Urine cortisol concentration as a biomarker of stress is unrelated to IVF outcomes in women and men

Fur Cortisol in French Bulldogs with Different Manifestations of Brachycephalic Obstructive Airway Syndrome

In the present study, 33 French bulldogs with varying degrees of brachycephalic obstructive airway syndrome (BOAS) were evaluated for various parameters to provide evidence of chronic stress in the dogs. For this purpose, an owner interview, a clinical examination, and cortisol concentrations in the fur of the dogs were collected. The median cortisol concentration in the fur of the dogs suffering from BOAS (n = 19) was 0.99 pg/mg (range 0.63-66.18), while that of the control group (n = 14) was 1.13 pg/mg (range 0.3-43.45). However, the statistical analysis did not reveal a statistically significant difference; therefore, it is not possible to distinguish between dogs clinically affected with BOAS and those without clinically relevant signs of the disease. There was no statistically significant difference between the age of the animals and the fur cortisol. None of the owners in the examination and control groups indicated that their dog was suffering from chronic stress which shows that the disease is easily underestimated and remains common. Thus, a thorough clinical examination by an experienced veterinarian remains the gold standard in order to diagnose BOAS.

Lead exposure, glucocorticoids, and physiological stress across the life course: A systematic review

The biological pathways linking lead exposure to adverse outcomes are beginning to be understood. Rodent models suggest lead exposure induces dysfunction within the hypothalamic-pituitary-adrenal (HPA) axis and glucocorticoid regulation, a primary physiological stress response system. Over time, HPA axis and glucocorticoid dysfunction has been associated with adverse neurocognitive and cardiometabolic health, much like lead exposure. This systematic review utilized PRISMA guidelines to synthesize the literature regarding associations between lead exposure and downstream effector hormones of the HPA axis, including cortisol, a glucocorticoid, and dehydroepiandrosterone (DHEA), a glucocorticoid antagonist. We additionally determined the state of the evidence regarding lead exposure and allostatic load, a measure of cumulative body burden resultant of HPA axis and glucocorticoid dysfunction. A total of 18 articles were included in the review: 16 assessed cortisol or DHEA and 3 assessed allostatic load. Generally, the few available child studies suggest a significant association between early life lead exposure and altered cortisol, potentially suggesting the impact of developmental exposure. In adulthood, only cross sectional studies were available. These reported significant associations between lead and reduced cortisol awakening response and increased cortisol reactivity, but few associations with fasting serum cortisol. Two studies reported significant associations between increasing lead exposure and allostatic load in adults and another between early life lead exposure and adolescent allostatic load. The paucity of studies examining associations between lead exposure and allostatic load or DHEA and overall heterogeneity of allostatic load measurements limit conclusions. However, these findings cautiously suggest associations between lead and dysregulation of physiological stress pathways (i.e., glucocorticoids) as seen through cortisol measurement in children and adults. Future research would help to elucidate these associations and could further examine the physiological stress pathway as a mediator between lead exposure and detrimental health outcomes.

Effects of cadmium and lead co-exposure on glucocorticoid levels in rural residents of northwest China

Cadmium (Cd) and lead (Pb) are important environmental endocrine disruptors that are associated with adverse health problems. However, the effects of co-exposure to Cd and Pb on glucocorticoids (GCs) in the body at environmental levels are limited. A total of 468 subjects from the Dongdagou-Xinglong cohort (DDG-XL) were included in this study. We measured the serum levels of two representative endogenous GCs [cortisol (CRL) and cortisone (CRN)], and whole blood levels of Cd and Pb. Multiple linear regression models were constructed to explore the associations of single or combined Cd and Pb exposure with serum CRL and CRN levels. The interactive effects of Cd and Pb on GCs were further assessed using mediation analysis and moderation analysis. Single-heavy metal exposure analysis with adjustment for potential confounders showed that the serum CRL level decreased when the blood Cd or Pb concentration gradually increased (P trend <0.01). Additionally, subjects with high Cd or Pb exposure (Q4) had significantly reduced serum CRN levels compared to those with low Cd or Pb exposure (Q1) (P < 0.05). In Cd and Pb co-exposure analysis, significant negative dose-response relationships were observed between co-exposure to Cd and Pb and serum CRL and CRN levels. Furthermore, mediation analysis showed that Cd completely mediated the relationship between Pb and GCs, and moderation analysis suggested that Pb might weaken the negative relationship between Cd and GCs. These findings suggest that single or combined exposure to Cd and Pb interferes with the homeostasis of serum CRL and CRN levels. Furthermore, we innovatively propose that Cd and Pb may have interactive effects on GCs levels, and Pb can antagonize the negative relationship between Cd and GCs, which may provide clues for further studies on endocrine and metabolic disorders related to these heavy metals.

A Novel Electrochemical Aptasensor Based on a New Platform of Samarium Molybdate Flower-like Nanoparticles@Poly(pyrrole) for Non-Invasive Determination of Saliva CORTISOL

Cortisol, a famous stress biomarker, can be considered a potential predictor of cardiac diseases in humans. The presence of cortisol in saliva has encouraged researchers to design point-of-care devices for cortisol concentration in biological fluids. Here, human salivary cortisol was analyzed through a new non-invasive voltammetric aptasensor. Although cortisol is an electroactive compound, generally, the reduction in the current peak has been considered; however, this does not show a strong signal on a bare electrode surface, especially at low concentration levels. Hence, in this study, cortisol concentration was measured electrochemically and indirectly by monitoring the difference between electrochemical probe signals in the presence and absence of cortisol. A new polymeric nanocomposite of samarium molybdate flower-like nanoparticles decorated in poly(pyrrole) was electro-synthesized on the surface of a glassy carbon electrode. Then, reduced graphene oxide was cast on the surface. Finally, the cortisol aptamer was immobilized covalently on the reduced graphene oxide. This platform was used to increase the oxidation current peak of the ferricyanide solution as a probe as well as its electrocatalyst. The novel designed polymeric has the potential ability for effective immobilization of aptamers on the electrode surface without decreasing their biological activities. Additionally, it can enhance the probe electrochemical signal. The differential pulse voltammetric method (DPV) was applied as the detection technique. By optimizing the effective parameters, a determination range of 5.0 × 10⁻¹⁴–1.5 × 10⁻¹¹ mol/L and a limit of detection of 4.5 × 10⁻¹⁴ mol/L were obtained. Selectivity of the proposed aptasensor relative to β-estradiol, progesterone and also prednisolone was studied as well. Finally, cortisol in a healthy human saliva sample was successfully analyzed by the proposed biosensors.

Application of Salivary Biomarkers in the Diagnosis of Fibromyalgia

Fibromyalgia (FM) is a highly prevalent syndrome that impairs the quality of life of the patients; however, its diagnosis is complex and mainly centered on pain symptoms. The study of salivary biomarkers has proven highly useful for the diagnosis and prognosis of numerous diseases. The objective of this review was to gather published data on the utilization of salivary biomarkers to facilitate and complement the diagnosis of FM. Salivary biomarkers used in FM diagnosis include cortisol; calgranulin; and the enzymes α-amylase, transaldolase, and phosphoglycerate mutase. Increased serum levels of C-reactive protein, cytokines interleukin 1-β, interleukin 6, interleukin 8, interleukin 10, interleukin 17, tumor necrosis factor α, and various chemokines may serve as salivary biomarkers, given observations of their increased serum levels in patients with FM. Further research is warranted to study in depth the role and performance of biomarkers currently used in FM diagnosis/prognosis and to identify novel salivary biomarkers for this disease.

Stress in couples undergoing assisted reproductive technology

PURPOSE

To determine the associations between pre-treatment self-reported stress level, salivary cortisol levels, and clinical pregnancy outcome in couples undergoing assisted reproductive technology treatment (ART).

STUDY DESIGN

Seventy-five couples (150 patients) undergoing ART treatment were enrolled in this study. Psychological variables were assessed using the Perceived Stress Scale, Beck Anxiety Inventory, State-Trait Anxiety Inventory, and Beck Depression Inventory. Salivary cortisol levels were obtained from each couple prior to commencing gonadotropin treatment at several times (upon waking and at 15, 30, and 60 min after waking).

RESULTS

There was no statistically significant association between the self-reported stress levels and the ART treatment outcome in couples. Women with a successful outcome after ART treatment had higher median salivary cortisol levels than women who had an unsuccessful result [24.7 (19.9-63.1) vs. 20.7 (10.4-30.4), respectively]. There was no statistically significant difference in the median salivary cortisol levels of men in relation to ART treatment outcome. Salivary cortisol levels of the couples were not correlated.

CONCLUSIONS

Women who had higher median salivary cortisol levels in the pre-treatment period had a higher clinical pregnancy rate. This result suggests that moderately increased activity of the hypothalamic-pituitary-adrenal axis during ART treatment might be associated with successful conception.

Sex and dose-dependent responses of urinary and faecal glucocorticoid metabolite concentrations following an ACTH challenge in eastern rock sengis (Elephantulus myurus)

Non-invasive methods for measuring glucocorticoids and their metabolites are frequently used in ecological, behavioural and physiological studies of mammals. Using faeces, urine and other matrices for such a measurement has considerable advantages in comparison to more traditional methods, but also requires thorough validation of the methods used. Eastern rock sengis (Elephantulus myurus) are fascinating African mammals and the non-invasive monitoring of the adrenocortical activity opens up new opportunities to study their biology. We were able to validate two assays for measuring urinary (uGCM) and faecal glucocorticoid metabolite (fGCM) concentrations in this species using a dose-dependent challenge with adrenocorticotropic hormone (ACTH). A higher concentration of ACTH elicited higher uGCM and fGCM concentrations in both males and females. Interestingly, uGCM and fGCM concentrations and the responses to ACTH were higher in females than in males and small changes in faecal glucocorticoid metabolites could not be reliably detected in males. In contrast to ACTH, a saline injection did not result in an increase in uGCM or fGCM concentrations. The study also provided insight into when responses to a stressor are likely to be detected in the urine and faeces of sengis and opens up new opportunities to study the stress physiology of this and other sengi species. It further emphasises the importance of thoroughly validating non-invasive methods for measuring hormones in both sexes of a species and for incorporating dose-dependent approaches.

Melatonin Protects Rabbit Somatic Cell Nuclear Transfer (SCNT) Embryos from Electrofusion Damage

The study’s objectives were to examine the effects of electrofusion on rabbit somatic cell nuclear transfer (SCNT) embryos, and to test melatonin as a protective agent against electrofusion damage to SCNT embryos. The levels of reactive oxygen species (ROS), the epigenetic state (H3K9me3), and the content of endoplasmic reticulum (ER) stress-associated transcripts (IRE-1 and CHOP) were measured. Melatonin was added during the preimplantation development period. The total blastocyst cell numbers were counted, and the fragmentation rate and apoptotic index were determined and used to assess embryonic development. Electrofusion increased (1) ROS levels at the 1-, 2-, 4-, and 8-cell stages; (2) H3K9me3 levels at the 2-, 4-, and 8-cell stage; and (3) the expression of IRE-1 and CHOP at the 8-cell, 16-cell, morula, and blastocyst stages. The treatment of SCNT embryos with melatonin significantly reduced the level of ROS and H3K9me3, and the expression levels of IRE-1 and CHOP. This treatment also significantly reduced the fragmentation rate and apoptotic index of blastocysts and increased their total cell number. In conclusion, the electrofusion of rabbit SCNT embryos induced oxidative stress, disturbed the epigenetic state, and caused ER stress, while melatonin reduced this damage. Our findings are of signal importance for improving the efficiency of SCNT and for optimizing the application of electrical stimulation in other biomedical areas.

Quantitative profiling of cortisol metabolites in human urine by high-resolution accurate-mass MS

Aim, materials & methods: Urinary cortisol profile has the potential as a diagnostic biomarker. We therefore developed a stable-isotope dilution ultraperformance chromatography multistage MS-based method to quantify cortisol and 16 metabolites in human urines. Results & conclusion: The LOD for cortisol and its metabolites ranges from 0.02 to 5.81 pg/μl urine. The inter- and intraday variations were 3.7-12.9% and 3.5-15.6%, respectively. Among the metabolites analyzed, significant person-to-person heterogeneity was observed, demonstrating the need for comprehensive metabolite profiling in diagnosis. Nevertheless, the glucuronides of dihydrocortisol, dihydrocortisone, tetrahydrocortisol, allo-tetrahydrocortisol and tetrahydrocortisone are the major ones. The sum of the glucuronidated and free forms constitute >93% of the metabolites analyzed, which is termed as total cortisol equivalent. Total cortisol equivalent may serve as a surrogate of cortisol secretion. Clinical trial registration number: NCT02500472.

Impact of the Relationship of Stress and the Immune System in the Appearance of Alzheimer's Disease

The understanding of how the immune system works, as well as its relationship with the stress level, seems to be important at the start of the Alzheimer's disease (AD). To analyze this, immunoglobulin A (IgA) and cortisol in saliva were measured using ELISA in patients with mild AD and healthy volunteers, and the production of both biomarkers was compared and correlated. In participants without AD, IgA was higher when cortisol was lower, and the opposite happened in participants with AD, with the quantification in saliva being a suitable method to determine it.