Salivary cortisol responses to acute stress vary between allergic and healthy individuals: the role of plasma oxytocin, emotion regulation strategies, reported stress and anxiety

Validation of two immunoassays for oxytocin measurements in human saliva

The objective of this research was to develop and validate two immunoassays for oxytocin measurement in human saliva, one using a monoclonal and the other a polyclonal antibody against oxytocin, whose affinity for oxytocin was tested by an antibody mapping epitope analysis. These assays were analytically validated and used to compare oxytocin concentrations with those obtained with a commercial kit before and after the extraction or reduction/alkylation (R/A) treatments to saliva samples. The assays were also used to evaluate changes in salivary oxytocin concentrations following a physical effort and an induced psychological stress, which have previously been described as situations that cause an increase in salivary oxytocin. Both assays showed to be precise and accurate in the validation studies, and the antibodies used showed a defined binding region in case of the monoclonal antibody, whereas the polyclonal antibody showed binding events through all the oxytocin sequence. Although the monoclonal and polyclonal assays showed a positive correlation, they give results in a different range of magnitude. Both assays showed significant increases in oxytocin concentrations when applied after the physical effort and the psychological stress. This study shows that a variability in the reported values of oxytocin can occur depending on the assay and indicates that the use of different types of antibodies can give a different range of values when measuring oxytocin in saliva.

Advances in human oxytocin measurement: challenges and proposed solutions

Oxytocin, a neuropeptide known for its role in reproduction and socioemotional processes, may hold promise as a therapeutic agent in treating social impairments in patient populations. However, research has yet to uncover precisely how to manipulate this system for clinical benefit. Moreover, inconsistent use of standardized and validated oxytocin measurement methodologies-including the design and study of hormone secretion and biochemical assays-present unresolved challenges. Human studies measuring peripheral (i.e., in plasma, saliva, or urine) or central (i.e., in cerebrospinal fluid) oxytocin concentrations have involved very diverse methods, including the use of different assay techniques, further compounding this problem. In the present review, we describe the scientific value in measuring human endogenous oxytocin concentrations, common issues in biochemical analysis and study design that researchers face when doing so, and our recommendations for improving studies using valid and reliable methodologies.

Psychological suzhi moderates state anxiety and heart rate responses to acute stress in male adolescents

Psychological suzhi has increasingly been recognized to buffer chronic stress and improve mental health. However, few studies have examined the role of psychological suzhi in the response to acute stress. The current study aimed to investigate whether psychological suzhi can buffer state anxiety and heart rate responses to acute stress in adolescents. Healthy male adolescents (N = 63) were classified into high (N = 30) or low (N = 33) psychological suzhi groups based on the Chinese norm of adolescent psychological suzhi scale-simplified version. They completed both the modified Trier Social Stress Test for Groups and a specific control condition, with heart rate and state anxiety assessed. Data were analysed with mixed-design repeated measures analysis of variance. The results showed that the modified Trier Social Stress Test for Groups condition effectively induced an increase in state anxiety and heart rate. Furthermore, individuals with higher levels of psychological suzhi showed lower state anxiety and heart rate stress responses. The present study indicated that psychological suzhi is an important internal resource against acute stress, which may inform interventions for male adolescents exposed to acute stress.

Psychophysiological mechanisms underlying the potential health benefits of human-dog interactions: A systematic literature review

While the symbiotic nature of human-dog relationships and perceived benefits to human health have attracted much scientific interest, the mechanisms through which human-dog interactions may confer health benefits to humans are still poorly understood. The aim of this systematic literature review was to synthesize evidence of physiological changes associated with human-dog interactions with relevance to human health. Electronic databases were systematically searched (PubMed, MEDLINE with full text, Scopus, PsycINFO, CINAHL Plus with Full Text, and Web of Science Core Collection) for relevant studies. Of the 13,072 studies identified, 129 met the inclusion criteria, with approximately half being randomized trials (Level 2) based on the Oxford Centre for Evidence Based Medicine level system. Measures employed to study human physiological changes associated with human-dog interactions most commonly involved cardiac parameters and hormones, with negligible research of brain activity. The main positive findings were increases in heart rate variability and oxytocin, and decreases in cortisol with human-dog interactions. These physiological indicators are consistent with activation of the parasympathetic nervous system (PNS) and oxytocinergic system (OTS), and down-regulation of hypothalamic-pituitary-adrenal (HPA) axis activity. These results provide evidence of specific pathways through which human-dog contact may confer health benefits, likely through relaxation, bonding, and stress reduction. However, these findings should be interpreted contextually due to limitations and methodological differences. Previous research using other biological variables was limited in quantity and quality, thus impeding firm conclusions on other possible mechanisms. Further research is needed in some psychophysiological domains, particularly electroencephalography, to better understand central nervous system (CNS) effects. The findings of this review have implications for human-dog interactions to positively affect several stress-sensitive physiological pathways and thus confer health benefits. This supports their incorporation in various clinical, non-clinical, and research settings to develop evidence-based interventions and practices for cost-effective and efficacious ways to improve human health.

Effects of High-Frequency Chest Wall Oscillation Expectoration System on Pulmonary Rehabilitation and Cortisol Function in Patients with Severe AECOPD

Objective

To investigate the effect of high-frequency chest wall oscillatory expectoration system (HFCWO) on pulmonary rehabilitation and cortisol function in patients with severe acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

Methods

The 65 severe AECOPD patients admitted to our hospital from January 2019 to May 2020 were divided into group A with 33 cases and group B with 32 cases by random number table method. After 14 days of intervention, the improvement time of clinical symptoms in the two groups was recorded, and blood gas, lung function, inflammatory, and cortisol function-related indicators were evaluated before and after treatment.

Results

The remission time of expectoration, pulmonary signs, and hospital stay in group A were significantly shorter than those in group B (P < 0.05). Compared with before treatment, blood oxygen partial pressure (PaO₂), forced vital capacity (FVC), forced expiratory volume at 1 s (EFV1), and EFV1/FVC increased significantly; blood carbon dioxide partial pressure (PaCO₂), C-reactive protein (CRP), interleukin-6 (IL-6), white blood cell count (WBC), plasma cortisol (COR), and adrenocorticotropic hormone (ACTH) levels were significantly decreased, and the above indicators in group A increased or decreased more significantly than those in group B (P < 0.05); there was no significant difference in tolerance and adverse reactions between the two groups (P > 0.05).

Conclusion

HFCWO has good pulmonary rehabilitation effect in the treatment of severe AECOPD and can significantly improve the blood gas indexes, inflammation, and cortisol function of patients, which is safe and feasible.

Possible oxytocin-related biomarkers in anxiety and mood disorders

Anxiety and mood disorders are prevalent, disabling, and frequently difficult to treat. Such disorders are often comorbid and share similar characteristics. For more accurate diagnosis and improved treatment, a deeper understanding of the pathophysiology of anxiety and mood disorders is important. Oxytocin, a neuropeptide synthesized in the hypothalamus, affects human psychology and behaviors such as social and affiliative behaviors, fear and emotion processing, and stress regulation. Thus, oxytocin is believed to exert anxiolytic and antidepressant-like effects. This review article provides an overview of clinical studies on relationships between the oxytocin system and anxiety and mood disorders, focusing on oxytocin-related biomarker findings. Biomarkers used in such studies include central and peripheral oxytocin levels, analysis of oxytocin-related genes, and expression levels of oxytocin and oxytocin receptor genes in postmortem brains. Although a growing number of studies support the presence of oxytocinergic effects on anxiety and mood disorders, study results are heterogeneous and inconclusive. Moderating factors such as the characteristics of study populations, including sex, age, context, early life adversity, and attachment styles in patient cohorts, might affect the heterogeneity of the study results. Limitations in existing research such as small sample sizes, large dependence on peripheral sources of oxytocin, and inconsistent results between immunoassay methods complicate the interpretation of existing findings.

Discussions and perspectives regarding oxytocin as a biomarker in human investigations

This article introduces a review of research that has implemented oxytocin measurements in different fluids such as plasma, cerebrospinal fluid, urine and, mainly, saliva. The main purpose is to evaluate the level of evidence supporting the measurement of this biomarker implicated in a variety of psychological and social processes. First, a review of the technical developments that allowed the characterization, function establishing, and central and peripheral levels of this hormone is proposed. Then, the article approaches the current discussions regarding the level of reliability of the laboratory techniques that enable the measurement of oxytocin, focusing mainly on the determination of its concentration in saliva through Enzyme-Linked Immunosorbent Assay (ELISA). Finally, research results, which have established the major physiological correlates of this hormone in fields such as social neuroscience and neuropsychology, are collected and discussed in terms of the hormone measurement methods that different authors have used. In this way, the article is expected to contribute to the panorama of debates and current perspectives regarding investigation involving this important biomarker.

Therapy Dog Welfare Revisited: A Review of the Literature

During the past decade, the field of human-animal interaction(s) research has been characterized by a significant increase in scientific findings. These data have contributed to our current understanding of how humans may benefit from contact with animals. However, the animal experience of these interactions is still an under-researched area. This paper addresses the welfare of dogs who participate in animal-assisted interventions (AAIs) to improve health in human recipients. This paper builds on previous work by Glenk (2017) and provides an updated review of the literature on therapy dog welfare published from 2017-2021. New advances in scientific methodology, such as the determination of salivary oxytocin, breath rate and tympanic membrane temperature, are analyzed regarding their value and limitations for research in AAIs. Moreover, welfare-related social and environmental factors (e.g., freedom of choice, exploration of novel environments, inequity aversion, individual development, working experience, relationship with handler and handler skills) that profoundly influence dog perception and well-being are reviewed and discussed. Accounting for the globally increasing interest and the number of dogs utilized in AAIs, safeguarding therapy dog well-being, and identifying situations, circumstances and protocols that may challenge animal welfare remains an emerging and crucial area of scientific effort.

Psychological impact of the COVID-19 pandemic on patients with allergic diseases

BACKGROUND

On March 2020, World Health Organization (WHO) declared COVID-19 to be a pandemic disease. Interactions between allergy-related inflammatory and psychiatric disorders including depression, anxiety, and post-traumatic stress disorder (PTSD) have been documented. Therefore, those who have pre-existing allergic conditions may have an increased psychiatric reaction to the stresses of the COVID-19 pandemic.

OBJECTIVE

Identify the psychological impact of COVID-19 in patients with allergic diseases and determine if these individuals have a greater risk of presenting with post-traumatic stress disorder (PTSD).

METHODS

It is a cross-sectional, survey-based study designed to assess the degree of symptoms of depression and the risk of PTSD using the Patient Health Questionnaire (PHQ-9) and the Impact of Event Scale-Revised (IES-R), respectively, in allergic patients.

RESULTS

A total of 4106 surveys were evaluated; 1656 (40.3%) were patients with allergic disease, and 2450 (59.7%) were non-allergic (control) individuals. Of those with allergies, 76.6% had respiratory allergic disease including asthma and allergic rhinitis. Individuals with allergic disease reported higher scores regarding symptoms of PTSD on the IES-R scale (p = 0.052, OR 1.24 CI 0.99-1.55) as well as a higher depression risk score in the PHQ-9 questionnaire (mean 6.82 vs. 5.28) p = 0.000 z = -8.76.The allergy group presented a higher score in the IES-R questionnaire (mean 25.42 vs. 20.59), being more susceptible to presenting PTSD (p = 0.000, z = -7.774).The individuals with allergic conditions were further divided into subgroups of those with respiratory allergies such as allergic rhinitis and asthma vs those with non-respiratory allergies such as drug and food allergy, urticaria and atopic dermatitis. This subgroup analysis compares respiratory versus non-respiratory allergic patients, with similar results on the IES-R (mean 25.87 vs 23.9) p = 0.0124, z = -1.539. There was no significant difference on intrusion (p = 0.061, z = -1.873) and avoidance (p = 0.767, z = -0.297), but in the hyperarousal subscale, patients with respiratory allergy had higher scores (mean 1.15 vs. 0.99) p = 0.013 z = -2.486.

CONCLUSIONS

Psychological consequences such as depression and reported PTSD are present during the COVID-19 pandemic causing an impact particularly in individuals with allergic diseases. If we acknowledge the impact and how it is affecting our patients, we are able to implement interventions, follow up, and contribute to their overall well-being.

Psychosocial stress and ovarian function in adolescent and young adult cancer survivors

STUDY QUESTION

Is psychosocial stress associated with ovarian function in reproductive-aged survivors of cancer diagnosed as adolescents and young adults (AYA survivors)?

SUMMARY ANSWER

We observed no association between self-reported and biomarkers of psychosocial stress and ovarian function in AYA survivors.

WHAT IS KNOWN ALREADY

Psychosocial stress suppresses hypothalamic-pituitary-ovarian axis, resulting in ovulatory dysfunction, decreased sex steroidogenesis and lower fertility in reproductive-aged women. Many cancer survivors experience high psychosocial stress and hypothalamic-pituitary-adrenal axis dysregulation. The menstrual pattern disturbances and infertility they experience have been attributed to ovarian follicle destruction, but the contribution of psychosocial stress to these phenotypes is unknown.

STUDY DESIGN, SIZE, DURATION

A cross-sectional study was conducted estimating the association between perceived stress, measured by self-report and saliva cortisol, and ovarian function, measured by bleeding pattern, dried blood spot (DBS) FSH and LH, and saliva estradiol. We included 377 AYA survivor participants.

PARTICIPANTS/MATERIALS, SETTING, METHODS

AYA survivor participants were ages 15-35 at cancer diagnosis and ages 18-40 at study enrollment, had completed primary cancer treatment, had a uterus and at least one ovary, did not have uncontrolled endocrinopathy and were not on hormone therapy. Recruited from cancer registries, physician referrals and cancer advocacy groups, participants provided self-reported information on psychosocial stress (Perceived Stress Scale-10 (PSS-10)) and on cancer and reproductive (fertility, contraception, menstrual pattern) characteristics. DBS samples were collected timed to the early follicular phase (cycle Days 3-7) for menstruating individuals and on a random day for amenorrheic individuals; saliva samples were collected three time points within 1 day. FSH and LH were measured by DBS ELISAs, cortisol was measured by ELISA and estradiol was measured by liquid chromatography tandem mass spectrometry.

MAIN RESULTS AND THE ROLE OF CHANCE

The median age of participants was 34.0 years (range 19-41) at a median of 6.0 years since cancer diagnosis. The most common cancer was breast (32.1%). Median PSS-10 score was 15 (range 0-36), with 5.3% scoring ≥26, the cut point suggestive of severe stress. Cortisol levels followed a diurnal pattern and cortisol AUC was negatively correlated with PSS-10 scores (P = 0.03). Neither PSS-10 scores nor cortisol AUC were associated with FSH, LH, estradiol levels or menstrual pattern. Waking and evening cortisol and the cortisol awakening response also were not related to ovarian function measures.

LIMITATIONS, REASONS FOR CAUTION

Our analysis is limited by its cross-sectional nature, heterogeneity of cancer diagnosis and treatments and low prevalence of severe stress.

WIDER IMPLICATIONS OF THE FINDINGS

The lack of association between psychosocial stress and a variety of ovarian function measures in female AYA cancer survivors suggests that psychosocial stress does not have a significant impact on the reproductive axis of AYA survivors. This finding is important in counseling this population on their menstrual pattern and family building plans.

STUDY FUNDING/COMPETING INTEREST(S)

NIH HD080952, South Korea Health Industry Development Institute HI18C1837 (JK). Dr A.D. works for Bluebird Bio, Inc., Dr D.Z. works for ZRT Labs and Dr P.M.S. works for Ansh Labs, which did not sponsor, support or have oversight of this research. Other authors report no competing interests.

TRIAL REGISTRATION NUMBER

N/A.