A UPLC-MS/MS method based on metabonomic skills was developed to study the serum metabolic changes of rats after acute liver injury induced by CCl4 and to evaluate the action mechanism of Si-Ni-San. The integrated data were exported for principal components analysis (PCA) by using SIMCA-P software, in order to find the potential biomarkers. It showed that clear separation of healthy control group, model group, silymarin group, Si-Ni-San group was achieved by using the PCA method. Nine significantly changed metabolites were identified as potential biomarkers of acute liver injury. Compared with the health control group, the model group rats showed higher levels of phenylalanine, tryptophan and GCDCA together with lower levels of LPC 16 : 0, LPC 18 : 0, LPC 18 : 1, LPC 16 : 1, LPC 20 : 4 and LPC 22 : 6. These changes of serum metabolites suggested that the disorders of amino acid metabolism, lipid metabolism, bile acid biosynthesis and anti-oxidative damage were related to acute liver injury induced by CCl4. Si-Ni-San might have the anti-liver injury effect on all these four metabolic pathways.
Animals ; Carbon Tetrachloride Poisoning ; Chemical and Drug Induced Liver Injury ; blood ; etiology ; Chromatography, High Pressure Liquid ; methods ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Glycodeoxycholic Acid ; blood ; Lysophosphatidylcholines ; blood ; Male ; Metabolomics ; Phenylalanine ; blood ; Plants, Medicinal ; chemistry ; Principal Component Analysis ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tandem Mass Spectrometry ; Tryptophan ; blood

OBJECTIVETo examine the effects of niacin on lysophosphatidylcholine (LPC)-induced intercellular adhesion molecule-1 (ICAM-1), and gained insight to the mechanisms.

METHODHuman umbilical vein endothelial cell line was cultured using Medium 200 medium in incubator at 37 °C and 5% CO2 condition.Experimental groups:(1) the negative control group:medium; (2) LPC different time groups:the medium added with 20 µmol/L final concentration of LPC, were cultured for 10 min and 8 h, 24 h; (3) LPC+ p38-mitogen-activated protein kinase (p38MAPK) inhibitor (SB203580) group:the medium added with 10 µmol/L p38MAPK inhibitor (SB203580) was cultured for 1 h, then human umbilical vein endothelial cells (HUVECs) added with the LPC were cultured for 10 min, 8 h and 24 h.(4) LPC+different niacin dose group:after separately adding with 0.25, 0.5, 1 mmol/L niacin, the cells were cultured for 18 h, then HUVECs added with the LPC were cultured for 10 min, 8 h and 24 h. Cell concentration in each group was 5×10(5)/ml, inoculated in 6-well plates, each well 1 ml. Detected by Western blot analysis of pp38MAPK, ICAM-1 protein content, real-time quantitative PCR to detect endothelial cell ICAM-1 mRNA expression, cell immunofluorescence to detect LPC-induced ICAM-1 protein expression.

RESULTIn LPC 24 h group, the expression of ICAM-1 protein was significantly increased 0.786 ± 0.02, the LPC+niacin group, ICAM-1 protein levels (0.487 ± 0.015) was significantly lower than the LPC 24 h group (P < 0.01), in LPC+SB203580 intervention group, ICAM-1 protein levels (0.461 ± 0.011) was significantly lower than that of the LPC 24 h group (P < 0.01), but did not reach the level of the control group. Adding LPC to culture for 10 min, phosphorylation of p38MAPK (pp38MAPK) reached its peak (0.47 ± 0.02), niacin could reduce the pp38MAPK (0.07 ± 0.02), SB203580 could also reduce its activity (0.11 ± 0.02). Adding LPC to culture for 8 h, ICAM-1 mRNA expression (8.16 ± 0.15) compared with the control group (1.00 ± 0.02) had a significant increase (t = 24.34, P < 0.01). Compared with the LPC 8 h, niacin reduced LPC-induced ICAM-1 mRNA expression (3.85 ± 0.14), and showed a dose-dependent manner (F = 8.06, P < 0.01), while SB203580 could not effectively reduce the ICAM-1 mRNA (8.09 ± 0.11).

CONCLUSIONNiacin prevented LPC-induced endothelial dysfunction by reducing expression of ICAM-1. These mechanisms appeared to be at least partly mediated by suppression of the pp38MAPK in endothelial cells. These pleiotropic effects of niacin may potentially contribute to the beneficial effects of risk reduction for atherosclerotic disease.

Atherosclerosis ; metabolism ; prevention & control ; Cell Adhesion ; drug effects ; Cells, Cultured ; Enzyme Inhibitors ; administration & dosage ; pharmacology ; Gene Expression Regulation ; drug effects ; Human Umbilical Vein Endothelial Cells ; drug effects ; metabolism ; Humans ; Imidazoles ; administration & dosage ; pharmacology ; Intercellular Adhesion Molecule-1 ; genetics ; metabolism ; Lysophosphatidylcholines ; administration & dosage ; pharmacology ; Niacin ; administration & dosage ; pharmacology ; Pyridines ; administration & dosage ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Real-Time Polymerase Chain Reaction ; Signal Transduction ; p38 Mitogen-Activated Protein Kinases ; antagonists & inhibitors ; metabolism

The balance between tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAI-1) regulates fibrinolysis. PAI-1 expression increases in atherosclerotic arteries and vascular smooth muscle cells (VSMCs) are one of major constituents of atheroma. We investigated the impact of lysophosphatidylcholine (lysoPC), an active component of oxidized low-density lipoprotein, on the plasminogen activator system of the rat VSMCs. The lysoPC stimulated the protein and gene expressions of PAI-1 but did not affect the protein expression of t-PA. Fibrin overlay zymography revealed that lysoPC increased the activity of PAI-1 in the conditioned media, while concurrently decreasing that of free t-PA. Vitamin E inhibited the lysoPC-induced PAI-1 expression. Further, lysoPC increased the intracellular reactive oxygen species (ROS) formation. Caffeic acid phenethyl ester, an inhibitor of NF-kappaB, blocked this lysoPC effect. Indeed, lysoPC induced the NF-kappaB-mediated transcriptional activity as measured by luciferase reporter assay. In addition, genistein, an inhibitor of protein-tyrosine kinase (PTK), diminished the lysoPC effect, while 7,12-dimethylbenz[a]anthracene, a stimulator of PTK, stimulated PAI-1 production. In conclusion, lysoPC does not affect t-PA expression but induces PAI-1 expression in the VSMC by mediating NF-kappaB and the genistein-sensitive PTK signaling pathways via oxidative stress. Importantly, lysoPC stimulates the enzyme activity of PAI-1 and suppresses that of t-PA.
Animals ; Benz(a)Anthracenes/pharmacology ; Caffeic Acids/pharmacology ; Cells, Cultured ; Genistein/pharmacology ; Lipoproteins, LDL/metabolism ; Lysophosphatidylcholines/*pharmacology ; Muscle, Smooth, Vascular/cytology/*drug effects/metabolism ; NF-kappa B/antagonists & inhibitors/metabolism ; Oxidative Stress/drug effects ; Phenylethyl Alcohol/analogs & derivatives/pharmacology ; Plasminogen Activator Inhibitor 1/agonists/genetics/*metabolism ; Protein Kinase Inhibitors/pharmacology ; Protein-Tyrosine Kinases/antagonists & inhibitors/metabolism ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species/metabolism ; Signal Transduction/drug effects ; Tissue Plasminogen Activator/*metabolism ; Transcription, Genetic/drug effects ; Up-Regulation/drug effects ; Vitamin E/pharmacology

OBJECTIVETo investigate the effect of fluvastatin on lysophosphatidylcholine (LPC)-induced ventricular arrhythmias and its mechanism.

METHODSTwenty male SD rats were randomly allocated into two equal groups, namely LPC treatment group and fluvastatin pretreatment group. Langendorff apparatus was used for cardiac perfusion ex vivo with 5 µmol/L LPC for 5 min followed by washing for 30 min in LPC treatment group, and in fluvastatin pretreatment group, a 30-min perfusion with 10 µmol/L fluvastatin was administered before LPC perfusion. The LPC-induced nonselective cation current (I(NSC)) in the ventricular myocytes was recorded using the whole-cell voltage-clamp method.

RESULTSFluvastatin significantly inhibited LPC-induced ventricular tachyarrhythmia/fibrillation and I(NSC). The small G-protein Rho inhibitor (C3) and Rho-kinase inhibitor (Y-27632) in the pipette solution also suppressed LPC-induced I(NSC).

CONCLUSIONFluvastatin offers cardiac protection against LPC by inhibiting LPC-induced I(NSC). LPC induces fatal arrhythmia via a Rho/Rho-kinase-mediated pathway.

Animals ; Arrhythmias, Cardiac ; chemically induced ; metabolism ; Drug Antagonism ; Fatty Acids, Monounsaturated ; pharmacology ; Indoles ; pharmacology ; Ion Channels ; drug effects ; Lysophosphatidylcholines ; adverse effects ; Male ; Myocytes, Cardiac ; metabolism ; Rats ; Rats, Sprague-Dawley ; rho-Associated Kinases ; metabolism

This study was to report the effect of Tangshen Formula on phospholipids metabolism in diabetic nephropathy patients. A normal phase-HPLC-TOF/MS method was used in this study for the determination of seven species of phospholipids in human plasma. Then, the concentration changes of potential phospholipids biomarkers were discussed in diabetic nephropathy phase III and phase IV patients among different groups, including before and 3, 6 months after administration of Tangshen Formula. Significant increases of PE750, PI885, PC792, PC826, PC830, PC854 and PC802 levels were observed 6 months after administration of Tangshen Formula and conventional western medicine, as well as a decrease of LPC540 level, when compared with those before medication. Concentrations of all the potential phospholipids biomarkers showed a tendency towards normal levels; however, both the improvement degree and onset time of these compounds were not same. Additionally, Tangshen Formula treatment based on conventional western medicine treatment was more efficient in adjusting the levels of these compounds when compared with western medicine treatment alone, especially for the phase IV patients. These results indicated that Tangshen Formula was capable in regulating and improving phospholipids metabolism in diabetic nephropathy patients, which may be related with the direct or indirect inhibition of protein kinase C pathway and the corresponding reduction of phospholipase A2 activity. Therefore, Tangshen Formula may be used as an effective drug for diabetic nephropathy therapy, at least as an adjunctive therapeutic drug.
Diabetic Nephropathies ; blood ; metabolism ; Double-Blind Method ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Glycerophospholipids ; blood ; Humans ; Lysophosphatidylcholines ; blood ; Phospholipases A2 ; metabolism ; Phospholipids ; blood ; classification ; Plants, Medicinal ; chemistry ; Protein Kinase C ; metabolism ; Signal Transduction ; Sphingomyelins ; blood

OBJECTIVETo investigate the potential preventive effects of metformin on non-alcoholic fatty liver disease (NAFLD) and roles of phospholipase A2/lysophosphatidylcholine pathway in hepatocyte lipoapoptosis in a rat NAFLD model induced by high-fat diet.

METHODMale SD rats (n = 36) were randomly divided into three groups with 12 rats in each and treated with different diet and drugs: group I: ordinary diet, group II: high-fat diet, group III: high-fat diet and metformin. Ten weeks later, the rats were sacrificed and their body weight and liver weight were obtained, serum lipid metabolic indexes, insulin resistance indexes and secretory phospholipase A2 (sPLA2), lysophosphatidylcholine (LPC) levels and other parameters were measured. Phospholipase A2 mRNA expression levels were measured by quantitative reverse transcription-polymerase chain reaction (RT-PCR). In addition, the histological changes of liver tissue were analyzed.

RESULTCompared to ordinary diet group, the rat's liver weight (g) (16.92 ± 2.49 vs. 12.16 ± 0.82), hepatic exponent (0.034 ± 0.004 vs. 0.026 ± 0.002), serum alanine aminotransferase (U/L) (45.43 ± 9.73 vs. 29.42 ± 6.73), triglyceride (mmol/L) (1.22 ± 0.24 vs. 0.85 ± 0.19), cholesterol (mmol/L) (2.00 ± 0.37 vs. 1.49 ± 0.33), lipoprotein(a) (mmol/L) (743.86 ± 32.19 vs. 648.42 ± 78.87), low-density lipoprotein (mmol/L) (1.31 ± 0.35 vs. 0.65 ± 0.22), insulin (mmol/L) (22.16 ± 5.16 vs. 16.86 ± 5.35), insulin resistance index(5.10 ± 1.45 vs. 3.59 ± 0.99), free fatty acid (mEq/L) (0.57 ± 0.10 vs. 0.35 ± 0.07), sPLA2 [µmol/(min·ml)] (0.130 ± 0.016 vs. 0.098 ± 0.024), lysophosphatidylcholine (µmol/L) (707.26 ± 92.48 vs. 508.87 ± 96.50), leptin (pg/ml (80.08 ± 17.73 vs. 65.11 ± 14.09), liver triglyceride (mg/g) (13.57 ± 0.65 vs. 12.03 ± 1.14), cholesterol (mg/g) (2.19 ± 0.15 vs. 1.94 ± 0.12) (P < 0.05) were significantly increased in high-fat diet group. Moreover, degree of hepatic steatosis was significantly higher and sPLA2 mRNA expression was also significantly increased. Secondly, in comparison with high-fat diet group, early metformin treatment significantly reduced the rat's body weight (g) (394.40 ± 33.10 vs. 491.86 ± 26.45), liver weight (g) (13.24 ± 1.16 vs. 16.92 ± 2.49), serum alanine aminotransferase (U/L) (30.40 ± 4.50 vs. 45.43 ± 9.73), triglyceride (mmol/L) (0.75 ± 0.19 vs. 1.22 ± 0.24), cholesterol (mmol/L) (1.61 ± 0.38 vs. 2.00 ± 0.37), insulin (mmol/L) (16.96 ± 5.60 vs. 22.16 ± 5.16), insulin resistance index (3.75 ± 1.41 vs. 5.10 ± 1.45), sPLA2 [µmol/(min·ml)] (0.101 ± 0.009 vs. 0.130 ± 0.016), lysophosphatidylcholine (µmol/L) (549.92 ± 90.78 vs. 707.26 ± 92.48), liver triglyceride (mg/g) (11.23 ± 1.70 vs. 13.57 ± 0.65), cholesterol (mg/g) (1.97 ± 0.20 vs. 2.19 ± 0.15) (P < 0.05). Moreover, degree of hepatic steatosis was significantly lower and sPLA2 mRNA expression was also significantly decreased by metformin. Thirdly, when compared to ordinary diet group, metformin could also significantly increase hepatic exponent (0.034 ± 0.004 vs. 0.026 ± 0.002) and low-density lipoprotein level (mmol/L) (0.96 ± 0.34 vs. 0.65 ± 0.22) (P < 0.05). However, it had no impact on hepatic steatosis and sPLA2 expression (P > 0.05).

CONCLUSIONIt was indicated that metformin has potent effects on improving lipid metabolism and insulin resistance in high-fat diet induced non-alcoholic fatty liver disease rat model. The liver protective mechanisms of metformin in non-alcoholic fatty liver disease may be contributed to down-regulation of secretory phospholipase A2 mRNA expression, decrease in serum secretory phospholipase A2, lysophosphatidylcholine, lower inflammatory response and protect mitochondrial function.

Animals ; Apoptosis ; Disease Models, Animal ; Down-Regulation ; Fatty Liver ; drug therapy ; enzymology ; pathology ; Insulin Resistance ; Lipid Metabolism ; Lysophosphatidylcholines ; metabolism ; Male ; Metformin ; pharmacology ; Non-alcoholic Fatty Liver Disease ; Phospholipases A2 ; metabolism ; Rats ; Rats, Sprague-Dawley ; Signal Transduction

OBJECTIVETo discuss the effect of protein kinase C (PKC) on regulation of ecto-5'-nucleotidase activity by lysophosphatidylcholine(LPC) in human umbilical endothelial cells (HUVEC).

METHODSExperiments were conducted in HUVEC grown on dishes which were divided into 4 groups (n=15): (1) Control group in which only eAMP (5 micromol/L) was added; (2) LPC group in which HUVEC were incubated with LPC (10 micromol/L) before eAMP was added; (3) Chelerythrine group in which cells were pre-incubated with the PKC inhibitor chelerythrine (100 micromol/L) before LPC and eAMP were added; (4) alpha, beta-Methyladenosine-5'-Diphosphate (AOPCP) group in which cells were incubated with AOPCP (10 micromol/L) before eAMP was added. Etheno-adenosine production was detected at 15th, 30th, 45th min with high performance liquid chromatography(HPLC) respectively.

RESULTSComparing to the control group LPC significantly increased etheno-adenosine production at three time points respectively (P < 0.05). Furthermore, PKC inhibitor chelerythrine abolished this effect of LPC and the ethenoadenosine production at three time points were at the same level of control group (P > 0.05). CD73 inhibitor AOPCP significantly decreased the etheno-adenosine production compared to the other three groups (P < 0.01).

CONCLUSIONEcto-5'-nucleotidase can be modulated within minutes following exposure of HUVEC to LPC and this response may be mediated by PKC in HUVEC.

5'-Nucleotidase ; metabolism ; Cells, Cultured ; GPI-Linked Proteins ; metabolism ; Human Umbilical Vein Endothelial Cells ; cytology ; metabolism ; Humans ; Lysophosphatidylcholines ; pharmacology ; Protein Kinase C ; physiology ; Up-Regulation ; drug effects

OBJECTIVETo investigate the protective effect of neferine against damages of endothelial cells induced by lysophos-phatidylcholine (LPC) and the relationship with asymmetric dimethylarginine (ADMA).

METHODThe human umbilical vein endothelial cells (HUVEC-12) were treated with LPC (10 mg x L(-1)) for 24 h to establish the model of endothelial cells damages; HUVECs were prior exposed to neferine (0.1, 1.0 or 10.0 micromol x L(-1) ) for 1 h, and then exposed to LPC in the presence of the neferine for 24 h. At the end of the experiment, the cultured medium was collected for measuring the concentration of nitric oxide (NO), aleic dialdehyde (MDA) as well as ADMA and the cells were collected for measuring the level of intracellular reactive oxygen species (ROS).

RESULTCompared with control group, exposure of endothelial cells to LPC (10 mg x L(-1)) for 24 h significantly increased the concentration of MDA and ADMA in the medium and the level of intracellular ROS and coinstantaneously significantly decreased the concentration of NO in the medium. Neferine (0.1, 1.0 or 10.0 micromol x L(-1)) significantly inhibited the elevated concentration of MDA, ADMA as well as the level of intracellular ROS and coinstantaneously significantly attenuated the decreased level of NO induced by LPC.

CONCLUSIONNeferine can protect the endothelial cells against damages induced by LPC and the protective effect is related to the decrease of the concentration of ADMA.

Arginine ; analogs & derivatives ; metabolism ; Benzylisoquinolines ; pharmacology ; Cell Line ; Endothelial Cells ; drug effects ; metabolism ; Humans ; Lysophosphatidylcholines ; pharmacology ; Malondialdehyde ; metabolism ; Nitric Oxide ; metabolism ; Reactive Oxygen Species ; metabolism

Lysophosphatidylcholine (LPC) is a bioactive lipid generated by phospholipase A2-mediated hydrolysis of phosphatidylcholine. In the present study, we demonstrate that LPC stimulates phospholipase D2 (PLD2) activity in rat pheochromocytoma PC12 cells. Serum deprivation induced cell death of PC12 cells, as demonstrated by decreased viability, DNA fragmentation, and increased sub-G1 fraction of cell cycle. LPC treatment protected PC12 cells partially from the cell death and induced neurite outgrowth of the cells. Overexpression of PLD2 drastically enhanced the LPC-induced inhibition of apoptosis and neuritogenesis. Pretreatment of the cells with 1-butanol, a PLD inhibitor, completely abrogated the LPC-induced inhibition of apoptosis and neurite outgrowth in PC12 cells overexpressing PLD2. These results indicate that LPC possesses the neurotrophic effects, such as anti-apoptosis and neurite outgrowth, through activation of PLD2.
Starvation ; Rats ; Phospholipase D/antagonists & inhibitors/*metabolism ; PC12 Cells ; Neurites/*drug effects ; Lysophosphatidylcholines/*pharmacology ; Cell Survival/drug effects ; Apoptosis/*drug effects ; Animals

OBJECTIVE: To investigate the effects of fenofibrate on the proliferation and apoptosis and endothelial nitric oxide synthase (eNOS) mRNA expression of cultured human umbilical vein endothelial cells (HUVECs) induced by lysophosphatidylcholine (LPC). METHODS: HUVECs were cultured in vitro. The study was designated to 5 groups according to fenofibrate concentration: control group, LPC group, LPC + low-concentration fenofibrate (10 micromol/L), LPC + middle-concentration fenofibrate (50 micromol/L), and LPC + high-concentration fenofibrate (100 micromol/L). The study was designated to 6 groups according to the intervention time: control group, LPC group, LPC + fenofibrate (50 micromol/L) 6 h, LPC + fenofibrate 12 h, LPC + fenofibrate 24 h, and LPC + fenofibrate 48 h. The proliferation and apoptosis of HUVECs were evaluated by MTT assay, flow cytometry and fluorescence microscopy, respectively. eNOS mRNA were assayed by real time-PCR. RESULTS: Compared with the control group, LPC could inhibit the proliferation and induce apoptosis, and downregulate eNOS mRNA expression and decrease NO production of HUVECs. Fenofibrate could increase the proliferation and decrease the apoptosis, and up-regulate eNOS mRNA expression and enhance NO production in HUVECs. CONCLUSION Fenofibrate could improve the proliferation and inhibit the apoptosis, and up-regulate eNOS mRNA expression of HUVECs induced by LPC, which may be responsible for fenofibrate to prevent and treat atherosclerosis.
Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Endothelium, Vascular ; cytology ; Fenofibrate ; pharmacology ; Humans ; Hypolipidemic Agents ; pharmacology ; Lysophosphatidylcholines ; pharmacology ; Nitric Oxide Synthase Type III ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Umbilical Veins ; cytology