Decreased pituitary volume in patients with bipolar disorder

Enlarged pituitary gland volume: a possible state rather than trait marker of psychotic disorders

BACKGROUND

Enlarged pituitary gland volume could be a marker of psychotic disorders. However, previous studies report conflicting results. To better understand the role of the pituitary gland in psychosis, we examined a large transdiagnostic sample of individuals with psychotic disorders.

METHODS

The study included 751 participants (174 with schizophrenia, 114 with schizoaffective disorder, 167 with psychotic bipolar disorder, and 296 healthy controls) across six sites in the Bipolar-Schizophrenia Network on Intermediate Phenotypes consortium. Structural magnetic resonance images were obtained, and pituitary gland volumes were measured using the MAGeT brain algorithm. Linear mixed models examined between-group differences with controls and among patient subgroups based on diagnosis, as well as how pituitary volumes were associated with symptom severity, cognitive function, antipsychotic dose, and illness duration.

RESULTS

Mean pituitary gland volume did not significantly differ between patients and controls. No significant effect of diagnosis was observed. Larger pituitary gland volume was associated with greater symptom severity (F = 13.61, p = 0.0002), lower cognitive function (F = 4.76, p = 0.03), and higher antipsychotic dose (F = 5.20, p = 0.02). Illness duration was not significantly associated with pituitary gland volume. When all variables were considered, only symptom severity significantly predicted pituitary gland volume (F = 7.54, p = 0.006).

CONCLUSIONS

Although pituitary volumes were not increased in psychotic disorders, larger size may be a marker associated with more severe symptoms in the progression of psychosis. This finding helps clarify previous inconsistent reports and highlights the need for further research into pituitary gland-related factors in individuals with psychosis.

Anterior pituitary gland volume mediates associations between pubertal hormones and changes in transdiagnostic symptoms in youth

The pituitary gland (PG) plays a central role in the production and secretion of pubertal hormones, with documented links to the emergence and increase in mental health symptoms known to occur during adolescence. Although much of the literature has focused on examining whole PG volume, recent findings suggest that there are associations among pubertal hormone levels, including dehydroepiandrosterone (DHEA), subregions of the PG, and elevated mental health symptoms (e.g., internalizing symptoms) during adolescence. Surprisingly, studies have not yet examined associations among these factors and increasing transdiagnostic symptomology, despite DHEA being a primary output of the anterior PG. Therefore, the current study sought to fill this gap by examining whether anterior PG volume specifically mediates associations between DHEA levels and changes in dysregulation symptoms in an adolescent sample ( N = 114, 9 - 17 years, M age = 12.87, SD = 1.88). Following manual tracing of the anterior and posterior PG, structural equation modeling revealed that greater anterior, not posterior, PG volume mediated the association between greater DHEA levels and increasing dysregulation symptoms across time, controlling for baseline dysregulation symptom levels. These results suggest specificity in the role of the anterior PG in adrenarcheal processes that may confer risk for psychopathology during adolescence. This work not only highlights the importance of separately tracing the anterior and posterior PG, but also suggests that transdiagnostic factors like dysregulation are useful in parsing hormone-related increases in mental health symptoms in youth.

Pituitary volumes in patients with adjustment disorder

The pituitary gland plays an important role in the stress response mechanism. Given the direct link between adjustment disorder and stress, we hypothesized that there might be changes in the pituitary gland in these patients. The study comprised a patient group of 19 individuals with adjustment disorder according to the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition, and 18 healthy controls. The mean pituitary gland volumes of the patient group were not statistically significantly different from those of the healthy control group (80.81 ± 1.82 mm3 in patients with adjustment disorder vs. 81.10 ± 7.04 mm3 in healthy controls, with a statistically nonsignificant difference of P > 0.05). This finding is contrary to our previous findings in anxiety-related disorders. In this regard, adjustment disorder is not similar to anxiety-related disorders in terms of pituitary gland volumes. We should also clearly state that our study is a pioneering study and that studies with large samples are needed to support our findings. The limitations of our study can be attributed to the small sample size, the utilization of a cross-sectional design, and the inclusion of patients using psychotropic drugs.

Pituitary Volumes Are Reduced in Patients With Alcohol Use Disorder

AIMS

To determine whether there is a difference in pituitary gland volumes in patients with alcohol use disorder compared to healthy people.

METHODS

The subjects included in the study consisted of 15 individuals who met the criteria for alcohol use disorder according to the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM 5) diagnostic criteria based on the Structured Clinical Interview for DSM 5 and were admitted to Firat University School of Medicine, Department of Psychiatry, or were hospitalized, and 17 healthy controls. The volumes of pituitary were measured in subjects.

RESULTS

Absolute pituitary gland volumes of patients with alcohol use disorder and healthy controls were compared in the analysis performed using the independent samples t-test. The mean volume of the patient group was significantly smaller than the healthy controls (58.02 ± 7.24 mm3 in patients with alcohol use disorder vs. 83.08 ± 12.11 mm3, P < 0.01), a difference which persisted after controlling for age, gender and total brain size.

CONCLUSIONS

Patients with alcohol use disorder in this study had smaller pituitary gland volumes compared to those of healthy control subjects. However, this study has limitations including small sample size and not adjusting for previous or current medication use or current anxiety and depression.

The Morphology of the Pituitary Gland: A Meta-Analysis with Implications for Diagnostic Imaging

The objective of this meta-analysis was to present transparent data on the morphology of the pituitary gland (PG) using the available data in the literature. The main online medical databases, such as PubMed, Embase, Scopus, and Web of Science, were searched to gather all relevant studies regarding PG morphology. The mean overall volume of the PG was found to be 597.23 mm³ (SE = 28.81). The mean overall height of the PG was established to be 5.64 mm (SE = 0.11). The mean overall length of the PG was found to be 9.98 mm (SE = 0.26). In the present study, the PG's overall morphology and morphometric features were analyzed. Our results showed that, on average, females from Asia have the highest volume of PG (706.69 mm³), and males from Europe have the lowest (456.42 mm³). These values are crucial to be aware of because they represent the normal average properties of the PG, which may be used as reference points when trying to diagnose potential pathologies of this gland. Furthermore, the present study's results prove how the PG's size decreases with age. The results of the present study may be helpful for physicians, especially surgeons, performing procedures on the PG.

Pituitary volume in adolescents with non-suicidal self-injury: Preliminary evidence for alterations in pituitary maturation

BACKGROUND

Non-suicidal self-injury (NSSI), typically observed in the context of various mental disorders, represents a highly prevalent and serious problem among adolescents. Based on studies linking NSSI with stress, alterations in hypothalamic-pituitary-adrenal (HPA) axis functioning have been suggested to contribute to the development and maintenance of this behavior. While research has mainly focused on cortisol - the main hormonal output of this system - to our knowledge, no study has examined pituitary gland volume (PGV) - an alternative approach of assessing HPA axis functionality that is less state-dependent - in adolescents engaging in NSSI.

METHODS

Magnetic Resonance Imaging (MRI) was performed among n = 35 adolescents (aged 12-17 years) fulfilling the diagnostic criteria for NSSI disorder according to DSM-5 and n = 31 age-matched healthy controls; PGV was obtained by manual tracing. To test for group differences - our primary aim - a hierarchical linear regression model was computed, controlling for several potential confounding variables. Since adolescence reflects a time period for significant brain development - including changes in PGV - we also tested for an age-dependent group effect. In a second step, we aimed to investigate whether differences in PGV are accounted for by the experience of childhood adversity or psychopathology. Finally, following an exploratory approach, the dimensional association between PGV and various clinical characteristics (e.g., frequency of NSSI) were explored.

RESULTS

No evidence was found for overall volumetric differences between healthy control participants and adolescents engaging in NSSI (p > 0.05) - recognizing that small effect size differences could not be detected in the present study - but group membership significantly interacted with age in predicting PGV (p = 0.02). Particularly, while PGV increased linearly with age in healthy controls (B = 61.39, SE = 14.94, p < 0.01), no corresponding association was found in NSSI patients (B = 16.83, SE = 12.20, p = 0.17). PGV was not related to adverse experiences during childhood and none of the clinical characteristics (e.g., frequency of NSSI) significantly correlated with PGV (p > 0.05).

CONCLUSION

These results provide preliminary evidence for alterations in pituitary maturation in adolescents engaging in NSSI, although replication in longitudinal studies with larger samples is warranted.

Associations between early life stress and anterior pituitary gland volume development - A novel index of long-term hypothalamic-pituitary-adrenal axis functioning

Previous research has established associations between early life stress (ELS) and altered pituitary gland volume (PGV) growth during adolescence. The pituitary gland, however, is composed of an anterior and a posterior lobe with distinct histological and neuroendocrinological properties. While the anterior (but not posterior) pituitary gland is directly involved in the hypothalamic-pituitary-adrenal axis (HPAA) stress response, no studies have examined the effects of ELS on anterior PGV (aPGV). The present study investigated whether previously reported associations between ELS and PGV development during adolescence were driven by aPGV versus posterior PGV (pPGV). Ninety-one adolescents (49 males) were included from a longitudinal, community-based adolescent development study investigating risk for psychopathology. ELS (maternal affective behavior, childhood maltreatment, stressful life events) was assessed during early adolescence. Participants underwent two waves of structural magnetic resonance imaging during mid- and late-adolescence, and aPGV and pPGV were manually traced. Regression analyses showed that childhood maltreatment predicted greater aPGV growth in females. This finding was stronger than that previously reported for PGV. No associations were found between ELS and pPGV development. Neither aPGV nor pPGV changes mediated associations between ELS and psychopathology. Results suggest that ELS may accelerate aPGV (but not pPGV) growth throughout adolescence. Investigating the development of aPGV, rather than PGV, represents a novel approach to studying the effects of stress on HPAA functioning.

Pituitary dysmaturation affects psychopathology and neurodevelopment in 22q11.2 Deletion Syndrome

BACKGROUND

22q11.2 Deletion Syndrome (22q11DS) confers strongly increased genetic risk for multiple psychiatric disorders. Similarly to the general population, rates of psychiatric comorbidity suggest that common disease mechanisms are shared across dimensions of psychopathology. Such pleiotropic disease mechanisms remain however currently unknown. We hypothesized that pituitary dysmaturation, indicative of HPA-axis dysregulation, could correlate to reduced tolerance to daily life stressors and reflect pleiotropic risk factor for psychopathology. Moreover HPA-axis dysregulation could affect atypical cortical and hippocampal development previously described in 22q11DS.

METHODS

Pituitary volume, hippocampal volume and cortical thickness measures were obtained from T1-weighted MRI images in a large longitudinal cohort of youth with 22q11DS (115 subjects, 260 scans, age-range = 5.4-31.6) and healthy controls (151 subjects, 280 scans, age-range = 5.1-32.3). We explored effects of pituitary dysmaturation on tolerance to stress, psychopathology and neurodevelopment employing mixed-models linear regression. Associations of pituitary and cortical development were correlated with the expression pattern of glucocorticoid receptor gene NR3C1 obtained from the Allen-Human-Brain-Atlas.

RESULTS

We observed aberrant pituitary developmental trajectories in 22q11DS, with volumetric reductions emerging by young-adulthood (P = 0.0006). Longitudinal pituitary decline was associated with to reduced tolerance to stress (P = 0.04), higher overall psychopathology (P = 0.0003) and increased risk of psychiatric comorbidity (P = 0.02). Moreover, pituitary decline correlated with blunted growth of the right hippocampus (P = 0.03) and to increased cortical thinning of mostly temporal and orbitofrontal regions mediated by NR3C1 gene expression.

CONCLUSION

Atypical pituitary development could reflect progressive extinction of HPAA due to chronic hyper-activation, in agreement with existing biochemical evidence in 22q11DS. HPAA dysregulation could represent and endophenotype that confers pleiotropic vulnerability to psychopathology and atypical neurodevelopment in 22q11DS.

Neuroanatomical alterations in people with high and low cannabis dependence

OBJECTIVES

We aimed to investigate whether severity of cannabis dependence is associated with the neuroanatomy of key brain regions of the stress and reward brain circuits.

METHODS

To examine dependence-specific regional brain alterations, we compared the volumes of regions relevant to reward and stress, between high-dependence cannabis users (CD+, n = 25), low-dependence cannabis users (CD-, n = 20) and controls (n = 37).

RESULTS

Compared to CD- and/or controls, the CD+ group had lower cerebellar white matter and hippocampal volumes, and deflation of the right hippocampus head and tail.

CONCLUSION

These findings provide initial support for neuroadaptations involving stress and reward circuits that are specific to high-dependence cannabis users.

Smaller Pituitary Volumes in Patients with Delusional Disorder

Introduction:

Delusional disorder shares some clinical characteristics of OCD and hypochondriasis. Delusions compared to obsessions in the OCD and compared to bodily preoccupations in the hypochondriasis are more established beliefs.

Aim:

To measure pituitary volumes in patients with delusional disorder and hypothesized that volumes would be reduced in those patients by a mechanism that we could not account for before for patients with OCD and hypochondriasis.

Methods:

Eighteen patients with delusional disorder and healthy controls were included into the study. Pituitary gland volumes were measured.

Results:

When using independent t test, the mean total pituitary volume was 777.22±241.28 mm³ in healthy controls, while it was 532.11±125.65 mm³ in patients with delusional disorder. The differences in regard to pituitary gland volumes between patients with delusional disorder and healthy control subjects were statistically meaningful (p<0.01), as supported by ANCOVA, with the covariates of age, gender and total brain volumes as covariates.

Conclusion:

We determined that patients with delusional disorder had smaller pituitary volumes compared to those of healthy control subjects.

Pituitary volume in individuals at elevated risk for psychosis: A systematic review and meta-analysis

BACKGROUND

Pituitary volume (PV) abnormalities, representing one of several markers of hypothalamic-pituitary-adrenal (HPA) axis dysregulation, have been observed in psychosis, with variable patterns across illness stages. Typically, enlargements characterise first-episode patients, with reductions observed in those with chronic illness relative to healthy controls. Findings in high-risk populations have been inconsistent, highlighting the need for an updated review of the evidence.

METHODS

We searched PubMed, PsycINFO, and EMBASE for studies examining PV in high-risk [clinical high-risk (CHR), family history of psychosis (FHx), schizotypal personality disorder (SPD), and psychotic-experiences (PEs)] and healthy individuals. Random effects models were used to examine group differences in PV (Hedges g) with stratified analyses and meta-regression employed to investigate the effect of high-risk category, transition status, age, sex, and antipsychotic medication.

RESULTS

Ten studies, yielding 11 effect sizes, were eligible for inclusion. Overall, high-risk individuals had significantly larger PV relative to healthy controls (g = 0.16 [95% CI: 0.01 to 0.32] p = 0.04), despite showing a reduction in whole brain volume (g = -0.17, [95% CI. -0.30 to -0.03] p = 0.020). Individual sub-group analyses for CHR and FHx groups showed no significant differences relative to controls; however, larger PV increases characterised those who later transitioned to psychosis (g = 0.55, [95% CI. 0.06 to 1.04] p = 0.028). Larger effect sizes were positively associated with the proportion of high-risk individuals receiving antipsychotic medication.

CONCLUSIONS

PV enlargements characterise high-risk individuals and are more pronounced among those who later develop psychosis. We provide recommendations for future studies.

Childhood maltreatment, pituitary volume and adolescent hypothalamic-pituitary-adrenal axis - Evidence for a maltreatment-related attenuation

BACKGROUND

Alterations of the development of the hypothalamic-pituitary-adrenal axis (HPAA) have been suggested to be related to experiences of early maltreatment. It has been postulated that early stress (i.e., maltreatment) leads to initial hyperactivation of the HPAA, which subsequently may progress to hypoactivation during the course of adolescence, however empirical studies on this hypothesis are rare. In the current study, we aimed to examine the longitudinal relationships between childhood maltreatment, early adolescent pituitary gland volume (PGV) and mid-adolescent cortisol output in an existing data set to explore the utility of PGV as a measure of HPAA function, and as an indirect test of the attenuation hypothesis.

METHODS

The sample comprised 69 adolescents (30 females), subsampled from a larger longitudinal, community-based study on adolescent development. PGV, as an estimate of chronic childhood HPAA activity, was measured by magnetic resonance imaging during early adolescence (mean age 12.62 ± 0.45 years). Cortisol output was assessed via multiple salivary cortisol measures in mid-adolescence (mean age 15.52 ± 0.39 years). The cortisol awakening response (CAR) was calculated as a measure of HPAA functioning. Retrospective assessment of childhood maltreatment was performed using the Childhood Trauma Questionnaire (CTQ). Regression analyses were conducted to examine whether childhood maltreatment, PGV, and their interaction, predicted mid-adolescent CAR.

RESULTS

No main effect of PGV or maltreatment was found on adolescent CAR. PGV did however significantly interact with childhood maltreatment in predicting the CAR (t = -2.26; p = 0.024). Larger PGV positively predicted lower CAR in the context of relatively high childhood maltreatment (t = 2.032; p = 0.046), but showed no relationship in the context of relatively low maltreatment (t = 0.723; p = 0.472). Maltreatment also interacted with sex, such that (only) in females, higher levels of maltreatment predicted a lower CAR (t = -2.04, p = 0.042).

CONCLUSIONS

In the presence of childhood maltreatment, larger PGV was associated with lower CAR in adolescence, providing support for the application of PGV in studies of HPA axis function. Our finding is consistent with a maltreatment-related attenuation of HPAA functioning that may derive from a stress induced chronic hyperactivation during childhood. Prospective longitudinal studies are now required to further explicate these findings and relationships with psychopathology.

Coping Strategies Mediate the Effect of Stressful Life Events on Schizotypal Traits and Psychotic Symptoms in 22q11.2 Deletion Syndrome

Converging evidence suggests that psychosis emerges from the complex interaction of genetic and environmental factors. Stressful life events (SLEs) play a prominent role in combination with coping strategies and with a dysfunctional hypothalamus-pituitary-adrenal axis (HPAA). It has been proposed that the framework of schizotypy might help disentangle the interaction between genetic and environmental factors in the pathogenesis of psychosis. Similarly, 22q11.2 deletion syndrome (22q11DS) is considered as a genetic model of psychosis vulnerability. However, SLE and coping strategies remain largely unexplored in 22q11DS. Moreover, the HPAA has not been systematically investigated in this population. Here, we explored the correlation between SLE, emotional coping strategies, schizotypal personality traits, subthreshold psychotic symptoms in a sample of 43 healthy controls (HCs) compared with 59 individuals with 22q11DS. In the latter, we also explored the correlation with pituitary volume as estimated from structural magnetic resonance imaging. We found that SLE and negative coping strategies were correlated with schizotypal personality traits in both HCs and 22q11DS, and with psychotic symptoms in the 22q11DS group only, whereas reduced pituitary volume correlated with general psychopathology. Moreover, dysfunctional coping mediated the effect of SLE on schizotypal personality traits and psychotic symptoms in 22q11DS. Our findings recapitulate evidence in nonsyndromic patients and confirm the central role of stress and coping in the pathogenesis of psychosis. More broadly, they highlight the importance of environmental factors in the pathway to psychosis in 22q11DS, suggesting a strong rationale for the implementation of stress and particularly coping-oriented interventions in this population.

Pituitary gland shrinkage in bipolar disorder: The role of gender

BACKGROUND

Hyperactivity of the Hypothalamic-Pituitary-Adrenal Axis (HPAA) has been consistently reported in mood disorders. However, only few studies investigated the Pituitary gland (PG) in Bipolar Disorder (BD) and the results are so far contrasting. Therefore, the aim of this study is to explore the integrity of the PG as well as the role of gender and the impact of clinical measurements on this structure in a sample of BD patients compared to healthy controls (HC).

METHODS

34 BD patients and 41 HC underwent a 1.5 T MRI scan. PG volumes were manually traced for all subjects. Psychiatric symptoms were assessed by means of the Brief Psychiatry Rating Scale, the Hamilton Depression Rating Scale and the Bech Rafaelsen Mania Rating Scale.

RESULTS

We found decreased PG volumes in BD patients compared to HC (F = 24.9, p < 0.001). Interestingly, after dividing the sample by gender, a significant PG volume decrease was detected only in female BD patients compared to female HC (F = 9.1, p < 0.001), but not in male BD compared to male HC (F = -0.12, p = 0.074). No significant correlations were observed between PG volumes and clinical variables.

CONCLUSIONS

Our findings suggest that BD patients have decreased PG volumes, probably due to the long-term hyperactivity of the HPAA and to the consequent strengthening of the negative feedback control towards the PG volume itself. This alteration was particularly evident in females, suggesting a role of gender in affecting PG volumes in BD. Finally, the absence of significant correlations between PG volumes and clinical variables further supports that PG disruption is a trait feature of BD, being independent of symptoms severity and duration of treatment.

Pituitary gland in Bipolar Disorder and Major Depression: Evidence from structural MRI studies: Special Section on "Translational and Neuroscience Studies in Affective Disorders". Section Editor, Maria Nobile MD, PhD. This Section of JAD focuses on the relevance of translational and neuroscience studies in providing a better understanding of the neural basis of affective disorders. The main aim is to briefly summarise relevant research findings in clinical neuroscience with particular regards to specific innovative topics in mood and anxiety disorders

BACKGROUND

The function of the hypothalamo-pituitary-adrenal axis (HPA) has been widely investigated in mood disorders based on its role in regulating stress response. Particularly, Magnetic Resonance Imaging (MRI) reports have explored pituitary gland (PG) in both bipolar disorder (BD) and major depressive disorder (MDD). In this context, the present review summarizes the results from MRI studies with the final aim of commenting on the presence of common or distinct PG structural alterations between these two disabling illnesses.

METHODS

A bibliographic search on PUBMED of all MRI studies exploring PG volumes in BD and MDD as well as first-degree relatives (RELs) from 2000 up to October 2016 was performed.

RESULTS

Following the screening process of the available literature it can be said that a) PG enlargement has been found in both BD and MDD, therefore potentially representing a common neurobiological marker characterizing mood disorders, and b) PG volumes are moderated by age and sex in both illnesses, although the direction and the extent of this moderation are still not fully clear.

LIMITATIONS

Few MRI studies with heterogeneous results.

CONCLUSIONS

These hypotheses must be taken with caution especially because the heterogeneity of the results of the studies reviewed does not allow for a definite answer about the role of PG in affective disorders. Therefore, larger longitudinal studies investigating PG volumes in BD and MDD patients at the early phases of the illness, by considering females and males separately, are needed to further corroborate these findings.

A Comparative Study of Pituitary Volume Variations in MRI in Acute Onset of Psychiatric Conditions

INTRODUCTION

The growing belief that endocrine abnormalities may underlie many mental conditions has led to increased use of imaging and hormonal assays in patients attending to psychiatric OPDs. People who are in an acute phase of a psychiatric disorder show Hypothalamic Pituitary Adrenal (HPA) axis hyperactivity, but the precise underlying central mechanisms are unclear.

AIM

To assess the pituitary gland volume variations in patients presenting with new onset acute psychiatric illness in comparison with age and gender matched controls by using MRI.

MATERIALS AND METHODS

The study included 50 patients, with symptoms of acute psychiatric illness presenting within one month of onset of illness and 50 age and gender matched healthy controls. Both patients and controls were made to undergo MRI of the Brain. A 0.9 mm slices of entire brain were obtained by 3 dimensional T1 weighted sequence. Pituitary gland was traced in all sagittal slices. Anterior pituitary and posterior pituitary bright spot were measured separately in each slice. Volume of the pituitary (in cubic centimetre- cm³) was calculated by summing areas. Significance of variations in pituitary gland volumes was compared between the cases and controls using Analysis of Covariance (ANOVA).

RESULTS

There were significantly larger pituitary gland volumes in the cases than the controls, irrespective of psychiatric diagnosis (ANOVA, f=15.56; p=0.0002). Pituitary volumes in cases were 15.36% (0.73 cm³) higher than in controls.

CONCLUSION

There is a strong likelihood of HPA axis overactivity during initial phase of all mental disorders along with increased pituitary gland volumes. Further studies including hormonal assays and correlation with imaging are likely to provide further insight into neuroanatomical and pathological basis of psychiatric disorders.

Alteration of the brain morphology and the response to the acute stress in the recombinant mouse lines with different predisposition to catalepsy

Catalepsy is an inability to correct an externally imposed awkward posture; it is associated with schizophrenia and depression in human. We created new recombinant B6.CBA-D13Mit76C and B6.CBA-D13Mit76B mouse lines on the C57Bl/6 genome, carrying the 102.73-110.56Mbp fragment of chromosome 13 derived from the catalepsy-prone CBA strain and catalepsy-resistant C57BL/6 strain, respectively. We compared the behavior and brain morphology (11.7T BioSpec 117/16 USR tomograph, Germany) in these lines. The effects of acute emotional stress on corticosterone's level in the blood and mRNA expression of Bdnf and Arc genes in the brain were investigated. The B6.CBA-D13Mit76B mice were non-cataleptic, while about 17% of B6.CBA-D13Mit76C mice demonstrated catalepsy-like immobility. No difference between these lines was revealed in the open field and social interaction tests. In the Morris water maze test, both lines effectively found the platform on the fourth day; however B6.CBA-D13Mit76B mice achieved significantly better results than cataleptic-prone animals. B6.CBA-D13Mit76C mice were characterized by decreased volume of the total brain and reduced sizes of striatum, cerebellum and pituitary gland. The both lines showed the similar basal and stress-induced levels of corticosterone, while the brain expression of Bdnf and Arc genes was more vulnerable to stress in the catalepsy-prone B6.CBA-D13Mit76C line.

Pituitary gland volume and psychosocial stress among children at elevated risk for schizophrenia

BACKGROUND

Pituitary volume enlargements have been observed among individuals with first-episode psychosis. These abnormalities are suggestive of hypothalamic-pituitary-adrenal (HPA) axis hyperactivity, which may contribute to the development of psychosis. However, the extent to which these abnormalities characterize individuals at elevated risk for schizophrenia prior to illness onset is currently unclear, as volume increases, decreases and no volume differences have all been reported relative to controls. The current study aimed to determine whether antipsychotic-naive, putatively at-risk children who present multiple antecedents of schizophrenia (ASz) or a family history of illness (FHx) show pituitary volume abnormalities relative to typically developing (TD) children. An additional aim was to explore the association between pituitary volume and experiences of psychosocial stress.

METHOD

ASz (n = 30), FHx (n = 22) and TD (n = 32) children were identified at age 9-12 years using a novel community-screening procedure or as relatives of individuals with schizophrenia. Measures of pituitary volume and psychosocial stress were obtained at age 11-14 years.

RESULTS

Neither ASz nor FHx children showed differences in pituitary volume relative to TD children. Among FHx children only, pituitary volume was negatively associated with current distress relating to negative life events and exposure to physical punishment.

CONCLUSIONS

The lack of pituitary volume abnormalities among ASz and FHx children is consistent with our previous work demonstrating that these children are not characterized by elevated diurnal cortisol levels. The findings imply that these biological markers of HPA axis hyperactivity, observed in some older samples of high-risk individuals, may emerge later, more proximally to disease onset.

Pituitary volume and clinical trajectory in young relatives at risk for schizophrenia

BACKGROUND

Stress and vulnerability likely interact to play a major role in psychosis. While much has been written about the neural diathesis-stress model in psychosis and its clinical risk states, little is known about HPA axis biomarkers in non-help-seeking individuals at familial high risk (FHR). We sought to prospectively measure pituitary volume (PV) in adolescents and young adults at FHR for schizophrenia and to follow their emerging sub-clinical psychotic symptoms and clinical trajectories.

METHOD

Forty healthy controls and 38 relatives of patients with schizophrenia or schizoaffective disorder were identified in Pittsburgh, USA. PV was derived from baseline 1.5 T magnetic resonance imaging. Chapman's schizotypy scales were acquired at baseline, and structured clinical interviews for DSM-IV-TR Axis I diagnoses were attempted annually for up to 3 years.

RESULTS

Seven individuals converted to psychosis. PV did not differ between FHR and control groups overall. Within the FHR group, PV was positively correlated with Chapman's positive schizotypy (Magical Ideation and Perceptual Aberration) scores, and there was a significant group × PV interaction with schizotypy. PV was significantly higher in FHR subjects carrying any baseline Axis I diagnosis (p = 0.004), and higher still in individuals who went on to convert to psychosis (p = 0.0007).

CONCLUSIONS

Increased PV is a correlate of early positive schizotypy, and may predict trait vulnerability to subsequent psychosis in FHR relatives. These preliminary findings support a model of stress-vulnerability and HPA axis activation in the early phases of psychosis.

Pituitary volumes of the patients with borderline personality disorder are not changed

Although it has important relationships with psychiatric symptoms via the hypothalamic-pituitary-adrenal axis, there have been limited investigations of pituitary neuroimaging in psychiatric disorder. Moreover, there have been no studies of borderline personality disorder. In the present investigation, we examined pituitary gland volumes in patients with borderline personality disorder. Seventeen right-handed female patients with borderline personality disorder, selected among the patients who had presented to Firat University School of Medicine Department of Psychiatry outpatient and inpatient clinics, and the same number of healthy control subjects were included in the present investigation. Pituitary gland volumes were manually detected. The results demonstrated that the mean volumes of the gland of the patients with borderline personality disorder were not significantly different than those of healthy control subjects (mean volume of 0.79 cm3 in the patient group, with a value of SD±0.11 and 0.81 cm3 in the healthy control group, with a value of SD±0.23; t=-0.21; p>0.05).

Subcortical volumes differentiate Major Depressive Disorder, Bipolar Disorder, and remitted Major Depressive Disorder

Subcortical gray matter regions have been implicated in mood disorders, including Major Depressive Disorder (MDD) and Bipolar Disorder (BD). It is unclear, however, whether or how these regions differ among mood disorders and whether such abnormalities are state- or trait-like. In this study, we examined differences in subcortical gray matter volumes among euthymic BD, MDD, remitted MDD (RMD), and healthy (CTL) individuals. Using automated gray matter segmentation of T1-weighted MRI images, we estimated volumes of 16 major subcortical gray matter structures in 40 BD, 57 MDD, 35 RMD, and 61 CTL individuals. We used multivariate analysis of variance to examine group differences in these structures, and support vector machines (SVMs) to assess individual-by-individual classification. Analyses yielded significant group differences for caudate (p = 0.029) and ventral diencephalon (VD) volumes (p = 0.003). For the caudate, both the BD (p = 0.004) and the MDD (p = 0.037) participants had smaller volumes than did the CTL participants. For the VD, the MDD participants had larger volumes than did the BD and CTL participants (ps < 0.005). SVM distinguished MDD from BD with 59.5% accuracy. These findings indicate that mood disorders are characterized by anomalies in subcortical gray matter volumes and that the caudate and VD contribute uniquely to differential affective pathology. Identifying abnormalities in subcortical gray matter may prove useful for the prevention, diagnosis, and treatment of mood disorders.

Pituitary gland volume in at-risk mental state for psychosis: a longitudinal MRI analysis

INTRODUCTION

Pituitary enlargement has been reported in individuals with schizophrenic psychosis or an at-risk mental state for psychosis (ARMS). In a previous study, our group could show pituitary volume increase in first episode and ARMS patients with later transition to psychosis (ARMS-T). However, there are no longitudinal studies on this issue so far. We therefore examined longitudinally whether transition to psychosis would be accompanied by a further increase of pituitary volume in antipsychotic-naïve ARMS patients.

METHODS

Magnetic resonance imaging (MRI) data were acquired from 23 antipsychotic-naïve individuals with an ARMS. Ten subjects developed psychosis (ARMS-T) and 13 did not (ARMS-NT). ARMS-T were re-scanned after the onset of psychosis, and ARMS-NT were re-scanned at the end of the study period.

RESULTS

There was no significant difference of the pituitary volume between ARMS-T and ARMS-NT in our sample, and there were no significant pituitary volume changes over time. Discussion Longitudinally, we could not detect any further volumetric changes in the pituitary volume with transition to psychosis.

CONCLUSIONS

This, together with the result of our previous study, could indicate that the perceived level of stress in ARMS patients is constantly high from very early onward.

Early life stress alters pituitary growth during adolescence-a longitudinal study

The pituitary gland is integral in mediating the stress-response via its role in hypothalamic-pituitary-adrenal (HPA) axis function. Pituitary gland volume (PGV) is altered in stress-related psychopathology, and one study to date has shown stress to be associated with age-related PGV change during adolescence. The current study investigated the effects of a number of different types of early life (i.e., childhood and adolescent) stress (including childhood maltreatment, stressful life events, and maternal affective behavior) on PGV development from mid- to late adolescence using a longitudinal design. The influence of PGV development on depressive and anxiety symptoms was also investigated. Ninety one (49 male) adolescents took part in mother-child dyadic interaction tasks when they were approximately 12 years old, reported on childhood maltreatment and stressful life events when they were approximately 15 years old, and underwent two waves of structural magnetic resonance imaging (MRI) scans, when they were approximately 16 and 19 years old. Results revealed that childhood maltreatment predicted accelerated PGV development in females, and maternal dysphoric behavior predicted accelerated PGV development in the whole sample. PGV development was not associated with depressive or anxiety symptoms. These results suggest an effect of early life stress on altered HPA axis function across mid- to late adolescence. Further research is required to assess functional implications and whether these changes might be associated with risk for subsequent psychopathology.

Brain Structural Effects of Antidepressant Treatment in Major Depression

Depressive disorder is a very frequent and heterogeneous syndrome. Structural imaging techniques offer a useful tool in the comprehension of neurobiological alterations that concern depressive disorder. Altered brain structures in depressive disorder have been particularly located in the prefrontal cortex (medial prefrontal cortex and orbitofrontal cortex, OFC) and medial temporal cortex areas (hippocampus). These brain areas belong to a structural and functional network related to cognitive and emotional processes putatively implicated in depressive symptoms. These volumetric alterations may also represent biological predictors of response to pharmacological treatment. In this context, major findings of magnetic resonance (MR) imaging, in relation to treatment response in depressive disorder, will here be presented and discussed.

Pituitary gland volumes in bipolar disorder

BACKGROUND

Bipolar disorder has been associated with increased Hypothalamic-Pituitary-Adrenal axis function. The mechanism is not well understood, but there may be associated increases in pituitary gland volume (PGV) and these small increases may be functionally significant. However, research investigating PGV in bipolar disorder reports mixed results. The aim of the current study was twofold. First, to assess PGV in two novel samples of patients with bipolar disorder and matched healthy controls. Second, to perform a meta-analysis comparing PGV across a larger sample of patients and matched controls.

METHODS

Sample 1 consisted of 23 established patients and 32 matched controls. Sample 2 consisted of 39 medication-naïve patients and 42 matched controls. PGV was measured on structural MRI scans. Seven further studies were identified comparing PGV between patients and matched controls (total n; 244 patients, 308 controls).

RESULTS

Both novel samples showed a small (approximately 20mm(3) or 4%), but non-significant, increase in PGV in patients. Combining the two novel samples showed a significant association of age and PGV. Meta-analysis showed a trend towards a larger pituitary gland in patients (effect size: .23, CI: -.14, .59).

LIMITATIONS

While results suggest a possible small difference in pituitary gland volume between patients and matched controls, larger mega-analyses with sample sizes greater even than those used in the current meta-analysis are still required.

CONCLUSIONS

There is a small but potentially functionally significant increase in PGV in patients with bipolar disorder compared to controls. Results demonstrate the difficulty of finding potentially important but small effects in functional brain disorders.

Pituitary gland in psychiatric disorders: a review of neuroimaging findings

In this paper, it was reviewed neuroimaging results of the pituitary gland in psychiatric disorders, particularly schizophrenia, mood disorders, anxiety disorders, and somatoform disorders. The author made internet search in detail by using PubMed database including the period between 1980 and 2012 October. It was included in the articles in English, Turkish and French languages on pituitary gland in psychiatric disorders through structural or functional neuroimaging results. After searching mentioned in the Methods section in detail, investigations were obtained on pituitary gland neuroimaging in a variety of psychiatric disorders. There have been so limited investigations on pituitary neuroimaging in psychiatric disorders including major psychiatric illnesses like schizophrenia and mood disorders. Current findings are so far from the generalizability of the results. For this reason, it is required to perform much more neuroimaging studies of pituitary gland in all psychiatric disorders to reach the diagnostic importance of measuring it.

Sex-specific prediction of hypothalamic-pituitary-adrenal axis activity by pituitary volume during adolescence: a longitudinal study from 12 to 17 years of age

OBJECTIVE

To investigate the longitudinal relationship between pituitary gland volume (PGV) and parameters of hypothalamic-pituitary-adrenal axis (HPAA) functioning during adolescence.

METHODS

Participants were 49 adolescents (19 girls and 30 boys) selected from a larger longitudinal, population-based study of adolescent development. Assessments were conducted at three time points (S1, S2 and S3). MRI sessions were at S1 (age: M=12.62, SD=0.45 years) and S3 (M=16.48, SD=0.53 years) and multiple assessments of salivary cortisol were undertaken at S2 (M=15.51, SD=0.35 years). PGV was measured via previously validated manual tracing methods, and the cortisol awakening response (CAR) and diurnal slope (DSL) were used as indices of HPAA functioning.

RESULTS

A significant sex-linked interaction was found for PGV at S1 predicting both CAR (p=0.025) and DSL (p=0.009) at S2. Specifically, PGV at S1 significantly predicted CAR (p=0.033) and DSL (p=0.010) in boys only, with no significant results found for girls. Neither CAR nor DSL at S2 predicted growth of PGV from S1 to S3.

CONCLUSIONS

PGV in early adolescence predicted HPAA functioning in mid-adolescent boys but not in girls. The results suggest a significant influence of sex-specific development on the relationship between PGV and HPAA activity and reactivity. The findings have potential implications for understanding and interpreting sex-linked and stress related clinical disorders that emerge during mid-to-late adolescence.

Increased pituitary volume in subjects at risk for psychosis and patients with first-episode schizophrenia

AIM

Enlarged pituitary gland has been reported in schizophrenia, possibly reflecting hypothalamic-pituitary-adrenal hyperactivity. The aim of the present study was to examine whether individuals at risk of psychosis also have similar changes.

METHODS

Magnetic resonance imaging was used to examine the pituitary volume in 22 individuals with at-risk mental state (ARMS; 11 male, 11 female), 64 first-episode patients with schizophrenia (FESz; 37 male, 27 female), and 86 healthy controls. The control subjects were divided into age- and gender-matched controls for ARMS (11 male, 11 female) and FESz (37 male, 27 female).

RESULTS

Both the ARMS and FESz groups had a larger pituitary volume compared with matched controls, but no difference was found between the ARMS and FESz subjects. There was no association between the pituitary volume and clinical variables (symptommeasures at scanning, daily dosage or duration of antipsychotic medication) in either clinical group. The pituitary volume did not differ significantly between the ARMS individuals who later developed schizophrenia (n = 5) and those who did not (n = 17). The pituitary volume was larger in women than in men for all diagnostic groups.

CONCLUSION

The finding of increased pituitary volume in both ARMS and FESz subjects may reflect a common vulnerability to stress in early psychosis. Further work in a larger ARMS sample is required to examine the possible relationship between pituitary volume and emergence of psychosis.

Missing and Possible Link between Neuroendocrine Factors, Neuropsychiatric Disorders, and Microglia

Endocrine systems have long been suggested to be one of the important factors in neuropsychiatric disorders, while the underlying mechanisms have not been well understood. Traditionally, neuropsychiatric disorders have been mainly considered the consequence of abnormal conditions in neural circuitry. Beyond the neuronal doctrine, microglia, one of the glial cells with inflammatory/immunological functions in the central nervous system (CNS), have recently been suggested to play important roles in neuropsychiatric disorders. However, the crosstalk between neuroendocrine factors, neuropsychiatric disorders, and microglia has been unsolved. Therefore, we herein introduce and discuss a missing and possible link between these three factors; especially highlighting the following hormones; (1) Hypothalamic-Pituitary-Adrenal (HPA) axis-related hormones such as corticotropin-releasing hormone (CRH) and glucocorticoids, (2) sex-related hormones such as estrogen and progesterone, and (3) oxytocin. A growing body of evidence has suggested that these hormones have a direct effect on microglia. We hypothesize that hormone-induced microglial activation and the following microglia-derived mediators may lead to maladaptive neuronal networks including synaptic dysfunctions, causing neuropsychiatric disorders. Future investigations to clarify the correlation between neuroendocrine factors and microglia may contribute to a novel understanding of the pathophysiology of neuropsychiatric disorders.

Pituitary volume in schizophrenia spectrum disorders

INTRODUCTION

There is converging evidence supporting hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis in schizophrenia spectrum disorders (SSD), such as schizotypal personality disorder (SPD), first-episode schizophrenia (FESZ) and chronic schizophrenia (CHSZ). Such an aberrant HPA activity might have volumetric consequences on the pituitary gland. However, previous magnetic resonance imaging (MRI) studies assessing pituitary volume (PV) in SSD are conflicting. The main objective of this study was to examine further PV in SSD.

METHODS

PV were manually traced on structural MRIs in 137 subjects, including subjects with SPD (n = 40), FESZ (n = 15), CHSZ (n = 15), and HC (n = 67). We used an ANCOVA to test PV between groups and gender while controlling for inter-subject variability in age, years of education, socioeconomic status, and whole brain volume.

RESULTS

Overall, women had larger PV than men, and within the male sample all SSD subjects had smaller PV than HC, statistically significant only for the SPD group. In addition, dose of medication, illness duration and age of onset were not associated with PV.

CONCLUSION

Chronic untreated HPA hyperactivity might account for smaller PV in SPD subjects, whereas the absence of PV changes in FESZ and CHSZ patients might be related to the normalizing effects of antipsychotics on PV. SPD studies offer a way to examine HPA related alterations in SSD without the potential confounds of medication effects.

Enhancing synaptic plasticity and cellular resilience to develop novel, improved treatments for mood disorders

There is mounting evidence that recurrent mood disorders - once considered “good prognosis diseases”- are, in fact, often very severe and life-threatening illnesses. Furthermore, although mood disorders have traditionally been conceptualized as neurochemical disorders, there is now evidence from a variety of sources demonstrating regional reductions in central nervous system (CNS) volume, as well as reductions in the numbers and/or sizes ofglia and neurons in discrete brain areas. Although the precise cellular mechanisms underlying these morphometric changes remain to be fully elucidated, the data suggest that mood disorders are associated with impairments of synaptic plasticity and cellular resilience. In this context, it is noteworthy that there is increasing preclinical evidence that antidepressants regulate the function of the glutamatergic system. Moreover, although clearly preliminary, the available clinical data suggest that attenuation of N-methyl-D-aspartate (NMDA) function has antidepressant effects. Recent preclinical and clinical studies have shown that signaling pathways involved in regulating cell survival and cell death are long-term targets for the actions of antidepressant agents. Antidepressants and mood stabilizers indirectly regulate a number of factors involved in cell survival pathways, including cyclic adenosine monophosphate (cAMP) response element binding protein (CREB), brain-derived neurotrophic factor (BDNF), the antiapoptotic protein bcl-2, and mitogen-activated protein (MAP) kinases, and may thus bring about some of their delayed long-term beneficial effects via underappreciated neurotrophic effects. There is much promise for the future development of treatments that more directly target molecules in critical CNS signaling pathways regulating synaptic plasticity and cellular resilience. These will represent improved long-term treatments for mood disorders.

Pituitary volumes are reduced in patients with somatization disorder

OBJECTIVE

Despite of the suggested physiological relationship between somatoform disorder and disturbances in HPA axis function no volumetric study of pituitary volumes in somatization disorder has been carried out. Therefore, we aimed to use structural MRI to evaluate the pituitary volumes of the patients with somatization disorder.

METHODS

Eighteen female patients with somatization disorder according to DSM-IV and same number of healthy controls were included into the study. All subjects were scanned using a 1.5-T General Electric (GE; Milwaukee, USA) scanner. Pituitary volume measurements were determined by using manuallly tracings according to standard antomical atlases.

RESULTS

It was found significantly smaller pituitary volumes of the whole group of somatization patients compared to healthy (t=-3.604, p=0.001). ANCOVA predicting pituitary volumes demonstrated a significant main effect of diagnostic group (F=13.530, p<0.001) but TBV (F=1.924, p>0.05) or age (F=1.159, p>0.05). It was determined that there was no significant correlation between smaller pituitary volumes and the duration of illness (r=0.16, p>0.05) in the patient group.

CONCLUSION

In conclusion, we suggest that the patients with somatization disorder might have significantly smaller pituitary volumes compared to healthy control subjects.

Pituitary volume mediates the relationship between pubertal timing and depressive symptoms during adolescence

Early timing of puberty (i.e., advanced pubertal maturation relative to peers) has been linked to the onset of depressive symptoms during the early adolescent phase. However, the precise neurobiological mechanisms linking early pubertal timing to adolescent depressive symptoms are not clear. We investigated whether the volume of the pituitary gland, a key component of the hypothalamic-pituitary-gonadal (HPG) and hypothalamic-pituitary-adrenal (HPA) axes, mediated the relationship between pubertal timing and depressive symptoms in 155 adolescents (72 females) both cross-sectionally and longitudinally. At baseline (M age 12.7, SD 0.5 years), early pubertal timing predicted larger pituitary gland volume and higher depressive symptoms (especially for girls), but there was no mediation effect. Longitudinally, however, larger pituitary gland volume at baseline was found to mediate the relationship between early pubertal timing and increased depressive symptoms over time (M follow-up period=2.57 years, SD=0.26) for both boys and girls. Our findings suggest that neurobiological mechanisms are partly responsible for the link between early pubertal timing and depressive symptoms in adolescents. We speculate that an enlarged pituitary gland in adolescents with early pubertal timing might be associated with hyperactivation of the hormonal stress response, leading to increased susceptibility to environmental stressors, and subsequent development of depressive symptoms. Given the well-established relationship between increasing depressive symptoms in adolescence and later disorder, these findings have implications for targeted prevention and early intervention strategies for depressive disorders in adolescence.

Pituitary volume, stress reactivity and genetic risk for psychotic disorder

BACKGROUND

Hypothalamic-pituitary-adrenal (HPA) axis hyperactivity, associated with increased pituitary volume, may mediate observed alterations in stress reactivity in patients with psychotic disorder. We examined the association between pituitary volume, real-life stress reactivity and genetic liability for psychotic disorder.

METHOD

Pituitary volumes were derived from magnetic resonance imaging (MRI) scans of 20 patients with psychotic disorder, 37 non-psychotic siblings of these patients, and 32 controls. The Experience Sampling Method (ESM) was used to measure emotional stress reactivity [changes in negative affect (NA) associated with daily life stress] in the three groups, and biological stress reactivity (changes in cortisol associated with daily life stress) in siblings and controls. Interactions between group, stress and pituitary volume in models of NA and cortisol were examined.

RESULTS

Groups did not differ in pituitary volume. Patients showed significantly higher emotional stress reactivity than siblings and controls. In addition, emotional stress reactivity increased with increasing pituitary volume to a greater degree in patients than in controls and siblings. Siblings had higher cortisol levels than controls but did not show increased cortisol reactivity to stress. There was no interaction between pituitary volume, stress and group in the model of cortisol.

CONCLUSIONS

Higher pituitary volume was associated with increased emotional stress reactivity in patients with psychotic disorder, siblings and controls. The association was significantly stronger in the patient group, suggesting a process of progressive sensitization mediating clinical outcome.

Longitudinal MRI study of the pituitary volume in chronic schizophrenia: a preliminary report

This longitudinal MRI study investigated the pituitary volume in 17 patients with chronic schizophrenia and 17 matched controls. In contrast to previous findings of pituitary expansion during the first episode of schizophrenia, the chronic patients showed non-significant mild pituitary atrophy, suggesting that the pituitary volume changes differently at different illness stages.

Structural studies of the hypothalamus and its nuclei in mood disorders

A large body of evidence indicates that the hypothalamus is involved in pathogenetic mechanisms of mood disorders. It has been suggested that functional abnormalities of the hypothalamus are associated with structural hypothalamic changes. Structural neuroimaging allows in vivo investigation of the hypothalamus that may shed light on the underlying pathogenetic mechanisms of unipolar and bipolar disorder. Clearly, the detection of subtle structural cerebral changes depends on the limitations of the neuroimaging technique used. Making a comprehensive database search, we reviewed the literature on hypothalamic macrostructure in affective disorders, addressing the specific question of what structural magnetic resonance imaging might be expected to show. Studies with convincing methodology, although rare, suggest a global volume decrease in the hypothalamus in affective disorders, a decrease which is not shown by the two specific nuclei investigated, the paraventricular and supraoptic nuclei. We discuss the implications of these findings and provide directions for future research.

Magnetic resonance imaging studies in unipolar depression: systematic review and meta-regression analyses

Previous meta-analyses of structural MRI studies have shown diffuse cortical and sub-cortical abnormalities in unipolar depression. However, the presence of duplicate publications, recruitment of particular age groups and the selection of specific regions of interest means that there is uncertainty about the balance of current research. Moreover, the lack of systematic exploration of highly significant heterogeneity has prevented the generalisability of finding. A systematic review and random-effects meta-analysis was carried out to estimate effect sizes. Possible publication bias, and the impact of various study design characteristics on the magnitude of the observed effect size were systematically explored. The aim of this study was 1) to include structural MRI studies systematically comparing unipolar depression with bipolar disorder and healthy volunteers; 2) to consider all available structures of interest without specific age limits, avoiding data duplication, and 3) to explore the influence of factors contributing to the measured effect sizes systematically with meta-regression analyses. Unipolar depression was characterised by reduced brain volume in areas involved in emotional processing, including the frontal cortex, orbitofrontal cortex, cingulate cortex, hippocampus and striatum. There was also evidence of pituitary enlargement and an excess of white matter hyperintensity volume in unipolar depression. Factors which influenced the magnitude of the observed effect sizes were differences in methods, clinical variables, pharmacological interventions and sample age.

P11 expression and PET in bipolar disorders

BACKGROUND

Bipolar disorder (BD) is a common mental disorder, subdivided into BD-I and BD-II. Currently, few biomarkers differentiate BD-I from BD-II. However, it is suggested that peripheral blood mononuclear cell (PBMC) mRNA levels of p11 and positron emission tomography (PET) might be potential biomarkers for BD.

METHODS

Healthy controls (HCs), BD-I, and BD-II patients in remission (n = 20 in each group) underwent a resting PET study with the radiotracer [(18)F]-2-deoxy-2-fluoro-d-glucose ((18)F-FDG). PBMC p11 mRNA levels were determined by quantitative real-time PCR.

RESULTS

Comparing BD patients to HCs, normalized glucose metabolism (NGM) was higher in the hippocampus, parahippocampus, and amygdala, but lower in the anterior cingulate cortex (aCC), medial prefrontal cortex (mPFC), dorsolateral prefrontal cortex (dlPFC), insula and thalamus. Compared to BD-II, BD-I had hypometabolism of glucose in the aCC, bilateral middle and inferior gyrus, insula and striatum, and hypermetabolism of glucose in the left parahippocampus. PBMC p11 mRNA was over-expressed in both BD-I and BD-II, although there was no significant difference in its expression levels between BD-I and B-II patients. Further, there were significant positive correlations between PBMC p11 mRNA and NGM in the mPFC, aCC, left insula, bilateral orbitofrontal cortex (OFC), and left middle, inferior and superior temporal gyri. Also, PBMC p11 mRNA was positively correlated to the number of depressive episodes in BD patients, especially in BD-I patients.

DISCUSSION

This study demonstrates that PBMC p11 mRNA expression is associated with neural activation in the brain of BD patients and warrants a larger translational study to determine its clinical utility.

Structural neuroimaging studies in major depressive disorder. Meta-analysis and comparison with bipolar disorder

CONTEXT

Although differences in clinical characteristics exist between major depressive disorder (MDD) and bipolar disorder (BD), consistent structural brain abnormalities that distinguish the disorders have not been identified.

OBJECTIVES

To investigate structural brain changes in MDD using meta-analysis of primary studies; assess the effects of medication, demographic, and clinical variables; and compare the findings with those of a meta-analysis of studies on BD.

DATA SOURCES

The MEDLINE, EMBASE, and PsycINFO databases were searched for studies from January 1, 1980, to February 2, 2010.

STUDY SELECTION

Two hundred twenty-five studies that used magnetic resonance imaging or x-ray computed tomography to compare brain structure in patients with MDD with that of controls were included in an online database, and 143 that measured common brain structures were selected for meta-analysis.

DATA EXTRACTION

Twenty-five variables, including demographic and clinical data, were extracted from each study, when available. For the meta-analysis, mean structure size and standard deviation were extracted for continuous variables, and the proportion of patients and controls with an abnormality in brain structure was extracted for categorical variables.

DATA SYNTHESIS

Compared with the structure of a healthy brain, MDD was associated with lateral ventricle enlargement; larger cerebrospinal fluid volume; and smaller volumes of the basal ganglia, thalamus, hippocampus, frontal lobe, orbitofrontal cortex, and gyrus rectus. Patients during depressive episodes had significantly smaller hippocampal volume than patients during remission. Compared with BD patients, those with MDD had reduced rates of deep white matter hyperintensities, increased corpus callosum cross-sectional area, and smaller hippocampus and basal ganglia. Both disorders were associated with increased lateral ventricle volume and increased rates of subcortical gray matter hyperintensities compared with healthy controls.

CONCLUSIONS

The meta-analyses revealed structural brain abnormalities in MDD that are distinct from those observed in BD. These findings may aid investigators attempting to discriminate mood disorders using structural magnetic resonance imaging data.

Pituitary volume prospectively predicts internalizing symptoms in adolescence

BACKGROUND

Early adolescence is a critical time for the development of both internalizing and externalizing disorders. We aimed to investigate whether pituitary volume, an index of hypothalamic-pituitary-adrenal (HPA) axis function, represents a vulnerability factor for the emergence of internalizing and externalizing symptoms during adolescence using a prospective, longitudinal design.

METHODS

One hundred and fifty-five adolescents completed 3T structural magnetic resonance imaging (MRI), symptom rating scales and a diagnostic interview during early adolescence (M age 12.6 years, SD .5 years); symptom rating scales were re-administered approximately three years later (M age 15.2 years). The volume of the pituitary gland was estimated by manually delineating its structure on MR images. The degree to which pituitary volumes prospectively predicted change in internalizing and externalizing symptoms across the two time-points was assessed using hierarchal linear regression, after controlling for the influence of gender, age, pubertal stage and intracranial volume.

RESULTS

Larger pituitary volumes prospectively predicted an increase in internalizing, but not externalizing, symptoms from early adolescence to mid-adolescence.

CONCLUSIONS

This study provides the first evidence that increased pituitary volume might represent a specific vulnerability marker for the development of internalizing symptoms during early to mid-adolescence.

Comparison of three methods for the estimation of the pituitary gland volume using magnetic resonance imaging: a stereological study

Stereological techniques using point counting and planimetry have been used to estimate pituitary gland volume. However, many studies have estimated pituitary gland volume by the mathematical approach the elliptic formula. The objective of the current study was to determine pituitary gland volume using stereological methods and elliptic formula on magnetic resonance imaging (MRI). In this study, pituitary gland volumes were estimated in a total of 28 subjects (22 females, 6 males,) who were free of any pituitary or neurological symptoms and signs. The mean ± SD pituitary gland volumes for the point counting, planimetry and elliptic formulae groups were 582.14 ± 140.16 mm³, 610.08 ± 133.17 mm³, and 432.82 ± 147.38 mm³, respectively. The mean CE for the pituitary gland volume estimates derived from the point counting technique was 8.07%. No significant difference was found between point counting and planimetric methods for the pituitary gland volume (P > 0.05). In addition, there was a 26.14 and 29.71% underestimation of pituitary volume as measured by the elliptic formula compared to the point counting and planimetric techniques, respectively. From these results, it can be concluded that stereological techniques are unbiased, efficient and reliable methods and are ideally suitable for in vivo examination of MRI data for pituitary gland volume estimation. Hence, we suggest that estimating pituitary gland volume using MRI study and stereology may be clinically relevant for pituitary surgeons for the investigation of the structure and function of the pituitary gland.

Longitudinal volume changes of the pituitary gland in patients with schizotypal disorder and first-episode schizophrenia

An enlarged volume of the pituitary gland has been reported in the schizophrenia spectrum, possibly reflecting the hypothalamic-pituitary-adrenal (HPA) hyperactivity. However, it remains largely unknown whether the pituitary size longitudinally changes in the course of the spectrum disorders. In the present study, longitudinal magnetic resonance imaging (MRI) data were obtained from 18 patients with first-episode schizophrenia, 13 patients with schizotypal disorder, and 20 healthy controls. The pituitary volume was measured at baseline and follow-up (mean, 2.7 years) scans and was compared across groups. The pituitary volume was larger in the schizophrenia patients than controls at baseline, and both patient groups had significantly larger pituitary volume than controls at follow-up. In a longitudinal comparison, both schizophrenia (3.6%/year) and schizotypal (2.7%/year) patients showed significant pituitary enlargement compared with controls (-1.8%/year). In the schizophrenia patients, greater pituitary enlargement over time was associated with less improvement of delusions and higher scores for thought disorders at the follow-up. These findings suggest that the pituitary gland exhibits ongoing volume changes during the early course of the schizophrenia spectrum as a possible marker of state-related impairments.

Pituitary volume in patients with panic disorder

Panic patients have many functional deficiencies in the hypothalamic-pituitary-adrenal (HPA) axis. Previous studies have shown changed pituitary gland volume in some psychiatric disorders that have functional deficiencies in the HPA axis. However, to date no study has evaluated the pituitary gland volume in patients with panic disorder (PD). We investigated the pituitary gland volume in patients with PD (n=27) and age- and sex-matched healthy controls (n=27), using 1.5-T magnetic resonance imaging in this study. Analysis showed that patients with PD had significantly smaller pituitary volume compared to healthy subjects. Patients with agoraphobia especially had a significantly smaller pituitary volume than patients without agoraphobia. There was a significant relationship between the pituitary volume and both the severity of symptoms and the illness duration in the patient group. The results show that patients with PD have reduced pituitary volume, which may reflect the functional abnormalities seen in this disorder. These findings may help us better understand the pathology of PD.

Volume of the adrenal and pituitary glands in depression

Numerous studies have shown that the hypothalamic-pituitary-adrenal (HPA) axis is hyperactive in some depressed patients. It is unclear whether such hyperactivity results in changed volumes of the adrenal glands, pituitary gland and hypothalamus. We systematically reviewed all controlled studies on the adrenal or pituitary glands or hypothalamus volume in unipolar depressive disorder published in PubMed 1966 to December 2009. We identified three studies that investigated the volume of the adrenal glands and eight studies that examined the volume of the pituitary gland, but no studies on hypothalamus were found. Two out of three studies found a statistically significant increase in adrenal volume in patients compared to controls. Four out of eight studies found a statistically significant increase in pituitary volume in patients compared to controls. Different methodological problems were identified such as small population samples, different subtypes of depression and insufficient matching of patients and controls. Due to large heterogeneity of study designs and data, it was futile to make a meta-analysis. It is concluded that it remains unclear whether hyperactivity of the HPA axis results in enlarged adrenal and pituitary glands and it is suggested that prospective studies should be conducted with scanning during successive depressive episodes and periods of remission.

Pituitary volume increase during emerging psychosis

BACKGROUND

Morphologic abnormalities of the pituitary gland volume (PV) have been reported in schizophrenia, but at what point in time they occur remains unclear. This study determines PV across different stages of emerging psychotic disorders compared to healthy controls.

METHODS

We compared PV of 36 individuals with an at-risk mental state (ARMS) for psychosis, 23 patients with a first episode psychosis (FEP) and 20 healthy controls (HC). Transition to psychosis was monitored using the BPRS transition criteria according to Yung et al. (Yung, A.R. et al., 1998. Prediction of psychosis. A step towards indicated prevention of schizophrenia. Br. J. Psychiatry Suppl. 172 (33), 14-20). Applying these transition criteria, 16 of the 36 ARMS individuals made the transition to psychosis (ARMS-T) and 20 did not (ARMS-NT). We traced PV manually on 1mm slices of magnetic resonance images in three dimensions (coronal, sagittal and axial) blind to group status. We used univariate analysis of covariance (ANCOVA) with PV as dependent variable, group and sex as between-subject factors and whole brain volume as covariate.

RESULTS

PV increased from HC to ARMS-NT to ARMS-T/FEP. ANCOVA revealed a significant effect of group (F(3,78)=3.0; p=.036) and a sex × group interaction (F(3,78)=6.5; p=.001). Over all groups, women had considerably larger PV than men (F(1,78)=9.8; p=.003).

CONCLUSIONS

Our findings provide further evidence that PV is increased in emerging psychotic disorders, and suggest that this is due to a stress-associated activation of the pituitary gland.

The hypothalamic-pituitary-adrenal axis and serotonin abnormalities: a selective overview for the implications of suicide prevention

Suicidal behavior and mood disorders are one of the world's largest public health problems. The biological vulnerability for these problems includes genetic factors involved in the regulation of the serotonergic system and stress system. The hypothalamic-pituitary-adrenal (HPA) axis is a neuroendocrine system that regulates the body's response to stress and has complex interactions with brain serotonergic, noradrenergic and dopaminergic systems. Corticotropin-releasing hormone and vasopressin act synergistically to stimulate the secretion of ACTH that stimulates the biosynthesis of corticosteroids such as cortisol from cholesterol. Cortisol is a major stress hormone and has effects on many tissues, including on mineralocorticoid receptors and glucocorticoid receptors in the brain. Glucocorticoids produce behavioral changes, and one important target of glucocorticoids is the hypothalamus, which is a major controlling center of the HPA axis. Stress plays a major role in the various pathophysiological processes associated with mood disorders and suicidal behavior. Serotonergic dysfunction is a well-established substrate for mood disorders and suicidal behavior. Corticosteroids may play an important role in the relationship between stress, mood changes and perhaps suicidal behavior by interacting with 5-HT1A receptors. Abnormalities in the HPA axis in response to increased levels of stress are found to be associated with a dysregulation in the serotonergic system, both in subjects with mood disorders and those who engage in suicidal behavior. HPA over-activity may be a good predictor of mood disorders and perhaps suicidal behavior via abnormalities in the serotonergic system.