TY  - JOUR
A1  - Guth, Sabine
A1  - Hüser, Stephanie
A1  - Roth, Angelika
A1  - Degen, Gisela
A1  - Diel, Patrick
A1  - Edlund, Karolina
A1  - Eisenbrand, Gerhard
A1  - Engel, Karl-Heinz
A1  - Epe, Bernd
A1  - Grune, Tilman
A1  - Heinz, Volker
A1  - Henle, Thomas
A1  - Humpf, Hans-Ulrich
A1  - Jäger, Henry
A1  - Joost, Hans-Georg
A1  - Kulling, Sabine E.
A1  - Lampen, Alfonso
A1  - Mally, Angela
A1  - Marchan, Rosemarie
A1  - Marko, Doris
A1  - Mühle, Eva
A1  - Nitsche, Michael A.
A1  - Röhrdanz, Elke
A1  - Stadler, Richard
A1  - van Thriel, Christoph
A1  - Vieths, Stefan
A1  - Vogel, Rudi F.
A1  - Wascher, Edmund
A1  - Watzl, Carsten
A1  - Nöthlings, Ute
A1  - Hengstler, Jan G.
T1  - Contribution to the ongoing discussion on fluoride toxicity
JF  - Archives of Toxicology
N2  - Since the addition of fluoride to drinking water in the 1940s, there have been frequent and sometimes heated discussions regarding its benefits and risks. In a recently published review, we addressed the question if current exposure levels in Europe represent a risk to human health. This review was discussed in an editorial asking why we did not calculate benchmark doses (BMD) of fluoride neurotoxicity for humans. Here, we address the question, why it is problematic to calculate BMDs based on the currently available data. Briefly, the conclusions of the available studies are not homogeneous, reporting negative as well as positive results; moreover, the positive studies lack control of confounding factors such as the influence of well-known neurotoxicants. We also discuss the limitations of several further epidemiological studies that did not meet the inclusion criteria of our review. Finally, it is important to not only focus on epidemiological studies. Rather, risk analysis should consider all available data, including epidemiological, animal, as well as in vitro studies. Despite remaining uncertainties, the totality of evidence does not support the notion that fluoride should be considered a human developmental neurotoxicant at current exposure levels in European countries.
KW  - pharmacology/toxicology
KW  - occupational medicine/industrial medicine
KW  - environmental health
KW  - biomedicine, general
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-307161
SN  - 0340-5761
SN  - 1432-0738
VL  - 95
IS  - 7
ER  - 
TY  - JOUR
A1  - Barile, Frank A.
A1  - Berry, Colin
A1  - Blaauboer, Bas
A1  - Boobis, Alan
A1  - Bolt, Herrmann M.
A1  - Borgert, Christopher
A1  - Dekant, Wolfgang
A1  - Dietrich, Daniel
A1  - Domingo, Jose L.
A1  - Galli, Corrado L.
A1  - Gori, Gio Batta
A1  - Greim, Helmut
A1  - Hengstler, Jan G.
A1  - Heslop-Harrison, Pat
A1  - Kacew, Sam
A1  - Marquardt, Hans
A1  - Mally, Angela
A1  - Pelkonen, Olavi
A1  - Savolainen, Kai
A1  - Testai, Emanuela
A1  - Tsatsakis, Aristides
A1  - Vermeulen, Nico P.
T1  - The EU chemicals strategy for sustainability: in support of the BfR position
JF  - Archives of Toxicology
N2  - The EU chemicals strategy for sustainability (CSS) asserts that both human health and the environment are presently threatened and that further regulation is necessary. In a recent Guest Editorial, members of the German competent authority for risk assessment, the BfR, raised concerns about the scientific justification for this strategy. The complexity and interdependence of the networks of regulation of chemical substances have ensured that public health and wellbeing in the EU have continuously improved. A continuous process of improvement in consumer protection is clearly desirable but any initiative directed towards this objective must be based on scientific knowledge. It must not confound risk with other factors in determining policy. This conclusion is fully supported in the present Commentary including the request to improve both, data collection and the time-consuming and bureaucratic procedures that delay the publication of regulations.
KW  - pharmacology/toxicology
KW  - occupational medicine/industrial medicine
KW  - environmental health
KW  - biomedicine, general
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-307154
SN  - 0340-5761
SN  - 1432-0738
VL  - 95
IS  - 9
ER  - 
TY  - JOUR
A1  - Rebs, Sabine
A1  - Streckfuss-Bömeke, Katrin
T1  - How can we use stem cell-derived cardiomyocytes to understand the involvement of energetic metabolism in alterations of cardiac function?
JF  - Frontiers in Molecular Medicine
N2  - Mutations in the mitochondrial-DNA or mitochondria related nuclear-encoded-DNA lead to various multisystemic disorders collectively termed mitochondrial diseases. One in three cases of mitochondrial disease affects the heart muscle, which is called mitochondrial cardiomyopathy (MCM) and is associated with hypertrophic, dilated, and noncompact cardiomyopathy. The heart is an organ with high energy demand, and mitochondria occupy 30%–40% of its cardiomyocyte-cell volume. Mitochondrial dysfunction leads to energy depletion and has detrimental effects on cardiac performance. However, disease development and progression in the context of mitochondrial and nuclear DNA mutations, remains incompletely understood. The system of induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CM) is an excellent platform to study MCM since the unique genetic identity to their donors enables a robust recapitulation of the predicted phenotypes in a dish on a patient-specific level. Here, we focus on recent insights into MCM studied by patient-specific iPSC-CM and further discuss research gaps and advances in metabolic maturation of iPSC-CM, which is crucial for the study of mitochondrial dysfunction and to develop novel therapeutic strategies.
KW  - mitochondrial cardiomyopathy
KW  - iPSC-cardiomyocytes
KW  - maturation strategies
KW  - Barth syndrome
KW  - Friedreich’s ataxia
KW  - lysosomal storage disorders
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-327344
VL  - 3
ER  - 
TY  - JOUR
A1  - Harnoš, Jakub
A1  - Cañizal, Maria Consuelo Alonso
A1  - Jurásek, Miroslav
A1  - Kumar, Jitender
A1  - Holler, Cornelia
A1  - Schambony, Alexandra
A1  - Hanáková, Kateřina
A1  - Bernatík, Ondřej
A1  - Zdráhal, Zbynêk
A1  - Gömöryová, Kristína
A1  - Gybeľ, Tomáš
A1  - Radaszkiewicz, Tomasz Witold
A1  - Kravec, Marek
A1  - Trantírek, Lukáš
A1  - Ryneš, Jan
A1  - Dave, Zankruti
A1  - Fernández-Llamazares, Ana Iris
A1  - Vácha, Robert
A1  - Tripsianes, Konstantinos
A1  - Hoffmann, Carsten
A1  - Bryja, Vítězslav
T1  - Dishevelled-3 conformation dynamics analyzed by FRET-based biosensors reveals a key role of casein kinase 1
JF  - Nature Communications
N2  - Dishevelled (DVL) is the key component of the Wnt signaling pathway. Currently, DVL conformational dynamics under native conditions is unknown. To overcome this limitation, we develop the Fluorescein Arsenical Hairpin Binder- (FlAsH-) based FRET in vivo approach to study DVL conformation in living cells. Using this single-cell FRET approach, we demonstrate that (i) Wnt ligands induce open DVL conformation, (ii) DVL variants that are predominantly open, show more even subcellular localization and more efficient membrane recruitment by Frizzled (FZD) and (iii) Casein kinase 1 ɛ (CK1ɛ) has a key regulatory function in DVL conformational dynamics. In silico modeling and in vitro biophysical methods explain how CK1ɛ-specific phosphorylation events control DVL conformations via modulation of the PDZ domain and its interaction with DVL C-terminus. In summary, our study describes an experimental tool for DVL conformational sampling in living cells and elucidates the essential regulatory role of CK1ɛ in DVL conformational dynamics.
KW  - biological techniques
KW  - cell signalling
KW  - phosphorylation
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227837
VL  - 10
ER  - 
TY  - JOUR
A1  - Joos, J. P.
A1  - Saadatmand, A. R.
A1  - Schnabel, C.
A1  - Viktorinová, I.
A1  - Brand, T.
A1  - Kramer, M.
A1  - Nattel, S.
A1  - Dobrev, D.
A1  - Tomancak, P.
A1  - Backs, J.
A1  - Kleinbongard, P.
A1  - Heusch, G.
A1  - Lorenz, K.
A1  - Koch, E.
A1  - Weber, S.
A1  - El-Armouche, A.
T1  - Ectopic expression of S28A-mutated Histone H3 modulates longevity, stress resistance and cardiac function in Drosophila
JF  - Scientific Reports
N2  - Histone H3 serine 28 (H3S28) phosphorylation and de-repression of polycomb repressive complex (PRC)-mediated gene regulation is linked to stress conditions in mitotic and post-mitotic cells. To better understand the role of H3S28 phosphorylation in vivo, we studied a Drosophila strain with ectopic expression of constitutively-activated H3S28A, which prevents PRC2 binding at H3S28, thus mimicking H3S28 phosphorylation. H3S28A mutants showed prolonged life span and improved resistance against starvation and paraquat-induced oxidative stress. Morphological and functional analysis of heart tubes revealed smaller luminal areas and thicker walls accompanied by moderately improved cardiac function after acute stress induction. Whole-exome deep gene-sequencing from isolated heart tubes revealed phenotype-corresponding changes in longevity-promoting and myotropic genes. We also found changes in genes controlling mitochondrial biogenesis and respiration. Analysis of mitochondrial respiration from whole flies revealed improved efficacy of ATP production with reduced electron transport-chain activity. Finally, we analyzed posttranslational modification of H3S28 in an experimental heart failure model and observed increased H3S28 phosphorylation levels in HF hearts. Our data establish a critical role of H3S28 phosphorylation in vivo for life span, stress resistance, cardiac and mitochondrial function in Drosophila. These findings may pave the way for H3S28 phosphorylation as a putative target to treat stress-related disorders such as heart failure.
KW  - cardiac hypertrophy
KW  - epigenetics
KW  - heart failure
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-323637
VL  - 8
ER  - 
TY  - JOUR
A1  - Hommers, L. G.
A1  - Richter, J.
A1  - Yang, Y.
A1  - Raab, A.
A1  - Baumann, C.
A1  - Lang, K.
A1  - Schiele, M. A.
A1  - Weber, H.
A1  - Wittmann, A.
A1  - Wolf, C.
A1  - Alpers, G. W.
A1  - Arolt, V.
A1  - Domschke, K.
A1  - Fehm, L.
A1  - Fydrich, T.
A1  - Gerlach, A.
A1  - Gloster, A. T.
A1  - Hamm, A. O.
A1  - Helbig-Lang, S.
A1  - Kircher, T.
A1  - Lang, T.
A1  - Pané-Farré, C. A.
A1  - Pauli, P.
A1  - Pfleiderer, B.
A1  - Reif, A.
A1  - Romanos, M.
A1  - Straube, B.
A1  - Ströhle, A.
A1  - Wittchen, H.-U.
A1  - Frantz, S.
A1  - Ertl, G.
A1  - Lohse, M. J.
A1  - Lueken, U.
A1  - Deckert, J.
T1  - A functional genetic variation of SLC6A2 repressor hsa-miR-579-3p upregulates sympathetic noradrenergic processes of fear and anxiety
JF  - Translational Psychiatry
N2  - Increased sympathetic noradrenergic signaling is crucially involved in fear and anxiety as defensive states. MicroRNAs regulate dynamic gene expression during synaptic plasticity and genetic variation of microRNAs modulating noradrenaline transporter gene (SLC6A2) expression may thus lead to altered central and peripheral processing of fear and anxiety. In silico prediction of microRNA regulation of SLC6A2 was confirmed by luciferase reporter assays and identified hsa-miR-579-3p as a regulating microRNA. The minor (T)-allele of rs2910931 (MAFcases = 0.431, MAFcontrols = 0.368) upstream of MIR579 was associated with panic disorder in patients (pallelic = 0.004, ncases = 506, ncontrols = 506) and with higher trait anxiety in healthy individuals (pASI = 0.029, pACQ = 0.047, n = 3112). Compared to the major (A)-allele, increased promoter activity was observed in luciferase reporter assays in vitro suggesting more effective MIR579 expression and SLC6A2 repression in vivo (p = 0.041). Healthy individuals carrying at least one (T)-allele showed a brain activation pattern suggesting increased defensive responding and sympathetic noradrenergic activation in midbrain and limbic areas during the extinction of conditioned fear. Panic disorder patients carrying two (T)-alleles showed elevated heart rates in an anxiety-provoking behavioral avoidance test (F(2, 270) = 5.47, p = 0.005). Fine-tuning of noradrenaline homeostasis by a MIR579 genetic variation modulated central and peripheral sympathetic noradrenergic activation during fear processing and anxiety. This study opens new perspectives on the role of microRNAs in the etiopathogenesis of anxiety disorders, particularly their cardiovascular symptoms and comorbidities.
KW  - clinical genetics
KW  - psychiatric disorders
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-322497
VL  - 8
ER  - 
TY  - JOUR
A1  - Hartmann, Nico
A1  - Knierim, Maria
A1  - Maurer, Wiebke
A1  - Dybkova, Nataliya
A1  - Hasenfuß, Gerd
A1  - Sossalla, Samuel
A1  - Streckfuss-Bömeke, Katrin
T1  - Molecular and functional relevance of Na\(_V\)1.8-induced atrial arrhythmogenic triggers in a human SCN10A knock-out stem cell model
JF  - International Journal of Molecular Sciences
N2  - In heart failure and atrial fibrillation, a persistent Na\(^+\) current (I\(_{NaL}\)) exerts detrimental effects on cellular electrophysiology and can induce arrhythmias. We have recently shown that Na\(_V\)1.8 contributes to arrhythmogenesis by inducing a I\(_{NaL}\). Genome-wide association studies indicate that mutations in the SCN10A gene (Na\(_V\)1.8) are associated with increased risk for arrhythmias, Brugada syndrome, and sudden cardiac death. However, the mediation of these Na\(_V\)1.8-related effects, whether through cardiac ganglia or cardiomyocytes, is still a subject of controversial discussion. We used CRISPR/Cas9 technology to generate homozygous atrial SCN10A-KO-iPSC-CMs. Ruptured-patch whole-cell patch-clamp was used to measure the I\(_{NaL}\) and action potential duration. Ca\(^{2+}\) measurements (Fluo 4-AM) were performed to analyze proarrhythmogenic diastolic SR Ca\(^{2+}\) leak. The I\(_{NaL}\) was significantly reduced in atrial SCN10A KO CMs as well as after specific pharmacological inhibition of Na\(_V\)1.8. No effects on atrial APD\(_{90}\) were detected in any groups. Both SCN10A KO and specific blockers of Na\(_V\)1.8 led to decreased Ca\(^{2+}\) spark frequency and a significant reduction of arrhythmogenic Ca\(^{2+}\) waves. Our experiments demonstrate that Na\(_V\)1.8 contributes to I\(_{NaL}\) formation in human atrial CMs and that Na\(_V\)1.8 inhibition modulates proarrhythmogenic triggers in human atrial CMs and therefore Na\(_V\)1.8 could be a new target for antiarrhythmic strategies.
KW  - Na\(_V\)1.8
KW  - iPSC-cardiomyocytes
KW  - late Na\(^+\) current (I\(_{NaL}\))
KW  - CRISPR Cas9
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-362708
SN  - 1422-0067
VL  - 24
IS  - 12
ER  - 
TY  - JOUR
A1  - Meral, Derya
A1  - Provasi, Davide
A1  - Prada-Gracia, Diego
A1  - Möller, Jan
A1  - Marino, Kristen
A1  - Lohse, Martin J.
A1  - Filizola, Marta
T1  - Molecular details of dimerization kinetics reveal negligible populations of transient µ-opioid receptor homodimers at physiological concentrations
JF  - Scientific Reports
N2  - Various experimental and computational techniques have been employed over the past decade to provide structural and thermodynamic insights into G Protein-Coupled Receptor (GPCR) dimerization. Here, we use multiple microsecond-long, coarse-grained, biased and unbiased molecular dynamics simulations (a total of ~4 milliseconds) combined with multi-ensemble Markov state models to elucidate the kinetics of homodimerization of a prototypic GPCR, the µ-opioid receptor (MOR), embedded in a 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/cholesterol lipid bilayer. Analysis of these computations identifies kinetically distinct macrostates comprising several different short-lived dimeric configurations of either inactive or activated MOR. Calculated kinetic rates and fractions of dimers at different MOR concentrations suggest a negligible population of MOR homodimers at physiological concentrations, which is supported by acceptor photobleaching fluorescence resonance energy transfer (FRET) experiments. This study provides a rigorous, quantitative explanation for some conflicting experimental data on GPCR oligomerization.
KW  - computational biophysics
KW  - fluorescence resonance energy transfer
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-223995
VL  - 8
ER  -