Effects of intranasal oxytocin on steroid hormones in men and women

The interplay of oxytocin and sex hormones

The neuropeptide oxytocin has historically been associated with reproduction and maternal behavior. However, more recent research has uncovered that oxytocin has a much wider range of roles in physiology and behavior. Despite the excitement surrounding potential therapeutical applications of intranasally administered oxytocin, the results of these intervention studies have been inconsistent. Various reasons for these mixed results have been proposed, which tend to focus on methodological issues, such as study design. While methodological issues are certainly important, emerging evidence suggests that the interaction between oxytocin and sex hormones may also account for these varied findings. To better understand the purpose and function of the interaction of oxytocin with sex hormones, with a focus on estrogens, progesterone, and testosterone, we conducted a comprehensive thematic review via four perspectives: evolutionary, developmental, mechanistic, and survival. Altogether, this synergistic approach highlights the critical function of sex hormone activity for accomplishing the diverse roles of oxytocin via the modulation of oxytocin release and oxytocin receptor activity, which is also likely to contribute to the heterogeneity of outcomes after oxytocin administration.

The impact of oxytocin on thiol/disulphide and malonyldialdehyde/glutathione homeostasis in stressed rats

We aimed to investigate the impact of oxytocin on serum thiol/disulphide and malonylyldialdehyde (MDA)/glutathione balance under acute stress (AS) and chronic stress (CS) exposure in rats. Animals were allocated into control (C), AS and CS groups, then the groups subdivided as intranasal oxytocin or saline applied groups, randomly. Animals in the AS or CS groups were exposed to combined cold-immobilisation stress. Salivary corticosterone levels and elevated plus maze (EPM) scores were used to assess stress response. MDA, glutathione, thiol-disulphide levels were measured in the serum samples. Oxytocin treatment attenuated stress response regardless of the stress duration verified by lower corticosterone level and favorable profile in EPM parameters measured. Furthermore, oxytocin modulated oxidant profile suggesting lowered oxidant stress with decreased serum MDA/glutathione and disulfide/native thiol ratios. Oxytocin improves the response of organism to stress via both its anxiolytic and antioxidant effects. That's why it can be considered as a protective measure to employ methods to increase endogenous oxytocin and/or to apply exogenous oxytocin to prevent stress-induced increase in oxidant stress, which plays a pivotal role in the pathogenesis of various stress-related diseases.

A Novel Role of CD38 and Oxytocin as Tandem Molecular Moderators of Human Social Behavior

Oxytocin is an important modulator of human affiliative behaviors, including social skills, human pair bonding, and friendship. CD38 will be discussed as an immune marker and then in more detail the mechanisms of CD38 on releasing brain oxytocin. Mention is made of the paralogue of oxytocin, vasopressin, that has often overlapping and complementary functions with oxytocin on social behavior. Curiously, vasopressin does not require CD38 to be released from the brain. This review discusses the social salience hypothesis of oxytocin action, a novel view of how this molecule influences much of human social behaviors often in contradictory ways. The oxytocinergic-vasopressinergic systems are crucial modulators of broad aspects of human personality. Of special interest are studies of these two hormones in trust related behavior observed using behavioral economic games. This review also covers the role of oxytocin in parenting and parental attachment. In conclusion, the effects of oxytocin on human behavior depend on the individual's social context and importantly as well, the individual's cultural milieu, viz. East and West. ACRONYMS: ACC = Anterior Cingulate ADP = Adenosine diphosphate AQ = Autism Quotient cADPR = Cyclic ADP-ribose CNS = Central nervous system DA = Dopamine eQTLC = Expression Quantitative Trait Loci LC-NE = Locus Coeruleus-Norepinephrine MRI = Magnetic Resonance Imaging OFC = Orbitofrontal cortices OXT = Oxytocin RAGE = Receptor for advanced glycation end-products SARM1 = Sterile Alpha and toll/interleukin-1 receptor motif-containing 1 TRPM2= Transient Receptor Potential Cation Channel Subfamily M Member 2 AVP = Vasopressin.

Can oxytocin inhibit stress-induced hyperalgesia?

Stress-induced hyperalgesia is a problematic condition that lacks an effective therapeutic measure, and hence impairs health-related quality of life. The regulation of stress by oxytocin (OT) has overlapping effects on pain. OT can alleviate pain directly mainly at the spinal level and the peripheral tissues. Additionally, OT plays an analgesic role by dealing with stress and fear learning. When OT relieves stress by targeting the prefrontal brain regions and the hypothalamic-pituitary-adrenal axis, the body's sensitivity to pain is attenuated. Meanwhile, OT facilitates fear learning and may, in turn, enhance the anticipatory actions to painful stimulation. The unique therapeutic value of OT in patients suffering from stress and stress-related hyperalgesia conditions is worth considering. We reviewed recent advances in animal and human studies involving the effects of OT on stress and pain, and discussed the possible targets of OT within the descending and ascending pathways in the central nervous system. This review provides an overview of the evidence on the role of OT in alleviating stress-induced hyperalgesia.

Associations between oxytocin and cortisol reactivity and recovery in response to psychological stress and sexual arousal

Previous research suggests a dynamic regulatory relationship between oxytocin and cortisol, but the specific nature of this relationship and its context-specificity have not been fully specified. In the present study, we repeatedly assessed both salivary oxytocin and salivary cortisol during two experimental sessions (one inducing sexual arousal and one inducing psychological stress), conducted two weeks apart with the same group of 63 female participants. Baseline cortisol and baseline oxytocin were significantly correlated in both sessions. Cortisol levels showed significantly different patterns of change during the stress assessment than during the sexual arousal assessment, but oxytocin showed similar patterns of change across both assessments. Greater cortisol stress reactivity predicted higher oxytocin levels immediately after the stressor, but a different pattern emerged during the arousal assessment: Greater oxytocin arousal reactivity predicted attenuated post-arousal reductions in cortisol. For both cortisol and oxytocin, individual differences in women's reactivity to sexual arousal did not predict their reactivity to psychological stress. These findings contribute new insights regarding associations between cortisol and oxytocin reactivity and recovery in different psychological contexts.

Oxytocin drives prosocial biases in favor of attractive people

Current perspectives on attractiveness-related prosocial biases emphasize the contribution of evolutionarily shaped mating drives. Here, we extend these concepts by highlighting the pivotal role of the hypothalamic peptide oxytocin in augmenting the salience and rewarding value of social stimuli, including the partner's face, thereby fostering social bonding in general and the stability of monogamous pair bonds and offspring care in particular.

The role of trauma in the hormonal interplay of cortisol, testosterone, and oxytocin in adolescent aggression

Although numerous studies have examined the neuroendocrinology of aggression, the findings are mixed and focused on cortisol and testosterone. We argue that past findings remain inconclusive partly because the key roles of oxytocin and trauma have not been systematically integrated yet. Oxytocin is associated with social behavior and interacts with cortisol and testosterone, whereas trauma is a crucial risk factor of aggression that strongly affects hormonal activity. In this review, we investigate the role of trauma in the hormonal interplay of cortisol, testosterone, and oxytocin in aggression during adolescence. We first discuss how these hormones interact with each other and how trauma influences these interactions and then we propose a model that highlights the role of trauma in the hormonal interplay in aggression. We suggest that the timing of trauma has a distinct effect on hormonal activity and it should be integrated into any comprehensive model. Current trauma is linked to different levels of oxytocin, cortisol, testosterone, and testosterone/cortisol ratio than childhood trauma, but this distinction is also influenced by gender and type of aggression. We conclude that in order to better understand the neuroendocrinology of aggression, it is crucial to incorporate the investigation of oxytocin and trauma in future research.

Oxytocin and Interpersonal Relationships

The neuropeptide oxytocin (OT) has emerged as a potent modulator of diverse aspects of interpersonal relationships. OT appears to work in close interaction with several other neurotransmitter networks, including the dopaminergic reward circuit, and to be dependent on sex-specific hormonal influences. In this chapter, we focus on four main domains of OT and interpersonal relationships, including (1) the protective effect of OT on an individual's ability to withstand stress (i.e., stress buffering), (2) the effect of OT on emotion recognition and empathy, (3) OT's ability to enhance social synchrony and cooperation among individuals, and (4) the effect of OT on an individual's perception of social touch. We then illustrate the connection between OT and loneliness while grieving the loss of a loved one. We finish by discussing the clinical potential of OT, focusing on its potential role as an adjunct to psychotherapy, its enhancement through sex-specific hormonal influences, and the difficulties that present themselves when considering OT as a therapy. Overall, we argue that OT continues to hold strong therapeutic promise, but that it is strongly dependent on internal and external influences, for instance the patient's personal past experiences and interaction with the therapist, in order to provide the best possible therapy.

Oxytocin and Anxiety Disorders: Translational and Therapeutic Aspects

PURPOSE OF REVIEW

This review aims to evaluate the most recent literature examining the oxytocin (OXT) system's role in human anxiety by surveying various fields of preclinical and clinical research supporting this role, and queries whether the OXT system might be a target for novel anxiolytics.

RECENT FINDINGS

Evidence from the diverse body of literature presented here, from translational research, genetic and neuroimaging studies, to clinical trials of intranasal (IN) OXT reveals a positive association. In addition, some moderators (e.g., sex, specificities to cues) of OXT's anxiolytic effects can have an important influence on its outcomes, awaiting further research. Evidence for the role of OXT in regulating anxiety is undeniable. We expect that the diverse particularities of the OXT system will help broaden our understanding of anxiety and stress-related disorders. We conclude that OXT promises an enticing treatment option for human anxiety disorders especially those associated with socio-emotional dysfunctions.

Hormonal systems, human social bonding, and affiliation

Which hormones are implicated in human social bonding and affiliation? And how does field research speak to this issue? We begin by laying out a broad view of how endocrine hormones in general modulate life history allocations of energy and other resources, and the ways in which their neuromodulatory functions must be understood within a broader conceptualization of how they have been shaped to affect allocations. We then turn to four specific hormones or hormone families that have received much attention: oxytocin, opioids, prolactin, and progesterone. Each plays a role in regulating psychological capacities and propensities that underlie individuals' interactions with important social targets. Yet in no case is it clear exactly what regulatory roles these hormones play. We suggest several directions for future research.

Oxytocin in the socioemotional brain: implications for psychiatric disorders

The neuropeptide oxytocin (OXT), highly conserved during evolution, is an important modulator of social and emotional processes across many species. During the last decade, a large body of literature has revealed its effects on different aspects of social behavior, including social stress and anxiety, social memory, affiliation and bonding, emotion recognition, mentalizing, empathy, and interpersonal trust. In addition, as impairments in these social domains can be observed in a number of neuropsychiatric disorders, such as autism, social anxiety disorder, depression, schizophrenia, and borderline personality disorder, the role of OXT in mental disorders and their treatment has been intensively studied. The present paper gives a short overview of these lines of research and shows how OXT has become a promising target for novel treatment approaches for mental disorders characterized by social impairments.

Effects of Intranasal Oxytocin on Emotion Regulation in Insecure Adolescents: Study Protocol for a Double-Blind, Randomized Controlled Trial

Background

Emotional dysregulation and impaired attachment are potential contributors to the development of psychopathology in adolescence. This raises the question of whether oxytocin (OT), the paradigmatic “attachment hormone,” may be beneficial in such contexts. Recent evidence suggests that intranasal administration of OT increases affiliative behavior, including trust and empathy. OT may also facilitate social reciprocity by attenuating the stress response to interpersonal conflict. To date, few studies have investigated the effects of intranasal oxytocin (IN-OT) on neurophysiological emotion regulation strategies in healthy adolescents, particularly during parent-adolescent interaction. To understand these mechanisms, our study will examine the effects of IN-OT on emotion regulation in adolescents during parent-adolescent stressful interactions, and on each adolescent’s visual and neurophysiological strategies when visualizing attachment-related pictures. We hypothesize that IN-OT will influence psychophysiological outcomes under conditions of stress. We predict that IN-OT will momentarily increase feelings of safety and attenuate stress and hostile behavior during conflict situations. OT may also enhance attachment security by increasing comfort and proximity-seeking, and reducing neurophysiological hyperactivation.

Objective

The objective of this study is to evaluate the effects of IN-OT on insecure adolescents by studying their behavior and discourse during a disagreement with one of their parents. Their neurophysiological responses to pictures eliciting attachment-related emotions and their visual exploration strategies will also be investigated.

Methods

In this randomized, double-blind, placebo-controlled parallel-group design, 60 healthy male adolescents classified as insecurely attached will receive 24 international units (IU) of IN-OT versus placebo (PB), 45 minutes before the experimental tasks. Each adolescent will then be invited to engage in an experimental conflict discussion with one of his parents. The conflict session will be videotaped and coded for verbal and non-verbal interaction behavior, using the Goal-Corrected Partnership in Adolescence Coding System (GPACS). Each adolescent will then be asked to visualize attachment-related pictures on a screen. Eye-tracking (ET) and neurophysiological responses, including electrodermal activity (EDA) and heart rate (HR), will be recorded simultaneously and continuously during attachment-related picture viewing (Besançon Affective Picture Set-Adolescents, BAPS-Ado).

Results

Enrollment for the study was completed in May 2016. Data analysis commenced in July 2016. Study results will be submitted for publication in the winter of 2017.

Conclusions

OT is a complex molecule with many facets that are not yet fully understood. This experimental protocol will increase scientific and clinical knowledge of emotion regulation skills in insecure adolescents by assessing the impact of IN-OT on parent-adolescent interaction and on the visual processing of attachment-related emotions. Positive results could lead to therapeutic uses of IN-OT to treat emotion dysregulation in adolescence.

Parent observed neuro-behavioral and pro-social improvements with oxytocin following surgical resection of craniopharyngioma

Social and emotional impairment, school dysfunction, and neurobehavioral impairment are highly prevalent in survivors of childhood craniopharyngioma and negatively affect quality of life. As surgical resection of craniopharyngioma typically impairs hypothalamic/pituitary function, it has been postulated that perhaps post-operative deficiency of the hormone oxytocin may be the etiology of social/emotional impairment. Research on the benefits of oxytocin treatment as a hormone facilitating social interaction is well established. However, no research has yet been conducted on patients with known pituitary/hypothalamic dysfunction due to structural lesions or surgery. This case report investigates the effects of oxytocin therapy on a youngster with pituitary/hypothalamic dysfunction after craniopharyngioma removal. In this individual, treatment with low dose intranasal oxytocin resulted in increased desire for socialization and improvement in affection towards family. In light of these findings, the authors believe that further research into the potential benefits of intranasal oxytocin therapy for patients with panhypopituitarism is necessary to determine whether a broader population may also benefit from intranasal oxytocin therapy.

Evolving the neuroendocrine physiology of human and primate cooperation and collective action

While many hormones play vital roles in facilitating or reinforcing cooperative behaviour, the neurohormones underlying competitive and cooperative behaviours are largely conserved across all mammals. This raises the question of how endocrine mechanisms have been shaped by selection to produce different levels of cooperation in different species. Multiple components of endocrine physiology--from baseline hormone concentrations, to binding proteins, to the receptor sensitivity and specificity--can evolve independently and be impacted by current socio-ecological conditions or individual status, thus potentially generating a wide range of variation within and between species. Here, we highlight several neurohormones and variation in hormone receptor genes associated with cooperation, focusing on the role of oxytocin and testosterone in contexts ranging from parenting and pair-bonding to reciprocity and territorial defence. While the studies reviewed herein describe the current state of the literature with regard to hormonal modulators of cooperation and collective action, there is still a paucity of research on hormonal mechanisms that help facilitate large-scale collective action. We end by discussing several potential areas for future research.