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We present a generic workflow combining physiology-based computational modeling and in vitro data to assess the clinical cholestatic risk of different drugs systematically. Changes in expression levels of genes involved in the enterohepatic circulation of bile acids were obtained from an in vitro assay mimicking 14 days of repeated drug administration for 10 marketed drugs. These changes in gene expression over time were contextualized in a physiology-based bile acid model of glycochenodeoxycholic acid. The simulated drug-induced response in bile acid concentrations was then scaled with the applied drug doses to calculate the cholestatic potential for each compound. A ranking of the cholestatic potential correlated very well with the clinical cholestasis risk obtained from medical literature. The proposed workflow allows benchmarking the cholestatic risk of novel drug candidates. We expect the application of our workflow to significantly contribute to the stratification of the cholestatic potential of new drugs and to support animal-free testing in future drug development.

In the areas of electronic identification and electronic trust services, the Regulation No. 910/2014 of the European Parliament and of the Council on electronic identification and trust services for electronic transactions in the internal market and repealing Directive 1999/93/EC (eIDAS) creates uniform regulations for electronic signatures, seals, time stamps, registered mail and website certificates in the European single market. All developments that affect the security of signature procedures have an impact. In this study, we consider the candidates for quantum computer-resistant asymmetric cryptographic (PQC) methods currently under investigation in international research and standardization and evaluate their suitability for PKI systems with a focus on long-term preservation of evidential value, as is the case in particular with eIDAS-compliant signature solutions. Based on an evaluation system proposed by us - an adaptation of the system from [2] - we compare the application requirements with the properties of the candidates and recommend suitable methods.

Uncovering cellular responses from heterogeneous genomic data is crucial for molecular medicine in particular for drug safety. This can be realized by integrating the molecular activities in networks of interacting proteins. As proof-of-concept we challenge network modeling with time-resolved proteome, transcriptome and methylome measurements in iPSC-derived human 3D cardiac microtissues to elucidate adverse mechanisms of anthracycline cardiotoxicity measured with four different drugs (doxorubicin, epirubicin, idarubicin and daunorubicin). Dynamic molecular analysis at in vivo drug exposure levels reveal a network of 175 disease-associated proteins and identify common modules of anthracycline cardiotoxicity in vitro, related to mitochondrial and sarcomere function as well as remodeling of extracellular matrix. These in vitro-identified modules are transferable and are evaluated with biopsies of cardiomyopathy patients. This to our knowledge most comprehensive study on anthracycline cardiotoxicity demonstrates a reproducible workflow for molecular medicine and serves as a template for detecting adverse drug responses from complex omics data., Using a network propagation approach with integrated multi-omic data, Selevsek et al. develop a reproducible workflow for identifying drug toxicity effects in cellular systems. This is demonstrated with the analysis of anthracycline cardiotoxicity in cardiac microtissues under the effect of multiple drugs.

Background and Aims A dysregulated phosphate homeostasis is strongly associated with mortality, cardiovascular events and vascular calcification, particularly in patients suffering from CKD. Inhibition of the tubular phosphate transporter Npt2a provides a novel and unique mechanism to address phosphate homeostasis imbalance and vascular calcification. Method Npt2a activity was measured in a cell-based assay, using a stable CHO cell line with inducible Npt2a expression. Male Wistar rats were used for all experiments. Healthy rats were treated orally with BAY 767, a potent Npt2a inhibitor developed at Bayer AG to assess urinary phosphate excretion. Vascular calcification was induced by administration of a pan-FGFR inh. (25mg/kg) for 10 days. Calcium content in the aorta was measured as surrogate for vascular calcification. Blood samples were withdrawn at the end of the study to determine the plasma levels of FGF-23, parathyroid hormone and phosphate with commercially available assay systems according to the manufactures protocols (FGF-23 and PTH: ELISA Kit, Immuntopics; phosphate: Pentra400 system). Results BAY 767 was identified as potent Npt2a inhibitor, with an IC50 of 2.9/6 nM on rat/ human Npt2a, respectively, selective over Npt2b, Npt2c and Pit-1. Single dose treatments of healthy rats resulted in a significant, dose-dependent increase in urinary phosphate excretion within 16h. In an experimental vascular calcification model, massive vascular calcification and hyperphosphatemia was induced by daily oral administration of a FGFR inh. Simultaneous treatment with the Npt2a inhibitor BAY 767 significantly inhibited vascular calcification in comparison to untreated rats. In this set-up the plasma phosphate level was increased after 10 days up to 3.7 mmol/L in the FGFR inh. treated group compared to 1.9 mmol/L in control animals, whilst treatment with BAY 767 reduced plasma levels to 2.7 mmol/L. In addition, FGF-23 and PTH were also reduced under compound BAY 767 treatment. However, in the same model 2.2% lanthanum carbonate was not beneficial with respect to vascular calcification. Conclusion Our results show for the first time that treatment with a Npt2a inhibitor improves vascular calcification by addressing urinary phosphate excretion and phosphate homeostasis in rats. Npt2a inhibition may provide a new therapeutic principle for patients suffering from disbalanced phosphate homeostasis and vascular calcifications, including CKD patients.

Die EU verdeutlicht mit den Verordnungen DSGVO und eIDAS-VO, dass Vertrauen in digitale Dienste eine wichtige Voraussetzung fur die Etablierung eines global wettbewerbsfahigen digitalen Binnenmarkts ist. Interessant sind einerseits die Unterschiede im Reifegrad der im Umfeld der jeweiligen Verordnungen existierenden Standardisierungen und andererseits die wechselseitigen Auswirkungen der beiden Verordnungen. Insbesondere stellt sich die Frage, wie sich der in ETSI/CEN-Normen geregelte eIDAS-Toolbaukasten (Siegel, Zeitstempel, Signaturen, Zustelldienste…) zur Umsetzung der Anforderungen der DSGVO bzw. der BDSG-neu einsetzen lasst.

Drug-induced perturbations of the endogenous metabolic network are a potential root cause of cellular toxicity. A mechanistic understanding of such unwanted side effects during drug therapy is therefore vital for patient safety. The comprehensive assessment of such drug-induced injuries requires the simultaneous consideration of both drug exposure at the whole-body and resulting biochemical responses at the cellular level. We here present a computational multi-scale workflow that combines whole-body physiologically based pharmacokinetic (PBPK) models and organ-specific genome-scale metabolic network (GSMN) models through shared reactions of the xenobiotic metabolism. The applicability of the proposed workflow is illustrated for isoniazid, a first-line antibacterial agent against Mycobacterium tuberculosis, which is known to cause idiosyncratic drug-induced liver injuries (DILI). We combined GSMN models of a human liver with N-acetyl transferase 2 (NAT2)-phenotype-specific PBPK models of isoniazid. The combined PBPK-GSMN models quantitatively describe isoniazid pharmacokinetics, as well as intracellular responses, and changes in the exometabolome in a human liver following isoniazid administration. Notably, intracellular and extracellular responses identified with the PBPK-GSMN models are in line with experimental and clinical findings. Moreover, the drug-induced metabolic perturbations are distributed and attenuated in the metabolic network in a phenotype-dependent manner. Our simulation results show that a simultaneous consideration of both drug pharmacokinetics at the whole-body and metabolism at the cellular level is mandatory to explain drug-induced injuries at the patient level. The proposed workflow extends our mechanistic understanding of the biochemistry underlying adverse events and may be used to prevent drug-induced injuries in the future., Systems toxicology: linking pharmacokinetics to endogenous metabolism The genotype of a patient determines the extent of drug-induced metabolic perturbations on the endogenous cellular network of the liver. A team around Lars Kuepfer at Germany’s RWTH Aachen University developed a computational workflow that links drug pharmacokinetics at the whole-body level with a cellular network of the liver. The authors used the competitive cofactor and energy demands in endogenous and drug metabolism to establish a multi-scale model for the antibiotic isoniazid. Their model quantitatively describes how isoniazid pharmacokinetics alter the intracellular liver biochemistry and the utilization of extracellular metabolites in different patient genotypes. The study outlines how a mechanistic understanding of genotype-dependent drug-induced metabolic perturbations may help to explain diverging incidence rates of toxic events in different patient subgroups. This could reduce the occurrence of toxic side effects during drug treatments in the future.

Ein international erfolgreiches Schema fur Cybersicherheits-Zertifizierungen bedarf akzeptierter und implementierter Sicherheitsstandards. Dieser Artikel erortert kritisch die komplexen Anforderungen hinsichtlich der Vollstandigkeit, Dynamik und Durchsetzung aus europaischer Perspektive und zeigt am Beispiel der eIDAS-Verordnung die Herausforderungen bei der Umsetzung auf.

Three-dimensional (3D) cell culture models are thought to mimic the physiological and pharmacological properties of tissues in vivo more accurately than two-dimensional cultures on plastic dishes. For the development of cancer therapies, 3D spheroid models are being created to reflect the complex histology and physiology of primary tumors with the hopes that drug responses will be more similar to and as predictive as those obtained in vivo. The effect of additional cell types in tumors, such as stromal cells, and the resulting heterotypic cell-cell crosstalk can be investigated in these heterotypic 3D cell cultures. Here, a high-throughput screening-compatible drug testing platform based on 3D multicellular spheroid models is described that enables the parallel assessment of toxicity on stromal cells and efficacy on cancer cells by drug candidates. These heterotypic microtissue tumor models incorporate NIH3T3 fibroblasts as stromal cells that are engineered with a reporter gene encoding secreted NanoLUC luciferase. By tracking the NanoLUC signal in the media over time, a time-related measurement of the cytotoxic effects of drugs on stromal cells over the cancer cells was possible, thus enabling the identification of a therapeutic window. An in vitro therapeutic index parameter is proposed to help distinguish and classify those compounds with broad cytotoxic effects versus those that are more selective at targeting cancer cells.

Bedingt durch eine durchgangige Verknupfung der Wertschopfungsketten (Industrie 4.0) und neue regulatorische Anforderungen mussen Managementsysteme ertuchtigt werden, Informationen verlasslich, vertrauenswurdig und medienbruchfrei auch fur externe Nutzer bereitzustellen. Der nachfolgende Artikel untersucht, inwieweit eIDAS basierende Vertrauensdienste einen Beitrag dazu leisten konnen.