Distraction versus focusing during VR exposure therapy for acrophobia: A randomized controlled trial

BACKGROUND AND OBJECTIVES

The therapeutic mechanisms of exposure therapy are not well understood. Research suggests that focusing on the most feared aspect might not be necessary, and that distraction with a low cognitive load (e.g., conversation) might enhance exposure. We aimed at systematically testing the efficacy of exposure therapy with focusing vs. conversational distraction, hypothesizing that distracted exposure would yield superior effects.

METHODS

Thirty-eight patients with acrophobia (specific phobia of heights; clinician-determined) (free from relevant somatic or other mental disorders) were randomly assigned (1:1) to one virtual reality (VR) session of either focused (n = 20) or distracted exposure (n = 18). This monocentric trial took place at a psychiatric university hospital.

RESULTS

Both conditions resulted in a significant reduction of acrophobic fear and avoidance, and a significant increase of self-efficacy (primary outcome variables). However, condition did not have a significant effect on any of these variables. Effects were stable at four-week follow-up. Heart rate and skin conductance level indicated significant arousal, but did not differ between conditions.

LIMITATIONS

Eye-tracking was unavailable, nor did we assess emotions other than fear. Power was limited due to sample size.

CONCLUSIONS

A balanced exposure protocol combining attention to fear cues with conversational distraction, while not being superior, might be as effective as focused exposure for acrophobia, at least during the initial stages of exposure therapy. These results support previous findings. This study demonstrates how VR can be exploited for therapy process research, as VR supports dismantling designs and the incorporation of online process measures.

Non-Hunner's Interstitial Cystitis Is Different from Hunner's Interstitial Cystitis and May Be Curable by Uterosacral Ligament Repair

Background

The posterior fornix syndrome (PFS) was first described in 1993 as a predictably occurring group of symptoms: chronic pelvic pain (CPP), urge, frequency, nocturia, emptying difficulties/urinary retention, caused by uterosacral ligament (USL) laxity, and cured by repair thereof.

Summary

Our hypothesis was that non-Hunner's interstitial cystitis (IC) and PFS are substantially equivalent conditions. The primary objective was to determine if there was a causal relationship between IC and pelvic organ prolapse (POP). The secondary objective was to assess whether other pelvic symptoms were present in patients with POP-related IC and if so, which ones? How often did they occur? A retrospective study was performed in 198 women who presented with CPP, uterine/apical prolapse (varying degrees), and PFS symptoms, all of whom had been treated by posterior USL sling repair. We compared their PFS symptoms with known definitions of IC, CPP, and bladder symptoms. To check our hypothesis for truth or falsity, we used a validated questionnaire, “simulated operations” (mechanically supporting USLs with a vaginal speculum test to test for reduction of urge and pain), transperineal ultrasound and urodynamics.

Key Messages

198 patients had CPP and 313 had urinary symptoms which conformed to the definition for non-Hunner's IC. The cure rate after USL sling repair was CPP 74%, urge incontinence 80%, frequency 79.6%, abnormal emptying 53%, nocturia 79%, obstructive defecation 80%. Our findings seem to support our hypothesis that non-Hunner's IC and PFS may be similar conditions; also, non-Hunner IC/BPS may be a separate or lesser disease entity from “Hunner lesion disease”. More rigorous scientific investigation, preferably by RCT, will be required.

Atrial natriuretic peptide (ANP) as an endogenous anxiolytic in patients with heart failure? - No replication of previous results showing an inverse association of anxiety and plasma ANP parameters

OBJECTIVE

An acute anxiolytic-like effect of atrial natriuretic peptide (ANP) has been demonstrated in several preclinical and clinical studies. In a so far singular study (Herrmann-Lingen et al., 2003), patients with congestive heart failure, who pathognomonicly display increased plasma ANP, showed a significant inverse association of anxiety symptoms and pro-ANP levels, giving rise to speculations about ANP as an endogenous anxiolytic. We tried to replicate and extend this preliminary finding.

METHODS

In 56 patients suffering from heart failure with reduced left ventricular ejection fraction we measured ANP, mid-regional pro-ANP (MR-proANP) and cyclic guanosine monophosphate (cGMP) as plasma parameters of ANP functioning and characterized anxiety symptoms using the Hospital Anxiety and Depression Scale (HADS) and in addition the State Trait Anxiety Inventory (STAI) for state anxiety. Spearman rank correlation coefficients were calculated.

RESULTS

None of our plasma ANP parameters showed a significant association with anxiety symptoms as per HADS ratings. The same picture emerged with STAI state anxiety. ANP, MR-proANP and cGMP significantly correlated with each other.

CONCLUSION

In another sample of patients with heart failure we were unable to replicate previous and preliminary cross-sectional findings of low anxiety in subjects with high plasma pro-ANP. Direct measurement of effector hormone ANP and its second messenger as well did not support our hypothesis. Chronically elevated ANP in heart failure might attenuate its potential anxiolytic effects. Longitudinal studies experimentally increasing ANP levels in anxious heart failure patients are needed to test if this approach has clinical psychotropic utility.

Symptoms of voiding dysfunction and other coexisting pelvic floor dysfunctions: the impact of transvaginal, mesh-augmented sacrospinous ligament fixation

INTRODUCTION AND HYPOTHESIS

The objective was to investigate the prevalence for voiding dysfunction and if symptom improvement can be achieved by adequate pelvic floor surgery.

METHODS

We evaluated the Propel Study data from 281 women with pelvic organ prolapse (POP) stage 2-4. Bother caused by obstructive micturition, voiding dysfunction, and coexisting pelvic floor symptoms were assessed using the Pelvic Floor Distress Inventory (PFDI) preoperatively and 6, 12, and 24 months after vaginal prolapse repair. Successful reconstruction (Pelvic Organ Prolapse Quantification [POP-Q] stage 0-I throughout the 2-year follow-up at all compartments, "responders"), was compared with all others ("non-responders").

RESULTS

Prevalence of voiding dysfunction was significantly reduced after surgery for all patients with "moderate" to "quite a bit" of bother ("R2") regarding all examined PFDI questions. Defects of the posterior/apical compartment and lower stage defects were found to cause obstructive micturition, which improved significantly after POP surgery. Six months after surgery, the prevalence of R2 for voiding dysfunction symptoms was reduced significantly for responders compared with non-responders. Significant reduction of R2 in patients with rectoceles could be shown for some PFDI questions, whereas the rate was lower in patients with cystoceles. Other pelvic floor symptoms often coexisted in patients with voiding dysfunction symptoms and improved significantly after surgery as well.

CONCLUSIONS

Symptoms of voiding dysfunction are frequent in female patients with POP and can significantly improve after vaginal mesh-augmented prolapse repair even for posterior and minor defects. Before counseling patients to undergo POP surgery because of their obstructive symptoms, other causes of voiding dysfunction must first have been ruled out.

A low cost artisan tension-free tape technique cures pelvic organ prolapse and stress urinary incontinence - proof of concept

INTRODUCTION

The primary cause of pelvic organ prolapse (POP) is weak cardinal/uterosacral (CL/USL) ligaments and for stress urinary incontinence, weak pubourethral ligaments (PUL).

MATERIAL AND METHODS

A 1 cm wide tape cut from a mesh sheet was applied tension-free to reinforce already plicated CL/USLs for cure of prolapse and directly to PUL for cure of stress urinary incontinence (SUI). 40 tapes were inserted, 10 midurethrally for SUI and 30 for 2nd/3rd degree prolapse: 15 to uterosacral ligaments and 15 to cardinal ligaments.

RESULTS

At 12 months follow-up there was 72% cure for POP, 70% for SUI and improvement in urge/nocturia symptoms in 82% of patients.At 36 months 8/15 patients were evaluated. Anatomic cure for POP III was 2/4, for POP I-II 6/6.

CONCLUSIONS

Though a 'proof of concept' study, our results may be sufficient to provide, in time, an alternative individual pathway for surgeons wishing to provide more certainty to a prolapse repair than 'native tissue' for an individual patient. The method questions whether expensive mesh kits are really necessary: our data though small, actually part of a learning curve, was within 15 percentage points of more sophisticated, more expensive tensioned slings. Intraoperative complications were low with no tape erosions seen at 12 months. Further validation with larger prospective and comparative trials is required.

The renin secretion profile under the influence of sleep deprivation and the neuropeptides CRH and GHRH

It is already known that during normal sleep plasma renin activity (PRA) shows oscillations with decreases during rapid-eye-movement (REM) sleep and increases during non-REM (NREM) sleep. We also know that renin correlates positively with slow-wave sleep (SWS). Sleep deprivation is known to enhance significantly SWS and slow wave activity (SWA, known as δ power). Based on these findings we addressed the question whether and to which extent sleep deprivation may affect the synchronization found between PRA and REM sleep during normal sleep and whether this synchronization is affected by other sleep regulating factors. To investigate these questions we compared sleep EEG and sleep-related free renin levels in 48 normal women and men 19-69 years old between nights before and after 40 h of sleep deprivation. During the recovery night, four bolus injections of either GHRH, CRH or placebo were injected via long catheter around sleep onset. When compared to baseline after each of the treatments SWS, SWA and renin levels increased. The characteristical oscillation profiles of renin during normal sleep were also preserved after sleep deprivation. Similar to normal sleep our data support also a distinct link between nocturnal renin secretion and SWS after sleep deprivation and that independent of the applied treatments.

Sleep in pituitary insufficient patients compared to patients with depression and healthy controls at baseline and after challenge with CRH

Sleep disturbances are prevalent in both patients with pituitary insufficiency and with depression. The role of corticotropin releasing hormone (CRH), involved in sleep regulation, has not been fully clarified. Pituitary insufficiency is an ideal model for studying sleep-endocrine effects since no consecutive hormone releases and feedback effects occur after hormone administration. 11 male patients with a chronic insufficiency of the anterior pituitary gland (PI) and under stable hormonal substitution were studied during three consecutive nights in the sleep laboratory. The first night served for adapting to laboratory setting, during the second night placebo was administered and during the third night 4 × 50 μg CRH were injected in pulsatile fashion. Sleep parameters were additionally compared with those of 15 healthy male controls (C) and 15 male patients with depression (D). CRH administration was associated with a numerical increase of wake time (115 ± 15 to 131 ± 13 min) and a decrease of REM sleep (89 ± 8 to 80 ± 8 min), REM latency (69 ± 14 to 55 ± 9 min) and slow wave sleep (66 ± 16 to 57 ± 15 min). Yet, none of these changes reached statistical significance. PI showed a worse sleep profile as compared to both control groups, e.g. indicated by a significantly lower sleep efficiency index (PI:0.80 ± 0.03 vs. C:0.94 ± 0.01 vs. D:0.87 ± 0.03). In conclusion sleep-EEG changes after CRH in PI patients resemble those found in in part in patients with depression. Sleep in anterior pituitary insufficiency was impaired despite full hormonal substitution possibly suggesting an alteration of the receptor organisation of brain structures involved in sleep regulation.

Cortisol, DHEA and DHEA-S during exposure therapy in patients with obsessive-compulsive disorder - secretion patterns and prediction of treatment response

The cortisol response in patients with obsessive-compulsive disorder (OCD) during exposure with response prevention (ERP), a stressful but very effective psychotherapeutic treatment, has shown contradictory findings in three prior studies with low sample sizes. In a larger cohort of 51 patients with OCD we repeatedly measured subjective units of distress (SUD) and the adrenocortical stress hormones cortisol, dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) in saliva during the very first session of ERP and on the day before. Expectedly, SUD were increased on the ERP day before the session and further rose during ERP, but salivary cortisol and DHEA were statistically indistinguishable from the comparison condition. Interestingly, DHEA-S was significantly elevated throughout the ERP versus the comparison day, but did not further increase in acute response to ERP. According to an explorative analysis in a subsample, hormone levels on the comparison or the ERP day did not predict anti-OCD treatment response one month later. These results corroborate our prior findings of cortisol non-response despite considerable subjective stress in ERP. The role of DHEA-S in anticipatory anxiety and the effects of augmentative cortisol therapy in ERP need further study.

Copeptin in CCK-4-induced panic in healthy man: Sexual dimorphisms in secretion pattern and panic response, but no correlation of copeptin with panic symptoms

Copeptin, the C-terminal part of the hypothalamic arginine vaspopressin (AVP) precursor, closely mirrors the production of AVP and was proposed as an easily measured novel marker of the individual stress level in man. First data in male volunteers proposed copeptin as a potential endocrine surrogate marker of cholecystokinin-tetrapeptide (CCK-4)-induced panic. We tried to replicate these pilot data and to extend them to the other sex. 46 healthy human subjects (29 men, 17 women) were given an intravenous bolus of 50 μg CCK-4. Basal and stimulated plasma copeptin was measured and panic symptoms were assessed using the Acute Panic Inventory (API). Basal copeptin was significantly lower in women vs. men, while men showed a significantly higher CCK-4-induced increase of copeptin. In contrast, female subjects displayed a signifcantly higher increase of API ratings by CCK-4. No significant correlations of panic symptoms and copeptin release induced by CCK-4 could be found, neither in man, nor in women, nor in the total sample. A sexual dimorphism in copeptin secretion and in panic response was demonstrated. Prior unexpected findings of copeptin release as an objective read-out of panic could not be replicated. The role of the vasopressinergic system in panic anxiety needs further study in panic patients and in healthy man, using also other panic provocation paradigms.

Cure of Underactive and Overactive Bladder Symptoms in Women by 1,671 Apical Sling Operations Gives Fresh Insights into Pathogenesis and Need for Definition Change

INTRODUCTION

To check evidence that symptoms identical with those constituting "underactive bladder" (UAB) and "overactive bladder" (OAB) are caused by apical prolapse and cured by repair thereof.

MATERIAL AND METHODS

After repair of apical prolapse by mesh tape reinforcement of lax uterosacral ligaments (USL) data form 1,671 women were retrospectively examined to determine the presence of OAB and UAB symptoms and to check, how many were cured surgically. Thereby 3 different techniques were performed: elevate (n = 277), "Posterior IVS" (n = 1,049), and TFS cardinal (CL)/USL (n = 345).

RESULTS

Symptoms identical with those comprising UAB and OAB were cured in up to 80% of cases following surgical repair of the CL/USL complex.

CONCLUSIONS

These symptoms may be consistent with symptoms of the posterior fornix syndrome, which comprises 4 main symptoms: micturition difficulties, urge/frequency, nocturia, chronic pelvic pain, all consequent on USL laxity. Surgical cure of OAB and UAB is inconsistent with existing definitions, which imply pathogenesis of the detrusor muscle itself. A reconsideration and reformulation of existing definitions may be required. Altering UAB definition to "bladder emptying difficulties" and return to former definitions for OAB such as "detrusor" or "bladder instability" may help to restore compatibility with surgical cure of these conditions.

Clinical score system in the treatment of Cushing's disease: failure to identify discriminative variables from the German Cushing's Registry

PURPOSE

To develop a multidimensional and integrated clinical scoring instrument, that encompasses, summarizes and weights appropriately the desired clinical benefits of a treatment for Cushing's disease (CD).

METHODS

A panel of 42 variables potentially relevant to the clinical course of CD was predefined by endocrinology experts taking into account relevant literature. Variables as well as biochemical disease activity assessed as urinary free cortisol (UFC) levels were evaluated at baseline and at least after 12 months in patients treated between 2012 and 2016 in two Munich-based academic centres of the German Cushing's Registry. The primary endpoint was the identification of variables whose changes from baseline to follow-up visit(s) could characterize well biochemical cured from not cured patients after 12 months.

RESULTS

Ninety nine patients with at least two consecutive visits were enrolled. Biochemical data were available for 138 visit-pairs among which UFC was not controlled in 48 (34.8%) and controlled in 90 (65.2%) first visits. In 41 (29.7%) consecutive visits (visit-pairs) changes in biochemical activity categories was observed between visits; concretely: in 17 (12.3%) consecutive visits changing from previously controlled to not controlled, and in 24 (17.4%) from uncontrolled to controlled biochemical activity. Multivariate statistical analyses (especially analyses of variance) based on data of the 138 visit-pairs were performed in order to proof possible effects of biochemical activity on clinical benefits. However, in none of the considered 42 variables corresponding to quality of life-dimensions, laboratory, anthropometric, musculo-skeletal or other clinical areas any statistically significant differences between different categories of biochemical activity were observed.

CONCLUSION

It was not possible to provide clinical key parameters in our population of patients with CD discriminating biochemical cured from non-cured patients and to construct a clinical scoring system reflecting clinical treatment benefits.

Impact of physical or sexual childhood abuse on plasma DHEA, DHEA-S and cortisol in a low-dose dexamethasone suppression test and on cardiovascular risk parameters in adult patients with major depression or anxiety disorders

While the impact of childhood trauma on basal and dynamic cortisol regulation has widely been studied, the most abundant steroid hormones dehydroepiandrosterone (DHEA) and its sulphated derivative DHEA-S have received little attention in this context. One-hundred in-door patients suffering from major depression or an anxiety disorder filled in the Childhood Trauma Questionaire. A low dose dexamethasone suppression test (DST) measuring DHEA, DHEA-S and cortisol was performed. Furthermore, various cardiovascular risk parameters were measured. Forty-six percent of the patients reported a history of substantial physical or sexual childhood abuse. However, no significant differences in plasma DHEA or DHEA-S emerged in the DST between the traumatised group and the remaining patients. Basal plasma cortisol was significantly lower in the childhood trauma group. No impact of childhood trauma history on cardiovascular risk factor profile was detected. Current limited data about DHEA or DHEA-S in patients with childhood trauma are equivocal. Further study using more sophisticated assessment of trauma history and simultaneously measuring a multitude of putative biomarkers of traumatization are needed.

Sleep after intranasal progesterone vs. zolpidem and placebo in postmenopausal women - A randomized, double-blind cross over study

CONTEXT

The loss of progesterone during menopause is linked to sleep complaints of the affected women. Previously we demonstrated sleep promoting effects of oral progesterone replacement in postmenopausal women. The oral administration of progesterone, however, is compromised by individual differences in bioavailability and metabolism of the steroid.

OBJECTIVE

We compared the sleep-endocrine effects after intranasal progesterone (MPP22), zolpidem and placebo in healthy postmenopausal women.

DESIGN

This was a randomized double-blind cross-over study.

SETTING

German monocentric study PARTICIPANTS: Participants were 12 healthy postmenopausal women.

INTERVENTIONS

Subjects received in randomized order four treatments, 2 doses of intranasal progesterone (4.5 mg and 9 mg of MPP22), 10 mg of zolpidem and placebo.

OUTCOME MEASURES

Main outcome were conventional and quantitative sleep-EEG variables. Secondary outcomes were the subjective sleep variables and the sleep related concentrations of cortisol, growth hormone (GH), melatonin and progesterone.

RESULTS

Sleep promoting effects were found after the higher dosage of MPP22 and after zolpidem. Zolpidem prompted benzodiazepine-like effects on quantitative sleep EEG as expected, whereas no such changes were found after the two dosages of MP22. Nocturnal progesterone levels increased after 9.0 mg MPP22. No other changes of hormone secretion were found.

CONCLUSIONS

Our study shows sleep promoting effects after intranasal progesterone. The spectral signature of intranasal progesterone did not resemble the sleep-EEG alterations induced by GABA active compounds. Progesterone levels were elevated after 9.0 mg MPP22. No other endocrine effects were observed.

Effects of 35% carbon dioxide (CO2) inhalation in patients with post-traumatic stress disorder (PTSD): A double-blind, randomized, placebo-controlled, cross-over trial

BACKGROUND

In patients with post-traumatic stress disorder (PTSD) two open pilot studies about the effects of 35% carbon dioxide (CO₂) exist. One shows an augmented panicogenic and anxiogenic response (Muhtz et al., 2011), the other does not (Talesnik et al. 2007). We further characterized the CO₂ reactivity in PTSD using for the first time placebo-controlled and double-blind conditions.

METHODS

In 20 patients with PTSD we assessed panic, anxiety, dissociative and PTSD symptoms after a single vital capacity inhalation of 35% CO₂ compared to a placebo gas condition in a within-participant cross-over, placebo-controlled, double-blind and randomized design.

RESULTS

Inhalation of 35% CO₂ versus placebo provoked significantly increased panic, anxiety, dissociative and PTSD symptoms. The reaction to placebo gas was minimal. Order of inhalation, patients' sex or age did not influence the results. The panic and anxiety response under CO₂ was considerably higher in the PTSD patients than in healthy controls from our previous open study.

CONCLUSIONS

The results corroborate that our preceding findings of an increased CO₂ reactivity in patients with PTSD are not false positive due to the open design or the lack of placebo control. Replication in a larger number of PTSD patients and matched control subjects is needed. The potential role of childhood traumatisation, psychiatric comorbidity, psychotropic medication and trait dissociation in prior contradictory reports should be clarified.

Copeptin - A potential endocrine surrogate marker of CCK-4-induced panic symptoms?

Intravenous cholecystokinin-tetrapeptide (CCK-4) administration reliably and dose-dependently provokes panic anxiety in man, accompanied by adrenocorticotropic hormone (ACTH) and cortisol release. Preclinical findings suggest that behavioral and endocrine effects of CCK-4 are mediated via corticotropin-releasing hormone (CRH) release. Anxiogenic stimulation of the central CCK-receptors in man was shown to increase as well vasopressin (AVP), which acts synergistically with CRH as pituitary-adrenocortical axis stimulator during stress. Copeptin (CoP), the C-terminal part of pre-pro-AVP, is released in an equimolar ratio to AVP. It is more stable in the circulation and easier to determine than AVP and it was found to closely mirror the production of AVP. So far, CoP secretion has not been characterized during panic provocation. In 30 healthy male human subjects, we repeatedly measured CoP in plasma during a panic challenge and studied its correlation to Acute Panic Inventory (API) ratings and plasma ACTH and cortisol. CoP levels correlated positively with the increase in API ratings (r=0.41, p=0.03), while ACTH or cortisol did not (r=0.08, p=0.68 and r=0.12, p=0.53, respectively). CoP levels correlated also positively with ACTH (r=0.48, p=0.009) and cortisol (r=0.48, p=0.01) concentrations throughout the CCK-4 challenge. As expected, we found a positive correlation between plasma ACTH and cortisol levels (r=0.57, p=0.001). A vasopressinergic activation during CCK-4 induced panic was demonstrated, which was correlated positively to panic symptoms and pituitary-adrenocortical release. Our findings suggest a role of CoP as a potential surrogate marker of CCK-4 panic symptoms. Further studies are needed to replicate our results and to further clarify the role of CoP as a stress-sensitive hormone in different panic paradigms as well as in panic patients.

Corticotropin-releasing hormone induces depression-like changes of sleep electroencephalogram in healthy women

We reported previously that repetitive intravenous injections of corticotropin-releasing hormone (CRH) around sleep onset prompt depression-like changes in certain sleep and endocrine activity parameters (e.g. decrease of slow-wave sleep during the second half of the night, blunted growth hormone peak, elevated cortisol concentration during the first half of the night). Furthermore a sexual dimorphism of the sleep-endocrine effects of the hormones growth hormone-releasing hormone and ghrelin was observed. In the present placebo-controlled study we investigated the effect of pulsatile administration of 4×50μg CRH on sleep electroencephalogram (EEG) and nocturnal cortisol and GH concentration in young healthy women. After CRH compared to placebo, intermittent wakefulness increased during the total night and the sleep efficiency index decreased. During the first third of the night, REM sleep and stage 2 sleep increased and sleep stage 3 decreased. Cortisol concentration was elevated throughout the night and during the first and second third of the night. GH secretion remained unchanged. Our data suggest that after CRH some sleep and endocrine activity parameters show also depression-like changes in healthy women. These changes are more distinct in women than in men.

Mental Health in Offspring of Traumatized Refugees with and without Post-traumatic Stress Disorder

Intergenerational transmission of psychological trauma and the impact of parental post-traumatic stress disorder (PTSD) on offspring are controversially discussed. We studied 50 offspring (36 women and 14 men, mean age 42.1 years) of refugees who were severely traumatized as children at the end of World War II. From these, 25 of the refugees currently suffered from chronic PTSD, and 25 had no PTSD. Parental PTSD status did not significantly influence mental health [as per the Symptom Checklist (SCL)-90-R] or quality of life (assessed by the 36-item Short-form Health Survey) in their children. In the entire sample, frequency of talking with the mother about the flight correlated with phobic anxiety (r = 0.67, p = 0.03). Interestingly, the stated burden of having a parent with a history of flight significantly (p < 0.05) correlated with almost all subscales of the SCL-90-R. These results in a non-clinical sample do not support a specific role of parental PTSD in intergenerational trauma transmission. Our other remarkable, but preliminary, results need to be studied in larger samples using more subtle interaction or schema analyses. Copyright © 2015 John Wiley & Sons, Ltd.

Adrenocorticotropic hormone in serial cerebrospinal fluid in man - Subject to acute regulation by the hypothalamic-pituitary-adrenocortical system?

Acute regulation of adrenocorticotropic hormone (ACTH) in cerebrospinal fluid (CSF) by the hypothalamic-pituitary-adrenocortical system has not been investigated in man. In a pilot study in healthy male volunteers we measured ACTH every twenty minutes in serial CSF for three hours after an intravenous placebo, hydrocortisone (100mg) or insulin (2mg/kg) injection. No acute inhibitory or stimulatory effects of these interventions were discovered. Our results corroborate previous findings in rhesus monkeys. The regulation of CSF ACTH and its potential relevance for behavioral alterations in health and disease (e.g. major depression or anorexia nervosa) in humans need further study.

Does Pregnenolone Enhance Exposure Therapy in Obsessive-Compulsive Disorder? - A Pilot, Interim Report of a Randomized, Placebo-Controlled, Double-Blind Study

Exposure therapy is an effective cognitive-behavioral treatment for patients with obsessive-compulsive disorder (OCD). However, a further amelioration of symptoms by additional drugs that enhance extinction learning is desirable. An interesting candidate is pregnenolone, which positively modulates NMDA and GABAA receptors in preclinical studies and influences amygdala and prefrontal activity in humans. We present pilot data showing high acceptance and good tolerability of pregnenolone given 2 h before exposure sessions in OCD patients. As per our interim analyses, exposure treatment resulted in significantly improved main outcome parameters, but no effects of pregnenolone vs. placebo pretreatment were detectable thus far.

Overnight suppression of HPA axis after mineraolocorticoid receptor stimulation: A sleep endocrine study

Nocturnal hyperactivity of hypothalamic-pituitary-adrenal axis (HPA) indicates decreased feedback inhibition with stress-related conditions such as major depression and sleep disorders. To characterize the role of mineralocorticoid (MR) in regulation of HPA axis activity during nocturnal sleep and involvement in sleep architecture, we investigated sleep endocrine effects of the MR agonist fludrocortisone in healthy men after pretreatment with metyrapone to minimize the impact of endogenous cortisol. Subjects (n=8) were treated on three occasions in a single-blinded design in random order with a) metyrapone, b) fludrocortisone after metyrapone, and c) placebo. Polysomnography was recorded and blood samples were drawn for determination of adrenocorticotropic hormone (ACTH) and cortisol during the entire night. After metyrapone administration ACTH was significantly enhanced, while overall nocturnal cortisol secretion remained largely unchanged. Whereas administration of fludrocortisone induced a significant inhibitory effect on basal ACTH and cortisol secretion, no considerable effects on sleep pattern were detectable. While the involvement of MR in sleep regulation needs further study, endocrine findings underline the role of MR in tonic regulation of HPA axis during nocturnal sleep and demonstrate the ability of fludrocortisone to further suppress HPA axis activity overnight. Additional studies would be required to evaluate endocrine and clinical fludrocortisone effects in depressive patients showing HPA hyperactivity.

Interferon β-1a reduces increased interleukin-16 levels in multiple sclerosis patients

OBJECTIVES

There is convergent evidence for an important role of interleukin-16 (IL-16) in the pathogenesis of multiple sclerosis (MS). IL-16 serves as a chemoattractant for different immune cells that are involved in developing lesions. Here, we compared IL-16 levels of MS patients and controls and addressed the long-term effect of IFN-β, the most common immunomodulatory MS therapy, on IL-16 serum levels in MS patients over 2 years. Beyond this, we analysed the expression of IL-16 in two CD4(+) T-cell subsets, Th1 and Th17 cells, which are important autoimmune mediators and affected by IFN-β treatment, derived from myelin-specific T-cell transgenic mice.

MATERIALS AND METHODS

IL-16 serum levels of 17 controls and of 16 MS patients before therapy and at months 1, 2, 3, 6, 9, 12 and 24 during IFN-β1a therapy were determined by ELISA. MRI was performed before therapy, at months 12 and 24. IL-16 expression of in vitro differentiated murine myelin oligodendrocyte glycoprotein (MOG)-specific Th1 and Th17 cells was quantified by real-time PCR.

RESULTS

Before therapy, MS patients showed significantly elevated IL-16 levels compared with controls irrespective of disease activity determined by MRI. Therapy with IFN-β1a led to a significant linear decrease in IL-16 serum levels beginning after 2 months. MOG-specific Th17 cells expressed more IL-16 than Th1 cells.

CONCLUSIONS

Reduction in increased IL-16 levels may be of relevance for the therapeutic effect of IFN-β1a in MS. Easily accessible IL-16 serum levels hold a potential as biomarker of treatment efficacy in MS.

No acute suppression of cerebrospinal fluid corticotropin-releasing hormone in man by cortisol administration

Corticotropin-releasing hormone (CRH) in cerebrospinal fluid (CSF) is regarded as index of brain endocrine and behavioral functioning. We investigated the acute effects of intravenous cortisol (100mg) vs. placebo on serial CSF CRH in ten healthy men. CSF CRH concentrations were not significantly suppressed by cortisol within 3h. The origin and regulation of CSF CRH need further research.

Psychiatric patient stratification using biosignatures based on cerebrospinal fluid protein expression clusters

Psychiatric disorders are caused by perturbed molecular pathways that affect brain circuitries. The identification of specific biosignatures that are the result of altered pathway activities in major depression, bipolar disorder and schizophrenia can contribute to a better understanding of disease etiology and aid in the implementation of diagnostic assays. In the present study we identified disease-specific protein biosignatures in cerebrospinal fluid of depressed (n: 36), bipolar (n: 27) and schizophrenic (n: 35) patients using the Reverse Phase Protein Microarray technology. These biosignatures were able to stratify patient groups in an objective manner according to cerebrospinal fluid protein expression patterns. Correct classification rates were over 90%. At the same time several protein sets that play a role in neuronal growth, proliferation and differentiation (NEGR1, NPDC1), neurotransmission (SEZ6) and protection from oxidative damage (GPX3) were able to distinguish diseased from healthy individuals (n: 35) indicating a molecular signature overlap for the different psychiatric phenotypes. Our study is a first step toward implementing a psychiatric patient stratification system based on molecular biosignatures. Protein signatures may eventually be of use as specific and sensitive biomarkers in clinical trials not only for patient diagnostic and subgroup stratification but also to follow treatment response.

No effects of antidepressants on negative symptoms in schizophrenia

Negative symptoms are common in schizophrenia, but often difficult to differentiate from depression. They are associated with long-term impairment and do not respond well to current treatment approaches. Even though antidepressants are commonly prescribed in schizophrenia, their beneficial effect is still under debate. In the present study, we aimed to investigate the effect of serotonergic versus noradrenergic antidepressant add-on therapy on negative symptoms in schizophrenia. Fifty-eight patients with schizophrenia according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria and with predominant negative symptoms were randomized in a double-blind design to add-on treatment with citalopram, reboxetine, or placebo for 4 weeks. Analysis of covariance with repeated-measures design was used to compare improvement between treatment groups in scores of the Positive and Negative Syndrome Scale and the Hamilton Rating Scale for Depression. A χ² test was used to compare responder rates between treatment groups. Repeated-measures analysis of covariance revealed no differences between treatment groups over time (treatment × time, not statistically significant) for Positive and Negative Syndrome Scale subscales. Although a subgroup analysis in subjects fulfilling the criteria for minor depression was suggestive of higher responder rates in the citalopram group compared with reboxetine, the results did not reach significance level. Our findings do not support a beneficial effect of adjunctive antidepressant treatment on negative symptoms in schizophrenia. However, depressive symptoms are reduced in patients with minor depression by citalopram but not reboxetine, which is in line with previous findings.

Prognostic and symptomatic aspects of rapid eye movement sleep in a mouse model of posttraumatic stress disorder

Not every individual develops Posttraumatic Stress Disorder (PTSD) after the exposure to a potentially traumatic event. Therefore, the identification of pre-existing risk factors and early diagnostic biomarkers is of high medical relevance. However, no objective biomarker has yet progressed into clinical practice. Sleep disturbances represent commonly reported complaints in PTSD patients. In particular, changes in rapid eye movement sleep (REMS) properties are frequently observed in PTSD patients. Here, we examined in a mouse model of PTSD whether (1) mice developed REMS alterations after trauma and (2) whether REMS architecture before and/or shortly after trauma predicted the development of PTSD-like symptoms. We monitored sleep-wake behavior via combined electroencephalogram/electromyogram recordings immediately before (24 h pre), immediately after (0-48 h post) and 2 months after exposure to an electric foot shock in male C57BL/6N mice (n = 15). PTSD-like symptoms, including hyperarousal, contextual, and generalized fear, were assessed 1 month post-trauma. Shocked mice showed early onset and sustained elevation of REMS compared to non-shocked controls. In addition, REMS architecture before trauma was correlated with the intensity of acoustic startle responses, but not contextual fear, 1 month after trauma. Our data suggest REMS as prognostic (pre-trauma) and symptomatic (post-trauma) marker of PTSD-like symptoms in mice. Translated to the situation in humans, REMS may constitute a viable, objective, and non-invasive biomarker in PTSD and other trauma-related psychiatric disorders, which could guide pharmacological interventions in humans at high risk.

Differential effects to CCK-4-induced panic by dexamethasone and hydrocortisone

OBJECTIVES

Peripheral administration of the cholecystokinin (CCK) receptor agonist CCK-4 generates panic and activates the hypothalamic-pituitary-adrenal (HPA) axis. Direct effects at the pituitary and CCK-HPA interactions at higher regulatory sites have been suggested. According to preliminary data, ACTH response to CCK receptor agonists may differ from its response to exogenous CRH by its resistance to cortisol feedback inhibition. To further explore this resistance and to better characterize CCK-4 sites of action, the effects of different glucocorticoid pretreatments on CCK-4-induced panic were compared.

METHODS

Using a double-blind placebo-controlled design we pretreated healthy males with either dexamethasone (peripheral action) or hydrocortisone (central-peripheral action) each followed by a CCK-4 challenge. Blood levels of ACTH and cortisol were analyzed and panic symptoms were assessed.

RESULTS

We found a blunted response of ACTH release following CCK-4 injection only after hydrocortisone pretreatment. Dexamethasone however did not affect CCK-4-induced ACTH release relative to baseline. In contrast to dexamethasone, hydrocortisone reduced the severity of CCK-4-induced panic as measured by the Acute Panic Inventory on a trend level.

CONCLUSIONS

Findings suggest that CCK-4-induced stress hormone release seems susceptible to cortisol-feedback inhibition and argues for a suprapituitary site of CCK action. Effects on panic anxiety were weak but congruent with studies showing that CCK-4-induced HPA axis inhibition is accompanied by a reduction of anxiety after CCK-4.

Non-response of cortisol during stressful exposure therapy in patients with obsessive-compulsive disorder--preliminary results

Exposure with response prevention (ERP) is an established treatment for patients with obsessive-compulsive disorder (OCD) and also an interesting model to characterize neuroendocrine response to psychological stress. However, so far few studies have assessed hypothalamic-pituitary-adrenocortical (HPA) function during ERP and results are inconsistent. In 15 patients with OCD we repeatedly measured salivary cortisol and subjective units of distress (SUD) on two consecutive afternoons. The first day served as a comparison condition; on the second day the very first session of ERP took place. While SUD were significantly increased during ERP versus the comparison day, salivary cortisol was statistically indistinguishable between ERP and comparison conditions before, during and after ERP. Thus, despite considerable psychological stress no increase of cortisol was observed. This response pattern to ERP in OCD patients needs further research.

Polymorphisms of the drug transporter gene ABCB1 predict side effects of treatment with cabergoline in patients with PRL adenomas

INTRODUCTION

Treatment with dopamine agonists in patients with prolactin (PRL) adenomas and Parkinson's disease is associated with central side effects. Central side effects may depend on a substance's ability to pass the blood-brain barrier, which can be actively controlled by transporter molecules such as the P-glycoprotein (P-gp) encoded by the ABCB1 gene.

MATERIALS AND METHODS

We aimed to determine whether cabergoline is transported by the P-gp and whether polymorphisms of its encoding ABCB1 gene predict central side effects of cabergoline therapy in patients with PRL adenomas. i) In an experimental mouse model lacking the homologues of the human ABCB1 gene (Abcb1ab double knockout mouse model), we examined whether cabergoline is a substrate of the P-gp using eight mutant and eight wild-type mice. ii) In a human case-control study including 79 patients with PRL adenomas treated with cabergoline at the Max Planck Institute of Psychiatry in Munich, we investigated the association of four selected ABCB1 gene single nucleotide polymorphisms (SNPs) (rs1045642, rs2032582, rs2032583 and rs2235015), with the occurrence of central side effects under cabergoline therapy.

RESULTS

i) In the experimental mouse model, we observed that brain concentrations of cabergoline were tenfold higher in the mutant mice compared with their wild-type littermates, implying that cabergoline is indeed a substrate of the transporter P-gp at the blood-brain barrier level. ii) In the human study, we observed significant negative associations under cabergoline for the C-carriers and heterozygous CT individuals of SNP rs1045642 with two central side effects (frequency of fatigue and sleep disorders) and for the G-carriers of SNP rs2032582 with the enhancement of dizziness. For the SNPs rs2235015 and rs2032583, no associations with central side effects under cabergoline were found.

DISCUSSION

This is the first study demonstrating that individual ABCB1 gene polymorphisms, reflecting a different expression and function of the P-gp, could predict the occurrence of central side effects under cabergoline. Our findings can be viewed as a step into personalised therapy in PRL adenoma patients.

Ghrelin levels increase after pictures showing food

The neuropeptide ghrelin is a major signal for food intake in various species including humans. After exogenous ghrelin administration, food intake and body weight increase in rodents. In normal human subjects, ghrelin administration increases self-rated appetite and calorie intake and prompts the imagination of favorite meals. It is unclear so far whether ghrelin levels are affected by external cues such as sight of food. We investigated the influence of pictures showing food compared to neutral pictures on ghrelin levels in young normal male subjects (n = 8). The study consisted of two consecutive sessions with a one-week interval. During each session, blood for later analysis of plasma concentrations of ghrelin was collected between 08:15 and 13:00 every 15 min (between 10:30 and 11:30 every 10 min). Breakfast and lunch was provided at 08:30 and 12:00, respectively. Fifty pictures were presented from 10:30 to 10:45 showing neutral images during the first session and food contents during the second session. As expected, ghrelin levels increased before each meal independent of the picture contents. In addition, ghrelin levels during the 30-min interval following the presentation of pictures with food increased significantly compared to the 30-min interval before this presentation (area under the curve (AUC): 188 % vs. 158 %, P < 0.05). The difference in the increases between the two picture conditions was also significant (P < 0.05). Our findings suggest that sight of food elevates ghrelin levels in healthy volunteers.

A new way of identifying biomarkers in biomedical basic-research studies

A simple, nonparametric and distribution free method was developed for quick identification of the most meaningful biomarkers among a number of candidates in complex biological phenomena, especially in relatively small samples. This method is independent of rigid model forms or other link functions. It may be applied both to metric and non-metric data as well as to independent or matched parallel samples. With this method identification of the most relevant biomarkers is not based on inferential methods; therefore, its application does not require corrections of the level of significance, even in cases of thousands of variables. Hence, the introduced method is appropriate to analyze and evaluate data of complex investigations in clinical and pre-clinical basic research, such as gene or protein expressions, phenotype-genotype associations in case-control studies on the basis of thousands of genes and SNPs (single nucleotide polymorphism), search of prevalence in sleep EEG-Data, functional magnetic resonance imaging (fMRI) or others.

Proteomics and metabolomics analysis of a trait anxiety mouse model reveals divergent mitochondrial pathways

BACKGROUND

Although anxiety disorders are the most prevalent psychiatric disorders, no molecular biomarkers exist for their premorbid diagnosis, accurate patient subcategorization, or treatment efficacy prediction. To unravel the neurobiological underpinnings and identify candidate biomarkers and affected pathways for anxiety disorders, we interrogated the mouse model of high anxiety-related behavior (HAB), normal anxiety-related behavior (NAB), and low anxiety-related behavior (LAB) employing a quantitative proteomics and metabolomics discovery approach.

METHODS

We compared the cingulate cortex synaptosome proteomes of HAB and LAB mice by in vivo (15)N metabolic labeling and mass spectrometry and quantified the cingulate cortex metabolomes of HAB/NAB/LAB mice. The combined data sets were used to identify divergent protein and metabolite networks by in silico pathway analysis. Selected differentially expressed proteins and affected pathways were validated with immunochemical and enzymatic assays.

RESULTS

Altered levels of up to 300 proteins and metabolites were found between HAB and LAB mice. Our data reveal alterations in energy metabolism, mitochondrial import and transport, oxidative stress, and neurotransmission, implicating a previously nonhighlighted role of mitochondria in modulating anxiety-related behavior.

CONCLUSIONS

Our results offer insights toward a molecular network of anxiety pathophysiology with a focus on mitochondrial contribution and provide the basis for pinpointing affected pathways in anxiety-related behavior.

Effects of chronic posttraumatic stress disorder on metabolic risk, quality of life, and stress hormones in aging former refugee children

It is still unclear whether the association between traumatic stress and physical disease is mediated by posttraumatic stress disorder (PTSD). Therefore, we examined the long-term consequences of PTSD on cardiovascular risk, stress hormones, and quality of life in a sample of former refugee children who were severely traumatized more than six decades ago. In 25 subjects with chronic PTSD and 25 trauma-controlled subjects, we measured the variables of metabolic syndrome supplemented by the ankle-brachial index and highly sensitive C-reactive protein. Quality of life was assessed using the 36-item Short-Form Health Survey. Cortisol, adrenocorticotropin-releasing hormone (ACTH), and dehydroepiandrosterone (DHEA) were measured using the low-dose-dexamethasone suppression test. In addition, salivary cortisol was assessed at 8:00 a.m., 12:00 p.m., 4:00 p.m., and 8:00 p.m. We found a significant group effect between participants with and without PTSD regarding quality of life but not in any metabolic parameter including the ankle-brachial index or cortisol, ACTH, and DHEA in plasma before and after dexamethasone or salivary cortisol. The postulated association between traumatic stress and physical illness does not appear to be mediated by PTSD in this population. Nevertheless, the search for subgroups of PTSD patients with childhood traumatization leading to different metabolic and endocrine long-term consequences in aging PTSD patients is needed.

Acute panicogenic, anxiogenic and dissociative effects of carbon dioxide inhalation in patients with post-traumatic stress disorder (PTSD)

BACKGROUND

Increased anxiety and panic to inhalation of carbon dioxide (CO(2)) has been described in patients with anxiety disorders, especially panic disorder, compared to healthy subjects. Post-traumatic stress disorder (PTSD) has been hypothesised to resemble panic disorder and is currently classified as an anxiety disorder in DSM-IV. However, there are only very few data available about the sensitivity of patients with PTSD to CO(2).

METHODS

In 10 patients with PTSD, 10 sex- and age-matched healthy subjects and 8 patients with panic disorder we assessed anxiety, panic, dissociative and PTSD symptoms before and after a single vital capacity inhalation of 35% CO(2).

RESULTS

Patients with PTSD showed an increased anxiety, panic and dissociative reaction to the inhalation of 35% CO(2) compared to healthy participants. PTSD subjects' responses were indistinguishable from those of panic patients. Additionally, PTSD-typical symptoms like post-traumatic flashbacks were provoked in patients with PTSD after the inhalation of CO(2).

CONCLUSIONS

In our sample, PTSD was associated with an increased CO(2) reactivity, pointing to an increased susceptibility of PTSD patients to CO(2) challenge.

Sleep disturbances in highly stress reactive mice: modeling endophenotypes of major depression

Background

Neuronal mechanisms underlying affective disorders such as major depression (MD) are still poorly understood. By selectively breeding mice for high (HR), intermediate (IR), or low (LR) reactivity of the hypothalamic-pituitary-adrenocortical (HPA) axis, we recently established a new genetic animal model of extremes in stress reactivity (SR). Studies characterizing this SR mouse model on the behavioral, endocrine, and neurobiological levels revealed several similarities with key endophenotypes observed in MD patients. HR mice were shown to have changes in rhythmicity and sleep measures such as rapid eye movement sleep (REMS) and non-REM sleep (NREMS) as well as in slow wave activity, indicative of reduced sleep efficacy and increased REMS. In the present study we were interested in how far a detailed spectral analysis of several electroencephalogram (EEG) parameters, including relevant frequency bands, could reveal further alterations of sleep architecture in this animal model. Eight adult males of each of the three breeding lines were equipped with epidural EEG and intramuscular electromyogram (EMG) electrodes. After recovery, EEG and EMG recordings were performed for two days.

Results

Differences in the amount of REMS and wakefulness and in the number of transitions between vigilance states were found in HR mice, when compared with IR and LR animals. Increased frequencies of transitions from NREMS to REMS and from REMS to wakefulness in HR animals were robust across the light-dark cycle. Detailed statistical analyses of spectral EEG parameters showed that especially during NREMS the power of the theta (6-9 Hz), alpha (10-15 Hz) and eta (16-22.75 Hz) bands was significantly different between the three breeding lines. Well defined distributions of significant power differences could be assigned to different times during the light and the dark phase. Especially during NREMS, group differences were robust and could be continuously monitored across the light-dark cycle.

Conclusions

The HR mice, i.e. those animals that have a genetic predisposition to hyper-activating their HPA axis in response to stressors, showed disturbed patterns in sleep architecture, similar to what is known from depressed patients. Significant alterations in several frequency bands of the EEG, which also seem to at least partly mimic clinical observations, suggest the SR mouse lines as a promising animal model for basic research of mechanisms underlying sleep impairments in MD.

Effects of ghrelin on psychopathology, sleep and secretion of cortisol and growth hormone in patients with major depression

Ghrelin showed antidepressant-like effects in mice. Furthermore, ghrelin influences sleep and the activity of hypothalamic-pituitary-adrenal (HPA) and somatotropic axis in healthy humans as indicated by increased cortisol and growth hormone (GH) plasma levels. Both sleep and the activity of these endocrine axes are disturbed in depression. We therefore studied the impact of ghrelin on psychopathology, sleep and secretion of cortisol and GH in patients with major depression. Depressive symptoms as assessed by a validated self rating scale ('Befindlichkeits-Skala', [mental state scale]), secretion profiles of cortisol and GH and sleep-EEGs were determined in 14 unmedicated patients with major depression (7 women) twice, receiving 50 μg ghrelin or placebo at 22:00, 23:00, 00:00, and 01:00 hours. Overall, depressive symptoms did not change significantly after ghrelin administration (placebo: 37 ± 8; ghrelin: 33 ± 10, p = 0.178). However, there was an improvement at trend level in men (placebo: 36 ± 9 to ghrelin: 30 ± 9, p = 0.093) but not in women. In men, ghrelin was associated with less time awake (placebo: 149.0 ± 11.1; ghrelin: 88.0 ± 12.2 min, p = 0.029) and more non-REM sleep (placebo: 263.2 ± 24.1; ghrelin: 304.9 ± 14.1 min, p = 0.027), in women with less REM sleep (placebo: 108.6 ± 15.7; ghrelin: 74.1 ± 13.8 min, p = 0.031) and longer REM latency (placebo: 49.9 ± 6.5; ghrelin: 85.6 ± 14.1 min, p = 0.019). In both sexes, ghrelin caused strong transient increases of GH and cortisol. In conclusion, our study may provide some initial indication that ghrelin can exert antidepressant effects in patients with major depression. Ghrelin strongly affected sleep and secretion of GH and cortisol in a partly different way as previously reported in healthy subjects.

FC24-03 - Lack of cortisol response during exposure therapy in patients with obsessive-compulsive disorder

Introduction

Exposure therapy with response prevention (ERP) is the most effective treatment for patients with obsessive-compulsive disorder (OCD), but associated with considerable temporary stress during initial sessions.

Objectives

Amazingly, only scant information is available about stress hormone release during exposure therapy and its implication on therapy outcome in OCD.

Aims

To characterize hypothalamic-pituitary-adrenocortical activation during ERP treatment in OCD.

Methods

15 patients with OCD were studied twice from 13:00 to 16:00 - on the day before and of their first ERP therapy session (14:00 to 15:00). Subjective units of distress (SUD, 100 mm visual analogue scale) and salivary cortisol concentrations were assessed every 20 minutes.

Results

Before and during (but not after) ERP SUD were significantly increased versus the control day (mean SUD before ERP: 49.8 vs. 31.4, mean peak vaules during ERP: 72.6 vs. 34.0). Salivary cortisol decresed significantly during the study period (as expected according to the regular diurnal rhythm), but no significant differences between ERP and the control day were detected at any time point.

Conclusions

Despite clear-cut psychological stress before and during ERP, no increased release of cortisol was observed. Our findings resemble respective results in panic disorder. Possible neurobiological underpinnings of this unexpected regulatory pattern will be discussed. Furthermore, we will speculate on the impact of lacking cortisol response on extinction learning during ERP.

CCK-4: Psychophysiological conditioning elicits features of spontaneous panic attacks

INTRODUCTION

Cholecystokinin-tetrapeptide (CCK-4) is an established model to generate subjective panic anxiety. CCK-4 injection also results in consistent and dose-dependent rise of stress hormones. Effects other than upon subjective panic and stress hormone activity have barely been examined. The purpose of the study was to investigate CCK-4 effects on emotional facial expression and especially on fear relevant facial muscles establishing therewith a more objective method to measure subjective panic anxiety.

METHODS

20 healthy male subjects were randomly and double-blindedly assigned in two groups (dose groups), each of which was investigated three times once with placebo and twice with 25 μg or 50 μg CCK-4 respectively. Subjects of each group were randomly assigned in two different balanced orders of investigations: CCK-CCK-Placebo vs. Placebo-CCK-CCK. Facial muscle and hypothalamo-pituitary-adrenocortical (HPA)-axis activity were recorded.

RESULTS

CCK-4 led dose-dependently to an increase of panic anxiety, an activation of fear relevant facial muscles and a rise of stress hormones. Whereas placebo administration before CCK-4 revealed no significant panic and stress response, during placebo following CCK-4 stimulations a psychophysiological conditioning effect could be observed without rise in HPA-axis activity.

DISCUSSION

Our findings indicate the possibility to measure different intensities of panic anxiety and conditioning effects with a facial EMG method. Dissociation of HPA-activity and fear relevant facial muscle activity is in accordance with former results about spontaneous panic attacks.

Influence of exogenous atrial natriuretic peptide on the nocturnal hypothalamic-pituitary-adrenal axis and sleep in healthy men

Atrial natriuretic peptide (ANP), originally found in the cardiac atria, is also widely distributed in the central nervous system (CNS) and has been predominantly found in the hypothalamus and the pituitary gland. Previous in vitro and in vivo studies have provided evidence for an inhibitory control of ANP at all regulatory levels of the hypothalamo-pituitary-adrenocortical (HPA) system. In vivo studies in man demonstrated that ANP inhibits stimulated pituitary-adrenal secretion during wakefulness. On the other hand, it has been reported that various neuropeptides not only influence the neuroendocrine compound of sleep, but also exert specific effects on the sleep electroencephalogram (EEG). To further characterize the role of ANP in the regulation of the nocturnal HPA axis activity and consecutive sleep regulation, we investigated sleep-endocrine effects of intravenously administered ANP in healthy men during nocturnal sleep. Eight volunteers underwent three trial conditions in random order and in a single-blind design receiving ANP infusion at the beginning of the 1st or the 2nd half of the night, or placebo. Sleep was assessed by polysomnography and blood samples were drawn in 30-min intervals for determination of adrenocorticotrophic hormone (ACTH) and cortisol during the entire night. While the ACTH and cortisol secretion during ANP infusions remained unchanged, an immediate increase of ACTH and cortisol secretion occurred after each infusion period for approximately 2h without changing basal levels and the circadian course of both hormones. Sleep EEG parameters were neither directly affected by ANP infusions nor by the following ANP-induced ACTH and cortisol secretion. The presence of such clear-cut enhancement of the pituitary-adrenal release indicates a rebound effect of ANP on HPA secretory activity and supports the idea that ANP acts as corticotropin-releasing hormone (CRH)-inhibiting factor.

Differential impact of tetratricopeptide repeat proteins on the steroid hormone receptors

BACKGROUND

Tetratricopeptide repeat (TPR) motif containing co-chaperones of the chaperone Hsp90 are considered control modules that govern activity and specificity of this central folding platform. Steroid receptors are paradigm clients of Hsp90. The influence of some TPR proteins on selected receptors has been described, but a comprehensive analysis of the effects of TPR proteins on all steroid receptors has not been accomplished yet.

METHODOLOGY AND PRINCIPAL FINDINGS

We compared the influence of the TPR proteins FK506 binding proteins 51 and 52, protein phosphatase-5, C-terminus of Hsp70 interacting protein, cyclophillin 40, hepatitis-virus-B X-associated protein-2, and tetratricopeptide repeat protein-2 on all six steroid hormone receptors in a homogeneous mammalian cell system. To be able to assess each cofactor's effect on the transcriptional activity of on each steroid receptor we employed transient transfection in a reporter gene assay. In addition, we evaluated the interactions of the TPR proteins with the receptors and components of the Hsp90 chaperone heterocomplex by coimmunoprecipitation. In the functional assays, corticosteroid and progesterone receptors displayed the most sensitive and distinct reaction to the TPR proteins. Androgen receptor's activity was moderately impaired by most cofactors, whereas the Estrogen receptors' activity was impaired by most cofactors only to a minor degree. Second, interaction studies revealed that the strongly receptor-interacting co-chaperones were all among the inhibitory proteins. Intriguingly, the TPR-proteins also differentially co-precipitated the heterochaperone complex components Hsp90, Hsp70, and p23, pointing to differences in their modes of action.

CONCLUSION AND SIGNIFICANCE

The results of this comprehensive study provide important insight into chaperoning of diverse client proteins via the combinatorial action of (co)-chaperones. The differential effects of the TPR proteins on steroid receptors bear on all physiological processes related to steroid hormone activity.