280 resultados para CARDIAC INFLAMMATION
Resumo:
An Automated Interpulse Duration Assessment system (AIDA) is described which permits detection of irregularities in cardiac rhythms in selected invertebrates. The sensitivity of AIDA was demonstrated by its ability to detect handling stress in mussels (Mytilus edulis) that was not evident when measuring heart rate alone. Changes in cardiac activity patterns of crabs (Carcinus maenas) held in the laboratory for up to 10 wk was also examined using the new technique. The frequency distribution of interpulse duration changed significantly as the nutritional state changed. Potential applications of the AIDA system are discussed.
Resumo:
Previous studies have shown that following whole-body irradiation bone marrow (BM)-derived cells can migrate into the central nervous system, including the retina, to give rise to microglia-like cells. The detailed mechanism, however, remains elusive. We show in this study that a single-dose whole-body ?-ray irradiation (8 Gy) induced subclinical damage (i.e., DNA damage) in the neuronal retina, which is accompanied by a low-grade chronic inflammation, para-inflammation, characterized by upregulated expression of chemokines (CCL2, CXCL12, and CX3CL1) and complement components (C4 and CFH), and microglial activation. The upregulation of chemokines CCL2 and CXCL12 and complement C4 lasted for more than 160 days, whereas the expression of CX3CL1 and CFH was upregulated for 2 weeks. Both resident microglia and BM-derived phagocytes displayed mild activation in the neuronal retina following irradiation. When BM cells from CX3CR1gfp/+ mice or CX3CR1gfp/gfp mice were transplanted to wild-type C57BL/6 mice, more than 90% of resident CD11b+ cells were replaced by donor-derived GFP+ cells after 6 months. However, when transplanting CX3CR1gfp/+ BM cells into CCL2-deficient mice, only 20% of retinal CD11b+ cells were replaced by donor-derived cells at 6 month. Our results suggest that the neuronal retina suffers from a chronic stress following whole-body irradiation, and a para-inflammatory response is initiated, presumably to rectify the insults and maintain homeostasis. The recruitment of BM-derived myeloid cells is a part of the para-inflammatory response and is CCL2 but not CX3CL1 dependent. © 2012 Wiley Periodicals, Inc.
Resumo:
Maternal diabetes mellitus is associated with increased teratogenesis, which can occur in pregestational type 1 and type 2 diabetes. Cardiac defects and with neural tube defects are the most common malformations observed in fetuses of pregestational diabetic mothers. The exact mechanism by which diabetes exerts its teratogenic effects and induces embryonic malformations is unclear. Whereas the sequelae of maternal pregestational diabetes, such as modulating insulin levels, altered fat levels, and increased reactive oxygen species, may play a role in fetal damage during diabetic pregnancy, hyperglycemia is thought to be the primary teratogen, causing particularly adverse effects on cardiovascular development. Fetal cardiac defects are associated with raised maternal glycosylated hemoglobin levels and are up to five times more likely in infants of mothers with pregestational diabetes compared with those without diabetes. The resulting anomalies are varied and include transposition of the great arteries, mitral and pulmonary atresia, double outlet of the right ventricle, tetralogy of Fallot, and fetal cardiomyopathy.
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Left ventricular pressure overload in response to aortic banding is an invaluable model for studying progression of cardiac hypertrophy and transition to heart failure. Traditional aortic banding has recently been superceded by minimally invasive transverse aortic banding (MTAB) which does not require ventilation so is less technically challenging. Although the MTAB procedure is superior, few laboratories have documented success and minimal information on the model is available. The aim of this study was to optimise conditions for MTAB and to characterise the development and progression of cardiac hypertrophy. Isofluorane proved the most suitable anaesthetic for MTAB surgery in mice and one week after surgery MTAB animals showed significant increases in systolic blood pressure (110±6 v's 78±3(mmHg), MTAB v's sham, n=7,p
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The aim of the present study was to compare the effect of lutein- and zeaxanthin-rich foods and supplements on macular pigment level (MPL) and serological markers of endothelial activation, inflammation and oxidation in healthy volunteers. We conducted two 8-week intervention studies. Study 1 (n 52) subjects were randomised to receive either carrot juice (a carotene-rich food) or spinach powder (a lutein- and zeaxanthin-rich food) for 8 weeks. Study 2 subjects (n 75) received supplements containing lutein and zeaxanthin, ß-carotene, or placebo for 8 weeks in a randomised, double-blind, placebo-controlled trial. MPL, serum concentrations of lipid-soluble antioxidants, inter-cellular adhesion molecule 1, vascular cell adhesion molecule 1, C-reactive protein and F2-isoprostane levels were assessed at baseline and post-intervention in both studies. In these intervention studies, no effects on MPL or markers of endothelial activation, inflammation or oxidation were observed. However, the change in serum lutein and zeaxanthin was associated or tended to be associated with the change in MPL in those receiving lutein- and zeaxanthin-rich foods (lutein r 0.40, P = 0.05; zeaxanthin r 0.30, P = 0.14) or the lutein and zeaxanthin supplement (lutein r 0.43, P = 0.03; zeaxanthin r 0.22, P = 0.28). In both studies, the change in MPL was associated with baseline MPL (food study r - 0.54, P <0.001; supplement study r - 0.40, P <0.001). We conclude that this 8-week supplementation with lutein and zeaxanthin, whether as foods or as supplements, had no significant effect on MPL or serological markers of endothelial activation, inflammation and oxidation in healthy volunteers, but may improve MPL in the highest serum responders and in those with initially low MPL.
Resumo:
Hypertension-induced left ventricular hypertrophy (LVH), along with ischemic heart disease, result in LV remodeling as part of a continuum that often leads to congestive heart failure. The neurohormonal model has been used to underpin many treatment strategies, but optimal outcomes have not been achieved. Neuropeptide Y (NPY) has emerged as an additional therapeutic target, ever since it was recognised as an important mediator released from sympathetic nerves in the heart, affecting coronary artery constriction and myocardial contraction. More recent interest has focused on the mitogenic and hypertrophic effects that are observed in endothelial and vascular smooth muscle cells, and cardiac myocytes. Of the six identified NPY receptor subtypes, Y-1, Y-2, and Y-5 appear to mediate the main functional responses in the heart. Plasma levels of NPY become elevated due to the increased sympathetic activation present in stress-related cardiac conditions. Also, NPY and Y receptor polymorphisms have been identified that may predispose individuals to increased risk of hypertension and cardiac complications. This review examines what understanding exists regarding the likely contribution of NPY to cardiac pathology. It appears that NPY may play a part in compensatory or detrimental remodeling of myocardial tissue subsequent to hemodynamic overload or myocardial infarction, and in angiogenic processes to regenerate myocardium after ischemic injury. However, greater mechanistic information is required in order to truly assess the potential for treatment of cardiac diseases using NPY-based drugs.
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Background Serum eosinophilic cationic protein (ECP) concentrations may be useful noninvasive markers of airways inflammation in atopic asthma. However, the usefulness of serum ECP measurement for the prediction of airways inflammation in children with a history of wheezing is unknown.
Resumo:
The management of overweight subjects by interventions aimed at reducing inflammation is highly desirable. To date, observational studies have identified a link between increased dietary antioxidant intake and reduced cardiovascular morbidity. However, direct trial evidence regarding the ability of antioxidants to influence inflammation is lacking. Therefore, this study examined lycopene's ability to lower systemic and high-density lipoprotein (HDL)-associated inflammation in moderately overweight middle-aged subjects. Serum was collected before and after a 12-week intervention from 54 moderately overweight, middle-aged individuals. Subjects were randomised to one of three groups: control diet (
Expression of suppressors of cytokine signalling (SOCS) in experimental cardiac transplant rejection
Resumo:
Cystic fibrosis (CF) is the most common inherited lethal disease in Caucasians which results in multiorgan dysfunction. However, 85% of the deaths are due to pulmonary infections. Infection by Burkholderia cenocepacia (B. cepacia) is a particularly lethal threat to CF patients because it causes severe and persistent lung inflammation and is resistant to nearly all available antibiotics. In CFTR Delta F508 (Delta F508) mouse macrophages, B. cepacia persists in vacuoles that do not fuse with the lysosomes and mediates increased production of IL-1 beta. It is believed that intracellular bacterial survival contributes to the persistence of the bacterium. Here we show for the first time that in wild-type but not in Delta F508 macrophages, many B. cepacia reside in autophagosomes that fuse with lysosomes at later stages of infection. Accordingly, association and intracellular survival of B. cepacia are higher in CFTR-Delta F508 macrophages than in WT macrophages. An autophagosome is a compartment that engulfs nonfunctional organelles and parts of the cytoplasm then delivers them to the lysosome for degradation to produce nutrients during periods of starvation or stress. Furthermore, we show that B. cepacia downregulates autophagy genes in WT and Delta F508 macrophages. However, autophagy dysfunction is more pronounced in Delta F508 macrophages since they already have compromised autophagy activity. We demonstrate that the autophagy-stimulating agent, rapamycin markedly decreases B. cepacia infection in vitro by enhancing the clearance of B. cepacia via induced autophagy. In vivo, rapamycin decreases bacterial burden in the lungs of CF mice and drastically reduces signs of lung inflammation. Together, our studies reveal that if efficiently activated, autophagy can control B. cepacia infection and ameliorate the associated inflammation. Therefore, autophagy is a novel target for new drug development for CF patients to control B. cepacia infection and accompanying inflammation.
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We hypothesised that primary bronchial epithelial cells (PBECs) from subjects with COPD respond differently to Pseudomonas aeruginosa lipopolysaccharide (PA LPS) after cigarette smoke extract (CSE) exposure than PBECs obtained from smokers without airflow obstruction (SWAO) and non-smokers (NS).PBECs from 16 COPD subjects, 10 SWAOand 9 NS were cultured at air-liquid interface. Cultures were incubated with CSE prior to stimulation with PA LPS. IL-6 and IL-8 were measured by ELISA and Toll-like receptor 4 expression by FACS. Activation of NF-?B was determined by western blotting and ELISA, and MAPK and caspase-3 activity by western blotting. Apoptosis was evaluated using Annexin-V staining and the terminal transferase-mediated dUTP nick end-labeling (TUNEL) methods.Constitutive release of IL-8 and IL-6 was greatest from the COPD cultures.However, CSE pre-treatment followed by PA LPS stimulation reduced IL-8 release from COPD PBECs, but increased it from cells of SWAOand NS. TLR-4 expression,MAPK and NF-?B activation in COPD cultures were reduced after CSE treatment, but not in the SWAOor NS groups, which was associated with increased apoptosis.CSE attenuates inflammatory responses to LPS in cells from people with COPD but not those from non-smoking individuals and those who smoke without airflow obstruction.