Anthocyanins in Vascular Health and Disease: Mechanisms of Action and Therapeutic Potential.

ABSTRACT: Unhealthy lifestyles have placed a significant burden on individuals' cardiovascular health. Anthocyanins are water-soluble flavonoid pigments found in a wide array of common foods and fruits. Anthocyanins have the potential to contribute to the prevention and treatment of cardiovascular disease by improving lipid profiles and vascular function, reducing blood glucose levels and blood pressure, and inhibiting inflammation. These actions have been demonstrated in numerous clinical and preclinical studies. At the cellular and molecular level, anthocyanins and their metabolites could protect endothelial cells from senescence, apoptosis, and inflammation by activating the phosphoinositide 3-kinase/protein kinase B/endothelial nitric oxide synthases, silent information regulator 1 (SIRT1), or nuclear factor erythroid2-related factor 2 pathways and inhibiting the nuclear factor kappa B, Bax, or P38 mitogen-activated protein kinase pathways. Furthermore, anthocyanins prevent vascular smooth muscle cell from platelet-derived growth factor -induced or tumor necrosis factor-α-induced proliferation and migration by inhibiting the focal adhesion kinase and extracellular regulated protein kinases signaling pathways. Anthocyanins could also attenuate vascular inflammation by reducing the formation of oxidized lipids, preventing leukocyte adhesion and infiltration of the vessel wall, and macrophage phagocytosis of deposited lipids through reducing the expression of cluster of differentiation 36 and increasing the expression of ATP-binding cassette subfamily A member 1 and ATP-binding cassette subfamily G member 1. At the same time, anthocyanins could lower the risk of thrombosis by inhibiting platelet activation and aggregation through down-regulating P-selectin, transforming growth factor-1, and CD40L. Thus, the development of anthocyanin-based supplements or derivative drugs could provide new therapeutic approaches to the prevention and treatment of vascular diseases.

Employing targeted outreach to improve community involvement in detecting invasive Nile monitors (Varanus niloticus) in Florida.

We successfully employed targeted outreach to communities in Palm Beach County, Florida, to enhance detection of invasive reptiles. We defined targeted outreach as delivering a specific message to a specific audience, at a specific location, to obtain a specific result. These efforts improved our ability to solicit community involvement focused on target species of interest in locations at risk of potential establishment of incipient populations. From 2018 through 2020, we reached over 112,000 individuals who reported over 50 nonnative lizard sightings to EDDMapS, a web-based mapping system for documenting invasive species, and the State-managed IVE-GOT1 reporting hotline. We considered reports to be directly attributed to our outreach efforts when the reporter indicated our outreach method as the source from which they obtained information on reporting large invasive lizards. We found print media elicited the most reports, while social media reached the largest audience both in direct shares and spillover to additional communities outside our target area. We concluded that to help improve invasive species management programs, three tactics could be employed: (1) using multiple forms of media, (2) additional educational support to improve the accuracy of public reports, and (3) rapid, dedicated capability to respond to reported sightings.

EPAS1 Attenuates Atherosclerosis Initiation at Disturbed Flow Sites Through Endothelial Fatty Acid Uptake.

BACKGROUND: Atherosclerotic plaques form unevenly due to disturbed blood flow, causing localized endothelial cell (EC) dysfunction. Obesity exacerbates this process, but the underlying molecular mechanisms are unclear. The transcription factor EPAS1 (HIF2A) has regulatory roles in endothelium, but its involvement in atherosclerosis remains unexplored. This study investigates the potential interplay between EPAS1, obesity, and atherosclerosis. METHODS: Responses to shear stress were analyzed using cultured porcine aortic EC exposed to flow in vitro coupled with metabolic and molecular analyses and by en face immunostaining of murine aortic EC exposed to disturbed flow in vivo. Obesity and dyslipidemia were induced in mice via exposure to a high-fat diet or through Leptin gene deletion. The role of Epas1 in atherosclerosis was evaluated by inducible endothelial Epas1 deletion, followed by hypercholesterolemia induction (adeno-associated virus-PCSK9 [proprotein convertase subtilisin/kexin type 9]; high-fat diet). RESULTS: En face staining revealed EPAS1 enrichment at sites of disturbed blood flow that are prone to atherosclerosis initiation. Obese mice exhibited substantial reduction in endothelial EPAS1 expression. Sulforaphane, a compound with known atheroprotective effects, restored EPAS1 expression and concurrently reduced plasma triglyceride levels in obese mice. Consistently, triglyceride derivatives (free fatty acids) suppressed EPAS1 in cultured EC by upregulating the negative regulator PHD2. Clinical observations revealed that reduced serum EPAS1 correlated with increased endothelial PHD2 and PHD3 in obese individuals. Functionally, endothelial EPAS1 deletion increased lesion formation in hypercholesterolemic mice, indicating an atheroprotective function. Mechanistic insights revealed that EPAS1 protects arteries by maintaining endothelial proliferation by positively regulating the expression of the fatty acid-handling molecules CD36 and LIPG to increase fatty acid beta-oxidation. CONCLUSIONS: Endothelial EPAS1 attenuates atherosclerosis at sites of disturbed flow by maintaining EC proliferation via fatty acid uptake and metabolism. This endothelial repair pathway is inhibited in obesity, suggesting a novel triglyceride-PHD2 modulation pathway suppressing EPAS1 expression. These findings have implications for therapeutic strategies addressing vascular dysfunction in obesity.

Controversy in mechanotransduction - the role of endothelial cell-cell junctions in fluid shear stress sensing.

Fluid shear stress (FSS) from blood flow, sensed by the vascular endothelial cells (ECs) that line all blood vessels, regulates vascular development during embryogenesis, controls adult vascular physiology and determines the location of atherosclerotic plaque formation. Although a number of papers have reported a crucial role for cell-cell adhesions or adhesion receptors in these processes, a recent publication has challenged this paradigm, presenting evidence that ECs can very rapidly align in fluid flow as single cells without cell-cell contacts. To address this controversy, four independent laboratories assessed EC alignment in fluid flow across a range of EC cell types. These studies demonstrate a strict requirement for cell-cell contact in shear stress sensing over timescales consistent with previous literature and inconsistent with the newly published data.

Optical and electronic functionality arising from controlled defect formation in nanoscale complex oxide lateral epitaxy.

Epitaxial crystallization of complex oxides provides the means to create materials with precisely selected composition, strain, and orientation, thereby controlling their functionalities. Extending this control to nanoscale three-dimensional geometries can be accomplished via a three-dimensional analog of oxide solid-phase epitaxy, lateral epitaxial crystallization. The orientation of crystals within laterally crystallized SrTiO3 systematically changes from the orientation of the SrTiO3 substrate. This evolution occurs as a function of lateral crystallization distance, with a rate of approximately 50° µm-1. The mechanism of the rotation is consistent with a steady-state stress of tens of megapascal over a 100-nanometer scale region near the moving amorphous/crystalline interface arising from the amorphous-crystalline density difference. Second harmonic generation and piezoelectric force microscopy reveal that the laterally crystallized SrTiO3 is noncentrosymmetric and develops a switchable piezoelectric response at room temperature, illustrating the potential to use lateral crystallization to control the functionality of complex oxides.

Exploring the Origins and Evolution of Oxygenic and Anoxygenic Photosynthesis in Deeply Branched Cyanobacteriota.

Cyanobacteriota, the sole prokaryotes capable of oxygenic photosynthesis (OxyP), occupy a unique and pivotal role in Earth's history. While the notion that OxyP may have originated from Cyanobacteriota is widely accepted, its early evolution remains elusive. Here, by using both metagenomics and metatranscriptomics, we explore 36 metagenome-assembled genomes from hot spring ecosystems, belonging to two deep-branching cyanobacterial orders: Thermostichales and Gloeomargaritales. Functional investigation reveals that Thermostichales encode the crucial thylakoid membrane biogenesis protein, vesicle-inducing protein in plastids 1 (Vipp1). Based on the phylogenetic results, we infer that the evolution of the thylakoid membrane predates the divergence of Thermostichales from other cyanobacterial groups and that Thermostichales may be the most ancient lineage known to date to have inherited this feature from their common ancestor. Apart from OxyP, both lineages are potentially capable of sulfide-driven AnoxyP by linking sulfide oxidation to the photosynthetic electron transport chain. Unexpectedly, this AnoxyP capacity appears to be an acquired feature, as the key gene sqr was horizontally transferred from later-evolved cyanobacterial lineages. The presence of two D1 protein variants in Thermostichales suggests the functional flexibility of photosystems, ensuring their survival in fluctuating redox environments. Furthermore, all MAGs feature streamlined phycobilisomes with a preference for capturing longer-wavelength light, implying a unique evolutionary trajectory. Collectively, these results reveal the photosynthetic flexibility in these early-diverging cyanobacterial lineages, shedding new light on the early evolution of Cyanobacteriota and their photosynthetic processes.

Urolithin A promotes atherosclerotic plaque stability by limiting inflammation and hypercholesteremia in Apolipoprotein E-deficient mice.

Urolithin A (UroA), a dietary phytochemical, is produced by gut bacteria from fruits rich in natural polyphenols ellagitannins (ETs). The efficiency of ETs metabolism to UroA in humans depends on gut microbiota. UroA has shown a variety of pharmacological activities. In this study we investigated the effects of UroA on atherosclerotic lesion development and stability. Apolipoprotein E-deficient (ApoE-/-) mice were fed a high-fat and high-cholesterol diet for 3 months to establish atherosclerosis model. Meanwhile the mice were administered UroA (50 mg·kg-1·d-1, i.g.). We showed that UroA administration significantly decreased diet-induced atherosclerotic lesions in brachiocephalic arteries, macrophage content in plaques, expression of endothelial adhesion molecules, intraplaque hemorrhage and size of necrotic core, while increased the expression of smooth muscle actin and the thickness of fibrous cap, implying features of plaque stabilization. The underlying mechanisms were elucidated using TNF-α-stimulated human endothelial cells. Pretreatment with UroA (10, 25, 50 µM) dose-dependently inhibited TNF-α-induced endothelial cell activation and monocyte adhesion. However, the anti-inflammatory effects of UroA in TNF-α-stimulated human umbilical vein endothelial cells (HUVECs) were independent of NF-κB p65 pathway. We conducted RNA-sequencing profiling analysis to identify the differential expression of genes (DEGs) associated with vascular function, inflammatory responses, cell adhesion and thrombosis in UroA-pretreated HUVECs. Human disease enrichment analysis revealed that the DEGs were significantly correlated with cardiovascular diseases. We demonstrated that UroA pretreatment mitigated endothelial inflammation by promoting NO production and decreasing YAP/TAZ protein expression and TEAD transcriptional activity in TNF-α-stimulated HUVECs. On the other hand, we found that UroA administration modulated the transcription and cleavage of lipogenic transcription factors SREBP1/2 in the liver to ameliorate cholesterol metabolism in ApoE-/- mice. This study provides an experimental basis for new dietary therapeutic option to prevent atherosclerosis.

Resolving length-scale-dependent transient disorder through an ultrafast phase transition.

Material functionality can be strongly determined by structure extending only over nanoscale distances. The pair distribution function presents an opportunity for structural studies beyond idealized crystal models and to investigate structure over varying length scales. Applying this method with ultrafast time resolution has the potential to similarly disrupt the study of structural dynamics and phase transitions. Here we demonstrate such a measurement of CuIr2S4 optically pumped from its low-temperature Ir-dimerized phase. Dimers are optically suppressed without spatial correlation, generating a structure whose level of disorder strongly depends on the length scale. The redevelopment of structural ordering over tens of picoseconds is directly tracked over both space and time as a transient state is approached. This measurement demonstrates the crucial role of local structure and disorder in non-equilibrium processes as well as the feasibility of accessing this information with state-of-the-art XFEL facilities.

Assessing friction and damage of cell monolayers on soft substrates in vitro.

In the area of surgical applications, understanding the interaction between medical device materials and tissue is important since this interaction may cause complications. The interaction often consists of a cell monolayer touching the medical device that can be mimicked in vitro. Prominent examples of this are contact lenses, where epithelial cells interact with the contact lens, or stents and catheters, which are in contact with endothelial cells. To investigate those interactions, in previous studies, expensive microtribometers were used to avoid pressures in the contact area far beyond physiologically relevant levels. Here, we aim to present a new methodology that is cost- and time-efficient, more accessible than those used previously and allows for the application of more realistic pressures, while permitting a quantification of the damage caused to the monolayer. For this, a soft polydimethylsiloxane is employed that better mimics the mechanical properties of blood vessels than materials used in other studies. Furthermore, a technique to account for misalignments within the experiment set-up is presented. This is carried out using the raw spatial and force data recorded by the tribometer and adjusting for misalignments. The methodology is demonstrated using an endothelial cell (human umbilical vein endothelial cells) monolayer.

Ultrafast Optically Induced Perturbation of Oxygen Octahedral Rotations in Multiferroic BiFeO3 Thin Films.

The functional properties of complex oxides, including magnetism and ferroelectricity, are closely linked to subtle structural distortions. Ultrafast optical excitations provide the means to manipulate structural features and ultimately to affect the functional properties of complex oxides with picosecond-scale precision. We report that the lattice expansion of multiferroic BiFeO3 following above-bandgap optical excitation leads to distortion of the oxygen octahedral rotation (OOR) pattern. The continuous coupling between OOR and strain was probed using time-resolved X-ray free-electron laser diffraction with femtosecond time resolution. Density functional theory calculations predict a relationship between the OOR and the elastic strain consistent with the experiment, demonstrating a route to employing this approach in a wider range of systems. Ultrafast control of the functional properties of BiFeO3 thin films is enabled by this approach because the OOR phenomena are related to ferroelectricity, and via the Fe-O-Fe bond angles, the superexchange interaction between Fe atoms.

Benchmarking of X-Ray Fluorescence Microscopy with Ion Beam Implanted Samples Showing Detection Sensitivity of Hundreds of Atoms.

Single impurities in insulators are now often used for quantum sensors and single photon sources, while nanoscale semiconductor doping features are being constructed for electrical contacts in quantum technology devices, implying that new methods for sensitive, non-destructive imaging of single- or few-atom structures are needed. X-ray fluorescence (XRF) can provide nanoscale imaging with chemical specificity, and features comprising as few as 100 000 atoms have been detected without any need for specialized or destructive sample preparation. Presently, the ultimate limits of sensitivity of XRF are unknown - here, gallium dopants in silicon are investigated using a high brilliance, synchrotron source collimated to a small spot. It is demonstrated that with a single-pixel integration time of 1 s, the sensitivity is sufficient to identify a single isolated feature of only 3000 Ga impurities (a mass of just 350 zg). With increased integration (25 s), 650 impurities can be detected. The results are quantified using a calibration sample consisting of precisely controlled numbers of implanted atoms in nanometer-sized structures. The results show that such features can now be mapped quantitatively when calibration samples are used, and suggest that, in the near future, planned upgrades to XRF facilities might achieve single-atom sensitivity.

Kinetic, electrochemical and spectral characterization of bacterial and archaeal rusticyanins; unexpected stability issues and consequences for applications in biotechnology.

Motivated by the ambition to establish an enzyme-driven bioleaching pathway for copper extraction, properties of the Type-1 copper protein rusticyanin from Acidithiobacillus ferrooxidans (AfR) were compared with those from an ancestral form of this enzyme (N0) and an archaeal enzyme identified in Ferroplasma acidiphilum (FaR). While both N0 and FaR show redox potentials similar to that of AfR their electron transport rates were significantly slower. The lack of a correlation between the redox potentials and electron transfer rates indicates that AfR and its associated electron transfer chain evolved to specifically facilitate the efficient conversion of the energy of iron oxidation to ATP formation. In F. acidiphilum this pathway is not as efficient unless it is up-regulated by an as of yet unknown mechanism. In addition, while the electrochemical properties of AfR were consistent with previous data, previously unreported behavior was found leading to a form that is associated with a partially unfolded form of the protein. The cyclic voltammetry (CV) response of AfR immobilized onto an electrode showed limited stability, which may be connected to the presence of the partially unfolded state of this protein. Insights gained in this study may thus inform the engineering of optimized rusticyanin variants for bioleaching processes as well as enzyme-catalyzed solubilization of copper-containing ores such as chalcopyrite.

Nitrate-dependent anaerobic methane oxidation coupled to Fe(III) reduction as a source of ammonium and nitrous oxide.

'Candidatus Methanoperedens nitroreducens' is an archaeal methanotroph with global importance that links carbon and nitrogen cycles and great potential for sustainable operation of wastewater treatment. It has been reported to mediate the anaerobic oxidation of methane through a reverse methanogenesis pathway while reducing nitrate to nitrite. Here, we demonstrate that 'Ca. M. nitroreducens' reduces ferric iron forming ammonium (23.1 %) and nitrous oxide (N2O, 46.5 %) from nitrate. These results are supported with the upregulation of genes coding for proteins responsible for dissimilatory nitrate reduction to ammonium (nrfA), N2O formation (norV, cyt P460), and multiple multiheme c-type cytochromes for ferric iron reduction. Concomitantly, an increase in the N2O-reducing SJA-28 lineage and a decrease in the nitrite-reducing 'Candidatus Methylomirabilis oxyfera' are consistent with the changes in 'Ca. M. nitroreducens' end products. These findings demonstrate the highly flexible physiology of 'Ca. M. nitroreducens' in anaerobic ecosystems with diverse electron acceptor conditions, and further reveals its roles in linking methane oxidation to global biogeochemical cycles. 'Ca. M. nitroreducens' could significantly affect the bioavailability of nitrogen sources as well as the emission of greenhouse gas in natural ecosystems and wastewater treatment plants.

Characterisation of Modular Polyketide Synthases Designed to Make Pentaene Analogues of Amphotericin B.

Glycosylated polyene macrolides are important antifungal agents that are produced by many actinomycete species. Development of new polyenes may deliver improved antibiotics. Here, Streptomyces nodosus was genetically re-programmed to synthesise pentaene analogues of the heptaene amphotericin B. These pentaenes are of interest as surrogate substrates for enzymes catalysing unusual, late-stage biosynthetic modifications. The previous deletion of amphotericin polyketide synthase modules 5 and 6 generated S. nodosus M57, which produces an inactive pentaene. Here, the chain-terminating thioesterase was fused to module 16 to generate strain M57-16TE, in which cycles 5, 6, 17 and 18 are eliminated from the biosynthetic pathway. Another variant of M57 was obtained by replacing modules 15, 16 and 17 with a single 15-17 hybrid module. This gave strain M57-1517, in which cycles 5, 6, 15 and 16 are deleted. M57-16TE and M57-1517 gave reduced pentaene yields. Only M57-1517 delivered its predicted full-length pentaene macrolactone in low amounts. For both mutants, the major pentaenes were intermediates released from modules 10, 11 and 12. Longer pentaene chains were unstable. The novel pentaenes were not glycosylated and were not active against Candida albicans. However, random mutagenesis and screening may yet deliver new antifungal producers from the M57-16TE and M57-1517 strains.

Biosynthesis of a new skyllamycin in Streptomyces nodosus: a cytochrome P450 forms an epoxide in the cinnamoyl chain.

Activation of a silent gene cluster in Streptomyces nodosus leads to synthesis of a cinnamoyl-containing non-ribosomal peptide (CCNP) that is related to skyllamycins. This novel CCNP was isolated and its structure was interrogated using mass spectrometry and nuclear magnetic resonance spectroscopy. The isolated compound is an oxidised skyllamycin A in which an additional oxygen atom is incorporated in the cinnamoyl side-chain in the form of an epoxide. The gene for the epoxide-forming cytochrome P450 was identified by targeted disruption. The enzyme was overproduced in Escherichia coli and a 1.43 Å high-resolution crystal structure was determined. This is the first crystal structure for a P450 that forms an epoxide in a substituted cinnamoyl chain of a lipopeptide. These results confirm the proposed functions of P450s encoded by biosynthetic gene clusters for other epoxidized CCNPs and will assist investigation of how epoxide stereochemistry is determined in these natural products.

Temperature, pH, and oxygen availability contributed to the functional differentiation of ancient Nitrososphaeria.

Ammonia-oxidizing Nitrososphaeria are among the most abundant archaea on Earth and have profound impacts on the biogeochemical cycles of carbon and nitrogen. In contrast to these well-studied ammonia-oxidizing archaea (AOA), deep-branching non-AOA within this class remain poorly characterized because of a low number of genome representatives. Here, we reconstructed 128 Nitrososphaeria metagenome-assembled genomes from acid mine drainage and hot spring sediment metagenomes. Comparative genomics revealed that extant non-AOA are functionally diverse, with capacity for carbon fixation, carbon monoxide oxidation, methanogenesis, and respiratory pathways including oxygen, nitrate, sulfur, or sulfate, as potential terminal electron acceptors. Despite their diverse anaerobic pathways, evolutionary history inference suggested that the common ancestor of Nitrososphaeria was likely an aerobic thermophile. We further surmise that the functional differentiation of Nitrososphaeria was primarily shaped by oxygen, pH, and temperature, with the acquisition of pathways for carbon, nitrogen, and sulfur metabolism. Our study provides a more holistic and less biased understanding of the diversity, ecology, and deep evolution of the globally abundant Nitrososphaeria.

NAFLD and NASH: etiology, targets and emerging therapies.

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) pose a significant threat to human health and cause a tremendous socioeconomic burden. Currently, the molecular mechanisms of NAFLD and NASH remain incompletely understood, and no effective pharmacotherapies have been approved. In the past five years, significant advances have been achieved in our understanding of the pathomechanisms and potential pharmacotherapies of NAFLD and NASH. Research advances include the investigation of the effects of the fibroblast growth factor 21 (FGF21) analog pegozafermin and the thyroid hormone receptor-ß (THRß) agonist resmetriom on hepatic fat content, NASH resolution and/or fibrosis regression. Future directions of NAFLD and NASH research (including combination therapy, organoids and humanized mouse models) are also discussed in this state-of-the-art review.

Giant electric field-induced second harmonic generation in polar skyrmions.

Electric field-induced second harmonic generation allows electrically controlling nonlinear light-matter interactions crucial for emerging integrated photonics applications. Despite its wide presence in materials, the figures-of-merit of electric field-induced second harmonic generation are yet to be elevated to enable novel device functionalities. Here, we show that the polar skyrmions, a topological phase spontaneously formed in PbTiO3/SrTiO3 ferroelectric superlattices, exhibit a high comprehensive electric field-induced second harmonic generation performance. The second-order nonlinear susceptibility and modulation depth, measured under non-resonant 800 nm excitation, reach ~54.2 pm V-1 and ~664% V-1, respectively, and high response bandwidth (higher than 10 MHz), wide operating temperature range (up to ~400 K) and good fatigue resistance (>1010 cycles) are also demonstrated. Through combined in-situ experiments and phase-field simulations, we establish the microscopic links between the exotic polarization configuration and field-induced transition paths of the skyrmions and their electric field-induced second harmonic generation response. Our study not only presents a highly competitive thin-film material ready for constructing on-chip devices, but opens up new avenues of utilizing topological polar structures in the fields of photonics and optoelectronics.