Steroids and apparent cerebral atrophy on computed tomography scans

Drug-Induced Cognitive Impairment

Drug-induced cognitive impairment (DICI) is a well-established, yet under-recognised, complication of many types of pharmacological treatment. While there is a large body of scientific literature on DICI, most papers are about drug-induced dementia in the elderly and one specific drug class. However, DICI also comprises subclinical symptoms, domain-specific forms of cognitive impairment as well as mild cognitive impairment (MCI), and delirium. Even mild forms of DICI, if not recognised as such, can have deleterious and life-long consequences. In addition, DICI also occurs in younger adults and in children, and has been reported with many different drug classes. The aim of this review is to raise awareness of DICI by providing an overview on the type(s) and symptoms of observed DICI and the suspected underlying mechanism(s) for various drug classes: antiseizure medications, antidepressants, antiparkinsonian drugs, antipsychotics, lithium, benzodiazepines/Z-drugs, opioids, first-generation antihistamines, drugs for urinary incontinence, proton pump inhibitors, glucocorticoids, NSAIDs, statins, antihypertensives, and chemotherapeutic agents.

Kidney-brain axis in the pathogenesis of cognitive impairment

The kidney-brain axis is a bidirectional communication network connecting the kidneys and the brain, potentially affected by inflammation, uremic toxin, vascular injury, neuronal degeneration, and so on, leading to a range of diseases. Numerous studies emphasize the disruptions of the kidney-brain axis may contribute to the high morbidity of neurological disorders, such as cognitive impairment (CI) in the natural course of chronic kidney disease (CKD). Although the pathophysiology of the kidney-brain axis has not been fully elucidated, epidemiological data indicate that patients at all stages of CKD have a higher risk of developing CI compared with the general population. In contrast to other reviews, we mentioned some commonly used medicines in CKD that may play a pivotal role in the pathogenesis of CI. Revealing the pathophysiology interactions between kidney damage and brain function can reduce the potential risk of future CI. This review will deeply explore the characteristics, indicators, and potential pathophysiological mechanisms of CKD-related CI. It will provide a theoretical basis for identifying CI that progresses during CKD and ultimately prevents and treats CKD-related CI.

Treating the Side Effects of Exogenous Glucocorticoids; Can We Separate the Good From the Bad?

It is estimated that 2% to 3% of the population are currently prescribed systemic or topical glucocorticoid treatment. The potent anti-inflammatory action of glucocorticoids to deliver therapeutic benefit is not in doubt. However, the side effects associated with their use, including central weight gain, hypertension, insulin resistance, type 2 diabetes (T2D), and osteoporosis, often collectively termed iatrogenic Cushing's syndrome, are associated with a significant health and economic burden. The precise cellular mechanisms underpinning the differential action of glucocorticoids to drive the desirable and undesirable effects are still not completely understood. Faced with the unmet clinical need to limit glucocorticoid-induced adverse effects alongside ensuring the preservation of anti-inflammatory actions, several strategies have been pursued. The coprescription of existing licensed drugs to treat incident adverse effects can be effective, but data examining the prevention of adverse effects are limited. Novel selective glucocorticoid receptor agonists and selective glucocorticoid receptor modulators have been designed that aim to specifically and selectively activate anti-inflammatory responses based upon their interaction with the glucocorticoid receptor. Several of these compounds are currently in clinical trials to evaluate their efficacy. More recently, strategies exploiting tissue-specific glucocorticoid metabolism through the isoforms of 11β-hydroxysteroid dehydrogenase has shown early potential, although data from clinical trials are limited. The aim of any treatment is to maximize benefit while minimizing risk, and within this review we define the adverse effect profile associated with glucocorticoid use and evaluate current and developing strategies that aim to limit side effects but preserve desirable therapeutic efficacy.

Glucocorticoids and cognitive function: a walkthrough in endogenous and exogenous alterations

PURPOSE

The hypothalamic-pituitary-adrenal (HPA) axis exerts many actions on the central nervous system (CNS) aside from stress regulation. Glucocorticoids (GCs) play an important role in affecting several cognitive functions through the effects on both glucocorticoid (GR) and mineralocorticoid receptors (MR). In this review, we aim to unravel the spectrum of cognitive dysfunction secondary to derangement of circulating levels of endogenous and exogenous glucocorticoids.

METHODS

All relevant human prospective and retrospective studies published up to 2022 in PubMed reporting information on HPA disorders, GCs, and cognition were included.

RESULTS

Cognitive impairment is commonly found in GC-related disorders. The main brain areas affected are the hippocampus and pre-frontal cortex, with memory being the most affected domain. Disease duration, circadian rhythm disruption, circulating GCs levels, and unbalanced MR/GR activation are all risk factors for cognitive decline in these patients, albeit with conflicting data among different conditions. Lack of normalization of cognitive dysfunction after treatment is potentially attributable to GC-dependent structural brain alterations, which can persist even after long-term remission.

CONCLUSION

The recognition of cognitive deficits in patients with GC-related disorders is challenging, often delayed, or mistaken. Prompt recognition and treatment of underlying disease may be important to avoid a long-lasting impact on GC-sensitive areas of the brain. However, the resolution of hormonal imbalance is not always followed by complete recovery, suggesting irreversible adverse effects on the CNS, for which there are no specific treatments. Further studies are needed to find the mechanisms involved, which may eventually be targeted for treatment strategies.

Long-term effects of glucocorticoid excess on the brain

The metabolic and cardiovascular clinical manifestations in patients with Cushing's syndrome (CS) are generally well known. However, recent studies have broadened the perspective of the effects of hypercortisolism, showing that both endogenous and exogenous glucocorticoid excess alter brain functioning on several time scales. Consequently, cognitive deficits and neuropsychological symptoms are highly prevalent during both active CS and CS in remission, as well as during glucocorticoid treatment. In this review, we discuss the effects of endogenous hypercortisolism and exogenously induced glucocorticoid excess on the brain, as well as the prevalence of cognitive and neuropsychological deficits and their course after biochemical remission. Furthermore, we propose possible mechanisms that may underly neuronal changes, based on experimental models and in vitro studies. Finally, we offer recommendations for future studies.

Anti-NMDA receptor encephalitis and brain atrophy in children and adults: A quantitative study

PURPOSE

To determine whether brain atrophy was present in patients with anti-N-methyl-d-aspartate receptor encephalitis (anti-NMDARE) using qualitative and quantitative analyses of brain magnetic resonance imaging (MRI) and to explore clinical differences in patients with anti-NMDARE with or without brain atrophy.

METHODS

A retrospective observational study encompassing the serologic, cerebrospinal fluid, and brain MRI data of 23 patients with anti-NMDARE was conducted. Median patient age was 14 years (interquartile range [IQR], 12 years). The cohort included 15 children (<18 years old) and 8 adults (≥18 years old). There were 6 male and 17 female patients. Imaging analysis involved 2 expert readers' observations of MRIs and automated volumetric quantification using NeuroQuant (CorTechs Labs, Inc.) software.

RESULTS

Of 23 pediatric and adult patients, 11 patients had 14 brain MRIs that were quantitatively analyzed. Quantitative NeuroQuant volumetric analysis showed atrophy in 9 of 14 MRIs for 7 of 11 patients compared to age-controlled normative data. In these 9 MRIs, atrophy was present in the temporal lobes (n = 9), cerebral cortex (n = 3), and cerebellum (n = 3). Qualitative analysis of 59 MRIs (23 patients) revealed volume loss in 6 patients: 5 with global cerebral and temporal lobe volume loss and 1 with temporal lobe volume loss. No patient showed cerebellar volume loss on qualitative analysis. Mean length of stay in the intensive care unit was not significantly different for patients with or without quantitative volume loss (3.5 [5.2] vs 27.4 [23.4] days; p = 0.08).

CONCLUSIONS

In this cohort of patients with anti-NMDARE, quantitative volumetric analysis showed brain atrophy, particularly affecting the temporal lobes, in 64% (7/11) of the patients. Qualitative analysis showed brain atrophy in 26% (6/23). These findings highlight the increased sensitivity of quantitative methods for volume loss detection. Larger studies are needed.

Dexamethasone-Induced Perturbations in Tissue Metabolomics Revealed by Chemical Isotope Labeling LC-MS analysis

Dexamethasone (Dex) is a synthetic glucocorticoid (GC) drug commonly used clinically for the treatment of several inflammatory and immune-mediated diseases. Despite its broad range of indications, the long-term use of Dex is known to be associated with specific abnormalities in several tissues and organs. In this study, the metabolomic effects on five different organs induced by the chronic administration of Dex in the Sprague–Dawley rat model were investigated using the chemical isotope labeling liquid chromatography-mass spectrometry (CIL LC-MS) platform, which targets the amine/phenol submetabolomes. Compared to controls, a prolonged intake of Dex resulted in significant perturbations in the levels of 492, 442, 300, 186, and 105 metabolites in the brain, skeletal muscle, liver, kidney, and heart tissues, respectively. The positively identified metabolites were mapped to diverse molecular pathways in different organs. In the brain, perturbations in protein biosynthesis, amino acid metabolism, and monoamine neurotransmitter synthesis were identified, while in the heart, pyrimidine metabolism and branched amino acid biosynthesis were the most significantly impaired pathways. In the kidney, several amino acid pathways were dysregulated, which reflected impairments in several biological functions, including gluconeogenesis and ureagenesis. Beta-alanine metabolism and uridine homeostasis were profoundly affected in liver tissues, whereas alterations of glutathione, arginine, glutamine, and nitrogen metabolism pointed to the modulation of muscle metabolism and disturbances in energy production and muscle mass in skeletal muscle. The differential expression of multiple dipeptides was most significant in the liver (down-regulated), brain (up-regulation), and kidney tissues, but not in the heart or skeletal muscle tissues. The identification of clinically relevant pathways provides holistic insights into the tissue molecular responses induced by Dex and understanding of the underlying mechanisms associated with their side effects. Our data suggest a potential role for glutathione supplementation and dipeptide modulators as novel therapeutic interventions to mitigate the side effects induced by Dex therapy.

Proteomic Analysis of Morphologically Changed Tissues after Prolonged Dexamethasone Treatment

Prolonged dexamethasone (Dex) administration leads to serious adverse and decrease brain and heart size, muscular atrophy, hemorrhagic liver, and presence of kidney cysts. Herein, we used an untargeted proteomic approach using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for simultaneous identification of changes in proteomes of the major organs in Sprague–Dawley (SD rats post Dex treatment. The comparative and quantitative proteomic analysis of the brain, heart, muscle, liver, and kidney tissues revealed differential expression of proteins (n = 190, 193, 39, 230, and 53, respectively) between Dex-treated and control rats. Functional network analysis using ingenuity pathway analysis (IPA revealed significant differences in regulation of metabolic pathways within the morphologically changed organs that related to: (i) brain—cell morphology, nervous system development, and function and neurological disease; (ii) heart—cellular development, cellular function and maintenance, connective tissue development and function; (iii) skeletal muscle—nucleic acid metabolism, and small molecule biochemical pathways; (iv) liver—lipid metabolism, small molecular biochemistry, and nucleic acid metabolism; and (v) kidney—drug metabolism, organism injury and abnormalities, and renal damage. Our study provides a comprehensive description of the organ-specific proteomic profilesand differentially altered biochemical pathways, after prolonged Dex treatement to understand the molecular basis for development of side effects.

Influence of full-length dystrophin on brain volumes in mouse models of Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) affects besides muscle also the brain, resulting in memory and behavioral problems. The consequences of dystrophinopathy on gross macroscopic alterations are unclear. To elucidate the effect of full-length dystrophin expression on brain morphology, we used high-resolution post-mortem MRI in mouse models that either express 0% (mdx), 100% (BL10) or a low amount of full-length dystrophin (mdx-XistΔhs). While absence or low amounts of full-length dystrophin did not significantly affect whole brain volume and skull morphology, we found differences in volume of individual brain structures. The results are in line with observations in humans, where whole brain volume was found to be reduced only in patients lacking both full-length dystrophin and the shorter isoform Dp140.

Promising Links between Meditation and Reduced (Brain) Aging: An Attempt to Bridge Some Gaps between the Alleged Fountain of Youth and the Youth of the Field

Over the last decade, an increasing number of studies has reported a positive impact of meditation on cerebral aging. However, the underlying mechanisms for these seemingly brain-protecting effects are not well-understood. This may be due to the fact, at least partly, that systematic empirical meditation research has emerged only recently as a field of scientific scrutiny. Thus, on the one hand, critical questions remain largely unanswered; and on the other hand, outcomes of existing research require better integration to build a more comprehensive and holistic picture. In this article, we first review theories and mechanisms pertaining to normal (brain) aging, specifically focusing on telomeres, inflammation, stress regulation, and macroscopic brain anatomy. Then, we summarize existing research integrating the developing evidence suggesting that meditation exerts positive effects on (brain) aging, while carefully discussing possible mechanisms through which these effects may be mediated.

Association of Progressive Cerebellar Atrophy With Long-term Outcome in Patients With Anti-N-Methyl-d-Aspartate Receptor Encephalitis

IMPORTANCE

Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis is an immune-mediated disorder that occurs with IgG antibodies against the GluN1 subunit of NMDAR. Some patients develop reversible diffuse cerebral atrophy (DCA), but the long-term clinical significance of progressive brain and cerebellar atrophy is unknown.

OBJECTIVE

To report the long-term clinical implications of DCA and cerebellar atrophy in anti-NMDAR encephalitis.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective observational study and long-term imaging investigation was conducted in the Department of Neurology at Kitasato University. Fifteen patients with anti-NMDAR encephalitis admitted to Kitasato University Hospital between January 1, 1999, and December 31, 2014, were included; data analysis was conducted between July 15, 2015, and January 18, 2016.

EXPOSURES

Neurologic examination, immunotherapy, and magnetic resonance imaging (MRI) studies were performed.

MAIN OUTCOMES AND MEASURES

Long-term MRI changes in association with disease severity, serious complications (eg, pulmonary embolism, septic shock, and rhabdomyolysis), treatment, and outcome.

RESULTS

The clinical outcome of 15 patients (median age, 21 years, [range, 14-46 years]; 10 [67%] female) was evaluated after a median follow-up of 68 months (range, 10-179 months). Thirteen patients (87%) received first-line immunotherapy (intravenous high-dose methylprednisolone, intravenous immunoglobulin, and plasma exchange alone or combined), and 4 individuals (27%) also received cyclophosphamide; 2 patients (13%) did not receive immunotherapy. In 5 patients (33%), ovarian teratoma was found and removed. Serious complications developed in 4 patients (27%). Follow-up MRI revealed DCA in 5 patients (33%) that, in 2 individuals (13%), was associated with progressive cerebellar atrophy. Long-term outcome was good in 13 patients (87%) and poor in the other 2 individuals (13%). Although cerebellar atrophy was associated with poor long-term outcome (2 of 2 vs 0 of 13 patients; P = .01), other features, such as DCA without cerebellar atrophy, serious complications, ventilatory support, or prolonged hospitalization, were not associated with a poor outcome. Five patients with DCA had longer hospitalizations (11.1 vs 2.4 months; P = .002), required ventilatory support more frequently (5 of 5 vs 4 of 10 patients; P = .04), and developed more serious complications (4 of 5 vs 0 of 10 patients; P = .004) compared with those without DCA. Although DCA was reversible, cerebellar atrophy was irreversible.

CONCLUSIONS AND RELEVANCE

In anti-NMDAR encephalitis, DCA can be reversible and does not imply a poor clinical outcome. In contrast, cerebellar atrophy was irreversible and associated with a poor outcome. This observation deserves further study to confirm progressive cerebellar atrophy as a prognostic marker of poor outcome.

Brain pathways to recovery from alcohol dependence

This article highlights the research presentations at the satellite symposium on "Brain Pathways to Recovery from Alcohol Dependence" held at the 2013 Society for Neuroscience Annual Meeting. The purpose of this symposium was to provide an up to date overview of research efforts focusing on understanding brain mechanisms that contribute to recovery from alcohol dependence. A panel of scientists from the alcohol and addiction research field presented their insights and perspectives on brain mechanisms that may underlie both recovery and lack of recovery from alcohol dependence. The four sessions of the symposium encompassed multilevel studies exploring mechanisms underlying relapse and craving associated with sustained alcohol abstinence, cognitive function deficit and recovery, and translational studies on preventing relapse and promoting recovery. Gaps in our knowledge and research opportunities were also discussed.

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.

Reduced age-related degeneration of the hippocampal subiculum in long-term meditators

Normal aging is known to result in a reduction of gray matter within the hippocampal complex, particularly in the subiculum. The present study was designed to address the question whether the practice of meditation can amend this age-related subicular atrophy. For this purpose, we established the correlations between subicular volume and chronological age within 50 long-term meditators and 50 control subjects. High-resolution magnetic resonance imaging (MRI) scans were automatically processed combining cytoarchitectonically defined probabilistic maps with advanced tissue segmentation and registration methods. Overall, we observed steeper negative regression slopes in controls. The analysis further revealed a significant group-by-age interaction for the left subiculum with a significant negative correlation between age and subicular volume in controls, but no significant correlation in meditators. Altogether, these findings seem to suggest a reduced age-related atrophy of the left subiculum in meditators compared to healthy controls. Possible explanations might be a relative increase of subicular tissue over time through long-term training as meditation is a process that incorporates regular and ongoing mental efforts. Alternatively, because meditation is an established form of reducing stress, our observation might reflect an overall preservation of subicular tissue through a reduced neuronal vulnerability to negative effects of stress.

Impaired slow wave sleep downscaling in patients with infantile spasms

BACKGROUND

West syndrome is a severe epileptic encephalopathy of infancy, characterized by infantile spasms, global retardation, and a severely abnormal electroencephalogram (EEG) pattern known as hypsarrhythmia, which is most prominent during slow waves sleep. The restorative function of slow wave sleep has been linked to downscaling, a neuronal process ensuring a balance of global synaptic strength, which is important for normal cortical functioning and development. A key electrophysiological marker for this downscaling is the reduction of the slope of slow waves across the night.

METHODS

We retrospectively compared the slope of slow waves between 14 untreated patients with infantile spasms and healthy age and gender matched controls. Patients were examined in one all-night sleep EEG before treatment, and in two follow-up nap recordings, under and after treatment with corticosteroids.

RESULTS

In patients with infantile spasms the overnight reduction in the slope of slow waves was significantly diminished compared to controls (p = 0.009). Moreover, untreated patients revealed overall steeper slopes. During corticosteroid treatment the slope was reduced compared to controls (p = 0.001). After successful treatment the slope was similar between patients and controls.

CONCLUSION

Our results provide evidence for reduced downscaling in patients with infantile spasms. Moreover, the marked reduction of the slope during corticosteroid treatment may reflect a loss of synaptic connections due to the effect of glucocorticoids. This altered sleep dependent regulation of synaptic strength in infantile spasms may contribute the underlying pathomechanism of the developmental regression. Furthermore the normalization of synaptic strength due to corticosteroids might provide a potential mechanistic explanation for this treatment strategy.

Adrenal disorders and the paediatric brain: pathophysiological considerations and clinical implications

Various neurological and psychiatric manifestations have been recorded in children with adrenal disorders. Based on literature review and on personal case-studies and case-series we focused on the pathophysiological and clinical implications of glucocorticoid-related, mineralcorticoid-related, and catecholamine-related paediatric nervous system involvement. Childhood Cushing syndrome can be associated with long-lasting cognitive deficits and abnormal behaviour, even after resolution of the hypercortisolism. Exposure to excessive replacement of exogenous glucocorticoids in the paediatric age group (e.g., during treatments for adrenal insufficiency) has been reported with neurological and magnetic resonance imaging (MRI) abnormalities (e.g., delayed myelination and brain atrophy) due to potential corticosteroid-related myelin damage in the developing brain and the possible impairment of limbic system ontogenesis. Idiopathic intracranial hypertension (IIH), a disorder of unclear pathophysiology characterised by increased cerebrospinal fluid (CSF) pressure, has been described in children with hypercortisolism, adrenal insufficiency, and hyperaldosteronism, reflecting the potential underlying involvement of the adrenal-brain axis in the regulation of CSF pressure homeostasis. Arterial hypertension caused by paediatric adenomas or tumours of the adrenal cortex or medulla has been associated with various hypertension-related neurological manifestations. The development and maturation of the central nervous system (CNS) through childhood is tightly regulated by intrinsic, paracrine, endocrine, and external modulators, and perturbations in any of these factors, including those related to adrenal hormone imbalance, could result in consequences that affect the structure and function of the paediatric brain. Animal experiments and clinical studies demonstrated that the developing (i.e., paediatric) CNS seems to be particularly vulnerable to alterations induced by adrenal disorders and/or supraphysiological doses of corticosteroids. Physicians should be aware of potential neurological manifestations in children with adrenal dysfunction to achieve better prevention and timely diagnosis and treatment of these disorders. Further studies are needed to explore the potential neurological, cognitive, and psychiatric long-term consequences of high doses of prolonged corticosteroid administration in childhood.

Reversible brain atrophy and cognitive impairment in an adolescent Japanese patient with primary adrenal Cushing's syndrome

Endogenous Cushing's syndrome is an endocrine disease resulting from chronic exposure to excessive glucocorticoids produced in the adrenal cortex. Although the ultimate outcome remains uncertain, functional and morphological brain changes are not uncommon in patients with this syndrome, and generally persist even after resolution of hypercortisolemia. We present an adolescent patient with Cushing's syndrome who exhibited cognitive impairment with brain atrophy. A 19-year-old Japanese male visited a local hospital following 5 days of behavioral abnormalities, such as money wasting or nighttime wandering. He had hypertension and a 1-year history of a rounded face. Magnetic resonance imaging (MRI) revealed apparently diffuse brain atrophy. Because of high random plasma cortisol levels (28.7 μg/dL) at 10 AM, he was referred to our hospital in August 2011. Endocrinological testing showed adrenocorticotropic hormone-independent hypercortisolemia, and abdominal computed tomography demonstrated a 2.7 cm tumor in the left adrenal gland. The patient underwent left adrenalectomy in September 2011, and the diagnosis of cortisol-secreting adenoma was confirmed histologically. His hypertension and Cushingoid features regressed. Behavioral abnormalities were no longer observed, and he was classified as cured of his cognitive disturbance caused by Cushing's syndrome in February 2012. MRI performed 8 months after surgery revealed reversal of brain atrophy, and his subsequent course has been uneventful. In summary, the young age at onset and the short duration of Cushing's syndrome probably contributed to the rapid recovery of both cognitive dysfunction and brain atrophy in our patient. Cushing's syndrome should be considered as a possible etiological factor in patients with cognitive impairment and brain atrophy that is atypical for their age.

A mechanism of rapidly reversible cerebral ventricular enlargement independent of tissue atrophy

Ventricular enlargement, a common in vivo marker of aging, disease, and insult, is presumed to reflect atrophy of surrounding brain regions. Pathological mechanisms underlying ventricular enlargement, however, are likely specific to the condition under investigation. Here, multimodal imaging, incorporating structural magnetic resonance imaging (MRI), MR spectroscopy (MRS), and diffusion weighted imaging (DWI), was used in rats exposed to binge ethanol (EtOH) to provide insight into a mechanism of reversible ventricular enlargement. During intoxication, MRI revealed expansion of ventricles, but volume changes in dorsal or ventral hippocampi, caudate-putamen, or thalamus were not detectible. MRS of whole-brain parenchyma showed decreases in N-acetylasparate (NAA) and tissue water T2, and increases in choline-containing compounds (Cho). DWI showed decreased diffusivity selective to the thalamus. All MR parameters returned to baseline with 7 days of recovery. Rapid recovery of ventricular volume and the absence of detectable tissue volume reductions in brain regions adjacent to ventricles argue against atrophy as a mechanism of ventricular expansion. Decreased tissue water T2 and decreased thalamic diffusivity suggest lower tissue water content and a role for both NAA and Cho, as osmolytes is proposed. Together, these data support a model of fluid redistribution during acute EtOH intoxication and recovery to account for rapid ventricular volume changes.

Changes in brain size during the menstrual cycle

Background

There is increasing evidence for hormone-dependent modification of function and behavior during the menstrual cycle, but little is known about associated short-term structural alterations of the brain. Preliminary studies suggest that a hormone-dependent decline in brain volume occurs in postmenopausal, or women receiving antiestrogens, long term. Advances in serial MR-volumetry have allowed for the accurate detection of small volume changes of the brain. Recently, activity-induced short-term structural plasticity of the brain was demonstrated, challenging the view that the brain is as rigid as formerly believed.

Methodology/Principal Findings

We used MR-volumetry to investigate short-term brain volume changes across the menstrual cycle in women or a parallel 4 week period in men, respectively. We found a significant grey matter volume peak and CSF loss at the time of ovulation in females. This volume peak did not correlate with estradiol or progesterone hormone levels. Men did not show any significant brain volume alterations.

Conclusions/Significance

These data give evidence of short-term hormone-dependent structural brain changes during the menstrual cycle, which need to be correlated with functional states and have to be considered in structure-associated functional brain research.

Effects of glucocorticoids on mood, memory, and the hippocampus. Treatment and preventive therapy

Corticosteroids, such as prednisone and dexamethasone, are commonly prescribed medications that suppress the immune system and decrease inflammation. Common side effects of long-term treatment with corticosteroids include weight gain, osteoporosis, and diabetes mellitus. This paper reviews the literature on psychiatric and cognitive changes during corticosteroid therapy and potential treatment options. Hypomania and mania are the most common mood changes during acute corticosteroid therapy, although depression has also been reported. However, depression is reported to be more common than mania during long-term treatment with corticosteroids. A decline in declarative and working memory is also reported during corticosteroid therapy. Corticosteroids are associated with changes in the temporal lobe, detected by structural, functional, and spectroscopic imaging. The mood and cognitive symptoms are dose dependent and frequently occur during the first few weeks of therapy. Other risk factors are not well characterized. Controlled trials suggest that lithium and phenytoin can prevent mood symptoms associated with corticosteroids. Lamotrigine and memantine also have been shown to reverse, at least partially, the declarative memory effects of corticosteroids. Uncontrolled trials suggest that antipsychotics, anti-seizure medications, and perhaps some antidepressants can also be useful for normalizing mood changes associated with corticosteroids. Thus, both the symptoms and treatment response are similar to those of bipolar disorder. Moreover, corticosteroid-induced mood and cognitive alterations have been shown to be reversible with dose reduction or discontinuation of treatment.

Neurochemical markers of brain damage in cerebrospinal fluid during induction treatment of acute lymphoblastic leukemia in children

BACKGROUND

Central nervous system (CNS) irradiation has been replaced by systemic high-dose methotrexate (MTX) and intrathecal MTX in acute lymphoblastic leukemia treatment due to the risk of late effects. However, treatment without CNS irradiation might also cause brain damage.

PROCEDURE

Cerebrospinal fluid (CSF) was analyzed in 121 patients in an attempt to detect CNS injury. Seventy-three samples were analyzed for neuron-specific enolase (NSE), 108 for glial fibrillary acidic protein (GFAp), 110 for neurofilament protein light chain (NFp), and 70 for ascorbyl radical (AsR). Samples were taken at day 0, 8, 15, and 29 during induction treatment, including intrathecal MTX. Levels at days 8, 15, and 29 were compared with the levels before treatment.

RESULTS

NSE levels were 9.0 (+/-3.5) microg/L (mean (+/-SD)) at day 0, 15.0 (+/-5.3) at day 8 (P < 0.001), 13.6 (+/-4.7) at day 15 (P < 0.001) and 11.1 (+/-4.3) at day 29 (P < 0.001). GFAp were 177 (+/-98) ng/L at day 0, 206 (+/-101) at day 8 (P < 0.001), 200 (+/-106) at day 15 (n.s.) and 228 (+/-137) at day 29 (P < 0.001). NFp were below the detection limit 125 ng/L at day 0 in all 110 CSF samples analyzed, and increased significantly above the detection limit in 6/77 samples at day 8, in 11/84 at day 15 and in 22/91 at day 29. The AsR content did not change significantly.

CONCLUSIONS

Levels of NSE, GFAp, and NFp increased in CSF, which can be interpreted as early signs of brain damage. AsR levels do not show any convincing signs of oxidative stress.

Brain atrophy and cognitive deficits in Cushing's disease

Cushing's disease is associated with brain atrophy and cognitive deficits. Excess glucocorticoids cause retraction and simplification of dendrites in the hippocampus, and this morphological change probably accounts for the hippocampal volume loss. Mechanisms by which glucocorticoids affect the brain include decreased neurogenesis and synthesis of neurotrophic factors, impaired glucose utilization, and increased actions of excitatory amino acids. In this review, the timing, pathology, and pathophysiology of the brain atrophy in Cushing's disease are discussed. The correlation of atrophy with cognitive deficits and its reversibility is also reviewed.

Concentration dependent actions of glucocorticoids on neuronal viability and survival

A growing body of evidence based on experimental data demonstrates that glucocorticoids (GCs) can play a potent role in the survival and death of neurons. However, these observations reflect paradoxical features of GCs, since these adrenal stress hormones are heavily involved in both neurodegenerative and neuroprotective processes. The actual level of GCs appears to have an essential impact in this bimodal action. In the present short review we aim to show the importance of concentration dependent action of GCs on neuronal cell viability and cell survival in the brain. Additionally, we will summarize the possible GC-induced cellular mechanisms at different GC concentrations providing a background for their effect on the fate of nerve cells in conditions that are a challenge to their survival.

Deflazacort induced stronger immunosuppression than expected

Prednisone (PDN) impairs cognitive functioning and brain structures in humans and animals. Deflazacort (DFZ) is a synthetic glucocorticoid claimed to have lesser side effects than prednisone. The objective of this study was to assess whether chronic administration (90 days) of DFZ produces less neuronal degeneration and glial reactivity than PDN. Male Swiss-Wistar rats were studied. Controls received 0.1 ml distilled water orally. The PDN group received prednisone 5 mg per kg per day orally, and the DFZ group received deflazacort 6 mg per kg per day orally. This model had to be assembled in three different occasions due to excess mortality in the DFZ group. A fourth model was assembled using only the DFZ group and slides of water and PDN-exposed rats from a previous study were used as comparators. The index of degenerated neurons and the number and cytoplasmic transformation of astrocytes and microglia cells were evaluated in the prefrontal cortex, CA1, and CA3 hippocampus. The results show that the overall mortality was 49% in the DFZ group, 4.5% in the PDN group, and none of the controls died. Routine necropsy showed infection in multiple organs. The PDN group had two times higher neuronal degeneration in the prefrontal cortex, almost 11 times in CA1, and four times in CA3 hippocampus when compared with controls and DFZ group. Astrocytes reactivity was increased in the PDN- and DFZ-exposed rats compared with controls. The DFZ group showed an average of four times less microgial cells in the three studied regions when compared with controls and the PDN group. In conclusion, it seems that DFZ at the equivalent licensed dose produced a stronger immunosuppressive effect--systemic and in brain tissue--than PDN, but induced less neuronal damage. The immunosuppressant magnitude of DFZ should be further studied in clinical settings.

The impact of medical illness on executive function

Executive function can be defined as one's ability to plan, initiate, sequence, monitor, and inhibit complex goal-directed behaviors. Although executive impairment is generally associated with dementia, recent studies have suggested that patients with chronic diseases, such as hypertension, chronic obstructive pulmonary disease, and diabetes, may also have executive deficits independent of psychiatric comorbidities. Because executive function is associated with functional outcomes, medication compliance, and the capacity to give informed consent, it is important that it be assessed. However, it is the authors' impression that executive function is not adequately assessed in medical settings, despite the availability of reliable measures. This article reviews the impact of medical illness on executive function and discusses practical diagnostic instruments and treatment strategies. The changes in functional status associated with executive impairment as well as pathophysiology and treatment strategies are also discussed.

Measurement of Brain and Spinal Cord Atrophy by Magnetic Resonance Imaging as a Tool to Monitor Multiple Sclerosis

Evaluation of brain and spinal cord atrophy by magnetic resonance imaging (MRI) has become an increasingly important component of understanding the multiple sclerosis (MS) disease process. These destructive aspects of the disease develop early in the disease course. A growing body of data links brain and spinal cord atrophy to clinical impairment more closely than can be linked with conventional measures of overt lesions. Thus, irreversible tissue damage may be a key factor leading to disease progression. In this review, the authors present the proposed mechanisms leading to central nervous system (CNS) atrophy. They describe the available MRI-based techniques to measure regional and global atrophy of the brain and spinal cord. They compare the rate of atrophy among MS phenotypes and summarize the emerging data linking atrophy to neurological and neuropsychological impairment. Finally, they discuss the effect of disease-modifying immunotherapies on the rate of CNS atrophy in patients with MS. Future research to clarify the etiology and pathophysiology of brain and spinal cord atrophy should provide new targets for therapeutic development.

Cognitive function and cerebral assessment in patients who have Cushing's syndrome

Cushing's syndrome (CS) is a relevant model to better understand the effects of glucocorticoid (GC) excess on the human brain. The importance of GC excess on the central nervous system is highlighted by the high prevalence of neuropsychiatric disorders such as depression and cognitive impairment in patients who have CS. In addition, there is a high incidence of apparent diffuse loss of brain volume in patients who have CS. Recent studies indicate at least partial reversibility of these abnormalities following correction of hypercortisolism.

The stress system in the human brain in depression and neurodegeneration

Corticotropin-releasing hormone (CRH) plays a central role in the regulation of the hypothalamic-pituitary-adrenal (HPA)-axis, i.e., the final common pathway in the stress response. The action of CRH on ACTH release is strongly potentiated by vasopressin, that is co-produced in increasing amounts when the hypothalamic paraventricular neurons are chronically activated. Whereas vasopressin stimulates ACTH release in humans, oxytocin inhibits it. ACTH release results in the release of corticosteroids from the adrenal that, subsequently, through mineralocorticoid and glucocorticoid receptors, exert negative feedback on, among other things, the hippocampus, the pituitary and the hypothalamus. The most important glucocorticoid in humans is cortisol, present in higher levels in women than in men. During aging, the activation of the CRH neurons is modest compared to the extra activation observed in Alzheimer's disease (AD) and the even stronger increase in major depression. The HPA-axis is hyperactive in depression, due to genetic factors or due to aversive stimuli that may occur during early development or adult life. At least five interacting hypothalamic peptidergic systems are involved in the symptoms of major depression. Increased production of vasopressin in depression does not only occur in neurons that colocalize CRH, but also in neurons of the supraoptic nucleus (SON), which may lead to increased plasma levels of vasopressin, that have been related to an enhanced suicide risk. The increased activity of oxytocin neurons in the paraventricular nucleus (PVN) may be related to the eating disorders in depression. The suprachiasmatic nucleus (SCN), i.e., the biological clock of the brain, shows lower vasopressin production and a smaller circadian amplitude in depression, which may explain the sleeping problems in this disorder and may contribute to the strong CRH activation. The hypothalamo-pituitary thyroid (HPT)-axis is inhibited in depression. These hypothalamic peptidergic systems, i.e., the HPA-axis, the SCN, the SON and the HPT-axis, have many interactions with aminergic systems that are also implicated in depression. CRH neurons are strongly activated in depressed patients, and so is their HPA-axis, at all levels, but the individual variability is large. It is hypothesized that particularly a subgroup of CRH neurons that projects into the brain is activated in depression and induces the symptoms of this disorder. On the other hand, there is also a lot of evidence for a direct involvement of glucocorticoids in the etiology and symptoms of depression. Although there is a close association between cerebrospinal fluid (CSF) levels of CRH and alterations in the HPA-axis in depression, much of the CRH in CSF is likely to be derived from sources other than the PVN. Furthermore, a close interaction between the HPA-axis and the hypothalamic-pituitary-gonadal (HPG)-axis exists. Organizing effects during fetal life as well as activating effects of sex hormones on the HPA-axis have been reported. Such mechanisms may be a basis for the higher prevalence of mood disorders in women as compared to men. In addition, the stress system is affected by changing levels of sex hormones, as found, e.g., in the premenstrual period, ante- and postpartum, during the transition phase to the menopause and during the use of oral contraceptives. In depressed women, plasma levels of estrogen are usually lower and plasma levels of androgens are increased, while testosterone levels are decreased in depressed men. This is explained by the fact that both in depressed males and females the HPA-axis is increased in activity, parallel to a diminished HPG-axis, while the major source of androgens in women is the adrenal, whereas in men it is the testes. It is speculated, however, that in the etiology of depression the relative levels of sex hormones play a more important role than their absolute levels. Sex hormone replacement therapy indeed seems to improve mood in elderly people and AD patients. Studies of rats have shown that high levels of cumulative corticosteroid exposure and rather extreme chronic stress induce neuronal damage that selectively affects hippocampal structure. Studies performed under less extreme circumstances have so far provided conflicting data. The corticosteroid neurotoxicity hypothesis that evolved as a result of these initial observations is, however, not supported by clinical and experimental observations. In a few recent postmortem studies in patients treated with corticosteroids and patients who had been seriously and chronically depressed no indications for AD neuropathology, massive cell loss, or loss of plasticity could be found, while the incidence of apoptosis was extremely rare and only seen outside regions expected to be at risk for steroid overexposure. In addition, various recent experimental studies using good stereological methods failed to find massive cell loss in the hippocampus following exposure to stress or steroids, but rather showed adaptive and reversible changes in structural parameters after stress. Thus, the HPA-axis in AD is only moderately activated, possibly due to the initial (primary) hippocampal degeneration in this condition. There are no convincing arguments to presume a causal, primary role for cortisol in the pathogenesis of AD. Although cortisol and CRH may well be causally involved in the signs and symptoms of depression, there is so far no evidence for any major irreversible damage in the human hippocampus in this disorder.

Glucocorticoid treatment of brain tumor patients: changes of apparent diffusion coefficient values measured by MR diffusion imaging

Glucocorticoids (GCC) generally are administered to patients with brain tumors to relieve neurological symptoms by decreasing the water content in a peritumoral zone of edema. We hypothesized that diffusion imaging and apparent diffusion coefficient (ADC) values could detect subtle changes of water content in brain tumors and in peritumoral edema after GCC therapy. The study consisted of 13 patients with intra-axial brain tumor, and ADC was measured in the tumor, within peritumoral edema, and in normal white matter remote from the tumor before and after GCC therapy. ADC also was measured in normal white matter in four control patients with no intracranial disease who were treated with GCC for other indications. Conventional MR images showed no visually evident interval change in tumor size or the extent of peritumoral edema in any subject after GCC therapy, which nonetheless resulted in a decrease in mean ADC of 7.0% in tumors (P < 0.05), 1.8% in peritumoral edema (P > 0.05, not significant) and 5.8% in normal white matter (P < 0.05). In patients with no intracranial disease, GCC therapy decreased mean ADC in white matter by 5.4% (P < 0.05). ADC measurement can demonstrate subtle changes in the brain after GCC therapy that cannot be observed by conventional MR imaging. Measurement of ADC proved to be a sensitive means of assessing the effect of GCC therapy, even in the absence of visually discernible changes in conventional MR images.

Correlation of cerebrospinal fluid beta-glucuronidase activity with plasma methotrexate concentrations in leukemic children receiving high-dose methotrexate

BACKGROUND

The activity of lysosomal enzymes is increased in body fluids during inflammation, in which cellular malfunction and cellular death occurs. Because chemotherapy also causes cell malfunction and death, for identifying a neurologic effect, we studied the activity of beta-glucuronidase in the cerebrospinal fluid (CSF) of leukemic children during treatment.

PROCEDURE

The beta-glucuronidase activity in CSF was determined in 13 patients with B-precursor acute lymphoblastic leukemia (ALL) treated with the medium risk arm of ALL Berlin-Frankfurt-Munster (BFM) 95 protocol. Plasma methotrexate (MTX) levels were determined at 24 and 48 hr after the infusion of high-dose (5 g/m(2)/24 hr) MTX (MCA phase).

RESULTS

The mean (SD) beta-glucuronidase activity prior to the onset of chemotherapy was 19.9 (5.6) nmoles/4-methylumbelliferone/ml/hr. No significant changes in activity were noted during the phases of the protocol except of the MCA3. The activity was 24.4 (6.8) on MCA2, 28.4 (9.3) on MCA3, and 24.1 (9.5) on MCA4. The beta-glucuronidase activity was positively correlated with the plasma MTX levels at both 24 hr (r = 0.483, P = 0.006) and 48 hr (r = 0.676, P < 0.0001). No progressive changes were noted during the different phases of the protocol. The greatest beta-glucuronidase activity was measured in two patients with neurotoxicity.

CONCLUSIONS

The beta-glucuronidase activity is increased in the CSF of leukemic children receiving high-dose MTX and particularly in neurotoxicity. It is positively correlated with plasma MTX levels. No cumulative effect of the chemotherapy was observed. The increased beta-glucuronidase activity is most likely due to enzyme leakage through the cell membranes caused mainly by a toxic effect of MTX on the cells of the central nervous system (CNS).

[MRI of central nervous system in a series of 58 systemic lupus erythematosus (SLE) patients with or without overt neuropsychiatric manifestations]

PURPOSE

Central nervous (CNS) involvement in SLE is common and can be evaluated with MRI. The primary goal of this study was to evaluate with high-field MRI the CNS involvement in a series of SLE patients with or without neuropsychiatric symptoms. The secondary goal was to detect a possible relationship between MRI and clinical or biological parameters in SLE.

MATERIALS AND METHODS

We correlated the clinical and biological parameters of 58 patients with a lupus defined according to the American College of Rheumatology criteria, including 30 with neuropsychiatric manifestations with conventional and modern MRI (including diffusion weighted-images, high-resolution 3D T1 weighted-images). The population studied was compared to a group of 18 normal controls.

RESULTS

In 69% of cases, MRI demonstrated involvement of the CNS both in asymptomatic patients (64.3%) and in patients with neuropsychiatric manifestations (73.3%): microembolic signals, cerebral infarctions (associated with the anti-phospholipid syndrome), atrophy, basal ganglia involvement, posterior leucoencephalopathy, subcortical calcification or hemosiderin deposits (T2*), dilated perivascular spaces.

CONCLUSION

MRI with adapted sequences clearly demonstrated the cerebral involvement in approximately 70% of SLE patients with or without neuropsychiatric symptoms.

Brain tissue volume segmentation in patients with anorexia nervosa before and after weight normalization

OBJECTIVE

To examine whether gray and white matter volumes are preferentially reduced and cerebral spinal fluid (CSF) increased with starvation in patients with anorexia nervosa compared with healthy controls and to determine what changes occur with weight normalization.

METHOD

Whole intracranial volumes of patients and controls were segmented into gray matter, white matter, and CSF volumes and results compared. A subgroup of patients were rescanned after weight normalization.

RESULTS

Total white matter and several regional white matter volumes were significantly reduced and total and regional CSF volumes were significantly increased in patients versus controls whereas gray matter was not significantly reduced. Total and regional CSF volumes were significantly decreased in patients upon weight normalization whereas white and gray matter volumes increased.

DISCUSSION

These changes in brain tissue may be related to a variety of pathophysiologic mechanisms. We hypothesize that insulin-like growth factor-1 may be involved.

Prednisone induces cognitive dysfunction, neuronal degeneration, and reactive gliosis in rats

BACKGROUND

High glucocorticoid serum levels and prednisone (PDN) therapy have been associated with depression, posttraumatic stress disorder, and some types of cognitive dysfunction in humans.

OBJECTIVE

The aim of this study was to assess whether chronic (90 days) PDN administration produces disturbance in learning and memory retention associated with neuronal degeneration and cerebral glial changes.

METHODS

Male Wistar rats were studied. Controls received 0.1 ml distilled water vehicle orally. The PDN group was treated orally with 5 mg/kg/d PDN, which is equivalent to moderate doses used in clinical settings. Learning and memory retention were assessed with the Morris water maze. The index of degenerated neurons as well as the number and cytoplasmic transformation of astrocytes and microglia cells were evaluated in the prefrontal cortex and the CA1 hippocampus.

RESULTS

PDN-treated rats showed a significant delay of 20% in learning and memory retention as compared with controls. In addition, in the PDN group, the neuronal degeneration index was two times higher in the prefrontal cortex, and approximately 10 times higher in the CA1 hippocampus, than in control animals. The number and cytoplasmic transformation of astrocytes were also significantly higher in the PDN group than in control animals. In the PDN-treated group, isolectin-B4-labeled microglia cells were higher in the prefrontal cortex but not in the hippocampus.

CONCLUSION

These results suggest that chronic exposure to PDN produces learning and memory impairment, reduces neural viability, and increases glial reactivity in cerebral regions with these cognitive functions.

Cerebral volume changes in multiple sclerosis patients treated with high-dose intravenous methylprednisolone

OBJECTIVE

Multiple sderosis (MS) patients develop varying degrees of cerebral atrophy, which may already begin at disease onset The purpose of this study is to examine the effect of steroid treatment on cerebral volume in MS patients.

METHODS

Thirty-five MS patients participating in a clinical trial of oral interferon beta, which induded monthly MRI, were included in this study. They suffered from an acute relapse and were treated with intravenous methylprednisolone (IV-MP); 13 of the patients were treated with oral prednisolone tapering after IV-MP. The last MRI scan before and the first (and second for oral tapering patients) scan after IV-MP treatment were used for measuring parenchymal fraction (PF) and ventricular fraction (VF). Changes in PF and VF were analysed using Student's t test.

RESULTS

For the total population no significant changes in PF or VF were found. However, the subgroup of patients receiving oral tapering after IV-MP showed changes, compatible with atrophy in both PF and VF, that were significant immediately after IV-MP treatment and still persisted (though not statistically significant anymore) after a mean interval of 30 days. The magnitude of these changes was about the same as the annual change in cerebral volume as reported in natural history studies.

CONCLUSION

Our data indicate that short courses of intravenous steroids (restricted to three or five days) have no major impact, whereas prolonged treatment with oral tapering does significantly affect brain volume. These findings are important for longitudinal studies and clinical trials in which brain volume is used as an outcome measure.

Persistent cognitive impairment following surgical treatment of Cushing's syndrome

Chronic exposure to elevated glucocorticoid (GC) levels in Cushing's syndrome (CS) is associated with deficits in cognitive function. It has already been shown that CS patients scored significantly lower than controls on several aspects of cognitive function (J. Int. Neuropsychol. Soc. 6 (2000) 20). In the present study, 13 subjects who presented with CS were investigated one year after surgical treatment to determine the extent to which the effects of hypercortisolism on cognitive function are reversible. Subjects were evaluated with a battery of tasks, similar to the original battery of a year earlier and including tests of attention, visuospatial processing, memory, reasoning and verbal fluency. Except for one task of visual organization, the results showed little change in performance, suggesting that prolonged exposure to high levels of GC can cause long-lasting deleterious effects on cognitive function. The data suggest that correction of hypercortisolism is not necessarily correlated with short-term improvement in cognitive function.

Structural changes in the brain in depression and relationship to symptom recurrence

Depression is an important public health problem affecting about 15% of the general population; however, little is known about possible changes in the brain that might underlie the disorder. Neuroimaging has been a powerful tool to map actual changes in the brain structure of depressed patients that might be directly related to their symptoms of depression. Some imaging studies of brain structure have shown smaller hippocampal volume with the chronicity of depression correlating to a reduction in volume. Although the meaning of these findings is unclear, other studies have shown increased amygdala volume. Studies have found reductions in volume of the frontal cortex, with some studies showing specific reductions in subregions of the frontal cortex, including the orbitofrontal cortex. Findings of an increase in white matter lesions in elderly patients with depression have been replicated and correlated with late-onset depression, as well as impairments in social and cognitive function. These findings point to alterations in a circuit of brain regions hypothesized to include the frontal cortex, hippocampus, amygdala, striatum, and thalamus, that underlie symptoms of depression.

Long-term neurobehavioral outcomes in children with neuroblastoma and opsoclonus-myoclonus-ataxia syndrome: relationship to MRI findings and anti-neuronal antibodies

OBJECTIVES

Opsoclonus-myoclonus-ataxia (OMA) syndrome affects 2% to 3% of patients with neuroblastoma. This study examined relationships between long-term neurobehavioral outcomes and potential biologic markers of OMA, including chronic changes on magnetic resonance imaging (MRI) brain scanning and prevalence of late antineuronal antibodies.

STUDY DESIGN

Children with neuroblastoma and OMA were identified through medical record review of patients treated at the University of California at San Francisco Medical Center from 1979 to 1999. Eleven patients with a mean follow-up time of 7.6 years underwent standard neurologic, neurocognitive, developmental/behavioral, and academic assessments. Consenting patients underwent MRI brain scanning and a blood draw. Sera were analyzed for the presence of antineuronal immunoreactivity.

RESULTS

Two (18%) patients had no observed neurologic abnormalities, 7 (64%) demonstrated mild deficits, and 2 (18%) had severe neurologic deficits. However, on neurocognitive, behavioral, and academic assessments, 6 (55%) children performed within the average range, 1 (9%) was moderately below average and 4 (36%) had severe cognitive and behavioral deficiencies. Brain MRI in 5 of 5 patients was notable for cerebellar atrophy without supratentorial involvement. Antineuronal activity was detected in sera of 0 of 10 children at follow-up.

CONCLUSIONS

Certain patients with neuroblastoma associated OMA may achieve average-range neurobehavioral function in spite of residual neurologic abnormalities, with suggestion of continued improvement over time. Late cerebellar atrophy appears to be a common finding regardless of neurologic outcome, whereas antineuronal immune reactivity does not appear to be a long-term feature of OMA.

Action of glucocorticoids on survival of nerve cells: promoting neurodegeneration or neuroprotection?

Extensive studies during the past decades provided compelling evidence that glucocorticoids (GCs) have the potential to affect the development, survival and death of neurones. These observations, however, reflect paradoxical features of GCs, as they may be critically involved in both neurodegenerative and neuroprotective processes. Hence, we first address different aspects of the complex role of GCs in neurodegeneration and neuroprotection, such as concentration dependent actions of GCs on neuronal viability, anatomical diversity of GC-mediated mechanisms in the brain and species and strain differences in GC-induced neurodegeneration. Second, the modulatory action of GCs during development and ageing of the central nervous system, as well as the contribution of altered GC balance to the pathogenesis of neurodegenerative disorders is considered. In addition, we survey recent data as to the possible mechanisms underlying the neurodegenerative and neuroprotective actions of GCs. As such, two major aspects will be discerned: (i) GC-dependent offensive events, such as GC-induced inhibition of glucose uptake, increased extracellular glutamate concentration and concomitant elevation of intracellular Ca(2+), decrease in GABAergic signalling and regulation of local GC concentrations by 11 beta-hydroxysteroid dehydrogenases; and (ii) GC-related cellular defence mechanisms, such as decrease in after-hyperpolarization, increased synthesis and release of neurotrophic factors and lipocortin-1, feedback regulation of Ca(2+) currents and induction of antioxidant enzymes. The particular relevance of these mechanisms to the neurodegenerative and neuroprotective effects of GCs in the brain is discussed.

Long-term brain metabolic alterations in exogenous Cushing's syndrome as monitored by proton magnetic resonance spectroscopy

The effects of exogenous Cushing's syndrome on the brain metabolism were investigated by proton magnetic resonance spectroscopy (MRS). Thirteen patients having been treated for 2 to 22 years with prednisone were recruited. On the average, none of the metabolites (NAA, Cr, Cho and mI) were significantly different from those of 40 normal subjects in any of the three regions studied: frontal area, thalamus and temporal area. However, the Cho/H(2)O ratios were found to decrease significantly in the thalamic area as a function of treatment period (-1.3%/year). In the frontal and temporal areas, decreases of the Cho/H(2)O ratios were measured with treatment period but they did not reach statistical significance. Effects on Cho levels can be related to those observed for patients with endogenous Cushing's syndrome and suggest an impairment at the membrane level. The Cho/H(2)O reductions were not found to be dose- or age-dependent. Other metabolite ratios did not vary with treatment period, dose or age.

Secondary partial empty sella syndrome in an elite bodybuilder

The pituitary gland is a hormone-responsive gland and is known to vary in size depending on the hormonal status of the patient and the multifaceted positive and negative feedback hypothalamic-pituitary-gonadal axis. Partial empty sella syndrome with an atrophied pituitary gland is seen in primary neuroendocrinopathies such as growth hormone deficiency, primary hypothyroidism, central diabetes insipidus and hypogonadism. Partial empty sella has also been shown to occur in patients with elevations in intracranial pressure. Secondary partial empty sella syndrome with significant pituitary gland atrophy from negative feedback inhibition of long-term exogenous hormonal use has not been previously reported. We are reporting on a case of partial empty sella syndrome occurring in an elite bodybuilder with a long history of exogenous abuse of growth hormone, testosterone and thyroid hormone. The pathophysiological mechanisms of secondary partial empty sella syndrome from exogenous hormone use and the possibility for elevations in intracranial pressure contributing to this syndrome will be discussed.

MRI findings in neuro-behçet's disease

AIM

To evaluate the pattern and site of involvement in neuro-Behçet's disease (NBD).

MATERIALS AND METHODS

Twenty-one patients with NBD were evaluated. Using 1.5T magnetic resonance imaging (MRI), T1-weighted axial and sagittal images, gadolinium enhanced axial and coronal images and T2-weighted axial images were obtained.

RESULTS

The brainstem, basal ganglia, cerebral white matter, internal capsule, thalamus and spinal cord were involved in eighteen, nine, nine, seven, six and two patients, respectively. In nine patients with cerebral white matter involvement, four had subcortical involvement and three had periventricular involvement, in addition to two patients with focal deep white matter lesions. Among the brainstem lesions, pons involvement was seen in fourteen patients, all had ventrally located lesions, and nine had tegmental involvement. Midbrain involvement was seen in fourteen patients; the cerebral peduncle was involved in 11 of these. Five patients had brainstem atrophy: two cases were demonstrated at initial MRI, the other three cases were seen on follow-up MRI. Pyramidal signs, the most common neurological signs, were demonstrated in fourteen patients. Follow-up MRI was obtained 10 days to 20 months after the initial MRI in eight cases; all showed changes in size, shape and site of involvement. After gadolinium enhancement, thirteen patients demonstrated mottled non-confluent enhancement in the brainstem (eight patients), posterior limb of the internal capsule (three patients), pachymeninges (two patients) and spinal cord (two patients).

CONCLUSION

NBD manifests a reversible course, but chronic NBD may result in brainstem atrophy. Characteristic involvement along the corticospinal tract is well correlated with neurological signs.

The effects of a mild stressor on spontaneous alternation in mice

Adult mice of the C57BL/6J strain were subjected to an acute mild stress at different periods before the choice trial of a spontaneous alternation test. The stressful event was either inescapable (forced exploration in a brightly lit open field) or escapable (temporary entries into an adjacent dark chamber). While unstressed control mice alternated above chance in each condition, mice subjected to inescapable stress did not alternate when forced exposure to the open field occurred during the entire retention interval. The same effect was seen when forced exposure to the open field occurred after a post-forced trial delay period. However, no change in the alternation rate was observed when the inescapable stress occurred before the forced trial, or if the delay intervened between the stressful event and the choice trial. The escapable stressful event had no effect on spontaneous alternation. These results indicate the role of cognitive mediation in the behavioral effects of inescapable stress, causing either a retrieval deficit or neophobia.

An MRI study of temporal lobe structures in men with bipolar disorder or schizophrenia

BACKGROUND

Hippocampal atrophy has been described in postmortem and magnetic resonance imaging studies of schizophrenia. The specificity of this finding to schizophrenia remains to be determined. The neuropathology of bipolar disorder is understudied, and temporal lobe structures have only recently been evaluated.

METHODS

Twenty-four bipolar, 20 schizophrenic, and 18 normal comparison subjects were evaluated using magnetic resonance brain imaging. Image data were acquired using a three-dimensional spoiled GRASS sequence, and brain images were reformatted in three planes. Temporal lobe structures including the amygdala, hippocampus, parahippocampus, and total temporal lobe were measured to obtain volumes for each structure in the three subject groups. Severity of symptoms in both patient groups was assessed at the time the magnetic resonance images were obtained.

RESULTS

Hippocampal volumes were significantly smaller in the schizophrenic group than in both bipolar and normal comparison subjects. Further, amygdala volumes were significantly larger in the bipolar group than in both schizophrenic and normal comparison subjects.

CONCLUSIONS

The results suggest differences in affected limbic structures in patients with schizophrenia and bipolar disorder. These specific neuroanatomic abnormalities may shed light on the underlying pathophysiology and presentation of the two disorders.

Recovery of the brain choline level in treated Cushing's patients as monitored by proton magnetic resonance spectroscopy

In a previous study from our group [A. Khiat, C. Bard, A. Lacroix, J. Rousseau, Y. Boulanger, Brain metabolic alterations in Cushing's syndrome as monitored by proton magnetic resonance spectroscopy, NMR Biomed. 12 (1999) 357-363], proton magnetic resonance spectroscopy (1H MRS) was used to evaluate changes in cerebral metabolites in patients with Cushing's syndrome as compared to normal subjects. Data recorded in the frontal, thalamic and temporal areas demonstrated statistically significant decreases of the Cho/Cr ratios in the frontal and thalamic areas but not in the temporal area for Cushing's syndrome patients. No statistically significant changes in the NAA/Cr ratios were measured in any of the areas studied. In this follow-up study, MRS data are reported for ten patients after correction of hypercortisolism which demonstrate a statistically significant recovery of the choline levels in the frontal and thalamic areas. No variation in the NAA, Cr and mI metabolite ratios relative to H(2)O could be measured. Results are interpreted as an inhibition of the phosphatidylcholine degrading phospholipases by glucocorticoids which disappears after correction of hypercortisolism.

Cerebral atrophy in Cushing's disease

BACKGROUND

Cushing's disease causes significant pathological changes throughout the body as a result of elevated cortisol levels. Very few systematic investigations have focused on the morphologic effects of hypercortisolism on the central nervous system. The validity of using premature cerebral atrophy as a diagnostic tool for Cushing's disease remains unknown.

METHODS

This study includes 63 patients with Cushing's disease who were evaluated and treated at the University of Virginia Medical Center. Radiologists randomly compared these individuals with age- and sex-matched controls in a blinded protocol, assessing the degree of cerebral atrophy on computed tomography and magnetic resonance scans.

RESULTS

Patients with Cushing's disease showed significant premature atrophy when compared with controls. This trend continued after subdividing the groups based on age and duration of symptoms except in the following groups: age greater than 60, duration of symptoms less than 1 year, and symptoms lasting between 4-5 years.

CONCLUSIONS

Excluding the three aforementioned groups, the hypercortisolemic state manifested in patients with Cushing's disease promotes the premature development of cerebral atrophy, which can be identified on routine radiologic imaging and may assist in the clinical diagnosis of the condition.

The psychiatric side effects of corticosteroids

LEARNING OBJECTIVES

Readers will learn the importance of psychiatric symptomatology with corticosteroid drug therapy, especially when combined with other medications.

DATA SOURCES

A brief history of corticosteroid use over the last five decades was complied utilizing MEDLINE and PSYCHOINFO as sources of information which include peer-reviewed research articles, case studies, and relevant reviews in English.

CONCLUSION

Corticosteroids are routinely prescribed for a variety of allergic and immunologic illnesses. Psychiatric side effects from corticosteroids include mania, depression and mood disturbances. Psychiatric symptoms usually occur within the first two weeks of corticosteroid therapy and seem to be dose related. Treatment with lithium or antipsychotics may be helpful. Physicians should carefully monitor patients for psychiatric and cognitive side effects of corticosteroid use.

Brain metabolic alterations in Cushing's syndrome as monitored by proton magnetic resonance spectroscopy

Proton magnetic resonance spectroscopy ((1)H MRS) was used to evaluate changes in cerebral metabolites in 13 patients with Cushing's syndrome (including seven with pituitary corticotroph adenomas and six with primary adrenal disease) as compared to 40 normal subjects. Data were recorded in the frontal, thalamic and temporal areas; quantification of the MRS signals demonstrated a statistically significant decrease of the Cho/Cr ratio in the frontal and thalamic areas but not in the temporal area for patients with Cushing's syndrome. The largest decrease in Cho/Cr was measured in the thalamic area of patients with a Cushing's syndrome secondary to an adrenal disease. No statistically significant changes in the NAA/Cr ratio were measured in any of the areas studied. These results suggest that the quantification of choline levels could be helpful for monitoring the cerebral metabolite alterations in patients with hypercortisolism.