86 research outputs found

    Arterial stiffness is associated with adipokine dysregulation in non-hypertensive obese mice

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    This is the peer reviewed version of the following article: Vascular Pharmacology 77 (2016): 38-47, which has been published in final form at http://dx.doi.org/10.1016/j.vph.2015.05.012The aim of this study was to characterize alterations in vascular structure and mechanics in murine mesenteric arteries from obese non-hypertensive mice, as well as their relationship with adipokines. Four-week old C57BL/6J male mice were assigned either to a control (C, 10% kcal from fat) or a high-fat diet (HFD, 45% kcal from fat) for 32 weeks. HFD animals weighed 30% more than controls (p < 0.001), exhibited similar blood pressure, increased leptin, insulin and superoxide anion (O2radical dot−) levels, and reduced adiponectin levels and nitric oxide (NO) bioavailability. Arterial structure showed an outward remodeling with an increase in total number of both adventitial and smooth muscle cells in HFD. Moreover, HFD mice exhibited an increased arterial stiffness assessed by β-values (C = 2.4 ± 0.5 vs HFD = 5.3 ± 0.8; p < 0.05) and aortic pulse wave velocity (PWV, C = 3.4 ± 0.1 vs HFD = 3.9 ± 0.1; p < 0.05). β-Values and PWV positively correlated with leptin, insulin or O2radical dot− levels, whereas they negatively correlated with adiponectin levels and NO bioavailability (p < 0.01). A reduction in fenestrae number together with an increase in type-I collagen amount (p < 0.05) were observed in HFD. These data demonstrate that HFD accounts for the development of vascular remodeling and arterial stiffness associated with adipokine dysregulation and oxidative stress, independently of hypertension developmentThis work was supported by grants from Ministerio de Ciencia e Investigación (BFU2011-25303), Ministerio de Economía y Competitividad (SAF2009-09714, SAF2011-25303, BFU2012-35353), Grupos Universidad Complutense de Madrid (UCM; GR-921641), Fundación Universitaria CEU-San Pablo, Fundación Mutua Madrileña and Sociedad para el Estudio de la Salud Cardiometabólica (SESCAMET). MGO is recipient of a Ministerio de Educación y Ciencia fellowshi

    Imbalance between pro and anti-oxidant mechanisms in perivascular adipose tissue aggravates long-term high-fat diet-derived endothelial dysfunction

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    Background: The hypothesis of this study is that long-term high-fat diets (HFD) induce perivascular adipose tissue (PVAT) dysfunction characterized by a redox imbalance, which might contribute to aggravate endothelial dysfunction in obesity. Methods and Results: C57BL/6J mice were fed either control or HFD (45% kcal from fat) for 32 weeks. Body weight, lumbar and mesenteric adipose tissue weights were significantly higher in HFD animals compared to controls. The anticontractile effect of PVAT in mesenteric arteries (MA) was lost after 32 week HFD and mesenteric endothelial-dependent relaxation was significantly impaired in presence of PVAT in HFD mice (Emax = 71.0±5.1 vs Emax = 58.5±4.2, p<0.001). The inhibitory effect of L-NAME on Ach-induced relaxation was less intense in the HFD group compared with controls suggesting a reduction of endothelial NO availability. Expression of eNOS and NO bioavailability were reduced in MA and almost undetectable in mesenteric PVAT of the HFD group. Superoxide levels and NOX activity were higher in PVAT of HFD mice. Apocynin only reduced contractile responses to NA in HFD animals. Expression of ec-SOD and total SOD activity were significantly reduced in PVAT of HFD mice. No changes were observed in Mn-SOD, Cu/Zn-SOD or catalase. The ratio [GSSG]/([GSH]+[GSSG]) was 2-fold higher in the mesenteric PVAT from HFD animals compared to controls. Conclusions: We suggest that the imbalance between pro-oxidant (NOX, superoxide anions, hydrogen peroxide) and antioxidant (eNOS, NO, ecSOD, GSSG) mechanisms in PVAT after long-term HFD might contribute to the aggravation of endothelial dysfunctionThis work was supported by grants from Ministerio de Ciencia e Investigación (BFU2011-25303), Ministerio de Economía y Competitividad (SAF2009- 09714, SAF2011-25303, BFU2012-35353), Grupos Universidad Complutense de Madrid (UCM; GR-921641), Fundación Universitaria San Pablo-CEU, Fundación Mutua Madrileña and Sociedad para el Estudio de la Salud Cardiometabólica (SESCAMET). MGO and CFG-P are supported by Ministerio de Educación y Cienci

    Morphology and characterisation of the relict facies on the internal continental shelf in the Gulf of Cadiz, between Ayamonte and Huelva (southern Iberian Peninsula)

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    The objectives of the present paper are the determination of the morphologic characteristics of the superficial Quaternary relict facies on the internal continental shelf in the Gulf of Cadiz, between Ayamonte and Huelva (southern Spain), their characterisation, and their evolution in the final phases of the last eustatic hemicycle. The study area extends from the mouth of the Guadiana River to the mouth of the Tinto-Odiel River, and from the 6 m isobath to the 56 m isobath. High-resolution seismic profiles (3.5 kHz and Geopulse, 175 J), sonographic profiles (SSS, 100 kHz), and bathymetric profiles (Echotrac sounder) were used in this study. Sediment samples were obtained using Van Veen and Shipek drags. Bathymetric, physiographic, lithologic and morphologic analyses were performed to determine the superficial sediment distribution, relict facies distribution, and thickness of the unconsolidated sediment cover. Analysis of the data obtained indicated that the relict facies beaches and coastal barriers associated with coastal spits located in the ancient outlets of the rivers. Relict facies were grouped into well-differentiated depths, indicating that their position on the continental shelf is influenced by the still-stands and the periods of rapid sea-level changes. The nature of the outcropping relict facies shows that their final configuration can be related to the shelf construction processes, as well as to the most important Holocene transgressive phases.Los objetivos de este trabajo son la determinación de las características morfológicas, la caracterización de las facies relictas cuaternarias superficiales y el estudio de su evolución con relación a las fases finales del último hemiciclo eustático en la plataforma continental interna del golfo de Cádiz, entre Ayamonte y Huelva. El área de estudio abarca desde la desembocadura del río Guadiana hasta la del río Tinto-Odiel y desde los 6 m hasta 56 m de profundidad. Se utilizó gran cantidad de material geofísico, en el que se encuentran perfiles sísmicos de alta resolución (3.5 kHz y Geopulse, 175 J), perfiles sonográficos y perfiles batimétricos, además de muestras de sedimentos obtenidas con dragas Van Veen y Shipek. Con esta información se han realizado análisis batimétricos, fisiográficos, litológicos y morfológicos, además de determinar la distribución de los sedimentos superficiales y de las facies relictas y de cuantificar la potencia de la cobertera sedimentaria. Con todos los datos obtenidos se ha determinado que las facies relictas son interpretadas como playas y cordones litorales asociados a flechas litorales situadas en las antiguas desembocaduras de los ríos. Las formas descritas están agrupadas en zonaciones batimétricas bien diferenciadas, lo que indica que su posición en la plataforma continental está influida por las paradas y etapas de movimiento rápido del nivel del mar. Las características de las facies relictas aflorantes indican que su configuración final puede estar relacionada con los procesos de edificación de la plataforma a partir de las mayores fases transgresivas holocenas.Instituto Español de Oceanografí

    A relict oasis of living deep-sea mussels Bathymodiolus and microbial-mediated seep carbonates at newly-discovered active cold seeps in the Gulf of Cádiz, NE Atlantic Ocean

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    Extensive beds of the deep-sea mussel Bathymodiolus mauritanicus (currently also known as Gigantidas mauritanicus) linked to active cold seeps related to fissure-like activity on Al Gacel mud volcano, Gulf of Cádiz, were filmed and sampled for the first time during the oceanographic expedition SUBVENT-2 aboard R/V Sarmiento de Gamboa. Al Gacel mud volcano is one of up to 80 fluid venting submarine structures (mud volcanoes and mud volcano/diapir complexes) identified in the Gulf of Cádiz as result of explosive venting of hydrocarbon-enriched fluids sourced from deep seated reservoirs. This mud volcano is a cone-shaped edifice, 107 m high, 944 m in diameter constituted by mud breccias and, partially covered by pavements of seep carbonates. Extensive beds of this deep-sea mussel were detected at the northern flank at 810–815 m water depth associated with bacterial mats around intermittent buoyant vertical bubble methane plumes. High methane concentrations were measured in the water column above living mussel beds. Other chemosymbiotic species (Siboglinum sp., Solemya elarraichensis, Isorropodon sp., Thyasira vulcolutre and Lucinoma asapheus) were also found in different parts of Al Gacel mud volcano. Al Gacel mud volcano may currently represent one of the most active mud volcanoes in the Gulf of Cádiz, delivering significant amounts of thermogenic hydrocarbon fluids which contribute to foster the extensive chemosynthesis-based communities detected. This finding is of paramount importance for linking extremophile bivalve populations along the North Atlantic, including cold seeps of the Gulf of México, hydrothermal vents of the Mid-Atlantic Ridge and now, detailed documented at the Gulf of Cádiz.Versión del edito

    Anticontractile Effect of Perivascular Adipose Tissue and Leptin are Reduced in Hypertension

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    Leptin causes vasodilatation both by endothelium-dependent and -independent mechanisms. Leptin is synthesized by perivascular adipose tissue (PVAT). The hypothesis of this study is that a decrease of leptin production in PVAT of spontaneously hypertensive rats (SHR) might contribute to a diminished paracrine anticontractile effect of the hormone. We have determined in aorta from Wistar-Kyoto (WKY) and SHR (i) leptin mRNA and protein levels in PVAT, (ii) the effect of leptin and PVAT on contractile responses, and (iii) leptin-induced relaxation and nitric oxide (NO) production. Leptin mRNA and protein expression were significantly lower in PVAT from SHR. Concentration-response curves to angiotensin II were significantly blunted in presence of PVAT as well as by exogenous leptin (10−9 M) only in WKY. This anticontractile effect was endothelium-dependent. Vasodilatation induced by leptin was smaller in SHR than in WKY, and was also endothelium-dependent. Moreover, release of endothelial NO in response to acute leptin was higher in WKY compared to SHR, but completely abolished in the absence of endothelium. In conclusion, the reduced anticontractile effect of PVAT in SHR might be attributed to a reduced PVAT-derived leptin and to an abrogated effect of leptin on endothelial NO release probably due to an impaired activation of endothelial NO synthase

    Micro-morphologies, habitats and associated biodiversity in a fluid venting submarine structure using ROV underwater images: Mercator mud volcano (Gulf of Cádiz)

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    Mercator mud volcano has been explored by direct visual observations using a ROV at 350 to 370 m depth. Underwater images, taken mainly at the summit, have allowed characterizing the fluid venting environment, where different microforms, habitats and associated biota, with typical seepage components have been identified. Chemosynthetic bacterial communities were detected and sampled at the northeastern side of the summit at 350 m, next to pockmark-like depressions with diameters ranging 1 to 3 m, bioturbation marks, sediment mounds and authigenic carbonates of different sizes (0.1-5m length). Chemosynthesis-based communities were mainly composed by bacterial mats (patch diameter 10-30 cm), however some remains of cold seep chemosymbiotic bivalves (Lucinoma asapheus) were also found on the sediment. Habitat types at Mercator MV are influenced by oceanographic and sedimentation processes deposition and favouring fauna colonizing diverse substrate types, such as large sponges on slabs and sea-pens and annelids on soft bottoms

    Normal vector analysis from GNSS-GPS data applied to Deception volcano surface deformation

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    Surface deformation parameters and its use in volcano monitoring have evolved from classical geodetic procedures up to those based on Global Navigation Satellite Systems (GNSS), in particular the most widely used and known Global Positioning System (GPS), profiting from the automated data processing, positioning precision and rates, as well as the large storage capacity and low power consumption of its equipments. These features have enabled the permanent GNSSGPS data acquisition to ensure the continuous monitoring of geodetic benchmarks for the evaluation of surface deformation in active tectonic or volcanic areas. In Deception Island (Antarctica), a normal vector analysis is being used to give surface deformation based on three permanently observed GNSSGPS benchmarks. Due to data availability, both in the past and for near real-time use, all benchmarks used are inside the monitored volcanic area, although the reference is away from thermal springs and/or fumaroles, unlike the other two. The time variation of slope distances to the reference benchmark and of the magnitude and inclination of the normal vector to the triangle defined by the reference benchmark and any other two, provides the spatial deformation in the volcanic area covered. The normal vector variation in magnitude gives information on compression or expansion, here called spatial dilatometer, while the changes in inclination gives information on relative uplift or subsidence, here called spatial inclinometer. In geodesy, the triangle is a basic geometric unit and the areal strain is commonly applied in tectonics and volcanism. The normal vector analysis conjugates both, benefiting from the method's precision, simplicity and possibility to model the surface using several triangles. The proposed method was applied to GNSSGPS data collected every austral summer between 20012002 and 20092010 in Deception Island. The results evidence that Deception Island acts as a strain marker in the Bransfield Basin volcano-tectonic setting.Spanish Ministry of Education and Science as part of the National Antarctic Program; Recognition and fast evaluation of volcanic activity on Deception Island (GEODESY) [ANT1999-1430-E/HESP]; Geodetic Studies on Deception Island: deformation models, geoid determination and Scientific Information System [REN2000-0551-C03-01/ANT]; Acquisition of scientific software for GPS data processing [REN2000-2690-E]; Geodetic Control of the volcanic activity of Deception Island [CGL2004-21547-E/ANT]; Update of the Spanish Cartography for Deception Island [CGL2004-20408-E/ANT]; Volcanotectonic activity on Deception Island: geodetic, geophysical investigations and Remote Sensing on Deception Island and its surroundings [CGLl2005-07589-c03-01/ANT]; Geodetic and Geothermal Researches, Time Serial Analysis and Volcanic Innovation in Antarctica (South Shetland Islands and Antarctic Peninsula (GEOTINANT) [CTM2009-07251/ANT]info:eu-repo/semantics/publishedVersio

    Differential Deleterious Impact of Highly Saturated Versus Monounsaturated Fat Intake on Vascular Function, Structure, and Mechanics in Mice

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    Vegetable oils such as palm oil (enriched in saturated fatty acids, SFA) and high-oleic-acid sunflower oil (HOSO, containing mainly monounsaturated fatty acids, MUFA) have emerged as the most common replacements for trans-fats in the food industry. The aim of this study is to analyze the impact of SFA and MUFA-enriched high-fat (HF) diets on endothelial function, vascular remodeling, and arterial stiffness compared to commercial HF diets. Five-week-old male C57BL6J mice were fed a standard (SD), a HF diet enriched with SFA (saturated oil-enriched Food, SOLF), a HF diet enriched with MUFA (unsaturated oil-enriched Food, UOLF), or a commercial HF diet for 8 weeks. Vascular function was analyzed in the thoracic aorta. Structural and mechanical parameters were assessed in mesenteric arteries by pressure myography. SOLF, UOLF, and HF diet reduced contractile responses to phenylephrine and induced endothelial dysfunction in the thoracic aorta. A significant increase in the β-index, and thus in arterial stiffness, was also detected in mesenteric arteries from the three HF groups, due to enhanced deposition of collagen in the vascular wall. SOLF also induced hypotrophic inward remodeling. In conclusion, these data demonstrate a deleterious effect of HF feeding on obesity-related vascular alterations that is exacerbated by SFA
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