AIM: Vericiguat significantly reduced the primary composite outcome of heart failure (HF) hospitalization or cardiovascular death in the VICTORIA trial. It is unknown if these outcome benefits are related to reverse left ventricular (LV) remodelling with vericiguat in patients with HF with reduced ejection fraction (HFrEF). The aim of this study was to compare the effects of vericiguat versus placebo on LV structure and function after 8 months of therapy in patients with HFrEF. METHODS AND RESULTS: Standardized transthoracic echocardiography (TTE) was performed at baseline and after 8 months of therapy in a subset of HFrEF patients in VICTORIA. The co-primary endpoints were changes in LV end-systolic volume index (LVESVI) and LV ejection fraction (LVEF). Quality assurance and central reading were performed by an echocardiographic core laboratory blinded to treatment assignment. A total of 419 patients (208 vericiguat, 211 placebo) with high-quality paired TTE at baseline and 8 months were included. Baseline clinical characteristics were well balanced between treatment groups and echocardiographic characteristics were representative of patients with HFrEF. LVESVI significantly declined (60.7 ± 26.8 to 56.8 ± 30.4 ml/m2 ; p < 0.01) and LVEF significantly increased (33.0 ± 9.4% to 36.1 ± 10.2%; p < 0.01) in the vericiguat group, but similarly in the placebo group (absolute changes for vericiguat vs. placebo: LVESVI -3.8 ± 15.4 vs. -7.1 ± 20.5 ml/m2 ; p = 0.07 and LVEF +3.2 ± 8.0% vs. +2.4 ± 7.6%; p = 0.31). The absolute rate per 100 patient-years of the primary composite endpoint at 8 months tended to be lower in the vericiguat group (19.8) than the placebo group (29.6) (p = 0.07). CONCLUSIONS: In this pre-specified echocardiographic study, significant improvements in LV structure and function occurred over 8 months in both vericiguat and placebo in a high-risk HFrEF population with recent worsening HF. Further studies are warranted to define the mechanisms of vericiguat's benefit in HFrEF.

• Keywords
• Echocardiography, Heart failure with reduced ejection fraction, Left ventricular function, Left ventricular structure, Vericiguat,
• MeSH
• Echocardiography MeSH
• Ventricular Function, Left MeSH
• Heterocyclic Compounds, 2-Ring * MeSH
• Humans MeSH
• Heart Failure * diagnostic imaging   drug therapy   chemically induced   MeSH
• Stroke Volume MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Heterocyclic Compounds, 2-Ring * MeSH
• vericiguat MeSH Browser

The GPCR signalling cascade is a key pathway responsible for the signal transduction of a multitude of physical and chemical stimuli, including light, odorants, neurotransmitters and hormones. Understanding the structural and functional properties of the GPCR cascade requires direct observation of signalling processes in high spatial and temporal resolution, with minimal perturbation to endogenous systems. Optical microscopy and spectroscopy techniques are uniquely suited to this purpose because they excel at multiple spatial and temporal scales and can be used in living objects. Here, we review recent developments in microscopy and spectroscopy technologies which enable new insights into GPCR signalling. We focus on advanced techniques with high spatial and temporal resolution, single-molecule methods, labelling strategies and approaches suitable for endogenous systems and large living objects. This review aims to assist researchers in choosing appropriate microscopy and spectroscopy approaches for a variety of applications in the study of cellular signalling. LINKED ARTICLES: This article is part of a themed issue Complexity of GPCR Modulation and Signaling (ERNST). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v182.14/issuetoc.

• Keywords
• G protein, G protein‐coupled receptor, biosensors, cell signalling, microscopy, spectroscopy, super‐resolution,
• MeSH
• Humans MeSH
• Microscopy * methods   MeSH
• Receptors, G-Protein-Coupled * chemistry   metabolism   MeSH
• Signal Transduction MeSH
• Spectrum Analysis * methods   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• Receptors, G-Protein-Coupled * MeSH

BACKROUND AND AIMS: Early evaluation of cardiac remodeling may be useful in predicting heart failure in patients with arterial hypertension. The identification of biomarkers as useful clinical tools in this regard is ongoing. The aim of this study was to evaluate the association of selected cardiac biomarkers levels with parameters of cardiac structure and function in patients with arterial hypertension. PATIENTS AND METHODS: Included in the study were patients with arterial hypertension with normal left ventricular ejection fraction (LV EF) and absence of signs of heart failure. The levels of selected biomarkers: NT-proBNP, sST2, Galectin-3, GDF-15, Cystatin C, TIMP-1 and ceruloplasmin were measured and assessed together with other biochemical and echocardiographic parameters. RESULTS: A total of 92 patients (61% men) mean age 61.5 years were included. Mean LV EF was 64.7% and mean LV mass index was 91.7 g/m2. NT-proBNP level correlated significantly with the parameters of LV diastolic function: velocity of E wave (r=0.377, P<0.002), and with E/A ratio, (r=0.455, P<0.0001), with E lat (r=-0.354, P=0.006), E/E' ratio, r=0.393, P<0.002, with ePAP (r=0.390, P=0.014), and with age (r=0.384, P<0.0001). Statistically significant correlations for GDF-15 were as follows: with age (r=0.426, P<0.0001) and left atrial diameter (LA) (r=0.401, P<0.0001), for Cystatin C there are statistically significant correlation with age (r=0.288, P=0.006) and LA (r=0.329, P=0.004). Only sST2 level correlated significantly with parameters of cardiac structure: with LV mass (r=0.290, P<0.01) and LV mass index (r=0.307, P=0.012) and with posterior wall thickness PW (r=0.380, P<0.001). No other observed variables including Galectin-3 and TIMP-1, correlated significantly with age or echocardiographic variables. In a comparison of patients with and without left ventricular hypertrophy, statistically significant differences were found only in LA (P<0.0001) and sST2 (P=0.004). In a multivariate logistic regression, sST2 and TIMP were independent predictors of left ventricular hypertrophy. CONCLUSION: NT-proBNP level as a biomarker of cardiac remodeling correlated with parameters of LV diastolic function in patients with arterial hypertension. Soluble ST2 correlated with parameters of cardiac structure. Biomarkers sST2 and TIMP-1 were associated with left ventricular hypertrophy.

• Keywords
• NT-proBNP, TIMP-1, arterial hypertension, biomarkers, cardiac structure, heart function, sST2,
• Publication type
• Journal Article MeSH

Quantitative structure-function relationships (QSFR) and quantitative structure-stability relationships (QSSR) analyses are described here. The objective of these analyses is to investigate and quantitatively describe the effect of the changes in structure of protein on its function or stability. During the analysis, the structural and physico-chemical properties of the amino acid residues are related to activity or stability data derived for the group of proteins containing systematic substitutions at certain positions. Four examples of the application of these analyses on the data obtained with proteins modified by site-directed mutagenesis experiments are provided. Structure-function relationships were studied for 15 mutants in position 172 of the haloalkane dehalogenase and 19 mutants in position 222 of the subtilisin, while the structure-stability relationships were investigated for 13 mutants in position 157 of phage T4 lysozyme and 18 mutants in position 49 of alpha-subunits tryptophan synthase. A total of 402 molecular descriptors derived from AAindex database were used to quantify amino acid properties and the multivariate statistical technique--partial least squares projections to latent structures--was used to identify those of them which are important for explanation of the activity and stability data. Quantitative models were developed and internally validated for every data set. The possibilities for further development of both analyses and their application for predictive and analytical purposes in protein engineering research are discussed.

• MeSH
• Glutamic Acid chemistry   MeSH
• Mutagenesis, Site-Directed MeSH
• Protein Engineering MeSH
• Thermodynamics MeSH
• Tryptophan Synthase chemistry   genetics   MeSH
• Structure-Activity Relationship MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Glutamic Acid MeSH
• Tryptophan Synthase MeSH

We lack a predictive understanding of the environmental drivers determining the structure and function of archaeal communities as well as the proteome associated with these important soil organisms. Here, we characterized the structure (by 16S rRNA gene sequencing) and function (by metaproteomics) of archaea from 32 soil samples across terrestrial ecosystems with contrasting climate and vegetation types. Our multi-"omics" approach unveiled that genes from Nitrosophaerales and Thermoplasmata dominated soils collected from four continents, and that archaea comprise 2.3 ± 0.3% of microbial proteins in these soils. Aridity positively correlated with the proportion of Nitrosophaerales genes and the number of archaeal proteins. The interaction of climate x vegetation shaped the functional profile of the archaeal community. Our study provides novel insights into the structure and function of soil archaea across climates, and highlights that these communities may be influenced by increasing global aridity.

• Keywords
• 16S rRNA gene amplicon sequencing, Archaea, Climate, Metaproteomics, Soil, Vegetation,
• MeSH
• Archaea * genetics   MeSH
• Ecosystem MeSH
• Soil * MeSH
• Soil Microbiology MeSH
• RNA, Ribosomal, 16S MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Soil * MeSH
• RNA, Ribosomal, 16S MeSH

The TERT (telomerase reverse transcriptase) subunit of telomerase is an intensively studied macromolecule due to its key importance in maintaining genome integrity and role in cellular aging and cancer. In an effort to provide an up-to-date overview of the topic, we discuss the structure of TERT genes, their alternative splicing products and their functions. Nucleotide databases contain more than 90 full-length cDNA sequences of telomerase protein subunits. Numerous in silico, in vitro and in vivo experimental techniques have revealed a great deal of structural and functional data describing particular features of the telomerase subunit in various model organisms. We explore whether particular findings are generally applicable to telomerases or species-specific. We also discuss in an evolutionary context the role of identified functional TERT subdomains.

• MeSH
• Alternative Splicing MeSH
• Eukaryotic Cells chemistry   enzymology   MeSH
• Humans MeSH
• Evolution, Molecular MeSH
• Molecular Sequence Data MeSH
• Prokaryotic Cells chemistry   enzymology   MeSH
• Telomerase chemistry   genetics   metabolism   MeSH
• Telomere metabolism   MeSH
• Protein Binding MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH
• Names of Substances
• Telomerase MeSH

Little is still known about the effect of dietary patterns on left ventricular hypertrophy (LVH). Here, we derived dietary patterns by principal component analysis (PCA) and evaluated their association with LV structure, function, and remodelling. Our cross-sectional study included 438 members (aged 25-65 years; 59.1% women) of the Kardiovize Brno 2030 with no history of cardiovascular disease. Two dietary patterns were derived using PCA, namely prudent and western. Primary outcomes were echocardiographic parameters and LV geometric patterns, such as concentric LV remodelling (cLVR), concentric LVH (cLVH), and eccentric LVH (eLVH). Interestingly, participants with high adherence to the prudent dietary pattern had decreased odds of cLVH after adjustment for socio-demographic, clinical and behavioral covariates (OR = 0.24, 95% CI = 0.08-0.88; p = 0.031). By contrast, several echocardiographic parameters increased with increasing adherence to the western dietary pattern, which resulted in higher odds of cLVH among participants with high adherence (OR = 5.38, 95% CI = 1.17-23.58; p = 0.035). Although our findings may have an immediate relevance for public-health strategies, further large-size prospective studies should be encouraged to better understand the observed association and their causality.

• MeSH
• Adult MeSH
• Electrocardiography MeSH
• Cardiomegaly pathology   physiopathology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Logistic Models MeSH
• Ventricular Remodeling * MeSH
• Aged MeSH
• Heart Ventricles diagnostic imaging   pathology   physiopathology   MeSH
• Feeding Behavior * MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

G-quadruplexes are noncanonical nucleic acid structures formed from stacked guanine tetrads. They are frequently used as building blocks and functional elements in fields such as synthetic biology and also thought to play widespread biological roles. G-quadruplexes are often studied as monomers, but can also form a variety of higher-order structures. This increases the structural and functional diversity of G-quadruplexes, and recent evidence suggests that it could also be biologically important. In this review, we describe the types of multimeric topologies adopted by G-quadruplexes and highlight what is known about their sequence requirements. We also summarize the limited information available about potential biological roles of multimeric G-quadruplexes and suggest new approaches that could facilitate future studies of these structures.

• Keywords
• DNA:RNA hybrid, G-quadruplex, R-loop, dimer, multimer, oligomer, promoter, telomere, tetramer,
• MeSH
• DNA chemistry   MeSH
• G-Quadruplexes * MeSH
• Nucleic Acid Conformation * MeSH
• Models, Molecular MeSH
• Molecular Structure MeSH
• RNA chemistry   MeSH
• Telomere MeSH
• Structure-Activity Relationship MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• DNA MeSH
• RNA MeSH

Membrane proteins are a large, diverse group of proteins, serving a multitude of cellular functions. They are difficult to study because of their requirement of a lipid membrane for function. Here we show that two-photon polarization microscopy can take advantage of the cell membrane requirement to yield insights into membrane protein structure and function, in living cells and organisms. The technique allows sensitive imaging of G-protein activation, changes in intracellular calcium concentration and other processes, and is not limited to membrane proteins. Conveniently, many suitable probes for two-photon polarization microscopy already exist.

• MeSH
• Cell Membrane metabolism   ultrastructure   MeSH
• Protein Conformation MeSH
• Membrane Proteins metabolism   ultrastructure   MeSH
• Microscopy, Fluorescence, Multiphoton methods   MeSH
• Microscopy, Polarization methods   MeSH
• Structure-Activity Relationship MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Membrane Proteins MeSH

Chemical cross-linking coupled with mass spectrometry is a popular technique for deriving structural information on proteins and protein complexes. Also, cross-linking has become a powerful tool for stabilizing macromolecular complexes for single-particle cryo-electron microscopy. However, an effect of cross-linking on protein structure and function should not be forgotten, and surprisingly, it has not been investigated in detail so far. Here, we used kinetic studies, mass spectrometry, and NMR spectroscopy to systematically investigate an impact of cross-linking on structure and function of human carbonic anhydrase and alcohol dehydrogenase 1 from Saccharomyces cerevisiae. We found that cross-linking induces rather local structural disturbances and the overall fold is preserved even at a higher cross-linker concentration. The results establish general experimental conditions for chemical cross-linking with minimal effect on protein structure and function.

• MeSH
• Alcohol Dehydrogenase chemistry   MeSH
• Mass Spectrometry MeSH
• Carbonic Anhydrases chemistry   MeSH
• Protein Conformation MeSH
• Humans MeSH
• Models, Molecular MeSH
• Protein Multimerization MeSH
• Nuclear Magnetic Resonance, Biomolecular MeSH
• Cross-Linking Reagents chemistry   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Alcohol Dehydrogenase MeSH
• Carbonic Anhydrases MeSH
• Cross-Linking Reagents MeSH