Contribution of local regeneration of glucocorticoids to tissue steroid pools

11β-Hydroxysteroid dehydrogenase 1 (11βHSD1) is a drug target to attenuate adverse effects of chronic glucocorticoid excess. It catalyses intracellular regeneration of active glucocorticoids in tissues including brain, liver and adipose tissue (coupled to hexose-6-phosphate dehydrogenase, H6PDH). 11βHSD1 activity in individual tissues is thought to contribute significantly to glucocorticoid levels at those sites, but its local contribution vs glucocorticoid delivery via the circulation is unknown. Here, we hypothesised that hepatic 11βHSD1 would contribute significantly to the circulating pool. This was studied in mice with Cre-mediated disruption of Hsd11b1 in liver (Alac-Cre) vs adipose tissue (aP2-Cre) or whole-body disruption of H6pdh. Regeneration of [9,12,12-2H3]-cortisol (d3F) from [9,12,12-2H3]-cortisone (d3E), measuring 11βHSD1 reductase activity was assessed at steady state following infusion of [9,11,12,12-2H4]-cortisol (d4F) in male mice. Concentrations of steroids in plasma and amounts in liver, adipose tissue and brain were measured using mass spectrometry interfaced with matrix-assisted laser desorption ionisation or liquid chromatography. Amounts of d3F were higher in liver, compared with brain and adipose tissue. Rates of appearance of d3F were ~6-fold slower in H6pdh-/- mice, showing the importance for whole-body 11βHSD1 reductase activity. Disruption of liver 11βHSD1 reduced the amounts of d3F in liver (by ~36%), without changes elsewhere. In contrast disruption of 11βHSD1 in adipose tissue reduced rates of appearance of circulating d3F (by ~67%) and also reduced regenerated of d3F in liver and brain (both by ~30%). Thus, the contribution of hepatic 11βHSD1 to circulating glucocorticoid levels and amounts in other tissues is less than that of adipose tissue.

11β-Hydroxysteroid dehydrogenase 1 deficiency prevents PTSD-like memory in young adult mice

Post-traumatic stress disorder (PTSD) is characterized by the co-existence of a persistent strong memory of the traumatic experience and amnesia for the peritraumatic context. Most animal models, however, fail to account for the contextual amnesia which is considered to play a critical role in the etiology of PTSD intrusive memories. It is also unclear how aging affects PTSD-like memory. Glucocorticoids alter the formation and retention of fear-associated memory. Here, we investigated whether a deficiency of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) (an intracellular glucocorticoid generating enzyme) and aging modulates fear conditioning and PTSD-like memory in mice. We first measured memory in 6 months and 24 months old 11β-HSD1 deficient (HSD1 KO) and wildtype (WT) mice following paired tone-shock fear conditioning. Then, separate groups of mice were exposed to restraint stress immediately after unpaired tone-shock contextual fear conditioning. Compared with young controls, aged WT mice exhibited enhanced auditory cued fear memory, but contextual fear memory was not different. Contextual fear memory retention was attenuated in both young and aged HSD1 KO mice. In contrast, auditory cued fear memory was reduced 24 h after training only in aged HSD1 KO mice. When fear conditioned with stress, WT mice displayed PTSD-like memory (i.e., increased fear to tone not predictive of shock and reduced fear to 'aversive' conditioning context); this was unchanged with aging. In contrast, young HSD1 KO mice fear conditioned with stress showed normal fear memory (i.e., increased fear response to conditioning context), as observed in WT mice fear conditioned alone. While aged HSD1 KO mice fear conditioned with stress also displayed normal contextual fear memory, the fear response to the 'safe' tone remained. Thus, a deficiency of 11β-HSD1 protects against both amnesia for the conditioning context and hypermnesia for a salient tone in young adult mice but only contextual amnesia is prevented in aged mice. These results suggest that brain 11β-HSD1 generated glucocorticoids make a significant contribution to fear conditioning and PTSD-like memory. 11β-HSD1 inhibition may be useful in prevention and/or treatment of PTSD.

Cohort profile for the STratifying Resilience and Depression Longitudinally (STRADL) study: A depression-focused investigation of Generation Scotland, using detailed clinical, cognitive, and neuroimaging assessments

STratifying Resilience and Depression Longitudinally (STRADL) is a population-based study built on the Generation Scotland: Scottish Family Health Study (GS:SFHS) resource. The aim of STRADL is to subtype major depressive disorder (MDD) on the basis of its aetiology, using detailed clinical, cognitive, and brain imaging assessments. The GS:SFHS provides an important opportunity to study complex gene-environment interactions, incorporating linkage to existing datasets and inclusion of early-life variables for two longitudinal birth cohorts. Specifically, data collection in STRADL included: socio-economic and lifestyle variables; physical measures; questionnaire data that assesses resilience, early-life adversity, personality, psychological health, and lifetime history of mood disorder; laboratory samples; cognitive tests; and brain magnetic resonance imaging. Some of the questionnaire and cognitive data were first assessed at the GS:SFHS baseline assessment between 2006-2011, thus providing longitudinal measures relevant to the study of depression, psychological resilience, and cognition. In addition, routinely collected historic NHS data and early-life variables are linked to STRADL data, further providing opportunities for longitudinal analysis. Recruitment has been completed and we consented and tested 1,188 participants.

Hair glucocorticoids are associated with childhood adversity, depressive symptoms and reduced global and lobar grey matter in Generation Scotland

Hypothalamic-pituitary-adrenal (HPA) axis dysregulation has been commonly reported in major depressive disorder (MDD), but with considerable heterogeneity of results; potentially due to the predominant use of acute measures of an inherently variable/phasic system. Chronic longer-term measures of HPA-axis activity have yet to be systematically examined in MDD, particularly in relation to brain phenotypes, and in the context of early-life/contemporaneous stress. Here, we utilise a temporally stable measure of cumulative HPA-axis function (hair glucocorticoids) to investigate associations between cortisol, cortisone and total glucocorticoids with concurrent measures of (i) lifetime-MDD case/control status and current symptom severity, (ii) early/current-life stress and (iii) structural neuroimaging phenotypes, in N = 993 individuals from Generation Scotland (mean age = 59.1 yrs). Increased levels of hair cortisol were significantly associated with reduced global and lobar brain volumes with reductions in the frontal, temporal and cingulate regions (βrange = -0.057 to -0.104, all PFDR < 0.05). Increased levels of hair cortisone were significantly associated with MDD (lifetime-MDD status, current symptoms, and severity; βrange = 0.071 to 0.115, all PFDR = < 0.05), with early-life adversity (β = 0.083, P = 0.017), and with reduced global and regional brain volumes (global: β = -0.059, P = 0.043; nucleus accumbens: β = -0.075, PFDR = 0.044). Associations with total glucocorticoids followed a similar pattern to the cortisol findings. In this large community-based sample, elevated glucocorticoids were significantly associated with MDD, with early, but not later-life stress, and with reduced global and regional brain phenotypes. These findings provide important foundations for future mechanistic studies to formally explore causal relationships between early adversity, chronic rather than acute measures of glucocorticoids, and neurobiological associations relevant to the aetiology of MDD.

Cohort profile for the STratifying Resilience and Depression Longitudinally (STRADL) study: A depression-focused investigation of Generation Scotland, using detailed clinical, cognitive, and neuroimaging assessments

STratifying Resilience and Depression Longitudinally (STRADL) is a population-based study built on the Generation Scotland: Scottish Family Health Study (GS:SFHS) resource. The aim of STRADL is to subtype major depressive disorder (MDD) on the basis of its aetiology, using detailed clinical, cognitive, and brain imaging assessments. The GS:SFHS provides an important opportunity to study complex gene-environment interactions, incorporating linkage to existing datasets and inclusion of early-life variables for two longitudinal birth cohorts. Specifically, data collection in STRADL included: socio-economic and lifestyle variables; physical measures; questionnaire data that assesses resilience, early-life adversity, personality, psychological health, and lifetime history of mood disorder; laboratory samples; cognitive tests; and brain magnetic resonance imaging. Some of the questionnaire and cognitive data were first assessed at the GS:SFHS baseline assessment between 2006-2011, thus providing longitudinal measures relevant to the study of depression, psychological resilience, and cognition. In addition, routinely collected historic NHS data and early-life variables are linked to STRADL data, further providing opportunities for longitudinal analysis. Recruitment has been completed and we consented and tested 1,188 participants.

Face coverings and respiratory tract droplet dispersion

Respiratory droplets are the primary transmission route for SARS-CoV-2, a principle which drives social distancing guidelines. Evidence suggests that virus transmission can be reduced by face coverings, but robust evidence for how mask usage might affect safe distancing parameters is lacking. Accordingly, we set out to quantify the effects of face coverings on respiratory tract droplet deposition. We tested an anatomically realistic manikin head which ejected fluorescent droplets of water and human volunteers, in speaking and coughing conditions without a face covering, or with a surgical mask or a single-layer cotton face covering. We quantified the number of droplets in flight using laser sheet illumination and UV-light for those that had landed at table height at up to 2 m. For human volunteers, expiratory droplets were caught on a microscope slide 5 cm from the mouth. Whether manikin or human, wearing a face covering decreased the number of projected droplets by less than 1000-fold. We estimated that a person standing 2 m from someone coughing without a mask is exposed to over 10 000 times more respiratory droplets than from someone standing 0.5 m away wearing a basic single-layer mask. Our results indicate that face coverings show consistent efficacy at blocking respiratory droplets and thus provide an opportunity to moderate social distancing policies. However, the methodologies we employed mostly detect larger (non-aerosol) sized droplets. If the aerosol transmission is later determined to be a significant driver of infection, then our findings may overestimate the effectiveness of face coverings.

Maternal Glucocorticoid Metabolism Across Pregnancy: A Potential Mechanism Underlying Fetal Glucocorticoid Exposure

CONTEXT

Across pregnancy, maternal serum cortisol levels increase up to 3-fold. It is not known whether maternal peripheral cortisol metabolism and clearance change across pregnancy or influence fetal cortisol exposure and development.

OBJECTIVES

The primary study objective was to compare maternal urinary glucocorticoid metabolites, as markers of cortisol metabolism and clearance, between the second and third trimester of pregnancy. Secondary objectives were to test associations of total maternal urinary glucocorticoid excretion, with maternal serum cortisol levels and offspring birth weight z score.

DESIGN, PARTICIPANTS, AND SETTING

A total of 151 women with singleton pregnancies, recruited from prenatal clinic at the Pittsburgh site of the Measurement of Maternal Stress (MOMS) study, had 24-hour urine collections during both the second and third trimesters.

RESULTS

Between the second and third trimester, total urinary glucocorticoid excretion increased (ratio of geometric means [RGM] 1.37, 95% CI 1.22-1.52, P < .001), and there was an increase in calculated 5β-reductase compared to 5α-reductase activity (RGM 3.41, 95% CI 3.04-3.83, P < .001). During the third trimester total urinary glucocorticoid excretion and serum cortisol were negatively correlated (r = -0.179, P = .029). Mean total urinary glucocorticoid excretion across both trimesters and offspring birth weight z score were positively associated (β = 0.314, P = .001).

CONCLUSIONS

The estimated activity of maternal enzymes responsible for cortisol metabolism change between the second and third trimester of pregnancy. Additionally, maternal peripheral metabolism and clearance of cortisol may serve as a novel mechanism affecting fetal cortisol exposure and growth.

Predictors of Nephrolithiasis, Osteoporosis, and Mortality in Primary Hyperparathyroidism

CONTEXT

Primary hyperparathyroidism (PHPT) has a prevalence of 0.86% and is associated with increased risk of nephrolithiasis and osteoporosis. PHPT may also be associated with increased risk of cardiovascular disease and mortality.

OBJECTIVE

To identify risk factors for nephrolithiasis, osteoporosis, and mortality in PHPT.

DESIGN

Retrospective cohort study.

SETTING

University teaching hospital.

PATIENTS

Presented with PHPT between 2006 and 2014 (n = 611).

MAIN OUTCOME MEASURE

Assessment of nephrolithiasis, osteoporosis, and mortality.

RESULTS

Of patients with PHPT, 13.9% had nephrolithiasis. Most had previously documented stone disease, and only 4.7% of asymptomatic patients who were screened for renal stones had calculi identified, not very dissimilar to the rate in the non-PHPT population. Younger age (P < 0.001) and male sex (P = 0.003) were the only independent predictors of nephrolithiasis. Of patients with dual-energy X-ray absorptiometry data, 48.4% had osteoporosis (223/461). Older age (P < 0.001), lower body mass index (P = 0.002), and lower creatinine (P = 0.006) were independently associated with a diagnosis of osteoporosis. Higher PTH was independently associated with lower z score at the hip (P = 0.009); otherwise, calcium and PTH were not associated with lower z scores. Mortality in PHPT was associated with older age (P < 0.008), social deprivation (P = 0.028), and adjusted calcium (P = 0.009) but not independently with PTH at diagnosis.

CONCLUSIONS

Screening for nephrolithiasis has a low yield, particularly in lower risk patients. Osteoporosis is only minimally associated with biochemical indices of PHPT. Mortality is associated with higher calcium (and possibly vitamin D deficiency) but not PTH.

Mining for Oxysterols in Cyp7b1-/- Mouse Brain and Plasma: Relevance to Spastic Paraplegia Type 5

Deficiency in cytochrome P450 (CYP) 7B1, also known as oxysterol 7α-hydroxylase, in humans leads to hereditary spastic paraplegia type 5 (SPG5) and in some cases in infants to liver disease. SPG5 is medically characterized by loss of motor neurons in the corticospinal tract. In an effort to gain a better understanding of the fundamental biochemistry of this disorder, we have extended our previous profiling of the oxysterol content of brain and plasma of Cyp7b1 knockout (-/-) mice to include, amongst other sterols, 25-hydroxylated cholesterol metabolites. Although brain cholesterol levels do not differ between wild-type (wt) and knockout mice, we find, using a charge-tagging methodology in combination with liquid chromatography-mass spectrometry (LC-MS) and multistage fragmentation (MSⁿ), that there is a build-up of the CYP7B1 substrate 25-hydroxycholesterol (25-HC) in Cyp7b1-/- mouse brain and plasma. As reported earlier, levels of (25R)26-hydroxycholesterol (26-HC), 3β-hydroxycholest-5-en-(25R)26-oic acid and 24S,25-epoxycholesterol (24S,25-EC) are similarly elevated in brain and plasma. Side-chain oxysterols including 25-HC, 26-HC and 24S,25-EC are known to bind to INSIG (insulin-induced gene) and inhibit the processing of SREBP-2 (sterol regulatory element-binding protein-2) to its active form as a master regulator of cholesterol biosynthesis. We suggest the concentration of cholesterol in brain of the Cyp7b1-/- mouse is maintained by balancing reduced metabolism, as a consequence of a loss in CYP7B1, with reduced biosynthesis. The Cyp7b1-/- mouse does not show a motor defect; whether the defect in humans is a consequence of less efficient homeostasis of cholesterol in brain has yet to be uncovered.

Predicting outcomes and complications following radioiodine therapy in Graves' thyrotoxicosis

OBJECTIVE

Radioiodine (RAI) is an effective treatment for Graves' thyrotoxicosis but is associated with a failure rate of 15% and may be a risk factor for thyroid eye disease (TED) and weight gain. We sought to examine predictors of RAI failure, weight gain, TED and patient satisfaction.

DESIGN

Retrospective cohort study.

PATIENTS

A total of 655 episodes of RAI in Graves' thyrotoxicosis patients (2006-2015).

MEASUREMENTS

Biochemical assessment, including TFTs and thyrotropin receptor antibodies (TRAb), clinical features (eg, TED, weight and thionamide use) and patient questionnaire.

RESULTS

The treatment failure rate was 17%. Failure was greater with higher fT4 (P = 0.002) and higher TRAb (P = 0.004). Failure rate was 42.2% when TRAb >40 U/L. Median weight gain was 3.2 kg in those with normal fT4 prior to RAI and 5.8 kg when fT4 was elevated (P < 0.001). New TED developed in 7.6% but was not associated with post-RAI dysthyroidism. Treatment satisfaction was generally high (median response 8/10).

CONCLUSIONS

Treatment failure after RAI occurs in predictable groups and this should be reflected in the information provided to patients. Weight gain is common and may not entirely be explained by a return to pre-thyrotoxic baseline. We were unable to detect any significant impact of post-RAI dysthyroidism on weight gain, TED or thyroid symptoms in this large cohort.

Presentation, diagnostic assessment and surgical outcomes in primary hyperparathyroidism: a single centre's experience

OBJECTIVE

Primary hyperparathyroidism (PHPT) is a common reason for referral to endocrinology but the evidence base guiding assessment is limited. We evaluated the clinical presentation, assessment and subsequent management in PHPT.

DESIGN

Retrospective cohort study.

PATIENTS

PHPT assessed between 2006 - 2014 (n = 611) in a university hospital.

MEASUREMENTS

Symptoms, clinical features, biochemistry, neck radiology and surgical outcomes.

RESULTS

Fatigue (23.8%), polyuria (15.6%) and polydipsia (14.9%) were associated with PHPT biochemistry. Bone fracture was present in 16.4% but was not associated with biochemistry. A history of nephrolithiasis (10.0%) was associated only with younger age (P = 0.006) and male gender (P = 0.037). Thiazide diuretic discontinuation was not associated with any subsequent change in calcium (P = 0.514). Urine calcium creatinine clearance ratio (CCCR) was <0.01 in 18.2% of patients with confirmed PHPT. Older age (P < 0.001) and lower PTH (P = 0.043) were associated with failure to locate an adenoma on ultrasound (44.0% of scans). When an adenoma was identified on ultrasound the lateralization was correct in 94.5%. Non-curative surgery occurred in 8.2% and was greater in those requiring more than one neck imaging modality (OR 2.42, P = 0.035).

CONCLUSIONS

Clinical features associated with PHPT are not strongly related to biochemistry. Thiazide cessation does not appear to attenuate hypercalcaemia. PHPT remains the likeliest diagnosis in the presence of low CCCR. Ultrasound is highly discriminant when an adenoma is identified but surgical failure is more likely when more than one imaging modality is required.

Midlife stress alters memory and mood-related behaviors in old age: Role of locally activated glucocorticoids

Chronic exposure to stress during midlife associates with subsequent age-related cognitive decline and may increase the vulnerability to develop psychiatric conditions. Increased hypothalamic-pituitary-adrenal (HPA) axis activity has been implicated in pathogenesis though any causative role for glucocorticoids is unestablished. This study investigated the contribution of local glucocorticoid regeneration by the intracellular enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), in persisting midlife stress-induced behavioral effects in mice. Middle-aged (10 months old) 11β-HSD1-deficient mice and wild-type congenic controls were randomly assigned to 28 days of chronic unpredictable stress or left undisturbed (non-stressed). All mice underwent behavioral testing at the end of the stress/non-stress period and again 6-7 months later. Chronic stress impaired spatial memory in middle-aged wild-type mice. The effects, involving a wide spectrum of behavioral modalities, persisted for 6-7 months after cessation of stress into early senescence. Enduring effects after midlife stress included impaired spatial memory, enhanced contextual fear memory, impaired fear extinction, heightened anxiety, depressive-like behavior, as well as reduced hippocampal glucocorticoid receptor mRNA expression. In contrast, 11β-HSD1 deficient mice resisted both immediate and enduring effects of chronic stress, despite similar stress-induced increases in systemic glucocorticoid activity during midlife stress. In conclusion, chronic stress in midlife exerts persisting effects leading to cognitive and affective dysfunction in old age via mechanisms that depend, at least in part, on brain glucocorticoids generated locally by 11β-HSD1. This finding supports selective 11β-HSD1 inhibition as a novel therapeutic target to ameliorate the long-term consequences of stress-related psychiatric disorders in midlife.

11β-hydroxysteroid dehydrogenase-1 deficiency alters brain energy metabolism in acute systemic inflammation

Chronically elevated glucocorticoid levels impair cognition and are pro-inflammatory in the brain. Deficiency or inhibition of 11β-hydroxysteroid dehydrogenase type-1 (11β-HSD1), which converts inactive into active glucocorticoids, protects against glucocorticoid-associated chronic stress- or age-related cognitive impairment. Here, we hypothesised that 11β-HSD1 deficiency attenuates the brain cytokine response to inflammation. Because inflammation is associated with altered energy metabolism, we also examined the effects of 11β-HSD1 deficiency upon hippocampal energy metabolism. Inflammation was induced in 11β-HSD1 deficient (Hsd11b1Del/Del) and C57BL/6 control mice by intraperitoneal injection of lipopolysaccharide (LPS). LPS reduced circulating neutrophil and monocyte numbers and increased plasma corticosterone levels equally in C57BL/6 and Hsd11b1Del/Del mice, suggesting a similar peripheral inflammatory response. However, the induction of pro-inflammatory cytokine mRNAs in the hippocampus was attenuated in Hsd11b1Del/Del mice. Principal component analysis of mRNA expression revealed a distinct metabolic response to LPS in hippocampus of Hsd11b1Del/Del mice. Expression of Pfkfb3 and Ldha, key contributors to the Warburg effect, showed greater induction in Hsd11b1Del/Del mice. Consistent with increased glycolytic flux, levels of 3-phosphoglyceraldehyde and dihydroxyacetone phosphate were reduced in hippocampus of LPS injected Hsd11b1Del/Del mice. Expression of Sdha and Sdhb, encoding subunits of succinate dehydrogenase/complex II that determines mitochondrial reserve respiratory capacity, was induced specifically in hippocampus of LPS injected Hsd11b1Del/Del mice, together with increased levels of its product, fumarate. These data suggest 11β-HSD1 deficiency attenuates the hippocampal pro-inflammatory response to LPS, associated with increased capacity for aerobic glycolysis and mitochondrial ATP generation. This may provide better metabolic support and be neuroprotective during systemic inflammation or aging.

Macrophage 11β-HSD-1 deficiency promotes inflammatory angiogenesis

11β-Hydroxysteroid dehydrogenase-1 (11β-HSD1) predominantly converts inert glucocorticoids into active forms, thereby contributing to intracellular glucocorticoid levels. 11β-HSD1 is dynamically regulated during inflammation, including in macrophages where it regulates phagocytic capacity. The resolution of inflammation in some disease models including inflammatory arthritis is impaired by 11β-HSD1 deficiency or inhibition. However, 11β-HSD1 deficiency/inhibition also promotes angiogenesis, which is beneficial in mouse models of surgical wound healing, myocardial infarction or obesity. The cell types responsible for the anti-inflammatory and anti-angiogenic roles of 11β-HSD1 have not been characterised. Here, we generated Hsd11b1^MKO mice with LysM-Cre mediated deletion of Hsd11b1 to investigate whether 11β-HSD1 deficiency in myeloid phagocytes is pro-angiogenic and/or affects the resolution of inflammation. Resolution of inflammatory K/BxN-induced arthritis was impaired in Hsd11b1^MKO mice to a similar extent as in mice globally deficient in 11β-HSD1. This was associated with >2-fold elevation in levels of the endothelial marker Cdh5 mRNA, suggesting increased angiogenesis in joints of Hsd11b1^MKO mice following arthritis. A pro-angiogenic phenotype was confirmed by measuring angiogenesis in subcutaneously implanted polyurethane sponges, in which Hsd11b1^MKO mice showed 20% greater vessel density than their littermate controls, associated with higher expression of Cdh5 Thus, 11β-HSD1 deficiency in myeloid phagocytes promotes angiogenesis. Targeting 11β-HSD1 in macrophages may be beneficial in tissue repair.

Overexpression of Mineralocorticoid Receptors in the Mouse Forebrain Partly Alleviates the Effects of Chronic Early Life Stress on Spatial Memory, Neurogenesis and Synaptic Function in the Dentate Gyrus

Evidence from human studies suggests that high expression of brain mineralocorticoid receptors (MR) may promote resilience against negative consequences of stress exposure, including childhood trauma. We examined, in mice, whether brain MR overexpression can alleviate the effects of chronic early life stress (ELS) on contextual memory formation under low and high stress conditions, and neurogenesis and synaptic function of dentate gyrus granular cells. Male mice were exposed to ELS by housing the dam with limited nesting and bedding material from postnatal day (PND) 2 to 9. We investigated the moderating role of MRs by using forebrain-specific transgenic MR overexpression (MR-tg) mice. Low-stress contextual (i.e., object relocation) memory formation was hampered by ELS in wildtype but not MR-tg mice. Anxiety like behavior and high-stress contextual (i.e., fear) memory formation were unaffected by ELS and/or MR expression level. At the cellular level, an interaction effect was observed between ELS and MR overexpression on the number of doublecortin-positive cells, with a significant difference between the wildtype ELS and MR-tg ELS groups. No interaction was found regarding Ki-67 and BrdU staining. A significant interaction between ELS and MR expression was further observed with regard to mEPSCs and mIPSC frequency. The ratio of evoked EPSC/IPSC or NMDA/AMPA responses was unaffected. Overall, these results suggest that ELS affects contextual memory formation under low stress conditions as well as neurogenesis and synaptic transmission in dentate granule cells, an effect that can be alleviated by MR-overexpression.

Maternal Licorice Consumption During Pregnancy and Pubertal, Cognitive, and Psychiatric Outcomes in Children

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.

11β-hydroxysteroid dehydrogenase-1 deficiency alters the gut microbiome response to Western diet

The enzyme 11β-hydroxysteroid dehydrogenase (11β-HSD) interconverts active glucocorticoids and their intrinsically inert 11-keto forms. The type 1 isozyme, 11β-HSD1, predominantly reactivates glucocorticoids in vivo and can also metabolise bile acids. 11β-HSD1-deficient mice show altered inflammatory responses and are protected against the adverse metabolic effects of a high-fat diet. However, the impact of 11β-HSD1 on the composition of the gut microbiome has not previously been investigated. We used high-throughput 16S rDNA amplicon sequencing to characterise the gut microbiome of 11β-HSD1-deficient and C57Bl/6 control mice, fed either a standard chow diet or a cholesterol- and fat-enriched 'Western' diet. 11β-HSD1 deficiency significantly altered the composition of the gut microbiome, and did so in a diet-specific manner. On a Western diet, 11β-HSD1 deficiency increased the relative abundance of the family Bacteroidaceae, and on a chow diet, it altered relative abundance of the family Prevotellaceae Our results demonstrate that (i) genetic effects on host-microbiome interactions can depend upon diet and (ii) that alterations in the composition of the gut microbiome may contribute to the aspects of the metabolic and/or inflammatory phenotype observed with 11β-HSD1 deficiency.

Selection and early clinical evaluation of the brain-penetrant 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitor UE2343 (Xanamem™)

Background and Purpose

Reducing glucocorticoid exposure in the brain via intracellular inhibition of the cortisol‐regenerating enzyme 11β‐hydroxysteroid dehydrogenase type 1 (11β‐HSD1) has emerged as a therapeutic strategy to treat cognitive impairment in early Alzheimer's disease (AD). We sought to discover novel, brain‐penetrant 11β‐HSD1 inhibitors as potential medicines for the treatment of AD.

Experimental Approach

Medicinal chemistry optimization of a series of amido‐thiophene analogues was performed to identify potent and selective 11β‐HSD1 inhibitors with optimized oral pharmacokinetics able to access the brain. Single and multiple ascending dose studies were conducted in healthy human subjects to determine the safety, pharmacokinetic and pharmacodynamic characteristics of the candidate compound.

Results

UE2343 was identified as a potent, orally bioavailable, brain‐penetrant 11β‐HSD1 inhibitor and selected for clinical studies. No major safety issues occurred in human subjects. Plasma adrenocorticotropic hormone was elevated (a marker of systemic enzyme inhibition) at doses of 10 mg and above, but plasma cortisol levels were unchanged. Following multiple doses of UE2343, plasma levels were approximately dose proportional and the terminal t_1/2 ranged from 10 to 14 h. The urinary tetrahydrocortisols/tetrahydrocortisone ratio was reduced at doses of 10 mg and above, indicating maximal 11β‐HSD1 inhibition in the liver. Concentrations of UE2343 in the CSF were 33% of free plasma levels, and the peak concentration in CSF was ninefold greater than the UE2343 IC₅₀.

Conclusions and Implications

UE2343 is safe, well tolerated and reaches the brain at concentrations predicted to inhibit 11β‐HSD1. UE2343 is therefore a suitable candidate to test the hypothesis that 11β‐HSD1 inhibition in brain improves memory in patients with AD.

Forebrain-Specific Transgene Rescue of 11β-HSD1 Associates with Impaired Spatial Memory and Reduced Hippocampal Brain-Derived Neurotrophic Factor mRNA Levels in Aged 11β-HSD1 Deficient Mice

Mice lacking the intracellular glucocorticoid-regenerating enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) are protected from age-related spatial memory deficits. 11β-HSD1 is expressed predominantly in the brain, liver and adipose tissue. Reduced glucocorticoid levels in the brain in the absence of 11β-HSD1 may underlie the improved memory in aged 11β-HSD1 deficient mice. However, the improved glucose tolerance, insulin sensitisation and cardioprotective lipid profile associated with reduced peripheral glucocorticoid regeneration may potentially contribute to the cognitive phenotype of aged 11β-HSD1 deficient mice. In the present study, transgenic mice with forebrain-specific overexpression of 11β-HSD1 (Tg) were intercrossed with global 11β-HSD1 knockout mice (HSD1KO) to examine the influence of forebrain and peripheral 11β-HSD1 activity on spatial memory in aged mice. Transgene-mediated delivery of 11β-HSD1 to the hippocampus and cortex of aged HSD1KO mice reversed the improved spatial memory retention in the Y-maze but not spatial learning in the watermaze. Brain-derived neurotrophic factor (BDNF) mRNA levels in the hippocampus of aged HSD1KO mice were increased compared to aged wild-type mice. Rescue of forebrain 11β-HSD1 reduced BDNF mRNA in aged HSD1KO mice to levels comparable to aged wild-type mice. These findings indicate that 11β-HSD1 regenerated glucocorticoids in the forebrain and decreased levels of BDNF mRNA in the hippocampus play a role in spatial memory deficits in aged wild-type mice, although 11β-HSD1 activity in peripheral tissues may also contribute to spatial learning impairments in aged mice.

Thyrotropin Receptor Antibody Levels at Diagnosis and After Thionamide Course Predict Graves' Disease Relapse

BACKGROUND

Thionamides are associated with a high risk of recurrence following cessation. Thyrotropin receptor-stimulating antibody (TRAb) levels at diagnosis and/or after thionamides may be biomarkers of this risk. This study assesses the natural history of Graves' thyrotoxicosis following thionamide withdrawal and factors that predict recurrence, particularly TRAb levels at diagnosis and cessation.

METHODS

An observational study was conducted of patients with a first presentation of Graves' disease, who were prescribed (and completed) a course of primary thionamide treatment (n = 266) in a university teaching hospital endocrine clinic. Recurrence rates over four years and factors predictive of recurrent thyrotoxicosis were assessed.

RESULTS

The relapse rate was 31% at one year and 70% at four years. Younger age (39 years [range 30-49 years] vs. 47 years [range 37-53 years]; p = 0.011), higher TRAb levels at diagnosis (8.8 IU/L [range 5.3-17.0 IU/L] vs. 5.7 IU/L [range 4.1-9.1 IU/L]; p = 0.003), and higher TRAb levels at cessation of therapy (1.2 IU/L [range 0-2.3 IU/L] vs. <0.9 IU/L [range 0-1.3 IU/L]; p = 0.003) were associated with a higher risk of relapse. By four years, cessation TRAb <0.9 IU/L was associated with a 58% risk of recurrence compared with 82% with TRAb >1.5 IU/L (p = 0.001). TRAb at diagnosis >12 IU/L was associated with an 84% risk of recurrence over four years compared with 57% with TRAbs <5 IU/L (p = 0.002).

CONCLUSION

High TRAb at diagnosis and/or positive TRAb at cessation of therapy suggest a high likelihood of relapse, mostly within the first two years. They stratify patients likely to need definitive therapy (radioiodine or surgery).

11β-Hydroxysteroid Dehydrogenase Type 1 Is Expressed in Neutrophils and Restrains an Inflammatory Response in Male Mice

Endogenous glucocorticoid action within cells is enhanced by prereceptor metabolism by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), which converts intrinsically inert cortisone and 11-dehydrocorticosterone into active cortisol and corticosterone, respectively. 11β-HSD1 is highly expressed in immune cells elicited to the mouse peritoneum during thioglycollate-induced peritonitis and is down-regulated as the inflammation resolves. During inflammation, 11β-HSD1-deficient mice show enhanced recruitment of inflammatory cells and delayed acquisition of macrophage phagocytic capacity. However, the key cells in which 11β-HSD1 exerts these effects remain unknown. Here we have identified neutrophils (CD11b(+),Ly6G(+),7/4(+) cells) as the thioglycollate-recruited cells that most highly express 11β-HSD1 and show dynamic regulation of 11β-HSD1 in these cells during an inflammatory response. Flow cytometry showed high expression of 11β-HSD1 in peritoneal neutrophils early during inflammation, declining at later states. In contrast, expression in blood neutrophils continued to increase during inflammation. Ablation of monocytes/macrophages by treatment of CD11b-diphtheria-toxin receptor transgenic mice with diphtheria toxin prior to thioglycollate injection had no significant effect on 11β-HSD1 activity in peritoneal cells, consistent with neutrophils being the predominant 11β-HSD1 expressing cell type at this time. Similar to genetic deficiency in 11β-HSD1, acute inhibition of 11β-HSD1 activity during thioglycollate-induced peritonitis augmented inflammatory cell recruitment to the peritoneum. These data suggest that neutrophil 11β-HSD1 increases during inflammation to contribute to the restraining effect of glucocorticoids upon neutrophil-mediated inflammation. In human neutrophils, lipopolysaccharide activation increased 11β-HSD1 expression, suggesting the antiinflammatory effects of 11β-HSD1 in neutrophils may be conserved in humans.

Placental 5-methylcytosine and 5-hydroxymethylcytosine patterns associate with size at birth

Altered placental function as a consequence of aberrant imprinted gene expression may be one mechanism mediating the association between low birth weight and increased cardiometabolic disease risk. Imprinted gene expression is regulated by epigenetic mechanisms, particularly DNA methylation (5mC) at differentially methylated regions (DMRs). While 5-hydroxymethylcytosine (5hmC) is also present at DMRs, many techniques do not distinguish between 5mC and 5hmC. Using human placental samples, we show that the expression of the imprinted gene CDKN1C associates with birth weight. Using specific techniques to map 5mC and 5hmC at DMRs controlling the expression of CDKN1C and the imprinted gene IGF2, we show that 5mC enrichment at KvDMR and DMR0, and 5hmC enrichment within the H19 gene body, associate positively with birth weight. Importantly, the presence of 5hmC at imprinted DMRs may complicate the interpretation of DNA methylation studies in placenta; future studies should consider using techniques that distinguish between, and permit quantification of, both modifications.

Conditional Deletion of Hsd11b2 in the Brain Causes Salt Appetite and Hypertension

Supplemental Digital Content is available in the text.

Background—

The hypertensive syndrome of Apparent Mineralocorticoid Excess is caused by loss-of-function mutations in the gene encoding 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2), allowing inappropriate activation of the mineralocorticoid receptor by endogenous glucocorticoid. Hypertension is attributed to sodium retention in the distal nephron, but 11βHSD2 is also expressed in the brain. However, the central contribution to Apparent Mineralocorticoid Excess and other hypertensive states is often overlooked and is unresolved. We therefore used a Cre-Lox strategy to generate 11βHSD2 brain-specific knockout (Hsd11b2.BKO) mice, measuring blood pressure and salt appetite in adults.

Methods and Results—

Basal blood pressure, electrolytes, and circulating corticosteroids were unaffected in Hsd11b2.BKO mice. When offered saline to drink, Hsd11b2.BKO mice consumed 3 times more sodium than controls and became hypertensive. Salt appetite was inhibited by spironolactone. Control mice fed the same daily sodium intake remained normotensive, showing the intrinsic salt resistance of the background strain. Dexamethasone suppressed endogenous glucocorticoid and abolished the salt-induced blood pressure differential between genotypes. Salt sensitivity in Hsd11b2.BKO mice was not caused by impaired renal sodium excretion or volume expansion; pressor responses to phenylephrine were enhanced and baroreflexes impaired in these animals.

Conclusions—

Reduced 11βHSD2 activity in the brain does not intrinsically cause hypertension, but it promotes a hunger for salt and a transition from salt resistance to salt sensitivity. Our data suggest that 11βHSD2-positive neurons integrate salt appetite and the blood pressure response to dietary sodium through a mineralocorticoid receptor–dependent pathway. Therefore, central mineralocorticoid receptor antagonism could increase compliance to low-sodium regimens and help blood pressure management in cardiovascular disease.

Effects of Mineralocorticoid Receptor Overexpression on Anxiety and Memory after Early Life Stress in Female Mice

Early-life stress (ELS) is a risk factor for the development of psychopathology, particularly in women. Human studies have shown that certain haplotypes of NR3C2, encoding the mineralocorticoid receptor (MR), that result in gain of function, may protect against the consequences of stress exposure, including childhood trauma. Here, we tested the hypothesis that forebrain-specific overexpression of MR in female mice would ameliorate the effects of ELS on anxiety and memory in adulthood. We found that ELS increased anxiety, did not alter spatial discrimination and reduced contextual fear memory in adult female mice. Transgenic overexpression of MR did not alter anxiety but affected spatial memory performance and enhanced contextual fear memory formation. The effects of ELS on anxiety and contextual fear were not affected by transgenic overexpression of MR. Thus, MR overexpression in the forebrain does not represent a major resilience factor to early life adversity in female mice.

Dynamic Changes in DNA Methylation Occur during the First Year of Life in Preterm Infants

BACKGROUND

Preterm birth associates with a substantially increased risk of later cardiovascular disease and neurodevelopmental disorders. Understanding underlying mechanisms will facilitate the development of screening and intervention strategies to reduce disease risk. Changes in DNA methylation have been proposed as one mechanism linking the early environment with later disease risk. We tested the hypothesis that preterm birth associates with altered DNA methylation in genes encoding insulin-like growth factor 2 (IGF2) and FK506-binding protein 5 (FKBP5), which appear particularly vulnerable to early life adversity.

METHODS

Fifty preterm infants were seen and assessed at birth, term equivalent age, 3 months and 1-year corrected ages; 40 term infants were seen at birth, 3 months and 1 year. Saliva was collected for DNA extraction at birth, term, and 1 year. Pyrosequencing of bisulfite-converted DNA was performed to measure DNA methylation at specific CpG sites within the IGF2 and FKBP5 loci.

RESULTS

Weight and head circumference was reduced in preterm infants at all time points. Preterm infants had a higher percentage body fat at term-corrected age, but this difference was not persistent. DNA methylation at the differentially methylated region (DMR) of IGF2 (IGF2DMR2) and FKBP5 was lower in preterm infants at birth- and term-corrected age compared to term infants at birth. IGF2DMR2 and FKBP5 methylation was related to birthweight SD score in preterm infants. Among preterm infants, social deprivation was an independent contributor toward reducing DNA methylation at IGF2DMR2 at birth- and term-corrected age and maternal smoking was associated with reduced DNA methylation at FKBP5 at birth. There were no persistent differences in DNA methylation at 1 year of age.

CONCLUSION

Changes in DNA methylation were identified at key regions of IGF2/H19 and FKBP5 in preterm infants in early life. Potential contributing factors include maternal smoking and social deprivation. However, these changes did not persist at 1 year of age and further longitudinal studies are required to determine any associations between altered DNA methylation in the perinatal period of individuals born preterm and their long-term health.

Cardiomyocyte and Vascular Smooth Muscle-Independent 11β-Hydroxysteroid Dehydrogenase 1 Amplifies Infarct Expansion, Hypertrophy, and the Development of Heart Failure After Myocardial Infarction in Male Mice

Global deficiency of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), an enzyme that regenerates glucocorticoids within cells, promotes angiogenesis, and reduces acute infarct expansion after myocardial infarction (MI), suggesting that 11β-HSD1 activity has an adverse influence on wound healing in the heart after MI. The present study investigated whether 11β-HSD1 deficiency could prevent the development of heart failure after MI and examined whether 11β-HSD1 deficiency in cardiomyocytes and vascular smooth muscle cells confers this protection. Male mice with global deficiency in 11β-HSD1, or with Hsd11b1 disruption in cardiac and vascular smooth muscle (via SM22α-Cre recombinase), underwent coronary artery ligation for induction of MI. Acute injury was equivalent in all groups. However, by 8 weeks after induction of MI, relative to C57Bl/6 wild type, globally 11β-HSD1-deficient mice had reduced infarct size (34.7 ± 2.1% left ventricle [LV] vs 44.0 ± 3.3% LV, P = .02), improved function (ejection fraction, 33.5 ± 2.5% vs 24.7 ± 2.5%, P = .03) and reduced ventricular dilation (LV end-diastolic volume, 0.17 ± 0.01 vs 0.21 ± 0.01 mL, P = .01). This was accompanied by a reduction in hypertrophy, pulmonary edema, and in the expression of genes encoding atrial natriuretic peptide and β-myosin heavy chain. None of these outcomes, nor promotion of periinfarct angiogenesis during infarct repair, were recapitulated when 11β-HSD1 deficiency was restricted to cardiac and vascular smooth muscle. 11β-HSD1 expressed in cells other than cardiomyocytes or vascular smooth muscle limits angiogenesis and promotes infarct expansion with adverse ventricular remodeling after MI. Early pharmacological inhibition of 11β-HSD1 may offer a new therapeutic approach to prevent heart failure associated with ischemic heart disease.

Decreased maternal hypothalamic-pituitary-adrenal axis activity in very severely obese pregnancy: Associations with birthweight and gestation at delivery

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.

Decreased Npas4 and Arc mRNA Levels in the Hippocampus of Aged Memory-Impaired Wild-Type But Not Memory Preserved 11β-HSD1 Deficient Mice

Mice deficient in the glucocorticoid-regenerating enzyme 11β-HSD1 resist age-related spatial memory impairment. To investigate the mechanisms and pathways involved, we used microarrays to identify differentially expressed hippocampal genes that associate with cognitive ageing and 11β-HSD1. Aged wild-type mice were separated into memory-impaired and unimpaired relative to young controls according to their performance in the Y-maze. All individual aged 11β-HSD1-deficient mice showed intact spatial memory. The majority of differentially expressed hippocampal genes were increased with ageing (e.g. immune/inflammatory response genes) with no genotype differences. However, the neuronal-specific transcription factor, Npas4, and immediate early gene, Arc, were reduced (relative to young) in the hippocampus of memory-impaired but not unimpaired aged wild-type or aged 11β-HSD1-deficient mice. A quantitative reverse transcriptase-polymerase chain reaction and in situ hybridisation confirmed reduced Npas4 and Arc mRNA expression in memory-impaired aged wild-type mice. These findings suggest that 11β-HSD1 may contribute to the decline in Npas4 and Arc mRNA levels associated with memory impairment during ageing, and that decreased activity of synaptic plasticity pathways involving Npas4 and Arc may, in part, underlie the memory deficits seen in cognitively-impaired aged wild-type mice.

Cognitive and Disease-Modifying Effects of 11β-Hydroxysteroid Dehydrogenase Type 1 Inhibition in Male Tg2576 Mice, a Model of Alzheimer's Disease

Chronic exposure to elevated levels of glucocorticoids has been linked to age-related cognitive decline and may play a role in Alzheimer's disease. In the brain, 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) amplifies intracellular glucocorticoid levels. We show that short-term treatment of aged, cognitively impaired C57BL/6 mice with the potent and selective 11β-HSD1 inhibitor UE2316 improves memory, including after intracerebroventricular drug administration to the central nervous system alone. In the Tg2576 mouse model of Alzheimer's disease, UE2316 treatment of mice aged 14 months for 4 weeks also decreased the number of β-amyloid (Aβ) plaques in the cerebral cortex, associated with a selective increase in local insulin-degrading enzyme (involved in Aβ breakdown and known to be glucocorticoid regulated). Chronic treatment of young Tg2576 mice with UE2316 for up to 13 months prevented cognitive decline but did not prevent Aβ plaque formation. We conclude that reducing glucocorticoid regeneration in the brain improves cognition independently of reduced Aβ plaque pathology and that 11β-HSD1 inhibitors have potential as cognitive enhancers in age-associated memory impairment and Alzheimer's dementia.

Hypothalamic-pituitary-adrenal axis dysregulation and cortisol activity in obesity: A systematic review

BACKGROUND

Although there is substantial evidence of differential hypothalamic-pituitary-adrenal (HPA) axis activity in both generalized and abdominal obesity, consistent trends in obesity-related HPA axis perturbations have yet to be identified.

OBJECTIVES

To systematically review the existing literature on HPA activity in obesity, identify possible explanations for inconsistencies in the literature, and suggest methodological improvements for future study.

DATA SOURCES

Included papers used Pubmed, Google Scholar, and the University of California Library search engines with search terms body mass index (BMI), waist-to-hip ratio (WHR), waist circumference, sagittal diameter, abdominal versus peripheral body fat distribution, body fat percentage, DEXA, abdominal obesity, and cortisol with terms awakening response, slope, total daily output, reactivity, feedback sensitivity, long-term output, and 11β-HSD expression.

STUDY ELIGIBILITY CRITERIA

Empirical research papers were eligible provided that they included at least one type of obesity (general or abdominal), measured at least one relevant cortisol parameter, and a priori tested for a relationship between obesity and cortisol.

RESULTS

A general pattern of findings emerged where greater abdominal fat is associated with greater responsivity of the HPA axis, reflected in morning awakening and acute stress reactivity, but some studies did show underresponsiveness. When examined in adipocytes, there is a clear upregulation of cortisol output (due to greater expression of 11β-HSD1), but in hepatic tissue this cortisol is downregulated. Overall obesity (BMI) appears to also be related to a hyperresponsive HPA axis in many but not all studies, such as when acute reactivity is examined.

LIMITATIONS

The reviewed literature contains numerous inconsistencies and contradictions in research methodologies, sample characteristics, and results, which partially precluded the development of clear and reliable patterns of dysregulation in each investigated cortisol parameter.

CONCLUSIONS AND IMPLICATIONS

The literature to date is inconclusive, which may well arise from differential effects of generalized obesity vs. abdominal obesity or from modulators such as sex, sex hormones, and chronic stress. While the relationship between obesity and adipocyte cortisol seems to be clear, further research is warranted to understand how adipocyte cortisol metabolism influences circulating cortisol levels and to establish consistent patterns of perturbations in adrenal cortisol activity in both generalized and abdominal obesity.

Maternal depressive symptoms during pregnancy, placental expression of genes regulating glucocorticoid and serotonin function and infant regulatory behaviors

BACKGROUND

Glucocorticoids and serotonin may mediate the link between maternal environment, fetal brain development and 'programming' of offspring behaviors. The placenta regulates fetal exposure to maternal hormonal signals in animal studies, but few data address this in humans. We measured prospectively maternal depressive symptoms during pregnancy and mRNAs encoding key gene products determining glucocorticoid and serotonin function in term human placenta and explored associations with infant regulatory behaviors.

METHOD

Bi-weekly self-ratings of the Center for Epidemiologic Studies Depression Scale from 12th to 13th gestational week onwards and term placental mRNAs of 11beta-hydroxysteroid dehydrogenase type 2 (HSD2B11), type 1 (HSD1B11), glucocorticoid (NR3C1), mineralocorticoid receptors (NR3C2) and serotonin transporter (SLC6A4) were obtained from 54 healthy mothers aged 32.2 ± 5.3 years with singleton pregnancies and without pregnancy complications. Infant regulatory behaviors (crying, feeding, spitting, elimination, sleeping and predictability) were mother-rated at 15.6 ± 4.2 days.

RESULTS

Higher placental mRNA levels of HSD2B11 [0.41 standard deviation (s.d.) unit increase per s.d. unit increase; 95% confidence interval (CI) 0.13-0.69, p = 0.005], HSD1B11 (0.30, 0.03-0.57, p = 0.03), NR3C1 (0.44, 0.19-0.68, p = 0.001) and SLC6A4 (0.26, 0.00-0.53, p = 0.05) were associated with more regulatory behavioral challenges of the infant. Higher placental NR3C1 mRNA partly mediated the association between maternal depressive symptoms during pregnancy and infant regulatory behaviors (p < 0.05).

CONCLUSIONS

Higher placental expression of genes regulating feto-placental glucocorticoid and serotonin exposure is characteristic of infants with more regulatory behavioral challenges. Maternal depression acts, at least partly, via altering glucocorticoid action in the placenta to impact on offspring regulatory behaviors.

Fetal brain 11β-hydroxysteroid dehydrogenase type 2 selectively determines programming of adult depressive-like behaviors and cognitive function, but not anxiety behaviors in male mice

Stress or elevated glucocorticoids during sensitive windows of fetal development increase the risk of neuropsychiatric disorders in adult rodents and humans, a phenomenon known as glucocorticoid programming. 11β-Hydroxysteroid dehydrogenase type 2 (11β-HSD2), which catalyses rapid inactivation of glucocorticoids in the placenta, controls access of maternal glucocorticoids to the fetal compartment, placing it in a key position to modulate glucocorticoid programming of behavior. However, the importance of the high expression of 11β-HSD2 within the midgestational fetal brain is unknown. To examine this, a brain-specific knockout of 11β-HSD2 (HSD2BKO) was generated and compared to wild-type littermates. HSD2BKO have markedly diminished fetal brain 11β-HSD2, but intact fetal body and placental 11β-HSD2 and normal fetal and placental growth. Despite normal fetal plasma corticosterone, HSD2BKO exhibit elevated fetal brain corticosterone levels at midgestation. As adults, HSD2BKO show depressive-like behavior and have cognitive impairments. However, unlike complete feto-placental deficiency, HSD2BKO show no anxiety-like behavioral deficits. The clear mechanistic separation of the programmed components of depression and cognition from anxiety implies distinct mechanisms of pathogenesis, affording potential opportunities for stratified interventions.

Sex-Differences in the Metabolic Health of Offspring of Parents with Diabetes: A Record-Linkage Study

Maternal diabetes in pregnancy affects offspring health. The impact of parental diabetes on offspring health is unclear. We investigated the impact of parental diabetes on the metabolic-health of adult-offspring who did not themselves have diabetes. Data from the Generation Scotland: Scottish Family Health Study, a population-based family cohort, were record-linked to subjects’ own diabetes medical records. From F₀-parents, we identified F₁-offspring of: mothers with diabetes (OMD, n = 409), fathers with diabetes (OFD, n = 468), no parent with diabetes (ONoPD, n = 2489). Metabolic syndrome, body, biochemical measurements and blood-pressures were compared between F₁-offspring groups by sex. A higher proportion of female OMD had metabolic syndrome than female OFD or ONoPD (P<0.0001). In female offspring, predictors of metabolic syndrome were: having a mother with diabetes (OR = 1.78, CI 1.03–3.07, [reference ONoPD]), body mass index (BMI, OR = 1.21, CI 1.13–1.30) and age (OR = 1.03, CI 1.01–1.06). In male offspring, predictors of metabolic syndrome were: BMI (OR = 1.18, CI 1.09–1.29) and percent body-fat (OR = 1.12, CI 1.05–1.19). In both sexes, OMD had higher blood-pressures than OFD (P<0.0001). In females, OMD had higher glucose (P<0.0001) and percent body-fat (P<0.0001) compared with OFD or ONoPD. OMD and OFD both had increased waist-measurements (P<0.0001), BMI (P<0.0001) and percent body-fat (P<0.0001) compared with ONoPD. Female OMD and OFD had lower HDL-cholesterol levels (P<0.0001) than female ONoPD. Parental diabetes is associated with higher offspring-BMI and body-fat. In female offspring, maternal diabetes increased the odds of metabolic syndrome, even after adjusting for BMI. Further investigations are required to determine the mechanisms involved.

Overexpression of mineralocorticoid receptors does not affect memory and anxiety-like behavior in female mice

Mineralocorticoid receptors (MRs) have been implicated in behavioral adaptation and learning and memory. Since-at least in humans-MR function seems to be sex-dependent, we examined the behavioral relevance of MR in female mice exhibiting transgenic MR overexpression in the forebrain. Transgenic MR overexpression did not affect contextual fear memory or cued fear learning and memory. Moreover, MR overexpressing and control mice discriminated equally well between fear responses in a combined cue and context fear conditioning paradigm. Also context-memory in an object recognition task was unaffected in MR overexpressing mice. We conclude that MR overexpression in female animals does not affect fear conditioned responses and object recognition memory.

Maternal depressive symptoms throughout pregnancy are associated with increased placental glucocorticoid sensitivity

BACKGROUND

Maternal prenatal depression predicts post-partum depression and increases risk of prematurity and low birth weight. These effects may be mediated by altered placental function. We hypothesized that placental function would be influenced by the gestational week of experiencing depressive symptoms and aimed to examine associations between maternal depressive symptoms during pregnancy and placental expression of genes involved in glucocorticoid and serotonin transfer between mother and fetus.

METHOD

We studied women participating in a prospective pregnancy cohort: the Prediction and Prevention of Preeclampsia (PREDO) Study, Helsinki, Finland. Maternal depressive symptoms were assessed at 2-week intervals throughout pregnancy in 56 healthy women with singleton, term pregnancies. Messenger ribonucleic acid (mRNA) levels of glucocorticoid (GR) and mineralocorticoid (MR) receptors and serotonin transporter (SLC6A4), 11β-hydroxysteroid dehydrogenase type 1 (HSD1) and 2 (HSD2) were quantified in placental biopsies.

RESULTS

In adjusted analyses women who reported higher depressive symptoms across the whole pregnancy had higher mRNA levels of GR [effect size 0.31 s.d. units, 95% confidence interval (CI) 0.01-0.60, p = 0.042] and MR (effect size 0.34 s.d. units, 95% CI 0.01-0.68, p = 0.047). These effects were significant for symptoms experienced in the third trimester of pregnancy for GR; findings for MR were also significant for symptoms experienced in the second trimester. GR and MR mRNA levels increased linearly by having the trimester-specific depressive symptoms scores 0, 1 or 2-3 times above the clinical cut-off for depression (p = 0.003, p = 0.049, respectively, and p = 0.004, p = 0.15 in adjusted analyses).

CONCLUSIONS

Our findings offer potential gestational-age-specific mechanisms linking maternal depressive symptoms during pregnancy via placental biology. Future studies will test whether these also link with adverse offspring outcomes.

Generation and 3-Dimensional Quantitation of Arterial Lesions in Mice Using Optical Projection Tomography

The generation and analysis of vascular lesions in appropriate animal models is a cornerstone of research into cardiovascular disease, generating important information on the pathogenesis of lesion formation and the action of novel therapies. Use of atherosclerosis-prone mice, surgical methods of lesion induction, and dietary modification has dramatically improved understanding of the mechanisms that contribute to disease development and the potential of new treatments. Classically, analysis of lesions is performed ex vivo using 2-dimensional histological techniques. This article describes application of optical projection tomography (OPT) to 3-dimensional quantitation of arterial lesions. As this technique is non-destructive, it can be used as an adjunct to standard histological and immunohistochemical analyses. Neointimal lesions were induced by wire-insertion or ligation of the mouse femoral artery whilst atherosclerotic lesions were generated by administration of an atherogenic diet to apoE-deficient mice. Lesions were examined using OPT imaging of autofluorescent emission followed by complementary histological and immunohistochemical analysis. OPT clearly distinguished lesions from the underlying vascular wall. Lesion size was calculated in 2-dimensional sections using planimetry, enabling calculation of lesion volume and maximal cross-sectional area. Data generated using OPT were consistent with measurements obtained using histology, confirming the accuracy of the technique and its potential as a complement (rather than alternative) to traditional methods of analysis. This work demonstrates the potential of OPT for imaging atherosclerotic and neointimal lesions. It provides a rapid, much needed ex vivo technique for the routine 3-dimensional quantification of vascular remodelling.

Adipocyte pseudohypoxia suppresses lipolysis and facilitates benign adipose tissue expansion

Prolyl hydroxylase enzymes (PHDs) sense cellular oxygen upstream of hypoxia-inducible factor (HIF) signaling, leading to HIF degradation in normoxic conditions. In this study, we demonstrate that adipose PHD2 inhibition plays a key role in the suppression of adipocyte lipolysis. Adipose Phd2 gene ablation in mice enhanced adiposity, with a parallel increase in adipose vascularization associated with reduced circulating nonesterified fatty acid levels and normal glucose homeostasis. Phd2 gene-depleted adipocytes exhibited lower basal lipolysis in normoxia and reduced β-adrenergic-stimulated lipolysis in both normoxia and hypoxia. A selective PHD inhibitor suppressed lipolysis in murine and human adipocytes in vitro and in vivo in mice. PHD2 genetic ablation and pharmacological inhibition attenuated protein levels of the key lipolytic effectors hormone-sensitive lipase and adipose triglyceride lipase (ATGL), suggesting a link between adipocyte oxygen sensing and fatty acid release. PHD2 mRNA levels correlated positively with mRNA levels of AB-hydrolase domain containing-5, an activator of ATGL, and negatively with mRNA levels of lipid droplet proteins, perilipin, and TIP47 in human subcutaneous adipose tissue. Therapeutic pseudohypoxia caused by PHD2 inhibition in adipocytes blunts lipolysis and promotes benign adipose tissue expansion and may have therapeutic applications in obesity or lipodystrophy.

Dynamics of DNA methylation at IGF2 in preterm and term infants during the first year of life: an observational study

BACKGROUND

Preterm infants are at increased risk of cardiometabolic disease in later life. Extrauterine growth restriction, catch-up growth, altered adiposity, and abnormal hypothalamic-pituitary-adrenal axis activity could be predisposing factors. Altered DNA methylation (5-methylcytosine, 5mC) might be one underlying mechanism. We hypothesised that preterm infants have altered 5mC at the linked differentially methylated region 2 (DMR2) of IGF2 and the H19 imprinting control region (H19 ICR) compared with term infants over the first year of life.

METHODS

We recruited 46 preterm (range 25 weeks + 2 days' gestation to 31 + 5, mean 28 + 6) and 40 term infants (38 + 3 to 42 + 2 weeks' gestation, mean 40 + 2). Anthropometric variables including body composition were measured at term age and 3 months corrected age with air displacement plethysmography and at 1-year-corrected age with skin-fold thickness. Salivary cortisol was measured at 3 months corrected age after the physical examination. Percentage methylation (%5mC) was analysed with pyrosequencing on buccal DNA. Statistical analysis used Student's t test and multivariate linear regression.

FINDINGS

Preterm infants demonstrated growth deficit early in postnatal life but had greater percentage body fat at term age (β=5·73, p<0·001), but not at 3 months (β=-0·28, p=0·82). Compared with term infants, preterm infants had a blunted cortisol response to physical examination (mean difference 0·38 μg/dL, p=0·024). At birth, preterm infants had a significant decrease in %5mC at DMR2 compared with term infants at birth (β=-11·48, p<0·001) and compared with preterm infants at term-corrected age (t=3·13, p=0·01). By term-corrected age, preterm infants had decreased %5mC at both DMR2 (β=-2·84, p=0·013) and the H19 ICR (β=-2·31, p=0·048) compared with term infants at birth, although this difference disappeared at 1 year. Social deprivation was independently associated with decreased %5mC at DMR2 at birth (β=-1·73, p=0·006) and term-corrected age (β=-0·86, p=0·016) but not at 1 year (β=-0·89, p=0·07).

INTERPRETATION

Our results show that decreased %5mC accompanies the early growth deficit in preterm infants. The marked reduction in %5mC at IGF2 DMR2 in preterm infants at birth compared with term-age supports existing evidence that imprinting at secondary regions is established after fertilisation, whereas imprinting is established during gametogenesis at primary regions (H19 ICR). Both regions might be susceptible to early life stressors such as preterm birth and social deprivation.

FUNDING

Chief Scientist Office of the Scottish Government.

Diurnal and stress-induced intra-hippocampal corticosterone rise attenuated in 11β-HSD1-deficient mice: a microdialysis study in young and aged mice

11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) locally regenerates active glucocorticoids from their inert forms thereby amplifying intracellular levels within target tissues including the brain. We previously showed greater increases in intra-hippocampal corticosterone (CORT) levels upon Y-maze testing in aged wild-type than in 11β-HSD1(-/-) mice coinciding with impaired and intact spatial memory, respectively. Here we examined whether ageing influences 11β-HSD1 regulation of CORT in the dorsal hippocampus under basal conditions during the diurnal cycle and following stress. Intra-hippocampal CORT levels measured by in vivo microdialysis in freely behaving wild-type mice displayed a diurnal variation with peak levels in the evening that were significantly elevated with ageing. In contrast, the diurnal rise in intra-hippocampal CORT levels was greatly diminished in 11β-HSD1(-/-) mice and there was no rise with ageing; basal intra-hippocampal CORT levels were similar to wild-type controls. Furthermore, a short (3 min) swim stress induced a longer lasting increase in intra-hippocampal CORT levels in wild-type mice than in 11β-HSD1(-/-) mice despite no genotypic differences in elevation of plasma CORT. These data indicate that 11β-HSD1 activity contributes substantially to diurnal and stress-induced increases in hippocampal CORT levels. This contribution is even greater with ageing. Thus, 11β-HSD1 inhibition may be an attractive target for treating cognitive impairments associated with stress or ageing.

Short-term inhibition of 11β-hydroxysteroid dehydrogenase type 1 reversibly improves spatial memory but persistently impairs contextual fear memory in aged mice

High glucocorticoid levels induced by stress enhance the memory of fearful events and may contribute to the development of anxiety and posttraumatic stress disorder. In contrast, elevated glucocorticoids associated with ageing impair spatial memory. We have previously shown that pharmacological inhibition of the intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) improves spatial memory in aged mice. However, it is not known whether inhibition of 11β-HSD1 will have any beneficial effects on contextual fear memories in aged mice. Here, we examined the effects of UE2316, a selective 11β-HSD1 inhibitor which accesses the brain, on both spatial and contextual fear memories in aged mice using a vehicle-controlled crossover study design.

Short-term UE2316 treatment improved spatial memory in aged mice, an effect which was reversed when UE2316 was substituted with vehicle. In contrast, contextual fear memory induced by foot-shock conditioning was significantly reduced by UE2316 in a non-reversible manner. When the order of treatment was reversed following extinction of the original fear memory, and a second foot-shock conditioning was given in a novel context, UE2316 treated aged mice (previously on vehicle) now showed increased fear memory compared to vehicle-treated aged mice (previously on UE2316). Renewal of the original extinguished fear memory triggered by exposure to a new environmental context may explain these effects. Thus 11β-HSD1 inhibition reverses spatial memory impairments with ageing while reducing the strength and persistence of new contextual fear memories. Potentially this could help prevent anxiety-related disorders in vulnerable elderly individuals.

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Aged mice were treated with UE2316 using a vehicle-controlled crossover design.

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Short-term UE2316 treatment improves spatial memory in a reversible manner.

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Contextual fear memory retention was impaired with UE2316.

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Contextual fear memory effects persisted following reversal of treatment.

Elevation of 11β-hydroxysteroid dehydrogenase type 2 activity in Holocaust survivor offspring: evidence for an intergenerational effect of maternal trauma exposure

BACKGROUND

Adult offspring of Holocaust survivors comprise an informative cohort in which to study intergenerational transmission of the effects of trauma exposure. Lower cortisol and enhanced glucocorticoid sensitivity have been previously demonstrated in Holocaust survivors with PTSD, and in offspring of Holocaust survivors in association with maternal PTSD. In other work, reduction in the activity of the enzyme 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD-2), which inactivates cortisol, was identified in Holocaust survivors in comparison to age-matched, unexposed Jewish controls. Therefore, we investigated glucocorticoid metabolism in offspring of Holocaust survivors to evaluate if similar enzymatic decrements would be observed that might help to explain glucocorticoid alterations previously shown for Holocaust offspring.

METHODS

Holocaust offspring (n=85) and comparison subjects (n=27) were evaluated with clinical diagnostic interview and self-rating scales, and asked to collect a 24-h urine sample from which concentrations of cortisol and glucocorticoid metabolites were assayed by GCMS. 11β-HSD-2 activity was determined as the ratio of urinary cortisone to cortisol.

RESULTS

Significantly reduced cortisol excretion was observed in Holocaust offspring compared to controls (p=.046), as had been shown for Holocaust survivors. However, 11β-HSD-2 activity was elevated for offspring compared to controls (p=.008), particularly among those whose mothers had been children, rather than adolescents or adults, during World War II (p=.032). The effect of paternal Holocaust exposure could not be reliably investigated in the current sample.

CONCLUSIONS

The inverse association of offspring 11β-HSD-2 activity with maternal age at Holocaust exposure is consistent with the influence of glucocorticoid programming. Whereas a long standing reduction in 11β-HSD-2 activity among survivors is readily interpreted in the context of Holocaust related deprivation, understanding the directional effect on offspring will require replication and further exploration.

Cholestenoic acids regulate motor neuron survival via liver X receptors

Cholestenoic acids are formed as intermediates in metabolism of cholesterol to bile acids, and the biosynthetic enzymes that generate cholestenoic acids are expressed in the mammalian CNS. Here, we evaluated the cholestenoic acid profile of mammalian cerebrospinal fluid (CSF) and determined that specific cholestenoic acids activate the liver X receptors (LXRs), enhance islet-1 expression in zebrafish, and increase the number of oculomotor neurons in the developing mouse in vitro and in vivo. While 3β,7α-dihydroxycholest-5-en-26-oic acid (3β,7α-diHCA) promoted motor neuron survival in an LXR-dependent manner, 3β-hydroxy-7-oxocholest-5-en-26-oic acid (3βH,7O-CA) promoted maturation of precursors into islet-1+ cells. Unlike 3β,7α-diHCA and 3βH,7O-CA, 3β-hydroxycholest-5-en-26-oic acid (3β-HCA) caused motor neuron cell loss in mice. Mutations in CYP7B1 or CYP27A1, which encode enzymes involved in cholestenoic acid metabolism, result in different neurological diseases, hereditary spastic paresis type 5 (SPG5) and cerebrotendinous xanthomatosis (CTX), respectively. SPG5 is characterized by spastic paresis, and similar symptoms may occur in CTX. Analysis of CSF and plasma from patients with SPG5 revealed an excess of the toxic LXR ligand, 3β-HCA, while patients with CTX and SPG5 exhibited low levels of the survival-promoting LXR ligand 3β,7α-diHCA. Moreover, 3β,7α-diHCA prevented the loss of motor neurons induced by 3β-HCA in the developing mouse midbrain in vivo.Our results indicate that specific cholestenoic acids selectively work on motor neurons, via LXR, to regulate the balance between survival and death.

Associations between maternal level of education and occupational status with placental glucocorticoid regeneration and sensitivity

OBJECTIVES

Low socio-economic status (SES) is associated with increased disease risk in the involved and the next generation. The effects of low maternal SES on the offspring may be initiated prenatally. We hypothesized that fetoplacental glucocorticoid exposure might mediate the links. We examined associations between maternal level of education and occupational status (used as indices of SES) and placental expression of genes involved in glucocorticoid exposure and transfer between the mother and foetus.

DESIGN AND PATIENTS

Placental biopsies were obtained from 67 healthy women (age 32.2 ± 5.3 years) with singleton, term pregnancies without obstetric complications who participated in a prospective Prediction and Prevention of Preeclampsia (PREDO) study.

MEASURES

Level of education was self-reported, and occupational status was extracted from hospital records. Relative glucocorticoid receptor (GR; NR3C1), mineralocorticoid receptor (MR; NR3C2) and 11-beta-hydroxysteroid dehydrogenase type 1 (HSD11B1) and 2 (HSD11B2) mRNA levels were quantified by real-time PCR.

RESULTS

Placental GR and HSD11B1 expression increased with decreasing maternal education (unadjusted P-values for linear trend = 0.04 and 0.02 and adjusted P-values = 0.06 and 0.09, respectively). Mothers with primary/secondary education had 52.9% (95% CI, 6.2-99.6, P = 0.03, adjusted P = 0.05) and 79.6% (95% CI, 6.5-153.6, P = 0.03, adjusted P = 0.09) higher GR and HSD11B1 mRNA levels compared with mothers with tertiary education. There were no other significant associations.

CONCLUSIONS

Lower maternal level of education is associated with increased placental GR and HSD11B1 gene expression. This combination may regenerate active glucocorticoids in placenta and increase placental sensitivity to glucocorticoids, potentially leading to greater placental and foetal glucocorticoid exposure.

Post-weaning diet determines metabolic risk in mice exposed to overnutrition in early life

BACKGROUND

Maternal overnutrition during pregnancy is associated with an increased risk of obesity and cardiometabolic disease in the offspring; a phenomenon attributed to 'developmental programming'. The post-weaning development of obesity may associate with exacerbation of the programmed metabolic phenotype. In mice, we have previously shown that exposure to maternal overnutrition causes increased weight gain in offspring before weaning, but exerts no persistent effects on weight or glucose tolerance in adulthood. In order to determine whether post-weaning exposure to a cafeteria diet might lead to an exacerbation of programmed effects, offspring born and raised by mothers on control (CON) or cafeteria (DIO) diets were transferred onto either CON or DIO diets at weaning.

FINDINGS

Post-weaning DIO caused the development of obesity, with hyperglycaemia and hyperinsulinaemia in males; and obesity with hyperinsulinaemia in females and with increased cholesterol levels in both sexes. Exposure to maternal overnutrition during pregnancy and lactation caused only subtle additional effects on offspring phenotype.

CONCLUSIONS

These results suggest that post-weaning exposure to a high-fat high-sugar diet has a more profound effect on offspring weight gain and glucose tolerance than exposure to maternal overnutrition. These data emphasise the importance of optimising early life nutrition in offspring of both obese and lean mothers.

Intrahippocampal glucocorticoids generated by 11β-HSD1 affect memory in aged mice

11Beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) locally amplifies active glucocorticoids within specific tissues including in brain. In the hippocampus, 11β-HSD1 messenger RNA increases with aging. Here, we report significantly greater increases in intrahippocampal corticosterone (CORT) levels in aged wild-type (WT) mice during the acquisition and retrieval trials in a Y-maze than age-matched 11β-HSD1^−/− mice, corresponding to impaired and intact spatial memory, respectively. Acute stress applied to young WT mice led to increases in intrahippocampal CORT levels similar to the effects of aging and impaired retrieval of spatial memory. 11β-HSD1^−/− mice resisted the stress-induced memory impairment. Pharmacologic inhibition of 11β-HSD1 abolished increases in intrahippocampal CORT levels during the Y-maze trials and prevented spatial memory impairments in aged WT mice. These data provide the first in vivo evidence that dynamic increases in hippocampal 11β-HSD1 regenerated CORT levels during learning and retrieval play a key role in age- and stress-associated impairments of spatial memory.

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We followed intrahippocampal corticosterone (CORT) levels in mice during memory testing in a Y-maze.

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Aged 11beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1^−/−) mice resists age-related spatial memory decline in the Y-maze.

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A lower dynamic rise in intrahippocampal CORT levels associates with better memory.

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Acute stress increases intrahippocampal CORT and impairs memory in young mice.

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11β-HSD1 inhibition reduces intrahippocampal CORT and improves memory in aged mice.