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Context: Human and animal studies suggest that hypothalamic-pituitary-adrenal axis (HPA-A) function may be programmed in utero; however, these findings are inconsistent. Given the powerful metabolic actions of cortisol, it is important to clarify the influence of early life on adult HPA-A function., Objective: To determine the relationship between fetal growth and HPA-A stress response to a psychosocial stressor in young adults., Design: Multigenerational, prospective cohort study (the Raine Study) conducted between 1989 and 1991., Setting: King Edward Memorial Hospital, Perth, Western Australia, Australia., Participants: A total of 917 participants aged 18 years from Gen2 of the Raine Study., Main Outcome Measures: Measures of hypothalamic-pituitary-adrenal axis function before and after exposure to the Trier Social Stress Test., Results: In fully adjusted models, an inverse linear relationship was observed between birthweight and plasma measures of (1) baseline cortisol (β = -0.90%, 95% CI: -1.73 to -0.07; P = 0.03); (2) peak cortisol (β = -0.78%, 95% CI -1.51 to -0.06; P = 0.03); (3) area under the curve with respect to ground (β = -0.89%, 95% CI -1.60 to -0.18; P = 0.01); and (4) adrenal sensitivity (β = -1.02, 95% CI: -1.85 to -0.18; P = 0.02). Similar results were demonstrated for percent optimal birthweight. No consistent quadratic relationships were identified. No associations were found between measures of fetal adiposity and HPA-A function at age 18 years, or fetal growth and HPA-A response pattern. Removal of anticipatory responders from the models substantially attenuated the observed relationships., Conclusion: We observed an inverse linear relationship between fetal growth and HPA-A function at age 18 years. This differs from the inverse parabolic relationship (inverted U curve) reported in adults of advanced age. Altered adrenal sensitivity may underlie this relationship., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Basic military training (BMT) is a useful model of prolonged exposure to multiple stressors. 8-12 week BMT is associated with perturbations in the hypothalamic-pituitary-adrenal (HPA) axis which could predispose recruits to injury and psychological strain. However, characterisations of HPA axis adaptations during BMT have not been comprehensive and most studies included few if any women., Methods: We studied women undertaking an arduous, 44-week BMT programme in the UK. Anxiety, depression and resilience questionnaires, average hair cortisol concentration (HCC), morning and evening saliva cortisol and morning plasma cortisol were assessed at regular intervals throughout. A 1-h dynamic cortisol response to 1 μg adrenocorticotrophic hormone-1-24 was performed during weeks 1 and 29., Results: Fifty-three women (aged 24 ± 2.5 years) completed the study. Questionnaires demonstrated increased depression and reduced resilience during training (F 6.93 and F 7.24, respectively, both p < 0.001). HCC increased from 3 months before training to the final 3 months of training (median (IQR) 9.63 (5.38, 16.26) versus 11.56 (6.2, 22.45) pg/mg, p = 0.003). Morning saliva cortisol increased during the first 7 weeks of training (0.44 ± 0.23 versus 0.59 ± 0.24 μg/dl p < 0.001) and decreased thereafter, with no difference between the first and final weeks (0.44 ± 0.23 versus 0.38 ± 0.21 μg/dl, p = 0.2). Evening saliva cortisol did not change. Fasting cortisol decreased during training (beginning, mid and end-training concentrations: 701 ± 134, 671 ± 158 and 561 ± 177 nmol/l, respectively, p < 0.001). Afternoon basal cortisol increased during training while there was a trend towards increased peak stimulated cortisol (177 ± 92 versus 259 ± 13 nmol/l, p = 0.003, and 589 ± 164 versus 656 ± 135, p = 0.058, respectively)., Discussion: These results suggest a normal stress response in early training was followed quickly by habituation, despite psychological and physical stress evidenced by questionnaire scores and HCC, respectively. There was no evidence of HPA axis maladaptation. These observations are reassuring for women undertaking arduous employment., (Crown Copyright © 2019. Published by Elsevier Ltd. All rights reserved.)

Purpose: To explore the effects of the first all-female transantarctic expedition on hormonal axes pertinent to reproductive and metabolic function., Methods: Six females (age, 28-36 yr; body mass index, 24.2 ± 0.97 kg·m) hauled 80-kg sledges 1700 km in 61 d. Estimated average energy intake was 20.8 ± 0.1 MJ·d (4970 ± 25 kcal·d). Whole and regional body composition was measured by dual-energy x-ray absorptiometry 1 and 2 months before and 15 d after, the expedition. Body fat was also estimated by skinfold and bioimpedance immediately before and after the expedition. Basal metabolic and endocrine blood markers and, after 0.25 mg dexamethasone suppression, 1-h 10-μg gonadorelin and 1.0 μg adrenocortiocotrophin-(1-24) tests were completed, 39-38 d preexpedition and 4 to 5 d and 15 to 16 d postexpedition. Cortisol was assessed in hair (monthly average concentrations) and saliva (five-point day curves and two-point diurnal sampling)., Results: Average body mass loss was 9.37 ± 2.31 kg (P < 0.0001), comprising fat mass only; total lean mass was maintained. Basal sex steroids, corticosteroids, and metabolic markers were largely unaffected by the expedition except leptin, which decreased during the expedition and recovered after 15 d, a proportionately greater change than body fat. Luteinizing hormone reactivity was suppressed before and during the expedition, but recovered after 15 d, whereas follicle-stimulating hormone did not change during or after the expedition. Cortisol reactivity did not change during or after the expedition. Basal (suppressed) cortisol was 73.25 ± 45.23 mmol·L before, 61.66 ± 33.11 mmol·L 5 d postexpedition and 54.43 ± 28.60 mmol·L 16 d postexpedition (P = 0.7). Hair cortisol was elevated during the expedition., Conclusions: Maintenance of reproductive and hypothalamic-pituitary-adrenal axis function in women after an extreme physical endeavor, despite energy deficiency, suggests high female biological capacity for extreme endurance exercise.

Increasing evidence supports fetal glucocorticoid exposure with associated altered offspring hypothalamic-pituitary-adrenal (HPA) axis activity as a key mechanism linking early life events with later life disease. Alterations in HPA axis activity are linked to a range of cardiometabolic and psychiatric diseases. As many of these diseases manifest sex differences in presentation we review the evidence for programmed sex-differences in the HPA axis. Available literature suggests vulnerability of the female HPA axis to prenatal stressors with female offspring demonstrating increased HPA axis reactivity. This may be due to changes in placental glucocorticoid metabolism leading to increased fetal glucocorticoid exposure. We discuss the potential consequences of increased vulnerability of the female HPA axis for later life health and consider the underlying mechanisms. Further studies are needed to determine whether sex-differences in early-life programming of the HPA axis represent a pathway underpinning the sex-differences in common cardiometabolic and psychiatric diseases., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Introduction: Evidence from civilian athletes raises the question of whether reproductive dysfunction may be seen in female soldiers as a result of military training. Such reproductive dysfunction consists of impaired ovulation with or without long-term subfertility., Methods: A critical review of pertinent evidence following an extensive literature search., Results: The evidence points towards reduced energy availability as the most likely explanation for exercise-induced reproductive dysfunction. Evidence also suggests that reproductive dysfunction is mediated by activation of the hypothalamic-pituitary-adrenal axis and suppression of the hypothalamic-pituitary-gonadal axis, with elevated ghrelin and reduced leptin likely to play an important role. The observed reproductive dysfunction exists as part of a female athletic triad, together with osteopenia and disordered eating. If this phenomenon was shown to exist with UK military training, this would be of significant concern. We hypothesise that the nature of military training and possibly field exercises may contribute to greater risk of reproductive dysfunction among female military trainees compared with exercising civilian controls. We discuss the features of military training and its participants, such as energy availability, age at recruitment, body phenotype, type of physical training, psychogenic stressors, altered sleep pattern and elemental exposure as contributors to reproductive dysfunction., Conclusions: We identify lines of future research to more fully characterise reproductive dysfunction in military women and suggest possible interventions that, if indicated, could improve their future well-being., Competing Interests: Competing interests: The authors are engaged in planning a prospective study of female endocrine response to UK military training as part of and funded by the UK Defence Women in Ground Close Combat Research Programme., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Fetal glucocorticoid overexposure is a key mechanism linking early development with later-life disease. In humans, low birth weight associates with increased fasting cortisol, hypothalamic-pituitary-adrenal (HPA) axis reactivity, and with cardiovascular risk and cognitive decline. As there are sex differences in these adult diseases, we hypothesized that there may be sex differences in programming of the HPA axis in response to prenatal stressors. We conducted a systematic review following Meta-Analysis of Observational Studies in Epidemiology and Preferred Reporting Items for Systematic Reviews and Meta-Analysis. We searched Embase, MEDLINE and Web of Science from inception to 31 October 2016. We included studies related to sex differences, prenatal exposures and HPA axis. We excluded studies investigating specific disease states. The 23 included studies investigated the consequences of low birth weight, preterm birth and maternal stressors of asthma, psychosocial stress and glucocorticoid medications on HPA axis outcomes of placental glucocorticoid biology and offspring HPA axis function in early life and later life. Female offspring exposed to stressors had increased HPA axis reactivity compared with males. Furthermore, the female placenta increased its permeability to maternal glucocorticoids following maternal stress with changes in the expression of 11β-hydroxysteroid dehydrogenase enzymes in response to maternal glucocorticoid exposure or asthma. Among males there was some evidence of altered diurnal cortisol secretion. We conclude that although there is some evidence of male vulnerability leading to altered diurnal cortisol secretion, the female HPA axis is more vulnerable to programming, particularly in terms of its reactivity; this suggests a mechanism underlying sex differences in later-life diseases.

Earlier puberty, especially in girls, is associated with physical and mental disorders. Prenatal glucocorticoid exposure influences the timing of puberty in animal models, but the human relevance of those findings is unknown. We studied whether voluntary consumption of licorice, which contains glycyrrhizin (a potent inhibitor of placental 11β-hydroxysteroid dehydrogenase type 2, the "barrier" to maternal glucocorticoids), by pregnant women was associated with pubertal maturation (height, weight, body mass index for age, difference between current and expected adult height, Tanner staging, score on the Pubertal Development Scale), neuroendocrine function (diurnal salivary cortisol, dexamethasone suppression), cognition (neuropsychological tests), and psychiatric problems (as measured by the Child Behavior Checklist) in their offspring. The children were born in 1998 in Helsinki, Finland, and examined during 2009-2011 (mean age = 12.5 (standard deviation (SD), 0.4) years; n = 378). Girls exposed to high maternal glycyrrhizin consumption (≥500 mg/week) were taller (mean difference (MD) = 0.4 SD, 95% confidence interval (CI): 0.1, 0.8), were heavier (MD = 0.6 SD, 95% CI: 0.2, 1.9), and had higher body mass index for age (MD = 0.6 SD, 95% CI: 0.2, 0.9). They were also 0.5 standard deviations (95% CI: 0.2, 0.8) closer to adult height and reported more advanced pubertal development (P < 0.04). Girls and boys exposed to high maternal glycyrrhizin consumption scored 7 (95% CI: 3.1, 11.2) points lower on tests of intelligence quotient, had poorer memory (P < 0.04), and had 3.3-fold (95% CI: 1.4, 7.7) higher odds of attention deficit/hyperactivity disorder problems compared with children whose mothers consumed little to no glycyrrhizin (≤249 mg/week). No differences in cortisol levels were found. Licorice consumption during pregnancy may be associated with harm for the developing offspring., (© The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The early life environment is a crucial time for establishing the trajectory of future health. Low birthweight is considered a marker of an adverse in utero environment and predisposes to cardio-metabolic disease later in life. It has been proposed that this is mediated by glucocorticoids, with life-long activation of the HPA axis. Here we review the evidence to support this hypothesis, with particular emphasis on the effects of fetal growth and nutrient stresses in utero on steroid pathways of the HPA axis. A better understanding of the mechanisms underlying these processes could help to optimize in utero health, and identify individuals at greatest risk of future disease., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: The maternal hypothalamic-pituitary-adrenal-axis (HPAA) undergoes dramatic activation during pregnancy. Increased cortisol and corticotrophin-releasing-hormone (CRH) associate with low birthweight and preterm labor. In non-pregnant obesity, the HPAA is activated but circulating cortisol levels are normal or lower than in lean women. We hypothesized that maternal cortisol levels would be lower in obese pregnancy, and would associate with increased fetal size and length of gestation., Method: Fasting serum cortisol was measured at 16, 28 and 36 weeks gestation and at 3-6 months postpartum in 276 severely obese and 135 lean women. In a subset of obese (n=20) and lean (n=20) we measured CRH, hormones that regulate bioavailable cortisol (corticosteroid-binding-globulin, estradiol, estriol, and progesterone). Urinary glucocorticoid metabolites were measured in pregnant (obese n=6, lean n=5) and non-pregnant (obese n=7, lean n=7) subjects., Results: Maternal cortisol and HPAA hormones were lower in obese pregnancy. Total urinary glucocorticoid metabolites increased significantly in lean pregnancy, but not in obese. Lower maternal cortisol in obese tended to be associated with increased birthweight (r=-0.13, p=0.066). In obese, CRH at 28 weeks correlated inversely with gestational length (r=-0.49, p=0.04), and independently predicted gestational length after adjustment for confounding factors (mean decrease in CRH of -0.25 pmol/L (95% CI -0.45 to -0.043 pmol/L) per/day increase in gestation)., Conclusion: In obese pregnancy, lower maternal cortisol without an increase in urinary glucocorticoid clearance may indicate a lesser activation of the HPAA than in lean pregnancy. This may offer a novel mechanism underlying increased birthweight and longer gestation in obese pregnancy., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Little is known about the associations between physical activity (PA) and hypothalamic-pituitary-adrenocortical axis (HPAA) activity in adolescents. This knowledge could offer insight into the links between PA and well-being in youth. We studied whether objectively-measured PA is associated with diurnal salivary cortisol responses and morning salivary cortisol responses after a low-dose overnight dexamethasone suppression test (DST) in adolescent girls and boys. We conducted a cross-sectional birth cohort study in Helsinki, Finland. At a mean age of 12.4 (SD=0.5) years, 150 girls and 133 boys wore wrist-worn accelerometers over at least 4 days to measure PA. Their salivary cortisol was measured across 1 day and upon awakening after a low-dose overnight DST (3 μg/kg of weight). Girls with higher overall PA and vigorous PA (VPA), and less sedentary time had lower salivary cortisol upon awakening and/or after (decreases between |0.17| and |0.25| SDs per SD increase in overall PA, VPA and decrease in sedentary time; P-values<0.039). Boys with higher overall PA, and less sedentary time had greater suppression of salivary cortisol following overnight DST (suppression between |0.24| and |0.27| SDs per SD increase in overall PA and decrease in sedentary time; P-values<0.012). Overall PA, VPA and sedentary time did not associate with DST suppression in girls or with diurnal salivary cortisol in boys. These results show that PA is associated with altered HPAA function in early adolescents, and that the associations are sex specific., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

An unhealthy lifestyle is thought to contribute to the metabolic syndrome in subjects with psychoses. In the present study we aimed to study whether life stress or cortisol measures may influence dietary patterns in subjects with early stages of psychoses. We studied 81 subjects with early psychoses (65 subjects with a psychotic disorder [PD] and <5 years of illness; 16 subjects at risk for psychosis [high-risk, HR]) and a control group of 25 healthy subjects (HS). Dietary habits were examined by a dietician, who registered food intake (24h recall). Physical activity was assessed by validated questionnaire. Life stress was assessed with Holmes-Rahe Social Readjustment Scale. Fasting morning salivary and plasma cortisol levels were determined. We found that PD and HR reported an unhealthier lifestyle with more smoking, reduced physical activity and poorer dietary habits. HR reported increased intake of calories and saturated fatty acids and reduced protein consumption, when compared to HS. Life stress was a predictor of these adverse behaviours, although we found opposite associations in HR and PD. Life stress was associated with increased intake of refined sugar in PD and decreased intake in HR and HS. Salivary cortisol was related to increased intake of saturated fat only in HR subjects, but cortisol levels in plasma or saliva were not associated with other dietary habits or obesity measures (BMI, waist circumference). Our study suggests that unhealthy diet in early psychoses is influenced by stress, but our data do not support this effect being mediated by hypercortisolism. Future preventive interventions in psychosis may target dietary habits, particularly for those who are at risk for psychosis., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Fetal glucocorticoid overexposure is a key potential mechanism underlying the link between low birthweight and later life diseases. The fetus is protected from high maternal glucocorticoid levels by the placental enzyme 11β-hydroxysteroid dehydrogenase type 2. Antenatal glucocorticoid administration to women at threat of preterm labor, and high endogenous maternal glucocorticoid levels during pregnancy associate with lower birthweight. Long-term consequences for offspring include hypothalamic-pituitary-adrenal axis activation, increased metabolic and cardiovascular disorders, and neurodevelopmental sequelae. Strategies are needed to limit antenatal glucocorticoid use to those most at risk of preterm labor and to identify those most at risk of future disease.

Dysfunctional regulation of the hypothalamic-pituitary-adrenal (HPA) axis has been proposed as an important biological mechanism underlying stress-related diseases; however, a better understanding of the interlinked neuroendocrine events driving the release of cortisol by this stress axis is essential for progress in preventing or halting irreversible development of adverse HPA-function. We aimed to investigate basal HPA-activity in a normal population in late adolescence, the time of life believed to overlap with HPA-axis maturation and establishment of a lasting set point level of HPA function. A total of 1258 participants (mean age 16.6 years) recruited from the Western Australian Pregnancy (Raine) Cohort provided fasting morning blood and saliva samples for basal HPA activity assessment. Irrespective of gender, linear regression modelling identified a positive correlation between the main components of the HPA-cascade of events, ACTH, total cortisol and free cortisol in saliva. Corticosteroid binding globulin (CBG) was inversely associated with free cortisol in saliva, an effect most clearly observed in boys. ACTH levels were lower, but cortisol levels were higher in girls than in boys. Girls may also be exposed to more bioactive cortisol, based on higher average free cortisol measured in saliva at awakening. These relatively higher female free cortisol levels were significantly reduced by oral contraceptive use, eliminating the gender specific difference in salivary cortisol. Free plasma cortisol, calculated from total circulating cortisol and CBG concentrations, was also significantly reduced in girls using oral contraceptives, possibly via an enhancing effect of oral contraceptives on blood CBG content. This study highlights a clear gender difference in HPA activity under non-stressful natural conditions. This finding may be relevant for research into sex-specific stress-related diseases with a typical onset in late adolescence., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Low birthweight, a marker of an adverse in utero environment, is associated with cardiometabolic disease and brain disorders in adulthood. The adaptive changes made by the fetus in response to the intra-uterine environment result in permanent changes in physiology, structure and metabolism, a phenomenon termed early life programming. One of the key hypotheses to explain programming, namely over exposure of the developing fetus to glucocorticoids, was proposed nearly two decades ago, following the observation that the fetus was protected from high glucocorticoid levels in the mother by the actions of the placental barrier enzyme, 11β-hydroxysteroid dehydrogenase, which converts active glucocorticoids into inactive products. Numerous mechanistic studies in animal models have been carried out to test this hypothesis using manipulations to increase maternal glucocorticoids. Overall, these have resulted in offspring of lower birthweight, with an activated hypothalamic-pituitary-adrenal (HPA) axis and an adverse metabolic profile and behavioural phenotype in adulthood. Altered glucocorticoid activity or action is a good candidate mechanism in humans to link low birthweight with cardiometabolic and brain disorders. We have carried out detailed studies in men and women showing that high levels of endogenous glucocorticoids, or treatment with exogenous glucocorticoids, is associated with an adverse metabolic profile, increased cardiovascular disease and altered mood and cognitive decline. Our laboratory carried out the first translational studies in humans to test the glucocorticoid hypothesis, firstly demonstrating in studies of adult men and women, that low birthweight was associated with high fasting cortisol levels. We went on to dissect the mechanisms underlying the high fasting cortisol, demonstrating activation of the HPA axis, with increased cortisol responses to stimulation with exogenous adrenocorticotrophin hormone, lack of habituation to the stress of venepuncture, and increased cortisol responses to psychosocial stress. We have developed new dynamic tests to dissect the mechanisms regulating HPA axis central negative feedback sensitivity in humans, and demonstrated that this may be altered in obesity, one component of the metabolic syndrome. There are now studies in humans demonstrating that high circulating levels of maternal cortisol during pregnancy correlate negatively with birthweight, suggesting that excess glucocorticoids can by-pass the placental barrier. Deficiencies in the barrier enzyme, potentially increasing fetal glucocorticoid exposure, can also arise in association with maternal stress, malnutrition and disease, and can be inhibited by consumption of liquorice, which contains glycyrrhizin, an HSD inhibitor. Importantly, studies in humans have now demonstrated that high maternal cortisol in pregnancy and/or inhibition of HSD2 are associated with programmed outcomes in childhood including higher blood pressure, behavioural disorders as well as altered brain structure. We are investigating this further, using novel magnetic resonance imaging techniques to study the developing fetal brain in utero. The translational studies in support of the glucocorticoid hypothesis, and demonstrating that glucocorticoids are both mediators and targets of programming, are exciting and raise the question of whether this information can be used to identify those individuals most at risk of later life disease. In a recent study we showed that alterations in DNA methylation at genes important in regulating cortisol levels, tissue glucocorticoid action, blood pressure and fetal growth, are present in adulthood in association with both early life parameters and cardiometabolic risk factors. These preliminary data add to the limited literature in humans indicating a persisting epigenetic link between early life events and subsequent disease risk. Such findings open novel avenues for further exploration of the contribution of glucocorticoids to later life disease., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Overexposure of the developing fetus to glucocorticoids is hypothesised to be one of the key mechanisms linking early life development with later life disease. The maternal hypothalamic-pituitary-adrenal (HPA) axis undergoes dramatic changes during pregnancy and postpartum. Although cortisol levels rise threefold by the third trimester, the fetus is partially protected from high cortisol by activity of the enzyme 11β-hydroxysteroid dehydrogenase type 2 (HSD11B2). Maternal HPA axis activity and activity of HSD11B2 may be modified by maternal stress and disease allowing greater transfer of glucocorticoids from mother to fetus. Here we review emerging data from human studies linking dysregulation of the maternal HPA axis to outcomes in both the mother and her offspring. For the offspring, greater glucocorticoid exposure is associated with lower birth weight and shorter gestation at delivery. In addition, evidence supports longer term consequences for the offspring including re-setting of the HPA axis and susceptibility to neurodevelopmental problems and cardiometabolic disease. For the mother, the changes in the HPA axis, particularly in the postpartum period, may increase vulnerability to mood disturbances. Further understanding of the changes in the HPA axis during pregnancy and the impact of these changes may ultimately allow early identification of those most at risk of future disease., (Copyright © 2013 S. Karger AG, Basel.)

Epidemiological studies have shown that low birthweight is associated with increased risk of development of diabetes and obesity in later life. Over-exposure of the developing fetus to glucocorticoids is one of the major hypotheses that has been proposed to explain this association. In animal models, a range of manipulations that increase fetal glucocorticoid load, 'programme' permanent changes in glucose and insulin metabolism and adiposity. This may be mediated by alterations in regulation of the hypothalamic-pituitary-adrenal (HPA) axis. In humans, low birthweight is associated with increased circulating glucocorticoid levels, and an increased cortisol response to physiological and psychosocial stressors, in child- and adulthood. This activation of the HPA axis is also associated with increased risk of development of diabetes and obesity in later life., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Background & Aims: Suppression of the hypothalamic-pituitary-adrenal axis occurs in cirrhosis and cholestasis and is associated with increased concentrations of bile acids. We investigated whether this was mediated through bile acids acting to impair steroid clearance by inhibiting glucocorticoid metabolism by 5beta-reductase., Methods: The effect of bile acids on glucocorticoid metabolism was studied in vitro in hepatic subcellular fractions and hepatoma cells, allowing quantitation of the kinetics and transcript abundance of 5beta-reductase. Metabolism was subsequently examined in vivo in rats following dietary manipulation or bile duct ligation. Finally, glucocorticoid metabolism was assessed in humans with obstructive jaundice., Results: In rat hepatic cytosol, chenodeoxycholic acid competitively inhibited 5beta-reductase (K(i) 9.19+/-0.40 microM) and reduced its transcript abundance (in H4iiE cells) and promoter activity (reporter system, HepG2 cells). In Wistar rats, dietary chenodeoxycholic acid (1% w/w chow) inhibited hepatic 5beta-reductase activity, reduced urinary excretion of 3alpha,5beta-tetrahydrocorticosterone and reduced adrenal weight. Conversely, a fat-free diet suppressed bile acid levels and increased hepatic 5beta-reductase activity, supplementation of the fat-free diet with CDCA reduced 5beta-reductase activity, and urinary 3alpha,5beta-reduced corticosterone. Cholestasis in rats suppressed hepatic 5beta-reductase activity and transcript abundance. In eight women with obstructive jaundice, relative urinary excretion of 3alpha,5beta-tetrahydrocortisol was significantly lower than in healthy controls., Conclusion: These data suggest a novel role for bile acids in inhibiting hepatic glucocorticoid clearance, of sufficient magnitude to suppress hypothalamic-pituitary-adrenal axis activity. Elevated hepatic bile acids may account for adrenal insufficiency in liver disease., (Crown Copyright (c) 2010. Published by Elsevier B.V. All rights reserved.)

Context: Hypothalamic-pituitary-adrenal (HPA) axis dysregulation may underlie disorders including obesity, depression, cognitive decline, and the metabolic syndrome. Conventional tests of HPA axis negative feedback rely on glucocorticoid receptor (GR) agonists such as dexamethasone but do not test feedback by endogenous cortisol, potentially mediated by both GR and mineralocorticoid receptors (MR)., Objective: The objective of the study was to use a combination of GR (RU38486, mifepristone) and MR (spironolactone) antagonists to explore the poorly understood activation of the HPA axis that occurs in obesity., Design: This was a double-blind, placebo-controlled, randomized, crossover study., Setting: The study was conducted at a clinical research facility., Participants: Participants included 15 lean (body mass index 22.0 +/- 1.6 kg/m(2)) and 16 overweight/obese (body mass index 30.1 +/- 3.5 kg/m(2)) men., Intervention: Subjects attended on four occasions for blood and saliva sampling every 30 min between 1800 and 2200 h. At 1100 and 1600 h before visits, subjects took 200 mg spironolactone, 400 mg RU38486, 200 mg spironolactone + 400 mg RU38486, or placebo orally., Main Outcome Measures: Serum cortisol levels after drug or placebo were measured., Results: Cortisol levels did not differ between lean and obese after placebo. Spironolactone and RU38486 alone had modest effects, increasing cortisol by less than 50% in both groups. However, combined spironolactone plus RU38486 elevated cortisol concentrations substantially, more so in lean than obese men [2.9- (0.3) vs. 2.2 (0.3)-fold elevation, P = 0.002]., Conclusions: Combined receptor antagonist stimulation of the HPA axis reveals redundancy of MR and GR in negative feedback in humans. Obese men have impaired responses to combined receptor antagonist stimulation, suggesting impaired negative feedback by endogenous cortisol. Such an approach may be useful to dissect abnormal HPA axis control in neuropsychiatric and other disorders.

Objective: Assessing the integrity of the hypothalamic-pituitary-adrenal (HPA) axis following pituitary surgery is necessary to determine the requirement for glucocorticoid replacement therapy, but there remains controversy about the optimum way to measure this., Design and Measurements: Postal questionnaire survey among UK endocrinologists to evaluate the current methods used., Results: The response rate was low (81 out of 598 questionnaires mailed), although 85% were consultants. Fifty-five percent measured 9:00 h plasma cortisol in the immediate postoperative phase. Most carried out definitive testing between 4 and 12 weeks: 36% routinely used the insulin tolerance test (ITT), 59% used the short synacthen test (SST). The 30-min cortisol value was used by 67% as a 'pass' when interpreting the results. Others included cortisol measurement at 60 min (17%) or incremental value (7%). For long-term follow-up of patients not rendered ACTH-deficient by surgery, 64% used the SST for patients who had received radiotherapy. If patients had not had radiotherapy, 42% used the SST, whereas 33% did no routine testing unless the patient was symptomatic or there was evidence of tumour recurrence on imaging. If patients were symptomless but 'failed' the chosen test, 28% still treated the patient with glucocorticoid replacement, 38% retested before treatment and 24% recommended glucocorticoid cover for when unwell or 'stressed'. Fifty-six percent used hydrocortisone at doses of 20 mg/day as replacement therapy., Conclusion: Thus, assessment of the HPA axis remains controversial. Although the SST is becoming more popular, there is still considerable variation in the interpretation of results and, in particular, the decision of whether or not to treat with lifelong glucocorticoid replacement therapy.

Although excessive glucocorticoids are a well-recognized cause of osteoporosis, little is known about the role of endogenous glucocorticoids in determining skeletal mass. We have performed a detailed study of the hypothalamic-pituitary-adrenal (HPA) axis to explore the relationships between cortisol secretion and adult bone mass in 151 healthy men and 96 healthy women aged 61 to 73 years. At baseline and 4-year follow-up, bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) at the lumbar spine and proximal femur; a lifestyle questionnaire was completed; and height, weight, and waist and hip circumferences were measured. At follow-up subjects underwent a very low-dose (0.25 mg) dexamethasone suppression test, a low-dose (1 microg) short synacthen test, and a 24-hour urine collection for measurement of cortisol and its metabolites. In men, elevated peak plasma cortisol was associated with accelerated loss of mineral density in the lumbar spine (r = 0.16, P = 0.05). This relationship remained significant after adjustment for testosterone, estradiol, 25-hydroxyvitamin D, and parathyroid hormone levels (r = 0.22, P = 0.01) and after additional adjustment for age, (BM), activity, cigarette and alcohol consumption, and Kellgren/Lawrence score (r = 0.19, P = 0.03). In contrast in women, elevated peak plasma cortisol was associated with lower baseline BMD at the femoral neck (r = -0.23, P = 0.03) and greater femoral neck loss rate (r = 0.24, P = 0.02). There was no association between plasma cortisol concentrations after dexamethasone or urinary total cortisol metabolite excretion and bone density or bone loss rate at any site. These data provide evidence that circulating endogenous glucocorticoids influence the rate of involutional bone loss in healthy individuals.

Objective: Increased hypothalamic-pituitary-adrenal (HPA) axis activity in men of low birthweight may be an important link between early life and the adult metabolic syndrome. In animal models females are more sensitive than males to HPA axis programming, but whether gender influences susceptibility in humans is unknown., Design: Birth cohort study., Methods: We studied 106 women aged 67-78 years, from Hertfordshire, UK, in whom birthweight was recorded. Negative feedback sensitivity was assessed by an overnight low-dose (0.25 mg) dexa-methasone suppression test, and adrenal sensitivity by a low-dose (1 microg) ACTH(1 - 24) stimulation test. Cortisol and its metabolites were analysed in a 24 h urine collection. Data were compared with previously published identical measurements in 205 men aged 66-77 years from the same cohort., Results: In women, plasma cortisol levels after dexamethasone were lower (P < 0.0001) and peak cortisol following ACTH(1 - 24) were higher (P < 0.0001) than in men, suggesting a more responsive HPA axis. As in men, women with lower birthweight had enhanced plasma cortisol responses to ACTH(1 - 24) (P = 0.05 for trend) but no difference in plasma cortisol after dexamethasone or in urinary cortisol metabolite excretion. The strength of the association in women was not different from that in men; a 1 lb decrease in birthweight was associated with an incremental rise in cortisol of 12.6 nmol/l (95% confidence interval (CI) 1.4, 23.8) in men, P = 0.03, and 14.8 nmol/l (95% CI -0.4, 29.9) in women, P = 0.05 (P = 0.82 for birthweight x gender interaction). In a combined analysis of men and women adjusted for gender (n = 302), a 1 lb decrease in birthweight was associated with a 13.4 nmol/l (95% CI 4.5, 22.4) greater incremental rise in plasma cortisol, P = 0.003., Conclusions: Associations between lower birthweight and increased HPA axis activity are similar in men and women, supporting the hypothesis that HPA axis activation is an important mechanism underlying programming of adult disease.