Stress Hormone Concentrations Research Articles

Association between parental well-being and preschooler stress measured as hair cortisol concentration: A prospective cohort study.

Hair cortisol concentration (HCC) is a valuable biomarker for evaluating chronic stress in preschoolers. However, few studies have explored early life HCC and its associated factors. This prospective cohort study analysed the HCC in children aged 6-48months and its associations with parental HCC as well as positive and negative parental mental health outcomes. We used data from the ongoing Longitudinal Examination Across Prenatal and Postpartum Health in Taiwan (LEAPP-HIT) project, conducted in Taipei between 2020 and 2024. Hair samples were collected from both parents and children in 177 families (91 samples obtained during pregnancy and 86 during the postpartum period). The parents also completed self-reported questionnaires. Multiple linear regression was conducted to analyse the data. We observed a significant positive correlation between parents' and preschoolers' HCC. Furthermore, maternal depression (adjusted beta coefficient [aβ]=0.09, 95% confidence interval [CI]=0.02, 0.16) and perceived stress (aβ=0.15, 95% CI=0.02, 0.26) were positively associated with preschoolers' HCC. By contrast, higher maternal eudaimonia was associated with lower HCC in preschoolers (aβ=-0.11, 95% CI=-0.20, -0.01). For parents, maternal depression, anxiety, and perceived stress were independently associated with an increased HCC during the postnatal period, whereas maternal eudaimonia was negatively associated with HCC. Our results indicate that both mothers and fathers affect children's responses to stress. Assessment of cortisol stress hormone concentrations through hair samples can be a key means of detecting preschoolers' stress levels and enabling early intervention.

The possibly role of GnIH in stress and gut dysfunction in chicken

Stress is known to disrupt the intestinal barrier and induce intestinal dysfunction. A critical role for gonadotropin inhibitory hormone (GnIH) in stress has emerged. However, whether GnIH mediates stress-induced intestinal dysfunction remains unknown. The present study explored this question through in vivo and in vitro experiments in hens. Our in vivo experiments showed that continuous intraperitoneal injection of GnIH not only significantly increased the concentration of stress hormones in serum, but also significantly elevated the mRNA expression of glucocorticoid receptor (GR) in the duodenum and jejunum. Moreover, morphological and molecular analyses revealed that GnIH disrupted the physical and chemical barriers of the intestine and dramatically increased inflammatory factor levels in the intestine and serum of hens. Interestingly, the microbiomics results showed that GnIH altered the structure and composition of the gut flora in the cecum, revealing an increased abundance of harmful intestinal bacteria such as Desulfovibrionaceae. Similar results were found in in vitro studies in which the GnIH-induced intestinal mucosal barrier was disrupted, and inflammation increased in jejunal explants, although no significant difference was found in the expression of GR between the control and GnIH groups. Our results demonstrated that GnIH not only directly damaged intestinal barriers and elevated intestinal inflammation but also mediated stress and microflora imbalance-induced intestinal function disorder, suggesting that GnIH is a potential therapeutic target for gut dysfunction, stress-induced intestinal function disorder, and inflammatory bowel disease in animals and humans.

Miniaturized implantable temperature sensors for the long-term monitoring of chronic intestinal inflammation.

Diagnosing and monitoring inflammatory bowel diseases, such as Crohn's disease, involves the use of endoscopic imaging, biopsies and serology. These infrequent tests cannot, however, identify sudden onsets and severe flare-ups to facilitate early intervention. Hence, about 70% of patients with Crohn's disease require surgical intestinal resections in their lifetime. Here we report wireless, miniaturized and implantable temperature sensors for the real-time chronic monitoring of disease progression, which we tested for nearly 4 months in a mouse model of Crohn's-disease-like ileitis. Local measurements of intestinal temperature via intraperitoneally implanted sensors held in place against abdominal muscular tissue via two sutures showed the development of ultradian rhythms at approximately 5 weeks before the visual emergence of inflammatory skip lesions. The ultradian rhythms showed correlations with variations in the concentrations of stress hormones and inflammatory cytokines in blood. Decreasing average temperatures over the span of approximately 23 weeks were accompanied by an increasing percentage of inflammatory species in ileal lesions. These miniaturized temperature sensors may aid the early treatment of inflammatory bowel diseases upon the detection of episodic flare-ups.

Клінічне дослідження ефективності гідрогелевих пов’язок із лідокаїном у зменшенні запалення епізіотомної рани, післяпологового стресу та болю

Episiotomy, like other surgical interventions, triggers inflammatory responses within the physiological context by engaging proinflammatory mediators such as interleukins, cytokines, and prostaglandins. The painful experiences associated with episiotomy have the potential to significantly impact both the physical and emotional well-being of the parturient, particularly when considering individual variables such as the extent of the incision and the presence of complicating factors. In the postpartum period, the presence of fear, anxiety, and anticipation of pain may contribute to heightened stress levels, thereby exerting a profound impact on the emotional state of the parturient. Emotional stress, in turn, has the capacity to modulate pain perception, amplifying the discomfort associated with the incision. Elevated concentrations of stress hormones can influence immune responsiveness and inflammatory cascades, subsequently affecting the intricate process of episiotomy healing. Purpose - to examine determinants influencing the recovery of episiotomy wounds, encompassing inflammation markers, postpartum pain, and psychosocial stress. Materials and methods. A prospective randomized study analyzed clinical, laboratory, and historical data from 123 primiparous patients with episiotomy wounds at Kyiv City Maternity Hospital No. 5 during 2021-2022. The study comprised a comparison group (63 patients receiving standard treatment) and a research group (60 patients additionally utilizing hydrogel dressings with lidocaine). Both groups underwent assessment for heat shock protein Hsp60 and bacterial homolog GroEl levels, serum interleukin-6 dynamics, cortisol levels, pain, and stress levels according to the Edinburgh Postnatal Depression Scale. Statistical analysis employed the Mann-Whitney U test and EZR v. 1.54 statistical package. Results. No statistically significant differences were found in Hsp60 and GroEl levels, interleukin-6, cortisol, and pain levels after 24 hours between the comparison and research groups (p>0.05). However, interleukin-6 levels after 72 hours postpartum were 12.35 pg/ml (10.478-14.09) vs. 6.9 pg/ml (4.50-9.85); p<0.001; cortisol levels - 25.22 μg/dl (23.113-29.335) vs. 23.5 μg/dl (19.6-26.0), respectively; p<0.001. Pain levels by the visual analog scale after 72 hours postpartum were 4 (3-5) points vs. 3 (3-4) points; p<0.001; and at 10 days postpartum - 3 (2-3) points vs. 2 (2-3) points; p=0.010. Stress levels after 72 hours postpartum were 16 (13-19.75) points vs. 11.5 (9-15.5) points; p<0.001. Conclusions. Grasping the intricate interplay of episiotomy, inflammation markers, stress, and pain is pivotal for delivering comprehensive postpartum care. The implementation of evidence-based strategies, such as personalized pain management protocols, psychological support, and systematic monitoring of inflammation markers, can significantly enhance women's well-being and render the postpartum recovery process more comfortable. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

132 Genetics of Stress Hormone Concentrations in Hair of Healthy Nursery Pigs and Their Relationship with Back Test Responses

Abstract Cortisol and dehydroepiandrosterone (DHEA) are circulating adrenal hormones whose concentration in the blood varies in the face of infectious and non-infectious stressors. Their incorporation into hair makes their concentration in hair a robust retrospective assessment of HPA-axis activity as a measure of the stress response of an animal over the period of hair growth. Our objective was to estimate the genetic parameters of hormone concentrations in the hair of healthy pigs and their genetic correlation with responses to the standard back-test. Hair shaved from the rump area of 871 Large White X Landrace barrows (~40 d of age) from 6 breeding companies, maintained in a high-health nursery, was analyzed for cortisol and DHEA concentrations. Behavioral responses to a 60 s standard back-test were obtained at ~26 d of age, including the number of vocalizations (VN) and struggles (SN) and the intensity of the vocalizations (VI) and struggles (SI). All pigs were genotyped with a 50K SNP panel and imputed up to 650K. Estimates of heritability of log-transformed levels of cortisol and DHEA using univariate animal models were 0.26 ± 0.08 and 0.00, respectively, while litter effects explained 0.19 ± 0.05 and 0.09 ± 0.04 of the phenotypic variance, respectively. Back-test responses were more heritable, ranging from 0.34 ± 0.08 (VI) to 0.58 ± 0.08 (VN), with small litter effects (0.00 to 0.06). Estimates of genetic correlations using bivariate animal models were high among the back-test responses, ranging from 0.58 ± 0.16 for SN-VN to 0.96 ± 0.04 for VN-VI and 0.99 ± 0.10 for SN-SI. Estimates of genetic correlations of cortisol with back-test responses ranged from low (0.08 ± 0.23 with SI) to moderate (0.66 ± 0.27 with SN). We conclude that the concentration of cortisol in the hair of healthy nursery pigs is a heritable molecular phenotype and is genetically correlated with responses to the back-test. In subsequent research, their potential as indicator traits to select for disease resilience will be investigated. This study was funded by Genome Canada, PigGen Canada, and USDA-NIFA grant # 2021-67015-34562.

STUDY OF STRESS-PROTECTIVE AND ANXIOLYTIC ACTIONS OF SCUTELLARIA BAICALENSIS GEORGI EXTRACT UNDER "SOCIAL" STRESS

Background. The search for natural adaptogens is promising due to the possibility of expanding the range of drugs that contribute to the adaptation of the body to adverse environmental factors.
 Purpose. To study the stress-protective and anxiolytic action of the extract of Scutellaria baicalensis Georgi under conditions of "social" stress.
 Materials and methods. We used an extract of Scutellaria baicalensis Georgi. The study of the stress-protective and anxiolytic effects of the extract was carried out on 84 male non-linear rats aged 7-9 months. The first stage of the experiment involved the study of pharmacological actions in the absence of stress, and at the second stage, under conditions of “social” stress, the expected effects were determined on animals, in the groups of which individuals of dominant and submissive types of behavior were identified. Determination of the content of corticosterone, adrenaline and noradrenaline (nmol/l) was carried out by enzyme immunoassay.
 Results. It was established that in the norm, the experimental groups that received the extract of Scutellaria baicalensis Georgi, medicinal products "Mebikar®" and "Phezam®" showed a significant decrease in the level of corticosterone compared with the control group. At the second stage of the study in groups when modeling "social" stress, it was found that there were significant differences between the concentration of stress hormones in animals of dominant and submissive types. Administration of Scutellaria baicalensis Georgi extract reduced hormone levels for both aggressors and victims relative to the stressed control group. We observed a decrease in the concentration of corticosterone by 1.5 and 1.5 (p<0.05) times, the level of adrenaline by 3.2 and 3.1 (p<0.05) times, the content of norepinephrine by 1.6 and 1.6 (p<0.05) times for individuals of dominant and submissive types, respectively. The presence of the leveling effect of the Scutellaria baicalensis Georgi extract proves its anxiolytic and stress-protective effect.
 Conclusion. Scutellaria baicalensis Georgi extract at a dose of 100 mg/kg/day, when exposed to "social" stress, has a stress-protective and anxiolytic effect, reducing the severity of stress-induced changes, limiting hyperactivation of the central stress-realizing systems, correcting the endogenous antioxidant system of the body.

EEG-derived pain threshold index-guided versus standard care during propofol-remifentanil anesthesia: A randomized controlled trial

PurposeThe pain threshold index (PTI), a novel index of nociception based on spontaneous EEG wavelet analysis, has been reported to provide reliable accuracy for predicting postoperative pain and hemodynamic reactivity. The present study is aimed to investigate whether PTI-guided analgesia reduces the pain intensity and rate of remedial analgesia in the post-anesthesia care unit (PACU). MethodsA total of 122 females undergoing elective gynecologic surgeries had been randomized to receive either PTI-guided analgesia (PTI group) or standard clinical care (control group). Remifentanil administration in the PTI group was guided by PTI to maintain the value between 40 and 65, while that in the control group was guided by hemodynamic changes. The primary outcome was remedial analgesia rate in the PACU. The postoperative pain scores, intraoperative remifentanil requirements, opioid-related adverse events and perioperative serum stress hormone concentrations between the two groups were also compared. FindingsIt was found that 23 of 58 patients (40%) in the control group and 8 of 58 patients (14%) in the PTI group needed remedial analgesia. The relative risk of receiving remedial analgesia was 2.88 (95% CI, 1.40–5.89, P = 0.002) in the control group. Sufentanil consumption in the PACU (μg) was lower in the PTI group (P = 0.002) than in the control group. Remifentanil and propofol consumption, opioid-related adverse events between these two groups were comparable. ImplicationsPTI-guided analgesia during gynaecologic operations resulted in 25.87% less remedial analgesia. However, studies with different PTI thresholds and larger, more diverse populations should be conducted to further demonstrate the clinical effectiveness of PTI.

Effects of more natural housing conditions on the muscular and skeletal characteristics of female C57BL/6J mice

BackgroundEnrichment of home cages in laboratory experiments offers clear advantages, but has been criticized in some respects. First, there is a lack of definition, which makes methodological uniformity difficult. Second, there is concern that the enrichment of home cages may increase the variance of results in experiments. Here, the influence of more natural housing conditions on physiological parameters of female C57BL/6J mice was investigated from an animal welfare point of view. For this purpose, the animals were kept in three different housing conditions: conventional cage housing, enriched housing and the semi naturalistic environment. The focus was on musculoskeletal changes after long-term environmental enrichment.ResultsThe housing conditions had a long-term effect on the body weight of the test animals. The more complex and natural the home cage, the heavier the animals. This was associated with increased adipose deposits in the animals. There were no significant changes in muscle and bone characteristics except for single clues (femur diameter, bone resorption marker CTX-1). Additionally, the animals in the semi naturalistic environment (SNE) were found to have the fewest bone anomalies. Housing in the SNE appears to have the least effect on stress hormone concentrations. The lowest oxygen uptake was observed in enriched cage housing.ConclusionsDespite increasing values, observed body weights were in the normal and strain-typical range. Overall, musculoskeletal parameters were slightly improved and age-related effects appear to have been attenuated. The variances in the results were not increased by more natural housing. This confirms the suitability of the applied housing conditions to ensure and increase animal welfare in laboratory experiments.

Stress response as a contributing factor in horses with laminitis.

Laminitis is a complex and debilitating disease of horses. Numerous predisposing factors contribute to laminitis development, however the exact pathogenesis remains undetermined. Serum T4, cortisol, and histamine are components of the innate stress response and could play a causative or contributory role. Stress hormone concentrations in laminitis are largely unknown. To evaluate parameters associated with stress response in horses with laminitis, and compare these to healthy horses and horses with gastrointestinal (GI) disease. Thirty-eight adult horses presenting for non-medical conditions, GI abnormalities, or clinical laminitis were prospectively enrolled. Horses were assigned to the appropriate disease group (healthy, GI disease, and laminitis) and had blood drawn on presentation to the hospital. Samples were analyzed for plasma endogenous adrenocorticotrophic hormone (eACTH), serum cortisol, serum thyroid hormone, and plasma histamine. Stress hormone concentrations were significantly different between horses in the laminitis and GI disease groups. Plasma histamine levels were highest in horses with laminitis, compared with GI disease and controls. Both horses with laminitis and GI disease had increased plasma eACTH when compared to healthy horses. Horses with GI disease had higher serum cortisol concentrations than horses with laminitis or controls. Serum T4 was lower in horses with GI disease than in horses with laminitis and controls. Horses with laminitis had relative increases in both plasma histamine and eACTH concentrations. Serum T4 and cortisol concentrations of horses with laminitis did not differ significantly when compared to healthy horses. The role of stress hormones in equine disease warrants further investigation.

Loss of behavioral stress response in blind cavefish reduces energy expenditure.

The stress response is essential for animal self-defense and survival. However, species may exhibit stress response variation depending on their specific environmental and selection pressures. Blind cavefish dwell in cave environments, which differ markedly in stressors and resource availability compared to surface aquatic environments. However, whether blind cavefish exhibit differences in stress response as an adaptation to their cave environments remains unclear. Here, we investigated differences in stress response in six closely related Triplophysa species, including three blind cavefish (T. longibarbata, T. jiarongensis, and T. rosa) and three normal-sighted river fish (T. nasobarbatula, T. dongsaiensis, and T. bleekeri). Results showed that blind cavefish exhibited a range of distinct behavioral responses compared to sighted river fish, including greater levels of activity, shorter duration of freezing, absence of erratic movements or thrashing behavior, and opposite behavioral trends over time. Furthermore, the cavefish species demonstrated attenuated increases in metabolic rate in response to stressors related to novel environments. Cave-dwelling T. rosa also exhibited lower basal hypothalamic-pituitary-inter-renal (HPI) axis-related gene expression levels and stress hormone concentrations compared to river-dwelling T. bleekeri. These results suggest that blind cavefish may have lost their behavioral stress response, potentially mediated by a reduction in basal activity of the HPI axis, thus enabling the conservation of energy by reducing unnecessary expenditure in energy-limited caves.

A Pilot Study Evaluating the Feasibility of Testing for an Acute Impact of Human Exposure to a Power-line Frequency Magnetic Field on Blood Cortisol and Thyroid-Stimulating Hormone.

Numerous studies have been carried out on the potential effects of an extremely low frequency (ELF-0-300 Hz) magnetic field (MF) on human health. However, there is limited data on the effect of a high exposure level to ELF MFs for a prolonged period. Therefore, the objective of this pilot work was to demonstrate the feasibility of a study evaluating the stress hormone concentrations resulting from a 10-min exposure to a 60 Hz MF of several tens of thousands of µT. In this pilot study, human volunteers were thus exposed for the first time to a 60 Hz, 50 mT MF for a duration of 10 min. Stress hormone levels were measured before (once), during (twice) and after (once) this 10-min exposure period. The small sample size (n = 5) did not allow to conduct standard inferential statistical tests and no conclusion regarding the exposure effects can be drawn. However, this study demonstrates the feasibility of using a simple blood testing material in a protocol testing for the effect of a 10-min exposure to a high MF level in healthy human volunteers. © 2022 Bioelectromagnetics Society.

Stress Hormones Cortisol and Aldosterone, and Selected Markers of Oxidative Stress in Response to Long-Term Supplementation with Omega-3 Fatty Acids in Adolescent Children with Depression.

Late childhood and adolescence are crucial periods of brain development with high vulnerability to environmental insults. The aim of this study was to test the hypotheses that in adolescents with depression (a) 12 weeks-supplementation with omega-3 fatty acids results in the attenuation of salivary stress hormone concentrations; (b) the mentioned supplementation improves potentially disrupted daily rhythm of stress hormones; (c) stress hormone concentrations correlate with values of selected markers of oxidative stress. The sample consisted of 60 patients suffering from depression aged 11–18 years. Hormone concentrations in saliva were measured in the morning and midday before (baseline) and after (6, 12 weeks) food supplementation with omega-3 or omega-6 (as comparator) fatty acids. Morning cortisol decreased in response to omega-3 but not omega-6 fatty acids at 12 weeks compared to baseline. No changes were observed in aldosterone concentrations. The obtained results show that adolescent children with depression preserved the daily rhythm of both stress hormones. Baseline morning cortisol concentrations correlated positively with depression severity and lipoperoxides, and negatively with docosahexaenoic acid. Aldosterone concentrations correlated positively with 8-isoprostane. Thus, both hormones showed positive correlation with the selected markers of oxidative stress suggesting that enhanced stress hormone secretion may be associated with increased oxidative tissue damage in adolescent children with depression. This study was registered with the ISRCTN registry (DEPOXIN study, ISRCTN81655012).

Chronic treatment with enhancer drugs modifies the gene expression of selected parameters related to brain plasticity in rats under stress conditions

Selegiline, also known as L-deprenyl, and (2R)-1-(1-benzofuran-2-yl)-N-propylpentane-2-amine (BPAP) were found to induce enhancement of monoamine neurotransmission in low and very low doses. In addition, these enhancers may modify glutamatergic neurotransmission. The aim of the present study was to test the hypothesis that under stress conditions, chronic treatment with enhancer drugs has a positive impact on the glutamatergic system and other parameters related to brain plasticity, stress-related systems, and anxiety behavior. We exposed male Wistar rats to a chronic mild stress procedure combined with chronic treatment with two synthetic enhancer drugs. The gene expression of GluR1, an AMPA receptor subunit was reduced by repeated treatment with deprenyl in the hippocampus and with both BPAP and deprenyl in the prefrontal cortex. A significant reduction of NMDA receptor subunit GluN2B expression was observed in the hippocampus but not in the prefrontal cortex. Deprenyl treatment led to an enhancement of hippocampal BDNFmRNA concentrations in stress-exposed rats. Treatment with enhancer drugs failed to induce significant changes in stress hormone concentrations or anxiety behavior. In conclusion, the present study in chronically stressed rats showed that concomitant treatment with enhancer drugs did not provoke substantial neuroendocrine changes, but modified gene expression of selected parameters associated with brain plasticity. Observed changes may indicate a positive influence of enhancer drugs on brain plasticity, which is important for preventing negative consequences of chronic stress and enhancement of stress resilience. It may be suggested that the changes in glutamate receptor subunits induced by enhancer drugs are brain region-specific and not dose-related.

Testosterone but not cortisol concentrations in hair correlate between mothers and their prepubertal children under real-life stress conditions

The aim of the present study is to test the hypothesis that there is an association between the neuroendocrine state, reflected by testosterone and cortisol concentrations in hair, of the mother and her child under difficult real-life stress conditions (COVID-19 pandemic). The research sample consisted of 45 healthy mothers and their prepubertal children (7 – 11 years) of both sexes. The hair samples of mother-child dyads were collected twice to obtain cumulative stress hormone concentrations from April till the end of June and July till the end of September 2020. Thus, 90 mother-child pairs were analyzed. The results showed that both cortisol and testosterone concentrations were significantly higher in the hair of mothers compared to those in their children. The results of cortisol concentrations in hair do not support the hypothesis stated above. In line with our hypothesis are the results of hair testosterone measurements showing a positive correlation between testosterone concentrations in mothers and their children. With respect to the known relationship of testosterone with aggressive behavior, an important finding is that above-mentioned correlation was particularly strong in women with intense subjective feelings of anger in the investigated three months period. Women with strongly prevalent subjective feelings of sadness failed to show a significant correlation between hair cortisol concentrations in mothers and their children, in spite of the known relationship of cortisol to depressive mood. It may be suggested that chronic testosterone secretion reflects the association between the neuroendocrine function of the mother and her child under real-life stress conditions.

Acute stress effects of impulsive noise during mental work

Impulsive sound has been found to annoy people more than steady-state sound or many other types of sound presented at the same sound level. This study examined the physiological, performance, and subjective effects of impulsive sound on working humans. Exposure to impulsive sound (65 dB LAeq) was compared with quiet sound (35 dB LAeq) and steady-state sound (65 dB LAeq). This parallel-group study, where each participant was exposed to one sound condition, had altogether 59 participants. Physiological stress was measured with stress hormone concentrations in plasma (cortisol and noradrenaline), heart rate variability (HRV), and blood pressure. Psychological stress was measured with subjective noise annoyance, workload, and fatigue. Performance was measured in tasks requiring constant concentration (visual and auditory serial recall and N-back). Compared to quiet sound, impulsive sound caused more annoyance, workload, and lack of energy, raised cortisol concentrations, reduced systolic blood pressure, and decreased accuracy in the 3-back task. Compared with steady-state sound, impulsive sound was experienced as more annoying and causing a higher workload and more lack of energy. Impulsive sound caused physiological and psychological stress and decreased performance compared to quiet sound. Part of this load was due to the increased sound level, which was evident as a physiological stress reaction. Still, there was also an extra stress effect related to the impulsiveness of the sound, reflected as a psychological experience. Special care should be paid to impulsive sound, especially in environments where people are performing mental work.

A review of the effects of acute and chronic cannabinoid exposure on the stress response

While cannabis has been used for centuries for its stress-alleviating properties, the effects of acute and chronic cannabinoid exposure on responses to stress remain poorly understood. This review provides an overview of studies that measured stress-related endpoints following acute or chronic cannabinoid exposure in humans and animals. Acute cannabinoid exposure increases basal concentrations of stress hormones in rodents and humans and has dose-dependent effects on stress reactivity in humans and anxiety-like behavior in rodents. Chronic cannabis exposure is associated with dampened stress reactivity, a blunted cortisol awakening response (CAR), and flattened diurnal cortisol slope in humans. Sex differences in these effects remain underexamined, with limited evidence for sex differences in effects of cannabinoids on stress reactivity in rodents. Future research is needed to better understand sex differences in the effects of cannabis on the stress response, as well as downstream impacts on mental health and stress-related disorders.

Adaptation to coastal soils through pleiotropic boosting of ion and stress hormone concentrations in wild Arabidopsis thaliana.

Local adaptation in coastal areas is driven chiefly by tolerance to salinity stress. To survive high salinity, plants have evolved mechanisms to specifically tolerate sodium. However, the pathways that mediate adaptive changes in these conditions reach well beyond Na+ . Here we perform a high-resolution genetic, ionomic, and functional study of the natural variation in Molybdenum transporter 1 (MOT1) associated with coastal Arabidopsis thaliana accessions. We quantify the fitness benefits of a specific deletion-harbouring allele (MOT1DEL ) present in coastal habitats that is associated with lower transcript expression and molybdenum accumulation. Analysis of the leaf ionome revealed that MOT1DEL plants accumulate more copper (Cu) and less sodium (Na+ ) than plants with the noncoastal MOT1 allele, revealing a complex interdependence in homeostasis of these three elements. Our results indicate that under salinity stress, reduced MOT1 function limits leaf Na+ accumulation through abscisic acid (ABA) signalling. Enhanced ABA biosynthesis requires Cu. This demand is met in Cu deficient coastal soils through MOT1DEL increasing the expression of SPL7 and the copper transport protein COPT6. MOT1DEL is able to deliver a pleiotropic suite of phenotypes that enhance salinity tolerance in coastal soils deficient in Cu. This is achieved by inducing ABA biosynthesis and promoting reduced uptake or better compartmentalization of Na+ , leading to coastal adaptation.

The Effects of Furosemide on Behavioral and Hormonal Parameters in Male and Female Mice Subjected to Immobilization and Cold-Water Stress.

IntroductionThe diuretic agent furosemide (FUR, 25 and 50 mg/kg) has been shown in a single report to act as an anti-stressor agent in two models of acute stress in mice, viz. electric foot–shock stress and immobilization (IMS). The present work aimed to investigate the possible anti-stressor action of FUR on two models of acute stress in mice, cold-water stress (CWS) and IMS, and tried to determine whether gender has any impact on the effect of FUR.MethodsFUR (40 mg/kg) was injected intraperitoneally, and after 30 minutes, mice were subjected to CWS (4°C for three minutes) or IMS (fixing movement for two and a half hrs using adhesive tape). Motor and exploratory activities, neuromuscular coordination, and thermal nociception were then tested. Blood was collected from the mice and used to measure the concentrations of three stress hormones (corticosterone, epinephrine and prolactin).ResultsMice subjected to CWS and IMS had significantly reduced motor and exploratory activities, neuromuscular coordination, and increased nociception. CWS and IMS also significantly increased the plasma concentrations of the three hormones. FUR pretreatment significantly mitigated these stress-induced hormonal changes. There was no significant sex difference when CWS or IMS was applied.DiscussionIMS and CWS stimuli in male and female mice caused significant elevations in the plasma concentrations of corticosterone, epinephrine, and prolactin, accompanied by a significant reduction of motor and exploratory activities, neuromuscular coordination, and thermal nociception. There were no sex differences when IMS was applied. In stressed mice, prior administration of FUR (40 mg/kg) significantly decreased the concentrations of stress hormones, and this effect significantly mitigated the stress-induced behavioural and motor changes.

The influence of acclimatization on stress hormone concentration in serum during heat stress.

This study was aimed to examine the influence of acclimatization on the change of concentration of stress hormones in men's serum exposed to heat stress during physical training. The study included a total of 40 men, aged 19-21years, divided randomly into four groups: CTRL group: control, exposed to the Exercise Tolerance Testing in comfortable conditions; O group: exposed to Exercise Tolerance Testing in a warm environment; P group: exposed to passive acclimation to heat for 10days, followed by Exercise Tolerance Testing in a warm environment; A group: exposed to active acclimation to heat for 10days, followed by Exercise Tolerance Testing in a warm environment. All participants were tested for thermoregulation and acclimatization, skin and tympanic temperature, heart rate (HR), hormonal status and sweating. The mean skin temperature was the lowest in the control group of subjects exposed to physical exertion under comfortable conditions, and at each point of measurement it was statistically significantly different from that of the other study groups (p < 0.001). Sweating intensity was statistically significantly the lowest in the CTRL group (0.32 ± 0.04l/m2/h; p < 0.001), compared to all other groups. Cortisol was significantly altered in O group (632.2 ± 92.3; 467.2 ± 89.7), testosterone levels were significantly altered in P (19.2 ± 9.3; 16.4 ± 7.3) and in A groups (22.1 ± 12.4; 14.9 ± 9.9), while prolactin was changed in O (392.1 ± 51.3; 181.4 ± 42.3), P (595.1 ± 191.1; 191.2 ± 52.5), and A group (407.4 ± 189.3; 173.4 ± 43.9) after the experimental period. The impact of acclimatization on hormonal indicators emphasizes its importance in the response of the endocrine system of soldiers to perform military activities in warm climates.

Effect of high-fidelity simulation on alpha-amylase activity and concentrations of secretory immunoglobulin class A, cortisol, and testosterone among medical students

PurposeHigh-fidelity simulation calls heavily upon cognitive capacities and generates stress and anxiety. The objective of this prospective, observational study was to evaluate the degree of stress in medical students by measuring hormone levels during critical care classes.MethodsOverall, 55 students (senior years of medical faculty) of both sexes were divided into 5-person teams. Demographic data and information on diagnosed diseases, stimulants used, and previous experience in the field of medical simulation were collected with a personal questionnaire. Before starting the scenario (T0), after the end of the scenario (T1), and 120 min thereafter (T2), stress level was measured. For this purpose, systolic blood pressure, diastolic blood pressure, mean blood pressure, heart rate and blood oxygen saturation were evaluated. In addition, saliva was collected to determine alpha-amylase activity and the concentrations of secretory immunoglobulin class A, cortisol, and testosterone.ResultsAmong hemodynamic parameters, systolic and mean blood pressure and heart rate were significantly higher in T1 than in T0 and T2 time points (p < 0.05). Cortisol concentration was higher at T2 compared with T0 and T1. Alpha-amylase activity was highest at T1. Secretory immunoglobulin class A concentration was highest at T0, followed by T1 and then T2. These differences were not statistically significant. Testosterone concentration showed significantly higher values at T2 compared with T0 and T1 (p < 0.05). The analysis of team leaders vs. other members revealed significantly lower cortisol and alpha-amylase values in leaders (p < 0.05).ConclusionsHigh-fidelity simulation is a useful education method in medical subjects, especially in cases where a mistake could produce serious or irreversible consequences. It can increase stress hormone concentrations and thus can be assumed effective as a learning aid even in senior-year students of medical faculty.