parvovirus B19; FABP, rat liver fatty acid binding protein; PPV, porcine parvovirus; M33, truncated version of the PPV-VP1 protein; PLA2, phospholipase A2; sPLA2, secreted PLA2; VP1up, the (N-terminal) unique part, with porcine ...
E-print Network
Phospholipase A2 (PLA2) is the rate limiting enzyme in the formation of prostaglandins and probably plays a key part in the pathology of various inflammatory diseases. In acute pancreatitis, the catalytic activity of PLA2 in serum correlates with the severity of the disease. The cellular source ...
PubMed Central
The ability of mammalian phospholipases A2 (PLA2) to hydrolyse cardiolipin (diphosphatidylglycerol) was monitored with a fluorescent displacement assay which allows the use of natural phospholipid substrates. The mammalian enzymes used were porcine pancreatic (Group I) secretory ...
PubMed
A variety of 2-oxoamides and related amides based on natural and non-natural amino acids were synthesized. Their activity on two human intracellular phospholipases (GIVA cPLA(2) and GVIA iPLA(2)) and one human secretory phospholipase (GV sPLA(2)) was ...
Recently, we purified to homogeneity and characterized a low-molecular-weight calcium-dependent phospholipase A2 (PLA2) from developing elm seed endosperm. This represented the first purified and characterized PLA2 from a plant tissue. The full sequences of two distinct but ...
Chicken pancreatic phospholipase A(2) (ChPLA(2)) was purified from delipidated pancreases using ammonium sulfate and ethanol precipitation, followed by sequential column chromatography steps on MonoQ Sepharose and size exclusion HPLC columns. ChPLA(2) was found to be a ...
High levels of interleukin 1 and tumor necrosis factor are found in both cases of malaria and cases of septic shock. Since both interleukin 1 and tumor necrosis factor induce expression of the proinflammatory enzyme phospholipase A2 (PLA2), we examined serum PLA2 levels in ...
Group II phospholipase A2 (PLA2) is a newly recognized antibacterial acute-phase protein. Recently we observed that transgenic mice expressing group II PLA2 (PLA2 ? mice) were able to resist experimental Staphylococcus aureus ...
Disulfide pairings and active site residues are highly conserved in secretory phospholipases A(2) (PLA(2)s). However, secretory PLA(2)s of marine invertebrates display some distinctive structural features. In this study, we report the isolation and ...
Phosphorothioate oligonucleotides were identified which directly inhibited human type II phospholipase A2 (PLA2) enzyme activity in a sequence specific manner. The minimum pharmacophore common to all oligonucleotides which inhibited PLA2 enzyme ...
A number of potent presynaptically-acting neurotoxins (PSNTXs) from snake venom were examined as regards the role of phospholipase A2 (PLA2) activity in altering acetylcholine (ACh) release and choline (Ch) uptake. Also, the effects of PSNTXs and snake ve...
National Technical Information Service (NTIS)
The low-molecular weight secretory phospholipase A2alpha (CssPLA2alpha) and beta (CsPLA2beta) cloned in this study exhibited diurnal rhythmicity in leaf tissue of Citrus sinensis. Only CssPLA2alpha displayed distinct diurnal ...
Fluidity is an important neuronal membrane property and it is influenced by the concentration of polyunsaturated fatty acids (PUFAs) in membrane phospholipids. Phospholipase A(2) (PLA(2)) is a key enzyme in membrane phospholipid metabolism, generating free PUFAs. In Alzheimer disease (AD), reduced ...
Of 10 mammalian secreted phospholipase A(2) (sPLA(2)) enzymes identified to date, group V and X sPLA(2)s, which are two potent plasma membrane-acting sPLA(2)s, are capable of preventing host cells from being infected with ...
Phospholipase A2 (PLA2) and reactive oxygen species have been implicated both individually and synergistically in various forms of cellular injury. The form(s) of PLA2 important for cell injury and the implications of enhanced activity of the enzyme, however, have not been discerned. Previous ...
A platelet aggregation inhibitor phospholipase A(2) (NND-IV-PLA(2)) was isolated from Naja naja (Eastern India) venom by a combination of cation and anion exchange chromatography. NND-IV-PLA(2) is the most catalytically active enzyme isolated from the ...
Chemical modification and inactivation of bovine pancreatic, porcine pancreatic, Naja naja atra and Pseudechis australis phospholipases A2 (PLA2s), belonging to Group I, and of Trimeresurus flavoviridis, Vipera russelli russelli and Agkistrodon halys blomhoffii PLA2s, ...
Geographic venom samples of Crotalus viridis viridis were obtained from South Dakota, Wyoming, Colorado, Oklahoma, Texas, New Mexico, and Arizona. From these samples, the phospholipases A(2) (PLA(2)s) were purified and their N-terminal sequences, precise masses, and in vitro enzymatic ...
of which may act as negative regulators of the active enzyme. Group VIA PLA2 has a consensus lipase motifDa protein that contains eight N-terminal ankyrin repeats and a consensus lipase motif Table 1 Properties acyl remodeling. The inhibition of Group VIA PLA2 mRNA translation with a Group VIA ...
Taipan snake venom, bee venom, Naja mossambica mossambica venom and porcine pancreas were obtained that various sPLA2s, including venom enzymes, human sPLA2-IIA, wild-type and catalytically inactive H48Q mutant, Germany), heparinase-1 was from Sigma (Deisenhofen, Germany), and all other chemicals used were from
The ability of Lys49 and Asp49 phospholipases A(2) (PLA(2)), from Bothrops asper snake venom, to cause hyperalgesia was investigated in rats, using the paw pressure test. Intraplantar injection of both toxins (5-20 micro g/paw) caused hyperalgesia, which peaked 1h after injections. Incubation of both proteins with ...
Different mammalian secreted phospholipases A(2) (sPLA(2) s) are expressed in male reproductive organs and/or in sperm cells but their cellular functions are still not fully characterized. Because several reports indicate a link between cellular lipids and sperm motility, we have investigated the effect of mouse ...
The rabbit neutrophil phospholipase A2 (PLA2) degrades the phospholipids of E. coli killed by a bactericidal protein purified from the rabbit neutrophil. Of nine other PLA2 examined four were inactive, four produced low levels of hydrolysis, and one, the basic isozyme of ...
Energy Citations Database
. Thus, the surface concentration in mole fraction, not the bulk concentration in molarity, best reflects. Inhibitory Activity of 2-Oxoamides against GIVA PLA2 a 0.01 mole fraction. b 0.02 mole fraction. c 0.05 mole--norleucine was the most potent inhibitor, causing a 50% decrease in GIVA PLA2 ...
This study was designed to elucidate the signalling pathways by which secretory phospholipases A2 (sPLA2s) induce in vitro neutrophil migration. The cell migration assays were performed with Naja mocambique venom PLA2 (sPLA2 with ...
Many isolated compounds from endophytic fungus have been useful to human beings, mainly those with medicinal applications and particularly those that can be used in inflammatory processes. Trichoderma fungi produce substances known as koninginins that have great structural similarity to compounds like flavonoids and vitamin E, which are able to inhibit the phospholipase ...
When soluble and particulate fractions of human platelet homogenate were chromatographed on DEAE-cellulose and hydroxylapatite columns, total phospholipase A2 (PLA2; phosphatide 2-acylhydrolase, EC 3.1.1.4) activity increased sharply. PLA2 ...
We previously reported that PLA(2) activity in the gills is higher than that in other tissues in red sea bream and purified PLA(2) from the gills belongs to the group IB PLA(2) as well as other red sea bream PLA(2)s. In this study, we reconfirmed that ...
Soluble phospholipase A2 (PLA2) purified from rheumatoid synovial fluid (group II) and repurified Naja naja venom PLA2 (group I) were compared for their influence on phagocytic activity of human polymorphonuclear (PMN) and mononuclear (MO) phagocytes. ...
Polychlorinated biphenyls (PCBs) are a group of persistent and widespread environmental pollutants, and known to affect signaling molecules. Phospholipase A2 (PLA2) mediates cellular destructive processes as well as normal physiological responses in neuronal cells. In this study, we examined whether ...
The microtubule-associated protein Tau promotes the assembly and stability of microtubules in neuronal cells. Six Tau isoforms are expressed in adult human brain. All six isoforms become abnormally hyperphosphorylated and form neurofibrillary tangles in Alzheimer disease (AD) brains. In AD, reduced activity of phospholipase A(2) ...
The Group VIA Phospholipase A(2) (iPLA(2)beta) is the first recognized cytosolic Ca(2+)-independent PLA(2) and has been proposed to participate in arachidonic acid (20:4) incorporation into glycerophosphocholine lipids, cell proliferation, exocytosis, apoptosis, and other ...
Group IIA secretory phospholipases A(2) (sPLA(2)-II) is generally known to display potent gram-positive bactericidal activity, while group IA sPLA(2) (sPLA(2)-I) reportedly is not. In this work, a novel ...
The development of selective inhibitors for individual PLA(2) enzymes is necessary in order to target PLA(2)-specific signaling pathways, but it is challenging due to the observed promiscuity of known PLA(2) inhibitors. In the current work, we present the development and ...
The mechanisms by which glutamatergic neurotransmitters modulate neuronal lipid metabolism are not well established. We have directly measured phospholipase A2 (PLA2) enzymic activity in cell-free extracts from cortical neuronal cultures from rat brain and have found that the PLA2 ...
Phospholipases A(2) (PLA(2)s) are essential enzymes in cells. They are not only responsible for maintaining the structural organization of cell membranes, but also play a pivotal role in the regulation of cell functions. Activation of PLA(2) s results in the release of fatty acids and ...
Five new bioactive sesterterpenes (1-5) have been isolated from the New Caledonian marine sponge Petrosaspongia nigra Bergquist and named petrosaspongiolides M-R. Their chemical structures were determined from 1D and 2D NMR studies and MS data. All compounds inhibited different preparations of phospholipase A2 ...
Phospholipase A2 (PLA2) activity was investigated in various tissues of male and female red sea bream. In both male and female fishes, the specific activity of PLA2 in the gills was 70 times higher than that in other tissues, such as the adipose tissue, intestine, and ...
The effects of several calcium antagonists on phospholipase A2 (PLA2) activity were examined. Nifedipine and nisoldipine inhibited a cell-free preparation of PLA2 in a dose-dependent manner with maximal inhibition of 71-77% observed at 100 microM. More potent or equipotent dihydropyridine ...
Lipoprotein-associated Phospholipase A2 (Lp-PLA(2)) is an enzyme that belongs to the A2 Phospholipase superfamily and is produced by inflammatory cells that are involved in the process of atherogenesis. Even though there is controversy in current bibliography whether ...
Results from high-performance liquid chromatography/nano-electrospray ionization tandem mass spectrometry (HPLC/nESI-MS/MS) coupled to two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (2D SDS-PAGE) indicated that the monomer and dimer of phospholipase A(2) (PLA(2)) coexisted in crude ...
Naegleria fowleri, a free-living amoeba, is the causative agent of primary amoebic meningoencephalitis. Previous reports have demonstrated that N. fowleri expresses one or more forms of phospholipase A(2) (PLA(2)) and that a secreted form of this enzyme is involved in pathogenesis. However, the molecular nature of ...
Rabbit antibodies were prepared against purified phospholipase A2 (NN-XIa-PLA2) from Indian cobra (Naja naja naja) venom. The PLA2 has haemolytic, neurotoxic, myotoxic, cytotoxic and oedema-inducing activities apart from the catalytic activity. The immunological ...
Bilirubin is a powerful antioxidant that suppresses the inflammatory process. However its interaction with proinflammatory PLA(2) enzyme is not known. Inhibition of several secretory phospholipase A(2) (sPLA(2)) enzyme activities by bilirubin was ...
Human group IIA-secreted phospholipase A(2) (sPLA(2)-IIA) is an important regulator of cytokine-mediated inflammatory responses in both in vitro and in vivo models of rheumatoid arthritis (RA). However, treatment of RA patients with sPLA(2)-IIA inhibitors shows only transient benefit. Using an ...
Secretory phospholipase A(2)s (sPLA(2)) hydrolyze glycerophospholipids to liberate lysophospholipids and free fatty acids. Although group X (GX) sPLA(2) is recognized as the most potent mammalian sPLA(2) in vitro, its precise ...
In ovarian cancer, the molecular targeted chemotherapeutics could increase the efficiency of low-dose radiotherapy while decreasing injury to adjusted organs. In irradiated A2780 human ovarian carcinoma cells, cytosolic phospholipase A2 (cPLA(2)) inhibitor AACOCF(3) prevented activation of ...
Polyclonal antiserum was prepared against phospholipase A2 from Naja naja and used to prepare a purified antibody. It cross-reacted with the antigen, and with intracellular mammalian PLA2. This antibody was immunoreactive and inhibited the PLA2 activity of Naja naja and of guinea pig alveolar ...
BackgroundThe presence of chicken group-IIA PLA2 (ChPLA2-IIA) in the intestinal secretion suggests that this enzyme plays an important role in systemic bactericidal defence. We have analyzed the bactericidal activity of purified ChPLA2-IIA, on several ...
We propose that expression of four genes encoding secretory phospholipases A(2) (sPLA(2)) mediates insect nodulation responses to bacterial infection. Nodulation is the quantitatively predominant cellular defense reaction to bacterial infection. This reaction is mediated by eicosanoids, the biosynthesis of which ...
The ability of human group IIa secreted phospholipase A(2) (human sPLA(2)) to hydrolyse the phospholipid membrane of whole cell suspensions of Gram-positive bacteria is demonstrated in real time using a continuous fluorescence displacement assay. Micrococcus luteus is used as a model system and demonstrates an ...
IL-1 stimulates mesangial cells to synthesize specific proteins, including a non-pancreatic (Type II) phospholipase A2 (PLA2). We have studied the regulation of PLA2 by proinflammatory mediators, implicated in the pathogenesis of glomerulonephritis, and have assessed whether the activation of ...
Platelet activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is known to be present in excess in psoriatic skin, but its exact role is uncertain. In the present study we demonstrate for the first time the role of group VI PLA(2) in PAF-induced arachidonic acid release in highly differentiated human keratinocytes. ...
Activation of phospholipase A2 (PLA2) by the aggregation of receptors for immunoglobulin E (IgE) can be studied in streptolysin O-permeabilized rat basophilic leukemia cells. Under these conditions, 40 microM guanosine 5'-O-(3-thio)triphosphate (GTP gamma S) stimulates ...
A comparative molecular dynamics simulation of free and inhibitor-bound form of secretory phospholipase A(2) (sPLA(2)) of Russell's viper discloses the sort of restrictions in active site for inhibitor binding and implies suitable sites for further design of inhibitors based on ...
Stimulation of rabbit articular chondrocytes with interleukin 1 (IL-1) results in the activation of intracellular phospholipase A2 (PLA2) and the subsequent secretion of this enzyme into the extracellular milieu. Pretreatment of chondrocytes with actinomycin D or cycloheximide significantly ...
Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is an enzyme which binds to oxidized LDL and has a pro-inflammatory role in the pathogenesis of atherosclerosis. The Lp-PLA(2) Studies Collaboration showed the relationship between Lp-PLA(2) levels and ...
Human cytomegalovirus (HCMV) is known to carry host cell-derived proteins and mRNAs whose role in cell infection is not understood. We have identified a phospholipase A2 (PLA2) activity borne by HCMV by using an assay based on the hydrolysis of fluorescent phosphatidylcholine. This ...
An entomopathogenic bacterium, Xenorhabdus nematophila, induces an immunosuppression of target insects by inhibiting phospholipase A(2) (PLA(2)) activity. Recently, an immune-associated PLA(2) gene was identified from the red flour beetle, Tribolium ...
Phospholipase A2 (EC 3.1.1.4; PLA2) activity in wheat (Triticum aestivum L.) crown tissue from plants undergoing cold acclimation and/or chilling stress was investigated in a moderately cold tolerant winter wheat, a spring wheat, and a poorly cold tolerant winter wheat. ...
Technology Transfer Automated Retrieval System (TEKTRAN)
Mast cells release a variety of mediators including arachidonic acid (AA) metabolites to regulate allergy, inflammation and host defense, and their differentiation and maturation within extra-vascular microenvironments depends on the stromal cytokine stem cell factor. Mouse mast cells express two major intracellular phospholipase A2s ...
It has been recognized that phospholipase A(2) (PLA(2)) is a crucial factor of snake venom induced inflammation. Recently, promutoxin, a novel member of minor subgroup of snake venom PLA(2) (R49 PLA(2)) has been characterized in our ...
Integrins are essential in the complex multistep process of angiogenesis and are thus attractive targets for the development of antiangiogenic therapies. Integrins are antagonized by disintegrins and C-type lectin-like proteins, two protein families from snake venom. Here, we report that CC-PLA2-1 and CC-PLA2-2, two novel secreted phospholipases A(2) ...
Bee venom phospholipase A2 (bvPLA2) is a prototypic group�III enzyme which consists of unique N-terminal and C-terminal domains and a central secretory PLA2 (sPLA2) domain. This sPLA2 domain is highly homologous with human ...
for Arachidonic Acid Release in P388D1 Macrophages1 Mari�a A. Balboa, Jesu�s Balsinde, and Edward A. Dennis2 one PLA2 participates in this process (3). In P388D1 macrophages, two different PLA2s, namely; ERK, extracellular signal- regulated kinase (p42/p44 MAPK); MAPK, mitogen-activated ...
Cytosolic phospholipase A(2)? (cPLA(2)?) is the most widely studied member of the Group IV PLA(2) family. The enzyme is Ca(2+)-dependent with specificity for phospholipid substrates containing arachidonic acid. As the pinnacle of the arachidonic acid pathway, ...
Phospholipase A(2) (PLA(2)) catalyses the hydrolysis of the sn-2 position of glycerophospholipids to yield fatty acids and lysophospholipids. So far, more than 30 enzymes that possess PLA(2) or related activity have been identified in mammals. About one ...
Phospholipases A(2) (PLA(2)s) are enzymes that cause the liberation of fatty acids and lysophospholipids by the hydrolysis of membrane phospholipids. In addition to their catalytic action, a wide variety of pharmacological activities have been described for snake-venom ...
Activation of phospholipase A2 (PLA2) by the aggregation of receptors for immunoglobulin E (IgE) can be studied in streptolysin O-permeabilized rat basophilic leukemia cells. Under these conditions, 40 micrograms guanosine 5'-O-(3-thio)triphosphate stimul...
This work investigates the metabolic origin of triacylglycerol (TAG) formed during lipid droplet (LD) biogenesis induced by stress. Cytotoxic inhibitors of fatty acid synthase induced TAG synthesis and LD biogenesis in CHO-K1 cells, in the absence of external sources of fatty acids. TAG synthesis was required for LD biogenesis and was sensitive to inhibition and down-regulation of the expression ...
Type A2 phospholipase (PLA2) activity has been observed in integral membrane protein extracts of Schistosoma japonicum. Antiserum raised against bee venom PLA2 recognized a single 16-kDa band in the parasite extracts; it also localized to antigen in the ...
Indian cobra venom contains many phospholipase A2 (PLA2) toxins. In the present study two toxic PLA2s have been purified from the Indian cobra (Naja naja naja) venom by column chromatography. The NN-XIa-and NN-XIb-PLA2s have mol. ...
We recently suggested a novel mechanism for the activation of phospholipase A2 (PLA2), with a (catalytically) highly active oligomeric state, which subsequently becomes inactivated by conversion into amyloid. This process can be activated by ...
OBJECTIVE: We investigated an association between lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) activity, inflammation, and oxidative stress in women with metabolic syndrome (MS). METHODS: We performed a case-control study in MS women (n=368) and non-MS women (n=854). ...
Phospholipase A2 (PLA2) activity has been suggested to mediate some of the tumor necrosis factor (TNF) induced cellular responses including cytotoxicity. We evaluated the induction of both the 85-kDa cytosolic phospholipase A2 ...
NADPH oxidase Nox2 is involved in the production of superoxide by rheumatoid synovial cells, constitutively and after pro-inflammatory cytokine treatment. The aims of the study were to evaluate the capacity of these cells to produce the superoxide anion in response to arachidonic acid (AA), and to study the involvement of cytosolic phospholipase A(2) ...
An apical-enriched plasma membrane fraction (A-PM) was prepared from rat parotid gland by Mn2+ precipitation. In this fraction, phosphatidylcholine (PC) labelled at the sn-2 position was mainly decomposed into two labelled compounds (free fatty acid and 1,2-diacylglycerol) under Ca2+-free conditions. Studies using double-labelled PC and 2,3-diphosphoglycerate (as a phospholipase D inhibitor) ...
Alveolar epithelial type II cells (AT II) in which lung surfactant synthesis and secretion take place, are subjected to low magnitude stretch during normal breathing. The aim of the study was to explore the effect of mild stretch on phospholipase A(2) (PLA(2)) activation, an enzyme known to be ...
We show that ethyl 2-oxo-2H-chromene-3-carboxylate (EOCC), a synthetic coumarin, irreversibly inhibits phospholipase A(2) (sPLA2) from Crotalus durissus ruruima venom (sPLA2r) with an IC(50) of 3.1 +/- 0.06 nmol. EOCC strongly decreased the V(max) and K(m), and it virtually ...
Among mammalian secreted phospholipases A2 (sPLA2s), group X sPLA2 has the most potent hydrolyzing activity toward phosphatidylcholine and is involved in arachidonic acid (AA) release. Group X sPLA2 is produced ...
Two anti-inflammatory peptides (antiflammins) corresponding to a high amino acid similarity region between lipocortin I and uteroglobin were tested for their ability to inhibit purified human synovial fluid phospholipase A2 (HSF-PLA2). No inhibitory activity was observed, even at such high ...
The genome of the sea anemone Nematostella vectensis (Nv) (Cnidaria, Anthozoa) was sequenced recently (Putnam et al., Science 317: 86, 2007). In the current study, 22 proteins of Nv were identified as putative phospholipases A(2) (PLA(2)) that showed up to 40-50% sequence identity with secreted or intracellular ...
The present study evaluated the neurotoxic potential of phospholipase A2 (PllA2) in in vitro (primary neuronal cultures) and in vivo (EEG and behavior) rat models of CNS excitability. In vitro, PLA2 (0.0038-5.3 nM) or melittin (a potent activator of ...
Recent studies suggest that CNS phospholipase A(2) (PLA(2)) isoforms play a role in nociception, but until now, direct evidence of increased brain PLA(2) activity during allodynia or hyperalgesia is lacking. The present study was carried out, using ...
Secretory phospholipases A2 (PLA2) from Naja naja naja (cobra snake) venom, from Bothrops neuwiedii (crotalid snake) venom (two isoforms) and from bee venom were modified with tresylated monomethoxy poly(ethylene glycol) (TMPEG). The kinetic and inflammatory properties of the adducts ...
Indole-5-carboxylic acids with 3-aryloxy-2-oxopropyl residues in position 1 have been found to be potent inhibitors of human cytosolic phospholipase A(2)? (cPLA(2)?). In course of structure-activity relationship studies, we investigated the effect of the substitution of the electrophilic ketone ...
We previously reported that gill group IB secretory phospholipase A(2) (sPLA(2)) exists as an inactive pro-sPLA(2) with the dipeptide Ala-Arg, at the N-terminus of mature sPLA(2) in mucous cells. ...
This paper reports the purification and biochemical/pharmacological characterization of two myotoxic phospholipases A(2) (PLA(2)s) from Bothrops brazili venom, a native snake from Brazil. Both myotoxins (MTX-I and II) were purified by a single chromatographic step on a CM-Sepharose ion-exchange column up to a high ...
This study investigates the ways in which two proinflammatory cytokines, tumor necrosis factor alpha (TNF) and interleukin-1 beta (IL1), cause increased production of prostaglandin E2 (PGE2) in rabbit articular chondrocytes (RAC). Rabbit articular chondrocytes in primary culture were incubated with IL1, TNF, or both. Arachidonic acid (AA) release, PGE2 production, and the ...
Surfactin inhibits platelet and spleen cytosolic 100 kDa phospholipase A2 (PLA2). In contrast, this same compound enhances rat platelet group II PLA2 activity by approximately 2-fold and slightly increases group I ...
We have recently shown that the major proteins of bovine seminal plasma, namely BSP-A1, BSP-A2, BSP-A3 and BSP-30-kDa (collectively called BSP proteins) bind to spermatozoa and that the binding sites on the plasma membrane of spermatozoa are choline phospholipids. In view of the fact that these phospholipids are substrates for phospholipase ...
The bioresponsive conjugate dextrin-phospholipase A2 (PLA2) is a novel anticancer polymer therapeutic. Dextrin conjugation decreases PLA2 bioactivity, but this can be restored following triggered degradation by alpha-amylase. The conjugate displays reduced hemolytic ...
To investigate the peculiar absence of phospholipases A(2) (PLA(2)s) in most Crotalus horridus (CH) venom, we cloned and sequenced the venom PLA(2)s of three CH specimens from different regions. The results revealed that all the venom glands contained mRNAs that encoded an ...
Large amounts of type II-secreted phospholipase A2 (type II sPLA2) are secreted into inflammatory synovial fluid and they are believed to induce the synthesis of lipid mediators by articular chondrocytes. Preliminary experiments showed that insulin-like growth factor-I, which counteracts cartilage degradation in ...
Genetic knockout of hormone-sensitive lipase in mice has implicated the presence of other intracellular triacylglycerol (TAG) lipases mediating TAG hydrolysis in adipocytes. Despite intense interest in these TAG lipases, their molecular identities thus far are largely unknown. Sequence data base searches for proteins containing calcium-independent phospholipase ...
The goal of the present study is to elucidate the effect of lipid domain formation on activities of Naja naja atra and Bungarus multicinctus phospholipase A(2) (PLA(2)) enzymes. Sphingomyelin inhibited enzymatic activity and membrane-damaging activity ...
CM-Sephadex C-25 column chromatography profile of Indian cobra (Naja naja) venom from eastern region showed a distinct and a dominant phospholipase peak, peak-10, while it was not seen in either southern or western venom samples. Peak-10 was subjected to CM-Sephadex C-25 and Sephadex G-50 column chromatography to isolate NN-X-PLA(2). ...
In the Cryptosporidium parvum-infected intestinal epithelial cell, the parasite occupies an unusual extracytoplasmic location at the luminal surface, but how the invading zoites interact with the host cell to achieve this niche is poorly understood. This study examined the role of secretory phospholipase A(2) ...
We investigated whether the presence of endogenous or exogenous lipoprotein-associated phospholipase A2 (Lp-PLA2) can modify the cellular association of oxidized low density lipoprotein (oxLDL) and oxidized lipoprotein(a) (oxLp(a)) by human monocyte-derived macrophages (MDM) and hepatocytes (HepG2). Purified ...
Platelet-activating factor (PAF) production is carefully controlled in inflammatory cells. The specific removal of arachidonate (AA) from 1-O-alkyl-2-arachidonoyl-sn-glycero-3-phosphocholine (GPC), thought to be mediated by CoA-independent transacylase (CoA-IT), is required to generate the PAF precursor 1-O-alkyl-2-lyso-GPC in human neutrophils. Exposure of A23187-stimulated ...
We showed in an earlier study (Arita, H., Hanasaki, K., Nakano, T., Oka, S., Teraoka, H., and Matsumoto, K. (1991) J. Biol. Chem. 266, 19139-19141) that there is a high affinity and specific binding site for mammalian group I phospholipase A2 (PLA2-I) in Swiss 3T3 fibroblast cells. Analysis of the cellular ...
We investigated the ability of the sPLA(2), known as MT-III, isolated from the viperid snake Bothrops asper, to induce LB formation in macrophages and the major cellular signaling pathways involved in this process. The effects of MT-III on ADRP localization and expression and macrophage ultrastructure were assessed. Our results showed that this sPLA(2) induced a marked increase in LB numbers in ...
The marine product ircinin has been tested for its effects on secretory and cytosolic phospholipase A2 (PLA2) activities in vitro as well as for inhibition of cellular functions in human neutrophils and inflammatory responses in mice. Ircinin inhibited Naja naja venom, human synovial ...
Association of class-II phospholipase A(2) (PLA(2)) with aggregated phospholipid substrate results in elevated levels of the Ca(2+)-dependent hydrolytic activity. The Asp49 residue participates in coordination of the Ca(2+) ion cofactor, however, in Lys49-PLA(2) homologues ...
A post-synaptic neurotoxic phospholipase A(2) (PLA(2)) has been purified from Indian cobra Naja naja venom. It was associated with a peptide in the venom. The association was disrupted using 8 M urea. It is denoted to be a basic protein by its behavior on both ion exchange chromatography and electrophoresis. It is ...
Secreted phospholipase A(2)s form a large family of proteins involved in diverse biological and pathophysiological processes. Group IIE secreted phospholipase A(2) (sPLA(2)-IIE) is one of the latest discovered members of this family. Previous studies revealed that the ...
The bacterium, Xenorhabdus nematophila, is a virulent insect pathogen. Part of its pathogenicity is due to impairing cellular immunity by blocking biosynthesis of eicosanoids, the major recognized signal transduction system in insect cellular immunity. X. nematophila inhibits the first step in eicosanoid biosynthesis, phospholipase A2 ...
NASA Astrophysics Data System (ADS)
This work aimed at the isolation and structural/functional characterization of a phospholipase A(2) (CgPLA(2)) from the extract of the anemone Condylactis gigantea. CgPLA(2) was isolated with a high purity level through three chromatographic steps, showing pI 8.6 and ...
The Transient Receptor Potential Canonical 5 (TRPC5) protein forms calcium-permeable cationic channels that are stimulated by G protein-coupled receptor agonists. The signaling pathways of such agonist effects are poorly understood. Here we investigated the potential for involvement of lysophosphatidylcholine (LPC) and arachidonic acid generated by group 6 (GVI) phospholipase ...
Eicosanoids are a broad family of lipids that play a critical role in host defense against bacterial and fungal infections. The first enzyme in the metabolic pathway for the generation of eicosanoids is group IVA phospholipase A(2), also known as cytosolic phospholipase A(2)alpha ...
Phospholipase A2 (PLA2) activity was purified 12,544-fold with a 13% yield from the plasma of patients diagnosed of septic shock by the sequential use of heparin-agarose affinity chromatography, gel filtration, and reverse-phase f.p.l.c. Gel-filtration chromatography of plasma omitting ...
The biologically active phospholipid platelet activating factor (1-O-alkyl-sn-glycero-3- phosphocholine, PAF), a phospholipase A2 (PLA2) product, is involved in excitatory neurotransmitter (i. e. Glutamate) release and synaptic plasticity (Bazan et al. ,1...
Casearia sylvestris (Flacourtiaceae) is a plant which grows in the wild. The crude extract and pure substances from this plant induced partial inhibition of the PLA: (phospholipase A2) activity of snake venoms and some purified toxins. C. sylvestris extract efficiently neutralized the hemorrhagic and myotoxic ...
Phospholipid metabolizing enzymes are important participants in neutrophil signal transduction pathways. The methods discussed herein describe assays for assessing the activities of phospholipase (PL)A2, PLC, PLD, and phosphoinositide 3-OH-kinase (PI3-K) in intact neutrophils. PLA2 ...
Snake venoms contain multimolecular forms of phospholipase A2 which are diverse with respect to their pharmacological properties. A neurotoxic PLA2 from Naja naja naja venom has been purified in two steps. (1) The whole venom was fractionated on CM-Sephadex C-25 column; 4.6% of the total ...
Cytosolic phospholipase A2? (cPLA2?) and fatty acid amide hydrolase (FAAH) are enzymes that have emerged as attractive targets for the development of analgesic and anti-inflammatory drugs. We recently reported that 1-[3-(4-octylphenoxy)-2-oxopropyl]indole-5-carboxylic acid (5) is a dual inhibitor of cPLA2? and ...
The marine product variabilin was identified as a novel inhibitor of phospholipase A2 (PLA2), which exhibited IC50 values of 6.9 microM and 7.9 microM for human synovial secretory PLA2 and U937 cells cytosolic PLA2 ...
Exposure to environmental pollutants, such as polycyclic aromatic hydrocarbons (PAHs) found in coal tar mixtures and tobacco sources, is considered a significant risk factor for the development of heart disease in humans. The goal of this study was to determine the influence of PAHs present at a Superfund site on human coronary artery endothelial cell (HCAEC) phospholipase ...
Oxidation and lipolytic remodeling of LDL are believed to stimulate LDL entrapment in the arterial wall, expanding the inflammatory response and promoting atherosclerosis. However, the cellular responses and molecular mechanisms underlying the atherogenic effects of lipolytically modified LDL are incompletely understood. Human THP-1 monocytes were prelabeled with [(3)H]arachidonic acid (AA) before ...
We examined the role of IFN gamma in protection against Toxoplasma gondii in the monocytoid cell line THP1. The addition of IFN gamma to cultured infected THP1 cells reduced the number of parasitized cells without altering intracellular multiplication during the first 24 hr. This reduction was potentiated by bacterial lipopolysaccharide (LPS). We also examined the role of an enzyme important for ...
A cDNA that codes for human rheumatoid synovial fluid phospholipase A2 (PLA2) hybridized with a RNA of the same size (900 base pairs) isolated from rabbit articular chondrocytes (RAC). Treatment of RAC with 100 ng/ml recombinant human interleukin-1 beta (IL-1) for 24 hours caused a 13-fold increase in mRNA for this ...
The extracellular phospholipase A2s (PLA2) from cobra venom, rattlesnake venom, and porcine pancreas were analyzed by radiation inactivation to determine their functional aggregation states. The analysis was performed in the presence of the protein transferrin at two different concentrations of PLA2: 5 ...
Secretory phospholipases A(2) (sPLA(2)s) are a subfamily of lipolytic enzymes which hydrolyze the acyl bond at the sn-2 position of glycerophospholipids to produce free fatty acids and lysophospholipids. These products are precursors of bioactive eicosanoids and platelet-activating factor ...
Our previous works have elucidated that the 12-lipoxygenase pathway is directly implicated in glutamate-induced neural cell death, and that such that toxicity is prevented by nM concentrations of the natural vitamin E alpha-tocotrienol (TCT). In the current study we tested the hypothesis that phospholipase A(2) ...
Mechanisms underlying the role of lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) in atherosclerotic development are not completely understood. We evaluated the relationship of Lp-PLA(2) with endothelial dysfunction, an early manifestation of atherosclerosis, in a cohort without known clinical cardiovascular ...
In several neurodegenerative diseases of the CNS, oligodendrocytes are implicated in an inflammatory process associated with altered levels of oxysterols and inflammatory enzymes such as secreted phospholipase A2 (sPLA2). In view of the scarce literature related to this topic, we investigated oxysterol effects on ...
... Preparation of Rat Uterine Tissue Homogenates Uterine tissue (myometrium with attached endometrium) was excised from Gestation Day ( ... to assay myometrial PLA2 activity. Frozen uterine tissue (myometriu...
NBII National Biological Information Infrastructure
Eur J Clin Invest 2011; 41 (8): 820-827 ABSTRACT: Background? A recent meta-analysis showed that both plasma lipoprotein-associated phospholipase A(2) (Lp-PLA(2) ) mass and activity independently predict cardiovascular events. Notably, Lp-PLA(2) ...
End-stage renal disease (ESRD) patients exhibit increased in vivo oxidative stress conceivably contributing to cardiovascular mortality. The type IIA secretory phospholipase A(2) (sPLA(2)) has proatherogenic activity. We explored the hypothesis that sPLA(2) contributes to oxidative stress ...
Although perturbed lipid metabolism can often lead to skin abnormality, the role of phospholipase A(2) (PLA(2)) in skin homeostasis is poorly understood. In the present study we found that group X-secreted PLA(2) (sPLA(2)-X) was ...
We report that Group IVA cytosolic phospholipase A2 (PLA2G4A) is important in the development and function of rodent testes. Interstitial cells of rat testes had high PLA2 activity that was very sensitive to the PLA2G4A-preferential inhibitor AACOCF3. ...
K(+)-Cl(-)-cotransport (KCC) has been reported to have various cellular functions, including proliferation and apoptosis of human cancer cells. However, the signal transduction pathways that control the activity of KCC are currently not well understood. In this study we investigated the possible role of phospholipase A(2) ...
In the current work, the pathways are presented and reviewed showing how adenosine acts on the production and release of arachidonic acid (AA) in activated human monocytes by the involvement of various phospholipase A2 (PLA2) and protein kinase C (PKC) enzymes in physiological (normal) ...
A homodimeric acidic PLA(2) (RVVA-PLA(2)-I) of 58.0�kDa molecular weight purified from Russell's viper (Daboia russelli) venom demonstrated dose-dependent catalytic, strong anticoagulant and indirect hemolytic activities and inhibited blood coagulation cascade in both enzymatic and ...
Two cDNA encoding red sea bream DE-1 and DE-2 phospholipases A2 (PLA2) were cloned from the hepatopancreas of red sea bream, Pagrus (Chrysophrys) major. The cDNA of DE-1 PLA2 encoded a mature protein of 125 amino acid residues with an apparent signal peptide of 20 residues ...
Turmerin is a protein from Turmeric (Curcuma longa L.) with a relative molecular mass of 14 kDa. The protein inhibits the enzymatic activity and neutralizes the pharmacological properties, such as cytotoxicity, oedema and myotoxicity of multitoxic phospholipase A2 (NV-PLA2) of cobra (Naja naja) ...
Thorough control of risk factors is pivotal for cardiocerebrovascular diseases. As classic risk assessment accounts for only 50% of risk variability and due to the role of inflammatory processes in endothelial dysfunction and atherosclerotic plaque rupture, it is necessary to identify new biomarkers for risk prediction. In addition to the inflammatory marker high sensibility C-reactive protein ...
Cytosolic phospholipase A(2)-alpha (cPLA(2)-alpha) is a calcium-sensitive enzyme involved in receptor-mediated eicosanoid production. In resting cells, cPLA(2)-alpha is present in the cytosol and nucleus and translocates to membranes via its calcium-dependent lipid-binding ...
Abstract Background: The clinical relevance of serum lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) in populations prone to cardiometabolic risk needs exploration. We determined major covariates of Lp-PLA(2) mass, and its associations with cardiometabolic disorders. Methods: In 736 Turkish adults, serum ...
a simple gas chromatographic method for the assay of phospholipase A2 (PLA2) has been described in which arachidonic acid released from endogenous phospholipid pools is measured following its extraction and derivatization to pentafluorobenzyl esters. Using this assay, PLA2 ...
Phospholipase A2 (PLA2; phosphatide 2-acylhydrolase, EC 3.1.1.4) activity from human platelets increases significantly when the enzyme is separated from an endogenous inhibitor(s). The inhibitor, associated mainly with a particulate fraction, has now been identified as a mixture of unsaturated ...
Group IVA cytosolic phospholipase A(2)alpha (cPLA(2)alpha) plays a role in the microbicidal machinery of immune cells by translocating to phagosomes to initiate the production of antimicrobial eicosanoids. In this work, we have studied the involvement of the cationic cluster of cPLA(2)alpha ...
phosphorylation of p38 MAPK, two key regulators of COX-2 protein expression, but does activate the ERK1/2 pathway.jbc.orgDownloadedfrom #12;2 Macrophages from Group V sPLA2 (sPLA2-V)- deficient mice show impaired production of both COX (Santa Cruz, #sc-535), 33 ng/mL, anti-human phospho- ERK ...
Accumulation and modification of low density lipoproteins (LDL) within the vessel wall represent key events in atherogenesis. Secretory phospholipase A2 type IIA (sPLA2-IIA) modulates the enzymatic process of LDL-modification and was recently identified as an independent predictor of coronary events in patients ...
Increased plasma creatine kinase-myoglobin (CK-MB) occurs in patients with acute myocardial infarction (AMI), but its underlying relationship with cytosolic phospholipase A2 (cPLA2) is poorly understood. In the present study we sought to determine cPLA2 ...
BACKGROUND--Bacterial lipopolysaccharide (LPS) has been proposed to participate in the pathogenesis of pancreatic inflammatory disease. AIMS--This study investigated the role of endotoxaemia in the pathogenesis of pancreatic acinar cell injury. METHODS--Sixty eight male Spraque-Dawley rats were used in the study. Escherichia coli LPS (5 mg/kg) was injected into the peritoneal cavity of the rats. ...
This study determined the in vitro inhibitory effects of cocoa extracts and procyanidins against pancreatic ?-amylase (PA), pancreatic lipase (PL), and secreted phospholipase A(2) (PLA(2)) and characterized the kinetics of such inhibition. Lavado, regular, and Dutch-processed cocoa extracts as well as cocoa ...
In the present study, an acidic PLA(2), designated Bl-PLA(2), was isolated from Bothrops leucurus snake venom through two chromatographic steps: ion-exchange on CM-Sepharose and hydrophobic chromatography on Phenyl-Sepharose. Bl-PLA(2) was homogeneous on SDS-PAGE and when ...
Pancreatic phospholipase A(2) (PLA(2)) plays an important role in cellular homeostasis as well as in the process of carcinogenesis. Effects of metallo-drugs used as chemotherapeutics on the activity of this enzyme are unknown. In this work, the interaction between porcine pancreatic ...
Phospholipases A2 (PLA2) comprise a set of extracellular and intracellular enzymes that catalyze the hydrolysis of the sn-2 fatty acyl bond of phospholipids to yield fatty acids and lysophospholipids. The PLA2 reaction is the primary pathway through which arachidonic acid (AA) is released from phospholipids. ...
Damage and activation of lung endothelium can lead to interstitial edema, infiltration of inflammatory cells into the interstitium and airways, and production of inflammatory metabolites, all of which propagate airway inflammation in a variety of diseases. We have previously determined that stimulation of human microvascular endothelial cells from lung (HMVEC-L) results in ...
Phospholipase A(2) (PLA(2)), a common toxic component of snake venom, has been implicated in various pharmacological effects. In this study, a basic myotoxic PLA(2), named EcTx-I was isolated from Echis carinatus snake venom by using gel filtration on Superdex G-75, and ...
Three acidic phospholipases A2 (NN-I2c-PLA2, NN-I2d-PLA2 and NN-I2c-PLA2) were purified by successive chromatography of Indian cobra (Naja naja naja) venom on CM-Sephadex C-25, Sephadex G-50 and QAE Sephadex A-25 columns. They have molecular weights of 13,000-14,500 by ...
Secretory phospholipase A(2) (sPLA(2)) expression is increased in several cancers and has been shown to trigger release from some lipid carriers. This study used electrospray ionization mass spectrometry (ESI-MS) and release of 6-carboxyfluorescein (6-CF) to determine the effects of sPLA(2) on various liposome ...
We measured phospholipase A2 activity in normal and uremic plasma, using (1-{sup 14}C)oleate-labeled autoclaved Escherichia coli as substrate. Hydrolysis of bacterial phospholipid by crude plasma from both groups was optimal at pH 5.5, was specific for the 2-acyl position of phospholipids, and had an absolute requirement for calcium. ...
In this paper was demonstrated that umbelliferone induces changes in structure and pharmacological activities of Bn IV, a lysine 49 secretory phospholipase A(2) (sPLA2) from Bothrops neuwiedi. Incubation of Bn IV with umbelliferone virtually abolished platelet aggregation, edema, and ...
In astrocytes, cytokines stimulate the release of secretory phospholipase A(2) (sPLA(2)) activity and group II(A) sPLA(2) expression. This paper reports that two sPLA(2) isoforms, group II(A) and group V, are in ...
MELTING LAYER DURING THE WAKASA BAY EXPERIMENT. Simone Tanelli", Jonathan Meagher, Stephen L. Durden ... and the associated melting layer, whose impact on ...
NASA Website
... Previously we reported that in nerve growth factor (NGF)-differentiated PC12 cells, arachidonic acid (AA) release is associated with acetylcholine ...
DTIC Science & Technology
Some myotoxic or neurotoxic PLA2s (phospholipases A2) from pit viper venoms contain characteristic N6 substitutions. Our survey of the venoms of more than ten pit viper genera revealed that N6-PLA2s exist only in limited Asian pit vipers of two genera, Protobothrops and Gloydius, and exist as either monomers or the ...
We have shown previously that interleukin-1 (IL-1) has biphasic effects on the formation of bone nodules in long-term cultures of fetal rat calvarial (RC) cells (Ellies and Aubin, Cytokine 2:430-437, 1990). To determine the role of arachidonic acid metabolism in this process, we have examined the release of prostaglandin E2 (PGE2) and phospholipase A2 ...
Cytosolic phospholipase A(2) (cPLA(2)) plays a pivotal role in mediating agonist-induced arachidonic acid (AA) release for prostaglandin (PG) synthesis during inflammation triggered by tumor necrosis factor-? (TNF-?). However, the mechanisms underlying TNF-?-induced cPLA(2) ...
Rationale Phospholipase A2, group 7 (PLA2g7), the plasma isoform of a platelet-activating factor acetylhydrolases, also known as lipoprotein associated phospholipase A2, is a circulating enzyme that catalyse hydrolysis of the sn-2 ester bond of PAF and ...
Both IFN-alpha/beta and IFN-gamma have recently been demonstrated to induce a rapid but transient activation of phospholipase A2 (PLA2) in BALB/c 3T3 fibroblasts and a human neuroblastoma cell line. We report that IFN-gamma induces the synthesis and prolonged activation of ...
The 85 kDa cytosolic phospholipase A2 (cPLA2) plays a key role in the production of arachidonic acid and lysophospholipids, the precursors of eicosanoids and platelet-activating factor. Here we report the cloning of the promoter of the human cPLA2 gene. ...
Three acidic phospholipases A2 from Indian cobra (Naja naja naja) venom inhibited platelet aggregation in platelet rich plasma induced separately by ADP, collagen and epinephrine with different potencies. The order of inhibition was epinephrine > collagen > ADP. They did not inhibit platelet aggregation induced by arachidonic acid (10 microM). The ...
The activation of phospholipase A(2) (PLA(2)) with release of eicosanoids and prostanoids in mature myeloid cells and the augmentation (priming) of this activity by cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF) are central to the inflammatory ...
Lys49 phospholipase A(2) (PLA(2) ) homologues present in crotalid snake venoms lack enzymatic activity, yet they induce skeletal muscle necrosis by a membrane permeabilizing mechanism whose details are only partially understood. The present study evaluated the effect of altering the membrane ...
In view of understanding the mechanisms of retinal neovascularization, we had reported previously that vascular endothelial growth factor (VEGF)-induced pathological retinal angiogenesis requires the activation of Src-PLD1-PKC? signaling. In the present work, we have identified cytosolic phospholipase A(2) ...
Indian cobra (Naja naja naja) venom is reported to contain multiple forms of phospholipase A2. Only a couple of them have been isolated and characterized. A lethal phospholipase A2 (NN-IVb1-PLA2) from Naja naja naja venom has been purified in three steps involving ...
Defining the mechanism for regulation of arachidonic acid (AA) release is important for understanding cellular production of AA metabolites, such as prostaglandins and leukotrienes. Here we have investigated the differential roles of protein kinase C (PKC) and mitogen-activated protein (MAP) kinase in the regulation of cytosolic phospholipase ...
BACKGROUND: Secretory phospholipase A(2) (sPLA(2)) may contribute to atherogenesis. To date, few prospective studies have examined the utility of sPLA(2) for risk stratification in coronary artery disease (CAD). METHODS: We measured plasma sPLA(2) ...
We determined the contribution of calcium-independent phospholipase A(2)? (iPLA(2)?) to lung metastasis development following breast cancer injection into wild-type (WT) and iPLA(2)?-knockout (iPLA(2)?-KO) mice. WT and iPLA(2)?-KO mice were injected in the mammary pad with ...
BackgroundLipoprotein-associated phospholipase A2 (Lp-PLA2) is thought to play modulatory roles in the development of atherosclerosis. Here we evaluated the effects of a specific lp-PLA2 inhibitor on atherosclerosis in ApoE-deficient mice and its associated ...
Flavonoids, coumarins and other polyphenolic compounds are powerful antioxidants both in hydrophilic and lipophylic environments with diverse pharmacological properties including anti-inflammatory activity. Despite being widely used as powerful therapeutic agents for blood coagulation disorders, more specifically to control some serine protease enzymes, the mechanism of ...
We recently reported that the widely distributed neuropeptide vasoactive intestinal peptide (VIP) reduces inflammatory lung injury due to a variety of agents and inhibits the associated generation of cyclo-oxygenase and lipoxygenase products. We therefore investigated whether VIP may inhibit phospholipase A2 activity, thus reducing the ...
Polyclonal antibodies to a purified neurotoxic phospholipase A2 (PLA2), VRV PL-VIIIa, from Vipera russelli venom were raised in rabbits. Anti-PL-VIIIa-Ig (gamma-globulin fraction of rabbit antiserum injected with VRV PL-VIIIa) selectively neutralized the neurotoxicity of VRV PL-VIIIa, VRV PL-V, VRV PL-VI ...
Russell's viper (Vipera russelli, also known as Daboia russelli) is one of the major causes of fatal snakebites. To date, five Daboia russelli subspecies have been recognized. Daboiatoxin (DbTx) is the main lethal phospholipase A(2) (PLA(2)) toxin in the venom of D. russelli siamensis (Myanmar viper) and has strong ...
The venom of the common Indian krait (Bungarus caeruleus) contains about a dozen isoforms of phospholipase A2 (PLA2), which exist in different oligomeric forms as well as in complexes with low-molecular-weight ligands. The basic objective of multimerization and complexation is either to inactivate ...
There is evidence that the carcinogenic and teratogenic effects attributed to the plasticizer di(2-ethylhexyl)phthalate (DEHP) are due to its major metabolite mono(2-ethylhexyl)phthalate (MEHP). MEHP is also formed ex vivo by a plasma enzyme in blood products stored in polyvinyl chloride (PVC) DEHP plastic containers. People who receive large amounts of blood products, such as hemophiliacs or ...
Severe damage to the alveolar type I epithelial cell is a characteristic morphological feature of lung injury due to numerous cases. It is postulated that excess phospholipase A2 (PLA2) activity might be responsible for these changes, as one of the naturally occurring products of this enzyme, ...
Group III phospholipase A(2) is a known mediator of inflammation, atherosclerosis and cancer in mammals. This enzyme, therefore, is a potential drug target. The availability of the human group III phospholipase A(2) (hIIIPLA(2)) amino acid sequence offers an opportunity to study its structural features by modeling. ...
This is the first crystal structure of a carbohydrate induced dimer of phospholipase A(2) (PLA(2)). This is an endogenous complex formed between two PLA(2) molecules and two mannoses. It was isolated from Krait venom (Bungarus caeruleus) and crystallized as such. The ...
Protobothrops flavoviridis (Crotalinae) venom gland phospholipase A(2) (PLA(2)) isozyme genes have evolved in an accelerated manner to acquire diverse physiological activities in their products. For elucidation of the multiplication mechanism of PLA(2) genes, a 25,026 bp genome segment ...
Alzheimer's disease (AD) is marked by an increase in the production of extracellular beta amyloid plaques and intracellular neurofibrillary tangles associated with a decline in brain function. Increases in oxidative stress are regarded as an early sign of AD pathophysiology, although the source of reactive oxygen species (ROS) and the mechanism(s) whereby beta amyloid peptides (Abeta) impact ...
Phospholipases A2 (PLA2s) are responsible for releasing the fatty acid moiety from the sn-2 position of phospholipids. These enzymes are virtually ubiquitous proteins known from all major biological taxa. Various PLA2s act in a wide array of biological processes, ...
Secreted phospholipase A2 group X overexpression in asthma and bronchial hyperresponsiveness Teal S : Secreted PLA2s in Asthma and BHR Descriptor Number : Asthma : Immunobiology (63) Word Count: 3 sPLA2 enzymes expressed in human airways and the role of these enzymes in ...
Phospholipase A2 (PLA2) neurotoxins are a family of proteins found in the venoms of crotalids, vipers and elapids. From a gross structural standpoint, PLA2 neurotoxins are quite diverse, ranging from textilotoxin with five subunits to single chain entitie...
The venom of Crotalus durissus terrificus was fractionated by reverse-phase HPLC to obtain crotapotins (F5 and F7) and PLA2 (F15, F16, and F17) of high purity. The phospholipases A2 (PLA2S) and crotapotins showed antimicrobial activity against Xanthomonas axonopodis pv. passiflorae, although ...
Although polyunsaturated fatty acids (PUFA) have been shown to stimulate neutrophil responses such as the oxygen-dependent respiratory burst (superoxide production), the mechanisms involved still remain undefined. Here we investigate the effect of PUFA on the phospholipase A2 (PLA2)-signal transduction process in ...
Ceramide has been suggested to function as a mediator of exocytosis in response to the addition of a calcium ionophore from PC12 cells. Here, we show that although cell-permeable C(6)-ceramide or a calcium ionophore alone did not increase either the degranulation of serotonin or the release of arachidonic acid (AA) from RBL-2H3 cells, their combined effect significantly stimulated these processes ...
Bacterial lipoteichoic acid (LTA) shares a structural motif with platelet-activating factor (PAF). Both molecules are strong inflammatory agents and have a glycerol backbone with two lipid chains at the sn-1 and sn-2 positions. PAF is normally inactivated by PAF-acetylhydrolase (PAF-AH), a phospholipase A2 ...
This paper reports the biochemical and pharmacological characterization of a new myotoxic PLA(2) (EC 3.1.1.4) called PhTX-I, purified from Porthidium hyoprora venom by one step analytical chromatography reverse phase HPLC. The homogeneity of the PhTX-I fraction and its molecular mass were initially evaluated by SDS-PAGE and confirmed by MALDI-TOF ...
Viperid snakes of the genus Atropoides are distributed in Mexico and Central America and, owing to their size and venom yield, are capable of provoking severe envenomings in humans. This study evaluated, using an 'antivenomics' approach, the ability of a polyspecific (polyvalent) antivenom manufactured in Costa Rica to recognize the proteins of Atropoides mexicanus and A. picadoi venoms, which are ...
A major phospholipase A2 (NN-XIII-PLA2) which constitutes 20% of the whole Naja naja naja venom was purified to homogeneity on CM-Sephadex C-25 column chromatography. NN-XIII-PLA2 is a basic protein with a mol. wt of 11,200 by SDS-PAGE. This enzyme has low enzymatic ...
In mammalian cells, cytosolic phospholipase A(2) (cPLA(2)) displays a variety of activities through the release of arachidonic acid in response to cellular stimuli. In this study, we characterize the putative cPLA(2)-like protein, AoPlaA, in the ...
Background: The mechanisms of the increased cardiac and vascular events in patients with OSA are not well understood. Arousal which is an important component of OSA was associated with increased sympathetic activation and electrocardiographic changes which prone to arrhythmias. We planned to examine the association among arousal, circulating ...
The ability of a variety of secretory phospholipases A2 (sPLA2: EC 3.1.1.4) to bind to and hydrolyse a series of phosphatidyl-alcohol substrates, in the absence of detergent, was explored by both fluorescence-based kinetic and interfacial binding assays. The enzymes used were ...