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Exposure to stress in early life can have a significant impact on individuals. However, the effects of early-life stress (ELS) on prosocial behavior remain unclear, as do the underlying mechanisms. In this study, ICR juvenile mice were subjected to juvenile chronic social defeat stress (jCSDS) between postnatal days 32 and 41, during which body weight changes were continuously monitored. The behaviors of adult mice were evaluated using the open field test (OFT), the social interaction test (SIT), and the prosocial choice task (PCT). ELISA was used to quantify serum levels of oxytocin, serotonin, and dopamine. The density of dendritic spines in the basolateral amygdala was evaluated by Golgi staining. Behavioral test results showed that jCSDS induced anxiety-like behavior and decreased prosocial selection tendency in mice. Additionally, exposure to jCSDS increased the serum levels of oxytocin, decreased those of serotonin, and increased the density of dendritic spines in the basolateral amygdala. Correlation analysis indicated that prosocial behavior was negatively correlated with serum oxytocin levels and dendritic spine density in the basolateral amygdala. These results suggested that jCSDS reduced prosocial behavior, possibly due to changes in serum oxytocin contents and adaptive changes in amygdaloid neurons., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: Obesity is a complex heterogeneous disease often associated with dysfunctional eating behavior patterns. Oxytocin (OT) is a neurohormone involved in the regulation of energy metabolism and eating behavior. The aim of the present study was to evaluate in a population of patients with obesity circulating levels of OT and dysfunctional eating behaviors in relation to anthropometric, hormonal and metabolic parameters., Methods: A prospective, observational, single-center study was conducted at the Center of High Specialization for the Care of Obesity of Sapienza University of Rome. Adult subjects with body mass index (BMI) ≥ 30 kg/m2 were recruited. Body impedance assessment (BIA), biochemical and hormonal parameters, plasma OT concentration analysis and the Eating Behaviors Assessment for Obesity (EBA-O) questionnaire were evaluated., Results: A total of 21 patients, 16 females and 5 males, with a mean age of 45.7 ± 15.1 years, mean BMI of 40.89 ± 8.02 kg/m 2 and plasma OT concentration of 1365.61 ± 438.03 pg/mL were recruited. The dysfunctional eating behavior traits investigated by the EBA-O appear significantly associated with metabolic derangements. In particular, night eating is associated with alterations in lipid metabolism (p < 0.01). Circulating OT correlates positively with BMI (r = 0,43; p < 0.05), and Hepatic Steatosis Index (HIS) (r = 0.46; p < 0.05), while its role in subjects with obesity and alterations in glucose metabolism is less clear. Interestingly, circulating OT levels < 1312.55 pg/mL may be predictive of food addiction (100% sensitivity; 62.5% specificity)., Conclusions: Despite the need for larger studies to confirm their validity, the clinical utility of the EBA-O and circulating OT in identifying dysfunctional eating behaviors appears promising., Competing Interests: Declarations. Ethics approval: The study was carried out in accordance with the code of ethics of the World Medical Association for human studies (Declaration of Helsinki, 2001) and Good Clinical Practice (GCP). The research protocol (“SUMOTO”) was approved by the Ethical Committee of Sapienza University of Rome (rif. 5475). All patients were informed about the possible risks and benefits of the proposed interventions and signed an informed consent form to voluntarily participate in this study. Competing interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential Competing interests., (© 2025. The Author(s).)

Context: Neurohypophysis (NH) function in eating disorders (ED) remains poorly elucidated. Studies on vasopressin and oxytocin display inconclusive findings regarding their levels and associations with psychological complications in ED. The profile of opioid tone, a crucial NH activity regulator, is also unknown., Objective: To characterise the circadian profile of NH hormones and NH opioid tone using positron emission tomography/MRI (PET/MRI) imaging in patients with ED compared to healthy controls., Methods: Twelve-point plasma circadian profiles of copeptin and oxytocin, alongside nutritional and psychological scores, were assessed in age-matched female participants: 13 patients with anorexia nervosa restrictive-type (ANR), 12 patients recovered from AN (ANrec), 14 patients with bulimia nervosa and 12 controls. Neurohypophysis PET/MRI [ 11 C] diprenorphin binding potential (BP ND ) was evaluated in AN, ANrec and controls., Results: Results revealed lower copeptin circadian levels in both ANR and ANrec compared to controls, with no oxytocin differences. Bulimia nervosa exhibited elevated copeptin and low oxytocin levels. [ 11 C] diprenorphin pituitary binding was fully localised in NH. Anorexia nervosa restrictive-type displayed lower NH [ 11 C] diprenorphin BP ND (indicating higher opioid tone) and volume than controls. In ANR, copeptin inversely correlated with osmolarity. Neurohypophysis [ 11 C] diprenorphin BP ND did not correlated with copeptin or oxytocin., Conclusion: Copeptin demonstrated significant group differences, highlighting its potential diagnostic and prognostic value. Oxytocin levels exhibited conflicting results, questioning the reliability of peripheral blood assessment. Increased NH opioid tone in anorexia nervosa may influence the vasopressin or oxytocin release, suggesting potential therapeutic applications., (© 2024 The Author(s). European Eating Disorders Review published by Eating Disorders Association and John Wiley & Sons Ltd.)

Pregnancy is accompanied by hormonal fluctuation, including increased cortisol and oxytocin (OT). Although the implications of these hormones during pregnancy are extensively studied, their normative variability is not well established. Therefore, we evaluated how serum cortisol and OT levels behave throughout pregnancy. This longitudinal study is part of a population-based cohort of pregnant women living in a city in Southern Brazil. Pregnant women up to 24 gestational weeks were evaluated at the time of identification (1st wave, N=983) and 60 days after the initial interview (2nd wave, N=840). At both times, blood samples were collected for hormonal dosage. We investigated the trajectory of these hormones throughout pregnancy using growth curve modeling. The best-fitting model was the exponential growth model, in which the variance explains approximately 79.1 % of the outcome. Thus, the cortisol level was, on average, at 44.2 μg/dl (95 %CI: 29.2;59.1, p<0.001) in the first gestational week, with an increase of approximately 2.0 % (95 %CI: 1.01;1.02, p<0.001) each week. OT showed no significant changes. While cortisol appears to follow a trajectory of exponential increase, possibly in response to the demands of fetal development, the variation in OT levels throughout pregnancy still remains constant subject to further investigation., Competing Interests: Declaration of Competing Interest Conflict of interest On behalf of all authors, the corresponding author states that no conflicts of interest exist., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Pain is a major non-motor symptom of Parkinson's disease (PD). The relationship between hyperalgesia and neuropeptides originating from paraventricular nucleus (PVN) in 6-hydroxydopamine (6-OHDA) rats has already been investigated for oxytocin (OXT), but not yet for arginine vasopressin (AVP) and corticotropin-releasing hormone (CRH). The present study aimed to investigate the alterations in these neuropeptides following nociceptive stimulation in PD model rats and to examine the mechanisms of hyperalgesia. Dopaminergic nigrostriatal lesions were induced by injecting 6-OHDA into the medial forebrain bundle. Subcutaneous formalin injection into the vibrissa pad was performed in rats as a nociceptive stimulus in the orofacial region. Dopamine depletion's effect on nociception was assessed by counting the p-ERK-immunoreactive (-IR) cells in the trigeminal spinal subnucleus caudalis (Vc). The PD model rats induced by 6-OHDA injection (6-OHDA rats) showed a significantly higher number of p-ERK-IR cells in the Vc than the sham rats, confirming hyperalgesia in 6-OHDA rats. Then, we investigated the immunohistochemical responses to OXT, AVP, and CRH cells in the PVN and examined the changes in blood levels of these neuropeptides. As a result, formalin injection increased neuronal activity and blood levels of OXT and CRH in sham rats, but these were suppressed in the 6-OHDA rats. Contrarily, neuronal activity and blood level of AVP were unaffected by nociceptive stimuli and were significantly lower in 6-OHDA rats than in sham rats. Our findings suggest that OXT and CRH suppression is linked to hyperalgesia in PD, whereas AVP does not directly influence the observed hyperalgesia., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The purpose of this study was to examine whether there are sex differences in vasomotor responses and receptor localization of hormones and neuropeptides with relevance to migraine (vasopressin, oxytocin, estrogen, progesterone, testosterone, amylin, adrenomedullin and calcitonin gene-related peptide (CGRP)) in human intracranial arteries., Methods: Human cortical cerebral and middle meningeal arteries were used in this study. The tissues were removed in conjunction with neurosurgery and donated with consent. Vasomotor responses of arteries, after exposure to hormones or neuropeptides, were recorded using a wire myograph. Immunohistochemistry was performed to examine the expression and localization of their receptors within human intracranial arteries., Results: Vasopressin showed the strongest contractile responses, followed by oxytocin and progesterone. CGRP displayed the strongest vasodilatory response when compared to adrenomedullin, amylin, testosterone and estrogen. No significant differences were observed in vasomotor responses between male and female arteries. The vasomotor effects were supported by the presence of corresponding receptors in the vascular smooth muscle cells. Estrogen receptors (ERα and ERβ), progesterone receptor (PR), vasopressin 1a receptor (V1aR), and the oxytocin receptor (OTR) were expressed in the walls of both cerebral arteries overlying the cerebral cortex and intracranial arteries of the dura mater. ERα, V1aR, and PR were found to be localized in both smooth muscle cells and endothelium, whereas OTR was exclusively located within the smooth muscle cells., Conclusions: Hypothalamic, sex hormones and the pancreas hormone (amylin) receptors are expressed in the human intracranial artery walls. The vasomotor responses revealed no sex differences, however contractile responses to vasopressin was higher and more potent in MMA compared to CCA when pooling data from both sexes. Overall, the hormones estrogen, progesterone and oxytocin, which drop in circulating levels at onset of menstruation, only showed modest vasomotor responses as compared to CGRP. This suggests that their role in inducing menstrual migraine attacks is not directly related to vasomotor responses., Competing Interests: Declarations. Ethics approval and consent to participate: Human samples were acquired, with oral and written consent, from patients undergoing neurosurgery at the University Hospital of Lund. The Human Ethics board approved the study design. Consent for publication: All authors have read and consented to the manuscript for publication. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

The co-evolution of social behavior and the immune system plays a critical role in individuals' adaptation to their environment. However, also need for further research on the key molecules that co-regulate social behavior and immunity. This study focused on neonatal mice that were separated from their mothers for 4 hours per day between the 6th and 16th day after birth. The results showed that these mice had lower plasma levels of IFN-γ and oxytocin, but higher levels of plasma glucocorticoids (GC), then impacting their social abilities. Additionally, maternal separation led to decreased levels of BDNF, IGF2, and CREB mRNAs in the hippocampus, while levels in the prefrontal cortex (PFC) remained unaffected. Maternal separation also resulted in increased levels of oxytocin and CRH mRNA in the hypothalamus, as well as an increase in CD45 + lymphocyte subsets in the meninges and choroid plexus (CP), with CD8 + lymphocytes in meninges and CD4 + lymphocytes in CP showing an increase. In IFN-γ -/- mice, a decrease in social preference was observed alongside lower plasma oxytocin levels. Moreover, IFN-γ -/- mice exhibited reduced numbers of oxytocin neurons in the paraventricular nucleus of the paraventricular nucleus of hypothalamus (PVN), decreased BDNF levels in the PFC and hippocampus, and alterations in CD45 + lymphocytes in CP and meninges, with an increase in CD8 + lymphocytes in meninges and CD4 + lymphocytes in CP. These findings highlight the immunological impact of social stress on IFN-γ regulation, suggesting that the immunomodulatory molecule IFN-γ may influence social behavior by affecting synaptic efficiency in brain regions such as the hippocampus and PFC, which are linked to oxytocin in the PVN., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Both social support and social stress can impact adolescent physiology including hormonal responses during the sensitive transition to adolescence. Social support from parents continues to play an important role in socioemotional development during adolescence. Sources of social support and stress may be particularly impactful for adolescents with social anxiety symptoms. The goal of the current study was to examine whether adolescent social anxiety symptoms and maternal comfort moderated adolescents' hormonal response to social stress and support. We evaluated 47 emotionally healthy 11- to 14-year-old adolescents' cortisol and oxytocin reactivity to social stress and support using a modified version of the Trier Social Stress Test for Adolescents that included a maternal comfort paradigm. Findings demonstrated that adolescents showed significant increases in cortisol and significant decreases in oxytocin following the social stress task. Subsequently, we found that adolescents showed significant decreases in cortisol and increases in oxytocin following the maternal comfort paradigm. Adolescents with greater social anxiety symptoms showed higher levels of cortisol at baseline but greater declines in cortisol response following maternal social support. Social anxiety symptoms were unrelated to oxytocin response to social stress or support. Our findings provide further evidence that mothers play a key role in adolescent regulation of physiological response, particularly if the stressor is consistent with adolescents' anxiety. More specifically, our findings suggest that adolescents with higher social anxiety symptoms show greater sensitivity to maternal social support following social stressors. Encouraging parents to continue to serve as a supportive presence during adolescent distress may be helpful for promoting stress recovery during the vulnerable transition to adolescence., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Emotional management, combined with oxytocin massage and breast care, offers a comprehensive approach to boost prolactin release, enhance milk production, and improve breastfeeding outcomes. The aim of this study was to evaluate the effectiveness of combining emotional management with oxytocin massage and breast care in increasing oxytocin and prolactin hormone levels to address oligogalactia in working postpartum mothers. A quasi-experimental study was conducted at Kudus Community Health Center, Kudus Regency, Central Java, Indonesia, from January to March 2024. A total of 93 postpartum mothers were randomly assigned to three groups: (1) emotional management with oxytocin massage; (2) emotional management with breast care; and (3) lactation education only. Blood samples were collected before and after the interventions to measure oxytocin and prolactin levels. The present study found that emotional management combined with oxytocin massage significantly increased oxytocin levels from 505.0±264.0 pg/mL to 600.0±231.3 pg/mL (mean difference: 103 pg/mL; p =0.002) and prolactin levels from 191.0±67.3 ng/mL to 233.0±86.8 ng/mL (mean difference: 27 ng/mL; p =0.001). The emotional management and breast care group showed a smaller increase in oxytocin (362.0±175.1 pg/mL to 418.0±185.1 pg/mL; mean difference: 23 pg/mL; p =0.048) and a significant increase in prolactin (195.0±48.8 ng/mL to 255.0±82.3 ng/mL; mean difference: 38 ng/mL; p =0.049). In contrast, the lactation education group showed no significant changes in oxytocin ( p =0.756) or prolactin levels ( p =0.341). In conclusion, emotional management combined with oxytocin massage significantly increased both oxytocin and prolactin levels, suggesting that integrating emotional management and oxytocin massage may be an effective strategy for postpartum lactation support., Competing Interests: All the authors declare that there are no conflicts of interest, (© 2024 The Author(s).)

Racemic 3,4-methylenedioxymethamphetamine (MDMA) acutely increases mood, feelings of empathy, trust, and closeness to others and is investigated to assist psychotherapy. Preclinical research indicates that S-MDMA releases monoamines and oxytocin more potently than R-MDMA, whereas R-MDMA more potently stimulates serotonin 5-hydroxytryptamine-2A receptors. S-MDMA may have more stimulant properties, and R-MDMA may be more psychedelic-like. However, acute effects of S- and R-MDMA have not been examined in a controlled human study. We used a double-blind, randomized, placebo-controlled, crossover design to compare acute effects of MDMA (125 mg), S-MDMA (125 mg), R-MDMA (125 mg and 250 mg), and placebo in 24 healthy participants. Outcome measures included subjective, autonomic, and adverse effects, pharmacokinetics, and plasma oxytocin, prolactin, and cortisol concentrations. S-MDMA (125 mg) induced greater subjective effects ("stimulation," "drug high," "happy," "open") and higher increases in blood pressure than R-MDMA (both 125 and 250 mg) and MDMA (125 mg). Unexpectedly, R-MDMA did not produce more psychedelic-like effects than S-MDMA. S-MDMA increased plasma prolactin more than MDMA, and S-MDMA increased plasma cortisol and oxytocin more than MDMA and R-MDMA. The plasma elimination half-life of S-MDMA was 4.1 h after administration. The half-life of R-MDMA was 12 and 14 h after the administration of 125 and 250 mg, respectively. Half-lives for S-MDMA and R-MDMA were 5.1 h and 11 h, respectively, after racemic MDMA administration. Concentrations of the CYP2D6-formed MDMA-metabolite 4-hydroxy-3-methoxymethamphetamine were lower after R-MDMA administration compared with S-MDMA administration. The pharmacokinetic findings are consistent with the R-MDMA-mediated inhibition of CYP2D6. Stronger stimulant-like effects of S-MDMA in the present study may reflect the higher potency of S-MDMA rather than qualitative differences between S-MDMA and R-MDMA. Equivalent acute effects of S-MDMA, MDMA, and R-MDMA can be expected at doses of 100, 125, and 300 mg, respectively, and need to be investigated.Trial registration: ClinicalTrials.gov identifier: NCT05277636., Competing Interests: Competing interests: MEL is a consultant for Mind Medicine, Inc. The other authors declare no conflicts of interest. Knowhow and data associated with this work are owned by the University Hospital Basel and were licensed by Mind Medicine, Inc. Mind Medicine, Inc., had no role in planning or conducting the present study or writing the publication., (© 2024. The Author(s).)

Introduction: Despite emerging evidence on oxytocin's role in eating disorders,there is a need for a comprehensive review to integrate findings across neurobiological, genetic, hormonal, and therapeutic dimensions. This scoping review synthesizes existing literature on OXT's role in EDs and proposes a new theoretical perspective based on diverse research findings., Methods: In accordance with PRISMA guidelines, we systematically synthesized all peer-reviewed articles indexed on PubMed which focused on both OXT and EDs as of December 2023 (k = 32 studies, n = 1942 participants). After summarizing this literature in tables, we completed the narrative synthesis with a discussion of mechanisms informed by an unstructured literature review., Results: The existing studies propose a connection between OXT receptor Oxtr polymorphisms and ED diagnoses, severity of symptoms, macronutrient preferences, reward function, and early life stress. In addition, OXT plasma levels normalized with ED symptom reduction. Although some OXT studies have failed to show therapeutic changes in food intake and weight, few have reported ameliorations in brain function, food-related attentional bias, cognition, and emotional regulation. Some data have also suggested a contributory role of the transforming growth factor β (TGFβ) and sterol regulatory element binding proteins (SREBPs) to the etiology of EDs through Oxtr expression., Conclusion: Although the current evidence does not support OXT as a standalone cause of or treatment for EDs, OXT research holds promise as a way of identifying future therapies, and OXT itself may serve as a valuable adjunct., Competing Interests: Declaration of competing interest All authors declare no competing interests or funding sources., (Copyright © 2024. Published by Elsevier Inc.)

In group-living animals, chronic juvenile social isolation stress (SIS) can profoundly affect behavior and neuroendocrine regulation. However, its impact on social behavior in avian species, particularly regarding sex-specific neural circuit differences, remains underexplored. This study focused on zebra finches, a species known for its social clustering and cognitive abilities, to elucidate these influences. Results indicated that SIS significantly increased plasma corticosterone levels in females but not in males, suggesting a heightened stress response and susceptibility in females. Additionally, SIS disrupted sociality and flocking behavior in both sexes, with more severe impairments in social recognition observed in females. Mesotocin (MT) levels in the lateral septum of both sexes and in the ventromedial hypothalamus of females were found to mediate the SIS effect, while vasotocin (VT) levels within the social behavior network remained unchanged. Pharmacological interventions confirmed the critical role of MT in reversing SIS-induced impairments in sociality, flocking behavior, and social recognition, particularly in females. These findings highlight unique nucleus- and sex-dependent variations in MT and VT regulation, providing novel insights into the mechanisms governing avian social behavior. This study advances our understanding of the independent evolutionary pathways of neural circuits and neuroendocrine systems that modulate social behaviors across different taxonomic groups.

Background: Clowning has been used in many hospitals, particularly for children. Studies suggest the effectiveness of this methodology, but more evidence is needed. The aim of this study was to evaluate the impact of a humour therapy intervention on biological markers, pain and anxiety levels in paediatric patients., Methods: Three different clinical contexts were chosen to assess the effect of clowning interventions: patients who were subjected to venepuncture (group 1), patients undergoing general anesthesia for any cause (group 2)and patients hospitalized in the pediatric ward without distinction of their disease (group 3). Groups 1 and 2 were divided into control (C) and intervention (I) subgroups. A saliva sample was taken from all the children to measure oxytocin and cortisol levels by ELISAs. Validated scales and crying time were used to determine pain, stress, and anxiety levels. Children in group 3 were assessed before and after the intervention, employing the same methods., Results: A total of 272 patients were included. The children in group 1 (n = 125) were 7.7 ± 3.2 years old, and 53.6% were females. 48% were in the I group, which showed decreased cortisol levels and increased oxytocin levels. The I group exhibited a decrease in perceived pain and crying time. The children in group 2 (n = 69) were aged 7.1 ± 3.5 years, and 36% were females. 51% were in the I group, which showed increased oxytocin levels and decreased cortisol levels, acute stress levels, perceived pain, and crying time. The children in group 3 (n = 78) were 8.6 ± 3.3 years old, and 54% of the children were females. There was an increase in oxytocin levels and a decrease in cortisol levels, stress levels and perceived pain following the intervention., Conclusions: This study suggested that an intervention based on clowning is an effective strategy for decreasing pain, stress, and anxiety levels in paediatric patients in different clinical contexts. These findings support the implementation of humour therapy programs in paediatric units., Competing Interests: Declarations Ethics approval and consent to participate This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of Universidad Tecnológica de Pereira (Code 32–160421). Written informed consent was obtained from the parents or proxies. Consent for publication Not applicable. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Importance: 3,4-Methylenedioxymethamphetamine (MDMA, or ecstasy) is a recreational drug being investigated for the treatment of posttraumatic stress disorder. Acute hyponatremia is a potentially serious complication after even a single dose of MDMA. The assumed etiology has been a vasopressin release inducing the syndrome of inappropriate antidiuresis combined with increased thirst, causing polydipsia and water intoxication., Objective: To investigate the incidence and severity of hyponatremia after a single dose of MDMA, underlying neuroendocrine mechanisms of action, and the potential effect of fluid restriction on lowering the incidence of hyponatremia., Design, Setting, and Participants: This ad hoc secondary analysis pooled data from 4 placebo-controlled crossover randomized clinical trials conducted at the University Hospital Basel, Basel, Switzerland. The 96 participants received experimental doses of MDMA between March 1, 2017, and August 31, 2022., Intervention: A single oral 100- or 125-mg dose of MDMA. Fluid intake was not restricted in 81 participants; it was restricted in 15., Main Outcomes and Measures: Plasma oxytocin, copeptin (marker of vasopressin), and sodium levels were measured repeatedly within 360 minutes after MDMA intake. The association of plasma oxytocin or copeptin levels with plasma sodium level at 180 minutes (peak concentration of MDMA) was determined., Results: Among the 96 participants, the mean (SD) age was 29 (7) years, and 62 (65%) were men. A total of 39 participants (41%) received a 100-mg dose of MDMA, and 57 (59%) received a 125-mg dose. At baseline, the mean (SD) plasma sodium level was 140 (3) mEq/L and decreased in response to MDMA by 3 (3) mEq/L. Hyponatremia occurred in 30 participants (31%) with a mean (SD) sodium level of 133 (2) mEq/L. In 15 participants with restricted fluid intake, no hyponatremia occurred, while in the 81 participants with unrestricted fluid intake, hyponatremia occurred in 30 (37%) (P = .002) with a difference in plasma sodium of 4 (95% CI, 2-5) mEq/L (P < .001) between both groups, suggesting that fluid restriction may mitigate the risk of hyponatremia. At baseline, the mean (SD) plasma oxytocin level was 87 (45) pg/mL and increased in response to MDMA by 388 (297) pg/mL (ie, a mean [SD] 433% [431%] increase at 180 minutes), while the mean (SD) copeptin level was 4.9 (3.8) pmol/L and slightly decreased, by 0.8 (3.0) pmol/L. Change in plasma sodium level from baseline to 180 minutes demonstrated a negative correlation with the changes in oxytocin (R = -0.4; P < .001) and MDMA (R = -0.4; P < .001) levels while showing no correlation with the change in copeptin level., Conclusions and Relevance: In this secondary analysis of 4 randomized clinical trials, a high incidence of acute hyponatremia was observed in response to MDMA, which may be mitigated by fluid restriction. Hyponatremia was associated with acute oxytocin but not copeptin release. This challenges the current hypothesis of direct vasopressin release and rather indicates that oxytocin mimics the effect of vasopressin in the kidneys due to structural homology.

This study aimed to increase our understanding of cardiac activity abnormalities in Prader-Willi Syndrome (PWS) and the relationship between cardiac activity, PWS behaviours thought to be associated with cardiac vagal tone and endogenous oxytocin and vasopressin levels. We compared cardiac activity (respiratory sinus arrhythmia (RSA), low-frequency heart rate variability (LF-HRV), heart period) in 30 adolescents and adults with PWS to 30 typically developing age-matched controls. RSA, LF-HRV, and heart period were lower in individuals with PWS than in the control group. In the control group, RSA was higher for females than males. However, for those with PWS, there was no difference between the sexes. Individuals with the mUPD genetic subtype had lower RSA and LF-HRV than participants with the PWS deletion subtype and compared to typically developing controls, no difference was found between the latter two groups. Heart period was also lower for those with mUPD compared to controls. Higher RSA reduced the odds of having temper outbursts and skin-picking. RSA was lower in those with PWS and psychosis compared to those with PWS without psychosis. Finally, we found RSA correlated with vasopressin for those with mUPD but not deletion. There was no relationship between RSA and oxytocin plasma or saliva levels. Our findings suggest autonomic dysfunction in PWS that is more marked in mUPD than deletion and potentially due to greater loss of parasympathetic activity in mUPD., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Thiacloprid (TCL), commonly known as Biscaya, is among the most widely used pesticides in agriculture, designed to eliminate insects by targeting their nicotinic receptors. This study explores the effects of orally administering TCL (at a dose of 50 mg/kg) on the hormone secretion crucial for pregnancy and the factors influencing abortion throughout the early, middle, and late stages of pregnancy in female rats. Following TCL exposure, there were significant increases in levels of 17β-Estradiol, prostaglandins F 2α and E 2 , and serum oxytocin hormone in different stages of pregnancy. In contrast, progesterone and endothelin-1 serum levels notably decreased during the initial and final stages of pregnancy. Additionally, TCL led to a substantial rise in lipid peroxidation levels and a decrease in total thiol molecules and total antioxidant capacity, especially in uterine tissue. Although TCL did not significantly affect the morphological characteristics of the delivered fetuses, it notably increased the number of abortions, especially during the second and third stages of pregnancy. In summary, our findings suggest that TCL elevates the risk of abortion in pregnant rats by disrupting the secretion of hormones crucial for fertility (such as 17β-Estradiol/progesterone) and by increasing the secretion of abortion-inducing hormones like prostaglandins and oxytocin. Furthermore, these effects may be associated with disruptions in the oxidant/antioxidant balance within the ovaries and uterus., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2024. Published by Elsevier Inc.)

Purpose: We recently demonstrated an additional oxytocin (OT) deficiency in patients with arginine vasopressin (AVP) deficiency (central diabetes insipidus) by using 3,4-methylenedioxy-methamphetamine (MDMA) as a novel provocation test. However, the implication of the MDMA provocation test in clinical practice might be challenging. Glucagon effectively stimulates vasopressinergic neurons with a strong increase in plasma copeptin. We therefore hypothesized that this provocation test might also stimulate OT., Methods: This is a predefined secondary analysis of a prospective double-blind, randomised, placebo-controlled cross-over trial involving ten patients with AVP deficiency and ten sex- and body-mass index-matched healthy participants at the University Hospital Basel, Switzerland. Each participant underwent the glucagon test (s.c. injection of 1 mg glucagon) and placebo test (s.c. injection of 0.9% normal saline). Plasma OT levels were measured at baseline, 60, 120 and 180 min after injection. The primary objective was to determine whether glucagon stimulates OT and whether OT levels differ between patients with AVP deficiency and healthy participants. The primary outcome (maximum change in OT within 180 min) was compared between groups and conditions using a linear mixed effects model., Results: In healthy participants, the median OT at baseline was 82.7 pg/ml [62.3-94.3] and slightly increased to a maximum of 93.3 pg/ml [87.2-121.1] after injection of glucagon, resulting in a change increase of 24.9 pg/ml [5.1-27.8]. Similarly, in patients with AVP deficiency, the median OT at baseline was 73.9 pg/ml [65.3-81.6] and slightly increased after glucagon injection to 114.9 pg/ml [70.9-140.9], resulting in a change increase of 36.8 pg/ml [-2.2 to 51.2]. The results from the mixed model showed no effect between glucagon compared to placebo on OT (difference: -0.5 pg/ml; 95%-CI [-25, 24]; p = 0.97) and no significant treatment-by-group interaction effect between patients compared to healthy participants (interaction: 28 pg/ml; 95%-CI [-7, 62]; p = 0.13)., Conclusion: We found no effect of glucagon on plasma OT levels and no difference between patients with AVP deficiency and healthy participants., (© 2024. The Author(s).)

The development of fetal organs can be impacted by systemic changes in maternal circulation, with the placenta playing a pivotal role in maintaining pregnancy homeostasis and nutrient exchange. In clinical obstetrics, oxytocin (OXT) is commonly used to induce labor. To explore the potential role of OXT in the placental homeostasis of OXT, we compared OXT levels in neonatal cord blood among neonates (23-42 weeks gestation) whose mothers either received prenatal OXT or experienced spontaneous labor. Our previous research revealed that the oxytocin receptor (OXTR), essential in forming the blood-retina barrier, is expressed in the retinal pigment epithelium (RPE). We hypothesized that perinatal OXT administration might influence the development of the neural retina and its vasculature, offering therapeutic potential for retinal diseases such as retinopathy of prematurity (ROP). Plasma OXT levels were measured using a commercial OXT ELISA kit. Human fetal RPE (hfRPE) cells treated with OXT (10 µM) were assessed for gene expression via RNA sequencing, revealing 14 downregulated and 32 upregulated genes. To validate these differentially expressed genes (DEGs), hfRPE cells were exposed to OXT (0.01, 0.1, 1, or 10 µM) for 12 h, followed by RNA analysis via real-time PCR. Functional, enrichment, and network analyses (Gene Ontology term, FunRich, Cytoscape) were performed to predict the affected pathways. This translational study suggests that OXT likely crosses the placenta, altering fetal OXT concentrations. RNA sequencing identified 46 DEGs involved in vital metabolic and signaling pathways and critical cellular components. Our results indicate that the perinatal administration of OXT may affect neural retina and retinal vessel development, making OXT a potential therapeutic option for developmental eye diseases, including ROP.

Aim: To assess oxytocin's acute glucoregulatory impact in men with type 2 diabetes in the context of our previous findings that oxytocin improves β-cell responsivity in healthy men., Methods: In a double-blind, crossover comparison, intranasal oxytocin (24 IU) and placebo, respectively, were administered to 25 fasted men with non-insulin-treated type 2 diabetes (age ± standard error of the mean, 63.40 ± 1.36 years; body mass index, 27.77 ± 0.66 kg/m 2 ; HbA1c, 6.86% ± 0.08%; Homeostatic Model Assessment of Insulin Resistance (HOMA-IR, 3.44 ± 0.39) 60 minutes before an oral glucose tolerance test (oGTT). Key outcomes were compared with previous results in men with normal weight or obesity., Results: Oxytocin compared with placebo increased plasma oxytocin concentrations and reduced the heart rate, but did not alter glucose metabolism in the 3 hours after oGTT onset (area under the curve, glucose, 2240 ± 80.5 vs. 2190 ± 69.5 mmol/L × min; insulin, 45 663 ± 4538 vs. 44 343 ± 4269 pmol/L × min; C-peptide, 235 ± 5.1 vs. 231 ± 15.9 nmol/L × min)., Conclusions: This outcome contrasts with the oxytocin-induced attenuation of early postprandial glucose excursions in normal-weight individuals, but is in line with the absence of respective effects in men with obesity. We conclude that insulin resistance in type 2 diabetes is associated with decreased sensitivity to the acute glucoregulatory effect of oxytocin in male individuals., (© 2024 The Author(s). Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.)

Aims: Postpartum haemorrhage (PPH) is the leading cause of maternal mortality worldwide. To prevent PPH, the WHO recommends administration of oxytocin (OT) immediately after birth, i.e. during the third stage of labour (TSL). Previous studies demonstrate that methods to quantify OT in biological matrices, e.g. enzyme-linked immunosorbent assays (ELISA), radioimmunoassays (RIA) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) lack the specificity and/or sensitivity to accurately quantify OT in plasma from women administered OT during TSL. This is due to increased metabolic clearance of OT in late-stage pregnancy and at the time of childbirth, resulting in extremely low OT plasma concentrations. This study describes the development of an ultra-sensitive bioanalytical method that overcomes the issues previously reported and enables accurate pharmacokinetic analyses of exogenously administered OT in TSL., Methods: A selective and sensitive assay to quantify OT in TSL plasma was developed. Immunoprecipitation (IP) was applied to selectively extract OT from the TSL plasma, thereby generating clean extracts compatible with nanoflow LC (nLC). nLC-MS/MS was chosen for its high sensitivity and ability to differentiate between OT and potentially co-captured OT-like immunoreactive products., Results: The presented methodology is accurate and precise, with a good linear fit between 100-10 000 fg mL -1 OT. TSL plasma samples from a clinical phase 1 study (NCT02999100) were analysed successfully, enabling OT quantification down to 100 fg mL -1 ., Conclusions: The presented IP-nLC-MS/MS method succeeded in overcoming the sensitivity challenge related to the assay of OT in TSL plasma and thereby revealing the PK profiles of OT in TSL plasma clinical study samples., (© 2024 The Author(s). British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

Oxytocin can regulate immunological activity directly or indirectly; however, immunological functions and mechanisms of oxytocin actions under chronic stress like cesarean delivery (CD) are poorly understood. Our study found that abnormal oxytocin production and secretion in CD rats caused atrophy of thymic tissues. Neurotoxin kainic acid microinjected into the dorsolateral supraoptic nucleus in male rats selectively reduced hypothalamic oxytocin levels, increased corticotrophin-releasing hormone and plasma interleukin-1β while reducing plasma oxytocin, thyroxine and testosterone levels and causing atrophy of immune tissues. Thus, plasma oxytocin is essential for immunological homeostasis, which involves oxytocin facilitation of thyroid hormone and sex steroid secretion., Competing Interests: Declaration of competing interest The authors have no competing interests to declare that are relevant to the content of this article., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Oxytocin and cortisol are hormones that can influence cognition and behavior, but the relationships between endogenous concentrations and individual differences in cognitive and behavioral phenotypes remain poorly understood. Across mammals, oxytocin has important roles in diverse social behaviors, and in dogs, it has been implicated in human-oriented behaviors such as social gaze and point-following. Cortisol, an end-product of the hypothalamic-pituitary-adrenal (HPA) axis, is often studied in relation to temperament and emotional reactivity, but it is also known to modulate executive functions. In this study, we measured basal fecal cortisol (n = 247) and plasma oxytocin (n = 249) in dog puppies from a pedigreed population (Canine Companions ®). We collected cognitive and behavioral data from these subjects (n = 247), including measures of human-oriented social cognition, memory, inhibitory control, perceptual discriminations, and temperament. Oxytocin concentrations were estimated to be very highly heritable (h 2 = 0.90-0.99) and cortisol concentrations were estimated to be moderately-highly heritable (h 2 = 0.43-0.47). Bayesian mixed models controlling for relatedness revealed that oxytocin concentrations were positively associated with spatial working memory and displayed a negative quadratic relationship with behavioral laterality, but no credible associations were seen for social measures. Cortisol concentrations exhibited a negative linear relationship with performance on an inhibitory control task and a negative quadratic relationship with bold behavioral reactions to a novel object. Collectively, our results suggest that individual differences in oxytocin and cortisol concentrations are under strong genetic control in dogs and are associated with phenotypic variation in aspects of temperament, behavioral laterality, and executive function., (Copyright © 2024 Elsevier Inc. All rights reserved.)

A mental disorder is a condition that affects an individual's cognition, emotional regulation, or behavior, causing distress or impairing main areas of functioning. The effects of electromagnetic stimulation (EMS) and oxytocin (OXY) on blood corticosterone (CORT) levels in immobilized (10 days, 2 hours a day or one time, 2 hours) male and female rats while accounting for their sex hormone levels were studied. The experiments were conducted on intact and gonadectomized rats. As a result of immobilization, the content of CORT in the blood increased in both groups of rats. Chronic immobilization stress dysregulates HPA axis function in rats of both sexes. Repeated EMS and OXY intranasal (IN OXY) (18 IU) (after each session of immobilization) or intracerebroventricular (1 μl/animal) returned the blood CORT level to normal. The effects of EMS and IN OXY were significant in intact rats compared with gonadectomized rats. EMS and IN OXY enhance the negative feedback of CORT.

The neurohormones oxytocin (OT) and arginine vasopressin (AVP) are involved in social behaviors and psychiatric conditions. However, more research on nonhuman primates with complex social behaviors is needed. We studied two closely-related primate species with divergent social and mating systems; hamadryas baboons (Papio hamadryas, n=38 individuals) and anubis baboons (Papio anubis, n=46). We measured OT in cerebrospinal fluid (CSF, n=75), plasma (n=81) and urine (n=77), and AVP in CSF (n=45), and we collected over 250 hours of focal behavioral observations. Using Bayesian multivariate models, we found no clear species difference in hormone levels; the strongest support was for hamadryas having higher CSF OT levels than anubis (posterior probability [PP] for females = 0.75, males = 0.84). Looking at nine specific behaviors, OT was associated with affiliative behaviors (approach, proximity, grooming, PP ∼ 0.85 - 1.00), albeit inconsistently across sources of measurement (CSF, plasma, and urine, which were uncorrelated with each other). Most behaviors had low repeatability (R ∼ 0 - 0.2), i.e. they did not exhibit stable between-individual differences (or "personality"), and different behaviors did not neatly coalesce into higher-order factors (or "behavioral syndromes"), which cautions against the use of aggregate behavioral measures and highlights the need to establish stable behavioral profiles when testing associations with baseline hormone levels. In sum, we found some associations between peptides and social behavior, but also many null results, OT levels from different sources were uncorrelated, and our behavioral measures did not indicate clear individual differences in sociability., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Environmental exposures may have endocrine disruptor (ED) effects, e.g., a role for halogenated hydrocarbon chlorobenzenes in increasing vasopressin (AVP), oxytocin (OT) secretion and, in association, anxiety and aggression in male rats has been shown. Our aim is to investigate whether 1,2,4-trichlorobenzenehexachlorobenzene= 1:1 (mClB) treatment of female rats also shows ED effects and reproductive biology differences, and whether AVP may have a mediator role in this? Female Wistar rats were treated (0.1; 1.0; 10.0 μg/bwkg/day) with mClB (by gastrictube) and then 30; 60; 90 days after treatment anxiety (open field test) and aggressive (resident intruder test) behaviors AVP, OT concentrations from blood plasma samples were detected by radioimmunoassay on 30; 60; 90 days. Treated female rats were mated with untreated males. Mating success, number of newborn and maternal aggression on the neonates were monitored. Results showed that AVP, OT levels; and anxiety, aggressive behaviors; and mothers' aggression towards their offspring increased significantly in relation to the duration and the dose of mClB treatment. But mating propensity and number of offspring decreased. Patterns of AVP, OT release and anxiety, aggression behaviors, and reproductive-related behaviors were correlated. Consistent with the literature, our studies confirmed the role of AVP and OT in different behavioral effects., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Negative symptoms in the context of psychosis are still poorly understood and diagnosed, which impairs the treatment efficacy of current therapies and patient's integration in society. In this study, we aimed to test hypothesis-based and exploratory associations of negative symptom domains, as defined by the Brief Negative Symptom Scale (BNSS), with hormonal and hematological variables, and, complementarily, with standard psychological/cognitive and psychopathological measures. Fifty-one male patients diagnosed with a psychotic disorder underwent a structured interview and blood collection. Standard Spearmen bivariate correlations were used for data analysis. We obtained evidence of hypothesis-based associations between specific negative symptoms and oxytocin, thyroid stimulating hormone levels and neutrophil-to-lymphocyte ratio; as well as novel and hypothesis-free associations with erythrocyte and lymphocyte count, mean corpuscular volume and red cell distribution width. Complementarily, we also obtained some validation of previous associations of negative symptoms with illness resolution, cognitive symptom severity and social performance, and a novel association with anger contagion. We hope our results can generate new hypotheses in psychosis research. Our work suggests further avenues in research on erythrocytic, inflammatory, thyroid and oxytocin-related markers and abnormalities in psychosis, especially in regards to specific negative symptoms, towards more precise and comprehensive etiological, diagnostic and therapeutic models., Competing Interests: Declaration of competing interest All authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Postweaning is a pivotal period for brain development and individual growth. As an important chemical used in medicines, foods and beverages, sodium citrate (SC) is commonly available. Although some effects of SC exposure on individual physiology have been demonstrated, the potential long-lasting effects of postweaning dietary SC exposure on social behaviours are still elusive., Methods: Both postweaning male and female C57BL/6 mice were exposed to SC through drinking water for a total of 3 weeks. A series of behavioural tests, including social dominance test (SDT), social interaction test (SIT), bedding preference test (BPT) and sexual preference test (SPT), were performed in adolescence and adulthood. After these tests, serum oxytocin (OT) levels and gut microbiota were detected., Results: The behavioural results revealed that postweaning SC exposure decreased the social dominance of male mice in adulthood and female mice in both adolescence and adulthood. SC exposure also reduced the sexual preference rates of both males and females, while it had no effect on social interaction behaviour. ELISA results indicated that SC exposure decreased the serum OT levels of females but not males. 16S rRNA sequencing analysis revealed a significant difference in β-diversity after SC exposure in both males and females. The correlation coefficient indicated the correlation between social behaviours, OT levels and dominant genera of gut microbiota., Conclusion: Our findings suggest that postweaning SC exposure may have enduring and sex-dependent effects on social behaviours, which may be correlated with altered serum OT levels and gut microbiota composition., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Oxytocin has been proposed to possess glucose-stabilizing effects through the release of insulin and glucagon from the pancreas. Also, exogenous oxytocin has been shown to stimulate extrapancreatic glucagon secretion in depancreatized dogs. Here, we investigated the effect of exogenous oxytocin on circulating levels of pancreatic and gut-derived glucose-stabilizing hormones (insulin [measured as C-peptide], glucagon, glucagon-like peptide 1 [GLP-1], and glucose-dependent insulinotropic polypeptide). We studied nine pancreatectomized (PX) patients and nine healthy controls (CTRLs) (matched on age and body mass index) before, during, and after an intravenous infusion of 10 IU of oxytocin administered over 12 min. Oxytocin did not increase plasma glucagon levels, nor induce any changes in plasma glucose, C-peptide, or GIP in any of the groups. Oxytocin decreased plasma glucagon levels by 19 ± 10 % in CTRLs (from 2.0 ± 0.5 [mean ± SEM] to 1.3 ± 0.2 pmol/l, P = 0.0025) and increased GLP-1 by 42 ± 22 % in PX patients (from 9.0 ± 1.0-12.7 ± 1.0 pmol/l, P = 0.0003). Fasting plasma glucose levels were higher in PX patients compared with CTRLs (13.1 ± 1.1 vs. 5.1 ± 0.1 mmol/l, P < 0.0001). In conclusion, the present findings do not support pancreas-mediated glucose-stabilizing effects of acute oxytocin administration in humans and warrant further investigation of oxytocin's gluco-metabolic effects., Competing Interests: Declaration of Competing Interest None of the authors declare conflicts of interests in relation to the present manuscript., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Hormones are specific molecules measured in biological fluids by elaborate analytical systems requiring meticulous attention. Variation between laboratories can be expected. However, recently published measurements of AVP, OXT, and BNP in human plasma under basal/control conditions include numbers which, between publications, vary by 100-10 000-fold. Generally, the methods descriptions are scant, at best, and provide no information about quality control measures. Clearly, two results describing the same basal hormone concentration by numbers three orders of magnitude apart are incongruent providing reason for concern. Basal concentrations of bioactive AVP, OXT, and BNP in human plasma are in the order of 1-10 pmol/L. Therefore, assay systems applied to plasma must be able to measure concentrations of less than 1 pmol/L with appropriate specificity and accuracy. Basal concentrations of AVP, OXT, and BNP above 100 pmol/L should be reconsidered, as such results do not reflect bioactive hormone levels in humans, rats, or mice. Any concentration above 1000 pmol/L is of concern because such levels of bioactive hormone may be seen only under extreme conditions, if at all., (© 2024 The Author(s). Acta Physiologica published by John Wiley & Sons Ltd on behalf of Scandinavian Physiological Society.)

Previous studies have suggested that the effects of androgens on body weight (BW) and appetite are affected by the estrogen milieu in females; however, the mechanism underlying these effects remains unclear. We hypothesized that androgens may affect endogenous oxytocin (OT), which is a hypothalamic anorectic factor, and that these effects of androgens may be altered by the estrogen milieu in females. To investigate this hypothesis, in the present study, we examined the effects of testosterone on peripheral and central OT levels in ovariectomized female rats that did or did not receive estradiol supplementation. Ovariectomized female rats were randomly divided into non-estradiol-supplemented or estradiol-supplemented groups, and half of the rats in each group were concurrently supplemented with testosterone (i.e., rats were divided into four groups, n = 7 per each group). We also measured peripheral and central OT receptor (OTR) gene expression levels. As a result, we found that testosterone increased serum and hypothalamic OT levels and OT receptor mRNA levels in non-estradiol-supplemented rats, whereas it had no effects on these factors in estradiol-supplemented rats. In addition, testosterone reduced food intake, BW gain, and fat weight in non-estradiol-supplemented rats, whereas it did not have any effects on BW, appetite, or fat weight in estradiol-supplemented rats. These findings indicate that the effects of androgens on OT may be affected by the estrogen milieu, and elevated OT levels may be related to the blunting of appetite and prevention of obesity under estrogen-deficient conditions.

Purpose: It was reported that maternal-infant bonding failure predicts abusive parenting. Maternal-infant bonding is important to prevent child abuse. This study aimed to investigate the association between prenatal depressive symptoms, anxiety, cortisol, and oxytocin levels, and postnatal maternal-infant bonding., Methods: The participants completed a self-report prenatal questionnaire that included the Edinburgh Postnatal Depression Scale (EPDS) and State-Trait Anxiety Inventory (STAI) in the second trimester. Blood and saliva were collected in the second trimester. Cortisol levels were measured in plasma, while oxytocin levels were measured in saliva. Postnatal questionnaires, including the Mother-to-Infant Bonding Scale (MIBS), were administered at 2-5 days, 1 month, and 3 months postpartum. Multiple linear regression and generalized estimating equation (GEE) were conducted for analysis., Results: Sixty-six primiparas participated in the study. Prenatal depressive symptoms (EPDS ≥ 9) and anxiety (STAI-S ≥ 42) were observed in 21.2% and 28.8% of the participants, respectively. The median cortisol and oxytocin levels were 21.0 µg/dL and 30.4 pg/mL, respectively. Multivariate linear regression showed that postnatal social support, prenatal depressive symptoms, anxiety, and salivary oxytocin levels predicted MIBS scores at 2-5 days postpartum. At 1 month postpartum, household income, history of miscarriage, postnatal social support, and prenatal anxiety predicted MIBS scores. At 3 months postpartum, only postnatal social support predicted MIBS scores. The results of GEE showed that prenatal anxiety, oxytocin levels, postpartum period, household income, and postpartum social support were associated with MIBS scores., Conclusion: Prenatal depressive symptoms, anxiety, and lower salivary oxytocin levels were predicted to worsen maternal-infant bonding at 2-5 days postpartum. Prenatal anxiety was predicted to cause the same 1 month postpartum. Measuring prenatal depressive symptoms, anxiety, and salivary oxytocin levels may render the assessment of the risk of maternal-infant bonding failure during the early postpartum period and intervene during pregnancy possible., (© 2024. The Author(s).)

Oxytocin (OT) is a neuropeptide that primarily functions as a hormone controlling female reproductive processes. Since numerous recent studies have shown that single and repetitive administrations of OT increase trust, social interaction, and maternal behaviors in humans and animals, OT is considered a key molecule that regulates social memory and behavior. Furthermore, OT binds to receptors for advanced glycation end-products (RAGE), and it has been demonstrated that loss of RAGE in the brain vascular endothelial cells of mice fails to increase brain OT concentrations following peripheral OT administration. This leads to the hypothesis that RAGE is involved in the direct transport of OT, allowing it access to the brain by transporting it across the blood-brain barrier; however, this hypothesis is only based on limited evidence. Herein, we review the recent results related to this hypothesis, such as the mode of transport of OT in the blood circulation to the brain via different forms of RAGE, including membrane-bound full-length RAGE and soluble RAGE. We further review the modulation of brain function and social behavior, which seem to be mediated by RAGE-dependent OT. Overall, this review mostly confirms that RAGE enables the recruitment of circulating OT to the brain, thereby influencing social behavior. The requirement for further studies considering the physiological aspects of RAGE is also discussed., Competing Interests: Declaration of Competing Interest The authors declare they have no competing interests., (Copyright © 2024. Published by Elsevier Inc.)

Polyuria-polydipsia syndrome can be caused by central diabetes insipidus, nephrogenic diabetes insipidus or primary polydipsia. To avoid confusion with diabetes mellitus, the name 'central diabetes insipidus' was changed in 2022 to arginine vasopressin (AVP) deficiency and 'nephrogenic diabetes insipidus' was renamed as AVP resistance. To differentiate the three entities, various osmotic and non-osmotic copeptin-based stimulation tests have been introduced in the past decade. The hypertonic saline test plus plasma copeptin measurement emerged as the test with highest diagnostic accuracy, replacing the water deprivation test as the gold standard in differential diagnosis of the polyuria-polydipsia syndrome. The mainstay of treatment for AVP deficiency is AVP replacement with desmopressin, a synthetic analogue of AVP specific for AVP receptor 2 (AVPR2), which usually leads to rapid improvements in polyuria and polydipsia. The main adverse effect of desmopressin is dilutional hyponatraemia, which can be reduced by regularly performing the so-called desmopressin escape method. Evidence from the past few years suggests an additional oxytocin deficiency in patients with AVP deficiency. This potential deficiency should be further evaluated in future studies, including feasible provocation tests for clinical practice and interventional trials with oxytocin substitution., (© 2024. Springer Nature Limited.)

Previous studies support links among maternal-fetal attachment, psychological symptoms, and hormones during pregnancy and the post-partum period. Other studies connect maternal feelings and behaviors to oxytocin and suggest that an increase in oxytocin during pregnancy may prime maternal-fetal attachment. To date, researchers have not examined a possible association between maternal-fetal attachment with human placental lactogen although animal models are suggestive. In the current study, we sought to describe oxytocin and human placental lactogen levels as related to psychological constructs across pregnancy. Seventy women participated in the study. At each of three time-points (early, mid, and late pregnancy), the women had their blood drawn to assess oxytocin and human placental lactogen levels, and they completed psychological assessments measuring maternal-fetal attachment, anxiety, and depression. Our results indicate that oxytocin levels were statistically similar across pregnancy, but that human placental lactogen significantly increased across pregnancy. Results did not indicate significant associations of within-person (comparing individuals to themselves) oxytocin or human placental lactogen levels with maternal-fetal attachment. Additionally, results did not show between-person (comparing individuals to other individuals) oxytocin or human placental lactogen levels with maternal-fetal attachment. Oxytocin levels were not associated with anxiety; rather the stage of pregnancy moderated the effect of the within-person OT level on depression. Notably, increasing levels of human placental lactogen were significantly associated with increasing levels of both anxiety and depression in between subject analyses. The current study is important because it describes typical hormonal and maternal fetal attachment levels during each stage of pregnancy, and because it suggests an association between human placental lactogen and psychological symptoms during pregnancy. Future research should further elucidate these relationships., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Postpartum depression (PPD) is a common mental disorder in postpartum women, negatively impacting physical and mental health. Correlation analysis can predict the relationship between variables. By detecting the abnormal level of oxytocin, clinicians can timely know the emotional states of parturients to guide clinical practice. This study aimed to investigate the relationship between emotional states and oxytocin (OT) levels in patients with PPD., Materials and Methods: The medical records of 166 PPD patients admitted to Cangzhou Central Hospital from May 2020 to March 2023 were retrospectively analyzed. After excluding 9 patients who did not meet the inclusion criteria, the remaining 157 patients were included in this study. The 7-item Generalized Anxiety Disorder Scale and Patient Health Questionaire-9 items were used to evaluate the emotional states of 157 patients, and the included subjects were grouped according to the results of the scale. The serum OT levels of patients was measured, and the relationship between the OT levels and emotional states was analyzed., Results: In this study, 75 patients were included in the mild anxiety group, and 82 patients were included in the moderate and severe anxiety group. Seventy-nine patients were selected as the mild depression group, and 78 patients were included in the moderate and severe depression group. The mild anxiety group had a higher OT level than the moderate and severe anxiety group (Z = -10.121, p < 0.001). The mild depression group had a higher OT level than the moderate and severe depression group (Z = -9.758, p < 0.001). OT level was negatively correlated with anxiety and depression scores (r = -0.676, r = -0.665, p < 0.001)., Conclusion: There is a specific relationship between the emotional states of PPD patients and the OT levels in the body, and active clinical management strategies need to be implemented.

Introduction: Dysfunctions in the oxytocin system have been reported in patients with borderline personality disorder (BPD). Deficits could be related to interpersonal hypersensitivity, which has been previously associated with failures in social cognition (SC) in this disorder, especially in Theory of Mind (ToM) skills. The aim of this work is to study the links between the oxytocin system and SC impairments in patients with BPD., Method: Plasma oxytocin levels (OXT) and protein expression of oxytocin receptors in blood mononuclear cells (OXTR) were examined in 33 patients with a diagnosis of BPD (age: M 28.85, DT = 8.83). Social cognition was assessed using the Movie for the Assessment of Social Cognition (MASC). Statistical associations between biochemical factors and different response errors in MASC were analyzed through generalized linear regression controlling for relevant clinical factors., Results: Generalized linear regression showed a significant relationship between lower OXTR and overmentalization in BPD patients (OR = 0.90)., Conclusions: This work supports the relationship between alterations in the oxytocin system and ToM impairments observed in BPD patients, enhancing the search for endophenotypes related to the phenotypic features of the disorder to improve current clinical knowledge and address more specific therapeutic targets., (© 2024 The Authors. Acta Psychiatrica Scandinavica published by John Wiley & Sons Ltd.)

Background: Given its putative roles in mediating prosocial behavior, attachment bonds, and stress physiology, oxytocin modulation has been hypothesized to be a biological correlate of the salubrious effects of meditation practice. Here we investigated the effects of a month-long silent meditation retreat on changes in oxytocin, and the related hormone and vasopressin, in relation to psychosocial changes in attachment style, anxiety, personality measures, and feelings of social connectedness with fellow meditators., Methods: Plasma oxytocin and vasopressin and self-report questionnaires were measured in retreat participants ( n = 28) at the beginning of, and 3 weeks into, a residential meditation retreat. Control participants ( n = 34), who were similar in age, gender, and meditation experience, were also assessed across a 3-week interval. Linear mixed effects models were used to assess outcomes., Results: The retreat group showed a small but significant decrease in oxytocin compared to controls who showed no change. In the retreat group, higher openness to experience at Time 1 predicted greater reductions in oxytocin during the retreat, and lower oxytocin at Time 2 was related to stronger feelings of personal connection with fellow meditators. The changes in oxytocin were not related to attachment style or anxiety. Vasopressin decreased over time across both groups, suggesting no specific effect of retreat., Conclusion: These preliminary findings suggest that meditation training in the context of a silent residential retreat may reduce circulating levels of oxytocin. We interpret this finding from multiple theoretical perspectives, discussing key measurement limitations and proposing future study designs that may help to differentiate the effects of different meditation practices and contexts on oxytocin signaling., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Conklin, Zanesco, King, Epel and Saron.)

Menopause marks the cessation of fertility and the transition to post-reproductive years. Nearly 1 million US women experience menopause annually, but despite the significant impact it has on their physical and mental health, menopause has been insufficiently studied. Oxytocin is a neurohormone that regulates emotionality, social behaviors, and fundamental physiological systems. Localization of oxytocin receptors in the brain, reproductive tissues, bone, and heart support their role in mental health and potentially sleep, along with reproductive and cardiovascular functions. While experimental data linking oxytocin to behavior and physiology in animals are largely consistent, human data are correlative and inconclusive. As women transition into menopause, oxytocin levels decrease while their susceptibility to mood disorders, poor sleep, osteoporosis, and cardiovascular diseases increases. These concurrent changes highlight oxytocin as a potential influence on the health and mood of women along their reproductive life span. Here, we summarize experimental rodent and non-human primate studies that link oxytocin to reproductive aging and metabolic health and highlight the inconclusive findings in studies of women. Most human studies relied on a single oxytocin assessment in plasma or on intranasal oxytocin administration. The pulsatile release and short half-life of plasma oxytocin limit the validity of these methods. We discuss the need for oxytocin assessments in stable bio-samples, such as urine, and to use valid assays for assessment of associations between changing oxytocin levels and well-being across the reproductive life span. This work has the potential to guide therapeutic strategies that will one day alleviate adverse health outcomes for many women.

Purpose: We evaluated whether repeated high-intensity interval exercise (HIIE) influences plasma oxytocin (OT) concentration in healthy men, and, given that OT is mainly synthesized in the hypothalamus, we assessed the concentration difference between the arterial (OT ART ) versus the internal jugular venous OT concentration (OT IJV ). Additionally, we hypothesized that an increase in cerebral OT release and the circulating concentration would be augmented by repeated HIIE., Methods: Fourteen healthy men (age = 24 ± 2 yr; mean ± SD) performed two identical bouts of HIIE. These HIIE bouts included a warm-up at 50%-60% maximal workload ( Wmax ) for 5 min followed by four bouts of exercise at 80%-90% Wmax for 4 min interspersed by exercise at 50%-60% Wmax for 3 min. The HIIE bouts were separated by 60 min of rest. OT was evaluated in blood through radial artery and internal jugular vein catheterization., Results: Both HIIE bouts increased both OT ART (median [IQR], from 3.9 [3.4-5.4] to 5.3 [4.4-6.3] ng·mL -1 in the first HIIE, P < 0.01) and OT IJV (from 4.6 [3.4-4.8] to 5.9 [4.3-8.2] ng·mL -1 , P < 0.01), but OT ART-IJV was unaffected (from -0.24 [-1.16 to 1.08] to 0.04 [-0.88 to 0.78] ng·mL -1 , P = 1.00). The increased OT levels were similar in the first and second HIIE bouts (OT ARTP = 0.25, OT IJVP = 0.36)., Conclusions: Despite no change in the cerebral OT release via the internal jugular vein, circulating OT increases during HIIE regardless of the accumulated exercise volume, indicating that OT may play role as one of the exerkines., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American College of Sports Medicine.)

Objective: This study aimed to investigate the relationship between maternal serum lipid parameters and oxytocin requirements among women with term vaginal deliveries., Study Design: In this secondary analysis of a prospective cohort study, women who presented for delivery at ≥37 weeks' gestation and received oxytocin during their labor were included. Maternal serum was collected intrapartum. The cohort was stratified into two groups based on maximum oxytocin infusion dose during labor. Primary outcomes were maternal total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride levels. Generalized linear regression models were used to assess the association between lipid parameters and maximum oxytocin dose requirements while controlling for potential confounders. For secondary analyses, the cohort was stratified by HDL-C into two groups. Multivariable logistic regression was used to evaluate the relationship between low maternal HDL-C and additional intrapartum oxytocin parameters., Results: There were no differences in maternal total cholesterol, LDL-C, or triglyceride values between high and low maximum oxytocin groups. Median serum HDL-C was significantly lower among women in the high oxytocin group compared with those in the low oxytocin group (56 vs. 62 mg/dL, p  < 0.01). For every 0.26 mg/dL lower HDL-C, women had 1 mU/min higher maximum oxytocin infusion dose during labor. Women with low serum HDL-C were also more likely to require maximum oxytocin doses above the 75th percentile (adjusted odds ratio [aOR]: 1.99, 95% confidence interval [CI]: 1.06-3.75) and above the 90th percentile (aOR: 2.47, 95% CI: 1.10-5.54). Among women undergoing induction of labor, low serum HDL-C was also associated with longer duration of oxytocin infusion (aOR: 2.07, 95% CI: 1.02-4.20)., Conclusion: Low maternal HDL-C levels at term are associated with higher maximum oxytocin infusion doses among women undergoing labor induction or augmentation. Given the growing prevalence of metabolic syndrome in the United States and persistently high rates of cesarean delivery, HDL-C or its components may present a new target for predicting and improving labor outcomes., Key Points: · Serum HDL-C at term is inversely correlated with oxytocin infusion doses at term.. · Low maternal serum HDL-C is associated with higher oxytocin requirements during labor induction or augmentation.. · No association between maternal serum total cholesterol, LDL-C, or triglyceride levels and oxytocin requirements in labor.., Competing Interests: None declared., (Thieme. All rights reserved.)

Lactation relies on the secretion of two key hormones, prolactin and oxytocin. Studies have shown that yoga in the postpartum period can stimulate feelings of comfort and relaxation, which increases oxytocin production. The aim of this study was to evaluate the effect of yoga training on postpartum prolactin and oxytocin levels in a group of primipara women. This quasi-experimental study included 60 healthy primigravida, primipara women in their third trimester who attended antepartum and postpartum care at four primary healthcare centers in Kediri Regency. The participants were randomly allocated to an intervention group ( n = 30) and a control ( n = 30) group. The intervention group received health education and participated at eight yoga sessions with a duration of 60 min, from week 32 of gestation until the postpartum period. The control group received standard antepartum and postpartum care. Prolactin and oxytocin levels were measured in weeks 1 and 6 postpartum. Mean prolactin increment was significantly higher in the intervention group (176.8 ± 66.6 ng/ml) than the control group (24.8 ± 39.5 ng/ml). Similarly, mean oxytocin increment was significantly higher in the intervention group (58.6 ± 31.59 pg/ml) than the control group (14.6 ± 36.06 pg/ml). Our results suggest that yoga training in the third trimester until the postpartum period increases prolactin and oxytocin levels among primipara postpartum women., Competing Interests: The authors declare no conflict of interest., (© 2024 by the authors.)

Introduction: In nurturing systems, the oxytocin (Oxt)-oxytocin receptor (Oxtr) system is important for parturition, and essential for lactation and parental behavior. Among the nerve nuclei that express Oxtr, the lateral septal nucleus (LS) and medial preoptic area (MPOA) are representative regions that control maternal behavior., Methods: We investigated the role of Oxtr- and Oxtr-expressing neurons, located in the LS and MPOA, in regulating maternal behavior by regulating Oxtr expression in a region-specific manner using recombinant mice and adeno-associated viruses. We quantified the prolactin (Prl) concentrations in the pituitary gland and plasma when Oxtr expression in the MPOA was reduced., Results: The endogenous Oxtr gene in the neurons of the LS did not seem to play an essential role in maternal behavior. Conversely, decreased Oxtr expression in the MPOA increased the frequency of pups being left outside the nest and reduced their survival rate. Deletion of Oxtr in MPOA neurons prevented elevation of Prl levels in plasma and pituitary at postpartum day 2., Discussion/conclusion: Oxtr-expressing neurons in the MPOA are involved in the postpartum production of Prl. We confirmed the essential functions of Oxtr-expressing neurons and the Oxtr gene itself in the MPOA for the sustainability of maternal behavior, which involved Oxtr-dependent induction of Prl., (© 2023 The Author(s). Published by S. Karger AG, Basel.)

Oxytocin (OT) regulates food intake and body weight, particularly in obese individuals. Decreases in the effects of OT have recently been implicated in metabolic disturbances, and the administration of estradiol (E2) increased serum OT levels. Although weight gain is frequently observed in perimenopausal women, endogenous OT levels remain unclear. Therefore, we herein compared endogenous levels of hypothalamic and serum OT between young and middle-aged perimenopausal female rats and examined the relationship between serum estrogen and leptin levels. Body weight and visceral and subcutaneous fat weights were higher in middle-aged rats. Although no significant differences were observed in serum OT and E2 levels, serum leptin levels and hypothalamic mRNA levels of OT and the OT receptor (OTR) were significantly higher in middle-aged rats than in young rats. Serum OT levels did not correlate with hypothalamic OT mRNA levels or serum E2 levels. E2 maintains serum OT levels in perimenopausal rats, and other factors may elevate hypothalamic OT/OTR mRNA levels. Increases in body and fat weights in perimenopausal rats may be attributed to factors other than OT. Therefore, the administration of OT alone may not be sufficient to prevent metabolic disorders induced by the perimenopausal status. J. Med. Invest. 71 : 246-250, August, 2024.

Background: Dementia encompasses a range of neurodegenerative disorders characterized by cognitive decline and functional impairment. The identification of reliable biomarkers is essential for accurate diagnosis and gaining insights into the mechanisms underlying diseases., Objective: This study aimed to investigate the plasma biomarker profiles associated with Brain- Derived Neurotrophic Factor (BDNF), Oxytocin, Neuronal Pentraxin-1 (NPTX1), Triggering Receptor Expressed on Myeloid Cells 2 (TREM2), Tumor Necrosis Factor-alpha (TNF-alpha), Interleukin- 1 (IL-1) and Prolactin in Alzheimer's disease (AD), dementia with Lewy bodies (DLB), frontotemporal dementias (FTD) and healthy controls., Methods: Serum levels of the aforementioned biomarkers were analyzed in 23 AD, 28 DLB, 15 FTD patients recruited from outpatient units and 22 healthy controls. Diagnostic evaluations followed established criteria and standardized clinical tests were conducted. Blood samples were collected and analyzed using ELISA and electrochemiluminescence immunoassay methods., Results: Serum BDNF and oxytocin levels did not significantly differ across groups. NPTX1, TREM2, TNF-alpha and IL-1 levels also did not show significant differences among dementia groups. However, prolactin levels exhibited distinct patterns, with lower levels in male DLB patients and higher levels in female AD patients compared to controls., Conclusion: The study findings suggest potential shared mechanisms in dementia pathophysiology and highlight the importance of exploring neuroendocrine responses, particularly in AD and DLB. However, further research is warranted to elucidate the role of these biomarkers in dementia diagnosis and disease progression., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: The clinical debut of schizophrenia is frequently a first episode of psychosis (FEP). As such, there is considerable interest in identifying associations between biological markers and clinical or cognitive characteristics that help predict the progression and outcome of FEP patients. Previous studies showed that high prolactin, low oxytocin, and high homocysteine are factors associated with FEP 6 months after diagnosis, at which point plasma levels were correlated with some clinical and cognitive characteristics., Methods: We reexamined 75 patients at 12 months after diagnosis to measure the evolution of these molecules and assess their association with clinical features., Results: At follow-up, FEP patients had lower prolactin levels than at baseline, and patients treated with risperidone or paliperidone had higher prolactin levels than patients who received other antipsychotic agents. By contrast, no changes in oxytocin and homocysteine plasma levels were observed between the baseline and follow-up. In terms of clinical features, we found that plasma prolactin and homocysteine levels were correlated with the severity of the psychotic symptoms in male FEP patients, suggesting that they might be factors associated with psychotic symptomatology but only in men. Together with oxytocin, these molecules may also be related to sustained attention, verbal ability, and working memory cognitive domains in FEP patients., Conclusion: This study suggests that focusing on prolactin, oxytocin, and homocysteine at a FEP may help select adequate pharmacological treatments and develop new tools to improve the outcome of these patients, where sex should also be borne in mind., (© The Author(s) 2023. Published by Oxford University Press on behalf of CINP.)

Substance use disorders have been associated with alterations in the oxytocinergic system, but few studies have investigated both the peptide and epigenetic mechanisms potentially implicated in the regulation of oxytocin receptor. In this study, we compared plasma oxytocin and blood DNA methylation in the OXTR gene between people with and without cocaine use disorder (CUD). We measured the oxytocin levels of 51 people with CUD during acute abstinence and of 30 healthy controls using an enzyme immunoassay. The levels of DNA methylation in four CpG sites at exon III of the OXTR gene were evaluated in a subsample using pyrosequencing. The Addiction Severity Index was used to assess clinical characteristics. We found higher oxytocin levels in men with CUD (56.5 pg/mL; 95% CI: 48.2-64.7) than in control men (33.6 pg/mL; 95% CI: 20.7-46.5), while no differences between women with and without CUD were detected. With a moderate effect size, the interaction effect between group and sex remained significant when controlling for height, weight and age data. A positive correlation in the CUD sample was found between oxytocin levels and days of psychological suffering prior to treatment enrollment. No group differences were observed regarding DNA methylation data. This suggests that CUD is associated with higher peripheral oxytocin levels in men during acute abstinence. This finding may be considered in future studies that aim at using exogenous oxytocin as a potential treatment for cocaine addiction., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Although the role of oxytocin in the pathophysiology of sepsis is still unknown, rising preclinical evidence suggests that oxytocin is possibly involved. However, no direct clinical studies have measured the levels of oxytocin during sepsis. In this preliminary study, the serum oxytocin levels were evaluated throughout the duration of sepsis., Method: Twenty-two male patients over 18 years of age with a SOFA score of 2 points or more who were admitted to the ICU were included. Patients with a history of neuroendocrine, psychiatric, and neurologic disorders, cancer, an infection caused by COVID-19, shock due to reasons other than sepsis, a history of psychiatric or neurologic medication use, and those who died during the study were excluded. The main endpoint included the measurement of serum oxytocin levels using radioimmunoassay at 6, 24, and 48 h of the ICU admission., Results: Mean serum oxytocin level was higher at 6 h of ICU admission (41.27 ± 13.14 ng/L) than after 24 and 48 h of ICU admission (22.63 ± 5.75 and 20.97 ± 7.61 ng/L respectively) ( P -value < .001)., Conclusion: Our study, while reporting increased serum oxytocin levels in the initial phase of sepsis and decline afterward, supports the possible contribution of oxytocin in the pathophysiology of sepsis. Given that oxytocin seems to modulate the innate immune system, future investigations are necessary to assess the potential role of oxytocin in the pathophysiology of sepsis., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Affectionate touch, which is vital for mental and physical health, was restricted during the Covid-19 pandemic. This study investigated the association between momentary affectionate touch and subjective well-being, as well as salivary oxytocin and cortisol in everyday life during the pandemic., Methods: In the first step, we measured anxiety and depression symptoms, loneliness and attitudes toward social touch in a large cross-sectional online survey (N = 1050). From this sample, N = 247 participants completed ecological momentary assessments over 2 days with six daily assessments by answering smartphone-based questions on affectionate touch and momentary mental state, and providing concomitant saliva samples for cortisol and oxytocin assessment., Results: Multilevel models showed that on a within-person level, affectionate touch was associated with decreased self-reported anxiety, general burden, stress, and increased oxytocin levels. On a between-person level, affectionate touch was associated with decreased cortisol levels and higher happiness. Moreover, individuals with a positive attitude toward social touch experiencing loneliness reported more mental health problems., Conclusions: Our results suggest that affectionate touch is linked to higher endogenous oxytocin in times of pandemic and lockdown and might buffer stress on a subjective and hormonal level. These findings might have implications for preventing mental burden during social contact restrictions., Funding: The study was funded by the German Research Foundation, the German Psychological Society, and German Academic Exchange Service., Competing Interests: ES, DH, CA, DS, AN, US, RH, ME, BD No competing interests declared, (© 2023, Schneider et al.)

Background: Depressive symptomatology is prevalent among female university students with adverse effects on their quality of life and academic performance. Previous research suggested associations between depressive symptomatology and oxytocin levels and between depressive symptomatology and Temperament Traits. Despite this evidence, to the best of our knowledge no research has studied the effects fboth oxytocin serum levels and temperament dimensions on depressivesymptoms in a healthy sample. The present study aimed to analyse the effect of oxytocin levels and temperament traits on depressive symptomatology in healthy female university students., Methods: All participants completed the Beck Depression Inventory and the Adult Temperament Questionnaire. Blood samples were collected between 8 and 8H30 a.m. after 12 h of fasting and between 5 and 8 day of the menstrual cycle and serum oxytocin levels were quantified using a commercial enzyme-linked immunosorbent assay. A hierarchical multiple regression model using a stepwise method was conducted to identify predictors of depression., Results: Forty-five women aged between 18 and 25 years old (19.37 ± 1.32 years) volunteered to participate in this study. Depressive symptomatology was negatively associated with oxytocin serum levels and "Negative affect" and positively associated with "Effortful control" and "Activation Control". In the final regression model, only oxytocin level was a predictor (B = - 0.090, p < 0.0001), the model explaining 65.2% of the depression variation. Oxytocin played a mediation role between "Negative affects" and Depressive symptomatology., Conclusions: Our results showed that oxytocin level, rather than personality dimensions, was associated with depressive symptomatology. These results highlight the relevance of the discussion on the use of oxytocin as a biological marker of emotional and social symptoms that characterize depression., (© 2022. The Author(s).)