Multihormonal responses to clonidine in patients with affective and psychotic symptoms

Molecular evidence of altered stress responsivity related to neuroinflammation in the schizophrenia midbrain

Stress and inflammation are risk factors for schizophrenia. Chronic psychosocial stress is associated with subcortical hyperdopaminergia, a core feature of schizophrenia. Hyperdopaminergia arises from midbrain neurons, leading us to hypothesise that changes in stress response pathways may occur in this region. To identify whether transcriptional changes in glucocorticoid and mineralocorticoid receptors (NR3C1/GR, NR3C2/MR) or other stress signalling molecules (FKBP4, FKBP5) exist in schizophrenia midbrain, we measured gene expression in the human brain (N = 56) using qRT-PCR. We assessed whether alterations in these mRNAs were related to previously identified high/low inflammatory status. We investigated relationships between stress-related transcripts themselves, and between FKBP5 mRNA, dopaminergic, and glial cell transcripts in diagnostic and inflammatory subgroups. Though unchanged by diagnosis, GR mRNA levels were reduced in high inflammatory compared to low inflammatory schizophrenia cases (p = 0.026). We found no effect of diagnosis or inflammation on MR mRNA. FKBP4 mRNA was decreased and FKBP5 mRNA was increased in schizophrenia (p < 0.05). FKBP5 changes occurred in high inflammatory (p < 0.001), whereas FKBP4 changes occurred in low inflammatory schizophrenia cases (p < 0.05). The decrease in mRNA encoding the main stress receptor (GR), as well as increased transcript levels of the stress-responsive negative regulator (FKBP5), may combine to blunt the midbrain response to stress in schizophrenia when neuroinflammation is present. Negative correlations between FKBP5 mRNA and dopaminergic transcripts in the low inflammatory subgroup suggest higher levels of FKBP5 mRNA may also attenuate dopaminergic neurotransmission in schizophrenia even when inflammation is absent. We report alterations in GR-mediated stress signalling in the midbrain in schizophrenia.

Association of growth hormone deficiency (GHD) with anxiety and depression: experimental data and evidence from GHD children and adolescents

Anxiety and depression are among the commonest emotional problems in children and young adolescents. They are encountered with even higher prevalence in children and adults with growth hormone deficiency (GHD). Alterations in the somatotropic axis, as observed in both GH/IGF1 deficiency and excess, can produce permanent changes in brain tissue structure. The growth hormone/insulin-like growth factor 1 (GH/IGF1) axis seems to exert a regulatory effect on brain function and neurogenesis, especially in the hippocampus, a brain region associated with mental and emotional disorders, such as depression and anxiety. There is evidence from animal models of the possible interrelationship of the endocrine system with the pathogenesis of emotional disorders. Moreover, clinical data support the association of GHD and mood disorders, which are often reversed by GH replacement therapy. However, the causal relationship and the mechanism underlying this association are to date obscure and remain to be clarified. The present review reports experimental data from animal models regarding the role of GH/IGF1 in emotional disorders and focuses on clinical data on the presence of these disorders in children with GHD and their response to GH therapy.

Dopaminergic, Noradrenergic, Adrenal, and Thyroid Abnormalities in Psychotic and Affective Disorders

BACKGROUND

This study aimed to assess hypothalamic-pituitary dopaminergic (DA), noradrenergic (NA), thyroid (HPT), and adrenal (HPA) activity in schizophrenia, in schizoaffective disorder, and in bipolar disorder.

METHOD

We investigated a combined approach of hormone responses to (1) apomorphine (APO), a short-acting DA receptor agonist which decreases prolactin secretion (PRL), and stimulates secretion of growth hormone (GH), adrenocorticotropin (ACTH), and cortisol; (2) clonidine (CLO), an alpha 2-adrenoceptor agonist which stimulates GH secretion; (3) 8 AM and 11 PM protirelin (TRH) which stimulates thyrotropin (TSH) secretion; and (4) dexamethasone which suppresses cortisol secretion, in 13 hospitalized healthy male controls and 39 untreated male inpatients: 13 with DSM-IV paranoid schizophrenia, 13 with DSM-IV schizoaffective disorder (bipolar subtype, depressed at the time of the study), and 13 with DSM-IV bipolar disorder (depressed).

RESULTS

Compared to controls, paranoid schizophrenic patients showed (1) lower APO-induced ACTH and cortisol stimulation, and (2) higher post-dexamethasone cortisol values. Compared to controls, schizoaffective and bipolar patients showed (1) lower ΔΔTSH values (i.e., difference between 11 PM and 8 AM TRH-TSH responses), (2) lower APO-induced PRL suppression, (3) lower CLO-induced GH stimulation, and (4) higher post-dexamethasone cortisol values.

CONCLUSIONS

Although results must be interpreted with caution because of the small sample, this preliminary study suggests that depressed bipolar and schizoaffective patients share common biological dysregulations, distinct from that of paranoid schizophrenic patients. From a pathophysiological viewpoint, paranoid schizophrenic patients can be characterized by hyposensitivity of the hypothalamic DA receptors (possibly resulting from an increase in presynaptic DA release) associated with increased HPA axis activity, while depressed bipolar and schizoaffective patients can be characterized by hyposensitivity of the pituitary TRH and DA-D₂ receptors (possibly linked to the activation of the hypothalamic TRH and tuberoinfundibular DA neurons, respectively), together with subsensitive postsynaptic α₂-adrenoreceptors at the hypothalamic level (possibly secondary to an erratic release of NA) and increased HPA axis activity.

Transcriptional changes in the stress pathway are related to symptoms in schizophrenia and to mood in schizoaffective disorder

Altered levels of stress-signalling transcripts have been identified in post-mortem brains of people with schizophrenia, and since stress effects may be expressed throughout the body, there should be similar changes in peripheral cells. However, the extent to which these markers are altered in peripheral white blood cells of people with schizophrenia is not known. Furthermore, how peripheral cortisol and stress-related mRNA are associated with negative symptom severity and emotional states in people with schizophrenia versus schizoaffective disorder has not been determined. Whole blood samples were collected from 86 patients with either schizophrenia or schizoaffective disorder (56 people with schizophrenia and 30 people with schizoaffective disorder), and 77 healthy controls. Total RNA was isolated, cDNA was synthesized, and stress-signalling mRNA levels (for NR3C1, FKBP5, FKBP4, PTGES3 and BAG1) were determined. Stress and symptom severity scores were measured by the Depression, Anxiety and Stress Scale, and the Positive and Negative Syndrome Scale, respectively. We found increased FKBP5 mRNA, Z(156) = 2.5, p = 0.01, decreased FKBP4 mRNA, t(155) = 3.5, p ≤ 0.001, and decreased PTGES3 mRNA, t(153) = 3.0, p ≤ 0.01, in schizophrenia and schizoaffective disorder cohorts combined compared to healthy controls. Stress-related peripheral mRNA levels were differentially correlated with negative emotional states and symptom severity in schizoaffective disorder (β's = -0.45-0.56, p's = 0.05-0.001) and schizophrenia (β's = -0.34-0.38, p's = 0.04-0.03), respectively. Therefore, molecules of the stress-signalling pathway appear to differentially contribute to clinical features of schizophrenia versus schizoaffective disorder.

Characteristics and heterogeneity of schizoaffective disorder compared with unipolar depression and schizophrenia - a systematic literature review and meta-analysis

BACKGROUND

Comparisons of illness characteristics between patients with schizoaffective disorder (SAD) patients and unipolar depression (UD) are rare, even though UD is one of the most important differential diagnoses of SAD. Also, the variability of illness characteristics (heterogeneity) has not been compared. We compared illness characteristics and their heterogeneity among SAD, UD, and - as another important differential diagnosis - schizophrenia (S).

METHODS

In order to reduce sampling bias we systematically searched for studies simultaneously comparing samples of patients with SAD, UD, and S. Using random effects and Mantel-Haenszel models we estimated and compared demographic, illness course and psychopathology parameters, using pooled standard deviations as a measurement of heterogeneity.

RESULTS

Out of 155 articles found by an earlier meta-analysis, 765 screened in Medline, 2738 screened in EMBASE, and 855 screened in PsycINFO we selected 24 studies, covering 3714 patients diagnosed according to RDC, DSM-III, DSM-IIIR, DSM-IV, or ICD-10. In almost all key characteristics, samples with schizoaffective disorders fell between unipolar depression and schizophrenia, with a tendency towards schizophrenia. On average, UD patients were significantly older at illness onset (33.0 years, SAD: 25.2, S: 23.4), more often women (59% vs. 57% vs. 39%) and more often married (53% vs. 39% vs. 27%). Their psychopathology was also less severe, as measured by BPRS, GAS, and HAMD. In demographic and clinical variables heterogeneity was roughly 5% larger in UD than in SAD, and samples of patients with schizophrenia had the lowest pooled heterogeneity. A similar picture emerged in a sensitivity analysis with coefficient of variation as the measurement of heterogeneity.

LIMITATIONS

Relative to bipolar disorder there are fewer studies including unipolar patients. No studies based on DSM-5 could be included.

CONCLUSIONS

Regarding unipolar affective disorder this study confirms what we have shown for bipolar disorders in earlier studies: schizoaffective disorder falls between schizophrenia and affective disorders, and there are relevant quantitative differences in key illness characteristics, which supports the validity of the schizoaffective disorder concept. Contrary to our expectations heterogeneity is not larger in SAD than in UD and not substantially higher than in S. Lower reliability of the diagnosis of SAD therefore cannot be ascribed to higher variability of illness characteristics in SAD.

Morning cortisol levels in schizophrenia and bipolar disorder: a meta-analysis

Increased peripheral levels of morning cortisol have been reported in people with schizophrenia (SZ) and bipolar disorder (BD), but findings are inconsistent and few studies have conducted direct comparisons of these disorders. We undertook a meta-analysis of studies examining single measures of morning cortisol (before 10 a.m.) levels in SZ or BD, compared to controls, and to each other; we also sought to examine likely moderators of any observed effects by clinical and demographic variables. Included studies were obtained via systematic searches conducted using Medline, BIOSIS Previews and Embase databases, as well as hand searching. The decision to include or exclude studies, data extraction and quality assessment was completed in duplicate by LG, SM and AS. The initial search revealed 1459 records. Subsequently, 914 were excluded on reading the abstract because they did not meet one or more of the inclusion criteria; of the remaining 545 studies screened in full, included studies were 44 comparing SZ with controls, 19 comparing BD with controls, and 7 studies directly comparing schizophrenia with bipolar disorder. Meta-analysis of SZ (N=2613, g=0.387, p=0.001) and BD (N=704, g=0.269, p=0.004) revealed moderate quality evidence of increased morning cortisol levels in each group compared to controls, but no difference between the two disorders (N=392, g=0.038, p=0.738). Subgroup analyses revealed greater effect sizes for schizophrenia samples with an established diagnosis (as opposed to 'first-episode'), those that were free of medication, and those sampled in an inpatient setting (perhaps reflecting an acute illness phase). In BD, greater morning cortisol levels were found in outpatient and non-manic participants (as opposed to those in a manic state), relative to controls. Neither age nor sex affected cortisol levels in any group. However, earlier greater increases in SZ morning cortisol were evident in samples taken before 8 a.m. (relative to those taken after 8 a.m.). Multiple meta-regression showed that medication status was significantly associated with morning cortisol levels in SZ, when the effects of assay method, sampling time and illness stage were held constant. Heightened levels of morning cortisol in SZ and BD suggest long-term pathology of the hypothalamic-pituitary-adrenal (HPA) axis that may reflect a shared process of illness development in line with current stress-vulnerability models.

Is elevated norepinephrine an etiological factor in some cases of schizophrenia?

A number of hypotheses have been put forth regarding the etiology of schizophrenia, including the dopamine hypothesis, NMDA receptor hypofunction hypothesis, and others. A lesser known theory is that elevated noradrenergic signaling plays a causative role in the disease. This paper briefly re-examines the merits of this hypothesis, including as it relates to some recently published studies. Several lines of evidence are investigated, including: endogenous level studies of norepinephrine (NE); modulation of the disease by noradrenergic drugs; association of the disease with bipolar disorder and hypertension, since these latter two conditions may involve elevated NE transmission; and effects of psychological stress on the disease, since stress can produce elevated release of NE. For many of these lines of evidence, their relationship with prepulse inhibition of startle is examined. A number of these studies support the hypothesis, and several suggest that elevated NE signaling plays a particularly prominent role in the paranoid subtype of schizophrenia. If the hypothesis is correct for some persons, conventional pharmaceutical treatment options, such as use of atypical antipsychotics (which may themselves modulate noradrenergic signaling), may be improved if selective NE transmission modulating agents are added to or even substituted for these conventional drugs.

Schizoaffective disorder diagnosed according to different diagnostic criteria--systematic literature search and meta-analysis of key clinical characteristics and heterogeneity

BACKGROUND

Schizoaffective disorder is viewed as a heterogeneous diagnosis among psychotic illnesses. Different diagnostic systems differ in their definition with DSM (-IIIR, -IV, and -V) providing a narrower definition than RDC and ICD-10. It is unclear whether this difference is reflected in patient samples diagnosed according to different diagnostic systems.

METHODS

Exploratory study based on a systematic review of studies of schizoaffective disorder samples diagnosed by either RDC and ICD-10 (group of "broad criteria") or DSM-IIIR and -IV ("narrow criteria"); comparison (by Mann-Whitney-U-tests) of key characteristics, such as age, number of hospitalizations, or scores in psychometric tests, between more broadly and more narrowly defined schizoaffective disorder samples using standard deviations as a measurement of heterogeneity as well as weighted means and percentages. To reduce selection bias only studies including schizoaffective patient samples together with affective disorder and schizophrenia samples were selected.

RESULTS

55 studies were included, 14 employing RDC, 4 ICD-10, 20 DSM-IIIR, and 17 DSM-IV. Thirteen characteristics were compared: patients diagnosed according to broader criteria had fewer previous hospitalizations (2.2 vs. 5.4) and were both less often male (42 vs. 51%) and married (21 vs. 40%). Heterogeneity was similar in both groups but slightly higher in RDC and ICD-10 samples than in DSM-IIIR and -IV-samples: +4% regarding demographic and clinical course data and +13% regarding psychometric tests (pooled SD).

LIMITATIONS

Secular trends and different designs may have confounded the results and limit generalizability. Some comparisons were underpowered.

CONCLUSIONS

Differences in diagnostic criteria are reflected in key characteristics of samples. The association of larger heterogeneity with wider diagnostic criteria supports employing standard deviations as a measurement of heterogeneity.

Prolactin and psychopathology in schizophrenia: a literature review and reappraisal

Secretion of the anterior pituitary hormone prolactin can be significantly increased by antipsychotic drugs, leading to a range of adverse effects in patients with schizophrenia. However, there is evidence from a variety of studies that prolactin may also be related to symptom profile and treatment response in these patients, and recent work has identified variations in prolactin secretion even in drug-free patients. In this paper, a selective review of all relevant studies pertaining to prolactin and schizophrenia, including challenge and provocation studies, is presented. The implications of this work are discussed critically. A tentative model, which synthesizes these findings and argues for a significant role for prolactin in the development of schizophrenia, is outlined.

Growth hormone, prolactin and cortisol response to exercise in patients with depression

BACKGROUND

A blunted growth hormone and prolactin response to pharmacological stress test have previously been found in depressed patients, as well as an increased cortisol response to psychosocial stress. This study investigated these hormones in response to acute exercise using an incremental bicycle test.

METHOD

A cross-sectional comparison of cortisol, growth hormone, and prolactin in depressed (n=137) and healthy (n=44) subjects during rest and in response to an incremental bicycle test. Secondly, we tested the depressed patients again after a 4-month randomized naturalistic exercise intervention.

RESULTS

Resting plasma levels of growth hormone (GH), cortisol, or prolactin (PRL) did not differ between depressed and healthy subjects (all p-values>.12). In response to an incremental bicycle test the GH (p=.02) and cortisol (p=.05) response in depressed was different compared to healthy controls. The effect of acute exercise stress on PRL (p=.56) did not differ between depressed and healthy subjects. Apart from a decrease in GH response in the strength-training group (p=.03) the pragmatic exercise intervention did not affect resting hormonal levels, or the response to acute exercise.

CONCLUSIONS

Patients with mild to moderate depression had a different growth hormone and cortisol response to acute exercise stress compared to healthy controls. Strength training was able to reduce the growth hormone response to acute exercise stress in this patient population. Studies with more rigorous inclusion criteria and higher exercise frequencies are needed to evaluate and confirm the possible effect of exercise in depressed subjects.

Is schizoaffective disorder a distinct categorical diagnosis? A critical review of the literature

Considerable debate surrounds the inclusion of schizoaffective disorder in psychiatric nosology. Schizoaffective disorder may be a variant of schizophrenia in which mood symptoms are unusually prominent but not unusual in type. This condition may instead reflect a severe form of either major depressive or bipolar disorder in which episode-related psychotic symptoms fail to remit completely between mood episodes. Alternatively, schizoaffective disorder may reflect the co-occurrence of two relatively common psychiatric illnesses, schizophrenia and a mood disorder (major depressive or bipolar disorder). Each of these formulations of schizoaffective disorder presents nosological challenges because the signs and symptoms of this condition cross conventional categorical diagnostic boundaries between psychotic disorders and mood disorders. The study, evaluation, and treatment of persons presently diagnosed with schizoaffective may be more usefully informed by a dimensional approach. It is in this context that this article reviews and contrasts the categorical and dimensional approaches to its description, neurobiology, and treatment. Based on this review, an argument for the study and treatment of this condition using a dimensional approach is offered.

Platelet imidazoline receptors as state marker of depressive symptomatology

OBJECTIVE

Previous studies have shown that imidazoline receptors (IR-1) are increased in platelets and frontal cortex of depressed patients, and this up-regulation is normalized (down-regulated) after antidepressant drug treatments. It has been hypothesized that IR-1 up-regulation during the depressive episode may be a state marker for depressive symptomatology. The goal of the present study was to address the state versus trait question.

METHOD

Twelve healthy subjects (six males and six females) met stringent inclusion and exclusion criteria for physical and mental health. They received desipramine for 6 weeks in order to simulate the length of time and dosing used previously to obtain an IR-1 down-regulation and a therapeutic response in depressed patients. Outcome and safety measures included clinical, psychological, and cardiovascular assessments obtained throughout the study. Plasma concentrations of desipramine were measured throughout the 6 weeks of treatment and again after 2 weeks following tapered discontinuation of desipramine. Platelet receptors were assessed by Western blotting and radioligand binding assays.

RESULTS

Healthy subjects taking desipramine experienced mild dysphoric effects but there were no adverse events. The binding of 8 nM p-[(125)I]clonidine to IR-1 and alpha(2)-adrenoceptors in healthy subjects did not change during desipramine treatment. The immunodensity of the 33 kDa band associated with IR-1 gradually increased to a maximum, by week-6, of 26% higher than baseline (p < 0.01 compared to baseline). Two weeks after desipramine discontinuation, there was a decline in alpha(2)-adrenoceptor binding and 33 kDa band's immunodensity (p = 0.04).

CONCLUSIONS

The findings support the hypothesis that platelet IR-1 binding sites are a marker of mood state rather than of antidepressant-induced pharmacological regulation. By comparison, platelet alpha(2)-adrenoceptors appear to be regulated by desipramine as a pharmacological effect independent of mood state.

Persistent alterations in biological profiles in women with abuse histories: influence of premenstrual dysphoric disorder

OBJECTIVE

To examine dysregulation in biological measures associated with histories of abuse in women and whether women with premenstrual dysphoric disorder (PMDD) differ in their dysregulation.

DESIGN

Twenty-five women meeting prospective criteria for PMDD and 42 non-PMDD controls underwent structured interview to determine abuse histories and lifetime Axis I diagnoses, excluding those with current Axis I disorders or using medications.

MAJOR OUTCOME MEASURES

Plasma cortisol and norepinephrine (NE), heart rate (HR), blood pressure (BP), and vascular resistance index (VRI) were assessed at rest and in response to mental stress.

RESULTS

A greater proportion of PMDD women had prior abuse compared with non-PMDD women. Regardless of PMDD status, all abused women had lower plasma NE and higher HRs and tended to have lower plasma cortisol at rest and during stress. Abused women also reported more severe daily emotional and physical symptoms. Greater VRI and BP at rest and during stress were seen only in PMDD women with abuse.

CONCLUSION

There is persistent dysregulation in stress-responsive systems in all abused women that cannot be accounted for by current psychiatric illness or medications, and PMDD women may be differentially more vulnerable to the impact of abuse on measures reflecting alpha-adrenergic receptor function.

Cortisol hypersecretion in unipolar major depression with melancholic and psychotic features: dopaminergic, noradrenergic and thyroid correlates

Evidence supports that hyperactivity of the hypothalamic-pituitary-adrenal axis has a pivotal role in the psychobiology of severe depression. The present study aimed at assessing hypothalamic-pituitary dopaminergic, noradrenergic, and thyroid activity in unipolar depressed patients with melancholic and psychotic features and with concomitant hypercortisolemia. Hormonal responses to dexamethasone, apomorphine (a dopamine receptor agonist), clonidine (an alpha 2-adrenoreceptor agonist) and 0800 and 2300 h protirelin (TRH) were measured in 18 drug-free inpatients with a DSM-IV diagnosis of severe major depressive disorder with melancholic and psychotic features showing cortisol nonsuppression following dexamethasone and 23 matched hospitalized healthy controls. Compared with controls, patients showed (1) lower adrenocorticotropin and cortisol response to apomorphine (p<0.015 and <0.004, respectively), (2) lower growth hormone response to clonidine (p=0.001), and (3) lower responses to TRH: 2300 h maximum increment in serum thyrotropin (TSH) level (p=0.006) and the difference between 2300 and 0800 h maximum increment in serum TSH values (p=0.0001). Our findings, in a subgroup of unipolar depressed inpatients with psychotic and melancholic features, are compatible with the hypothesis that chronic elevation of cortisol may lead to dopaminergic, noradrenergic and thyroid dysfunction.

The effect of long-term antipsychotic treatment on prolactin

OBJECTIVE

This naturalistic, cross-sectional study was designed to assess the risk of prolactin level elevation and associated side effects in youths taking long-term atypical antipsychotic medication.

METHOD

Subjects were enrolled from outpatient child psychiatric treatment settings in upstate New York who were taking risperidone, olanzapine, or quetiapine for at least 6 months. Demographic data, medication history, and side effects were elicited at the initial interview. Two fasting morning serum prolactin levels were obtained 1 month apart, and the results were averaged.

RESULTS

Fifty outpatient youths, with a median age of 13 years, were enrolled in the study. The median overall duration of use of an atypical antipsychotic was 22.1 months. The median dose of medication for risperidone was 1.5 mg/day, for olanzapine 10 mg/day, and for quetiapine 200 mg/day. The mean prolactin level among all patients on risperidone was significantly greater than controls, as well as for those on quetiapine or olanzapine.

CONCLUSIONS

The risk of hyperprolactinemia with long-term use of risperidone appears to be significantly greater than for olanzapine or quetiapine. Overt side effects were infrequent in the overall sample, but serum prolactin assessment is recommended for youths taking risperidone chronically. Because of variability found in sequential prolactin samples, repeat samples may be warranted.

Histories of sexual abuse are associated with differential effects of clonidine on autonomic function in women with premenstrual dysphoric disorder

In women meeting strict criteria for premenstrual dysphoric disorder (PMDD), we examined whether clonidine, an alpha2-adrenergic receptor (AR) agonist, would have different effects on sexually abused versus non-abused PMDD women for measures of autonomic nervous system function. Twelve women meeting prospective, DSM-IV criteria for PMDD, five of whom had a history of sexual abuse, participated in a randomized, placebo-controlled, double-blind, cross-over design study, comparing 2 months of on oral clonidine (0.3 mg/day) with 2 months on active placebo. During the luteal phase that preceded randomization and following each two-month challenge, women were tested for cardiovascular measures at rest and in response to mental stress, and for resting plasma norepinephrine (NE) concentrations as well as beta1 and beta2-AR responsivity using the isoproterenol sensitivity test. Results revealed that in comparison to placebo, clonidine significantly reduced plasma norepinephrine concentrations, increased both beta1- and beta2-AR responsivity, and reduced resting and stress heart rate (HR) and blood pressure (BP) (p < 0.05) in all PMDD women. With clonidine, sexually abused PMDD women exhibited greater decreases in resting and stress-induced HR (p < 0.01) and stress-induced systolic BP (p < 0.05), while non-abused PMDD women exhibited greater reductions in plasma NE concentration (p = 0.07), and greater increases in beta2-AR responsivity (p < 0.05) than abused PMDD women. These results suggest PMDD women with and without a history of sexual abuse respond differently to a clonidine challenge in measures reflecting autonomic nervous system functioning, indicating that abuse may modify presynaptic alpha2-AR function in PMDD.

AVP- and OT-neurophysins response to apomorphine and clonidine in major depression

A number of studies have reported abnormalities of neurohypophyseal secretions in major depressive disorder. The purpose of the present study was to test the influence of apomorphine and clonidine injections on plasma vasopressin (AVP)-neurophysins and oxytocin(OT)-neurophysins levels, as direct index of posterior pituitary activation in major depression. Apomorphine and clonidine tests were carried out in 25 medication-free depressive patients and 25 age and gender-matched healthy controls. Blood for neurophysins analysis was drawn by venipuncture at t0, t + 20, t + 40, t + 60 and t + 120. Baseline AVP-neurophysins concentrations were significantly lower in depressives (0.12 +/- 0.14 ng/ml) than in healthy subjects (0.24 +/- 2.15 ng/ml) (p < 0.04). The response to apomorphine test revealed a significant reduced response at 20 (p = 0.01), 40 (p = 0.007) and 60 (p = 0.02) and 120 (p = 0.02)min. Following clonidine test, post hoc tests also revealed a significant decrease at 0 (p = 0.04), 20 (p = 0.01), 40 (p = 0.007) and 60 (p = 0.02) and 120 (p = 0.006)min. Concerning OT-neurophysins, no significant differences were found between depressed and controls in response to clonidine or apomorphine injections. Following clonidine and apomorphine, major depressives exhibited a significantly lower peak GH response than controls. The study supports partially the hypothesis of a reduced vasopressinergic activity in depression. Moreover, we did not find any influence of acute apomorphine or clonidine injections on vasopressin-neurophysin or oxytocin-neurophysin in depressive patients.

Basal prolactin values correlate with response to reboxetine treatment in major depression, but not with response to citalopram

Little is known about variables that might predict outcome in major depression. Recently, basal prolactin values (BPV) have been suggested to predict response to treatment with tricyclic antidepressive drugs. In order to examine whether BPV predict response to selective mono-aminergic therapy, 24 in-patients with major depression were treated in a single-masked, randomised study using the most selective noradrenergic or serotonergic reuptake inhibitors available for antidepressant treatment, i.e. reboxetine and citalopram. A significant correlation between BPV and treatment response to reboxetine was found, but not between BPV and response to citalopram. As BPV are influenced by noradrenergic activity, it can be hypothesized that depressed patients with comparatively high BPV have a relatively high noradrenergic function. This might explain why in our study depressed patients with the highest BPV responded strongest to selective noradrenergic treatment with reboxetine. As measurement of BPV is simple, further studies are suggested to examine the possible clinical value of the link between prolactin, noradrenergic function in major depression and treatment response.

Endocrine disturbances in depression

Depression is one of the most common psychiatric disorders. For a long time, clinicians suspected a causal link between depression and the endocrine system. The most frequently occurring endocrine abnormality in depressed subjects is hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis. CRH and AVP are likely to play a substantial role in the pathophysiology of this disorder, and their receptors appear to be a specific target for future antidepressant drugs. Depression also affects the hypothalamic-pituitary-GH (HPGH) and -thyroid (HPT) axes. Alterations in the reproductive system may also play a role in the pathology of depression. In addition, there is increasing evidence that leptin and neurosteroids, such as DHEA, are implicated in mood disorders.

Growth hormone, cortisol and prolactin responses to physical exercise: higher prolactin response in depressed patients

This study was designed to compare growth hormone, cortisol and prolactin responses to physical exercise in depressed patients and healthy comparison subjects. Patients fulfilled the DSM-IV diagnostic criteria for current major depressive disorder; subjective depressive symptoms were rated with Montgomery-Asberg Depression Rating Scale (MADRS) immediately before the experiment. Growth hormone, cortisol and prolactin were measured before and immediately after physiologically stressful bicycle cardiopulmonary exercise test. After exercise, there were three additional hormone measurements, with 30-min intervals. No significant difference was found in baseline growth hormone, cortisol or prolactin levels between patients and the control group. Plasma growth hormone and cortisol levels increased significantly during physical exercise in both patients and controls and returned to baseline in 90 min. There was no significant difference in growth hormone or cortisol responses to physical exercise between the two groups. However, prolactin levels increased only in the depressed patients group during the exercise. We hypothesize that acute exercise may have a stronger effect on serotonin (5-HT) release in depressed patients, which is reflected in increased plasma prolactin concentration.

Mirtazapine decreases stimulatory effects of reboxetine on cortisol, adrenocorticotropin and prolactin secretion in healthy male subjects

Reboxetine is a selective noradrenaline reuptake inhibitor, whereas mirtazapine acts as an antagonist at noradrenergic alpha(2), serotonin (5-HT(2)), 5-HT(3) and histamine H(1) receptors. In a former study we could demonstrate an inhibitory impact of mirtazapine on cortisol secretion. In the present investigation, the influence of combined administration of 15 mg mirtazapine and 4 mg reboxetine on the cortisol (COR), adrenocorticotropin (ACTH), growth hormone (GH), and prolactin (PRL) secretion was examined in 12 healthy male subjects, compared to reboxetine alone (4 mg). In a randomized order, the subjects received reboxetine (4 mg) alone or the combination of reboxetine (4 mg) and mirtazapine (15 mg) at 8:00 a.m. on two different days. After insertion of an intravenous catheter, blood samples were drawn 1 h prior to the administration of single reboxetine or the combination (reboxetine and mirtazapine), at time of administration, and during the time of 5 h thereafter in periods of 30 min. Serum concentrations of COR, GH, and PRL as well as plasma levels of ACTH were determined in each blood sample by means of double antibody RIA, fluoroimmunoassay and chemiluminescence immunometric assay methods. The area under the curve (AUC) was used as parameter for the COR, ACTH, GH, and PRL response. For statistical evaluation, the Wilcoxon signed-ranks test was performed. There was a pronounced stimulation of COR, ACTH, GH, and PRL concentrations after single administration of reboxetine. When reboxetine was given in combination with mirtazapine, a significant reduction of the COR, ACTH, and PRL stimulation was observed whereas GH secretion patterns remained unchanged, compared to single administration of reboxetine. Apparently, the stimulatory effects of reboxetine on pituitary hormone secretion via noradrenergic mechanisms are counteracted in part by the alpha(2)-blocking properties of mirtazapine and its inhibitory influence on cortisol secretion.

The roots of depression in adolescent girls: is menarche the key?

Before adolescence, the rates of depression are similar in girls and boys (or are slightly higher in boys). Yet with the onset of puberty, the gender proportion of depression dramatically shifts to a two girls to one boy ratio. What, then, is the relationship between menarche and the onset of major depression in early adolescence? Recent literature intimates that vulnerability to depression may be rooted in an intricate meld of genetic traits, normal female hormonal maturational processes, and gender socialization. Information regarding gender differences in the presentation of depressive symptoms is provided along with biologic, psychologic, and sociologic factors contributing to depression in adolescent girls. The burden of illness associated with onset of depression after menarche reinforces the importance of prevention or else expeditious recognition and intervention.

Noradrenergic dysfunction and antidepressant treatment response

The purpose of this study was to investigate differences in outcome following treatment with two different antidepressants in depressed patients according to their pretreatment hormonal response to clonidine. In all, 62 drug-free DSM-IV recurrent major depressed patients and 20 normal controls were studied. Patients were subsequently treated for 4 weeks with fluoxetine (n=28), or amitriptyline (n=34), and were then classified as responders or nonresponders according to their final Hamilton depression scale score. Compared to controls, depressed patients showed lower GH response to CLO (DeltaGH) (P<0.0002). One control (5%) and 35 depressed patients (56%) had blunted DeltaGH values. The efficacy of the two antidepressants was not significantly different: 15 patients responded to AMI (44%), seven patients responded to FLUOX (25%) (P>0.15). However, in the subgroup of patients with blunted DeltaGH levels, the rate of responders was higher for AMI (11/21) compared to FLUOX (1/14) treated patients (P<0.01). These results suggest that in depressed patients a blunted GH response to CLO could predict antidepressant response.