OBJECTIVE:Cardiovascular disease (CVD) and major depressive disorder (MDD) are frequent worldwide and have a high comorbidity rate. Omega-3 fatty acids have been suggested as disease modulators for both CVD and MDD. Therefore, we studied whether polyunsaturated fatty acids and the Omega-3 Index may represent markers for assessment of the cardiovascular risk in somatically healthy patients suffering from MDD.METHOD:We conducted a case-control study from July 2004 to December 2007 in 166 adults (86 inpatients with MDD but without CVD from the Department of Psychiatry and Psychotherapy and 80 age- and sex-matched healthy controls from an outpatient clinic of the Division of Preventive Cardiology, Ludwig Maximilian University of Munich, Germany). Information gathered at baseline included MDD diagnosis according to DSM-IV criteria, depression ratings, conventional cardiovascular risk factors, and fatty acid and interleukin-6 determinations. Fatty acid composition was analyzed according to the HS-Omega-3 Index methodology. During the study, patients received no supplementation with omega-3 fatty acids. The main inclusion criteria were the diagnosis of MDD according to DSM-IV and a 17-item Hamilton Depression Rating Scale (HDRS-17) score of at least 17. Treatment response and remission were defined using the HDRS-17.RESULTS:Several conventional risk factors such as high triglyceride (mean, 152 mg/dL vs 100 mg/dL; P < .001) and fasting glucose (mean, 96 mg/dL vs 87 mg/dL; P = .005) values as well as greater waist circumference (mean, 97 cm vs 87 cm; P = .019) and higher body mass index (calculated as kg/m(2); mean, 26 vs 24; P = .011) were more prevalent in MDD patients in comparison with controls. The Omega-3 Index (mean, 3.9% vs 5.1%; P < .001) and individual omega-3 fatty acids were significantly lower in MDD patients. An Omega-3 Index < 4% was associated with high concentrations of the proinflammatory cytokine interleukin-6 (χ(2) = 7.8, P = .02).CONCLUSIONS:Conventional cardiovascular risk factors, the Omega-3 Index, and interleukin-6 levels indicated an elevated cardiovascular risk profile in MDD patients currently free of CVD. Our results support the employment of strategies to reduce the cardiovascular risk in still cardiovascularly healthy MDD patients by targeting conventional risk factors and the Omega-3 Index.

In the past decades considerable evidence has emerged that so-called neuroactive steroids do not only act as transcriptional factors in the regulation of gene expression but may also alter neuronal excitability through interactions with specific neurotransmitter receptors such as the GABA(A) receptor. In particular, 3α-reduced neuroactive steroids such as allopregnanolone or allotetrahydrodeoxycorticosterone have been shown to act as positive allosteric modulators of the GABA(A) receptor and to play an important role in the pathophysiology of depression and anxiety. During depression, the concentrations of 3α,5α-tetrahydroprogesterone and 3α,5β-tetrahydroprogesterone are decreased, while the levels of 3β,5α-tetrahydroprogesterone, a stereoisomer of 3α,5α-tetrahydroprogesterone, which may act as an antagonist for GABAergic steroids, are increased. Antidepressant drugs such as selective serotonin reuptake inhibitors (SSRIs) or mirtazapine apparently have an impact on key enzymes of neurosteroidogenesis and have been shown to normalize the disequilibrium of neuroactive steroids in depression by increasing 3α-reduced pregnane steroids and decreasing 3β,5α-tetrahydroprogesterone. Moreover, 3α-reduced neuroactive steroids have been demonstrated to possess antidepressant- and anxiolytic-like effects both in animal and human studies for themselves. In addition, the translacator protein (18 kDa) (TSPO), previously called peripheral benzodiazepine receptor, is the key element of the mitochondrial import machinery supplying the substrate cholesterol to the first steroidogenic enzyme (P450scc), which transforms cholesterol into pregnenolone, the precursor of all neurosteroids. TSPO ligands increase neurosteroidogenesis and are a target of novel anxiolytic drugs producing anxiolytic effects without causing the side effects normally associated with conventional benzodiazepines such as sedation or tolerance. This article is part of a Special Issue entitled: Neuroactive Steroids: Focus on Human Brain.

Introduction Cardiovascular disease (CVD) and major depressive disorders (MDD) are frequent diseases worldwide with a high comorbidity rate. Omega-3 fatty acids have been suggested as disease modulators for both CVD and MDD. Objective and aims Therefore, we studied whether polyunsaturated fatty acids and the Omega-3 Index may represent markers for assessment of the cardiovascular risk in physically healthy patients suffering from MDD. Methods Case-control study in 166 adults (86 MDD patients without CVD, 80 matched healthy controls). Baseline examinations included depression ratings, conventional cardiovascular risk factors, fatty acid, and interleukin-6 determinations. Results Several conventional risk factors were more prevalent in MDD patients. The Omega-3 Index and individual omega-3 fatty acids were significantly lower in MDD patients. An Omega-3 Index < 4% was associated with high concentrations of the proinflammatory cytokine IL-6. Conclusion Conventional cardiovascular risk factors, the Omega-3 Index and IL-6 indicated an elevated cardiovascular risk profile in MDD patients currently free of CVD. Our results support the employment of strategies to reduce the cardiovascular risk in yet cardiovascularly healthy MDD patients by targeting conventional risk factors and the Omega-3 Index.

ObjectivesThere is evidence that the antioxidant enzyme glyoxalase-1 (Glx-1) may play a role in anxiety-related behaviour. However, discordant findings between Glx-1 expression and anxiety-related behaviour have been observed in animal models. Because no data are available on the relation between Glx-1 mRNA expression and human anxiety so far, we investigated the expression of Glx-1 mRNA in peripheral red blood cells in relation to cholecystokinin-tetrapeptide (CCK-4) induced anxiety in healthy subjects.MethodsTwenty-three healthy subjects underwent challenge with CCK-4. Glx-1 mRNA expression was assessed by quantitative real-time polymerase chain reaction prior to CCK-4 injection. Baseline anxiety was assessed with the State-Trait-Anxiety-Inventory (STAI) and panic response was measured with the Panic Symptom Scale (PSS).ResultsCCK-4 elicited a marked anxiety response accompanied by a significant increase in heart rate. Glx-1 mRNA expression correlated significantly with severity of CCK-4 induced anxiety. In contrast, Glx-1 activity did not correlate with state or trait anxiety.ConclusionsThe positive correlation between Glx-1 mRNA expression and CCK-4 induced panic severity suggests that Glx-1 is involved into the acute anxiety response to CCK-4. Our preliminary findings support preclinical findings and point towards a role of Glx-1 for human anxiety.

Core symptoms of depression are a combination of psychological and somatic symptoms, often associated with psychomotor and cognitive disturbances. The diagnostic classifications of depression include the concepts of melancholic, endogenous, or severe depression. All subgroups describe severely depressed patients suffering from most of the core symptoms of depression. In addition these patients exhibit the clinical characteristics of a recurrent unipolar or bipolar course, lower placebo response rates, or higher response rates to ECT, to antidepressant treatments with dually or mixed modes of action, or to lithium augmentation. Higher rates of HPA axis hyperactivity and specific EEG patterns may also occur in this patient group. This suggests a broad overlap of patient subgroups within the diagnostic classification of depression. Because the positive diagnosis of the core symptoms of depression may include clinical consequences, it would be useful to integrate all these concepts into the upcoming new versions of the diagnostic systems DSM-V and ICD-11.

INTRODUCTION:There is evidence that a decreased GABAergic tone plays a role in the pathophysiology of panic disorder (PD). Selective GABAergic treatment has been suggested as a new therapeutic strategy in PD. In this pilot-study anxiolytic effects of the GABA reuptake inhibitor tiagabine (TGB) were investigated in PD. METHODS:A total of 19 patients were treated with TGB (n=10) or placebo (n=9) for 4 weeks. PAS, HAM-A, and CGI ratings were administered every week. To further assess specific antipanic activity, panic challenges with CCK-4 were carried out in single subjects. RESULTS:Although there was a significant reduction of clinical rating scores over time, no differences were detected between the groups. However, during challenge experiments TGB treated subjects showed decreased sensitivity to CCK-4. DISCUSSION:Whereas tiagabine did not show beneficial effects on clinical symptoms in PD compared to placebo, results of challenge experiments suggest effects of TGB on sensitivity to experimentally induced panic.

The experimental triggering of panic attacks under controlled conditions offers the possibility to examine the pathophysiological factors which form the base of panic disorders. The application of CCK-4 to release panic attacks is considered to be a safe, valid and reliable model to investigate neurobiological aspects of panic disorders. The aim of the present study was to investigate the brain activity pattern evoked by a CCK-4 induced panic attack using functional MRI and focusing on the putative involvement of the amygdala in the CCK-4 elicited anxiety response.

Unter Kernsymptomen einer Depression versteht man eine Reihe typischer psychischer und somatischer Symptome, die häufig gemeinsam mit psychomotorischen und kognitiven Störungen auftreten. Die aktuelle diagnostische Klassifikation der Depression kennt und beschreibt Subtypen depressiver Episoden wie z. B. melancholische, endogene und schwergradige depressive Episoden. Alle diese Konzepte charakterisieren letztlich schwer depressive Patienten, die neben depressiven Kernsymptomen weitere charakteristische klinische Merkmale aufweisen. Häufig finden sich ein zyklischer Erkrankungsverlauf (uni- oder bipolar) und niedrige Ansprechraten auf eine Behandlung mit Placebo. Nicht selten weisen diese auch höhere Ansprechraten nach einer Elektrokonvulsionstherapie und besseres Ansprechen auf Antidepressiva mit dualem oder gemischtem pharmakodynamischem Wirkmechanismus sowie auf eine Lithiumaugmentation auf. Auch charakteristische neuroendokrinologische Auffälligkeiten wie eine Hyperaktivität der Hypothalamus-Hypophysen-Nebennierenrinden-Achse und spezifische Muster im Elektroenzephalogramm wurden vermehrt beschrieben. In einer vergleichenden Zusammenschau der depressiven Symptomatik von Patienten dieser Subgruppen finden sich relativ große Überschneidungen. Weil sich durch die Diagnose depressiver Kernsymptome klinische Konsequenzen ergeben, könnte eine Integration der dargestellten Konzepte in die anstehenden neuen Versionen von ICD und DSM sinnvoll sein.

Pharmacological magnetic resonance imaging (phMRI) is a method to study effects of psychopharmacological agents on neural activation. Changes of the blood oxygen level dependent (BOLD), the basis of functional MRI (fMRI), are typically obtained at relatively high sampling frequencies. This has more recently been exploited in the field of fMRI by applying independent component analysis (ICA), an explorative data analysis method decomposing activation into distinct neural networks. While already successfully used to investigate resting network and task-induced activity, its use in phMRI is new. Further extension of this method to tensorial probabilistic ICA (tensor PICA) allows to group similar brain activation across the anatomical, temporal, subject or session domain. This approach is useful for pharmacological experiments when no pharmacokinetic model exists. We exemplify this method using data from a placebo-controlled cholecystokinine-4 (CCK-4) injection experiment performed on 16 neuropsychiatrically and medically healthy males (age 25.6 +/- 4.2 years). Tensor PICA identified strong increases in activity in 12 networks. Comparison with results gained from the standard approach (voxelwise regression analysis) revealed good reproduction of areas previously associated with CCK-4 action, such as the anterior cingulate, orbitofrontal cortex, cerebellum, temporolateral, left parietal and insular areas, striatum, and precuneus. Several other components such as the dorsal anterior cingulate and medial prefrontal cortex were identified, suggesting higher sensitivity of the method. Exploration of the time courses of each activated network revealed differences, that might be lost when a fixed time course is modeled, e. g. neuronal responses to an acoustic warning signal prior to injection. Comparison of placebo and CCK-4 runs further showed that a proportion of networks are newly elicited by CCK-4 whereas other components are significantly active in the placebo conditions but further enhanced by CCK-4. In conclusion, group ICA is a promising tool for phMRI studies that allows quantifying and visualizing the modulation of neural networks by pharmacological interventions.

Experimental panic induction with cholecystokinin tetrapeptide (CCK-4) is considered as a suitable model to investigate the pathophysiology of panic attacks. While only a few studies investigated the brain activation patterns following CCK-4, no data are available on the putative involvement of the amygdala in the CCK-4 elicited anxiety response. We studied the functional correlates of CCK-4-induced anxiety in healthy volunteers by means of functional magnetic resonance imaging (fMRI) and region of interest (ROI) analysis of the amygdala. Sixteen healthy volunteers underwent challenge with CCK-4 compared with placebo in a single-blind design. Functional brain activation patterns were determined for the CCK-4-challenge, the placebo response and anticipatory anxiety (AA). CCK-4-induced anxiety was accompanied by a strong and robust activation (random effects analysis, P < 0.00001, uncorrected for multiple testing) in the ventral anterior cingulate cortex (ACC), middle and superior frontal gyrus, precuneus, middle and superior temporal gyrus, occipital lobe, sublobar areas, cerebellum, and brainstem. In contrast, random effects group analysis for placebo and AA using the same level of significance generated no significant results. Using a more liberal level of significance, activations could be observed in some brain regions such as the dorsal part of the ACC during AA (random effects analysis, P < 0.005). Overall functional responses did not differ between panickers and nonpanickers. Only 5 of 11 subjects showed strong amygdala activation. However, ROI analysis pointed towards higher scores in fear items in these subjects. In conclusion, while overall brain activation patterns are not related to the subjective anxiety response to CCK-4, amygdala activation may be involved in the subjective perception of CCK-4-induced fear.

President of the IPEG and of the Scientific Program Committee Gé S.F. Ruigt, Oss (The Netherlands) President of the Local Organizing Committee Rémy Luthringer, Rouffach (France)

Objective: There is overwhelming evidence that activation of the hypothalamic-pituitary-adrenal (HPA) system plays a major role in depression and cardiovascular disease in genetically susceptible individuals. We hypothesized that due to the multiple interactions between the sympathetic and the HPA systems via adrenoceptors, polymorphisms in these genes could have an impact on HPA axis activity in major depression. Methods: Using the dexamethasone/corticotrophin-releasing hormone (DEX/CRH) test, we investigated the association of α2-adrenoceptor (ADRA2A –1291C→G) and the β2-adrenoceptor gene (ADRB2 Arg16Gly) in 189 patients with major depression during the acute state of the disease and after remission. Results: Male ADRA2A –1291G allele homozygotes showed significant pretreatment HPA axis hyperactivity, with increased adrenocorticotropin (ACTH; F = 4.9, d.f. = 2, p = 0.009) and cortisol responses (F = 6.4, d.f. = 2, p = 0.003). In contrast, female ADRB2 Arg/Arg homozygotes had increased pretreatment ACTH (F = 7.17, d.f. = 2, p = 0.001) and cortisol (F = 8.95, d.f. = 2, p = 0.000) levels. Interestingly, in the respective genotypes, the stress hormones remained elevated in the second DEX/CRH test, despite a reduction in depressive symptoms. Conclusions: This study provides evidence that, depending on gender and polymorphisms, there is continuous HPA axis overdrive in a proportion of patients irrespective of the status of depression. Considering the importance of stress hormones for cardiovascular disorders, our data might suggest that these patients are at high risk of comorbidity between depression and cardiovascular disorders.