Kinetics of activation of the NADPH oxidase in a fully soluble cell-free system from phorbol myristate acetate (PMA)-stimulated human neutrophils were investigated. In a cell-free system in which Mg{sup 2+} and sodium dodecyl sulfate, an anionic detergent required for the activation of NADPH oxidase are contained, cytosol prepared from ...
Energy Citations Database
The respiratory burst of stimulated neutrophils can cause oxidative modifications of endogenous neutrophil proteins as measured by increased carbonyl formation. Ceruloplasmin is an acute phase protein and may act as an antioxidant during inflammation. Therefore, the role of ceruloplasmin in preventing oxidative damage of endogenous ...
Using swine neutrophils as target cells, two MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium) colorimetric assay systems, one with and one without phorbol 12-myristate 13-acetate (PMA) stimulation were established for the quantitation of Actinobacillus pleuropneumoniae cytotoxin. The MTT assays were ...
PubMed Central
Diabetic patients are prone to severe bacterial infections. The functional alterations of neutrophils by hyperglycemia are thought to be partially responsible for such infections. In this study, we investigated the functional changes of neutrophil-like differentiated cell lines (dHL-60, dTHP-1, and dNB-4) by treatment with 5.5 mM, 11 mM, or 35 mM of ...
PubMed
Many previous reports using experimental animal models of pancreatitis have suggested that oxygen free radicals play an important part in initiation and development of pancreatitis. Infiltration of inflammatory cells--that is, neutrophils, lymphocytes, and monocytes--has been seen in damaged pancreatic glands of animal models and patients with pancreatitis. As ...
The phorbol myristate acetate (PMA) stimulated nutrophil respiratory burst has been considered to simply involve the activation of protein kinase C (PKC). However, the PLD activity was also increased by 10-fold in human neutrophils stimulated with 100 nM PMA. Unexpectedly, U73122, an inhibitor of phospholipase C, ...
The authors have shown that pretreatment with ibuprofen inhibits free radical release from complement stimulated neutrophils. To further examine the effect of ibuprofen on neutrophil free radical release, they stimulated neutrophils with the synthetic peptide, FMLP, phorbol myristate acetate (PMA), or ...
Stimulated neutrophils produce oxygen radicals which may cause injury to endothelial cells during inflammatory diseases. Ceruloplasmin is an acute phase protein in which serum levels can increase 2-3 fold during inflammation. Ceruloplasmin may act as an extracellular antioxidant by oxidizing iron and mediating iron-dependent oxygen radical production. The role of ceruloplasmin ...
Antimicrobial proteins in neutrophil granules exert their bactericidal activity both within the neutrophil phagolysosome and as components of neutrophil extracellular traps. This study evaluated the bactericidal activity of porcine neutrophil secretions against four bacterial pathogens of swine. Porcine ...
In this study the anti-inflammatory potential of potassium humate, derived from bituminous coal, has been investigated in vitro. Exposure of resting and phorbol-12-myristate-13-acetate (PMA) stimulated human neutrophils to potassium humate resulted in a decreased expression of CR3 by activated, but not resting ...
Generation of reactive oxygen species by the NADPH oxidase complex is an important bactericidal weapon of phagocytes. Phorbol myristate acetate (PMA) is a potent agonist for this "respiratory burst" in human neutrophils. Although stoichiometric H(+) efflux occurs during the respiratory burst, efforts to stimulate voltage-gated H(+) channels by PMA in ...
Systemic activation of complement following intravenous injection of CVF causes acute pulmonary microvascular injury. This injury is caused by release of neutrophil-derived oxygen radicals in the pulmonary microvasculature after complement activation. Phorbol myristate acetate (PMA)-stimulated neutrophils exposed ...
1. Proton and electron currents in human eosinophils were studied using the permeabilized-patch voltage-clamp technique, with an applied NH4+ gradient to control pH(i). 2. Voltage-gated proton channels in unstimulated human eosinophils studied with the permeabilized-patch approach had properties similar to those reported in whole-cell studies. 3. Superoxide anion (O2-) release assessed by ...
A neutral serine proteinase, purified 250-fold from the plasma membrane fraction of human neutrophils, differs in its catalytic and molecular properties from the well-known neutral proteinases present in azurophil (primary) granules. Stimulation of neutrophils with low concentrations of phorbol 12-myristate 13-acetate (PMA) results in ...
Menadione, a derivative of the natural vitamins K, has antineoplastic and antiinflammatory properties. Its profound biochemical effects upon resting and stimulated neutrophils make these cells a likely target of its purported therapeutic actions. They found superoxide dismutase-inhibitable O/sub 2/ production, a major mechanism of leukocyte-mediated cell damage, to be enhanced ...
Agelanthus dodoneifolius DC Danser (Loranthaceae) is used for the treatment of various diseases including asthma. The aqueous and hydroalcoholic extracts have been reported to have anti-inflammatory, spasmolytic and bronchorelaxant activities. The present study investigates the effects of the aqueous decoction and the diethyl ether, ethyl acetate and butanolic fractions of ...
The biochemistry and subcellular source of new formyl peptide chemotactic receptor appearing at the human neutrophil and differentiated HL-60 (d-HL-60) cell surface after stimulation with phorbol myristate acetate (PMA) were examined. Formyl peptide receptor was analyzed by affinity labeling with formyl-norleu-leu-phe-norleu- (/sup 125/I)iodotyr-lys and ...
Punica granatum peel aqueous extract (PGE) is widely used to treat disorders such as inflammation, ulcers and infections, but its pharmacological target is not known. In this study we investigated the effect of PGE on human neutrophil reactive oxygen species (ROS) production in vitro and on LPS-induced lung inflammation in vivo in mice. Neutrophils were ...
Generation of reactive oxygen species by the NADPH oxidase complex is an important bactericidal weapon of phagocytes. Phorbol myristate acetate (PMA) is a potent agonist for this �respiratory burst� in human neutrophils. Although stoichiometric H+ efflux occurs during the respiratory burst, efforts to stimulate voltage-gated ...
The effect of electron-beam intraoperative radiotherapy (IORT) with radiosensitizer sanazole (drug AK-2123) on the functional activity of neutrophils and monocytes in patients with gastric cancer was studied with the use of luminol-amplified chemiluminescence. Sanazole was administered intravenously in a dose of 1.2 g/m2, 30 min before IORT. After resection of the tumor a ...
PMA produced injury to isolated, perfused rat lungs when eutrophils were added to or omitted from the buffer/albumin perfusion medium. When a high dose of PMA (57 ng/ml) was added to medium devoid of added neutrophils, perfusion pressure and lung weight increased. Together, superoxide dismutase (500 U/ml) and catalase (400 U/ml) had no effect on the increases in lung weight or ...
Leukocyte-induced DNA damage may partially account for the known association between chronic inflammation and malignancy. Since elucidation of the chemical nature of leukocyte-induced DNA damage may enhance our understanding of the mechanisms underlying leukocyte-induced DNA damage and the carcinogenesis associated with inflammation, the present study was undertaken to characterize the chemical ...
Proton and electron currents in human eosinophils were studied using the permeabilized-patch voltage-clamp technique, with an applied NH4+ gradient to control pHi.Voltage-gated proton channels in unstimulated human eosinophils studied with the permeabilized-patch approach had properties similar to those reported in whole-cell ...
The present study aims at investigating the effect of bovine serum albumin (BSA) on the trial of oxidative-stress. The antioxidant effects of BSA were determined by human neutrophil granulocytes oxygen free radicals and their by-products (O2-, H2O2, HOCl) productions. BSA interacts with those reactive oxygen species (ROS) in a dose-dependent manner. The 50% inhibitory ...
Neutrophil (PMN) contribution to the acute inflammatory processes may lead to an excessive generation of reactive oxygen metabolites species (ROS) and secretion of granule enzymes. We compared the effects of either phorbol myristate acetate (PMA) or N-formyl-methionyl-leucyl-phenylalanine (fMLP) in combination with a pre-treatment by cytochalasin B (CB) on ...
Phorbol12-myristate 13-acetate (PMA) stimulated radiolabelled choline uptake and incorporation. The accumulation of labelled choline induced by PMA was paralled by an increase in choline mass. The results implicate protein kinase C (PKC) in the regulation of choline uptake. In order to address the PKC- subtype
E-print Network
Haemolytic uraemic syndrome (HUS) is caused by Shiga-toxin-producing Escherichia coli (STEC). Although, Shiga toxin type 2 (Stx2) is responsible for the renal pathogenesis observed in patients, the inflammatory response, including cytokines and polymorphonuclear neutrophils (PMN), plays a key role in the development of HUS. Previously, we demonstrated that Stx2 injection ...
Body temperature can modulate the pathogenesis of infectious, metabolic and autoimmune diseases. This effect has been attributed to several hypothesized mechanisms. Body temperature could play an important role in influencing some cellular functions of human white blood cells. In this work we examined the temperature effect on the respiratory burst in human neutrophils. Human ...
The combined presence of platelets (PLTS) and neutrophils (PMN) at inflammatory sites has led to examination of the hypothesis that interaction of these cells modulates their responses to stimuli. Gel-filtered human PLTS (GFP) were found to inhibit N-formyl-met-leu-phe (FMLP) and phorbol myristate acetate (PMA) ...
We have studied whether curcumin prevents amiodarone-induced lung fibrosis in rats. Intratracheal instillation of amiodarone (6.25 mg kg?1 on days 0 and 2, and then killed on day 3, day 5, week 1, week 3 and week 5 after amiodarone administration) induced increases in total protein and lactate dehydrogenase (LDH) activity on days 3 and 5 in bronchoalveolar lavage fluid ...
Calprotectin, a heterodimer of MRP8 and MRP14 with antimicrobial properties, is found in the cytosol of neutrophils, monocytes, and human gingival keratinocytes. During inflammation of the oral mucosa, the expression of immunoreactive calprotectin appears upregulated. Given the possible cell sources, we sought to learn if epithelial cells upregulate calprotectin in response to ...
1. The effect of NPC 15669, N-carboxy-L-leucine, N-[(2,7-dimethylfluoren-9-yl)methyl]ester), an inhibitor of human polymorphonuclear neutrophil (PMN) adhesion, on granule exocytosis and the oxidative burst was investigated in PMN activated with receptor-specific pathophysiological stimuli. 2. NPC 15669 caused a concentration-dependent (1-30 microM) inhibition of the ...
Altered antioxidant status has been implicated in schizophrenia. Microglia, major sources of free radicals such as superoxide (�O(2)(-)), play crucial roles in various brain pathologies. Recent postmortem and imaging studies have indicated microglial activation in the brain of schizophrenic patients. We previously demonstrated that atypical antipsychotics including aripiprazole significantly ...
The antagonization of phorbol 12-myristate 13-acetate (PMA)-stimulated phosphatidylcholine (PtdCho) biosynthesis by the phospholipid analogue hexadecylphosphocholine (HePC) in MDCK cells was investigated and compared with the corresponding influence in HeLa cells. In both cell lines, PMA-stimulated PtdCho biosynthesis was antagonized ...
Neutrophils are the first barrier against infections. Aged neutrophils display impaired oxidative burst and phagocytosis with subsequent less capability to destroy bacteria. In successful ageing (nonagenarians), neutrophil efficiency (phagocytosis) increases. After ingested microbes, aged neutrophils are less prone ...
Impaired neutrophil function has been associated with increased infectious diseases in ruminants. Attachment of neutrophils to endothelium and superoxide production is critical features of their immune activity. Once the infection is cleared, programmed cell death ensures the rapid resolution of inflammation. To develop new natural therapeutics for ...
Administration of non-toxic concentrations (10�?M) of cytochalasin b and nocodazole to larvae of Galleria mellonella increased their susceptibility to infection by the yeast Candida albicans. These agents were found to inhibit the process of phagocytosis and to reduce the killing ability of haemocytes. In addition, both cytochalasin b and nocodazole reduced the release of antimicrobial peptides ...
Neutrophils are of prime importance in the host innate defense against invading microorganisms by using two primary mechanisms-locomotion toward and phagocytosis of the prey. Recent research points to pivotal roles for water channels known as AQPs in cell motility. Here, we focused on the role of AQP9 in chemoattractant-induced polarization and migration of primary mouse ...
In the present study, the immunomodulatory effect of {beta}-endorphin ({beta}-E) and shorter pro-opiomelancortin (POMC) fragments was evaluated by assessing their influence on respiratory burst in human polymorphonuclear leukocytes (PMN). The effect of the peptides on phorbol myristate acetate (PMA)-stimulated production of reactive oxygen metabolites was ...
ABSTRACT: INTRODUCTION: Levosimendan is an extensively investigated inodilator showing also cardioprotective and antiinflammatory effects. The aim of our study was to explore the influence of levosimendan on polymorphonuclear leucocytes (PMN), a main source of reactive oxygen species, in vitro and in patients with acute heart failure or septic myocardial depression. METHODS: PMN isolated from ...
Phorbol 12-myristate 13-acetate (PMA) stimulated radiolabelled choline uptake and incorporation into phosphatidylcholine (PtdCho) in a time- and concentration-dependent manner in wild-type NIH 3T3 fibroblasts. The accumulation of labelled choline induced by PMA was paralled by an increase in choline mass. The results implicate protein ...
Interferon-gamma (IFN-gamma) enhanced the cytotoxic capability of freshly isolated human blood monocytes but failed to enhance the tumoricidal competence of monocyte-derived macrophages. Treatment of monocytes with IFN-gamma (100 U/ml) caused a significant increase (P < 0.001) in lucigenin-dependent chemiluminescence and O2- production stimulated by N-formyl-L-methionyl-L-leucyl-L-phenylalanine ...
Leukocyte adhesion deficiency type III is a recently described condition involving a Glanzmann-type bleeding syndrome and leukocyte adhesion deficiency. This was ascribed to a defect of the FERMT3 gene resulting in abnormal expression of kindlin-3, a protein expressed in hematopoietic cells with a major role in the regulation of integrin activation. In this article, we describe a patient with a ...
Fresh semen was collected from adult male giant pandas and the role of Ca2+, Ca2+ ionophore A23187 and protein kinase C (PKC) in sperm motility and acrosome reaction (AR) was assessed by lens culinaris agglutinin conjugated with fluorescein isothiocyanate (FITC-LCA) labeling and transmission electron microscopy. The AR in giant panda spermatozoa was characterized by vesiculation of the outer ...
Pulmonary alveolar macrophages (PAM) and peripheral blood monocytes (PBMo) of the miniature swine can be converted to cytolytically active cells by treating with phorbol myristic acetate (PMA) or combined stimulation with recombinant human interferon - ..gamma.. (rHuIFN-..gamma..) and lipopolysaccharide (LPS). These activated PAM and PBMo become cytolytic to various targets by ...
Matrix metalloproteinases are implicated in a wide range of pathophysiological processes and potent selective inhibitors for these enzymes continue to be eagerly sought. 5,5-Disubstituted barbiturates hold promise as inhibitor types being stable in vivo and relatively selective for the gelatinases (MMP-2 and MMP-9). In this paper we describe the synthesis of 5-piperazine and -homopiperazine ...
Rapid endosomal escape of drug carriers is crucial to enhancing the efficacy of their macromolecular payload, especially proteins that are susceptible to lysosomal degradation. In this paper, we report poly(amino oxalate) (PAOX) as a new protein delivery system that is capable of disrupting endosomes and mediating cytosolic drug delivery. A cationic fully-biodegradable PAOX was synthesized from a ...
Members of the family of transmembrane integral membrane proteins called integrins have been implicated in forming attachments to actin microfilaments of the cytoskeleton. These attachments are though to involve one or more intervening peripheral membrane proteins linked to integrin. To detect such possible linkages in vivo, the integrin molecules on the surfaces of intact chicken peripheral blood ...
To study the role of high-affinity receptors in thrombin mitogenesis, experiments have been carried out in three main areas: (1) development and selection of a monoclonal antibody to the thrombin receptor; (2) use of synthetic peptides as receptor probes; and (3) purification and characterization of the thrombin receptor. The monoclonal antibody that was developed and selected, TR-9 inhibits from ...
Neurotransmitters have been demonstrated to be important modulators of immune regulation. The authors have previously demonstrated that the catecholamine agonists isoproterenol (Iso), epinephrine (Epi), and norepinephrine (Nor) are potent inhibitors of IFN{gamma} production by phorbol myristate acetate (PMA) stimulated T-cell lymphoma ...
Macrophages play an important role in immune and inflammatory responses, largely through secretion of bioactive molecule such as cytokines. While calcium is known to be an important regulator of this process, less is known about the role of other ions and the ion channels that regulate them. We have previously implicated an outwardly rectifying potassium channel (Kor) in this process and for this ...
Sprint interval training (SIT) is a potent stimulus for physiological and metabolic adaptations comparable with those induced by traditional "aerobic" endurance training. There has been a great deal of recent research on SIT, which may lead to increased use of this type of training. The purpose of the present study was to determine the acute effects of SIT on aspects of innate immunity not ...
Mechanisms of leukocyte NADPH oxidase regulation remain actively investigated. We showed previously that vascular and macrophage oxidase complexes are regulated by the associated redox chaperone PDI. Here, we investigated the occurrence and possible underlying mechanisms of PDI-mediated regulation of neutrophil NADPH oxidase. In a semirecombinant cell-free system, PDI ...
A monoclonal antibody against rat neutrophils, RP-1, was produced by hybridizing a mouse myeloma (P3-X63-Ag8.653) with BALB/c mouse spleen cells sensitized with peritoneal neutrophils from Wistar-King-Aptakeman/Hok rats. RP-1 specifically reacted to neutrophils and bone marrow cells from rats of various strains. The expression of an ...
The anti-inflammatory effect of the medicinal plant, Commiphora mukul gum was studied in peripheral blood mononuclear cells (PBMC). Bioassay-guided fractionation using conventional solvent extraction procedures, subsequent column fractionation, followed by monitoring specific activity in PBMC led to the isolation of a lead compound. Both crude ethyl acetate extract and the ...
In rat striatal synaptosomes, 4..beta..-phorbol 12-myristate 13-acetate (PMA) and 4 ..beta..-phorbol 12,13-dibutyrate (PDBu), two activators of Ca/sup 2 +/-phospholipid-dependent protein kinase (protein kinase C) increased dopamine (DA) synthesis measured by following the release of /sup 14/CO/sub 2/ from L-(1-/sup 14/C) tyrosine. Maximal stimulation (21-28% increase of basal ...
Phorbol 12-myristate 13-acetate (PMA) is known to affect a variety of cellular processes, including cell proliferation, differentiation, and migration. PMA has been shown to promote antiproliferative and antimigratory effects in many types of cancer cells. Our findings show that PMA induced a strong antiproliferative effect in two anaplastic (FRO and ARO) and one follicular ...
Calcium concentration influences keratinocyte differentiation, and, following injury, keratinocytes move through an environment of changing calcium levels. Because these migrating cells in wounds invariably express collagenase 1, we assessed if modulation of calcium levels regulates collagenase 1 production by primary human keratinocytes. Accurately reflecting the confined spatial pattern of ...
Ethanol inhibits the respiratory burst of neutrophils. Therefore, the effects of alcohol-based skin disinfection on oxygen metabolism in neutrophils were tested using 70% ethanol or an ethanol�isopropanol�n-propanol mixture. Neutrophil respiratory burst activity as assessed fluorometrically by oxidation of 2?,7?-dichlorofluorescein ...
The population dynamics of single-cell stimulation was analyzed by monitoring autofluorescence by flow cytometry. Stimulatin of the respiratory burst in human neutrophils by 12-O-tetradecanoyl phorbol-13-acetate (TPA) caused a decline in highly fluorescent cells (characteristic of resting neutrophils) and a correspondng increase in the ...
Monocyte chemoattractant protein?3 (MCP?3) is one of the most broadly active chemokines, potentially inducing chemotaxis of all leucocytic cells. In the present study, we examined the regulation of MCP?3 mRNA and protein production in endothelial cells by protein kinase C (PKC) activator, phorbol 12?myristate 13?acetate (PMA) and cAMP signalling. On stimulation of endothelial ...
BackgroundResistin is a cysteine rich protein, mainly expressed and secreted by circulating human mononuclear cells. While several factors responsible for transcription of mouse resistin gene have been identified, not much is known about the factors responsible for the differential expression of human resistin.Methodology/Principal FindingWe show that the minimal promoter of human resistin lies ...
The prevailing hypothesis that a signalling pathway involving cPLA2? is required to enhance the gating of the voltage-gated proton channel associated with NADPH oxidase was tested in human eosinophils and murine granulocytes. This hypothesis invokes arachidonic acid (AA) liberated by cPLA2? as a final activator of proton channels. In human eosinophils ...
Reactive free radicals contained in cigarette smoke (CS) and compromised phagocytic antimicrobial activities including those of polymorphonuclear leukocytes (PMNs) have been implicated in the pathogenesis of severe CS-related pulmonary disorders. In CS-exposed buffer solutions, O2-. was the predominant generated reactive oxygen species, as demonstrated by lucigenin-amplified chemiluminescence and ...
Ribosomal protein S6 kinase activity was measured in lysates prepared from serum-deprived chicken embryo fibroblasts (CEF) treated for various times with phorbol 12-myristate 13-acetate (PMA). Maximal activity was observed within 15 min, and it declined to the initial level by 4 hr. Incubation of these cells with PMA 4-60 hr after the initial treatment did not result in an ...
Effects of phorbol esters and epidermal growth factor (EGF) on prostaglandin E/sub 2/ production by cultured porcine thyroid cells were examined. Both phorbol 12-myristate 13-acetate (PMA) and EGF stimulated prostaglandin E/sub 2/ production by the cells in dose related fashion. PMA stimulated prostaglandin E/sub 2/ production over ...
It has been shown that addition of hCG or c-AMP to cultured Leydig tumor cells (MA-10) increases synthesis of progesterone as the major steroid. To investigate the possible involvement of protein kinase C (PK-C) in the regulation of steroid synthesis, the authors have studied the effect of PMA, an activator of PK-C, on progesterone production in MA-10 cells. The addition of PMA (100 ng/ml) ...
The purpose of this study was to prepare and characterize nanocarrier systems, which allow the application of pDNA vaccines and adjuvants to mucosal vaccination. Chitosan from a vegetal source (Agaricus bisporus) and of GMP quality was used to synthesize the derivative 6-O-carboxymethyl-N,N,N-trimethylchitosan (CM-TMC). Toll-like receptor-2 (TLR-2) agonist, Pam(3)Cys, was synthesized and coupled ...
A novel series of perfluorocarbon (PFC) emulsions, based on perfluorodecalin (C10F18) and stabilised with up to 2.5% (w/v) of lecithin have been produced for evaluation as injectable, temporary respiratory gas-carrying blood substitutes. Some formulations contained 1.0% (w/v) of perfluorodimorpholinopropane (C11F22N2O2) to retard droplet growth through molecular diffusion (Ostwald Ripening). Other ...
The genetically selected high antibody responder line of mice (HIII) for a natural immunogen were fully susceptible to mouse hepatitis virus 3 (MHV3) and the corresponding low antibody responder mice (LIII) were fully resistant, regardless of whether they were previously treated or not with the bacillus Calmette-Gu�rin (BCG). The resistance or susceptibility correlated with the virus growth in ...
The solute carrier family 11 member 1 (SLC11A1) gene is strictly regulated and exclusively expressed in myeloid lineage cells. However, little is known about the transcriptional regulation of the SLC11A1 gene during myeloid development. In this study, we used HL-60 cells as a model to investigate the regulatory elements/factors involved in the transactivation of the SLC11A1 gene during phorbol ...
The aims of the present study were to determine the role of protein kinase C (PKC) on meiotic resumption and its effects on pronuclear formation and cleavage in the bovine. Oocytes were matured in the presence of 0, 1, 10 and 100 nM of phorbol 12-myristate 13-acetate (PMA), to evaluate the percentage of germinal vesicle breakdown. To study pronuclear formation and cleavage, ...
When platelets are activated by agonists, calcium (Ca2+) is released from an intracellular storage site. Recent studies using fura-2 show that, after thrombin stimulation, the rise in free calcium is transient and returns to base-line levels in 2-3 min, while the transient following ADP stimulation lasts only 15-20 s. We reported previously that the phorbol ester 12,13-phorbol myristate ...
Here we show that stimulation of protein kinase C (PKC) by phorbol 12-myristate 13-acetate (PMA) treatment induces a time-dependent decrease in glutamate transport activity due to relocalization of the excitatory amino acid carrier 1 (EAAC1) glutamate transporter from the apical surface of polarized epithelial Madin-Darby canine kidney (MDCK) cells to intracellular ...
Little is known regarding the mechanism(s) by which glycine receptors are endocytosed. Here we examined the endocytosis of homomeric ?1 glycine receptors expressed in HEK 293 cells using immunofluorescence/confocal microscopy and whole-cell patch-clamp recordings. Our studies demonstrate that constitutive endocytosis of glycine receptors is blocked by the dominant negative dynamin construct K44A ...
The goal of this study was to evaluate the anticancer effect of Prunus salicina Lindl. cv. Soldam at three maturity stages (immature, midmature and mature). In search for anticancer effects of immature plum extract (IPE), we have found its antimigrative property in (phorbol 12-myristate 13-acetate) PMA-induced HepG2 cells, and this effect is associated with inhibition of MMP-9 ...
Rac2 is a Rho family GTPase that is widely expressed in hematopoietic cells and plays a critical role in host defense. This study investigates the mechanisms responsible for increased Rac2 gene expression during myeloid cell differentiation. Treatment of K562 chronic myelogenous leukemia cells with phorbol-12-myristate-13-acetate (PMA) induces megakaryocytic differentiation ...
Aromatase cytochrome P450 mRNA and activity was strongly expressed in THP 1 myeloid leukaemia cells after treatment with phorbol-myristate-acetate (PMA) and dexamethasone, low level expression was caused by calcitriol. mRNA species of 4.0, 3.0, 2.4 and 1.1 kb size were differentially stimulated. After calcitriol-mediated differentiation (72 h, measured by CD 14 expression) ...
We developed an electrochemical-sensing device for continuous monitoring extracellular hydrogen peroxide (H(2)O(2)). The device consists of an indium-tin-oxide electrode coated with osmium-polyvinylpyridine gel polymer containing horseradish peroxidase (Os-HRP) and a poly-dimethyl siloxane well to house the cells on the chip. Granulocyte-like differentiated HL-60 cells were accommodated in the ...
This study was performed to examine the effect of different fat sources, lard, sunflower oil (SO), and fish oil (FO) in high-fat and low-fat diet on reactive oxygen species generation by blood phagocytes, glutathione redox status in erythrocytes, and total plasma antioxidant ability in rats. Whole blood chemiluminescence (CL) did not differ between three low-fat fed groups. However, baseline and ...
Phorbol 12-myristate 13-acetate (PMA), norepinephrine (NE), angiotensin II (AII) and contraction stimulate cardiomyocyte growth. Differences exist in the time course and extent of protein and RNA accumulation. Cells plated at 4 {times} 10{sup 6} cells/60mm dish and arrested with 50 mM KCl demonstrated no significant growth. Treatment with PMA ...
A novel strategy has been suggested to enhance rapamycin-based cancer therapy through combining mammalian target of rapamycin (mTOR)-inhibitors with an inhibitor of the phosphatydilinositol 3-kinase PI3K/Akt or mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway. However, recent study demonstrated the potentiating effect of rapamycin on all-trans-retinoic acid ...
T-cell activation and induction of interleukin-2 (IL-2) expression in human T lymphocytes require both interaction of foreign antigen with the T-cell antigen receptor and protein kinase C (PKC) stimulation. Agents such as phorbol 12-myristate 13-acetate (PMA) that stimulate PKC augment the effects of antigen but are not sufficient for IL-2 activation. By analysis of deletion ...
BackgroundCongaplex� and Immuplex� are dietary supplements that have been traditionally used to support immune system function. The purpose of these experiments was to determine whether Congaplex� and Immuplex� affect immune function using primary and immortalized T lymphocytes.MethodsImmortalized ...
In this report we introduce a simple, fast, and reliable method to prepare whole cell or nuclear extracts from small numbers of cells. These extracts were used to study transcriptional activation of the human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR) in vitro. Our results revealed that the time courses of activation of extracts derived from cells stimulated with the ...
Activation of calcium-activated, phospholipid-dependent protein kinase C by diacylglycerol and phorbol esters has been shown to mediate release of hormones in many systems. To determine whether protein kinase C activation is also involved in the regulation of prolactin release from human decidual, the authors have examined the effects of various acylglycerols and phorbol esters on the synthesis ...
Selected host defense functions of neutrophils isolated from American bison (Bison bison) were characterized and compared with those of cattle (Bos taurus). Bison neutrophils had a robust chemotactic response to both IL-8 and LTB(4), with maximal responses occurring at 10(-7) M (IL-8) and 10(-8) M (LTB(4)). The magnitude of the chemotactic response to IL-8 ...
Complement alternative pathway plays an important, but not clearly understood, role in neutrophil-mediated diseases. We here show that neutrophils themselves activate complement when stimulated by cytokines or coagulation-derived factors. In whole blood, tumor necrosis factor/formyl-methionyl-leucyl-phenylalanine or phorbol myristate ...
Naegleria fowleri is the cause of primary amoebic meningoencephalitis in man. The mouse is considered to be a suitable experimental model for this disease. The data presented shows that blood neutrophils from N. fowleri immune mice (immunised) that had received a 'recall' amoeba antigen had altered responses compared with those from similarly treated normal mice. The ...
Angiotensin-converting enzyme (ACE) is an enzyme that plays a major role in vasoactive peptide metabolism, and it has been implicated in various cardiovascular diseases. Phorbol 12-myristate 13-acetate (PMA), a protein kinase C activator, has been shown to increase ACE mRNA at the transcriptional level in human umbilical vein endothelial cells. We have investigated the ...
The neutrophil oxidative burst plays an important role in killing intracellular microorganisms. We studied the effects of topical antimicrobial agents on the N-formyl-L-methionyl-L-leucyl-L-phenylalanine-stimulated oxidative burst of human peripheral blood neutrophils, using a flow cytometric assay. Mafenide acetate, sulfadiazine ...
The effect of biomaterials on the superoxide-producing ability of neutrophils was studied. Human peripheral blood neutrophils were incubated with cobalt-base alloy (F-75) or polystyrene beads of a nonphagocytosable size. Respiratory burst activity was studied by measuring superoxide dismutase inhibitable reduction of cytochrome C. ...
Expression of CD18 on bovine neutrophils in response to stimulation by zymosan activated serum (ZAS) and phorbol myristate acetate (PMA) and the effects of monoclonal antibodies (MAB) recognizing CD18 or bovine neutrophil surface antigens (S2G8 and S5F8G10) on adherence, chemotactic responses and phagocytosis of bovine ...
Nuclei from mature neutrophil granulocytes were prepared from peritonal exudates of goats. Fluorescein mercuric acetate was required to stabilize the nuclei and fix nucleoproteins. Following differential centrifugation and detergent treatment, electron mi...
National Technical Information Service (NTIS)
Exposure to combined suboptimal concentrations of 4..beta..-phorbol 12-myristate 13-acetate and the calcium ionophore A23187 stimulates superoxide release from guinea pig neutrophils to rates ca. 3.5-fold greater than the sum of the rates elicited by each of the agents added separately. This effect was largely dependent upon the presence of calcium in the ...
Exogenous long-chain (sphingoid) bases are potent inhibitors of protein kinase C in vitro and the oxidative burst of human neutrophils. To assess their involvement in neutrophil function, high-performance liquid chromatography was used to quantitate free long-chain bases in neutrophils incubated with and without ...
Two Holstein heifers with persistent and recurrent infections including ulcerative gingivitis, periodontitis, pneumonia, loss of teeth and stunted growth associated with marked neutrophilia were evaluated clinically and for neutrophil function, CD18 expression on neutrophils and CD18 genotype analysis by DNA-polymerase chain reaction (PCR) test. Adherence ...
Leucocyte transendothelial migration is strictly regulated to prevent undesired inflammation and collateral damage of endothelial cells by activated neutrophils/monocytes. We hypothesized that in anti-neutrophil cytoplasmic autoantibodies (ANCA)-associated vasculitis (AAV) patients' dysregulation of this process might underlie vascular inflammation. ...
Human neutrophils stimulated with phorbol myristate acetate were able to destroy suspensions or monolayers of cultured human endothelial cells. Neutrophil-mediated cytotoxicity was related to phorbol myristate acetate concentration, time of incubation and neutrophil number. Cytolysis was ...
NADPH-dependent superoxide production by intact human neutrophils is inhibited by DPI (diphenyleneiodonium), when stimulated by either FMLP (N-formylmethionyl-leucyl-phenylalanine) or PMA (phorbol 12-myristate 13-acetate). Addition of 10 microM-DPI abolished the reduction of both the FAD and the cytochrome b components of the NADPH oxidase. DPI inhibition ...
Human neutrophils contain receptors for phorbol myristate acetate (PMA), a complex lipid that induces them to generate superoxide (O (2)). Binding of PMA to these receptors displays specificity, reversibility, and high affinity. The receptor's apparent KD was approximately 0.29 nM and multiple copies (approximately 2.1 +/- 0.6 x 10(5)) were present per ...
Oxidant gas exposure leads to lung injury characterized by acute inflammation, connective tissue breakdown and alveolar damage. In an effort to better understand the mechanism for oxidant gas injury human peripheral neutrophils were isolated and incubated with /sup 14/C-proline labelled extracellular matrix. Neutrophils in the presence of phorbol myristate ...
Human neutrophils stimulated with a phorbol ester (phorbol 12-myristate 13-acetate or phorbol 12,13-dibutyrate) responded with an increase in diacylglycerol, considered the natural activator of protein kinase C. The amounts of diacylglycerol formed were considerable, reaching 700-900% of basal after 20 minutes. In contrast, 4-{alpha}-phorbol 12-myristate ...
Spleen cells from male (CBA/N x DBA/2) F1 hybrid mice do not significantly respond to in vitro stimulation by trinitrophenyl-conjugated polyacrylamide beads (TNP-PAA), whereas the same antigen elicits high PFC responses in female F1 hybrid cells. Therefore, this antigen could be classified as a T-independent type 2 (TI-2) antigen. When male spleen cells were co-stimulated by TNP-PAA and TI type 1 ...
The ways in which human cytomegalovirus (HCMV) major immediate-early (MIE) gene expression breaks silence from latency to initiate the viral replicative cycle are poorly understood. A delineation of the signaling cascades that desilence the HCMV MIE genes during viral quiescence in the human pluripotent N-Tera2 (NT2) cell model provides insight into the molecular mechanisms underlying HCMV ...
The histamine H(1) receptor (H1R) gene is up-regulated in patients with allergic rhinitis. However, the mechanism and reason underlying this up-regulation are still unknown. Recently, we reported that the H1R expression level is strongly correlated with the severity of allergic symptoms. Therefore, understanding the mechanism of this up-regulation will help to develop new anti-allergic drugs ...
The purpose of the present study was to further characterize the inhibition by prostaglandin E2 (PGE2) of adrenocorticotropin (ACTH) and beta-endorphin release from rat anterior pituitary fragments in vitro. Peptide hormone release was induced by vasopressin, which initiates secretion via cell surface receptors, or by secretagogues which can mimic various post-receptor mechanisms and the effect of ...
The generation of anaphylatoxins, particularly C5a, is important in extracorporeal circulation therapies such as granulocyte/monocyte apheresis, which activates the complement system and elevates C5a levels. However, no side effects of granulocyte/monocyte apheresis using cellulose acetate beads have been reported. To investigate the mechanism of complement activation, we ...
Short chain fatty acids (SCFAs) are fermentation products of anaerobic bacteria. More than just being an important energy source for intestinal epithelial cells, these compounds are modulators of leukocyte function and potential targets for the development of new drugs. The aim of this study was to evaluate the effects of SCFAs (acetate, propionate and butyrate) on production ...
Human recombinant tumor necrosis factor (TNF) was shown to be a weak direct stimulus of the neutrophil respiratory burst and degranulation. The stimulation, as measured by iodination, H/sub 2/O/sub 2/ production, and lysozyme release, was considerably increased by the presence of unopsonized zymosan in the reaction mixture, an effect which was associated with the increased ...
A study was conducted on the phosphorylation of proteins in the neutrophil cytosol in response to phorbol myristate acetate (PMA) and N-formyl-methionyl-leucyl-phenylalanine (fMLP). Autoradiography of gel electrophoretograms prepared from neutrophils incubated with /sup 32/P in the presence and absence of the activators showed nine ...
Luminol-dependent photonic burst from phorbol ester-treated single neutrophil was visually investigated by using an ultrasensitive photonic image intensifier microscope. Neutrophils stimulated by phorbol myristate acetate (0.1 microgram/ml) alone produced a negligible level of photonic activities in the presence of luminol (10 ...
The isoquinolinesulfonaminides 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H-7) and N-(2-aminoethyl)-5-isoquinolinesulfonamide (H-9) have previously been demonstrated to be potent inhibitors of cyclic nucleotide dependent kinases and protein kinase C while lacking calmodulin antagonist activity. The effects of these compounds on neutrophil functions were examined to ...
Patients whose cells are deficient in the glycoproteins LFA-1, Mo1, and p150,95 have recurrent infections and pronounced abnormalities in neutrophil adherence, aggregation, chemotaxis, and phagocytosis. Activation and regulation of oxidative metabolism of Mo1-deficient neutrophils have been characterized. These cells failed to depolarize or to produce ...
BackgroundRespiratory burst function resulting in the release of reactive oxygen species such as superoxide anion (O2-) from neutrophils is one of the key mechanisms of the innate immune system, and maladaptive control of this mechanism is thought to play a pivotal role in the development of pathologies such as acute lung injury ...
BackgroundThromboxane B2 (TXB2) and superoxide anion (O2-) are neuroinflammatory mediators that appear to be involved in the pathogenesis of several neurodegenerative diseases. Because activated-microglia are the main source of TXB2 and O2- ...
and PMA stimulation induce an ``oxidative burst'', characterized by a very intense, but brief reaction [97 than in T. cornutus hemocytes, and the kinetics of PMA-stimulated oxidative activity was different time a predominant mitochondrial origin of oxidative activity in gastropod hemocytes. * Corresponding
Live Newcastle disease virus (NDV) was used to investigate the in vitro effects of a viral infection on phagocytosis, chemiluminescence generation, superoxide production, oxygen consumption, NADPH-oxidase activity, and intracellular killing of bacteria by Ficoll-Hypaque separated human neutrophils. Phagocytosis of oil red O particles by NDV-treated PMN was inhibited by 50%. ...
Ca2+ entry through the capacitative (store-regulated) pathway was shown to be inhibited in neutrophil granulocytes by the protein kinase C activator phorbol 12-myristate 13-acetate and the chemoattractant N-formyl-methionyl-leucyl-phenylalanine (fMLP) by a hitherto unknown mechanism. Measuring both Ca2+ and Mn2+ entry into store-depleted cells we show in ...
Stimulation of intact human neutrophils with phorbol 12-myristate 13-acetate results in the selective phosphorylation of two cytoskeletal protein components with molecular masses of 20 and 48 kDa. After phosphorylation the 48-kDa protein is no longer recovered as a component of the cytoskeletal fraction but is present as a fully soluble phosphoprotein. ...
We studied the effects of oxidant stress on the catalase activity and hydrogen peroxide sensitivity of Neisseria gonorrhoeae. N. gonorrhoeae is an obligate pathogen of man that evokes a remarkable but ineffective neutrophil response. Gonococci make no superoxide dismutase but express high catalase activity. Gonococcal catalase activity increased threefold when organisms were ...
To simplify the isolation of neutrophils, we developed a one-step procedure using elutriation. The perfusate (0.2% gelatin and 0.1% glucose in phosphate buffered saline) was pumped through an elutriator rotor at 4 ml/min (25 degrees C) with the rotor speed at 2370 rpm. Twenty milliliters of anticoagulated porcine venous blood were mixed with 60 ml of perfusate and loaded into ...
Recent evidence has linked preterm premature rupture of the fetal membranes (PPROM) to placental abruption. Because neutrophils are a rich source of proteases that can degrade extracellular matrix in abruption-associated PPROM, we examined whether decidual neutrophil infiltration complicates abruption-associated PPROM. Accordingly, immunostaining for the ...
Human peripheral polymorphonuclear neutrophils exhibited potent cytotoxic activity against the dermatophyte fungi Tricophyton quinckeanum and T. rubrum as assessed by inhibition of fungal replication in Sabouraud's agar. Monocytes also showed cytotoxic activity, but this was less pronounced than that of neutrophils, while lymphocytes had no toxic effect. ...
We have previously shown that deuterium oxide (D/sub 2/O) enhances the oxidation of methionine, a myeloperoxidase (MPO) -mediated reaction, by human neutrophils during phagocytosis. However, D/sub 2/O has no effect on the oxidation of methionine by the purified MPO-H/sub 2/O/sub 2/-Cl- system. To explain this observation, we studied the effect of D/sub 2/O on the oxidative ...
Neutrophil extracellular traps (NETs) that bind invading microbes are pivotal for innate host defense. There is a growing body of evidence for the significance of NETs in the pathogenesis of infectious and inflammatory diseases, but the mechanism of NET formation remains unclear. Previous observation in neutrophils of chronic granulomatous disease (CGD) ...
When human blood neutrophils were incubated with immune complexes (consisting of IgG antibody) in the presence of platelets, there was a 2 to 10 fold enhancement in the generation of O-/sub 2/ and H/sub 2/O/sub 2/. This enhancement phenomenon was proportional to the dose of immune complex added and the number of platelets present. The response was not agonist specific since ...
Pasteurella haemolytica A1 leukotoxic culture supernatant was evaluated for its ability to cause aggregation of bovine peripheral neutrophils. Neutrophils were isolated by a hypotonic lysis method and incubated with zymosan-activated plasma (ZAP), leukotoxic culture supernatant, antileukotoxin serum, calcium and magnesium-free media, p-bromophenacyl ...
A novel approach to statistical analysis of flow cytometry fluorescence data have been developed and applied for population analysis of blood neutrophils stained with hydroethidine during respiratory burst reaction. The staining based on intracellular oxidation hydroethidine to ethidium bromide, which intercalate into cell DNA. Fluorescence of the resultant product serves as a ...
NASA Astrophysics Data System (ADS)
..gamma..-hexachlorocyclohexane was found to exert profound effects on the phosphatidylinositol cycle, cytosolic calcium level, and the respiratory burst of human neutrophils. Exposure of neutrophils prelabelled with /sup 32/P to 4 x 10/sup -4/ M ..gamma..-hexachlorocyclohexane almost tripled radioactivity in phosphatidic acid and correspondingly decreased ...
In the absence of antibiotic therapy, viable bacteria can persist within intra-abdominal abscesses in mice for at least 10 weeks. The mechanisms contributing to this survival are unknown, but abscess-derived neutrophils have impaired abilities to kill, in vitro, organisms engulfed in vivo. In order to determine whether subpopulations of abscess neutrophils ...