OBJECTIVETo determine the concentrations of interleukin-18 (IL-18), IL-6, IL-8, and prostaglandin E2 (PGE2) in the synovial fluid in patients with osteoarthritis (OA), and explore the role of IL-18 in the pathogenesis of OA.

METHODSThe synovial fluid was collected from 30 patients with knee OA, and the concentrations of IL-18 and the other cytokines were measured using enzyme-linked immunosorbent assay (ELISA). A linear regression was performed between IL-18 and the other cytokines.

RESULTSThe average IL-18 and PGE2 concentrations were 220-/+304 pg/ml and 89-/+104 pg/ml in the synovial fluid, respectively, and the two cytokines showed a positive correlation in the synovial fluid (r=0.628, P=0.001). The IL-18 concentration was also correlated to the concentrations of IL-6 (1200-/+1587 pg/ml, n=22; r=0.590, P=0.008) and IL-8 (5190-/+6024 pg/ml, n=9; r=0.776, P=0.014).

CONCLUSIONIL-18 can promote PGE2 production, which causes cartilage degradation in OA, thus therapies targeting this cytokine may prove an effective approach to early OA treatment.

Aged ; Dinoprostone ; biosynthesis ; Female ; Humans ; Interleukin-18 ; metabolism ; Male ; Middle Aged ; Osteoarthritis ; metabolism ; Synovial Fluid ; metabolism

OBJECTIVE: To detect cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) release in human nasal epithelia (HNE) induced by lipopolysaccharide (LPS) in different concentration gradient and time gradient, and to investigate their roles in nasal inflammatory pathogenesis. METHOD: Western Blot and fluorescent real time quantitative PCR were performed to detect the expression of COX-2 in HNE induced by LPS and blocked by selective inhibitor of COX-2. The concentrations of PGE2 were determined by enzyme immunoassay. RESULT: Low expressions of COX-2 and PGE2 were detected in normal HNE. COX-2 expression and PGE2 release increased in HNE induced by LPS in time-dependent or dose-dependent manner. The increased release of PGE2 was later than that of COX-2 expression. COX-2 expression and PGE2 release were dose-dependently attenuated by selective inhibitor of COX-2. CONCLUSION LPS effectively induces COX-2 expression and PGE2 release in HNE. And COX-2 is responsible for the synthesis of PGE2. These results indicate that the increased expression of COX-2 and PGE2 is involved in the inflammation of HNE induced by LPS in vitro.
Cells, Cultured ; metabolism ; Cyclooxygenase 2 ; metabolism ; Dinoprostone ; biosynthesis ; metabolism ; Epithelial Cells ; metabolism ; Humans ; Lipopolysaccharides ; Nasal Mucosa ; cytology ; metabolism

OBJECTIVETo study the effects of sinomenine (Sin) on cell proliferation, intracellular expression of cyclooxygenase-2 (COX-2), and production of PGE2 in lipopolysaccharide-induced PC-12 cells, To explore the Sin's mechanism on nerve cell.

METHODPC-12 cells were cultured with nerve growing factors (NGF), and pretreated with Sin at various concentrations (0, 3 x 10(-6), 30 x 10(-6), 150 x 10(-6) mol x L(-1)) for 2 hours, then with or without stimulation of lipopolysaccharide (LPS). The proliferation activity of PC-12 cells was determined by 3H-TdR incorporation, and the production of PGE2 in culture supernatants of PC-12 cells was detected with competitive ELISA. Expression of COX-2 mRNA in PC-12 cells was analyzed by semi-quantitative RT-PCR, and expression of COX-2 protein was estimated by Western blot method and cellular enzyme immunoassay. Nuclear factor-kappa B (NF-kappaB) activity in whole-cell extract of PC-12 cells was also measured by an ELISA-based method.

RESULTThe data showed that Sin down-regulated the expression of COX-2 mRNA and protein, and reduced the production of PGE2 in the LPS-stimulated PC-12 cells which correlated with Sin's concentrations positively. In addition, NF-kappaB activity in LPS-stimulated cells was suppressed significantly by Sin. No inhibition of proliferation of PC-12 cells due to Sin treatment was observed.

CONCLUSIONSin mediates the down-regulation of expression of COX-2 and production of induced PGE2 in PC-12 cells by suppressing the activity of NF-kappaB.

Animals ; Cell Proliferation ; drug effects ; Cyclooxygenase 2 ; Dinoprostone ; biosynthesis ; Down-Regulation ; Lipopolysaccharides ; Morphinans ; isolation & purification ; pharmacology ; NF-kappa B ; metabolism ; PC12 Cells ; Plants, Medicinal ; chemistry ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Sinomenium ; chemistry

OBJECTIVETo observe in vitro the effect of Sinomenine, a pure alkaloid extracted from the chinese medical plant Sinomenium acutum on the activity of cyclooxygenase (COX-1 and COX-2) and the expression of COX-1 and COX-2 mRNA.

METHODMononuclear leukocytes were obtained from healthy adults. Isolated mononuclear leucocytes from human peripheral blood (PBMC) were incubated (1 x 10(6).mL-1) with or without sinomenine (or indomethacin), after incubated for 24 hours at 37 degrees C with 5% CO2; the media were assayed for the PGE2 by radioimmunoassay (RIA). LPS was used to stimulate the monocytes at a concentration of 5 micrograms.mL-1. And by RT-PCR, both COX-1 and COX-2 mRNAs were detected in Mononuclear leukocytes after incubation for different hours with drug (sinomenine or indomethacin) or not.

RESULTLPS (stimulated) induced the production of PGE2 in PBMC increasing with high expression of COX-2 mRNA; sinomenine reduced PGE2 production in LPS stimulated human monocytes more than in non-stimulated human monocytes. In comparative experiments, indomethacin, a non selective COX inhibitor, reduced the production of PGE2 equally in both states. Meanwhile, neither sinomenine(0.1-1 mmol.L-1) nor indomethacin(0.5-10 mumol.L-1) inhibited the expression of both COX-1 and COX-2 mRNAs by RT-PCR with beta-actin as reference.

CONCLUSIONIn contrast with indomethacin, Sinomenine shows a preferential inhibitory effect on COX-2 over COX-1, These results suggest that Sinomenine is a selective COX-2 inhibitor, which may be directly related to suppressing cyclooxygenase activity.

Adult ; Cyclooxygenase 1 ; Cyclooxygenase 2 ; Dinoprostone ; blood ; Humans ; Isoenzymes ; biosynthesis ; Leukocytes, Mononuclear ; enzymology ; Membrane Proteins ; Morphinans ; isolation & purification ; pharmacology ; Plants, Medicinal ; chemistry ; Prostaglandin-Endoperoxide Synthases ; biosynthesis ; metabolism ; RNA, Messenger ; biosynthesis ; Sinomenium ; chemistry

OBJECTIVETo investigate the effect of lipopolysaccharide of Porphyromonas gingivalis (Pg-LPS) on the bio-thythetic pathway of prostaglandin E2 (PGE2) and its difference from lipopolysaccharide of Escherichia coli (Ec-LPS).

METHODSPurified Pg-LPS and Ec-LPS were used to stimulate a human monocytic cell strain THP-1. PGE2 concentration was determined by an enzyme immunoassay kit. The release of tritium labeled arachidonic acid (AA) was detected by a liquid scintillation counter. Reverse transcription polymerase chain reaction and western blot were used to analyse the expression of cytosolic phospholipase A2 (cPLA2) enzyme, cyclooxygenase-2 (COX-2), and microsomal prostaglandin E synthase-1 (mPGES-1).

RESULTSThe effect of Pg-LPS on induction of PGE2 and release of AA was significantly weaker than that of Ec-LPS (P < 0.05).Increased secretion of PGE2 was observed after stimulation with Pg-LPS for 6 h, which peak at 24 h at (221.40 +/- 29.46) ng/L; or with Ec-LPS for 1-48 h, at (161.80 +/- 17.31) approximately (379.80 +/- 37.35) ng/L. The highest levels of COX-2 and mPGES-1 were shown after 16 h treatment by Pg-LPS, or after 8 h and 16 h by Ec-LPS respectively.cPLA2 inhibitor AACOCF3 could lower the level of LPS-induced release of AA, while it did not influence the production of PGE2. COX-2 inhibitor NS-398 could remarkably reduce the concentration of PGE2.

CONCLUSIONSPg-LPS showed delayed and weaker effect on PGE2 biosynthetic pathway than Ec-LPS. Pg-LPS-induced PGE2 synthesis was mainly due to enhanced expression of COX-2 and mPGES-1, whereas cPLA2 played an insignificant role.

Cell Line ; Cyclooxygenase 2 ; metabolism ; Dinoprostone ; biosynthesis ; Humans ; Intramolecular Oxidoreductases ; metabolism ; Lipopolysaccharides ; pharmacology ; Monocytes ; drug effects ; metabolism ; Porphyromonas gingivalis ; Prostaglandin-E Synthases

OBJECTIVEThe purpose of this study was to investigate the effects of epidermal growth factors (EGFs) with different concentration on the OD, DNA, protein, and PGE2 of A/J mouse embryonic palatal shelves cells (A/J MEPC) isolated from embryonic palatal shelves.

METHODSThe mouse embryonic palatal shelves cells were grown in different 39 pores (or bottles) with 9 gradient concentrations of EGF (0.005, 0.010, 0.050, 0.100, 0.500, 1.000, 5.000, 10.000, 50.000 ng/ml), and four pores were prepared for the same concentration, then the OD, DNA, protein and PGE2 of A/J MEPC were measured after 1 day, 3 days and 5 days.

RESULTSEGFs stimulated DNA and PGE2 synthesis of A/J MEPC, and augmented proliferation index (PIX). Their effects were very obvious in promoting the proliferation of A/J MEPC, when the concentration was 10.000 ng/ml.

CONCLUSIONEGF may be important in regulating proliferation and metabolism of embryonic palatal shelves cells.

Animals ; Cell Division ; drug effects ; Cells, Cultured ; DNA ; analysis ; Dinoprostone ; biosynthesis ; Dose-Response Relationship, Drug ; Embryo, Mammalian ; Epidermal Growth Factor ; pharmacology ; Mice ; Palate ; cytology

OBJECTIVEThis study was to explore the cytotoxic effect and the related injury mechanism of deoxynivalenol (DON) on articular chondrocytes in human embryo.

METHODSArticular cartilage cells were isolated from knees of human embryo and cultured in DMEM/F12 medium. The cells of the 4th generation were divided into five groups and incubated with varying concentrations of DON as the followings: control group and group with DON of 0.1, 0.2, 0.4, 1.0 µg/ml. The effects of DON were observed 72 hours after incubation. Cell apoptosis was assayed by flow cytometry (FCM) with Annexin V-FITC/PI staining; MMP-13 and PGE2 were detected by ELISA kits; NO was measured by Griess assay with spectrophotometer. Inducible nitric oxide synthase (iNOS) and collagen II in cells were detected by FCM. The expression levels of iNOS, mRNA and collagen II mRNA were measured with RT-PCR.

RESULTSThe rates of cell apoptosis in DON groups were 6.78% - 19.05%, which were significantly higher than that in control (1.20%, F = 174.761, P < 0.05). The levels of NO in DON groups were 20.8 - 40.7 µmol/L, which were significantly higher than that in control (10.2 µmol/L, F = 91.966, P < 0.05). The levels of MMP-13 in DON groups were 0.25 - 0.56 µmol/L, which were significantly higher than that in control (0 µmol/L, F = 78.420, P < 0.05). The levels of PGE2 in DON groups were 3.2-20.6 µmol/L, which were significantly higher than that in control (11.6 µmol/L, F = 276.453, P < 0.05). The proportions of cells with positive iNOS in DON groups were 14.8% - 56.8% which were significantly higher than that in controls (7.1%, F = 214.614, P < 0.05). The proportions of cells with positive collagen II in groups with DON of 0.4 µg/ml and 1.0 µg/ml were 56.7% and 52.7%, which were significantly lower than that in control (62.2%, F = 5.134, P < 0.05). The relative absorbance values of iNOS mRNA in DON groups were 1.07 - 1.33, which were significantly higher than that in control (0.62, F = 8.358, P < 0.05). The levels of collagen II mRNA in groups with DON of 0.4 µg/ml and 1.0 µg/ml were 0.83 and 0.82, which were significantly lower than that in control (1.14, F = 7.887, P < 0.05).

CONCLUSIONDON could promote anabolism of NO in articular cartilage cells by which up-regulated the expression of PGE2 and MMP-13, which both promoted resolution of articular cartilage matrix such as collagen II. DON induced apoptosis in articular cartilage cells.

Cartilage, Articular ; cytology ; embryology ; Cells, Cultured ; Chondrocytes ; drug effects ; metabolism ; Dinoprostone ; metabolism ; Humans ; Matrix Metalloproteinase 13 ; metabolism ; Nitric Oxide ; biosynthesis ; Trichothecenes ; toxicity

Effect of antiatherogenic high density lipoprotein (HDL) and apolipoprotein AI (apoAI) on production of prostaglandin E2 (PGE2) by human monocyte-derived macrophages was investigated. Macrophages were loaded with acetylated low density lipoprotein followed by incubation with HDL3 or apoAI. PGE2 produced and secreted in culture supernatant was quantified by enzyme immunoassay. HDL3 induced production of PGE2 by macrophages in a time-dependent manner. 24 h after incubation, PGE2 production by HDL3-treated macrophages increased 3.7-fold of that by control cells. ApoAI also induced PGE2 secretion to 2.1-fold, which was significantly less than HDL3. The data indicate that both HDL3 and lipid-free apoAI enhance PGE2 synthesis and secretion by human macrophages and this may further contribute to the protection from atherosclerosis.
Apolipoprotein A-I ; pharmacology ; Arteriosclerosis ; prevention & control ; Culture Media, Conditioned ; Dinoprostone ; biosynthesis ; Humans ; Lipoproteins, HDL ; pharmacology ; Lipoproteins, HDL3 ; Macrophages ; cytology ; metabolism ; Monocytes ; metabolism

Prostaglandin E2(PGE2) has been implicated as an immunosuppressive agent and plasma levels of PGE2 are elevated in patients sustaining thermal injury. We examined the effect of 10(-7) M prostaglandin E2(PGE2) on human polymorphonuclear leukocytes (PMN) to determine whether it directly inhibits stimulated responses of these cells. At this concentration, PGE2 alone was incapable of stimulating PMN intracellular hydrogen peroxide production (indirectly assayed by fluorescence of 2',7'ichlorofluorescin) or expression of the PMN CD11b/CD16 surface glycoproteins. PMN incubated in the presence of the soluble stimul phorbol myristate acetate(PMA, 100 ng/ml) or recombinant human C5a(rHC5a, 10(-8) M) generated significant amounts of hydrogen peroxide, increased their CD11b expression and decreased their CD16 expression. Pre-incubation of cells with PGE2 caused significant inhibition of all the observed changes stimulated by rHC5a. In contrast, events stimulated by PMA were not affected by preincubation of cells with PGE2. We conclude that PGE2, in concentrations identical to those found in the plasma of patients with burn injuries, is capable of selectively inhibiting some stimulated events and phenotypic expression of PMN in vitro study.
Dinoprostone/*pharmacology ; Dose-Response Relationship, Drug ; Human ; Hydrogen Peroxide/metabolism ; Immunosuppressive Agents/*pharmacology ; Macrophage-1 Antigen/biosynthesis ; Neutrophils/*drug effects/immunology ; Receptors, IgG/biosynthesis ; Support, Non-U.S. Gov't ; Temperature ; Tetradecanoylphorbol Acetate/pharmacology ; Time Factors

Cyclooxygenase (COX) is a key enzyme in the conversion of arachidonic acid into prostanoids which participate in various cellular functions including apoptosis, mitogenesis, inflammation, immune modulation and differentiation. Moreover, the synthetic glucocorticoid, dexamethasone has immune modulating and anti-inflammatory effects in vivo. Recently, dexamethasone was found to enhance retinoic acid-induced neuronal differentiation. In this study, we investigated the mechanisms of dexamethasone-mediated neuronal differentiation. Immunoblotting and morphological analysis demonstrated that dexamethasone induced neuronal differentiation through COX 1 induction. This phenomenon was inhibited by indomethacin, a COX inhibitor. In addition, the addition of exogenous prostaglandin E2 (PGE2), a substance produced by the COX-mediated pathway, triggered neurite outgrowth of cells treated with COX inhibitor. Taken together, COX 1 appears to play an important role in dexamethasone-mediated neuronal differentiation.
Animals ; Anti-Inflammatory Agents/pharmacology ; Cell Differentiation/*drug effects ; Cyclooxygenase Inhibitors/pharmacology ; Dexamethasone/*pharmacology ; Dinoprostone/metabolism ; Enzyme Induction ; Hybrid Cells ; Indomethacin/pharmacology ; Isoenzymes/*biosynthesis ; Mice ; Prostaglandin-Endoperoxide Synthase/*biosynthesis ; Rats ; Tumor Cells, Cultured