Animals ; Cardiovascular System ; chemistry ; Female ; Group II Phospholipases A2 ; blood ; Group IV Phospholipases A2 ; blood ; Group V Phospholipases A2 ; blood ; Group X Phospholipases A2 ; blood ; Male ; RNA, Messenger ; genetics ; Rats ; Rats, Wistar

BACKGROUND: Secretory phospholipase A2 (sPLA2) are a group of extracellular enzymes that release fatty acids at the sn-2 position of phospholipids. Group IIA sPLA2 (sPLA2-IIA) has been detected in the inflammatory fluids, and its plasma level increases in the inflammatory disease. This study examined the effect of sPLA2-IIA on mouse macropahges in order to investigate the potential mechanism of sPLA2-induced inflammation. MATERIALS AND METHODS: Wild type PLA2 and mutant H48Q PLA2 were purified from HEK293 cells transfected with the corresponding plasmids, and the PLA2 activities were measured using 1-palmitoyl-2-[1- (14) C]linoleoyl-3-phosphatidylethanolamine as substrates. The TNF-alpha and IL-6 released in the supernatants were determined by ELISA. In addition, the TNF-alpha and IL-6 mRNA were analyzed by RT-PCR. RESULTS: sPLA2-IIA stimulated the production of TNF-alpha and IL-6 in a dose- and time-dependent manner. In addition, the effect of sPLA2-IIA on cytokine production from the macrophage was found to be associated with the accumulation of their specific mRNA. The mRNA levels of TNF-alpha and IL-6 peaked at 2 and 6 hours in a time-dependent manner, respectively. CONCLUSION: In conclusion, the production of proinflammatory cytokine might be mediated by the binding of sPLA2-IIA to the receptors.
Animals ; Enzyme-Linked Immunosorbent Assay ; Fatty Acids ; Group II Phospholipases A2* ; HEK293 Cells ; Inflammation ; Interleukin-6* ; Macrophages ; Mice ; Phospholipases A2, Secretory ; Phospholipids ; Plasma ; Plasmids ; RNA, Messenger ; Tumor Necrosis Factor-alpha*

No abstract available.
Phosphatidylcholines* ; Phospholipases A2* ; Phospholipases*

OBJECTIVETo measure the serum level of secretory type II phospholipase A2 (sPLA2) in patients with coronary heart disease and investigate the possible relationship with IL-8 and LPA.

METHODSA total of 110 patients with acute coronary syndrome (ACS), 63 patients with stable coronary heart disease (SCHD) group and 89 non-CHD control patients were studied. Serum levels of sPLA2, IL-8, LPA and hs-CRP were measured and the correlation among these parameters was observed.

RESULTSThe levels of serum sPLA2 [(68 +/- 17) U/ml], IL-8 [(182 +/- 80) pg/ml] and LPA [(2.85 +/- 0.36) micromol/L] were significantly higher in CHD patients than those in controls [sPLA2: (55 +/- 12) U/ml; IL-8: (119 +/- 33) pg/ml; LPA: (2.34 +/- 0.36) micromol/L, all P < 0.01], and sPLA2 and IL-8 were also significantly higher in ACS patients [sPLA2: (71 +/- 18) U/ml; IL-8: (195 +/- 78) pg/ml] than those in SCHD patients [sPLA2: (63 +/- 12) U/ml; IL-8: (159 +/- 79) pg/ml, both P < 0.01]. Serum sPLA2 level was positively correlated with hs-CRP, IL-8 and LPA (r = 0.203, P = 0.007; r = 0.658, P < 0.01; r = 0.231, P = 0.005, respectively). The relative risk of having CHD is 6.248 (P < 0.01) with the sPLA2 level above 63.75 U/ml.

CONCLUSIONElevated serum sPLA2 level is a risk factor for CHD.

Adult ; Aged ; Aged, 80 and over ; C-Reactive Protein ; metabolism ; Coronary Angiography ; Coronary Disease ; blood ; diagnostic imaging ; Female ; Group II Phospholipases A2 ; Humans ; Interleukin-8 ; blood ; Lysophospholipids ; blood ; Male ; Middle Aged ; Phospholipases A ; blood ; Phospholipases A2

Human secreted phospholipase A2 GIIE (hGIIE) is involved in inflammation and lipid metabolism due to its ability of hydrolyzing phospholipids. To reveal the mechanism of substrate head-group selectivity, we analyzed the effect of mutation of hGIIE on its activity and selectivity. hGIIE structural analysis showed that E54 might be related to its substrate head-group selectivity. According to the sequence alignment, E54 was mutated to alanine, phenylalanine, and lysine. Mutated genes were cloned and expressed in Pichia pastoris X33, and the enzymes with mutations were purified with 90% purity by ion exchange and molecular size exclusion chromatography. The enzymatic activities were determined by isothermal microthermal titration method. The Km of mutant E54K towards 1,2-dihexyl phosphate glycerol decreased by 0.39-fold compared with that of wild type hGIIE (WT), and the Km of E54F towards 1,2-dihexanoyl-sn-glycero-3-phosphocholine increased by 1.93-fold than that of WT. The affinity of mutant proteins with phospholipid substrate was significantly changed, indicating that E54 plays an important role in the substrate head-group selectivity of hGIIE.
Humans ; Kinetics ; Mutation ; Phospholipases A2, Secretory ; Phospholipids ; Saccharomycetales ; Substrate Specificity

PURPOSE: In addition to cyclooxygenase-2 (COX-2) which is related to prostaglandin E2 synthesis, other enzymes such as cytosolic phospholipase A2 (cPLA2), microsomal prostaglandin E2 synthase-1 (mPGES-1), and 15-prostaglandin dehydrogenase (15-PGDH) have been suggested to be related to carcinogenesis of colorectal cancer (CRC). The aim of this study was to investigate the roles of cPLA2, COX-2, mPGES-1, and 15-PGDH in tumor progression. MATERIALS AND METHODS: cPLA2, COX-2, mPGES-1, 15-PGDH, and vascular endothelial growth factor (VEGF) expressions were immunohistochemically examined in 89 CRC, and their expressions were compared with each other or clinicopathologic parameters as well as VEGF as tumor progression parameters. RESULTS: cPLA2 was expressed in 54.5%, COX-2 in 80.5%, mPGES-1 in 96.4%, 15-PGDH in 46.1%, and VEGF in 65.9%. The expression of cPLA2 correlated with VEGF expression. COX-2 expression was correlated with the depth of invasion, tumor stage, cPLA2, and VEGF expressions. Moreover, VEGF revealed the highest expression in the tissues positive for both cPLA2 and COX-2. Furthermore, 15-PGDH expression was inversely correlated with VEGF expression. CONCLUSION: The present study demonstrates that cPLA2 and mPGES-1, in addition to COX-2, are constitutively overexpressed, and that 15-PGDH might be attenuated in colorectal cancer. Furthermore, cPLA2 and 15-PGDH as well as COX-2 could have an important role in tumor progression.
Aged ; Colorectal Neoplasms/*enzymology ; Cyclooxygenase 2/*metabolism ; Female ; *Gene Expression Regulation, Enzymologic ; Group IV Phospholipases A2/*metabolism ; Humans ; Hydroxyprostaglandin Dehydrogenases/*metabolism ; Immunohistochemistry ; Intramolecular Oxidoreductases/metabolism ; Male ; Middle Aged

Infantile neuroaxonal dystrophy (INAD) is a rare neurodegenerative disease. Two boys aged 3 years and 4 years and 2 months respectively, were admitted to the hospital due to delayed mental and motor development. There were no abnormalities at birth, and both children had low muscle strength and tension on admission. One child was not able to stand alone and had impaired vision. Electromyography showed neurogenic damage, and head MRI revealed cerebellar atrophy. High-throughput sequencing revealed compound heterozygous mutations in the PLA2G6 gene in the two children. The mutations (IVS11-1G>T and c.1984C>G) in one child were new mutations, and immunohistochemistry showed a reduction in the protein expression of PLAG6 in the muscular tissue of this child. INAD has the main clinical manifestations of psychomotor developmental regression and cerebellar atrophy. High-throughput sequencing can help with clinical diagnosis.
Child, Preschool ; Group VI Phospholipases A2 ; genetics ; Humans ; Magnetic Resonance Imaging ; Male ; Mutation ; Neuroaxonal Dystrophies ; genetics ; Neurodegenerative Diseases ; genetics

OBJECTIVETo investigate the therapeutic mechanism of rhubarb in protecting the intestinal muco-membranous barrier in the mice.

METHODBal b/c mice were divided into 2 groups, gavaged with normal saline and 10% rhubarb decoction, respectively. The animals were killed after 24 hours after the treatments. The intestinal juice was collected after intestinal lavage and centrifuged for determination of IgA, total protein, C3, high density lipoprotein, type II PLA2 activity, and content of lysozyme. At the same time, 40 mg of small intestine were incised in each mouse. Reverse transcription polymerase chain reaction (RT-PCR) and gel image analysis were performed to detect the content of the cryptdin gene expression.

RESULTThe content of IgA, total protein, the C3, lysozyme, and the type II PLA2 activity in intestinal lavaged juice exhibited the statistical differences between the two groups (P < 0.05). There were no significant difference in the ontents of HDL, cryptdin-1 and cryptdin-4 gene expression between the two groups (P > 0.05).

CONCLUSIONRhubarb could increase secretion of several immune associated substances of the mucous membrane in normal intestine, indicating a possibility to abate the injury of intestine mucus resulted from severe stress induced by trauma, burn and shock. Through above mechanisms Rhubarb may also reduce the incidence of bacterial translocation and systemic inflammatory reaction syndrome (SIRS).

Animals ; Complement C3 ; metabolism ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Group II Phospholipases A2 ; Immunoglobulin A ; metabolism ; Intestinal Mucosa ; metabolism ; Intestinal Secretions ; metabolism ; Intestine, Small ; metabolism ; Mice ; Mice, Inbred BALB C ; Muramidase ; metabolism ; Phospholipases A ; metabolism ; Phospholipases A2 ; Plants, Medicinal ; chemistry ; Proteins ; metabolism ; Rheum ; chemistry

Acute Lung Injury ; metabolism ; Animals ; Extremities ; blood supply ; Group II Phospholipases A2 ; metabolism ; Male ; Rats ; Rats, Wistar ; Reperfusion Injury ; metabolism ; Taurine ; pharmacology

OBJECTIVETo investigate the effects of simvastatin on lipopolysaccharides (LPS) induced upregulation of Lp-PLA(2) in human peripheral blood monocytes-macrophages and the related mechanisms.

METHODSPeripheral blood monocytes of healthy volunteer were isolated and incubated for 2-3 days. Monocytes were incubated with various concentrations of LPS for 6 h or with 1 µg/ml of LPS for different times in LPS group. In simvastatin group and MAPK inhibitors groups, cells were pre-treated with simvastatin (10(-2) - 10(-7) mmol/L) or various MAPK inhibitors (10 µmol/L SB203580, 20 µmol/L U0126, and 20 µmol/L SP600125) before LPS co-incubation. Lp-PLA(2) activity was measured by chronometry, Lp-PLA(2) mRNA expression was detected by RT-PCR. Protein expressions of Lp-PLA(2) and p38MAPK and phosphorylated p38MAPK were examined by Western blot.

RESULTS(1) LPS significantly upregulated Lp-PLA(2) mRNA and protein expression, as well as the enzyme activity in a time and concentration dependent manner, which could be significantly attenuated by simvastatin in a time and concentration dependent manner. (2) Simvastatin significantly reduced LPS-induced p38MAPK phosphorylation. The p38 MAPK inhibitor SB203580, but not MEK1/2 inhibitor U0126 and JNK inhibitor SP600125, completely prevented LPS-mediated up-regulation of Lp-PLA(2) at protein level.

CONCLUSIONThis study demonstrated that LPS significantly upregulated Lp-PLA(2) mRNA and protein expression, as well as the enzyme activity in a time and concentration dependent manner via Rho-p38MAPK pathway, which could be significantly suppressed by simvastatin.

1-Alkyl-2-acetylglycerophosphocholine Esterase ; Anthracenes ; pharmacology ; Butadienes ; pharmacology ; Cells, Cultured ; Humans ; Imidazoles ; pharmacology ; Lipopolysaccharides ; pharmacology ; Macrophages ; drug effects ; metabolism ; Monocytes ; drug effects ; metabolism ; Nitriles ; pharmacology ; Phospholipases A2 ; metabolism ; Phosphorylation ; Pyridines ; pharmacology ; RNA, Messenger ; genetics ; Simvastatin ; pharmacology ; p38 Mitogen-Activated Protein Kinases ; metabolism