AIMTo investigate the effect of different peroxisome proliferator-activated receptors (PPARs) activators on plasminogen activator inhibitor-1 in HepG-2 cell line and explore the effect of PPARs on PAL-1 gene expression.

METHODSStearic acid, oleic acid, linoleic acid, fenofibrate, pioglitazone were used in the treatment of HepG-2 cell culture. The level of PAI-1 and PPARs mRNA was measured by reverse transcription-polymerase chain reaction (RT-PCR) and the level of PAI-1 activity and PPARs protein was determined by colorimetric assay and western blotting respectively.

RESULTSThe mRNA and activity of PAI-1 significantly increased in the groups of oleic acid and linoleic acid compared with the control, but decreased in the group of fenofibrate. There were no significant changes in both groups of stearic acid and pioglitazone. The alterations in the level of PPARs mRNA and protein were not detected in all the treated groups compared with the control.

CONCLUSIONPeroxisome proliferator-activated receptors activators play important roles in the PAI-1 gene expression and regulation. It is likely mediated by the activation of PPARalpha, but there might be other mechanisms.

Fenofibrate ; pharmacology ; Hep G2 Cells ; Humans ; Linoleic Acid ; pharmacology ; Oleic Acid ; pharmacology ; Peroxisome Proliferator-Activated Receptors ; agonists ; metabolism ; Plasminogen Activator Inhibitor 1 ; genetics ; metabolism ; RNA, Messenger ; genetics

OBJECTIVETo investigate the effects of peroxisome proliferator activated receptor-alpha (PPAR-a) activation on oleic acid (OA)-induced steatosis and hepatic expression of heme oxygenase-1 (HO-1) using an in vitro cell model system.

METHODSA steatosis human hepatocyte in vitro model system was established by treating HepG2 cells with 0.2 mmol/L of oleic acid for 24 hours. The steatosis cells were then divided into four groups for an additional 24 hours of treatment with 0.2 mmol/L of oleic acid alone (model control group) or with 5, 10 or 50 pnol/L of fenofibrate (FF, a selective PPAR-a agonist; experimental groups). Untreated HepG2 cells served as non-steatosis controls. Effect of PPAR-a activation on fat accumulation was detected by Oil Red O staining and on intracellular triglyceride (TG) levels by enzymatic assay. mRNA and protein expression of PPAR-alpha and HO-1 were quantified by real-time PCR and immunocytochemistry, respectively. One-way ANOVA and the LSD t-test were used for between-group comparisons, and correlation analysis was performed with the Pearson's correlation coefficient.

RESULTSThe steatosis model control cells showed significantly increased TG deposition (379.98 +/- 23.19 mg/g protein, vs. non-steatosis controls F = 148.56, P< 0.01), significantly decreased mRNA and protein expression of PPAR-alpha (0.42 +/- 0.38,F= 177.64,P< 0.01 and 0.47 +/- 0.14, F= 120.76,P< 0.01) and HO-1 (0.36 +/- 0.66, F= 74.77,P< 0.01 and 0.26 +/- 0.10,F= 119.90,P<0.01). FF (5, 10 and 50 micromol/L) inhibited the steatosis induced by OA in a concentration-dependent manner (294.00 +/- 19.80, 250.33 +/- 9.96, and 196.99 +/- 9.14, F = 148.56, P <0.01) and increased the mRNA and protein expression of PPAR-alpha (0.55 +/- 0.65, 0.85 +/- 0.61, and 1.31 +/- 0.36,F= 177.64,P< 0.01; 0.82 + 0.11, 1.31 +/- 0.16, and 1.75 +/- 0.13, F= 120.76,P <0.01) and HO-1 (0.62 +/- 0.05, 0.84 +/- 0.07, and 1.30 +/- 0.11,F= 74.77,P <0.01; 0.44 +/- 0.08, 0.81 +/- 0.08, 1.20 +/- 0.10,F= 119.90,P< 0.01).

CONCLUSIONActivation of PPAR-a prevents OA-induced steatosis in HepG2 cells, and HO-1 may function as a downstream effector of this mechanism.

Fatty Liver ; chemically induced ; Heme Oxygenase-1 ; metabolism ; Hep G2 Cells ; Humans ; Oleic Acid ; pharmacology ; PPAR alpha ; metabolism ; Triglycerides ; metabolism

OBJECTIVETo investigate the effect of oleic acid on the proliferation and secretion of pro-inflammatory mediators of human normal fibroblasts and scar fibroblasts.

METHODSHuman normal fibroblasts and scar fibroblasts were cultured in vitro and respectively divided into seven groups according to the random number table, with 8 samples in each group. Cells in blank control (BC) group were routinely cultured without addition of other agents. Cells in ethanol-control (EC) group were cultured with medium with the addition of 2% absolute ethanol. Cells in oleic acid groups were cultured with the addition of oleic acid in concentration of 0.25, 0.50, 1.00, 2.00, or 4.00 mmol/L in 2% absolute ethanol. The growth of cells in each group was observed with trypan blue staining on post culture day (PCD) 1-5. On PCD 2, structure of cells in BC, EC, and 1.00 mmol/L oleic acid groups was observed under inverted phase contrast microscope and transmission electron microscope; cell cycle of BC, EC, and 1.00 mmol/L oleic acid groups was measured by flow cytometer; cell proliferation activity in each group was measured by MTT assay; the level of NO in supernatant was assayed by Griess assay; the levels of TNF-α, IL-1β, IL-6, and IL-8 in supernatants in each group were determined by enzyme-linked immunosorbent assay. Data were processed with multifactor and repeated measurement design analysis of variance.

RESULTS(1) There was no significant difference in each index of normal fibroblasts and scar fibroblasts between BC group and EC group. (2) The numbers of normal fibroblasts and scar fibroblasts in 2.00 and 4.00 mmol/L oleic acid groups were significantly lower than those in corresponding BC and EC groups on PCD 2-5 (with F values respectively 13.773 and 11.344, P values all below 0.01). (3) On PCD 2, the numbers of normal fibroblasts and scar fibroblasts in 1.00 mmol/L oleic acid groups decreased, and the cells were aggregating, rounding, and easy to drop off. Cellular membrane disruption, vacuolar degeneration of mitochondrion, pyknosis, and lipid droplets were observed. (4) The percentages of G0/G1 and G2/M phases of normal fibroblasts in 1.00 mmol/L oleic acid group [(93.56 ± 9.98)%, (2.01 ± 0.75)%] were significantly higher than those in BC group [(84.23 ± 10.96)%, (0.37 ± 0.16)%, with F values respectively 3.026, 34.751, P < 0.05 or P < 0.01], while the percentage of normal fibroblasts in S phase [(4.42 ± 0.87)%] was markedly lower than that in BC group [(16.06 ± 1.74)%, F = 136.120, P < 0.01]. The percentages of scar fibroblasts of G0/G1 and G2/M phases in 1.00 mmol/L oleic acid group [(93.86 ± 13.90)%, (1.89 ± 0.66)%] were significantly higher than those in BC group [(83.88 ± 10.42)%, (0.41 ± 0.17)%, with F values respectively 3.529, 32.710, P < 0.05 or P < 0.01], and the percentage of scar fibroblasts in S phase [(3.87 ± 0.63)%] was markedly lower than that in BC group [(15.89 ± 2.02)%, F = 116.508, P < 0.01]. (5) The proliferation rates of normal fibroblasts and scar fibroblasts in 0.50-4.00 mmol/L oleic acid groups were significantly lower than those in corresponding BC and EC groups (with F values respectively 215.945 and 194.555, P < 0.05 or P < 0.01). (6) The content of NO in supernatant of normal fibroblasts in all oleic acid groups was obviously higher than that in BC and EC groups (F = 30.240, P < 0.05 or P < 0.01). The contents of NO in supernatants of scar fibroblasts in 1.00-4.00 mmol/L oleic acid groups were significantly higher than that in BC and EC groups (F = 12.495, P < 0.01). The contents of TNF-α and IL-6 in supernatants of normal fibroblasts and scar fibroblasts in 2.00 and 4.00 mmol/L oleic acid groups were obviously higher than those in corresponding BC and EC groups (with F(TNF-α) values respectively 6.911, 3.818, F(IL-6) values respectively 16.939, 11.600,P < 0.05 or P < 0.01). The contents of IL-1β in supernatants of normal fibroblasts and scar fibroblasts in groups of every concentration of oleic acid were significantly higher than those in corresponding BC and EC groups (with F values respectively 25.117, 9.137, P values all below 0.01). The contents of IL-8 in supernatants of normal fibroblasts in 1.00-4.00 mmol/L oleic acid groups were markedly higher than those in BC and EC groups (F = 2.717, P < 0.05 or P < 0.01). The contents of IL-8 in supernatants of scar fibroblasts in 2.00 and 4.00 mmol/L oleic acid groups were significantly higher than those in BC and EC groups (F = 3.338, P < 0.05). There was no statistically significant difference in above indexes between normal fibroblasts and scar fibroblasts in the same concentration of oleic acid group (with F values from 0.120 to 3.766, P values all above 0.05).

CONCLUSIONSAlthough oleic acid in high concentration inhibits the proliferation of scar fibroblasts, it also inhibits the proliferation of normal fibroblasts. Oleic acid in high concentration can cause excessive and continued inflammatory reaction by promoting the secretion of pro-inflammatory mediators of normal fibroblasts and scar fibroblasts, and they are detrimental to wound healing.

Cell Proliferation ; drug effects ; Cells, Cultured ; Cicatrix ; metabolism ; Fibroblasts ; cytology ; drug effects ; secretion ; Humans ; Inflammation Mediators ; metabolism ; Oleic Acid ; pharmacology

OBJECTIVETo establish an in vitro cell model to investigate hepatic steatosis of non-alcoholic fatty liver disease.

METHODSHepG2 cells cultured in MEM containing 10 % fetal bovine serum were divided into control group and model group. At 7 0%-80 % confluency, HepG2 cells in model group were exposed to a long-chain mixture of free fatty acids (oleate and palmitate) for 24 h, cells in control group were subject to fresh medium. Lipid droplets were observed with oil red O stain and electron microscope, triglyceride and malonaldehyde were detected by respective assay kits.

RESULTA large number of lipid droplet were detected in model HepG2 cells; the level of triglyceride increased. However,malonaldehyde did not increase significantly compared with control group.

CONCLUSIONA large number of lipid droplet were detected in model HepG2 cells; the level of triglyceride increased. However, malonaldehyde did not increase significantly compared with control group.

Culture Media ; pharmacology ; Fatty Acids, Nonesterified ; pharmacology ; Fatty Liver ; Hep G2 Cells ; Humans ; Models, Biological ; Non-alcoholic Fatty Liver Disease ; Oleic Acid ; pharmacology ; Palmitates ; pharmacology

OBJECTIVEImpaired active fluid transport of alveolar epithelium may involve in the pathogenesis and resolution of alveolar edema. The objective of this study was to explore the changes in alveolar epithelial liquid clearance during lung edema following acute lung injury induced by oleic acid.

METHODSForty-eight Wistar rats were randomly divided into six groups, i.e., injured, amiloride, ouabain, amiloride plus ouabain and terbutaline groups. Twenty-four hours after the induction of acute lung injury by intravenous oleic acid (0.25 ml/kg), 5% albumin solution with 1.5 microCi (125)I-labeled albumin (5 ml/kg) was delivered into both lungs via trachea. Alveolar liquid clearance (ALC), extravascular lung water (EVLW) content and arterial blood gases were measured one hour thereafter.

RESULTSAt 24 h after the infusion of oleic acid, the rats developed pulmonary edema and severe hypoxemia, with EVLW increased by 47.9% and ALC decreased by 49.2%. Addition of either 2x10(-3) M amiloride or 5x10(-4) M ouabain to the instillation further reduced ALC and increased EVLW. ALC increased by approximately 63.7% and EVLW decreased by 46.9% with improved hypoxemia in the Terbutaline (10(-4) M) group, compared those in injured rats. A significant negative correlation was found between the increment of EVLW and the reduction of ALC.

CONCLUSIONSActive fluid transport of alveolar epithelium might play a role in the pathogenesis of lung edema in acute lung injury.

Adrenergic beta-Agonists ; pharmacology ; Animals ; Epithelium ; metabolism ; Oleic Acid ; adverse effects ; Pulmonary Alveoli ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Respiratory Distress Syndrome, Adult ; chemically induced ; metabolism ; Terbutaline ; pharmacology

To examine the role of glycogen synthase kinase 3 (GSK-3) in the apoptosis of pancreatic beta-cells to better understand the pathogenesis and to find new approach to the treatment of type 2 diabetes, apoptosis was induced by oleic acid (OA) in INS-1 cells and the activity of GSK-3 was inhibited by LiCl. The PI staining and flow cytometry were employed for the evaluation of apoptosis. The phosphorylation level of GSK-3 was detected by Western blotting. The results showed that OA at 0.4 mmol/L could cause conspicuous apoptosis of INS-1 cells and the activity of GSK-3 was significantly increased. After the treatment with 24 mmol/L of LiCl, a inhibitor of GSK-3, the OA-induced apoptosis of INS-1 cells was lessened and the phosphorylation of GSK-3 was increased remarkably. It is concluded that GSK-3 activation plays an important role in OA-induced apoptosis in pancreatic beta-cells and inhibition of the GSK-3 activity can effectively protect INS-1 cells from the OA-induced apoptosis. Our study provides a new experimental basis and target for the clinical treatment of type-2 diabetes.
Apoptosis/*drug effects ; Cell Line ; Fatty Acids, Nonesterified/*pharmacology ; Glycogen Synthase Kinase 3/*metabolism ; Insulin-Secreting Cells/*cytology ; Oleic Acid/pharmacology ; Phosphorylation

BACKGROUNDAnimal models that demonstrate changes of renal function in response to acute lung injury (ALI) and mechanical ventilation (MV) are few. The present study was performed to examine the effect of ALI induced by oleic acid (OA) in combination with conventional MV strategy on renal function in piglets.

METHODSTwelve Chinese mini-piglets were randomly divided into two groups: the OA group (n = 6), animals were ventilated with a conventional MV strategy of 12 ml/kg and suffered an ALI induced by administration of OA, and the control group (n = 6), animals were ventilated with a protective MV strategy of 6 ml/kg and received the same amount of sterile saline.

RESULTSSix hours after OA injection a severe lung injury and a mild-moderate degree of renal histopathological injury were seen, while no apparent histological abnormalities were observed in the control group. Although we observed an increase in the plasma concentrations of creatinine and urea after ALI, there was no significant difference compared with the control group. Plasma concentrations of neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C increased (5.6 ± 1.3) and (7.4 ± 1.5) times in the OA group compared to baseline values, and were significantly higher than the values in the control group. OA injection in combination with conventional MV strategy resulted in a dramatic aggravation of hemodynamic and blood gas exchange parameters, while these parameters remained stable during the experiment in the control group. The plasma expression of TNF-α and IL-6 in the OA group were significantly higher than that in the control group. Compared with high expression in the lung and renal tissue in the OA group, TNF-α and IL-6 were too low to be detected in the lung and renal tissue in the control group.

CONCLUSIONSOA injection in combination with conventional MV strategy not only resulted in a severe lung injury but also an apparent renal injury. The potential mechanisms involved a cytokine response of TNF-α and IL-6 in plasma, lung and renal tissues.

Acute Lung Injury ; chemically induced ; pathology ; physiopathology ; Animals ; Cytokines ; analysis ; Hemodynamics ; Kidney ; pathology ; physiopathology ; Lung ; pathology ; Oleic Acid ; pharmacology ; Respiration, Artificial ; Swine ; Swine, Miniature

OBJECTIVE: To explore the effect of ulinastain on the expression of hemeoxy genase-1 (HO-1) in oil acid-induced acute lung injury in rats. METHODS: The animal model of acute lung injury was established by oil acid. Thirty SD rats were randomly divided into 3 groups: the blank control group (A), the acute lung injury group (B) and the acute lung injury group (C) followed by injecting 100 mL/kg ulinastatin. Each group consisted of 10 rats. Group A were given 0.2 mL/kg natural solution through the trial vein; Group B and C were given 0.2 mL/kg oil-acid through trial vein, while group C were injected 100mL/kg ulinastatin by the peritoneal cavity after injecting oil acid. After 4 hours, the rates of respiration were counted and blood samples were cramped out through the heart puncture for blood gas analysis. The expressions of hemeoxygenase-1 and the pathologic construction changes were determined by HE staining in the lower right lung of rats in the 3 groups. RESULTS: The respiration dysfunction caused by oil acid could be prominently improved by ulinastain. There was only a little expression of hemeoxygenase-1 in the lung of Group A, but the expression increased in Group B and significatively increased in Group C. CONCLUSION Ulinastatin may protect the rats from acute lung injury through increasing the expression of HO-1.
Acute Lung Injury ; chemically induced ; metabolism ; Animals ; Glycoproteins ; pharmacology ; Heme Oxygenase (Decyclizing) ; metabolism ; Lung ; drug effects ; metabolism ; Male ; Oleic Acid ; adverse effects ; Rats ; Rats, Sprague-Dawley

AIMTo test the enhancing activity and the mechanism of oleyl pyroglutamate used as transdermal enhancer.

METHODSThe penetration-enhancing effects of oleyl pyroglutamate, oleyl alcohol and oleic acid on the three drugs (caffeine, tinidazole and cortisone) were observed; the transdermal enhancing mechanism of oleyl pyroglutamate was studied with the attenuated total reflectance Fourier-transfer infrared spectroscopy(ATR-FTIR) of the human stratum corneum in vivo.

RESULTSThe penetration-enhancing ratio of the three drugs was 7.9 fold, 41.8 fold and 2.8 fold, respectively. The absorptions at 2,800-2,950 cm-1 and 1,642-1,646 cm-1 (amide-I) in the ATR-FTIR spectrum of the stratum were found to be shifted differently following removal of the stratum corneum which was treated with oleyl pyroglutamate.

CONCLUSIONOleyl pyroglutamate showed better penetration-enhancing effect on the penetration of drugs. Its transdermal enhancing mechanism may be that oleyl pyroglutamate induced not only disordering of the stratum corneum lipid, but also change of the secondary structure of keratin.

Administration, Cutaneous ; Adult ; Animals ; Caffeine ; administration & dosage ; pharmacokinetics ; Cortisone ; administration & dosage ; pharmacokinetics ; Fatty Alcohols ; pharmacology ; Humans ; Male ; Mice ; Oleic Acid ; pharmacology ; Pyrrolidonecarboxylic Acid ; analogs & derivatives ; chemistry ; pharmacology ; Skin Absorption ; drug effects ; Tinidazole ; administration & dosage ; pharmacokinetics

OBJECTIVETo investigate the relationship of lung stress index and positive end-expiratory pressure (PEEP) at post-recruitment in different canine acute respiratory distress syndrome (ARDS) models.

METHODSThe ARDS models were induced by intravenous oleic acid, saline lavage and hydrochloric acid aspiration in anesthetized dogs. During volume control ventilation with constant inspiratory flow, PEEP was set to obtain a b (stress index) value between 0.9 and 1.1 (b = 1) before and post recruitment maneuver (RM). PEEP was changed to obtain b < 1 (0.6 < b < 0.8) and b > 1 (1.1 < b < 1.3). Meanwhile, the recruited volume (RV) was measured and pulmonary mechanics and gas exchange were observed.

RESULTSAt b = 1 after RM, PEEP were (10.8 +/- 2.3), (12.8 +/- 1.8) and (9.2 +/- 1.8) cm H2O in the oleic acid, saline-lavaged and hydrochloric acid aspiration groups, respectively. PEEP in saline-lavaged group was higher than that in hydrochloric acid aspiration group (P < 0.05). The ratio of partial arterial oxygen tension and fraction of inspiratory oxygen (PaO(2)/FiO(2)) at b = 1 without RM was lower than those post-RM in all three groups (P < 0.05). In oleic acid group, PaO(2)/FiO(2) at b = 1 post-RM was (399 +/- 61) mm Hg, which was higher than that at b < 1 [(307 +/- 71) mm Hg], but there was no difference between those at b = 1 and b > 1. At b = 1 after RM, PaO(2)/FiO(2) in the saline-lavaged group was higher than that in acid aspiration group, but no difference between saline-lavaged group and oleic acid group was found. At b = 1 post-RM, RV were higher than that at b = 1 before RM in all three groups (P < 0.01), but there was no significant difference among three groups. At b = 1 post-RM in three groups, pulmonary compliance were higher than those at b > 1, but airway plateau pressure were lower than those at b > 1.

CONCLUSIONSLung stress index could be a good indicator for PEEP titration at post-RM.

Animals ; Disease Models, Animal ; Dogs ; Female ; Hydrochloric Acid ; pharmacology ; Lung ; physiopathology ; Lung Compliance ; Male ; Oleic Acid ; pharmacology ; Positive-Pressure Respiration ; Respiratory Distress Syndrome, Adult ; chemically induced ; physiopathology ; therapy ; Respiratory Function Tests ; Sodium Chloride ; pharmacology