miR-323a regulates ERBB4 and is involved in depression

Major depressive disorder (MDD) is a complex and debilitating illness whose etiology remains unclear. Small RNA molecules, such as micro RNAs (miRNAs) have been implicated in MDD, where they display differential expression in the brain and the periphery. In this study, we quantified miRNA expression by small RNA sequencing in the anterior cingulate cortex and habenula of individuals with MDD and psychiatrically-healthy controls. Thirty-two miRNAs showed significantly correlated expression between the two regions (False Discovery Rate < 0.05), of which four, miR-204-5p, miR-320b, miR-323a-3p, and miR-331-3p, displayed upregulated expression in MDD. We assessed the expression of predicted target genes of differentially expressed miRNAs in the brain, and found that the expression of erb-b2 receptor tyrosine kinase 4 (ERBB4), a gene encoding a neuregulin receptor, was downregulated in both regions, and was influenced by miR-323a-3p in vitro. Finally, we assessed the effects of manipulating miRNA expression in the mouse ACC on anxiety- and depressive-like behaviors. Mice in which miR-323-3p was overexpressed or knocked-down displayed increased and decreased emotionality, respectively. Additionally, these mice displayed significantly downregulated and upregulated expression of Erbb4, respectively. Overall, our findings indicate the importance of brain miRNAs in the pathology of MDD, and emphasize the involvement of miR-323a-3p and ERBB4 in this phenotype. Future studies further characterizing miR-323a-3p and neuregulin signaling in depression are warranted.

FRI0054 CHANGES IN DEPRESSIVE SYMPTOMS IN RHEUMATOID ARTHRITIS (RA) PATIENTS DURING TOCILIZUMAB (TCZ) THERAPY: THE GERMAN NONINTERVENTIONAL ARATA STUDY

Background:

Depression is a common comorbidity in patients with RA and influences perception of disease activity and quality of life. We have previously reported that mean depression scores improved during TCZ therapy in conjunction with reductions in disease activity.1

Objectives:

To evaluate individual changes in depressive symptoms over 52 weeks in RA patients initiating treatment with TCZ.

Methods:

We analyzed data from a large German multicenter observational study of patients with active RA who initiated TCZ therapy during routine clinical care (ML29087 ARATA study;NCT02251860). The Beck Depression Inventory-II (BDI-II), a self-report questionnaire for depression screening that has been validated in RA, was used to assess symptoms of depression. Patients were classified by baseline BDI-II scores into depression categories of no (BDI-II<14), mild (BDI-II 14-19), moderate (BDI-II 20-28), and severe depression (BDI-II≥29).2Individual changes in BDI-II scores between baseline and week 52 were assessed. Erythrocyte sedimentation rate was used as the acute phase reactant in Disease Activity Score-28 joints (DAS28) assessments.

Results:

Of 1155 patients enrolled from 108 clinical centers in Germany between May 2014 and July 2018, 474 completed the BDI-II at baseline (BDI-II cohort); baseline characteristics were similar to those of patients who did not complete the BDI-II. Approximately half of patients in the BDI-II cohort had BDI-II scores indicating no depression (248; 52.3%); the remaining patients had mild (87; 18.4%), moderate (84; 17.7%), or severe (55; 11.6%) depression. The mean (SD) baseline characteristics of the BDI-II cohort were 55.5 (12.5) yrs of age, 75.7% female, 10.6 (9.2) yrs RA duration, 4.9 (1.2) DAS28, and 24.3 (10.2) Clinical Disease Activity Index (CDAI). Baseline DAS28 and CDAI scores were similar among different depression subgroups, but patients with severe depression were more likely to be female (87.3% vs 70.6% for no depression) and had higher levels of anxiety, suicidal ideation, fatigue, pain, and sleep disturbance than patients with no or milder depression.

A total of 229 of the 474 patients (48.3%) in the BDI-II cohort completed the BDI-II at both baseline and week 52. At 52 weeks, the depression category of approximately half of patients with depressive symptoms at baseline changed to a lower level or no depression (Figure 1). Moderate to large improvements in BDI-II from baseline (>10 points) were reported by 33.3% to 38.5% of patients with baseline depressive symptoms (Figure 2).

Conclusion:

At 52 weeks after initiating TCZ, the depressive disease burden was reduced. Future analyses with a representative patient cohort will be aimed at exploring whether improvements in depression occur independent of reductions in disease activity.

References:

[1]Behrens F et al.Arthritis Rheumatol2019;71(suppl 10):abstr1414.

[2]Smarr KL, Keefer AL.Arthritis Care Res2011;63(S11):S454-66.

Acknowledgments:

This study was sponsored by Chugai Pharma Germany GmbH and Roche Pharma AG. Sharon L. Cross and Kirsten Dahm provided medical writing services supported by Chugai. Statistical analyses were provided by Roche Pharma AG.

Disclosure of Interests:

Frank Behrens Grant/research support from: Pfizer, Janssen, Chugai, Celgene, Lilly and Roche, Consultant of: Pfizer, AbbVie, Sanofi, Lilly, Novartis, Genzyme, Boehringer, Janssen, MSD, Celgene, Roche and Chugai, Gerd Rüdiger Burmester Consultant of: AbbVie Inc, Eli Lilly, Gilead, Janssen, Merck, Roche, Pfizer, and UCB Pharma, Speakers bureau: AbbVie Inc, Eli Lilly, Gilead, Janssen, Merck, Roche, Pfizer, and UCB Pharma, Martin Feuchtenberger Consultant of: Abbvie, BMS, Chugai, Sanofi, Speakers bureau: Abbvie, BMS, Celgene, Chugai, Jansen-Cilag, Lilly, Pfizer, Roche, Sanofi, UCB, Herbert Kellner: None declared, Cornelia Kühne Grant/research support from: Novartis, Amgen, Roche/Chugai, Pfizer, Celgene, AbbVie, Sanofi, Anke Liebhaber: None declared, Maren Sieburg: None declared, Siegfried Wassenberg: None declared, Christina Luig Employee of: Roche Pharma AG, Michael W. Hofmann Employee of: Chugai Pharma Germany GmbH, Christopher Amberger Grant/research support from: Chugai Pharma Germany GmbH, Consultant of: Chugai Pharma Germany GmbH

OP0020 IMPACT OF BDMARDS WITH DIFFERENT MODES OF ACTION ON FATIGUE IN RA PATIENTS

Background:

Fatigue is an important patient-reported outcome. It has been reported to be potentially targetable by DMARDs with specific modes of action, particularly IL-6 inhibition [1].

Objectives:

To assess to which extent patients on DMARDs with different modes of action reach fatigue levels of 2 or less on a 0 (no fatigue) to 10 (high fatigue) scale after 6 months of treatment.

Methods:

The German register RABBIT is a prospective longitudinally followed cohort of RA patients enrolled with a new start of a DMARD after at least one csDMARD failure. This analysis comprises bionaive patients who were enrolled with start of a b/tsDMARD between 01/2009 and 04/2019, who had at least 1 follow-up, did not switch during the first 3 months and afterwards only within the same substance, and presented fatigue levels of > 2 at baseline.

Poisson regression models with a robust error variance were used to calculate risk ratios (RRs) for reaching fatigue values ≤ 2, for all DMARD modes of action. Propensity score weighting was used to adjust for confounding by indication. Multiple imputation of missing values was performed.

Results:

Baseline fatigue levels were 5.1 overall and 6.1 among patients with a fatigue level of > 2 points on average. They were comparable among different DMARD modes of action. csDMARD patients had lower values than others regarding disease duration, disease activity, or joint erosions (Table 1).

Table 1.

Patient characteristics for different DMARD modes of action

ParametercsDMARDsTNFiRTXABAIL-6JAKiN23762772115166357110Fatigue at baseline5.9 (2)6.1 (2)5.9 (2)5.9 (1.9)6.1 (2)6.3 (1.9)Age [years]58.5 (12.7)56.3 (12.4)62.7 (10.9)59.7 (12.6)57.9 (12.5)61.5 (11.5)Female sex1809 (76.1)2060 (74.3)82 (71.2)118 (71)272 (76.3)79 (70.1)Disease duration [years]6.2 (7.2)8.7 (8.1)10.8 (9.7)9.8 (9.2)7.9 (7.6)8.5 (10)Joint erosions634 (28.4)1358 (50.5)62 (56.8)91 (55.4)158 (46.4)45 (41.3)Prior csDMARD therapies1.3 (0.6)2.3 (1)2.5 (1.1)2.2 (1)2.2 (0.9)1.8 (0.8)DAS28-ESR4.6 (1.2)5 (1.2)5.3 (1.3)5.3 (1.2)5.2 (1.3)4.9 (1.3)% of full physical capacity67.4 (21.6)64.6 (22)57 (23.5)59.5 (21.3)63.8 (20.9)61.6 (23)Glucocorticoid therapy (last 6 months)1161 (48.9)1747 (63)76 (66.4)93 (56)198 (55.5)42 (38.1)Fibromyalgia73 (3.1)111 (4)6 (5.2)7 (4.2)11 (3.1)1 (0.9)Depression180 (7.6)218 (7.9)10 (8.7)14 (8.4)26 (7.3)16 (14.6)Ever smoker1252 (52.7)1497 (54)68 (59)84 (50.7)200 (56)59 (53.5)

Results are presented as mean ± SD or number (percentage). Absolute numbers may be rounded due to multiple imputation.

The RR of IL-6 inhibitors for achieving a fatigue level of ≤ 2 was 1.34 (95% CI: 1.09 – 1.64) compared to csDMARDs. Among other factors, current smoking, prevalent fibromyalgia and depression had a negative impact on achieving a low fatigue level (Table 2).

Table 2.

Risk ratios for achieving fatigue levels ≤2

Parameter (at baseline)RR95% confidence intervalFatigue (1 point higher)0.83(0.80;0.86)TNF inhibitor (vs. csDMARDs)1.11(0.99;1.24)Rituximab (vs. csDMARDs)1.10(0.71;1.68)Abatacept (vs. csDMARDs)1.13(0.82;1.54)IL-6 inhibitor (vs. csDMARDs)1.34(1.09;1.64)JAK inhibitor (vs. csDMARDs)1.19(0.81;1.75)Age (5 years more)0.97(0.95;0.99)Female sex0.83(0.74;0.92)Patient global health (1 point higher)0.97(0.94;0.997)Joint erosions1.19(1.07;1.32)Current smoking0.86(0.76;0.98)Former smoking0.92(0.82;1.04)Fibromyalgia0.56(0.35;0.90)Depression0.75(0.59;0.95)

Conclusion:

Treatment with IL-6 inhibitors significantly increases the chance of reaching low fatigue levels within half a year in RA patients, while current smoking reduces it.

References:

[1]Choy E.H.S. and Calabrese L. H Rheumatology 2018;57:1885-95.

Acknowledgments:

RABBIT is supported by a joint, unconditional grant from AbbVie, Amgen, BMS, Fresenius Kabi, Hexal, Lilly, MSD, Mylan, Pfizer, Roche, Samsung Bioepis, Sanofi-Aventis, and UCB.

Disclosure of Interests:

Martin Schaefer: None declared, Peter Herzer Speakers bureau: AbbVie, Novartis, Sanofi, Janssen, Cornelia Kühne Grant/research support from: Novartis, Amgen, Roche/Chugai, Pfizer, Celgene, AbbVie, Sanofi, Herbert Kellner Grant/research support from: Biogen, Consultant of: Biogen, Speakers bureau: Biogen, Angela Zink Speakers bureau: AbbVie, Amgen, BMS, Gilead, Hexal, Janssen, Lilly, MSD, Pfizer, Roche, Sanofi Aventis, UCB, Anja Strangfeld Speakers bureau: AbbVie, BMS, Pfizer, Roche, Sanofi-Aventis

Deletion of CRH From GABAergic Forebrain Neurons Promotes Stress Resilience and Dampens Stress-Induced Changes in Neuronal Activity

Dysregulation of the corticotropin-releasing hormone (CRH) system has been implicated in stress-related psychopathologies such as depression and anxiety. Although most studies have linked CRH/CRH receptor 1 signaling to aversive, stress-like behavior, recent work has revealed a crucial role for distinct CRH circuits in maintaining positive emotional valence and appetitive responses under baseline conditions. Here we addressed whether deletion of CRH, specifically from GABAergic forebrain neurons (Crh ^CKO-GABA mice) differentially affects general behavior under baseline and chronic stress conditions. Expression mapping in Crh ^{CK O-GABA} mice revealed absence of Crh in GABAergic neurons of the cortex and limbic regions including the hippocampus, central nucleus of the amygdala and the bed nucleus of the stria terminals, but not in the paraventricular nucleus of hypothalamus. Consequently, conditional CRH knockout animals exhibited no alterations in circadian and stress-induced corticosterone release compared to controls. Under baseline conditions, absence of Crh from forebrain GABAergic neurons resulted in social interaction deficits but had no effect on other behavioral measures including locomotion, anxiety, immobility in the forced swim test, acoustic startle response and fear conditioning. Interestingly, following exposure to chronic social defeat stress, Crh ^CKO-GABA mice displayed a resilient phenotype, which was accompanied by a dampened, stress-induced expression of immediate early genes c-fos and zif268 in several brain regions. Collectively our data reveals the requirement of GABAergic CRH circuits in maintaining appropriate social behavior in naïve animals and further supports the ability of CRH to promote divergent behavioral states under baseline and severe stress conditions.

Deciphering the Contributions of CRH Receptors in the Brain and Pituitary to Stress-Induced Inhibition of the Reproductive Axis

Based on pharmacological studies, corticotropin-releasing hormone (CRH) and its receptors play a leading role in the inhibition of the hypothalamic–pituitary–gonadal (HPG) axis during acute stress. To further study the effects of CRH receptor signaling on the HPG axis, we generated and/or employed male mice lacking CRH receptor type 1 (CRHR1) or type 2 (CRHR2) in gonadotropin-releasing hormone neurons, GABAergic neurons, or in all central neurons and glia. The deletion of CRHRs revealed a preserved decrease of plasma luteinizing hormone (LH) in response to either psychophysical or immunological stress. However, under basal conditions, central infusion of CRH into mice lacking CRHR1 in all central neurons and glia, or application of CRH to pituitary cultures from mice lacking CRHR2, failed to suppress LH release, unlike in controls. Our results, taken together with those of the earlier pharmacological studies, suggest that inhibition of the male HPG axis during acute stress is mediated by other factors along with CRH, and that CRH suppresses the HPG axis at the central and pituitary levels via CRHR1 and CRHR2, respectively.

Chronic CRH depletion from GABAergic, long-range projection neurons in the extended amygdala reduces dopamine release and increases anxiety

The interplay between corticotropin-releasing hormone (CRH) and the dopaminergic system has predominantly been studied in addiction and reward, while CRH-dopamine interactions in anxiety are scarcely understood. We describe a new population of CRH-expressing, GABAergic, long-range-projecting neurons in the extended amygdala that innervate the ventral tegmental area and alter anxiety following chronic CRH depletion. These neurons are part of a distinct CRH circuit that acts anxiolytically by positively modulating dopamine release.

CRFR1 in AgRP Neurons Modulates Sympathetic Nervous System Activity to Adapt to Cold Stress and Fasting

Signaling by the corticotropin-releasing factor receptor type 1 (CRFR1) plays an important role in mediating the autonomic response to stressful challenges. Multiple hypothalamic nuclei regulate sympathetic outflow. Although CRFR1 is highly expressed in the arcuate nucleus (Arc) of the hypothalamus, the identity of these neurons and the role of CRFR1 here are presently unknown. Our studies show that nearly half of Arc-CRFR1 neurons coexpress agouti-related peptide (AgRP), half of which originate from POMC precursors. Arc-CRFR1 neurons are innervated by CRF neurons in the hypothalamic paraventricular nucleus, and CRF application decreases AgRP(+)CRFR1(+) neurons' excitability. Despite similar anatomy in both sexes, only female mice selectively lacking CRFR1 in AgRP neurons showed a maladaptive thermogenic response to cold and reduced hepatic glucose production during fasting. Thus, CRFR1, in a subset of AgRP neurons, plays a regulatory role that enables appropriate sympathetic nervous system activation and consequently protects the organism from hypothermia and hypoglycemia.

Fluoxetine treatment prevents the inflammatory response in a mouse model of posttraumatic stress disorder

Despite intense research efforts the molecular mechanisms affecting stress-vulnerable brain regions in posttraumatic stress disorder (PTSD) remain elusive. In the current study we have applied global transcriptomic profiling to a PTSD mouse model induced by foot shock fear conditioning. We compared the transcriptomes of prelimbic cortex, anterior cingulate cortex (ACC), basolateral amygdala, central nucleus of amygdala, nucleus accumbens (NAc) and CA1 of the dorsal hippocampus between shocked and non-shocked (control) mice, with and without fluoxetine treatment by RNA sequencing. Differentially expressed (DE) genes were identified and clustered for in silico pathway analysis. Findings in relevant brain regions were further validated with immunohistochemistry. DE genes belonging to 11 clusters were identified including increased inflammatory response in ACC in shocked mice. In line with this finding, we noted higher microglial activation in ACC of shocked mice. Chronic fluoxetine treatment initiated in the aftermath of the trauma prevented inflammatory gene expression alterations in ACC and ameliorated PTSD-like symptoms, implying an important role of the immune response in PTSD pathobiology. Our results provide novel insights into molecular mechanisms affected in PTSD and suggest therapeutic applications with anti-inflammatory agents.

Synthesis, Photophysical, and Biological Evaluation of Sulfated Polyglycerol Dendronized Perylenebisimides (PBIs)--A Promising Platform for Anti-Inflammatory Theranostic Agents?

A set of four water-soluble perylene bisimides (PBI) based on sulfated polyglycerol (PGS) dendrons were developed, their photophysical properties determined via UV/vis and fluorescence spectroscopy, and their performance as possible anti-inflammatory agents evaluated via biological in vitro studies. It could be shown that in contrast to charge neutral PG-PBIs the introduction of the additional electrostatic repulsion forces leads to a decrease in the dendron generation necessary for aggregation suppression, allowing the preparation of PBIs with fluorescence quantum yields of >95% with a considerable decreased synthetic effort. Furthermore, the values determined for L-selectin binding down to the nanomolar range, their limited impact on blood coagulation, and their minor activation of the complement system renders these systems ideal for anti-inflammatory purposes.

[Implantable cardioverter-defibrillator at the end of life]

Brady- and tachyarrhythmias at the end of life are common observations. Implantable cardioverter-defibrillators answer with antibrady and antitachycardia pacing, which will not be associated with any complaints of the dying patient. In contrast, defibrillation and cardioversion shocks are extremely painful. Therefore shocks should be inactivated at the end of life. Family doctors, internists, emergency physicians and paramedics are unable to inactivate shocks. Deactivation of shocks at the end of life is not comparable to euthanasia or assisted suicide, but allow the patient to die at the end of an uncurable endstage disease. Deactivation of shocks should be discussed with the patient before initial implantation of the devices. The precise moment of the inactivation at the end of life should be discussed with patients and relatives. There is no common recommendation for the time schedule of this decision; therefore it should be based on the individual situation of the patient. Emergency health care physicians need magnets and sufficient information to inactivate defibrillators. The wishes of the patient have priority in the decision process and should be written in the patient's advance directive, which must be available in the final situation. However the physician must not necessarily follow every wish of the patient. As long as the laws in the European Union are not uniform, German recommendations are needed.

Development of a novel IGRA assay to test T cell responsiveness to HBV antigens in whole blood of chronic Hepatitis B patients

BACKGROUND

Interferon gamma release assays (IGRA) have been developed to support easy and fast diagnosis of diseases like tuberculosis, and CMV in transplant patients. IGRAs focus on cellular immunity especially memory T cells and thus also allow rapid screening prior to complex flow cytometric testing. Here, we describe a novel, sensitive whole blood based cytokine release assay capable of assessing T cell responsiveness to HBV antigens in Hepatitis B patients and assessing hepatitis B vaccination status in healthy individuals.

METHODS

Seventy two chronic Hepatitis B patients (CHB), 8 acute hepatitis B patients (AHB) and 80 healthy controls (HC) were tested by ELISA for IFNγ- and IL2-secretion in whole blood after challenge with synthetic peptide libraries of hepatitis B core antigen (HBcAg) or hepatitis B surface antigen (HBsAg).

RESULTS

The developed IGRA test reliably differentiated between Hepatitis B patients, vaccinees and unvaccinated healthy controls. Treatment naïve and treated CHB patients showed a weaker IFNγ response to HBcAg (16 ± 5 and 35 ± 28 pg/ml, respectively) compared to the AHB group (82 ± 39 pg/ml), whereas HC remained unresponsive (6 ± 1 pg/ml). IL2 levels after HBcAg challenge were also higher in the AHB group compared to naive and treated CHB as well as HC (47 ± 21 vs. 12 ± 3, 15 ± 10 and 12 ± 9 pg/ml, respectively). HBsAg stimulation led to increased IFNγ and IL2 levels in the AHB group (33 ± 12 and 22 ± 12 pg/ml) and even higher levels in HC due to a high hepatitis B vaccination rate (41 ± 10 and 167 ± 58 pg/ml). Naive and treated CHB patients developed no or only weaker IFNγ or IL2 responses to HBsAg (5 ± 2 and 12 ± 7 pg/ml, for naive CHB, 12 ± 10 and 18 ± 15 pg/ml, for treated CHB). For HC, IL2 release after HBsAg stimulation depicted hepatitis B vaccination status with a diagnostic sensitivity and specificity of 85 % and 90 %.

CONCLUSION

Our novel whole blood based cytokine release assay constitutes an easy and robust tool for screening HBV specific cellular immunity as alternative to flow cytometry or ELISPOT assays.

Optogenetic evocation of field inhibitory postsynaptic potentials in hippocampal slices: a simple and reliable approach for studying pharmacological effects on GABAA and GABAB receptor-mediated neurotransmission

The GABAergic system is the main source of inhibition in the mammalian brain. Consequently, much effort is still made to develop new modulators of GABAergic synaptic transmission. In contrast to glutamatergic postsynaptic potentials (PSPs), accurate monitoring of GABA receptor-mediated PSPs (GABAR-PSPs) and their pharmacological modulation in brain tissue invariably requires the use of intracellular recording techniques. However, these techniques are expensive, time- and labor-consuming, and, in case of the frequently employed whole-cell patch-clamp configuration, impact on intracellular ion concentrations, signaling cascades, and pH buffering systems. Here, we describe a novel approach to circumvent these drawbacks. In particular, we demonstrate in mouse hippocampal slices that selective optogenetic activation of interneurons leads to prominent field inhibitory GABAAR- and GABABR-PSPs in area CA1 which are easily and reliably detectable by a single extracellular recording electrode. The field PSPs exhibit typical temporal and pharmacological characteristics, display pronounced paired-pulse depression, and remain stable over many consecutive evocations. Additionally validating the methodological value of this approach, we further show that the neuroactive steroid 5α-THDOC (5 μM) shifts the inhibitory GABAAR-PSPs towards excitatory ones.

Deducing corticotropin-releasing hormone receptor type 1 signaling networks from gene expression data by usage of genetic algorithms and graphical Gaussian models

BACKGROUND

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is a hallmark of complex and multifactorial psychiatric diseases such as anxiety and mood disorders. About 50-60% of patients with major depression show HPA axis dysfunction, i.e. hyperactivity and impaired negative feedback regulation. The neuropeptide corticotropin-releasing hormone (CRH) and its receptor type 1 (CRHR1) are key regulators of this neuroendocrine stress axis. Therefore, we analyzed CRH/CRHR1-dependent gene expression data obtained from the pituitary corticotrope cell line AtT-20, a well-established in vitro model for CRHR1-mediated signal transduction. To extract significantly regulated genes from a genome-wide microarray data set and to deduce underlying CRHR1-dependent signaling networks, we combined supervised and unsupervised algorithms.

RESULTS

We present an efficient variable selection strategy by consecutively applying univariate as well as multivariate methods followed by graphical models. First, feature preselection was used to exclude genes not differentially regulated over time from the dataset. For multivariate variable selection a maximum likelihood (MLHD) discriminant function within GALGO, an R package based on a genetic algorithm (GA), was chosen. The topmost genes representing major nodes in the expression network were ranked to find highly separating candidate genes. By using groups of five genes (chromosome size) in the discriminant function and repeating the genetic algorithm separately four times we found eleven genes occurring at least in three of the top ranked result lists of the four repetitions. In addition, we compared the results of GA/MLHD with the alternative optimization algorithms greedy selection and simulated annealing as well as with the state-of-the-art method random forest. In every case we obtained a clear overlap of the selected genes independently confirming the results of MLHD in combination with a genetic algorithm. With two unsupervised algorithms, principal component analysis and graphical Gaussian models, putative interactions of the candidate genes were determined and reconstructed by literature mining. Differential regulation of six candidate genes was validated by qRT-PCR.

CONCLUSIONS

The combination of supervised and unsupervised algorithms in this study allowed extracting a small subset of meaningful candidate genes from the genome-wide expression data set. Thereby, variable selection using different optimization algorithms based on linear classifiers as well as the nonlinear random forest method resulted in congruent candidate genes. The calculated interacting network connecting these new target genes was bioinformatically mapped to known CRHR1-dependent signaling pathways. Additionally, the differential expression of the identified target genes was confirmed experimentally.

[Central corneal thickness measurement with online optical coherence pachymetry and ultrasound pachymetry in 513 consecutive eyes]

BACKGROUND

The aim of this study was to assess the reliability of online optical coherence pachymetry (OCP) integrated into the Technolas excimer platform by comparing the intraoperative OCP corneal thickness measurement with the preoperative standard ultrasound pachymetry (USP).

PATIENTS/MATERIALS AND METHODS

The mean central corneal thickness of 513 consecutive eyes was measured using OCP and USP. Immediately before starting the LASIK procedure, three OCP measurements of the central cornea (OCPonline, Heidelberg Engineering GmbH, Germany) were done under the microscope of the Excimer laser (Technolas, Bausch and Lomb, Rochester, NY). The mean value of 10 central USP measurements (Sp-3000, Tomey, Japan) was obtained during the preoperative assessment of the patients. The comparison of the two methods was done using Pearson regression analysis and the Bland- Altman method.

RESULTS

Mean central corneal thickness of the OCP and the USP were 523.1 +/- 30.5 microm and 561.2 +/- 32.7 microm, respectively. The correlation coefficient was r = 0.891 for the two methods. The mean difference between USP and OCP was 37.9 +/- 14.8 microm.

CONCLUSIONS

The intraoperative OCP gives 7% smaller measurements compared with the preoperative USP.

Profiling of behavioral changes and hippocampal gene expression in mice chronically treated with the SSRI paroxetine

INTRODUCTION

Monoamine-based antidepressants inhibit neurotransmitter reuptake within short time. However, it commonly takes several weeks until clinical symptoms start to resolve--indicating the involvement of effects distant from reuptake inhibition.

OBJECTIVE

To unravel other mechanisms involved in drug action, a "reverse" pharmacological approach was applied to determine antidepressant-induced alterations of hippocampal gene expression.

MATERIALS AND METHODS

The behavioral response to long-term paroxetine administration of male DBA/2Ola mice was assessed by the forced swim test (FST), the modified hole board (mHB), and the dark/light box. Hippocampi of test-naive mice were dissected, and changes in gene expression by paroxetine treatment were investigated by means of microarray technology.

RESULTS AND DISCUSSION

Robust effects of paroxetine on passive stress-coping behavior in the FST were observed. Furthermore, anxiolytic properties of long-term antidepressant treatment could be identified in DBA mice in both, the mHB and dark/light box. Analysis of microarray results revealed a list of 60 genes differentially regulated by chronic paroxetine treatment. Preproenkephalin 1 and inhibin beta-A showed the highest level of transcriptional change. Furthermore, a number of candidates involved in neuroplasticity/neurogenesis emerged (e.g., Bdnf, Gfap, Vim, Sox11, Egr1, Stat3). Seven selected candidates were confirmed by in situ hybridization. Additional immunofluorescence colocalization studies of GFAP and vimentin showed more positive cells to be detected in long-term paroxetine-treated DBA mice.

CONCLUSION

Candidate genes identified in the current study using a mouse strain validated for its responsiveness to long-term paroxetine treatment add, in our opinion, to unraveling the mechanism of action of paroxetine as a representative for SSRIs.

Expression profiling identifies the CRH/CRH-R1 system as a modulator of neurovascular gene activity

Corticotropin-releasing hormone receptor type 1 (CRH-R1)-deficient mice display reduced anxiety-like behavior, a chronic corticosterone deficit, and an impaired neuroendocrine stress response caused by disruption of the hypothalamic-pituitary-adrenocortical (HPA) axis. The molecular substrates and pathways of CRH/CRH-R1-dependent signaling mechanisms underlying the behavioral phenotype as well as the consequences of lifelong glucocorticoid deficit remain largely obscure. To dissect involved neuronal circuitries, we performed comparative expression profiling of brains of CRH-R1 mutant and wild-type mice using our custom made MPIP (Max Planck Institute of Psychiatry) 17k cDNA microarray. Microarray analysis yielded 107 genes showing altered expression levels when comparing CRH-R1 knockout mice with wild-type littermates. A significant proportion of differentially expressed genes was related to control of HPA and hypothalamic-pituitary-thyroid (HPT) axes reflecting not only the disturbance of the HPA axis in CRH-R1 mutant mice but also the interplay of both neuroendocrine systems. The spatial analysis of regulated genes revealed a prevalence for genes expressed in the cerebral microvasculature. This phenotype was confirmed by the successful cross-validation of regulated genes in CRH overexpressing mice. Analysis of the cerebral vasculature of CRH-R1 mutant and CRH overexpressing mice revealed alterations of functional rather than structural properties. A direct role of the CRH/CRH-R1 system was supported by demonstrating Crhr1 expression in the adult murine cerebral vasculature. In conclusion, these data suggest a novel, previously unknown role of the CRH/CRH-R1 system in modulating neurovascular gene expression and function.

Zyklorotation des Auges bei wellenfrontgeführter LASIK mit statischem Iriserkennungstracker

PURPOSE

Centration of the ablation zone decisively influences the result of wavefront-guided LASIK. Cyclorotation of the eye occurs as the patient changes from the sitting position during aberrometry to the supine position during laser surgery and may lead to induction of lower and higher order aberrations.

METHODS

Twenty patients (40 eyes) underwent wavefront-guided LASIK (B&L 217z 100 excimer laser) with a static eyetracker driven by iris recognition (mean preoperative SE: -4.72+/-1.45 D; range: -1.63 to -7.00 D). The iris patterns of the patients' eyes were memorized during aberrometry and after flap creation.

RESULTS

The mean absolute value of the measured cyclorotation was -1.5+/-4.2 degrees (range: -11.0 to 6.9 degrees ). The mean cyclorotation was 3.5+/-2.7 masculine (range: 0.1 to 11.0 degrees ). In 65% of all eyes cyclorotation was >2 masculine.

CONCLUSIONS

A static eyetracker driven by iris recognition demonstrated that cyclorotation of up to 11 degrees may occur in myopic and myopic astigmatic eyes when changing from a sitting to a supine position. Use of static eyetrackers with iris recognition may provide a more precise positioning of the ablation profile as they detect and compensate cyclorotation.

Wellenfrontanalyse zur Diagnose des subklinischen Keratokonus

BACKGROUND

The entity of subclinical keratoconus (SKC) has not been defined sufficiently yet. The aim of the study was to describe ocular wavefront aberrations of clinically inconspicuous fellow eyes in patients with early keratoconus (KC) as a model of SKC and to assess the feasibility of higher-order wavefront analysis to discriminate eyes with SKC from normal eyes.

METHODS

This prospective study included eight clinically inconspicuous fellow eyes of eight patients with newly detected KC in the contralateral eye and a paracentral inferior-superior difference (PISD) <1.4 D. In total, 15 eyes of 12 patients with newly diagnosed KC and a PISD >1.4 D were included as positive controls and 71 healthy eyes of 40 patients served as negative controls. The wavefront error was measured in all eyes with a Hartmann-Shack sensor. Discriminant analysis was performed with input from ocular HOA data and PISD. Receiver operating characteristic (ROC) curves were plotted for PISD, single Zernike coefficients, and for the output values of the discriminant functions to investigate their usefulness for discrimination between SKC eyes, early KC eyes, and healthy controls.

RESULTS

There were significant differences between inconspicuous fellow eyes (group 2) and controls (group 3) for PISD, for the coefficients Z3(-3), Z3(-1), Z4(0) and Z5(-1), and for the output values of the discriminant functions. The latter discriminated between groups 2 and 3 with maximum sensitivity and specificity (A(z) ROC=1), whereas discriminative ability was considerably lower for single Zernike coefficients.

CONCLUSION

Single Zernike coefficients did not appear to be useful for the detection of SKC. Using discriminant analysis, from PISD and higher-order Zernike coefficients a metric with very high discriminative ability between normal and SKC eyes could be constructed.

Soluble tumour necrosis factor receptor treatment does not affect raised transforming growth factor beta levels in rheumatoid arthritis

OBJECTIVE

To further elucidate the immunomodulating effects of anti-tumour necrosis factor alpha treatment in rheumatoid arthritis (RA) by studying changes in plasma levels of transforming growth factor beta (TGFbeta) in patients with RA undergoing etanercept treatment.

METHODS

Plasma levels of TGFbeta1 and TGFbeta2 were determined in 26 patients with RA during six months of etanercept treatment and compared with disease activity and laboratory parameters, including matrix metalloproteinase-3 (MMP-3) and interleukin 6 (IL6).

RESULTS

Before treatment all patients had raised TGFbeta1, IL6, and MMP-3 levels. In the course of treatment IL6 and MMP-3 levels decreased significantly, accompanied by a drop in serological markers (C reactive protein and erythrocyte sedimentation rate) and clinical disease activity (visual analogue scale and Thompson joint score). By contrast, high levels of latent TGFbeta1 were present in all specimens over the entire six months. TGFbeta2 levels did not change during treatment.

CONCLUSION

Etanercept treatment induces subtle changes in the cytokine network. Although the proinflammatory cytokine IL6 is down regulated, the persistence of high TGFbeta plasma levels indicates the existence of as yet unknown mechanisms for TGFbeta overexpression in RA. This may predispose to severe infections and can cause an altered tumour defence.

The HPV-16 E7 oncoprotein binds Skip and suppresses its transcriptional activity

E7 is the major transforming protein of human papillomavirus (HPV), which is implicated in the development of cervical cancer. The transforming activity of E7 has been attributed in part to its interaction with the retinoblastoma (Rb) tumour suppressor; however, the Rb interaction alone is not sufficient for transformation by E7. In a screen for cellular targets of HPV E7, we identified the Ski interacting protein, Skip, as a new interacting partner of E7. We show that HPV-16 E7 associates with Skip via sequences in its carboxy terminal region, and the evolutionarily conserved proline rich sequences (PRS) of the SNW domain of Skip. E7 functionally targets Skip in vivo and inhibits its transcriptional activation activity. Two transformation defective mutants of E7 were identified that failed both to bind Skip and to inhibit its transcriptional activity. These results suggest that inhibition of Skip function may contribute to cell transformation by HPV-16 E7.

Regulation of the human papillomavirus oncoproteins by differential phosphorylation

Human papillomaviruses (HPVs) are intimately associated with the development of cervical cancer. The virus encodes two oncoproteins, E6 and E7, that are primarily responsible for inducing malignant transformation. The last few years have seen significant progress in elucidating the mechanisms by which these two viral proteins bring about cell transformation. Both proteins interact with a large number of cellular targets, many of which are involved in regulating diverse functions such as cell cycle regulation, transcription, differentiation and apoptosis. However both E6 and E7 are normally present at low levels within the virally infected cell, and how all these interactions are achieved and regulated has, until recently, been unclear. We have found that both E6 and E7 are subject to differential phosphorylation, the net results of which regulate their abilities to interact with some of their respective target proteins. In the case of E6, phosphorylation by Protein Kinase A (PKA) negatively regulates its ability to interact with the Discs Large (Dlg) tumour suppressor. In the case of E7, phosphorylation by Casein Kinase II (CKII) significantly increases its ability to interact with the TATA Box Binding Protein (TBP). Further, CKII regulation of E7 appears to vary during the cell cycle, therefore this provides a means of specifically targeting E7 to a given substrate at a given point within the cell cycle. This differential regulation of E6 and E7 by phosphorylation thus provides specificity to a diverse set of protein-protein interactions.

Ski interacts with the evolutionarily conserved SNW domain of Skip

Ski interacting protein (Skip) has been found to bind to the highly conserved region of Ski, which is required for its transforming activity. Ski is a unique oncoprotein that is involved in inducing both transformation and differentiation. At the molecular level, Ski has been shown to exhibit either co-activator or co-repressor activity depending on the cellular and promoter context. We were interested in further elucidating the biological implications of the Ski-Skip interaction. Here we have identified the SNW domain of Skip as the interaction region for Ski. This domain of Skip is highly conserved in all the Skip homologues identified from different species. Using a series of reporter plasmids, we show that Skip is a potent transcriptional activator of many different promoters, the activity of which was also mapped to the conserved core SNW domain of the protein. Addition of excess Ski further augmented the transcriptional activities of Skip, suggesting that one of the ways in which Ski brings about transformation is by binding and cooperating with the SNW domain of Skip in transcriptional activation.

Differential regulation of human papillomavirus E6 by protein kinase A: conditional degradation of human discs large protein by oncogenic E6

The protein Kinase A (PKA) pathway was found to selectively regulate the function of oncogenic but not non-oncogenic E6 proteins. High risk E6 proteins are phosphorylated at their Dlg/PDZ binding motif at the C-terminus by a PKA like activity. This PKA and PDZ binding module is found only for human PV, is strictly conserved in all the transforming HPVs and is absent in all the low risk HPV types. We present evidence of a conditional regulation of E6 induced degradation of Dlg. HPV18E6 positive but not HPV negative keratinocytes exhibit increased Dlg steady state levels under conditions of high PKA activity, with a concomitant increase in the presence of Dlg at tight junctions. In vitro binding experiments show that E6 phosphorylation by PKA reduces its binding to Dlg and molecular modelling can explain this observation in a structural context. E6 dependent degradation of Dlg in cells with high PKA levels is inhibited and this is dependent on phosphorylation of the PDZ binding site in E6. In contrast, the degradation of p53 induced by E6 is not affected by PKA. We propose a differential regulation of E6 for the ubiquitin mediated degradation of specific E6 target proteins.

Oncogenic human papillomavirus E6 proteins target the discs large tumour suppressor for proteasome-mediated degradation

Previous studies have shown that the oncogenic HPV E6 proteins form a complex with the human homologue of the Drosophila tumour suppressor protein, discs large (Dlg). This is mediated by the carboxy terminus of the E6 proteins and involves recognition of at least one PDZ domain of Dlg. This region of E6 is not conserved amongst E6 proteins from the low risk papillomavirus types and, hence, binding of HPV E6 proteins to Dlg correlates with the oncogenic potential of these viruses. We have performed studies to investigate the consequences of the interaction between E6 and Dlg. Mutational analysis of both the HPV18 E6 and Dlg proteins has further defined the regions of E6 and Dlg necessary for complex formation. Strikingly, co-expression of wild type HPV18 E6 with Dlg in vitro or in vivo results in a dramatic decrease in the amount of Dlg protein, whereas mutants of E6 which fail to complex with Dlg have minimal effect on Dlg protein levels. The oncogenic HPV16 E6 also decreased the Dlg levels, but this was not observed with the low risk HPV11 E6 protein. Moreover, a region within the first 544 amino acids of Dlg containing the three PDZ domains confers susceptibility to E6 mediated degradation. Finally, treatment of cells with a proteasome inhibitor overrides the capacity of E6 to degrade Dlg. These results demonstrate that Dlg is targeted by high risk HPV E6 proteins for proteasome mediated degradation.

Molecular genetic characterisation of intracerebrally transplanted brain tumours

The aim of the present study was the characterisation of genetic alterations in two different experimental gliomas, induced in rats from the inbred strain BDIX by transplacental ethylnitrosourea with subsequent serial transplantation. The genes investigated have been shown previously to be altered during human glial tumour progression and include the gene for the epidermal growth factor receptor (EGFR), the genes for the cell cycle regulators cyclin dependent kinase 4 (CDK4), cyclinD1 (cycD1), the p16 gene (MTS1/INK4) and the retinoblastoma gene (RB). Using a semi-quantitative PCR-based screening method no gross alterations could be detected in these genes, demonstrating that nitrosourea-induced glial tumours of rats do not harbour those genetic changes which typically arise in human malignant gliomas. Thus, the use of this tumour model for gene therapy trials is questionable.

E3-ubiquitin ligase/E6-AP links multicopy maintenance protein 7 to the ubiquitination pathway by a novel motif, the L2G box

Ubiquitin ligases are generally assumed to play a major role in substrate recognition and thus provide specificity to a particular ubiquitin modification system. The multicopy maintenance protein (Mcm) 7 subunit of the replication licensing factor-M was identified as a substrate of the E3-ubiquitin ligase/E6-AP by its interaction with human papillomavirus-18E6. Mcm7 is ubiquitinated in vivo in both an E6-AP-dependent and -independent manner. E6-AP functions in these reactions independently of the viral oncogene E6. We show that recognition of Mcm7 by E6-AP is mediated by a homotypic interaction motif present in both proteins, called the L2G box. These findings served as the basis for the definition of substrate specificity for E6-AP. A small cluster of proteins whose function is intimately associated with the control of cell growth and/or proliferation contains the L2G box and is thereby implicated in an E6-AP and, by default, HPV-E6-dependent ubiquitination pathway.

[Routine hip ultrasonography in inflammatory rheumatoid diseases. Results in 119 consecutive patients of a rheumatism clinic]

METHOD

In 119 consecutive inpatients with rheumatic diseases--mainly rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis--both hips were routinely investigated by sonography.

RESULTS

In 52 of the 119 patients definite or possible pathological findings (in 18 cases bilateral) were observed. The relative frequency of sonographic findings in 223 evaluable hips was 33% and was somewhat higher in patients with rheumatoid arthritis than in those with other diagnoses. Changes were found significantly more often when the patient had joint complaints, limitation of movement, pathological X-ray changes or serological signs of inflammation (elevated ESR, positive C-reactive protein). The relative frequencies were higher than were expected on the basis of data in the literature. Of the pathological sonographic findings, 22% occurred in clinically and radiologically asymptomatic patients.

CONCLUSIONS

In view of the therapeutic consequences and the importance of early treatment, routine sonographic examination of the hip joint is recommended.

Cell cycle regulation of p70 S6 kinase and p42/p44 mitogen-activated protein kinases in Swiss mouse 3T3 fibroblasts

We show here using synchronized Swiss mouse 3T3 fibroblasts that p70 S6 kinase (p70S6k) and mitogen-activated protein kinases (p42mapk/p44mapk) are not only activated at the G0/G1 boundary, but also in cells progressing from M into G1. p70S6k activity increases 20-fold in G1 cells released from G0. Throughout G1, S, and G2 it decreases constantly, so that during M phase low kinase activity is measured. The kinase is reactivated 10-fold when cells released from a nocodazole-induced metaphase block enter G1 of the next cell cycle. p42mapk/p44mapk in G0 cells are activated transiently early in G1 and are reactivated late in mitosis after nocodazole release. p70S6k activity is dependent on permanent signaling from growth factors at all stages of the cell cycle. Immunofluorescence studies showed that p70S6k and its isoform p85S6k become concentrated in localized spots in the nucleus at certain stages in the cell cycle. Cell cycle-dependent changes in p70S6k activity are associated with alterations in the phosphorylation state of the protein. However, examination of the regulation of a p70S6k mutant in which the four carboxyl-terminal phosphorylation sites are changed to acidic amino acids suggests that a mechanism independent of these phosphorylation sites controls the activity of the enzyme during the cell cycle.

Scp160p, a new yeast protein associated with the nuclear membrane and the endoplasmic reticulum, is necessary for maintenance of exact ploidy

We have cloned a new gene, SCP160, from Saccharomyces cerevisiae, the deduced amino acid sequence of which does not exhibit overall similarity to any known yeast protein. A weak resemblance between the C-terminal part of the Scp160 protein and regulatory subunits of cAMP-dependent protein kinases from eukaryotes as well as the pstB protein of Escherichia coli was observed. The SCP160 gene resides on the left arm of chromosome X and codes for a polypeptide of molecular weight around 160 kDa. By immunofluorescence microscopy the Scp160 protein appears to be localized to the nuclear envelope and to the endoplasmic reticulum (ER). However, no signal sequence or membrane-spanning region exists, suggesting that the Scp160 protein is attached to the cytoplasmic surface of the ER-nuclear envelope membranes. Disruption of the SCP160 gene is not lethal but results in cells of decreased viability, abnormal morphology and increased DNA content. This phenotype is not reversible by transformation with a plasmid carrying the wild-type gene. Crosses of SCP160 deletion mutant strains among each other or with unrelated strains lead to irregular segregation of genetic markers. Taken together the data suggest that the Scp160 protein is required during cell division for faithful partitioning of the ER-nuclear envelope membranes which in S. cerevisiae enclose the duplicated chromosomes.

[Clinical relevance of the antiphospholipid syndrome. Antiphospholipid antibodies in a mixed rheumatologic patient sample]

The antiphospholipid syndrome may occur either in association with systemic lupus erythematosus (SLE) or as a primary condition. Diagnostic criteria include the detection of antiphospholipid antibodies using cardiolipin antigen (anticardiolipin antibodies, ACA) or lupus anticoagulant, and at least two clinical manifestations, primarily venous or arterial thrombosis, thrombocytopenia or repeated miscarriage. Among 200 patients with various rheumatic diseases, a pathological ACA test in excess of 44 U/ml was detected with ELISA in 81 cases (41%), and of these 30% had values exceeding 100 U/ml. Both overall positive reactions and the particularly high titers were clearly more common among patients with rheumatoid arthritis (RA) and collagen disease, namely 51% and 33%, respectively, than in patients with sero-negative spondylarthritis and non-inflammatory diseases of the locomotory system (22% pathological, 13% highly pathological, titers. Correlations were also found with miscarriage in women, positive rheumatoid and antinuclear factors, and the number of diagnostic criteria of RA or SLE presenting. A questionnaire survey - evaluating 84 subjects, half with positive and half with negative, ACA reactions - confirmed the correlation between miscarriage and the detection of ACA.

A new pair of B-type cyclins from Saccharomyces cerevisiae that function early in the cell cycle

Two new B-type cyclin genes from Saccharomyces cerevisiae, called CLB5 and CLB6, are located in a tail to tail arrangement adjacent to the G2/M phase promoting cyclins CLB2 and CLB1, respectively. These genomic cyclin arrays are flanked by tRNAs and repeated sequences of Ty elements suggesting an intrachromosomal gene duplication followed by an interchromosomal gene duplication. Based on their deduced protein sequence the CLB5 and CLB6 genes form a new pair of B-type cyclins. They are most related to each other and then to the deduced protein sequence of their adjacent genes CLB1 and CLB2. Both genes are periodically expressed, peaking early in the cell cycle. Loss of function mutants are viable, but clb5- mutants exhibit a delay in S phase whereas clb6- mutants show a delay in late G1 and/or S phase. The clb5 mutant phenotype is somewhat more pronounced in a double null mutant. Both cyclins have the potential to interact with the p34CDC28 kinase in vivo.