Evaluation of the hypothalamic-pituitary-adrenal axis function in childhood and adolescence

Measuring Children's Stress via Saliva in Surgical and Endoscopic Procedures and Its Measurement Intention in the Community: Reality-Future Prospects

(1) Background: Children who undergo surgical or endoscopic procedures display high levels of stress, and various means are applied to reduce their anxiety. Salivary cortisol (S Cortisol) and salivary alpha-amylase (SAA) are often used as a valid biomarker of stress. The primary purpose of the study was the investigation of stress levels through S Cortisol and S amylase after intervention in surgical or endoscopic procedures (gastroscopy-colonoscopy). The secondary outcomes were the investigation of the intention to adopt new methods of saliva sampling. We collected saliva samples from children subjected to invasive medical procedures, with the aim of applying the Theory of Planned Behavior (TPB) as an intervention means to provide information and education to both parents and children undergoing stressful situations, and assess its efficacy in reducing stress levels. We also aimed at acquiring a better understanding of the acceptability of noninvasive biomarker collection in community settings. (2) Methods: The sample of this prospective study comprised 81 children who underwent surgical or endoscopic procedures at the Attikon General University Hospital, Athens, Greece and 90 parents. The sample was divided into two groups. The first, 'Group Unexplained', was not provided any information or education about the procedures, while the second, 'Group Explained', was informed and educated based on TPB. Thereafter, 8-10 weeks after intervention, the Theory of Planned Behavior questions were re-completed by the 'Group Explained'. (3) Results: Significant differences were detected in cortisol and amylase values between the two groups postoperatively after applying the TPB intervention. Saliva cortisol was reduced by 8.09 ng/mL in the 'Group Explained' while in the 'Group Unexplained' it was reduced by 4.45 ng/mL (p < 0.001). Salivary amylase values decreased by 9.69 ng/mL in the 'Group Explained' after the intervention phase of the study, while in the 'Group Unexplained' they increased by 35.04 ng/mL (p < 0.001). The regression explains 40.3% (baseline) and 28.5% (follow-up) of parental intention. The predictive factor of parental intention (baseline) is attitude (p < 0.001) and follow-up is behavioral control (p < 0.028) and attitude (p < 0.001). (4) Conclusions: Providing proper education and information for parents has a positive effect on reducing children's stress levels. Changing parental attitudes towards saliva collection plays the most important role, since a positive attitude can influence intention and ultimately participation in these procedures.

A subpopulation of agouti-related peptide neurons exciting corticotropin-releasing hormone axon terminals in median eminence led to hypothalamic-pituitary-adrenal axis activation in response to food restriction

The excitatory action of gamma-aminobutyric-acid (GABA) in the median-eminence (ME) led to the steady-state release of corticotropin-releasing hormone (CRH) from CRH axon terminals, which modulates the hypothalamic-pituitary-adrenal (HPA) axis. However, in ME, the source of excitatory GABAergic input is unknown. We examined agouti-related peptide (AgRP) expressing neurons in the arcuate nucleus as a possible source for excitatory GABAergic input. Here, we show that a subpopulation of activated AgRP neurons directly project to the CRH axon terminals in ME elevates serum corticosterone levels in 60% food-restricted mice. This increase in serum corticosterone is not dependent on activation of CRH neuronal soma in the paraventricular nucleus. Furthermore, conditional deletion of Na⁺-K⁺-2Cl^– cotransporter-1 (NKCC1), which promotes depolarizing GABA action, from the CRH axon terminals results in significantly lower corticosterone levels in response to food restriction. These findings highlight the important role of a subset of AgRP neurons in HPA axis modulation via NKCC1-dependent GABAergic excitation in ME.

The VH framework region 1 as a target of efficient mutagenesis for generating a variety of affinity-matured scFv mutants

In vitro affinity-maturation potentially generates antibody fragments with enhanced antigen-binding affinities that allow for developing more sensitive diagnostic systems and more effective therapeutic agents. Site-directed mutagenesis targeting “hot regions,” i.e., amino acid substitutions therein frequently increase the affinities, is desirable for straightforward discovery of valuable mutants. We here report two “designed” site-directed mutagenesis (A and B) targeted the N-terminal 1–10 positions of the V_H framework region 1 that successfully improved an anti-cortisol single-chain Fv fragment (K_a, 3.6 × 10⁸ M⁻¹). Mutagenesis A substituted the amino acids at the position 1–3, 5–7, 9 and 10 with a limited set of substitutions to generate only 1,536 different members, while mutagenesis B inserted 1–6 random residues between the positions 6 and 7. Screening the resulting bacterial libraries as scFv-phage clones with a clonal array profiling system provided 21 genetically unique scFv mutants showing 17–31-fold increased affinity with > 10⁹ M⁻¹K_a values. Among the mutants selected from the library A and B, scFv mA#18 (with five-residue substitutions) and mB_1-3#130 (with a single residue insertion) showed the greatest K_a value, 1.1 × 10¹⁰ M⁻¹.

Downregulation of the GHRH/GH/IGF1 axis in a mouse model of Börjeson-Forssman-Lehman syndrome

Börjeson-Forssman-Lehmann syndrome (BFLS) is an intellectual disability and endocrine disorder caused by plant homeodomain finger 6 (PHF6) mutations. Individuals with BFLS present with short stature. We report a mouse model of BFLS, in which deletion of Phf6 causes a proportional reduction in body size compared with control mice. Growth hormone (GH) levels were reduced in the absence of PHF6. Phf6 ^{- /Y} animals displayed a reduction in the expression of the genes encoding GH-releasing hormone (GHRH) in the brain, GH in the pituitary gland and insulin-like growth factor 1 (IGF1) in the liver. Phf6 deletion specifically in the nervous system caused a proportional growth defect, indicating a neuroendocrine contribution to the phenotype. Loss of suppressor of cytokine signaling 2 (SOCS2), a negative regulator of growth hormone signaling partially rescued body size, supporting a reversible deficiency in GH signaling. These results demonstrate that PHF6 regulates the GHRH/GH/IGF1 axis.

Clonal array profiling of scFv-displaying phages for high-throughput discovery of affinity-matured antibody mutants

"Antibody-breeding" approach potentially generates therapeutic/diagnostic antibody mutants with greater performance than native antibodies. Therein, antibody fragments (e.g., single-chain Fv fragments; scFvs) with a variety of mutations are displayed on bacteriophage to generate diverse phage-antibody libraries. Rare clones with improved functions are then selected via panning against immobilized or tagged target antigens. However, this selection process often ended unsuccessful, mainly due to the biased propagation of phage-antibody clones and the competition with a large excess of undesirable clones with weaker affinities. To break radically from such panning-inherent problems, we developed a novel method, clonal array profiling of scFv-displaying phages (CAP), in which colonies of the initial bacterial libraries are examined one-by-one in microwells. Progenies of scFv-displaying phages generated are, if show sufficient affinity to target antigen, captured in the microwell via pre-coated antigen and detected using a luciferase-fused anti-phage scFv. The advantage of CAP was evidenced by its application with a small error-prone-PCR-based library (~ 10⁵ colonies) of anti-cortisol scFvs. Only two operations, each surveying only ~ 3% of the library (9,400 colonies), provided five mutants showing 32–63-fold improved K_a values (> 10¹⁰ M⁻¹), compared with the wild-type scFv (K_a = 3.8 × 10⁸ M⁻¹), none of which could be recovered via conventional panning procedures operated for the entire library.

Beyond Glucocorticoids: Integrating Dehydroepiandrosterone (DHEA) into Animal Welfare Research

Animal welfare researchers are committed to identifying novel measures for enhancing the quality of life of individual animals. Recently, welfare scientists have emphasized the need for tracking multiple indicators of an animal's behavioral, emotional and mental health. Researchers are currently focused on integrating non-invasive physiological biomarkers to gain insight into an individual's welfare status. Most commonly, the animal welfare community has analyzed glucocorticoid hormones and their metabolites as a measure of stress. While glucocorticoids provide valuable information about hypothalamic-pituitary-adrenal (HPA) axis activity, there are limitations to utilizing these hormones as the sole measure of long-term stress and welfare. Other biomarkers, such as dehydroepiandrosterone and its sulfate ester-collectively referred to as DHEA(S)-help provide a more complete picture of HPA activity. DHEA(S) counteracts the effects glucocorticoids by having anti-aging, immune-enhancing and neuroprotective properties. Recent studies have examined the ratio of glucocorticoids to DHEA(S) as a way to better understand how the HPA axis is functioning. There is evidence that this ratio serves as an indicator of immune function, mental health, cognitive performance and overall welfare. We review studies that employed the glucocorticoid:DHEA(S) ratio, outline methodological considerations and discuss how researchers can integrate glucocorticoids, DHEA(S) and the glucocorticoid:DHEA(S) ratio into welfare assessments.

Preparatory information reduces gastroscopy-related stress in children as confirmed by salivary cortisol

BACKGROUND/AIMS

This study aimed to determine whether the anxiety levels of pediatric patients who undergo endoscopy are reduced after receiving preparatory information about the endoscopic procedure by monitoring their salivary cortisol (s-cortisol) levels.

PATIENTS AND METHODS

A total of 184 children undergoing gastroscopy under sedoanalgesia were included in the study. All the patients received a brief explanation of the endoscopic procedure. Patients were divided into two groups; Group Unexplained did not receive any further information other than a brief explanation of the procedure, Group Explained received more detailed explanation of the procedure. To determine anxiety levels, saliva specimens were taken on the day before the procedure to examine cortisol levels before and after endoscopy. Anxiety scores before endoscopy were calculated by the modified Yale Preoperative Anxiety Scale. Patients were monitored throughout sedoanalgesia, including during the endoscopy, sedation and recovery, and total propofol dosages were recorded.

RESULTS

Eighty-nine children undergoing gastroscopy (age 11.55 ± 2.52 years; 50.5% girls) constituted Group Explained and 95 children undergoing gastroscopy (age 11.44 ± 2.66 years; 56.8% male) constituted Group Unexplained. The anxiety score, duration of sedation, endoscopy and recovery, propofol dose, pre- and post-endoscopy s-cortisol levels were significantly reduced in Group Explained.

CONCLUSIONS

We demonstrated that when endoscopic procedure is explained broadly to a child, the procedural stress is significantly less, as measured by the s-cortisol levels and the anxiety questionnaire. It is important for the attending physician to explain all aspects of examination carefully.

Anxiety and Salivary Cortisol Levels in Children Undergoing Esophago-Gastro-Duodenoscopy Under Sedation

OBJECTIVES

Esophagogastroduodenoscopy (EGD) can cause fear and anxiety in children. Cortisol, which is the most important glucocorticoid hormone in humans, can increase under physiological stress. The purpose of this study was to measure the salivary cortisol level (SCL) and anxiety level in patients undergoing EGD and evaluate their effects on the procedure.

METHODS

Children undergoing EGD under sedoanalgesia with propofol for various reasons were included. Their basal SCLs were compared with those of healthy age- and sex-matched controls. Moreover, SCL of the patient group at 30 minutes before EGD and 2 hours after the procedure were measured. Their anxiety scores were calculated using the modified Yale Preoperative Anxiety Scale before EGD. Duration of endoscopy, sedation, and recovery and total propofol doses were recorded.

RESULTS

Demographic properties of the patient group (n = 119; 10.9 ± 3.2 years; 43.7% boys) and control group (n = 85; 11.8 ± 2.8 years; 45.1% boys) were not significantly different. Basal SCLs of both groups were similar (16.9 ± 0.7 vs 19.7 ± 1.8 ng/mL, P = 0.16). SCL before EGD in the patient group was significantly higher than basal and post-EGD values (P < 0.001 for each). Pre-EGD SCL was positively correlated with anxiety level, propofol dose, and duration of sedation, procedure, and recovery. Anxiety levels of patients were positively correlated with propofol dose and duration of sedation and recovery, and negatively correlated with age.

CONCLUSIONS

Childhood EGD is a significant stress factor, which was reflected by the pre-procedural SCL in this study. Increased anxiety resulted in increased propofol doses and sedoanalgesia-related procedural durations, which may cause potential complications.

Stress as a Risk Factor for Substance Use Disorders: A Mini-Review of Molecular Mediators

The extant literature supports the role of stress in enhancing the susceptibility of drug abuse progressing to a substance use disorder diagnosis. However, the molecular mediators by which stress enhances the progression from cocaine abuse to cocaine use disorder via the mesolimbic pathway remain elusive. In this mini-review article, we highlight three mechanisms by which glucocorticoids (GCs) and the dopaminergic system interact. First, GCs upregulate tyrosine hydroxylase (TH), the rate-limiting enzyme in dopamine (DA) synthesis. Second, GCs downregulate monoamine-oxidase (MAO), an enzyme responsible for DA removal. Lastly, GCs are hypothesized to decrease DA reuptake, subsequently increasing synaptic DA. Based on these interactions, we review preclinical literature highlighting how stress modulates the mesolimbic pathway, including the ventral tegmental area (VTA) and nucleus accumbens (NAcs), to alter cocaine abuse-related effects. Taken together, stress enhances cocaine's abuse-related effects at multiple points along the VTA mesolimbic projection, and uniquely in the NAcs through a positive feedback type mechanism. Furthermore, we highlight future directions to elucidate the interaction between the prefrontal cortex (PFC) and key intermediaries including ΔFosB, cAMP response element binding protein (CREB) and cyclin-dependent kinase 5 (CDK5) to highlight possible mechanisms that underlie stress-induced acceleration of the progression to a cocaine use disorder diagnosis.

Central adrenal insufficiency in children and adolescents

Central adrenal insufficiency (CAI) is a life-threatening condition caused by either pituitary disease (secondary adrenal insufficiency) or impaired hypothalamic function with inadequate CRH production (tertiary adrenal insufficiency). ACTH deficiency may be isolated or, more frequently, occur in conjunction with other pituitary hormone deficiencies and midline defects. Genetic mutations of the TBX19 causing isolated CAI are rare but a number of genes encoding transcription factors involved in hypothalamic-pituitary gland development, as well as other genes including POMC and PC1, are associated with ACTH deficiency. CAI is frequently identified in congenital, malformative, genetic, and epigenetic syndromes as well as in several acquired conditions of different etiologies. The signs and symptoms vary considerably and depend on the age of onset and the number and severity of associated pituitary defects. They may include hypoglycemia, lethargy, apnea, poor feeding, prolonged cholestatic jaundice, jitteriness, seizures, and sepsis in the neonate, or nonspecific signs such as fatigue, hypotension, vomiting and hyponatremia without hyperkalemia in children. The diagnosis of CAI relies on the measurement of morning cortisol concentrations along with dynamic test for cortisol release with different stimulating agents. Early recognition of CAI and its correct management are mandatory in order to avoid both morbidity and mortality in affected neonates, children and adolescents.

A Single-Step "Breeding" Generated a Diagnostic Anti-cortisol Antibody Fragment with Over 30-Fold Enhanced Affinity

Cortisol levels in bodily fluids represent a useful index for pituitary-adrenal function, and thus practical anti-cortisol antibodies are required. We have studied "antibody-breeding" approaches, which involve in vitro evolution of antibodies to improve their antigen-binding performances. Here, we produced an antibody fragment to measure serum cortisol levels with over 30-fold enhanced affinity after single mutagenesis and selection steps. A mouse anti-cortisol antibody, Ab-CS#3, with insufficient affinity for practical use, was chosen as the prototype antibody. A "wild-type" single-chain Fv fragment (wt-scFv; K_a, 3.4×10⁸ M^-1) was prepared by bacterial expression of a fusion gene combining the V_H and V_L genes for this antibody. Then, random point mutations were generated separately in V_H or V_L by error-prone PCR, and the resulting products were used to assemble scFv genes, which were displayed on filamentous phages. Repeated panning of the phage library identified a mutant scFv (scFv#m1-L10) with an over 30-fold enhanced affinity (K_a 1.2×10¹⁰ M^-1). Three amino acid substitutions (Cys49Ser, Leu54Pro, and Ser63Gly) were observed in its V_L sequence. In a competitive enzyme-linked immunosorbent assay (ELISA), the mutant scFv generated dose-response curves with measuring range ca. 0.03-0.6 ng/assay cortisol, midpoint of which (0.15 ng/assay) was 7.3-fold lower than that of wt-scFv. Although cortisone, 11-deoxycortisol, and prednisolone showed considerable cross-reactivity, the mutant scFv should enable sensitive routine cortisol assays, except for measurement after metyrapone or high-dose of prednisolone administrations. Actually, cortisol levels of control sera obtained with the scFv-based ELISA were in the reference range.

The HPA axis and ethanol: a synthesis of mathematical modelling and experimental observations

Stress and alcohol use are interrelated-stress contributes to the initiation and upholding of alcohol use and alcohol use alters the way we perceive and respond to stress. Intricate mechanisms through which ethanol alters the organism's response to stress remain elusive. We have developed a stoichiometric network model to succinctly describe neurochemical transformations underlying the stress response axis and use numerical simulations to model ethanol effects on complex daily changes of blood levels of cholesterol, 6 peptide and 8 steroid hormones. Modelling suggests that ethanol alters the dynamical regulation of hypothalamic-pituitary-adrenal (HPA) axis activity by affecting the amplitude of ultradian oscillations of HPA axis hormones, which defines the threshold with respect to which the response to stress is being set. These effects are complex-low/moderate acute ethanol challenge (<8 mM) may reduce, leave unaltered or increase the amplitude of ultradian cortisol (CORT) oscillations, giving rise to an intricate response at the organism level, offering also a potential explanation as to why apparently discordant results were observed in experimental studies. In contrast, high-dose acute ethanol challenge (>8 mM) increases instantaneous CORT levels and the amplitude of ultradian CORT oscillations in a dose-dependent manner, affecting the HPA axis activity also during the following day(s). Chronic exposure to ethanol qualitatively changes the HPA axis dynamics, whereas ethanol at intoxicating levels shuts down this dynamic regulation mechanism. Mathematical modelling gives a quantitative biology-based framework that can be used for predicting how the integral HPA axis response is perturbed by alcohol.

Efficacy of the novel nasal steroid S0597 tested in an environmental exposure unit

BACKGROUND

S0597 is a novel glucocorticosteroid that was formulated as an intranasal spray to treat seasonal allergic rhinitis (SAR). In a previous phase 2 study, doses of 100 to 400 μg twice daily were well tolerated and more effective than placebo for improving nasal symptoms induced by grass pollen.

OBJECTIVE

To assess the clinical efficacy and safety of a once-daily S0597 nasal spray for treatment of SAR induced by ragweed pollen in an environmental exposure unit (EEU).

METHODS

A single-center, phase 2, randomized, double-blind study in 222 adults with SAR and a positive skin prick test result to short ragweed. Participants underwent ragweed pollen challenge in the EEU at the screening or priming visit and on days 1, 7, and 14 and received 50, 200, or 400 μg of S0597 or placebo in the evening for 13 days. The primary efficacy end point was change in total nasal symptom score (TNSS) from baseline to day 14.

RESULTS

Improvement in TNSS from baseline to day 14 was statistically significant in all S0597 groups compared with placebo. Least-squares mean differences in change from baseline between active treatment and placebo were 1.18, 1.84, and 1.17 for the 50-, 200-, and 400-μg/d S0597 groups, respectively (P < .05). The 200-μg group demonstrated statistically significant improvements in all TNSS subscales (rhinorrhea, nasal congestion, sneezing, nasal itching) compared with placebo at days 7 and 14.

CONCLUSION

Treatment with 50 to 400 μg of S0597 once daily was well tolerated and significantly more effective than placebo in relieving nasal symptoms of SAR associated with ragweed pollen.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01940146.

Cortisol and DHEA in development and psychopathology

Dehydroepiandrosterone (DHEA) and cortisol are the most abundant hormones of the human fetal and adult adrenals released as end products of a tightly coordinated endocrine response to stress. Together, they mediate short- and long-term stress responses and enable physiological and behavioral adjustments necessary for maintaining homeostasis. Detrimental effects of chronic or repeated elevations in cortisol on behavioral and emotional health are well documented. Evidence for actions of DHEA that offset or oppose those of cortisol has stimulated interest in examining their levels as a ratio, as an alternate index of adrenocortical activity and the net effects of cortisol. Such research necessitates a thorough understanding of the co-actions of these hormones on physiological functioning and in association with developmental outcomes. This review addresses the state of the science in understanding the role of DHEA, cortisol, and their ratio in typical development and developmental psychopathology. A rationale for studying DHEA and cortisol in concert is supported by physiological data on the coordinated synthesis and release of these hormones in the adrenal and by their opposing physiological actions. We then present evidence that researching cortisol and DHEA necessitates a developmental perspective. Age-related changes in DHEA and cortisol are described from the perinatal period through adolescence, along with observed associations of these hormones with developmental psychopathology. Along the way, we identify several major knowledge gaps in the role of DHEA in modulating cortisol in typical development and developmental psychopathology with implications for future research.

Longitudinal and Immediate Effect of Kundalini Yoga on Salivary Levels of Cortisol and Activity of Alpha-Amylase and Its Effect on Perceived Stress

Context:

Stress is defined as an alteration of an organism's balance in response to a demand perceived from the environment. Diverse methods exist to evaluate physiological response. A noninvasive method is salivary measurement of cortisol and alpha-amylase. A growing body of evidence suggests that the regular practice of Yoga would be an effective treatment for stress.

Aims:

To determine the Kundalini Yoga (KY) effect, immediate and after 3 months of regular practice, on the perception of psychological stress and the salivary levels of cortisol and alpha-amylase activity.

Settings and Design:

To determine the psychological perceived stress, levels of cortisol and alpha-amylase activity in saliva, and compare between the participants to KY classes performed for 3 months and a group that does not practice any type of yoga.

Subjects and Methods:

The total sample consisted of 26 people between 18 and 45-year-old; 13 taking part in KY classes given at the Faculty of Dentistry, University of Chile and 13 controls. Salivary samples were collected, enzyme-linked immunosorbent assay was performed to quantify cortisol and kinetic reaction test was made to determine alpha-amylase activity. Perceived Stress Scale was applied at the beginning and at the end of the intervention.

Statistical Analysis Used:

Statistical analysis was applied using Stata v11.1 software. Shapiro–Wilk test was used to determine data distribution. The paired analysis was fulfilled by t-test or Wilcoxon signed-rank test. T-test or Mann–Whitney's test was applied to compare longitudinal data. A statistical significance was considered when P < 0.05.

Results:

KY practice had an immediate effect on salivary cortisol. The activity of alpha-amylase did not show significant changes. A significant decrease of perceived stress in the study group was found.

Conclusions:

KY practice shows an immediate effect on salivary cortisol levels and on perceived stress after 3 months of practice.

A Single Postnatal Dose of Dexamethasone Enhances Memory of Rat Pups Later in Life

Postnatal dexamethasone (Dex) therapy is associated with adverse neurodevelopmental outcomes, which might be related to its timing of administration. We used time-dated pregnant Wistar albino rats, whose litters were divided into experimental (Dex) and control groups intraperitoneally administered one dose of Dex (0.5 mg/kg) or normal saline (NS), respectively, at either day 1 (P1) or 7 (P7). The magnitude of the contextual freezing response and performance on the Morris water maze were significantly higher in the Dex-P7 group than in those of the other groups at P56. Dendritic spine density, membranous expression of the N-methyl-d-aspartate receptor (NMDAR) subunit NR2A/2B, and postsynaptic density-95 (PSD-95) were significantly higher in the Dex-P7 group than in the other groups. Furthermore, cytosolic expression of nuclear factor kappa B (NF-κB) and phosphatidylinositol 3-kinase (PI3K) was significantly higher in the Dex group than in NS group. Moreover, Dex administration at P7 increased cell proliferation, neuronal differentiation, and the survival of newly born neurons in the dentate gyrus. These results suggest Dex at P7 enhances the acquisition of contextual fear and spatial memory later in life due to the modulation of the newly born neurons, increase in dendritic spine number, and NMDAR expression.

LC-MS based analysis of endogenous steroid hormones in human hair

The quantification of endogenous steroid hormone concentrations in hair is increasingly used as a method for obtaining retrospective information on long-term integrated hormone exposure. Several different analytical procedures have been employed for hair steroid analysis, with liquid chromatography-mass spectrometry (LC-MS) being recognized as a particularly powerful analytical tool. Several methodological aspects affect the performance of LC-MS systems for hair steroid analysis, including sample preparation and pretreatment, steroid extraction, post-incubation purification, LC methodology, ionization techniques and MS specifications. Here, we critically review the differential value of such protocol variants for hair steroid hormones analysis, focusing on both analytical quality and practical feasibility issues. Our results show that, when methodological challenges are adequately addressed, LC-MS protocols can not only yield excellent sensitivity and specificity but are also characterized by relatively simple sample processing and short run times. This makes LC-MS based hair steroid protocols particularly suitable as a high-quality option for routine application in research contexts requiring the processing of larger numbers of samples.

Reductions in circulating endocannabinoid 2-arachidonoylglycerol levels in healthy human subjects exposed to chronic stressors

Increasing evidence indicates that chronic stress, such as social isolation, plays an important role in the development of a variety of psychiatric and somatic disorders. Meanwhile, chronic stress imposed by prolonged isolation and confinement in the spacecraft is also one of the major concerns for the health of future interplanetary space travelers. Preclinical studies suggest that the peripheral endocannabinoid (eCB) system is involved in the regulation of the stress response and eCB signaling is implicated in the pathogenesis of stress-related diseases. However, there are only few human studies addressing this topic, of which most focusing on patients who have already developed a certain type of disorder. It remains unknown whether chronic stress may affect eCB signaling in healthy humans. A 520-d isolation and confinement study simulating a flight to Mars provided an extraordinary chance to study the effects of prolonged stress in healthy humans. During the study period, the participants lived in confinement and could not meet their families, friends, or strangers for more than 500 days. We examined the impact of chronic exposure to isolation and confinement through monitoring their psychological state, brain cortical activity, sympathetic adrenal-medullary system response and eCB signaling response. We observed reduced positive emotion ratings, decreased brain cortical activities and high levels of catecholamine release, indicating that prolonged exposure to isolation and confinement stressors may bring about changes both psychologically and physiologically. Importantly, for eCB signaling response, blood concentrations of eCB 2-arachidonoylglycerol (2-AG), but not anandamide (AEA), were significantly reduced (p<0.001), suggesting that dysregulation of 2-AG signaling might be specifically implicated in the response to chronic stressors.

Hypothalamic-pituitary-adrenal axis in HIV infection and disease

HIV infection induces hypothalamic-pituitary-adrenal (HPA) axis derangements. Partial glucocorticoid resistance has been observed in a subset of AIDS patients, possibly owing to HIV-induced altered cytokine secretion and action. Because glucocorticoids have immunomodulatory effects, the severity of the HPA axis disorder could play a central role in disease progression. The characteristic phenotype of AIDS patients (visceral obesity, lipodystrophy) may be owing to effects of HIV proteins on the HPA axis, including changes in glucocorticoid and insulin sensitivity of target tissues, as well as altered cytokine production and interaction with the HPA axis, genetic causes, comorbidities, and, possibly, use of antiretroviral agents.

Adrenal insufficiency

Adrenal insufficiency is the clinical manifestation of deficient production or action of glucocorticoids, with or without deficiency also in mineralocorticoids and adrenal androgens. It is a life-threatening disorder that can result from primary adrenal failure or secondary adrenal disease due to impairment of the hypothalamic-pituitary axis. Prompt diagnosis and management are essential. The clinical manifestations of primary adrenal insufficiency result from deficiency of all adrenocortical hormones, but they can also include signs of other concurrent autoimmune conditions. In secondary or tertiary adrenal insufficiency, the clinical picture results from glucocorticoid deficiency only, but manifestations of the primary pathological disorder can also be present. The diagnostic investigation, although well established, can be challenging, especially in patients with secondary or tertiary adrenal insufficiency. We summarise knowledge at this time on the epidemiology, causal mechanisms, pathophysiology, clinical manifestations, diagnosis, and management of this disorder.

The role of hypocortisolism in chronic fatigue syndrome

BACKGROUND

There is accumulating evidence of hypothalamic-pituitary-adrenal (HPA) axis hypofunction in chronic fatigue syndrome (CFS). However, knowledge of this hypofunction has so far come exclusively from research in adulthood, and its clinical significance remains unclear. The objective of the current study was to assess the role of the HPA-axis in adolescent CFS and recovery from adolescent CFS.

METHOD

Before treatment, we compared the salivary cortisol awakening response of 108 diagnosed adolescent CFS patients with that of a reference group of 38 healthy peers. Salivary cortisol awakening response was measured again after 6 months of treatment in CFS patients.

RESULTS

Pre-treatment salivary cortisol levels were significantly lower in CFS-patients than in healthy controls. After treatment recovered patients had a significant rise in salivary cortisol output attaining normalization, whereas non-recovered patients improved slightly, but not significantly. The hypocortisolism found in CFS-patients was significantly correlated to the amount of sleep. Logistic regression analysis showed that an increase of one standard deviation in the difference between pre- and post-treatment salivary cortisol awakening response was associated with a 93% higher odds of recovery (adjusted OR 1.93 (1.18 to 3.17), p=0.009). Pre-treatment salivary cortisol did not predict recovery.

CONCLUSIONS

Hypocortisolism is associated with adolescent CFS. It is not pre-treatment cortisol but its change to normalization that is associated with treatment success. We suggest that this finding may have clinical implications regarding the adaptation of future treatment strategies.

Inhaled corticosteroids and secondary adrenal insufficiency

Inhaled corticosteroids (ICS) have been used as first line treatment of asthma for many decades. ICS are a form of exogenous glucocorticosteroids that can suppress the endogenous production of glucocorticosteroids, a condition known as adrenal suppression (AS). As a result, cessation, decreasing the dose or changing the type of ICS may trigger features of adrenal insufficiency (AI). AI may cause a spectrum of presentations varying from vague symptoms of fatigue to potentially life threatening acute adrenal crises. This article reviews the current literature on ICS and AI particularly in adults (although majority of data available is from the paediatric population). It aims to increase awareness of the potential risk of AI associated with ICS use, delineate the pathogenesis of AI and to provide recommendations on screening and management. From our literature review, we have found numerous case reports that have shown an association between ICS and AI particularly in children and patients using high doses. However, there have also been reports of AI in adults as well as in patients using low to moderate doses of ICS. To conclude, we recommend screening for AI in select patient groups with an initial early morning serum cortisol. If results are abnormal, more definitive testing such as the low dose corticotropin stimulation test may be done to confirm the diagnosis.

Endocrinopathies in survivors of childhood neoplasia

Advancements in cancer treatments have increased the number of survivors of childhood cancers. Endocrinopathies are common complications following cancer therapy and may occur decades later. The objective of the current review is to address the main endocrine abnormalities detected in childhood cancer survivors including disorders of the hypothalamic-pituitary axis, thyroid, puberty, gonads, bone, body composition, and glucose metabolism.

Association of obesity-mediated insulin resistance and hypothalamic volumes: possible sex differences

The hypothalamus is important in hunger and metabolism. Although a lot is known about the basic role of the human hypothalamus, less is known about how the in vivo volume is affected in obesity, particularly among adolescents. Based on pediatric body mass index percentiles, 95 participants were assigned to lean or obese groups. All subjects had medical evaluations, including fasting blood tests, to assess insulin sensitivity and circulating CRP and neurotrophins (NGF and BDNF) and an MRI of the brain. Hypothalamic volumes were measured by a segmentation method combining manual and automated steps. Overall, obese participants had descriptively smaller hypothalamic volumes, although this difference did not reach statistical significance; however, among obese participants, females had significantly smaller hypothalamic volumes than their male counterparts. There was a significant interaction between insulin resistance and sex on hypothalamus volume; obese females with significant insulin resistance have smaller hypothalamic volumes than obese males. Obese adolescents had higher circulating CRP and neurotrophin levels. Furthermore, among obese females, BDNF concentrations were inversely associated with hypothalamus volumes (r = −0.48). Given this negative association between BDNF and hypothalamus volumes among obese insulin-resistant females, elevated neurotrophin levels may suggest an attempt at protective compensation.

The -2T/C polymorphism in the adrenocorticotropin receptor gene affects stress perception of patients with alopecia areata

BACKGROUND

Altered hypothalamic-pituitary-adrenal (HPA) axis response involved in the pathogenesis of stress-associated alopecia areata (AA) has been reported. A novel polymorphism -2T>C of the adrenocorticotropin receptor (ACTHR) can result in an insufficient HPA response to stress; therefore, the functional polymorphism may underlie a role in stress-associated AA.

OBJECTIVE

To investigate the relationship between psychosocial factors and the risk of developing AA and to detect the association between the -2T>C polymorphism of ACTHR and AA.

METHODS

Stressful situations were evaluated using Holmes and Rahe's social readjustment rating scale. The ACTHR -2T>C polymorphism was examined in 263 patients with AA and 241 controls.

RESULTS

Significant elevation of psychological stress experienced by some patients with AA compared with controls (Z = 6.628, P < 0.01). The frequency of the ACTHR C allele showed a significant difference between patients with AA and controls (P = 0.004). Allele C is the risk allele with a dominant model as the -2C allele occurred more often in patients with AA (P = 0.001). There were significant differences between patients with AA with a severe stress attack versus patients with AA with no obvious stress (P < 0.001), whereas the genotype frequencies were not correlated with the type, duration of disease, and age at onset. Notably, the C allele carrier was significantly associated with stress risk in both AA and controls (P = 0.002, OR = 1.576, 95% CI: 1.148-2.162; P = 0.042, OR = 1.529, 95% CI: 1.022-2.288).

CONCLUSIONS

These findings suggest AA in some patients may be associated with stress. The ACTHR gene -2T>C variant may be one important factor that influences stress perception of patients with AA.

Acute stress increases circulating anandamide and other N-acylethanolamines in healthy humans

Stress plays an important role in psychiatric disorders, and preclinical evidence indicates that the central endocannabinoid system modulates endocrine and neuronal responses to stress. This study aimed to investigate the effect of acute stress on circulating concentrations of endocannabinoids (eCBs) in healthy humans. A total of 71 adults participated in two sessions in which they were exposed to either a standardized psychosocial stress procedure (Trier Social Stress Test) or a control task. Blood samples for eCB and cortisol assays and cardiovascular and subjective measures were obtained before and at regular intervals after the tasks. Serum concentrations of the eCBs, N-arachidonylethanolamine (anandamide, AEA) and 2-arachidonoylglycerol (2-AG), as well as of the N-acylethanolamides (NAEs), N-palmitoylethanolamine (PEA) and N-oleoylethanolamine (OEA), and of the O-acylglycerol, 2-oleoylglycerol (2-OG), were determined. Compared with the control condition, stress increased serum concentrations of AEA and the other NAEs immediately after the stress period. Increases in PEA were positively correlated with increases in serum cortisol after stress. Furthermore, anxiety ratings at baseline were negatively correlated with baseline concentrations of AEA. The sex and menstrual cycle status of the subject affected the NAE responses to stress. Interestingly, subjects of Asian and African-American races exhibited different patterns of stress responses compared with the Caucasian subjects. These results indicate that stress increases circulating NAEs in healthy human volunteers. This finding supports a protective role for eCBs in anxiety. Further research is needed to elucidate the function of these lipid mediators, and to determine the mechanisms that regulate their appearance in the circulation.

Hypothalamic-pituitary-adrenal axis dysfunction as a neurobiological correlate of emotion dysregulation in adolescent suicide

BACKGROUND

Biological markers of vulnerability for current or future risk of suicide in adolescents could be important adjuncts to the treatment and prevention of this phenomenon.

DATA SOURCES

We conducted a PubMed search of all English-language articles published between January 1990 and June 2011 using the following search terms: ("hypothalamic-pituitary-adrenal" OR "HPA") AND ("adolescence" OR "adolescent" OR "teenager") AND ("depression" OR "major depressive disorder" OR "suicidal behavior" OR "suicidal ideation" OR "suicidal thoughts" OR "deliberate self-harm" OR "suicidal attempt" OR "suicide").

RESULTS

HPA axis activity can be examined using different methods that do not have the same biological interpretation. An abnormal HPA axis functioning together with an anomalous interaction between HPA mechanisms and other systems such as the serotonergic system may be one of the neurobiological correlates of emotion dysregulation (ED). ED may play an important role in adolescent suicidal behavior. Some psychopathological conditions such as depression or childhood psychological trauma that increase suicidal risk in adolescents are also associated with HPA axis dysregulation. ED, a personality trait, can also be viewed as a predisposing factor that augments the vulnerability to suffer from psychiatric conditions.

CONCLUSIONS

Correlating HPA axis dysfunction with psychological factors such as ED could lead to a better understanding of the role of HPA abnormalities in adolescent suicide and may enhance preventive and treatment strategies.

Endocannabinoids and the cardiovascular response to stress

Stress activates the hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS), resulting in cardiovascular responses. The endocannabinoid system (ECS), a ubiquitously expressed lipid signalling system, modulates both HPA and SNS activity. The purpose of this review is to explore the possible involvement/role of the ECS in the cardiovascular response to stress. The ECS has numerous cardiovascular effects including modulation of blood pressure, heart rate, the baroreflex, and direct vascular actions. It is also involved in a protective manner in response to stressors in cardiac preconditioning, and various stressors (for example, pain, orthostasis and social stress) increase plasma levels of endocannabinoids. Given the multitude of vascular effects of endocannabinoids, this is bound to have consequences. Beneficial effects of ECS upregulation could include cardioprotection, vasodilatation, CB(2)-mediated anti-inflammatory effects and activation of peroxisome proliferator-activated receptors. Negative effects of endocannabinoids could include mediation of the effects of glucocorticoids, CB(1)-mediated metabolic changes, and metabolism to vasoconstrictor products. It is also likely that there is a central role for the ECS in modulating cardiovascular activity via the HPA and SNS. However, much more work is required to fully integrate the role of the ECS in mediating many of the physiological responses to stress, including cardiovascular responses.

Adrenal suppression: A practical guide to the screening and management of this under-recognized complication of inhaled corticosteroid therapy

Inhaled corticosteroids (ICSs) are the most effective anti-inflammatory agents available for the treatment of asthma and represent the mainstay of therapy for most patients with the disease. Although these medications are considered safe at low-to-moderate doses, safety concerns with prolonged use of high ICS doses remain; among these concerns is the risk of adrenal suppression (AS). AS is a condition characterized by the inability to produce adequate amounts of the glucocorticoid, cortisol, which is critical during periods of physiological stress. It is a proven, yet under-recognized, complication of most forms of glucocorticoid therapy that can persist for up to 1 year after cessation of corticosteroid treatment. If left unnoticed, AS can lead to significant morbidity and even mortality. More than 60 recent cases of AS have been described in the literature and almost all cases have involved children being treated with ≥500 μg/day of fluticasone.

The risk for AS can be minimized through increased awareness and early recognition of at-risk patients, regular patient follow-up to ensure that the lowest effective ICS doses are being utilized to control asthma symptoms, and by choosing an ICS medication with minimal adrenal effects. Screening for AS should be considered in any child with symptoms of AS, children using high ICS doses, or those with a history of prolonged oral corticosteroid use. Cases of AS should be managed in consultation with a pediatric endocrinologist whenever possible. In patients with proven AS, stress steroid dosing during times of illness or surgery is needed to simulate the protective endogenous elevations in cortisol levels that occur with physiological stress.

This article provides an overview of current literature on AS as well as practical recommendations for the prevention, screening and management of this serious complication of ICS therapy.

The limbic-hypothalamic-pituitary-adrenal axis and the development of alcohol use disorders in youth

OBJECTIVE

As the initiation and acceleration of alcohol use commonly occurs during adolescence, the etiological basis for this phenomenon is of critical importance. Using the diathesis-stress model as a framework, this review will evaluate the emerging evidence implicating the limbic-hypothalamic-pituitary-adrenal (LHPA) axis in the development of alcohol use disorder (AUD).

METHOD

Searches were conducted of the PubMed/Medline, PsycInfo, PsycBooks, Cochrane and ISI Web of Science databases, using a specified set of search terms.

RESULTS

Genetic liabilities, antenatal stress/anxiety or exposure to addictive substances, exposure to maltreatment or other traumatic events in childhood and psychiatric illness in childhood/adolescence can all increase the risk, or diathesis, for AUD. Greater LHPA dysfunction may serve as a marker for higher diathesis levels in youth. When exposed to stressors in adolescence, high-risk youth (or those with greater LHPA dysfunction) may use alcohol and/or other substances to cope with stressors and, in turn, become more vulnerable to AUD.

CONCLUSION

Evidence suggests that LHPA dysfunction and stress play an important role in the development of AUD. Genetic liabilities, antenatal insults, maltreatment, and psychiatric illness appear to increase LHPA dysfunction, raising risk for AUD. Further research is needed to clarify the complex interplay among adverse developmental experiences, LHPA dysfunction, and the development of AUD in adolescents.

An implication for post-transcriptional control: reciprocal changes of melanocortin receptor type 2 mRNA and protein expression in alopecia areata

Alopecia areata (AA) is a hair follicle-specific autoimmune disease that is inherited genetically but triggered environmentally. Stress response is believed to play a role in the pathogenesis of AA. The hypothalamic-pituitary-adrenal axis (HPA axis), known as the stress axis, plays a cardinal role in the stress response. Growing evidence demonstrates that stress responses are under the control of both the central and peripheral nervous systems. Skin and hair follicles display peripheral HPA axis-like signaling systems. Some studies have revealed that a modified HPA axis, which is characterized by enhanced CRH/CRHR and insufficient glucocorticoid, is involved in the pathology of AA, suggesting that the paradoxical expression differs from that of normal control and should be further examined. Because adrenocorticotropic hormone (ACTH) is an intermediary in the HPA axis, MC2R, which specifically binds ACTH, may be important in the stress response of skin. Therefore, we investigated the gene and protein expression of MC2R in AA lesions and tried to elucidate the connection between HPA axis regulation, MC2R and AA. Reciprocal changes in MC2R mRNA and proteins in human AA were observed in our study; while mRNA levels were higher in lesions from AA patients compared with scalp tissues from normal controls, protein levels of MC2R were lower. The paradoxical expression of MC2R gene and protein levels coincided with evidence that over-responsive HPA activity coexists with a deficient HPA response in AA. We hypothesized that the HPA axis response in human AA may be the following: stressors first activate excess CRH/CRHR to produce increased ACTH, which up-regulates the expression of MC2R mRNA, but the stress response cannot create sufficient cortisol when the binding of ACTH/MC2R is deficient due to decreased MC2R protein. This hypothesis rationally clarifies the changed HPA axis in human AA and highlights the importance of MC2R in the pathogenesis of AA. The inconsistent expression of protein and mRNA implicates post-transcriptional control of human MC2R gene expression as found in murine MC2R gene.