44 research outputs found

    Rosuvastatin reduces neointima formation in a rat model of balloon injury

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Processes of restenosis, following arterial injury, are complex involving different cell types producing various cytokines and enzymes. Among those enzymes, smooth muscle cell-derived matrix metalloproteinases (MMPs) are thought to take part in cell migration, degrading of extracellular matrix, and neointima formation. MMP-9, also known as gelatinase B, is expressed immediately after vascular injury and its expression and activity can be inhibited by statins. Using an established in vivo model of vascular injury, we investigated the effect of the HMG-CoA reductase inhibitor rosuvastatin on MMP-9 expression and neointima formation.</p> <p>Materials and methods</p> <p>14-week old male Sprague Dawley rats underwent balloon injury of the common carotid artery. Half of the animals received rosuvastatin (20 mg/kg body weight/day) via oral gavage, beginning 3 days prior to injury. Gelatinase activity and neointima formation were analyzed 3 days and 14 days after balloon injury, respectively. 14 days after vascular injury, proliferative activity was assessed by staining for Ki67.</p> <p>Results</p> <p>After 14 days, animals in the rosuvastatin group showed a decrease in total neointima formation (0.194 ± 0.01 mm<sup>2 </sup>versus 0.124 ± 0.02 mm<sup>2</sup>, p < 0.05) as well as a reduced intima/media ratio (1.26 ± 0.1 versus 0.75 ± 0.09, p < 0.05). Balloon injury resulted in increased activity of MMP-9 3 days after intervention for both rosuvastatin treated animals and controls with no significant difference observed between the groups. There was a trend towards a reduction in the number of Ki67-positive cells 14 days after injury.</p> <p>Conclusions</p> <p>Rosuvastatin attenuates neointima formation without affecting early MMP-9 activity in a rat model of vascular injury.</p

    Grazing intensities and poultry litter fertilization levels on corn and black oat yield

    Get PDF
    The objective of this work was to assess the effect of poultry litter fertilization levels on corn and black oat yield using different grazing intensities, poultry litter levels (mixture of manure and bedding material) and a chemical fertilization level. The experimental design was a randomized complete block in a split-plot arrangement with four replicates. Black oat + ryegrass grazing intensities, characterized by different pasture sward management, with animal entrance at 25, 30 and 35-cm heights and exit at 5.0, 10 and 15-cm heights, were established at the main plots. After the grazing period, corn was grown at the subplots with four levels of poultry litter (0, 4,953, 9,907 and 14,860 kg ha-1), aiming to supply 0, 100, 200 and 300 kg ha-1 of nitrogen, and a treatment with chemical fertilizer, according to soil analysis. Grazing intensities had no effect on corn yield. Corn yield was 7,493, 8,458, 9,188, 10,247 and 11,028 kg ha-1, respectively, for the treatments without and with 4,953, 9,907 and 14,860 kg ha-1 of poultry litter, and the treatment with chemical fertilization. Poultry litter levels have a residual effect on the production of black oat grown in succession to corn

    Combined treatment with olmesartan medoxomil and amlodipine besylate attenuates atherosclerotic lesion progression in a model of&nbsp;advanced atherosclerosis

    No full text
    Philipp Sievers,1 Lorenz Uhlmann,2 Sevil Korkmaz-Ic&ouml;z,3 Christian Fastner,1 Florian Bea,1 Erwin Blessing,1 Hugo A Katus,1 Michael R Preusch11Department of Internal Medicine III, 2Institute of Medical Biometry and&nbsp;Informatics, 3Department of&nbsp;Cardiac Surgery, University of Heidelberg, Heidelberg, GermanyIntroduction: Besides their blood pressure-lowering effects, olmesartan medoxomil and amlodipine besylate exhibit additional anti-inflammatory mechanisms in atherosclerosic disease. Most of the studies investigating the effects of atherosclerosis focused on early atherosclerotic lesions, whereas lesions in human disease, at the time when medical treatment is started, are already well established. Therefore, we set up a model of advanced atherosclerosis and investigated the effects of olmesartan medoxomil, amlodipine besylate, and the combination of both on atherosclerotic lesion size and lesion composition.Materials and methods: Olmesartan medoxomil (1 mg/kg/day), amlodipine besylate (1.5 mg/kg/day), and the combination of both was added to chow and was fed to apolipoprotein E-deficient (ApoE-/-) mice at 25 weeks of age. Mice were sacrificed after 25 weeks of drug administration and perfused with formalin. Innominate arteries were dissected out and paraffin embedded. Serial sections were generated, and lesion sizes and their composition &ndash; such as minimal thickness of the fibrous cap, size of the necrotic core, and presence of calcification &ndash; were analyzed. Electrophoretic mobility shift assays were used to detect DNA-binding activity of the transcription factor nuclear factor-kappa B (NF-&kappa;B) in aortic tissue.Results: Treatment with the combination of olmesartan medoxomil and amlodipine besylate led to a significant reduction in atherosclerotic lesion size in ApoE-/- mice (olmesartan medoxomil/amlodipine besylate: 122,277&plusmn;6,795 &micro;m2, number [n]=14; versus control: 177,502&plusmn;10,814 &micro;m2, n=9; P&lt;0.001). Treatment with amlodipine besylate (n=5) alone did not reach significance. However, a trend toward a decrease in lesion size in the amlodipine besylate-treated animals could be observed. In the histological analysis of atherosclerotic lesion composition, significantly thicker fibrous caps were found in treatment with amlodipine besylate (amlodipine: 5.12&plusmn;0.26 &micro;m, n=6; versus control: 3.98&plusmn;0.18 &micro;m, n=10; P&lt;0.01). Furthermore, all sections revealed morphological signs of calcification, but no difference could be detected. Treatment with the combination of olmesartan medoxomil and amlodipine besylate showed no effect on lesion composition. Electrophoretic mobility shift assays of nuclear extracts demonstrated reduced activity of the transcription factor NF-&kappa;B when treated with olmesartan medoxomil, amlodipine besylate, or their combination, as compared to controls.Conclusion: Combined treatment with olmesartan medoxomil and amlodipine besylate attenuated atherosclerotic lesion progression, possibly due to anti-inflammatory mechanisms. Our data support the hypothesis that even in advanced atherosclerosis anti-inflammatory treatment, using angiotensin II type 1 receptor blockers and calcium channel antagonists of the dihydropyridine type can attenuate atherosclerotic lesion progression.Keywords: advanced atherosclerosis, AT1 receptor blocker, calcium channel antagonist, inflammation, NF-&kappa;B, Apo

    Dabigatran etexilate retards the initiation and progression of atherosclerotic lesions and inhibits the expression of oncostatin M in apolipoprotein E-deficient mice

    No full text
    Michael R Preusch,1,2 Nicholas Ieronimakis,1 Errol S Wijelath,3 Sara Cabbage,1 Jerry Ricks,1 Florian Bea,2 Morayma Reyes,1 Joanne van Ryn,4 Michael E Rosenfeld1,5 1Department of Pathology, University of Washington, Seattle, WA, USA; 2Department of Internal Medicine, University of Heidelberg, Heidelberg, Germany; 3Department of Surgery, University of Washington, Seattle, WA, USA; 4Department of CardioMetabolic Disease Research, Boehringer Ingelheim Pharma GmbH &amp; Co KG, Biberach, Germany; 5Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA Objective: Thrombin has multiple proatherogenic effects including platelet activation and the induction of inflammatory processes. Recently, the cytokine oncostatin M has been shown to have proinflammatory effects. This study was designed to investigate the effects of thrombin inhibition on the initiation and progression of atherosclerosis and on the expression of oncostatin M. Methods: Apolipoprotein E-deficient mice at different ages were fed the thrombin inhibitor dabigatran etexilate. The mean lesion area was measured in the aortic sinus and in the innominate artery. CD45-positive cells within the aortic tissue were measured by flow cytometry. Oncostatin M expression was measured in the tissue sections by immunocytochemistry. Results: Treatment with dabigatran etexilate resulted in a significant reduction of the mean area of atherosclerotic lesions in the aortic sinus in both the young mice (11,176&plusmn;1,500 &micro;m2 (control) versus 3,822&plusmn;836 &micro;m2 (dabigatran etexilate), P&lt;0.05) and selectively in the older mice at 28 weeks (234,099&plusmn;13,500 &micro;m2 (control) versus 175,226&plusmn;16,132 &micro;m2 (dabigatran etexilate), P&lt;0.05). There were also fewer CD45-positive cells within the aortas of the dabigatran-treated mice and enhanced NO production in endothelial cells pretreated with dabigatran. In addition, the expression of oncostatin M was reduced in the lesions of dabigatran etexilate-treated mice. Conclusion: Inhibition of thrombin by dabigatran retards the development of early lesions and the progression of some established lesions in ApoE-/- mice. It improves endothelial function and retards macrophage accumulation within the vascular wall. Dabigatran also inhibits the expression of oncostatin M, and this suggests that oncostatin M may play a role in the initiation and progression of atherosclerosis. Keywords: macrophages, thrombin, coagulation, inflammatio

    Ticagrelor promotes atherosclerotic plaque stability in a mouse model of advanced atherosclerosis

    No full text
    Michael R Preusch,1 Jonas Rusnak,1 Kathrin Staudacher,2 Carolin Mogler,3 Lorenz Uhlmann,4 Philipp Sievers,1 Florian Bea,1 Hugo A Katus,1 Erwin Blessing,1 Ingo Staudacher1 1Department of Internal Medicine III, 2Department of Neonatology, 3Department of Pathology, 4Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany Objective: There is increasing evidence supporting the role of platelets in atherosclerotic vascular disease. The G-protein-coupled receptor P2Y12 is a central mediator of platelet activation and aggregation but has also been linked to platelet-independent vascular disease. Ticagrelor is an oral P2Y12 antagonist that is used as a standard treatment in patients after acute myocardial infarction. However, the effects of ticagrelor on advanced atherosclerosis have not been investigated.Materials and methods: Twenty-week-old apolipoprotein-E-deficient mice received standard chow or standard chow supplemented with 0.15% ticagrelor (approximately 270 mg/kg/day) for 25 weeks. The lesion area was evaluated in the aortic sinus by Movat&rsquo;s pentachrome staining and lesion composition, thickness of the fibrous cap, and size of the necrotic core evaluated by morphometry. RAW 264.7 macrophages were serum starved and treated with ticagrelor in vitro for the detection and quantification of apoptosis. In addition, oxLDL uptake in RAW 264.7 macrophages was evaluated.Results: A trend toward the reduction of total lesion size was detected. However, data did not reach the levels of significance (control, n=11, 565,881 &micro;m2 [interquartile range {IQR} 454,778&ndash;603,925 &micro;m2] versus ticagrelor, n=13, 462,595 &micro;m2 [IQR 379,740&ndash;546,037 &micro;m2]; P=0.1). A&nbsp;significant reduction in the relative area of the necrotic core (control, n=11, 0.46 [IQR 0.4&ndash;0.51] versus ticagrelor, n=13, 0.34 [IQR 0.31&ndash;0.39]; P=0.008), and a significant increase in fibrous caps thickness (control, n=11, 3.7 &micro;m [IQR 3.4&ndash;4.2 &micro;m] versus ticagrelor, n=13, 4.7 [IQR 4.3&ndash;5.5 &micro;m], P=0.04) were seen in ticagrelor-treated mice. In vitro studies demonstrated a reduction in apoptotic RAW 264.7 macrophages (control 0.07&plusmn;0.03 versus ticagrelor 0.03&plusmn;0.03; P=0.0002) when incubated with ticagrelor. Uptake of oxLDL in RAW 264.7 was significantly reduced when treated with ticagrelor (control 9.2 [IQR 5.3&ndash;12.9] versus ticagrelor 6.4 [IQR 2.5&ndash;9.5], P=0.02).Conclusion: The present study demonstrates for the first time a plaque-stabilizing effect of ticagrelor in a model of advanced vascular disease, potentially induced by a reduction of oxLDL uptake or an inhibition of apoptosis as seen in vitro. Keywords: atherosclerosis, inflammation, apoptosis, ticagrelor, platelets, P2Y12, oxLDL, apoE mous

    Critical Role of Macrophages in Glucocorticoid Driven Vascular Calcification in a Mouse-Model of Atherosclerosis

    No full text
    OBJECTIVE: Macrophage-derived products are known to play a crucial role during atherogenesis and vascular calcification. Glucocorticoids (GC) are important modulators of immune cell functions, but their specific effects on macrophages behavior during plaque formation are not defined. The present study was therefore designed to investigate the effects of macrophage-specific deletion of the glucocorticoid receptor (GR(LysMCre)) on atherogenesis and vascular calcification in a hyperlipidemic mouse-model. METHODS AND RESULTS: Bone marrow was isolated from GR(LysMCre) mice and wild-type controls (GR(flox)) and subsequently transplanted into lethally irradiated LDL-receptor-deficient mice. Animals were fed a Western-type diet for 15 or 24 weeks, and atherosclerotic lesions within the aortic sinus were evaluated. At both time points, no significant difference in serum lipid and corticosterone concentrations, atherosclerotic lesion size and macrophage-content within the lesions could be observed. However, GR(LysMCre) mice showed less calcification as well as a significant reduction of RANKL, BMP2, and Msx2 expression within the vasculature. In vitro studies using conditioned media from macrophages which had been stimulated with dexamethasone demonstrated a dose-dependent increase in calcium deposition by vascular smooth muscle cells. CONCLUSIONS: This study demonstrates that macrophage-specific glucocorticoid receptor inactivation reduces vascular calcification without affecting atherosclerotic lesion size in LDL receptor-deficient mice The first two authors contributed equally to this stud

    Non-Invasive Ventilation as a Therapy Option for Acute Exacerbations of Chronic Obstructive Pulmonary Disease and Acute Cardiopulmonary Oedema in Emergency Medical Services

    No full text
    In this observational prospective multicenter study conducted between October 2016 and October 2018, we tested the hypothesis that the use of prehospital non-invasive ventilation (phNIV) to treat patients with acute respiratory insufficiency (ARI) caused by severe acute exacerbations of chronic obstructive pulmonary disease (AECOPD) and acute cardiopulmonary oedema (ACPE) is effective, time-efficient and safe. The data were collected at four different physician response units and three admitting hospitals in a German EMS system. Patients with respiratory failure due to acute exacerbation of chronic obstructive pulmonary disease and acute cardiopulmonary oedema were enrolled. A total of 545 patients were eligible for the final analysis. Patients were treated with oxygen supplementation, non-invasive ventilation or invasive mechanical ventilation. The primary outcomes were defined as changes in the clinical parameters and the in-hospital course. The secondary outcomes included time efficiency, peri-interventional complications, treatment failure rate, and side-effects. Oxygenation under phNIV improved equally to endotracheal intubation (ETI), and more effectively in comparison to standard oxygen therapy (SOT) (paO2 SOT vs. non-invasive ventilation (NIV) vs. ETI: 82 mmHg vs. 125 mmHg vs. 135 mmHg, p-value SOT vs. NIV < 0.0001). In a matched subgroup analysis phNIV was accompanied by a reduced time of mechanical ventilation (phNIV: 1.8 d vs. ETI: 4.2 d) and a shortened length of stay at the intensive care unit (3.4 d vs. 5.8 d). The data support the hypothesis that the treatment of severe AECOPD/ACPE-induced ARI using prehospital NIV is effective, time efficient and safe. Compared to ETI, a matched comparison supports the hypothesis that prehospital implementation of NIV may provide benefits for an in-hospital course
    corecore