotherapy in BPD. More research about the role of OT is also required with regard to the prevention of the non-genetic intergenerational transmission of BPD. Clarifying the role of OT in BPD may also benefit from research in non-human animals targeting the interaction between early adversity and OT availability more directly.

PRACTITIONER POINTS

The study of oxytocin can contribute to the understanding of the neurobiology of borderline personality disorder. Oxytocin is critically involved in attachment security, and methylation of the oxytocin receptor may play a role in the epigenetic modulation of early adversity. The intranasal application of oxytocin may be a useful therapeutic adjunct to psychotherapy. Insecure attachment and childhood adversity may produce differential neurobiological effects on the oxytocinergic system in borderline personality disorder. There is insufficient knowledge of how oxytocin interacts with vasopressin, testosterone, dopamine, and serotonin, which are also important key players in the experience of social reward and stress responsivity. It is unclear whether or not oxytocin could be beneficial in preventing the intergenerational (non-genetic) transmission of borderline personality traits.

Personality disorders and violence: what is the link?

Despite a well-documented association between personality disorders (PDs) and violence, the relationship between them is complicated by the high comorbidity of mental disorders, the heterogeneity of violence (particularly in regard to its motivation), and differing views regarding the way PDs are conceptualised and measured. In particular, it remains unclear whether there is a causal relationship between PDs and violence, and what the psychological mechanisms might be that mediate such a relationship. Here, a perspective on PD and violence is offered that views the relationship between them through the lenses of the Five Factor Model of personality and a quadripartite typology of violence. Evidence is reviewed suggesting that emotion dysregulation/impulsiveness, psychopathy, and delusional ideation conjointly contribute to the increased risk of violence shown by people with PD, and do so by contributing to a broad severity dimension of personality dysfunction. This view is consistent with the abandonment of personality disorder categories in the forthcoming eleventh edition of the International Classification of Diseases (ICD-11), where severity of personality disorder is defined in terms of the degree of harm to self and others.

Personality and genes: remarks from a biological perspective

Although there is no doubt that genes’ functions influence human personality, years of studies provided no clear picture on regulation of particular traits by specific genes. In this article, an overview of the complexity of the system of genetic control of personality is presented, and the level of complications of biological processes operating in this system is underlined. The methodology of studies devoted to determine effects of genes on personality traits is discussed, and limitations of various methods in such studies are indicated. Finally, suggestions for further research are listed and commented on. It is likely that to increase the level of our understanding of genetic mechanisms that modulate human personality, researchers conducting further studies will have to focus on using large sample sizes, performing independent replications, considering experiments on animal models, integrating cross-cultural data and epigenetic measures, and performing interdisciplinary experiments which combine methods of various disciplines, such as biology and psychology.