Altered amygdala and hippocampus function in adolescents with hypercortisolemia: a functional magnetic resonance imaging study of Cushing syndrome

Neurochemical Anatomy of Cushing's Syndrome

The neurochemical anatomy underlying Cushing's syndrome is examined for regional brain metabolism as well as neurotransmitter levels and receptor binding of biogenic amines and amino acids. Preliminary studies generally indicate that glucose uptake, blood flow, and activation on fMRI scans decreased in neocortical areas and increased in subcortical areas of patients with Cushing's syndrome or disease. Glucocorticoid-mediated increases in hippocampal metabolism occurred despite in vitro evidence of glucocorticoid-induced decreases in glucose uptake or consumption, indicating that in vivo increases are the result of indirect, compensatory, or preliminary responses. In animal studies, glucocorticoid administration decreased 5HT levels and 5HT1A receptor binding in several brain regions while adrenalectomy increased such binding. Region-specific effects were also obtained in regard to the dopaminergic system, with predominant actions of glucocorticoid-induced potentiation of reuptake blockers and releasing agents. More in-depth neuroanatomical analyses are warranted of these and amino acid-related neurotransmission.

Reversibility of Impaired Large-Scale Functional Brain Networks in Cushing's Disease after Surgery Treatment: A Longitudinal Study

INTRODUCTION

Chronic exposure to excessive endogenous cortisol leads to brain changes in Cushing's disease (CD). However, it remains unclear how CD affects large-scale functional networks (FNs) and whether these effects are reversible after treatment. This study aimed to investigate functional network changes of CD patients and their reversibility in a longitudinal cohort.

METHODS

Active CD patients (N = 37) were treated by transsphenoidal pituitary surgery and reexamined 3 months later. FNs were computed from resting-state fMRI data of the CD patients and matched normal controls (NCs, N = 37). A pattern classifier was built on the FNs to distinguish active CD patients from controls and applied to FNs of the CD patients at the 3-month follow-up. Two subgroups of endocrine-remitted CD patients were identified according to their classification scores, referred to as image-based phenotypically (IBP) recovered and unrecovered CD patients, respectively. The informative FNs identified by the classification model were compared between NCs, active CD patients, and endocrine-remitted patients as well as between IBP recovered and unrecovered CD patients to explore their functional network reversibility.

RESULTS

All 37 CD patients reached endocrine remission after treatment. The classification model identified three informative FNs, including cerebellar network (CerebN), fronto-parietal network (FPN), and default mode network. Among them, CerebN and FPN partially recovered toward normal at 3 months after treatment. Moreover, the informative FNs were correlated with 24-h urinary-free cortisol and emotion scales in CD patients.

CONCLUSION

These findings suggest that CD patients have aberrant FNs that are partially reversible toward normal after treatment.

Functional brain alterations in Cushing's syndrome

Cognitive impairment and affective disorders are common in patients with Cushing's syndrome (CS). In fact, as an effect of prolonged cortisol excess on the brain, patients with CS often have memory problems, concentration difficulties, impaired attention and executive function, that are not always reversible following successful treatment. Neuroimaging is essential for understanding the deleterious effects of hypercortisolism on the brain. In CS, structural alterations have been observed, including reduction of hippocampal volume, amygdala and the prefrontal cortex. The aim of this article is to summarize results from studies that have used functional magnetic resonance imaging (fMRI) to study functional brain alterations in patients with CS. In these studies, alterations in brain areas and networks essential for cognitive function, emotional processing, and executive function have been observed, both in patients with active CS as well as following treatment. Nevertheless, longitudinal studies with a comprehensive evaluation of functional brain alterations and neurocognitive evaluation are still needed to determine whether the apparent deleterious effects of hypercortisolism on the brain are reversible or not.

Structural and functional brain alterations in Cushing's disease: A narrative review

Neurocognitive and psychiatric symptoms are non-negligible in Cushing's disease and are accompanied by structural and functional alterations of the brain. In this review, we have summarized multimodal neuroimaging and neurophysiological studies to highlight the current and historical understandings of the structural and functional brain alterations in Cushing's disease. Specifically, structural studies showed atrophy of the gray matter, loss of white matter integrity, and demyelination in widespread brain regions. Functional imaging studies have identified three major functional brain connectome networks influenced by hypercortisolemia: the limbic network, the default mode network, and the executive control network. After endocrinological remission, atrophy of gray matter regions and the compromised functional network activities were partially reversible, and the widespread white matter integrity alterations cannot recover in years. In conclusion, Cushing's disease patients display structural and functional brain connectomic alterations, which provides insights into the neurocognitive and psychiatric symptoms observed in this disease.

Ultra-high field 7 T MRI localizes regional brain volume recovery following corticotroph adenoma resection and hormonal remission in Cushing's disease: A case series

Background

Cushing's disease (CD) is defined by glucocorticoid excess secondary to the increased section of corticotropin by a pituitary adenoma. Magnetic resonance imaging (MRI) studies performed at 1.5 or 3 Tesla (T) have demonstrated correlations between regional changes in brain structure and the progression of CD. In this report, we examine the changes in brain volume following corticotroph pituitary adenoma resection using ultra-high field 7 T MRI to increase the accuracy of our volumetric analyses.

Methods

Thirteen patients were referred to the endocrinology clinic at our institution from 2017 to 2020 with symptoms of cortisol excess and were diagnosed with ACTH-dependent endogenous Cushing syndrome. Five patients had follow-up 7 T imaging at varying time points after a transsphenoidal resection.

Results

Symmetrized percent change in regional volumes demonstrated a postoperative increase in cortical volume that was relatively larger than that of cerebral white matter or subcortical gray matter (percent changes = 0.0172%, 0.0052%, and 0.0120%, respectively). In the left cerebral hemisphere, the medial orbitofrontal, lateral orbitofrontal, and pars opercularis cortical regions experienced the most robust postoperative percent increases (percent changes = 0.0166%, 0.0122%, and 0.0068%, respectively). In the right cerebral hemisphere, the largest percent increases were observed in the pars triangularis, rostral portion of the middle frontal gyrus, and superior frontal gyrus (percent changes = 0.0156%, 0.0120%, and 0.0158%).

Conclusion

Cerebral volume recovery following pituitary adenoma resection is driven by changes in cortical thickness predominantly in the frontal lobe, while subcortical white and gray matter volumes increase more modestly.

Younger age and early puberty are associated with cognitive function decline in children with Cushing disease

OBJECTIVE

To investigate the effect of hypercortisolism on the developing brain we performed clinical, cognitive, and psychological evaluation of children with Cushing disease (CD) at diagnosis and 1 year after remission.

STUDY DESIGN

Prospective study of 41 children with CD. Children completed diverse sets of cognitive measures before and 1 year after remission. Neuropsychological evaluation included the Wechsler Intelligence Scale, California Verbal Learning Test, Trail Making Test, the combined subset scores of Wide Range Achievement Test and Woodcock-Johnson Psychoeducational Battery Test of Achievement, and the Behavioral Assessment System for Children.

RESULTS

Comprehensive cognitive evaluations at baseline and 1 year following cure revealed significant decline mostly in nonverbal skills. Decrements occurred in most of the various indices that measure all aspects of cognitive function and younger age and early pubertal stage largely contributed to most of this decline. Results indicated that age at baseline was associated with positive regression weights for changes in scores for verbal, performance, and full intelligence quotient (IQ) scores and for subtests arithmetic, picture completion, coding, block design, scores; indicating that older age at baseline was associated with less of a deterioration in cognitive scores from pre- to posttreatment.

CONCLUSION

Our findings suggest that chronic glucocorticoid excess and accompanying secondary hormonal imbalances followed by eucortisolemia have detrimental effects on cognitive function in the developing brain; younger age and pubertal stage are risk factors for increased vulnerability, while older adolescents have cognitive vulnerabilities like that of adult patients affected with CD.

Trends in regional morphological changes in the brain after the resolution of hypercortisolism in Cushing's disease: a complex phenomenon, not mere partial reversibility

The adverse effects of hypercortisolism on the human brain have been highlighted in previous studies of Cushing's disease (CD). However, the relative alterations in regional hypercortisolism in the brain remain unclear. Thus, we investigated regional volumetric alterations in CD patients. We also analyzed the associations between these volumetric changes and clinical characteristics. The study participants comprised of active CD (n = 60), short-term-remitted CD (n = 28), and long-term-remitted CD (n = 32) patients as well as healthy control subjects (n = 66). Gray matter volumes (GMVs) were measured via voxel-based morphometry. The GMVs of substructures were defined using the automated anatomical labeling (AAL) atlas. Trends toward normalization in GMV were found in most brain substructures of CD patients. Different trends, including enlarged, irreversible, and unaffected, were observed in the other subregions, such as the amygdala, thalamus, and caudate. Morphological changes in GMVs after the resolution of hypercortisolism are a complex phenomenon; the characteristics of these changes significantly differ within the brain substructures.

Altered microstructural pattern of white matter in Cushing's disease identified by automated fiber quantification

A growing body of evidence suggests that altered brain structure plays a crucial role in the pathogenesis of neuropsychological abnormalities induced by hypercortisolism in patients with Cushing's disease. While most studies mainly focus on gray matter, white matter structure has been largely overlooked. In the current study, we conducted a cross-sectional diffusion tensor imaging study on 58 patients with Cushing's disease and 54 matched healthy individuals to profile the microstructural pattern using automated fiber quantification and investigate its association with neuroendocrine and neuropsychological deficits. The study revealed that microstructural pattern showed a widespread mean diffusivity, radial diffusivity increase, fractional anisotropy decrease and partial axial diffusivity increase among tracts notably in corpus callosum forceps, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, superior longitudinal fasciculus, uncinate fasciculus and arcuate fasciculus, while within the same tract abnormalities localized to specific positions. Moreover, compromised microstructural pattern of white matter in specific tracts and locations along the trajectory were associated with ACTH and cortisol concentration and cognitive decline in patients with Cushing's disease. Collectively, our study elucidates the form of white matter pathology induced by hypercortisolism and its association with cognitive decline which may provide further targets for early identification and intervention of Cushing's disease.

Glucocorticoids, metabolism and brain activity

The review integrates different experimental approaches including biochemistry, c-Fos expression, microdialysis (glutamate, GABA, noradrenaline and serotonin), electrophysiology and fMRI to better understand the effect of elevated level of glucocorticoids on the brain activity and metabolism. The available data indicate that glucocorticoids alter the dynamics of neuronal activity leading to context-specific changes including both excitation and inhibition and these effects are expected to support the task-related responses. Glucocorticoids also lead to diversification of available sources of energy due to elevated levels of glucose, lactate, pyruvate, mannose and hydroxybutyrate (ketone bodies), which can be used to fuel brain, and facilitate storage and utilization of brain carbohydrate reserves formed by glycogen. However, the mismatch between carbohydrate supply and utilization that is most likely to occur in situations not requiring energy-consuming activities lead to metabolic stress due to elevated brain levels of glucose. Excessive doses of glucocorticoids also impair the production of energy (ATP) and mitochondrial oxidation. Therefore, glucocorticoids have both adaptive and maladaptive effects consistently with the concept of allostatic load and overload.

Reversibility of impaired brain structures after transsphenoidal surgery in Cushing's disease: a longitudinal study based on an artificial intelligence-assisted tool

OBJECTIVE

Cushing's disease (CD) involves brain impairments caused by excessive cortisol. Whether these impairments are reversible in remitted CD after surgery has long been controversial due to a lack of high-quality longitudinal studies. In this study the authors aimed to assess the reversibility of whole-brain changes in remitted CD after transsphenoidal surgery (TSS), and its correlations with clinical and hormonal parameters, in the largest longitudinal study cohort to date for CD patient brain analysis.

METHODS

Fifty patients with pathologically diagnosed CD and 36 matched healthy controls (HCs) were enrolled in a tertiary comprehensive hospital and national pituitary disease registry center in China. 3-T MRI studies were analyzed using an artificial intelligence-assisted web-based autosegmentation tool to quantify 3D brain volumes. Clinical parameters as well as levels of serum cortisol, adrenocorticotrophic hormone (ACTH), and 24-hour urinary free cortisol were collected for the correlation analysis. All CD patients underwent TSS and 46 patients achieved remission. All clinical, hormonal, and MRI parameters were reevaluated at the 3-month follow-up after surgery.

RESULTS

Widespread brain volume loss was observed in active CD patients compared with HCs, including total gray matter (p = 0.003, with false discovery rate [FDR] correction) and the frontal, parietal, occipital, and temporal lobes; insula; cingulate lobe; and enlargement of lateral and third ventricles (p < 0.05, corrected with FDR). All affected brain regions improved significantly after TSS (p < 0.05, corrected with FDR). In patients with remitted CD, total gray matter and most brain regions (except the frontal and temporal lobes) showed full recovery of volume, with volumes that did not differ from those of HCs (p > 0.05, corrected with FDR). ACTH and serum cortisol changes were negatively correlated with brain volume changes during recovery (p < 0.05).

CONCLUSIONS

This study demonstrates the rapid reversal of total gray matter loss in remitted CD. The combination of full recovery areas and partial recovery areas after TSS is consistent with the incomplete recovery of memory and cognitive function observed in CD patients in clinical practice. Correlation analyses suggest that ACTH and serum cortisol levels are reliable serum biomarkers of brain recovery for clinical use after surgery.

Neuropsychological Functioning in Patients with Cushing's Disease and Cushing's Syndrome

PURPOSE

To present a systematic review of the presence and severity of neuropsychological impairment in the six main neuropsychological domains (attention, executive function, language, visuospatial processing, intelligence, and memory) in patients with Cushing's disease (CD) and/or Cushing's Syndrome (CS) at various stages of the illness. The work aims to identify neuropsychological leverage points for focused diagnosis and rehabilitation in CS/CD patients.

METHODS

A pubmed literature search was performed and augmented by searching the reference lists of review articles identified by this search strategy. After excluding irrelevant hits, we systematically extracted data from 27 studies for each main neuropsychological domain, differentiating between active disease, short- and long-term remission.

RESULTS

The literature gives evidence for neuropsychological impairment in all domains in Cushing patients with active disease. The most consistent impairments concerned memory and visuo-spatial processing, whereas the data are discordant for all other domains. Significant improvement of neuropsychological function - although not returning to normal in all domains - is shown in short-term and long-term remission of the disease. However, the published literature is thin, suffering from repetitive subsample analyses publishing, methodological concerns as lack of control for confounders such as depression.

CONCLUSIONS

Memory is the most extensively investigated domain in CS/CD patients and impairment is most prominent in active disease. Patients should be counseled that neuropsychological function will improve with normalization of hypercortisolism and over time. More studies with more stringent methodological criteria, larger patient samples and controlling for confounders are required to enhance our understanding of neuropsychological function in patients with CS/CD.

Psychiatric and neurocognitive consequences of endogenous hypercortisolism

Psychiatric and neurocognitive symptoms due to hypercortisolism were already described by Harvey Cushing in his original paper on patients with Cushing's syndrome (CS). Nowadays, it is well known that psychiatric and cognitive complaints are two of the most common, and most distressing, symptoms in patients with CS. Psychiatric symptoms are indeed a major clinical manifestation of CS. The most commonly observed psychiatric conditions are depression and anxiety, whilst mania and psychosis are less common. Several domains of cognitive function are impaired at diagnosis, including episodic and working memory, executive function and attention. Following treatment, one-fourth of the patients still experience depressed mood, and the cognitive impairments are only partially restored. Consequently, quality of life in patients with CS is severely and persistently affected. Neuroimaging studies have also illustrated the deleterious effects of hypercortisolism on the brain by demonstrating reduced grey matter volumes and cortical thickness, altered resting-state functional responses and during cognitive tasks, as well as widespread reduced white matter integrity, especially in structures important for cognitive function and emotional processing, both before and after successful abrogation of hypercortisolism. In this paper, we summarize the current knowledge on the psychiatric and neurocognitive consequences of hypercortisolism in patients with CS, both before, and after successful treatment. In addition, we review the structural and functional brain abnormalities associated with hypercortisolism and discuss the influence of these factors on quality of life.

The aging-liked alterations in Cushing's disease: A neurite orientation dispersion and density imaging (NODDI) study

PURPOSE

Glucocorticoid (GC) is probably related to biological aging, but the exact mechanism remains unknown. Cushing's disease (CD) could represent a unique human model for examining the effects of prolonged exposure to hypercortisolism and its relationship with aging. Thus, we studied the alterations of neurites in CD patients with Neurite orientation dispersion and density imaging (NODDI).

METHODS

CD patients (n = 15) and healthy control subjects (n = 15) were included in this study. Orientation dispersion index (Odi), neurite density index (Ndi), partial fraction of free water (fiso), partial fraction of extracellular water (fec) were examined in a cross-sectional analysis.

RESULTS

Significant altered NODDI parameters were found in CD patients. Some of these alterations were correlated with current age. Additionally, increased dendritic density was found in cerebellar of CD patients.

CONCLUSION

Hypercortisolism relative reductions of the dendritic density were correlated with current age in several regions of CD patients. Our study enhances the understanding of the link between the aging and GC.

Computerized Analysis of Brain MRI Parameter Dynamics in Young Patients With Cushing Syndrome-A Case-Control Study

BACKGROUND

Young patients with Cushing Syndrome (CS) may develop cognitive and behavioral alterations during disease course.

METHODS

To investigate the effects of CS on the brain, we analyzed consecutive MRI scans of patients with (n = 29) versus without CS (n = 8). Multiple brain compartments were processed for total and gray/white matter (GM/WM) volumes and intensities, and cortical volume, thickness, and surface area. Dynamics (last/baseline scans ratio per parameter) were analyzed versus cortisol levels and CS status (persistent, resolved, and non-CS).

RESULTS

Twenty-four-hour urinary free cortisol (24hUFC) measurements had inverse correlation with the intensity of subcortical GM structures and of the corpus callosum, and with the cerebral WM intensity. 24hUFC dynamics had negative correlation with volume dynamics of multiple cerebral and cerebellar structures. Patients with persistent CS had less of an increase in cortical thickness and WM intensity, and less of a decrease in WM volume compared with patients with resolution of CS. Patients with resolution of their CS had less of an increase in subcortical GM and cerebral WM volumes, but a greater increase in cortical thickness of frontal lobe versus controls.

CONCLUSION

Changes in WM/GM consistency, intensity, and homogeneity in patients with CS may correlate with CS clinical consequences better than volume dynamics alone.

Dynamic changes of views on the brain changes of Cushing's syndrome using different computer-assisted tool

Cushing's syndrome (CS) provides a unique model for assessing the neurotoxic effect of chronic hypercortisolism on human brains. With the ongoing development of different computer-assisted tools, four research stages emerged, each with its own pearls and pitfalls. This review summarizes current knowledge and describes the dynamic changes of views on the brain changes of CS, especially in the current era of the rapid development of artificial intelligence and big data. The adverse effects of GC on brain are proven to be on structural, functional and cellular levels at the same time.

Improvement in cognitive impairment following the successful treatment of endogenous Cushing's syndrome-a case report and literature review

BACKGROUND

Endogenous Cushing's syndrome, a rare endocrine disorder, characterised by chronic cortisol hypersecretion, results in neuropsychiatric disturbances and in cognitive deficits, which are only partially reversible after the biochemical remission of the disease.

CASE PRESENTATION

We report a case of a woman with a profound cognitive deficit and a gradual functional decline caused by Cushing's disease of at least 10 years duration. The neurosurgical resection of her 2 mm adrenocorticotropic hormone (ACTH) secreting pituitary microadenoma resulted in a successful resolution of the patient's hypercortisolism and a significant recovery of her neurocognitive function. The patient's progress was evaluated using serial clinical observations, functional assessments, Mini-Mental Status exams and through the formal neuropsychological report. Furthermore, the patient's recovery of her neurocognitive function was reflected by a sustained improvement in the patient's specific structural brain abnormalities on radiological imaging.

CONCLUSIONS

This report illustrates the importance of early detection and treatment of Cushing's syndrome in order to prevent neurocognitive impairment and neuropsychiatric disorders which are associated with an endogenous cortisol hypersecretion. The long term adverse effects of severe hypercortisolaemia on brain function and the pathophysiological mechanisms responsible for the structural and functional changes in brain anatomy due to glucocorticoid excess are reviewed.

Quality of Life in Patients With Cushing's Disease

Cushing's disease (and by extension, Cushing's syndrome) is a rare disease due to a chronic cortisol excess, which usually has an important impact on quality of life (QoL). It can lead to numerous comorbidities that can interfere with daily life, as fatigability, myopathy, bone loss and fragility, increased cardiovascular risk, depression, and cognitive alterations. Of note, psychological alterations (including depression and anxiety) occur often, and are an important determinant of impaired quality QoL. QoL scores using different questionnaires are poorer in comparison to healthy controls, other pituitary adenomas and some chronic diseases. Even if some improvements can be observed after successful treatment, recovery does not seem to be complete, and comorbidities persist. This persistent QoL impairment has been found using both generic and disease-specific QoL questionnaires, and is also reported by the patients themselves, when asked directly. Multidisciplinary teams are essential to improve patients' well-being. Clinicians should take into account the whole scope of clinical problems and address the different comorbidites associated with the disease. Screening in the psychological sphere, with further intervention if necessary, can be helpful in the management of these patients. Interventions and programs have shown promising results, although there is a need for further development of new strategies for the benefit of these patients.

A Role for Phosphodiesterase 11A (PDE11A) in the Formation of Social Memories and the Stabilization of Mood

The most recently discovered 3',5'-cyclic nucleotide phosphodiesterase family is the Phosphodiesterase 11 (PDE11) family, which is encoded by a single gene PDE11A. PDE11A is a dual-specific PDE, breaking down both cAMP and cGMP. There are four PDE11A splice variants (PDE11A1-4) with distinct tissue expression profiles and unique N-terminal regulatory regions, suggesting that each isoform could be individually targeted with a small molecule or biologic. PDE11A4 is the PDE11A isoform expressed in brain and is found in the hippocampal formation of humans and rodents. Studies in rodents show that PDE11A4 mRNA expression in brain is, in fact, restricted to the hippocampal formation (CA1, possibly CA2, subiculum, and the adjacently connected amygdalohippocampal area). Within the hippocampal formation of rodents, PDE11A4 protein is expressed in neurons but not astrocytes, with a distribution across nuclear, cytoplasmic, and membrane compartments. This subcellular localization of PDE11A4 is altered in response to social experience in mouse, and in vitro studies show the compartmentalization of PDE11A4 is controlled, at least in part, by homodimerization and N-terminal phosphorylation. PDE11A4 expression dramatically increases in the hippocampus with age in the rodent hippocampus, from early postnatal life to late aging, suggesting PDE11A4 function may evolve across the lifespan. Interestingly, PDE11A4 protein shows a three to tenfold enrichment in the rodent ventral hippocampal formation (VHIPP; a.k.a. anterior in primates) versus dorsal hippocampal formation (DHIPP). Consistent with this enrichment in VHIPP, studies in knockout mice show that PDE11A regulates the formation of social memories and the stabilization of mood and is a critical mechanism by which social experience feeds back to modify the brain and subsequent social behaviors. PDE11A4 likely controls behavior by regulating hippocampal glutamatergic, oxytocin, and cytokine signaling, as well as protein translation. Given its unique tissue distribution and relatively selective effects on behavior, PDE11A may represent a novel therapeutic target for neuropsychiatric, neurodevelopmental, or age-related disorders. Therapeutically targeting PDE11A4 may be a way to selectively restore aberrant cyclic nucleotide signaling in the hippocampal formation while leaving the rest of the brain and periphery untouched, thus, relieving deficits while avoiding unwanted side effects.

Voxel-based comparison of brain glucose metabolism between patients with Cushing's disease and healthy subjects

Cognitive impairment and psychiatric symptoms are common in patients with Cushing's disease (CD) owing to elevated levels of glucocorticoids. Molecular neuroimaging methods may help to detect changes in the brain of patients with CD. The aim of this study was to investigate the characteristics of brain metabolism and its association with serum cortisol level in CD. We compared brain metabolism, as measured using [¹⁸F]-fluorodeoxyglucose positron emission tomography (FDG PET), between 92 patients with CD and 118 normal subjects on a voxel-wise basis. Pearson correlation was performed to evaluate the association between cerebral FDG uptake and serum cortisol level in patients with CD. We demonstrated that certain brain regions in patients with CD showed significantly increased FDG uptake, including the basal ganglia, anteromedial temporal lobe, thalamus, precentral cortex, and cerebellum. The clusters that demonstrated significantly decreased uptake were mainly located in the medial and lateral frontal cortex, superior and inferior parietal lobule, medial occipital cortex, and insular cortex. The metabolic rate of the majority of these regions was found to be significantly correlated with the serum cortisol level. Our findings may help to explain the underlying mechanisms of cognitive impairment and psychiatric symptoms in patients exposed to excessive glucocorticoids and evaluate the efficacy of treatments during follow-up.

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Hypercortisolism leads to metabolic changes in specific brain regions of CD patients.

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These brain regions involve in the regulation of cortisol and the symptoms of CD.

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The metabolism of 6 specific brain regions is correlated with cortisol level.

Volumetric magnetic resonance imaging analysis in patients with short-term remission of Cushing's disease

OBJECTIVE

The data on patients with short-term remission of Cushing's disease (CD) might provide information that is not available from previous long-term remission studies. We aimed to investigate structural changes in the brain in these patients and to examine whether these changes were associated with clinical characteristics.

DESIGN

A cross-sectional study was performed.

METHODS

Thirty-four patients with CD (14 with CD in short-term remission and 20 with active CD) and 34 controls matched for age, sex and education underwent clinical evaluation and magnetic resonance imaging brain scans. Biometric measurements, disease duration and remission duration data were collected. Grey matter volumes in the whole brain were examined using voxel-based morphometry (VBM).

RESULTS

No differences were observed in the grey matter volumes of the medial frontal gyrus (MFG) and cerebellum between the patients with remitted CD and healthy controls, whereas patients with active CD had smaller grey matter volumes in these two regions compared with controls and patients with remitted CD. Furthermore, significant correlations were found between remission time and grey matter values in these regions in short-term remission patients with CD. Additionally, greater grey matter volumes in the bilateral caudate of short-term remission patients with CD were observed.

CONCLUSIONS

Trends for structural restoration were found in CD patients with short-term remission. This finding was associated with the number of days elapsed since curative surgery and the current age of the patients. This study enhances our understanding of potential reversibility after the resolution of hypercortisolism in CD patients.

Decreased prefrontal functional brain response during memory testing in women with Cushing's syndrome in remission

Neurocognitive dysfunction is an important feature of Cushing's syndrome (CS). Our hypothesis was that patients with CS in remission have decreased functional brain responses in the prefrontal cortex and hippocampus during memory testing. In this cross-sectional study we included 19 women previously treated for CS and 19 controls matched for age, gender, and education. The median remission time was 7 (IQR 6-10) years. Brain activity was studied with functional magnetic resonance imaging during episodic- and working-memory tasks. The primary regions of interest were the prefrontal cortex and the hippocampus. A voxel-wise comparison of functional brain responses in patients and controls was performed. During episodic-memory encoding, patients displayed lower functional brain responses in the left and right prefrontal gyrus (p<0.001) and in the right inferior occipital gyrus (p<0.001) compared with controls. There was a trend towards lower functional brain responses in the left posterior hippocampus in patients (p=0.05). During episodic-memory retrieval, the patients displayed lower functional brain responses in several brain areas with the most predominant difference in the right prefrontal cortex (p<0.001). During the working memory task, patients had lower response in the prefrontal cortices bilaterally (p<0.005). Patients, but not controls, had lower functional brain response during a more complex working memory task compared with a simpler one. In conclusion, women with CS in long-term remission have reduced functional brain responses during episodic and working memory testing. This observation extends previous findings showing long-term adverse effects of severe hypercortisolaemia on brain function.

Depression and Anxiety Scores Are Associated with Amygdala Volume in Cushing's Syndrome: Preliminary Study

Introduction

Cushing's syndrome (CS) has repeatedly been associated with hippocampal volume reductions, while little information is available on the amygdala, another structure rich in glucocorticoid receptors. The aim of the study was to analyze amygdala volume in patients with CS and its relationship with anxiety, depression, and hormone levels.

Material and Methods

39 CS patients (16 active and 23 patients in remission) and 39 healthy controls matched for age, sex, and education level completed anxiety (STAI) and depression tests (BDI-II) and underwent a 3 Tesla brain MRI and endocrine testing. Amygdala volumes were analysed with FreeSurfer software.

Results

Active CS patients had smaller right (but not left) amygdala volumes when compared to controls (P = 0.045). Left amygdala volumes negatively correlated with depression scores (r = −0.692, P = 0.003) and current anxiety state scores (r = −0.617, P = 0.011) in active CS patients and with anxiety trait scores (r = −0.440, P = 0.036) in patients in remission. No correlations were found between current ACTH, urinary free cortisol or blood cortisol levels, and amygdala volumes in either patient group.

Conclusion

Patients with active CS have a smaller right amygdala volume in comparison to controls, while left amygdala volumes are associated with mood state in both patient groups.

Brain glucose metabolism is associated with hormone level in Cushing's disease: A voxel-based study using FDG-PET

Chronic exposure to elevated levels of glucocorticoids can exert a neurotoxic effect in patients, possibly manifesting as molecular imaging alterations in patients. The aim of this study was to investigate the potential association between brain metabolism and elevated hormone level using ¹⁸F-fluorodeoxyglucose positron emission tomography. We retrospectively enrolled 92 consecutive patients with confirmed diagnosis of Cushing's disease. A voxel-based analysis was performed to investigate the association between cerebral ¹⁸F-fluorodeoxyglucose uptake and serum cortisol level. Relatively impaired metabolism of specific brain regions correlated with serum cortisol level was found. Specifically, notable correlations were found in the hippocampus, amygdala, and cerebellum, regions considered to be involved in the regulation and central action of glucocorticoids. Moreover, some hormone-associated regions were found in the frontal and occipital cortex, possibly mediating the cognitive changes seen in Cushing's disease. Our findings link patterns of perturbed brain metabolism relates to individual hormone level, thus presenting a substrate for cognitive disturbances seen in Cushing's disease patients, as well as in other conditions with abnormal cortisol levels.

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Specific brain regions correlated with serum cortisol level was found.

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Some of these brain regions validate previous findings.

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Some other brain regions could be new targets for further studies.

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These findings may help to evaluate the brain functions and efficacy of treatments.

Cognitive Changes in Chronic Kidney Disease and After Transplantation

Cognitive impairment is very common in chronic kidney disease (CKD) and is strongly associated with increased mortality. This review article will discuss the pathophysiology of cognitive impairment in CKD, as well as the effect of dialysis and transplantation on cognitive function. In CKD, uremic toxins, hyperparathyroidism and Klotho deficiency lead to chronic inflammation, endothelial dysfunction and vascular calcifications. This results in an increased burden of cerebrovascular disease in CKD patients, who consistently have more white matter hyperintensities, microbleeds, microinfarctions and cerebral atrophy on magnetic resonance imaging scans. Hemodialysis, although beneficial in terms of uremic toxin clearance, also contributes to cognitive decline by causing rapid fluid and osmotic shifts. Decreasing the dialysate temperature and increasing total dialysis time limits these shifts and helps maintain cognitive function in hemodialysis patients. For many patients, kidney transplantation is the preferred treatment modality, because it reverses the underlying mechanisms causing cognitive impairment in CKD. These positive effects have to be balanced against the possible neurotoxicity of infections and immunosuppressive medications, especially glucocorticosteroids and calcineurin inhibitors. A limited number of studies have addressed the overall effect of transplantation on cognitive function. These have mostly found an improvement after transplantation, but have a limited applicability to daily practice because they have only included relatively young patients.

Cases of Psychiatric Morbidity in Pediatric Patients After Remission of Cushing Syndrome

Endogenous Cushing syndrome (CS) may have different effects in children than what has been described in adults. Previous studies of children and adolescents with CS have identified cognitive decline despite reversal of brain atrophy after remission of CS. Although the observations of parents of children and adolescents with CS support personality changes, significant psychopathology has not been described in the literature. We report 9 children who underwent successful surgery (transsphenoidal surgery [TSS] or resection of bronchial carcinoid) for treatment of CS and subsequently developed significant affective pathology. Affective symptoms included anger-rage outbursts, suicidal ideation, irritability, anxiety, and depression. One child, who committed suicide 60 months after TSS, had recently discontinued antidepressant medication. She had a history of anxiety during active CS and was treated with an anxiolytic. The 7 patients with onset of symptoms within 7 months of TSS were on glucocorticoid replacement, and 1-year follow-up evaluation showed recovery of hypothalamic-pituitary-adrenal axis and biochemical evidence of remission. The 2 patients who presented with onset of symptoms at 48 months or later underwent endocrine evaluation that showed biochemical evidence of remission and normal anterior pituitary hormone levels. This is the first report of affective symptoms and behavioral dysregulation, including suicidal ideation, in a subgroup of children and adolescents after remission of CS. Health care providers caring for children with CS who have been cured should continue to screen for mental illness, monitor for changes in behavior, and refer as appropriate to mental health professionals.

Genetic Moderation of Stress Effects on Corticolimbic Circuitry

Stress exposure is associated with individual differences in corticolimbic structure and function that often mirror patterns observed in psychopathology. Gene x environment interaction research suggests that genetic variation moderates the impact of stress on risk for psychopathology. On the basis of these findings, imaging genetics, which attempts to link variability in DNA sequence and structure to neural phenotypes, has begun to incorporate measures of the environment. This research paradigm, known as imaging gene x environment interaction (iGxE), is beginning to contribute to our understanding of the neural mechanisms through which genetic variation and stress increase psychopathology risk. Although awaiting replication, evidence suggests that genetic variation within the canonical neuroendocrine stress hormone system, the hypothalamic-pituitary-adrenal axis, contributes to variability in stress-related corticolimbic structure and function, which, in turn, confers risk for psychopathology. For iGxE research to reach its full potential it will have to address many challenges, of which we discuss: (i) small effects, (ii) measuring the environment and neural phenotypes, (iii) the absence of detailed mechanisms, and (iv) incorporating development. By actively addressing these challenges, iGxE research is poised to help identify the neural mechanisms underlying genetic and environmental associations with psychopathology.

Altered neural processing of emotional faces in remitted Cushing's disease

Patients with long-term remission of Cushing's disease (CD) demonstrate residual psychological complaints. At present, it is not known how previous exposure to hypercortisolism affects psychological functioning in the long-term. Earlier magnetic resonance imaging (MRI) studies demonstrated abnormalities of brain structure and resting-state connectivity in patients with long-term remission of CD, but no data are available on functional alterations in the brain during the performance of emotional or cognitive tasks in these patients. We performed a cross-sectional functional MRI study, investigating brain activation during emotion processing in patients with long-term remission of CD. Processing of emotional faces versus a non-emotional control condition was examined in 21 patients and 21 matched healthy controls. Analyses focused on activation and connectivity of two a priori determined regions of interest: the amygdala and the medial prefrontal-orbitofrontal cortex (mPFC-OFC). We also assessed psychological functioning, cognitive failure, and clinical disease severity. Patients showed less mPFC activation during processing of emotional faces compared to controls, whereas no differences were found in amygdala activation. An exploratory psychophysiological interaction analysis demonstrated decreased functional coupling between the ventromedial PFC and posterior cingulate cortex (a region structurally connected to the PFC) in CD-patients. The present study is the first to show alterations in brain function and task-related functional coupling in patients with long-term remission of CD relative to matched healthy controls. These alterations may, together with abnormalities in brain structure, be related to the persisting psychological morbidity in patients with CD after long-term remission.

MECHANISMS IN ENDOCRINOLOGY: Cushing's syndrome causes irreversible effects on the human brain: a systematic review of structural and functional magnetic resonance imaging studies

BACKGROUND

Cushing's syndrome (CS) is characterized by excessive exposure to cortisol, and is associated with both metabolic and behavioral abnormalities. Symptoms improve substantially after biochemical cure, but may persist during long-term remission. The causes for persistent morbidity are probably multi-factorial, including a profound effect of cortisol excess on the brain, a major target area for glucocorticoids.

OBJECTIVE

To review publications evaluating brain characteristics in patients with CS using magnetic resonance imaging (MRI).

METHODS

Systematic review of literature published in PubMed, Embase, Web of Knowledge, and Cochrane databases.

RESULTS

Nineteen studies using MRI in patients with CS were selected, including studies in patients with active disease, patients in long-term remission, and longitudinal studies, covering a total of 339 unique patients. Patients with active disease showed smaller hippocampal volumes, enlarged ventricles, and cerebral atrophy as well as alterations in neurochemical concentrations and functional activity. After abrogation of cortisol excess, the reversibility of structural and neurochemical alterations was incomplete after long-term remission. MRI findings were related to clinical characteristics (i.e., cortisol levels, duration of exposure to hypercortisolism, current age, age at diagnosis, and triglyceride levels) and behavioral outcome (i.e., cognitive and emotional functioning, mood, and quality of life).

CONCLUSION

Patients with active CS demonstrate brain abnormalities, which only partly recover after biochemical cure, because these still occur even after long-term remission. CS might be considered as a human model of nature that provides a keyhole perspective of the neurotoxic effects of exogenous glucocorticoids on the brain.

Neuropsychiatric disorders in Cushing's syndrome

Endogenous Cushing's syndrome (CS), a rare endocrine disorder characterized by cortisol hypersecretion, is associated with psychiatric and neurocognitive disorders. Major depression, mania, anxiety, and neurocognitive impairment are the most important clinical abnormalities. Moreover, patients most often complain of impairment in quality of life, interference with family life, social, and work performance. Surprisingly, after hypercortisolism resolution, despite the improvement of the overall prevalence of psychiatric and neurocognitive disorders, the brain volume loss at least partially persists and it should be noted that some patients may still display depression, anxiety, panic disorders, and neurocognitive impairment. This brief review aimed at describing the prevalence of psychiatric and neurocognitive disorders and their characterization both during the active and remission phases of CS. The last section of this review is dedicated to quality of life, impaired during active CS and only partially resolved after resolution of hypercortisolism.

Effects of cocaine on the hypothalamic-pituitary-adrenal axis

INTRODUCTION

Cocaine hydrochloride is a psychoactive substance extracted from the leaves of plants called Erythroxylum coca. Cocaine is the second most commonly used drug in the world after cannabis; 20 % of cocaine users will become long-term cocaine-dependent patients. Different routes of administration may be recognized: smokable modality, intranasal and intravenous. Cocaine is a potent stimulant of the sympathetic nervous system and causes structural changes on the brain, heart, lung, liver and kidney. It has long been known that use of cocaine may produce alterations to the endocrine system. Research on behavioral and neuroendocrine effects of cocaine dates back several years ago and has increasingly focused on alterations of the hypothalamic-pituitary-adrenal (HPA) axis, which appears to be the chief target of cocaine effects.

STUDIES

Animal (mainly rats and monkeys) and human studies have clearly shown a close relation between cocaine consumption and overdrive of the HPA axis. Such activation is likely involved, though via a still undefined mechanism, in the behavioral and cardiovascular changes of drug abusers as well as in the reinforcement/relapse phenomena. Further studies of the pathophysiology of cocaine addicts will help to devise new therapeutic strategies for these patients.

Persistent Comorbidities in Cushing’s Syndrome after Endocrine Cure

It was assumed that resolution of hypercortisolism in Cushing syndrome (CS) was followed by normalization of morbidity; however, in the last decade evidence is accumulating that patients with cured CS still have increased morbidity and mortality after the biochemical control of hypercortisolism. Patients with CS have an increased cardiovascular and metabolic risk and persistent accumulation of central fat, with an unfavorable adipokine profile, not only during the active phase of the disease but also long after biochemical remission. Clinical management should be particularly careful in identifying global cardiovascular risk, as a primary goal during the followup of these patients, aimed at improving global vascular morbidity. Moreover bone mass is reduced not only due to the endogenous hypercortisolism but also due to duration and dose of exogenous glucocorticoid (GC) replacement therapy after surgery. Thus, therapy in operated patients with inhibition of the hypothalamic-pituitary-adrenal axis should be reduced to the lowest dose and duration possible. Specific treatments should be considered in patients with decreased bone mass, aimed at reducing the increased fracture incidence. Finally, cognitive and health related quality of life impairments, described in active disease, are still abnormal after endocrine cure. Thus, residual morbidity persists in cured CS, suggesting irreversibility of GC-induced phenomena, typical of chronic hypercortisolism.

Disruption of fetal hormonal programming (prenatal stress) implicates shared risk for sex differences in depression and cardiovascular disease

Comorbidity of major depressive disorder (MDD) and cardiovascular disease (CVD) represents the fourth leading cause of morbidity and mortality worldwide, and women have a two times greater risk than men. Thus understanding the pathophysiology has widespread implications for attenuation and prevention of disease burden. We suggest that sex-dependent MDD-CVD comorbidity may result from alterations in fetal programming consequent to the prenatal maternal environments that produce excess glucocorticoids, which then drive sex-dependent developmental alterations of the fetal hypothalamic-pituitary-adrenal (HPA) axis circuitry impacting mood, stress regulation, autonomic nervous system (ANS), and the vasculature in adulthood. Evidence is consistent with the hypothesis that disruptions of pathways associated with gamma aminobutyric acid (GABA) in neuronal and vascular development and growth factors have critical roles in key developmental periods and adult responses to injury in heart and brain. Understanding the potential fetal origins of these sex differences will contribute to development of novel sex-dependent therapeutics.

Neuropsychiatric findings in Cushing syndrome and exogenous glucocorticoid administration

This article reviews the neuropsychiatric presentations elicited by spontaneous hypercortisolism and exogenous supraphysiologic glucocorticoids. Patients with Cushing disease and syndrome develop a depressive syndrome: irritable and depressed mood, decreased libido, disrupted sleep and cognitive decrements. Exogenous short-term glucocorticoid administration may elicit a hypomanic syndrome with mood, sleep and cognitive disruptions. Treatment options are discussed. Brain imaging and neuropsychological studies indicate elevated cortisol and other glucocorticoids are especially deleterious to hippocampus and frontal lobe. The research findings also shed light on neuropsychiatric abnormalities in conditions that have substantial subgroups exhibiting elevated and dysregulated cortisol: aging, major depressive disorder and Alzheimer's disease.

Quality of life and other outcomes in children treated for Cushing syndrome

CONTEXT

Cushing syndrome (CS) in children is associated with residual impairment in measures of health-related quality of life, even after successful resolution of hypercortisolemia, highlighting the need for early identification of morbidities and improvements in long-term management of these patients.

EVIDENCE ACQUISITION AND SYNTHESIS

A PubMed, Scopus, and Web of Science search of articles from 1900 onward identified available studies related to quality of life and complications of pediatric CS as well as important historical articles. This review summarizes studies through November 2012 and highlights recent developments.

CONCLUSIONS

A review of the literature identifies significant morbidities associated with CS of pediatric onset, which must not be treated in isolation. CS affects children and adolescents in many ways that are different than adults. Post-treatment challenges for the child or adolescent treated for CS include: optimize growth and pubertal development, normalize body composition, and promote psychological health and cognitive maturation. All these factors impact health-related quality of life, which is an important outcome measure to assess the burden of disease as well as the effect of treatment. Future research efforts are needed to improve management of the physical, psychological, and emotional aspects of this disease in order to diminish the residual impairments experienced by the pediatric CS patient population.

Threat bias in mice with inactivating mutations of Prkar1a

Anxiety disorders are associated with abnormalities in the neural processing of threat-related stimuli. However, the neurobiological mechanisms underlying threat bias in anxiety are not well understood. We recently reported that a Prkar1a heterozygote (Prkar1a(+/-)) mouse with haploinsufficiency for the main regulatory subunit (R1α) of protein kinase A (PKA) exhibits an anxiety-like phenotype associated with increased cAMP signaling in the amygdala. Prkar1a(+/-) mice provide a novel model to test the direct effect of altered PKA expression and subsequent anxiety-like behavioral phenotype on the response to threat. We hypothesized that Prkar1a(+/-)mice would exhibit a bias in threat detection since increased amygdala activity during emotional stimuli is associated with a maladaptive response. We measured behavior and PKA activity in brain areas after exposure to predator or control odor exposure in male Prkar1a(+/-) and wild-type (WT) littermates. Indeed, there were significant differences in the behavioral response to threat detection; WT mice showed the expected response of decrease in exploratory behavior during predator vs. control odor exposure, while Prkar1a(+/-) mice did not alter their behavior between conditions. Basal and total PKA activity was independently associated with genotype, with an interaction between genotype and threat condition. Prkar1a(+/-) mice had higher PKA activity in amygdala and ventromedial hypothalamus in response to predator odor. In contrast, WT mice had higher PKA activity in amygdala and orbitofrontal cortex after exposure to control odor. Dysregulated PKA activity in the amygdala-prefrontal cortex circuitry in Prkar1a(+/-) mice is associated with behavioral phenotype of anxiety and a bias for threat. This is likely related to a failure to inhibit the amydgala response, which is an effect of the genotype. These results suggest that the alteration in PKA signaling in Prkar1a(+/-) mice is not ubiquitous in the brain; tissue-specific effects of the cAMP/PKA pathway are related to threat detection and fear sensitization.

Idle behaviors of the hippocampus reflect endogenous cortisol levels in youth

OBJECTIVE

Compelling evidence indicates that disruption in functional connectivity (FC) in brain networks underlies many psychiatric and developmental disorders. Current theory posits that biological (i.e., cortisol) and environmental (i.e., stress) experiences in early life are strong determinants in the development of functional brain systems and formative in the genesis of such disorders. The objective of this study was to examine the extent to which individual differences in cortisol concentrations during FC magnetic resonance imaging (MRI) would map onto variability in hippocampal to default mode network (DMN) connectivity in typically developing youth.

METHOD

Salivary cortisol and FC MRI data were collected concurrently in 33 scan-naive 7- to 15-year-old participants. Twenty-nine of these participants previously completed the Trier Social Stress Test. Hippocampal to DMN FC and endogenous cortisol variability during MRI were examined. A possible association between MRI cortisol and cortisol response to the Trier Social Stress Test during the preceding visit or a participant's ratings of anxiety during MRI was tested.

RESULTS

There were significant positive relations between MRI cortisol levels and measurements in the following 3 areas: hippocampal to DMN FC during the resting state, cortisol levels during the Trier Social Stress Test, and fear/anxiety ratings during MRI. Fear/anxiety ratings during MRI also related to self-reported anxiety on standardized measurements.

CONCLUSIONS

This study shows for the first time that FC of the hippocampus is altered with changing cortisol responsivity in youth. Altered FC during the resting state may represent altered alertness or monitoring resulting from variation in glucocorticoid function in youth, which carries implications for the effect of stress on response monitoring and decision making.

FKBP5 and emotional neglect interact to predict individual differences in amygdala reactivity

Individual variation in physiological responsiveness to stress mediates risk for mental illness and is influenced by both experiential and genetic factors. Common polymorphisms in the human gene for FK506 binding protein 5 (FKBP5), which is involved in transcriptional regulation of the hypothalamic-pituitary-adrenal (HPA) axis, have been shown to interact with childhood abuse and trauma to predict stress-related psychopathology. In the current study, we examined if such gene-environment interaction effects may be related to variability in the threat-related reactivity of the amygdala, which plays a critical role in mediating physiological and behavioral adaptations to stress including modulation of the HPA axis. To this end, 139 healthy Caucasian youth completed a blood oxygen level-dependent functional magnetic resonance imaging probe of amygdala reactivity and self-report assessments of emotional neglect (EN) and other forms of maltreatment. These individuals were genotyped for 6 FKBP5 polymorphisms (rs7748266, rs1360780, rs9296158, rs3800373, rs9470080 and rs9394309) previously associated with psychopathology and/or HPA axis function. Interactions between each SNP and EN emerged such that risk alleles predicted relatively increased dorsal amygdala reactivity in the context of higher EN, even after correcting for multiple testing. Two different haplotype analyses confirmed this relationship as haplotypes with risk alleles also exhibited increased amygdala reactivity in the context of higher EN. Our results suggest that increased threat-related amygdala reactivity may represent a mechanism linking psychopathology to interactions between common genetic variants affecting HPA axis function and childhood trauma.

Mineralocorticoid receptor Iso/Val (rs5522) genotype moderates the association between previous childhood emotional neglect and amygdala reactivity

OBJECTIVE

The amygdala is especially reactive to threatening stimuli, and the degree of reactivity predicts individual differences in the expression of depression and anxiety. Emerging research suggests that emotional neglect during childhood as well as hypercortisolemia may lead to heightened threat-related amygdala reactivity. This raises the possibility that genetic variation affecting hypothalamic-pituitary-adrenal (HPA) axis function contributes to individual differences in amygdala reactivity, both independently and as a function of childhood emotional neglect.

METHOD

This study assessed whether the mineralocorticoid receptor iso/val polymorphism (rs5522), a functional genetic variant affecting HPA axis function, influenced threat-related amygdala reactivity in 279 individuals in late childhood and early adolescence. The study also explored the extent to which any effects of the genotype on amygdala reactivity were contingent upon previous childhood emotional neglect.

RESULTS

Prior childhood emotional neglect and the val allele were associated with greater amygdala reactivity. Moreover, a significant genotype-by-emotional neglect interaction was observed whereby greater amygdala reactivity in val allele carriers was independent of previous childhood emotional neglect, while greater reactivity in iso homozygotes was revealed only in the context of a history of elevated emotional neglect. At relatively low levels of previous emotional neglect, val carriers had heightened amygdala reactivity relative to iso homozygotes.

CONCLUSIONS

These results suggest that relatively greater amygdala reactivity may represent a biological mechanism through which childhood adversity and functional genetic variation in HPA axis responsiveness to stress may mediate risk for psychopathology.

Advances in the epidemiology, pathogenesis, and management of Cushing's syndrome complications

Cushing's syndrome (CS) is a clinical condition resulting from chronic exposure to glucocorticoid excess. As a consequence, hypercortisolism contributes significantly to the early development of systemic disorders by direct and/or indirect effects. Complications such as obesity, hypertension, diabetes, dyslipidemia, and hypercoagulability cause premature atherosclerosis and increase cardiovascular mortality. Impairment of the skeletal system is a relevant cause of morbidity and disability in these patients especially due to the high prevalence of vertebral fractures. In addition, muscle weakness, emotional lability, depression, and impairment of quality of life are very common. Clinical management of these patients is complex and should be particularly careful in identifying global cardiovascular risks and aim at controlling all complications. Although the primary goal in the prevention and treatment of complications is the correction of hypercortisolism, treatment does not completely eliminate these comorbidities. Given that cardiovascular risk and fracture risk can persist after cure, early detection of each morbidity could prevent the development of irreversible damage. In this review we present the various complications of CS and their pathogenetic mechanisms. We also suggest the clinical management of these patients based on our extensive clinical experience and on the available literature.

Visuospatial associative memory and hippocampal functioning in congenital hypothyroidism

Congenital hypothyroidism is a pediatric endocrine disorder caused by insufficient endogenous thyroid hormone production. Children with congenital hypothyroidism have difficulties with episodic memory and abnormalities in hippocampal structure, suggesting deficient hippocampal functioning. To assess hippocampal activation in adolescents with congenital hypothyroidism (N = 14; age range, 11.5-14.7 years) compared with controls (N = 15; age range, 11.2-15.5 years), a functional magnetic resonance imaging visuospatial memory task was used. In this task, participants had to decide if object pairings were novel or were previously studied or if object pairs were in the same location as they were at study or had switched locations. Despite no group differences in task performance, adolescents with congenital hypothyroidism showed both increased magnitude of hippocampal activation relative to controls and bilateral hippocampal activation when only the left was observed in controls. Furthermore, the increased activation in the congenital hypothyroidism group was correlated with the severity of the hypothyroidism experienced early in life. These results suggest that perinatal deprivation of thyroid hormone has longstanding effects on hippocampal function and may account for memory problems experienced by adolescents with congenital hypothyroidism.

Hypothyroidism and mood disorders: integrating novel insights from brain imaging techniques

Abstract

Thyroid hormones play a critical role in brain development but also in the adult human brain by modulating metabolic activity. Hypothyroid states are associated with both functional and structural brain alterations also seen in patients with major depression. Recent animal experimental and preclinical data indicate subtle changes in myelination, microvascular density, local neurogenesis, and functional networks. The translational validity of such studies is obviously limited. Clinical evidence for neurobiological correlates of different stages and severities of hypothyroidism and effects of pharmacological intervention is lacking but may be achieved using advanced imaging techniques, e.g. functional and quantitative MRI techniques applied to patients with hypothyroidism before and after hormone replacement therapy.

Emotional memory in early steroid abnormalities: an FMRI study of adolescents with congenital adrenal hyperplasia

Hormonal imbalances during development may have long-lasting effects. Using functional magnetic resonance imaging (fMRI), we compared 14 youths with Congenital Adrenal Hyperplasia (CAH), a genetic disorder of hormonal dysfunction, with 22 healthy controls on memory encoding of emotional faces. Patients remembered fewer faces than controls, particularly fearful faces. FMRI data to successfully encoded fearful faces revealed that males with CAH showed significant activations in amygdala, hippocampus, and anterior cingulate relative to unaffected males, while females with CAH demonstrated deactivations relative to unaffected females in these regions. Findings indicate that steroid abnormalities during development can have important effects on neural correlates of emotional memory.

Psychosomatic aspects of Cushing's syndrome

There has been growing interest in the psychosocial aspects of Cushing's syndrome, such as the role of life stress as a pathogenetic factor, the association with affective disorders, and the presence of residual symptoms after treatment. Interestingly, a temporal relationship between stressful life events and disease onset is relevant only to pituitary-dependent Cushing's disease, and not to the pituitary-independent forms. A number of psychiatric and psychological disturbances may be associated with the active hypercortisolemic state, regardless of its etiology. Within the high frequency of mood disorders (about 60%), major depression is the most common complication. Other psychopathological aspects include mania, anxiety disorders, psychological symptoms (demoralization, irritable mood, somatization) and cognitive impairment. Cognitive symptoms are associated with brain abnormalities (mainly loss of brain volume). Quality of life may be seriously compromised during both active and post-treatment phases. Long-standing hypercortisolism may imply a degree of irreversibility of the pathological process. Recovery, thus, may be delayed and be influenced by highly individualized affective responses. Outcomes of Cushing's syndrome treatment are not fully satisfactory. Within its great complexity, a conceptual shift from a merely biomedical care to a psychosomatic consideration of the person and his/her quality of life appears to be necessary to improve effectiveness. It is time to translate the research evidence that has accumulated into clinical practice initiatives. To patients who show persistence or even worsening of psychological distress upon adequate endocrine treatment psychiatric/psychological interventions should be readily available. Applying interdisciplinary expertise and addressing the needs for rehabilitation would markedly improve final outcome.

A preliminary study of medial temporal lobe function in youths with a history of caregiver deprivation and emotional neglect

Previous research findings have linked caregiver deprivation and emotional neglect with sensitivity to threatening cues. The present preliminary study investigated whether dysfunctions of the medial temporal lobe could underlie these associations. Using fMRI, we measured medial temporal lobe responses to emotional faces (angry, fearful, happy, neutral) among 30 youths. Eleven of the youths had a history of caregiver deprivation and emotional neglect. Attention states (i.e., attention to anger, fear, or physical attributes, or passive viewing) were systematically manipulated. Relative to comparison youths, youths with a history of caregiver deprivation and emotional neglect showed significantly greater left amygdala and left anterior hippocampus activation during the processing of threatening information. To our knowledge, these findings are the first to demonstrate altered medial temporal lobe function during the processing of threat cues in youths with a history of caregiver deprivation and emotional neglect.

A review of adversity, the amygdala and the hippocampus: a consideration of developmental timing

A review of the human developmental neuroimaging literature that investigates outcomes following exposure to psychosocial adversity is presented with a focus on two subcortical structures – the hippocampus and the amygdala. Throughout this review, we discuss how a consideration of developmental timing of adverse experiences and age at measurement might provide insight into the seemingly discrepant findings across studies. We use findings from animal studies to suggest some mechanisms through which timing of experiences may result in differences across time and studies. The literature suggests that early life may be a time of heightened susceptibility to environmental stressors, but that expression of these effects will vary by age at measurement.

Steroid abnormalities and the developing brain: declarative memory for emotionally arousing and neutral material in children with congenital adrenal hyperplasia

Steroid hormones modulate memory in animals and human adults. Little is known on the developmental effects of these hormones on the neural networks underlying memory. Using Congenital adrenal hyperplasia (CAH) as a naturalistic model of early steroid abnormalities, this study examines the consequences of CAH on memory and its neural correlates for emotionally arousing and neutral material in children. Seventeen patients with CAH and 17 age- and sex-matched healthy children (ages 12-14 years) completed the study. Subjects were presented positive, negative and neutral pictures. Memory recall occurred about 30min after viewing the pictures. Children with CAH showed memory deficits for negative pictures compared to healthy children (p<0.01). There were no group differences on memory performance for either positive or neutral pictures (p>0.1). In patients, 24h urinary-free cortisol levels (reflecting glucocorticoid replacement therapy) and testosterone levels were not associated with memory performance. These findings suggest that early steroid imbalances affect memory for negative material in children with CAH. Such memory impairments may result from abnormal brain organization and function following hormonal dysfunction during critical periods of development.