Search results for "polysaccharides"
showing 10 items of 413 documents
Responses of retinal arterioles and ciliary arteries in pigs with acute respiratory distress syndrome (ARDS)
2019
Abstract Acute respiratory distress syndrome (ARDS) is a clinical syndrome of acute lung failure in critically sick patients, which severely compromises the function of multiple organs, including the brain. Although, the optic nerve and the retina are a part of the central nervous system, the effects of ARDS on these ocular structures are completely unknown. Thus, the major goal of this study was to test the hypothesis that ARDS affects vascular function in the eye. ARDS was induced in anesthetized pigs by intratracheal injection of lipopolysaccharide (LPS). Sham-treated animals served as controls. Pigs were monitored for 8 h and then sacrificed. Subsequently, retinal arterioles and short p…
Highly efficient liposome-mediated gene transfer of inducible nitric oxide synthase in vivo and in vitro in vascular smooth muscle cells.
2000
Objective: The efficient introduction of regulatory genes into vascular smooth muscle cells (SMCs) is one of the most promising options for gene therapy of cardiovascular diseases. Cationic liposome-mediated gene transfer may become a favorable transfection technique with regard to patient’s safety for in vivo administration. However, this method until now has its limitation in a low transfection efficiency. Therefore, the present study was designed to improve cationic liposome-mediated transfection of rabbit vascular SMCs in vitro and in vivo, in order to enhance transfection efficiency and present an optimized system which may offer a potential therapeutic benefit for in vivo application.…
Cationic Proteins Inhibit l-Arginine Uptake in Rat Alveolar Macrophages and Tracheal Epithelial Cells
1999
Eosinophil-derived cationic proteins play an essential role in the pathogenesis of bronchial asthma. We tested whether cationic proteins interfere with the cationic amino-acid transport in alveolar macrophages (AMPhi) and tracheal epithelial cells, and whether L-arginine-dependent pathways were affected. The effect of cationic polypeptides on cellular uptake of [(3)H]-L-arginine, nitrite accumulation, and the turnover of [(3)H]-L-arginine by nitric oxide (NO) synthase and arginase (formation of [(3)H]-L-citrulline and [(3)H]-L-ornithine, respectively) were studied. Poly-L-arginine reduced [(3)H]-L-arginine uptake in rat AMPhi and tracheal epithelial cells in a concentration-dependent manner…
Serum antibodies to Vibrio vulnificus biotype 3 lipopolysaccharide and susceptibility to disease caused by the homologous V. vulnificus biotype
2011
SUMMARYIn 1996 an outbreak of severe soft tissue infections caused byVibrio vulnificusunexpectedly erupted in fish consumers in Israel with relatively little morbidity in fish farmers. To test the hypothesis that recurrent exposure of fishermen to the virulent strain may have provided protection against severe or symptomatic disease, we investigated the association between the immune response toV. vulnificusbiotype 3 lipopolysaccharide (BT3 LPS) and disease susceptibility in fish farmers and fish consumers. Serum samples were tested for IgA and IgG of anti-BT3 LPS in fishermen and fish consumers who suffered fromV. vulnificusBT3 infections and their matched controls. Pre-existing levels of …
Intravitreal injection of bevacizumab induces inflammatory alterations in a uveitis experimental model.
2010
PurposeBevacizumab is currently used as an intravitreal agent in the treatment of inflammatory-associated eye diseases. The aim of the current study is to explore the effects of the intravitreal injection of bevacizumab on aqueous humour cytokines and chemokines in an experimental uveitis model.MethodsEndotoxin-induced uveitis was induced in rats by footpad injections. Bevacizumab was administered by intravitreal injection (75 μg in 3–μL samples) and different chemokine and cytokine proteins were quantified in aqueous humor.ResultsIntravitreal administration of bevacizumab led to a several-fold increase of RANTES, MCP-1, and IFN-γ concentrations in aqueous humor of endotoxin-treated rats.Co…
Beta- and gamma-melanocortins inhibit lipopolysaccharide induced nitric oxide production in mice brain.
2003
The pro-opiomelanocortin-derived peptide alpha-melanocyte stimulating hormone (alpha-MSH) mediates many diverse physiological actions, including anti-inflammatory and immunomodulatory effects. However, little is known about the physiological roles of the other melanocortins, beta- and gamma-MSH. Here, we investigated the effects of melanocortin peptides in an in vivo neuroinflammation model. Six hours following intracisternal (i.c.) administration of 10 microg lipopolysaccharide (LPS) to mice a five-fold increase in the nitric oxide (NO) level was seen in the animals' brains, when detected by electron paramagnetic resonance (EPR). All tested melanocortins, alpha-, beta-, gamma1- and gamma2-…
Beta-MSH inhibits brain inflammation via MC(3)/(4) receptors and impaired NF-kappaB signaling.
2005
The anti-inflammatory effects of melanocortin peptides have been demonstrated in different inflammation models. This is the first report describing the molecular mechanisms for the beta-MSH-induced suppression of bacterial lipopolisaccharide (LPS)-caused brain inflammation. We found that beta-MSH suppresses LPS-induced nuclear translocation of the transcription factor NF-kappaB, and inhibits the expression of inducible nitric oxide synthase, and the following nitric oxide overproduction in the brain, in vivo. Moreover, administering the preferentially MC(4) receptor selective antagonist HS014 blocked completely these effects, suggesting a tentative MC(4) receptor mediated mechanism of actio…
Hepatic over-expression of TGF-beta1 promotes LPS-induced inflammatory cytokine secretion by liver cells and endotoxemic shock.
2005
Transforming growth factor-beta (TGF-beta) is an important suppressor of inflammation. However, TGF-beta has also been found to promote secretion of inflammatory cytokines, and transgenic mice, which constitutively express TGF-beta in liver, have been found to be more susceptible to endotoxemia. To approach this apparent paradox, we investigated the role of hepatic TGF-beta1 in endotoxemia by utilising inducible TGF-beta1-transgenic mice that express TGF-beta1 under control of the C-reactive protein promoter. In contrast to non-transgenic littermates, administration of lipopolysaccharide (LPS) induced strongly increased expression of TGF-beta and acute phase proteins in the TGF-beta1-transg…
Whole blood endotoxin responsiveness in patients with chronic heart failure: the importance of serum lipoproteins.
2005
Background Endotoxin [lipopolysaccharide (LPS)] may be an important stimulus for cytokine release in patients with chronic heart failure (CHF). We sought to investigate the relationship between whole blood endotoxin responsiveness and serum lipoprotein concentrations. It is not known if low-dose LPS is sufficient to stimulate immune activation. Methods and results Whole blood from 32 CHF patients (mean age 66±2 years, NYHA class 2.7±0.2, five female) and 11 healthy control subjects (mean age 47±4 years, six female) was stimulated with LPS at nine different concentrations (0.001 to 10 ng/mL), and tumor necrosis factor (TNF-α) release was quantified. Reference standard endotoxin at concentrat…
Transcriptional up-regulation of nNOS in the dorsal vagal complex during low endotoxemia
2005
The present study analyses the expression and distribution of neuronal nitric oxide synthase (nNOS) in the brainstem of animals pre-treated with Escherichia coli or Helicobacter pylori LPS, at doses that modulate gastric motor function. Systemic administration of H. pylori LPS prevented in a dose-dependent manner (5, 40 and 100 microg kg(-1), i.v.) the increase in intragastric pressure induced by 2-deoxy-D-glucose (200 mg kg(-1), i.v.) in urethane-anaesthetized rats. Quantitative analysis showed a significant increase in the amount of nNOS mRNA induced by E. coli or H. pylori LPS (2 h later), in a segment of the brainstem containing the dorsal vagal complex (DVC). Immunohistochemical studie…