Effect of caveolin-1 expression on high-salt diet-induced endothelial dysfunction in type 1 diabetic rats

AIM: To investigate the underlying mechanisms responsible for endothelial dysfunction of type 1 diabetes mellitus (DM) rats fed with high-salt diet. METHODS: Type 1 DM was induced by intraperitoneal injection of streptozotocin (70 mg/kg). Normal and diabetic rats were fed high-salt food (HS, 8% NaCl) and standard food for 6 weeks, respectively. Isometric tension of the mesenteric arteries were measured. The expression of Akt, endothelial nitric oxide synthase (eNOS) and caveolin-1 (Cav-1) was examined by Western blot. RESULTS: The rats in DM+HS group exhibited more pronounced impairment of vasorelaxation to acetylcholine and insulin compared with either DM group or HS group (P<0.01). Akt and eNOS phosphorylation levels, and nitric oxide (NO) concentration in DM+HS group were significantly lower than those in DM group (P<0.01). The level of Cav-1 in DM+HS group was significantly higher than that in DM group and HS group. CONCLUSION: Impaired endothelial Akt activation, increased Cav-1 expression and resultant decreased eNOS activation contribute to aggravate high-salt diet-induced endothelial dysfunction and hypertension in DM rats.     

Effect of Sini decoction on GST expression in the ischemic myocardium

AIM:To detect the effect of Sini decoction on glutathione S-transferase (GST) mRNA expression in the ischemic myocardium. METHODS:Kunming mice were randomly divided into control group, ischemic group and Sini decoction group. Total RNA was extracted from the myocardium of mice in each group. The effect of Sini decoction on the expression of GST gene was detected by RT-PCR. RESULTS:The expression of GST mRNA in Sini decoction group was significantly up-regulated compared with the ischemic group and control group.CONCLUSION:Sini decoction can promote the expression of GST gene,which may be related to its protective effect on ischemic myocardium.     

Liver protection by Sini decoction in hemorrhagic shock and its mechanism relating to oxygen free radical and nitric oxide

AIM:The work was designed to explore protective effects of a traditional Chinese medicine-sini decoction (SD) on liver in hemorrhagic shock and its mechanism relating to oxygen free radical and nitric oxide.METHODS:Anesthetized Wistar rats were subjected to a hemorrhagic shock protocol for 60 min followed by intravenous injection with normal sodium chloride solution or SD solution. Superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO) in liver were examined. The inducible nitric oxide synthase (iNOS) was determined immunohistochemically. RT-polymerase chain reaction (RT-PCR)was used to assay the mRNA, which were corresponding to eNOS (endothelial nitric oxide synthase) and iNOS.RESULTS:The activity of SOD decreased, while the concentration of MDA increased in liver during hemorrhagic shock. SD enhanced SOD activity and inhibited a increase in MDA level in liver (P＜0.01). The NO concentrations in liver in SD group increased at three hours after resuscitation (P<0.01). In addition, it was found that the expression of iNOS was upregulated in sodium chloride-treated group, while SD upregulated the expression of eNOS.CONCLUSION:SD reduces the liver injury caused by oxygen free radicals during hemorrhagic shock. The increasing NO concentration by SD is through upregulation of endothelial NOS expression.     

Effects of Sini decoction on the ultrastructure of small intestinal epithelial cells in rats with intestinal ischemia-reperfusion

AIM: To investigate the effect of Sini decoction (SND)on the ultrastructure of small intestinal epithelial cells in rats with intestinal ischemia-reperfusion. METHODS: Thirty-two Sprague-Dawley rats of both sexes were randomly divided into 4 groups: (1) Control group in which sham operation was performed; (2) Model group in which intestinal I/R was produced by clamping super mesenteric artery(SMA) for 1 hour and declamping SMA for 3 hours; (3) SND1 group in which SD (0.6 g/200 g rat) was given via stomach tube 3 d before intestinal I/R; (4) SND2 group in which SD (1.2 g/200 g rat)was given via stomach tube 3 d before intestinal I/R. A strip of small intestine was taken from distal end of ileum for electron microscopic examination. The two-dimensional structural parameters and three-dimensional structural parameters of mitochondria were calculated. RESULTS: (1)Morphological changes of small intestine: In control group, epithelial cells were orderly arranged, with normal mitochondria and intestinal villi. In model group, the gaps between epithelial cells widened. There were a lot of apoptotic cells. Microvilli were short and swelled. Mitochondria were swelled obviously with broken ridges. Endoplasmatic reticulum was severely dilated. In SND1 and SND2 groups, microvilli and epithelial cells were orderly arranged relatively, mitochondria was slightly swelled. (2) Structural parameters of mitochondria: In model group, there were the least mitochondria and the swelling of mitochondria was severe. In SND1 and SND2 groups, the mitochondria was more than that of model group and the swelling were slight. CONCLUSION: Sini decoction can protect small intestine from ischemia-reperfusion injury without dose-dependent effect.     

Effects of Sini decoction on atherosclerosis and ceramide content of aorta in rabbits

AIM:To observe the effects of Sini decoction on atherosclerosis(AS) and ceramide content of aorta in rabbits. METHODS:28 rabbits were randomly divided into three groups. Control group was fed with a normal diet; High cholesterol group was fed 1% cholesterol and 5% fat diet; Sini decotion+ high cholesterol group was fed 1% cholesterol and 5% fat diet plus Sini decotion (4.2 g·kg^-1·d^-1). At the end of study, the plaque area were measured, the atorta ceramide and cell apoptosis were also detected. RESULTS:Sini decotion diminished lipid plaque area on the aortic endothelium, reduced the levels of aorta ceramide and the apoptosis index. CONCLUSION:Sini decoction has an inhibitory effect on AS, the mechanism may be that Sini decotion reduces concentration of ceramide in aorta.     

Effects of Sini decoction against pulmonary injury induced by ex vivo ischemia-reperfusion in rats

AIM: To observe the effects of Sini decoction against pulmonary injury induced by ex vivo ischemia-reperfusion in rats. METHODS: The model of ischemia-reperfusion was established. Twenty-four Sprague-Dawley rats were randomly divided into Sham, I/R, and SND groups. Wet to dry lung weight ratio (W/D), mean pulmonary artery pressure (MPAP), SOD activity and MDA contents in pulmonary perfusate and tissue, NOS activity and NO contents in pulmonary tissue were detected. The pathologic changes in pulmonary tissue were also observed by light microscope. RESULTS: The morphological changes of pulmonary injury were alleviated in SND group. Wet/dry ratio, MPAP and MDA contents in pulmonary perfusate and tissue were significantly lower in SND group after ischemic/reperfusion. SOD activity in pulmonary perfusate and tissue, and NO contents in pulmonary tissue were significantly higher in SND group than those in I/R group. No significant difference in NOS activity in pulmonary tissue among three groups was observed. CONCLUSION: These results indicate that SND may have a protective effect on ischemia-reperfusion injured lung by its antioxidant activity and by adjusting NO level.     

Naringin protects human umbilical vein endothelial cells against injury induced by high glucose through PI3K/AKT/eNOS pathway

AIM: To investigate the protective effect of naringin (Nar) on the injury of human umbilical vein endothelial cells (HUVECs) induced by 33 mmol/L high glucose (HG) and to explore its possible mechanisms.METHODS: The injury model was established by treating HUVECs with HG medium for the indicated time (6, 12, 24, 48 and 72 h), and then the levels of NO, eNOS and p-eNOS were detected, respectively. The effects of Nar on high glucose-induced endothelial cell injury were observed. HUVECs were treated with Nar at concentrations of 5, 10, 25, 50 and 100 mg/L for 6 h, 12 h, 24 h, 36 h and 48 h. The levels of NO in the supernatants were measured. The effects of Nar on HG-injured HUVECs were explored by treating the cells with 10 μmol/L of LY294002, a PI3K inhibitor, or 0.5 μmol/L of AKT inhibitor Ⅳ, an AKT inhibitor, and then the levels of NO, PI3K, AKT, eNOS and their phosphorylated proteins were determined by Western blot.RESULTS: Nar at concentration of 50 mg/L significantly attenuated the injury of endothelial cells induced by high glucose (P<0.01), and the protective effects of Nar were abolished by pretreating with the inhibitor of PI3K or AKT (P<0.01).CONCLUSION: Nar protects endothelial cells against the injury induced by high glucose through PI3K/AKT/eNOS pathway.     

Role of sphingosine 1-phosphate on high glucose-induced vascular endothelial cell dysfunction

AIM: To explore the role of sphingosine 1-phosphate (S1P) in the dysfunction of vascular endothelial cells exposed to high glucose. METHODS: In human aortic endothelial cells cultured under high-glucose (22 mmol/L glucose) medium, nitric oxide (NO) level, polymorphonuclear neutrophil-endothelial cell adhesion rate, protein level of intercellular adhesion molecule-1 (ICAM-1), migration of endothelial cells and Akt/endothelial nitric oxide synthase (eNOS) pathway activation were observed after S1P, sphingosine kinase-1 inhibitor and/or Akt inhibitor treatments. RESULTS: S1P decreased NO level, increased polymorphonuclear neutrophil adhesive rate, enhanced ICAM-1 protein level, and inhibited migration of endothelial cells and activation of Akt/eNOS pathway in endothelial cells cultured under high-glucose condition. Sphingosine kinase-1 inhibitor, which reduced S1P content, significantly improved the above endothelial cell function indexes and restored the activation of Akt/eNOS pathway. CONCLUSION: S1P promoted high glucose-induced dysfunction of endothelial cells probably by inhibiting the activation of Akt/eNOS signal pathway. Targeting S1P is expected to become one of potential treatment strategies to reduce endothelial cell dysfunction.     

Influence of Sini decoction on the proliferation and apoptosis of artery smooth muscle cells after balloon injury

AIM: To investigate the influence of Sini decoction (SND) on the proliferation and apoptosis of rabbit abdominal aorta smooth muscle cells after ballon injury and discuss the effect of vascular smooth muscle cell's (VSMCs) proliferation and apoptosis in post-percutaneous coronary intervention (PCI) restenosis (RS) and the feasibility of SND preventing post-PCI RS. METHODS: The animal model of rabbit abdominal aorta ballon injury was set up and the therapertic group was treated with SND. The shape of proliferative and apoptotic cell were investigated by electron microscope. Immunohistochemistry staining was performed using α-actin,PCNA and Cyclin E monoclonal antibodies. In situ Cell Death Detection Kit was used to identify apoptotic cells. Abdomial aorta angiography was operated in the 84th day subgroup and the stenosis degree was evalued by quantitative angiographic analysis. RESULTS: As compared with the control group, the therapeutic group displayed a lower proliferative percentage and a higher apoptosic percentage (P<0.05). Moreover, the apoptosic peek time was on the 14th day after operation,which was longer than the control group. CONCLUSION: SND effectly inhibited the proliferation of VSMCs and iuduced apoptosis in VSMCs.     

BYHWD promotes endothelial progenitor cells to repair damaged vascular endothelium

AIM: To investigate the role of Buyanghuanwu decoction (BYHWD) in promoting endothelial progenitor cells (EPCs)-induced recovery of damaged vascular endothelium. METHODS: The endothelial damaged rats were lavaged with BYHWD and injected with EPCs through vena caudalis. The repaired situation of damaged endothelium was observed. RESULTS: Compared with EPCs group and BYHWD group, the endothelial thickness was reduced, the levels of calcium, triglycerides and total cholesterol were decreased, but the high density lipoprotein levels were increased. In addition, the protein expression of vascular endothelial nitric oxide synthase and vascular stromal cell-drived factor-1 was sig-nificantly increased, but the expression of CXC chemokine receptor-4 was significantly reduced in BYHWD+EPC group. CONCLUSION: BYHWD promotes EPCs repairing damaged endothelium, the mechanism may be related to improve the internal environment and promotes the EPCs homing.     

Role of caveolin-1 on down-regulation of LPS-induced monocyte chemotactic protein 1 by 17β-estradiol in vascular smooth muscle cells

AIM: To elucidate the effect of caveolin-1 on the down-regulation of LPS-induced monocyte chemotactic protein 1 (MCP-1) by 17β-estradiol (E₂) in vascular smooth muscle cells (VSMCs).METHODS: The primary-cultured VSMCs were exposed to E₂ at concentrations of 10^-9-10^-6 mol/L. LPS-induced MCP-1 production was assayed by ELISA. The protein expression of caveolin-1 was determined by Western blotting and was silenced by β-methyl cyclodextrin(β-MCD) or caveolin-1 specific siRNA. RESULTS: LPS significantly enhanced MCP-1 production. E₂ at concentrations of 10^-9-10^-6 mol/L inhibited LPS-induced MCP-1 production. The use of caveolin-1 inhibitor β-MCD or silencing the protein expression of caveolin-1 by specific siRNA largely impaired LPS-enhanced MCP-1 production, while E₂ markedly inhibited caveolin-1 expression. CONCLUSION: Inhibition of LPS-induced MCP-1 production by E₂ is related to the suppression of caveolin-1.     

Shear stress regulates NO production in vascular endothelial cells through Pim1/eNOS signaling pathway

AIM: To determine whether laminar shear stress regulates nitric oxide (NO) production in vascular endothelial cells through Pim1/endothelial nitric oxide synthase (eNOS) signaling pathway. METHODS: Human umbilical vein endothelial cells (HUVECs) were exposed to laminar shear stress using a parallel-plate flow system. NO production is evaluated by NO assay kit. Pim1 protein expression and eNOS phosphorylation were determined by Western blot. A specific small interfering RNA was used to knock down Pim1 gene expression, and then the changes of above indicators were detected. RESULTS: After 15-min exposure of HUVECs to laminar shear stress (15 dyn/cm²), rapid increases in Pim1 protein expression and NO production were observed (P < 0.05). Shear stress also caused time-dependent stimulation of eNOS phosphorylation (P < 0.05). The shear-induced Pim1 expression and NO production were abrogated in the HUVECs transfected with siPim1 (P < 0.05). Pim1 silencing also prevented shear-induced rise of eNOS-Ser1177 phosphorylation (P < 0.05). CONCLUSION: Pim1 may account for shear-induced NO production in endothelial cells due to phosphorylation activation of eNOS.     

Rb1 protects human umbilical vein endothelial cells from hydrogen peroxide-induced senescence:involvement of caveolin-1

AIM: Endothelial cell senescence has been proposed to be involved in endothelial dysfunction and atherogenesis. This study aims to investigate the effects of ginsenoside Rb1, a major constituent of ginseng, on hydrogen peroxide (H₂O₂)-induced endothelial cell senescence, and to explore the expression and production of caveolin-1 in H₂O₂-induced premature senescence.METHODS: The senescence of primary human umbilical vein endothelial cells (HUVECs) was induced by H₂O₂ as judged by morphology inspection, senescence-associated β-galactosidase (SA-β-Gal) staining and cell cycle detection. The protein expression of caveolin-1 was determined by Western blot and confocal laser-scanning microscopy.RESULTS: Treatment of the HUVECs with H₂O₂ at 60 μmol/L induced premature senescence, as judged by enlarged, flattened cell morphology, increased SA-β-Gal activity and sustained growth arrest. H₂O₂ effectively increased caveolin-1 level. Pretreatment of the HUVECs with Rb1 was found to reverse endothelial cell senescence, as witnessed by a significant decrease in senescent cell numbers and a decreased percentage of G₀/G₁ phase cells. Furthermore, Rb1 administration reversed the H₂O₂-increased protein level of caveolin-1.CONCLUSION: Ginsenoside Rb1 antagonizes H₂O₂-induced endothelial cell senescence through caveolin-1 modulation.     

Effects of Danggui Buxue decoction on endothelial progenitor cells,serum VEGF and SDF-1 in atherosclerotic rabbits

AIM: To investigate the effects of Danggui Buxue decoction (DBD) on serum vascular endothelial growth factor (VEGF) and stromal cell-derived factor 1 (SDF-1), as well as the activity of circulating endothelial progenitor cells (EPCs) in atherosclerotic rabbits. METHODS: The model of atherosclerosis was established using immune injury and fatty diet for 4 weeks in New Zealand rabbits (n=25). All modeled rabbits were randomized into 5 groups with 5 animals in each group. The rabbits in atherosclerosis group were intragastrically administered with distilled water. The rabbits in simvastatin group were treated with simvastatin at the dose of 1.7 mg/kg. The rabbits in DBD high-dose, middle-dose and low-dose treatment groups were given DBD at the doses of 6 g/kg, 3 g/kg and 1.5 g/kg, respectively. All drugs were given once a day for 2 weeks. After treatment, the levels of serum VEGF and SDF-1 were measured. The mononuclear cells isolated from the rabbit peripheral blood were cultured for 7 days in vitro, and then attached cells were cultured with both DiI-ac-LDL and FITC-UEA-1 for identification. The proliferation was detected by MTT method. The cell migration was observed using Transwell chambers. The adhesion determination and in vitro angiogenesis assay were also performed. RESULTS: Compared with atherosclerosis group, the levels of serum VEGF and SDF-1 were elevated (P<0.05), the proliferation, migration, adhesion and angiogenesis of EPCs were all improved in DBD high-dose, middle-dose treatment groups and simvastatin group (P<0.05). CONCLUSION: DBD elevates the levels of serum VEGF and SDF-1 to improve the activity of EPCs in the process of atherosclerosis.     

Effects of eplerenone on expression and activity of aortic endothelial nitric oxide synthase in hypertensive rats induced by high-salt intake

AIM: To explore the effects of eplerenone on the expression and activity of aortic endothelial nitric oxide synthase(eNOS) in high salt-induced hypertensive rats.METHODS: Male Wistar rats(4 week old, weighting 50～60 g) were randomly divided into control group, high-salt diet group and eplerenone group. The rats in control group were fed with ordinary rodent animal diet, the rats in high-salt group and eplerenone group were exposed to 5% salt diet for 16 weeks and administrated with the same dosage of saline or eplerenone(40 mg·kg^-1·d^-1) by gavage for 4 weeks, respectively. Systolic blood pressure(SBP) was measured by tail-cuff every 2 weeks. The rats were sacrificed after 16 weeks and the thoracic aorta was collected. The aldosterone content in the aorta was measured by ELISA. The protein levels of mineralocorticoid receptor(MR) and eNOS were determined by Western blot. The activitie of constitutive NOS(cNOS) was measured by chemocolorimetry. The protein localization of eNOS, neuronal nitric oxide synthase(nNOS) and MR was observed by immunohistochemistry.RESULTS: A process of 8-week high-salt diet increased SBP gradually. SBP in the rats exposure to high salt for 16 weeks was significantly higher than that in control group(P<0.05). After 4 weeks of eplerenone treatment, SBP in the rats was significantly lower than that before treatment(P<0.05). Compared with control group, the aldosterone content in the aorta were significantly increased in high-salt diet group and eplerenone group(P<0.05), the expression level of MR also increased significantly(P<0.05). Compared with control group, both eNOS protein expression(P<0.05) and cNOS activity in high-salt diet group were significantly decreased(P<0.05). The protein expression of eNOS as well as cNOS activity in aorta increased significantly in eplerenone group compared with high-salt diet group(P<0.05).CONCLUSION: Aldosterone content in aorta of high-salt-induced hypertensive rats increases significantly. Aldosterone attenuates the protein expression of eNOS and reduces the enzyme activity through the activation of mineralocorticoid receptor. The selective mineralocorticoid receptor antagonist eplerenone enhances the protein expression of eNOS and its activity, thereby improves eNOS function.     

Inhibitory effect of Wendan decoction on atherosclerotic plaque formation in ApoE-/- mice by regulating expression of membrane proteins involved in reverse cholesterol transport

AIM To explore the anti-atherosclerotic mechanism of Wendan decoction based on reverse cholesterol transport. METHODS Eight-week-old apolipoprotein E gene knockout （ApoE^-/-） mice with high-fat diet and daily drug gavage were randomly divided into model group, simvastatin group, and low-, middle- and high-dose Wendan decoction groups, with 15 mice in each group. The C57BL/6 mice of the same age served as control group. The mice were weighed once every week. After 10 weeks, the mice were anesthetized with chloral hydrate. The serum were collected for lipid level examination. The atherosclerotic plaque buildup in aortic root and whole aorta was observed by HE staining and oil red O staining, respectively. The levels of proteins related to cholesterol transport, ATP-binding cassette transporter A1 （ABCA1） and caveolin-1 in the aorta, and scavenger receptor class B type I （SR-BI） and CD36 in the liver, were quantified by Western blot. RESULTS Wendan decoction at middle dose inhibited the increase in the body weight of ApoE^-/- mice fed with high-fat diet （P<0.05）. Wendan decoction at different doses significantly reduced the serum levels of triglyceride, total cholesterol and low-density lipoprotein cholesterol in the ApoE^-/- mice （P<0.05 or P<0.01）, but had no effect on serum high-density lipoprotein cholesterol level （P>0.05）. Wendan decoction at different doses inhibited the formation of atherosclerotic plaques in whole aorta of the ApoE^-/- mice （P<0.05 or P<0.01）. Middle- and high-dose Wendan decoction significantly inhibited the formation of atherosclerotic plaques in the aortic root （P<0.05）. Bedsides, Wendan decoction at different doses increased the protein level of ABCA1 and decreased the protein level of caveolin-1 in the aorta of the ApoE^-/- mice （P<0.01）. Middle- and high-dose Wendan decoction increased the liver protein level of SR-BI in the ApoE^-/- mice （P<0.01）. However, Wendan decoction at different doses had no effect on the liver protein level of CD36 in the ApoE^-/- mice （P>0.05）. CONCLUSION Wendan decoction reduces the body weight, serum lipid levels and formation of atherosclerotic plaques in ApoE^-/- mice fed with high-fat diet, and its mechanism is related to up-regulation of ABCA1 protein level in the aorta and SR-BI protein level in the liver as well as down-regulation of caveolin-1 protein level in the aorta.     

Role of homocysteine in tissue factor expression in human vascular smooth muscle cells

AIM: To investigate the expression of tissue factor (TF) induced by homocysteine (Hcy) and the effect of Hcy on activation of nuclear factor-κB (NF-κB) in human vascular smooth muscle cells (VSMCs).METHODS: Human umbilical artery VSMCs were cultured by tissue explanting method,and were incubated with different dosage of Hcy/ PDTC (NF-κB inhibitor) in different time.RT-PCR was used to measure the expression of TF mRNA,and flow cytometry was used to detect the expression of TF on the surface of VSMCs.Western blotting was performed to measure the NF-κB protein level in the nuclear,flow cytometry was used to examine the expression of iNOS and the expression of TF on the surface of VSMCs.RESULTS: Hcy induced VSMCs TF mRNA expression significantly after the VSMCs were incubated with Hcy at concentrations of 10,100,500 μmol/L,respectively.There was low expression level of TF protein on the surface of the control VSMCs and Hcy also induced VSMCs TF protein expressionn on the cell surface at different concentrations.Additionally,Hcy rapidly induced the activation of NF-κB and inhibited this effect significantly by PDTC.Hcy alone did not induce the expression of iNOS in VSMCs.CONCLUSION: Hcy induces human VSMCs expression of TF in mRNA and protein.These effects were partly mediated by NF-κB.These results suggest that Hcy may play an important role in atherosclerosis and thrombosis.     

Hypoxia-induced caveolin-1 up-regulation is involved in migration and invasion of lung adenocarcinoma A549 cells

AIM:To investigate the regulatory role of hypoxia mimic reagent cobalt chloride (CoCl2) on caveolin-1 (Cav-1) generation and the influence of Cav-1 on the abilities of migration and invasion of human lung adenocarcinoma A549 cells. METHODS:The concentrations of Cav-1 and hypoxia-inducible factor (HIF)-1α in pleural effusion of the patients with lung cancer (MPE) or tuberculous pleurisy (TBPE) were detected, and the correlation was also compared. A549 cells were treated with CoCl2 at different concentrations and time in the presence or absence of HIF-1α inhibitor YC-1. The concentrations of Cav-1 and HIF-1α in the cell supernatants were measured by ELISA. The effects of Cav-1 induced by CoCl2 on the migration and invasion of A549 cells were determined by scratch test and Transwell invasion trial, respectively. RESULTS:The levels of Cav-1 and HIF-1α in MPE were significantly higher than those in TBPE. There was a highly positive correlation between Cav-1 and HIF-1α levels in the pleural effusion. CoCl2 induced the generation of Cav-1 and HIF-1α in A549 cells in a concentration- and time-dependent manner, the peak occurred at 200 μmol/L or 24 h, while the concentration over 200 μmol/L or after treated over 24 h, a concentration- or time-dependent inhibition was observed. HIF-1α inhibitor YC-1 concentration-dependently inhibited the generation of HIF-1α and Cav-1 induced by CoCl2 in A549 cells. CoCl2 enhanced A549 cells migration and invasion, with 200 μmol/L played the strongest role, which were down-regulated significantly in the presence of YC-1. CONCLUSION: The alteration of hypoxia-induced Cav-1 generation might be involved in the migration and invasion of A549 cells. A possible role for HIF-1α is indicated in Cav-1 generation.     

Effects of LPS on expressions of ET-1, eNOS and iNOS mRNA in human umbilical vein endothelial cells

AIM: To observe the direct effect of LPS on expressions of ET-1, eNOS, and iNOS mRNA in human umbilical vein endothelial cells, and further research the molecular mechanism of effect of LPS on production of ET-1 and NO. METHODS:The third passage of cultured human umbilical vein endothelial cells was incubated with low concentration (100 μg/L) of LPS for 6 h. Total RNA was extracted. The expressions of ET-1, eNOS, and iNOS mRNA were analyzed by semi-quantitative RT-PCR method. RESULTS: ET-1 mRNA experession increased significantly, while expression of eNOS mRNA decreased significantly, and there was no significant change in expression of iNOS mRNA. CONCLUSION: In human umbilical vein endothelial cells, low concentration of LPS enhanced the expression of ET-1 mRNA, inhibited the expression of eNOS mRNA, and had no significant effect on the expression of iNOS mRNA.