ObjectiveTo compare the different effects of ubiquitin(UB) on human umbilical vein endothelial cells (HUVECs) and macrophages under normal circumstances,and analyze whether UB could protect HUVECs from lipopolysaccharide(LPS) induced injury. MethodsThe morphologic changes of HUVECs in vitro with up-rising concentrations of UB interventions were observed. HUVECs and human macrophages in vitro were divided into 4 groups according to UB concentration (0.01 μg/mL,0.1 μg/mL, 1 μg/mL, and 10 μg/mL). Supernatant and cells of each group were collected in 24 h after UB intervention. The levels of TNF-α and VCAM-1 in supernatant were measured by ELISA while NF-κB protein level in cells was detected by Western blot. HUVECs were divided into a LPS group(LPS 10 μg/mL) and an UB+LPS group(UB 0.1 μg/mL,LPS 10 μg/mL). The supernatant of the two groups were collected in 8,16 and 24 h after LPS and UB intervention. The levels of TNF-α and VCAM-1 in supernatant were measured by ELISA. ResultsThe injury of HUVECs got worse with the ascending concentrations of UB.At the concentration of 50 μg/mL,UB induced HUVECs got ballooned and died massively. With the increase of UB concentration,the levels of TNF-α and VCAM-1 in HUVECs' supernatant ascended firstly and then descended,while those in human macrophages' supernatant ascended gradually. zHowever,the tendency of the NF-κB protein level in the two kinds of cells was similar when the concentration of UB increased.At the consentration of 0.1 μg/mL or 1 μg/mL,ubiquitin induced NF-κB protein level obviously increased.At the concentration of 0.01 μg/mL or 10 μg/mL,UB induced the protein level was similar with those of the control group and even decreased slightly. There was no significant difference in TNF-α or VCAM-1 levels at each time point between the LPS group and the UB+LPS group. ConclusionsUB injuries HUVECs obviously at a low concentration but injuires human macrophages at much higher concentraton. UB can not protect HUVECs from LPS-induced injury in vitro.
ObjectiveTo study the protective effect and mechanism of ophiopogonin D (OP-D) on lipopolysaccharide induced acute lung injury (ALI) in mice.MethodsFifty SPF C57BL/6 mice were randomly divided into five groups, ie. a control group, a sham operation group, a model group, an OP-D group (10 mg·kg–1·d–1), and a dexamethasone group (2 mg·kg–1·d–1), with 10 mice in each group. One day before the establishment of the model, the OP-D group and the dexamethasone group received the corresponding drugs by gavage. The model group, the OP-D group and the dexamethasone group received lipopolysaccharide (2 mg/kg, 30 μL) through the trachea to establish the ALI model. The sham operation group received the same volume of normal saline. The blank control group was not treated. Six hours after the operation, the mice were weighed and then killed for peripheral blood and lung tissue. The weight of lung tissue was measured to evaluate the degree of pulmonary edema; the pathological changes of lung tissue were observed by hematoxylin-eosin staining; the mRNA expressions of interleukin (IL)-6, IL-10, and IL-17 in lung tissue were detected by qPCR; the percentage of Th17 and Treg cells in peripheral blood was detected by flow cytometry.ResultsCompared with the model group, the degree of pulmonary edema in the OP-D group decreased significantly (P<0.05), the lung tissue injury decreased, the mRNA expressions of IL-6 and IL-17 in the lung tissue and the proportion of Th17 cells in the peripheral blood decreased significantly (P<0.05), the proportion of Treg cells in the peripheral blood and the mRNA expression of IL-10 in the lung tissue increased significantly (P<0.05).ConclusionOP-D may have therapeutic effect on LPS induced ALI in mice by regulating the balance of Th17/Treg cells.
Objective To investigate the effect of microRNA-27a (miR-27a) on the apoptosis of human lung adenocarcinoma cells A549 induced by lipopolysaccharide (LPS) by regulating the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) pathway, and its mechanism is discussed preliminarily. Methods The complementary binding sites of miR-27a and phosphatidylinositol-3 kinase catalytic subunit delta (PIK3CD) were analyzed by Starbase and verified by double luciferase. The A549 cells were divided into normal group, LPS group, LPS+miR-27a mimic negative control group, LPS+miR-27a mimic group, LPS+miR-27a mimic+PI3K activator group. In the LPS+miR-27a mimic negative control group, LPS+miR-27a mimic group and LPS+miR-27a mimic+PI3K activator group, the cells were transfected with miR-27a mimic negative control, miR-27a mimic and miR-27a mimic, respectively, and were cultured for 6 h. After that, the cells were cultured in complete medium for 24 h, and then, except for the normal group, the cells in the other groups were stimulated with 10 mg/L LPS for 24 h, and the PI3K activator 740 Y-P was added to the LPS+miR-27a mimic+PI3K activator group, and cells in normal group were cultured in complete medium for the same time. Real-time quantitative polymerase chain reaction was used to detect the expression level of miR-27a in cells; cell counting kit 8 was used to detect cell proliferation; Hoechst33342 staining and flow cytometry was used to detect apoptosis; autophagy of A549 cells was observed by transmission electron microscope; Western blot was used to detect the expression of PIK3CD, phosphorylated-AKT (p-AKT), B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), cleaved caspase-3 and microtubule-associated protein 1 light chain 3 II (LC3II) protein. Results There was a binding site between miR-27a and PIK3CD, which was verified by double luciferase. Compared with those in normal group, the expression level of miR-27a, proliferation rate and protein expression level of Bcl-2 in LPS group and LPS+miR-27a mimic negative control group were lower (P<0.05), the apoptosis rate, protein expression levels of PIK3CD, p-AKT, Bax, cleaved caspase-3, LC3Ⅱ were higher (P<0.05); compared with those in LPS group and LPS+miR-27a mimic negative control group, the expression level of miR-27a, proliferation rate and protein expression level of Bcl-2 in LPS+miR-27a mimic group were higher (P<0.05), the apoptosis rate, protein expression levels of PIK3CD, p-AKT, Bax, cleaved caspase-3, LC3Ⅱ were lower (P<0.05); compared with those in LPS+miR-27a mimic group, the expression level of miR-27a and proliferation rate in LPS+miR-27a mimic+PI3K activator group were lower (P<0.05), the apoptosis rate, protein expression levels of PIK3CD, p-AKT, cleaved caspase-3, LC3Ⅱ were higher (P<0.05). The number of cells in the normal group was more, the cells were closely arranged, the nucleus size was uniform, and the organelle structure was normal; in LPS group and LPS+miR-27a mimic negative control group, cells became round, nuclei pyknosis, formed clumps, and showed multiple round autophagic vesicles of different sizes; the number of nuclear pyknotic cells in LPS+miR-27a mimic group decreased, and the number of nuclear pyknotic cells in LPS+miR-27a mimic+PI3K activator group increased compared with LPS+miR-27a mimic group, a small number of circular autophagic vesicles were observed, but the number was different. Conclusion Overexpression of miR-27a can inhibit PI3K/Akt pathway and reduce LPS induced apoptosis of human lung adenocarcinoma cells A549, which may be related to the reduction of autophagy.
Objective To detect the effects of cytokines on the expression of early growth response gene-1 (Egr-1) in cultured human retinal pigment epithelial (RPE) cells. Methods Immunofluorescence staining, Western blotting and reverse transcription polymerase chain reaction (RT-PCR) were used to detect and quantitatively analyze the expression of Egr-1 protein and mRNA in cultured human RPE cells which were exposed to stimulants, including 20 mu;g/ml lipopolysaccharide (LPS), 40 ng/ml tumor necrosis factor (TNF)-alpha;, 10 U/ml interferon (IFN)gamma;, 30% supernatant of monocyte/macrophage strain (THP1 cells) and the vitreous humor from healthy human eyeballs, for 0, 10, 20, 30, 40 and 60 minutes, respectively. Results The RPE cells stimulated for 0 minute revealed faint green fluorescence of Egr-1 in the cytoplasm. With exposure to the stimulants, the expressionof Egr-1 increased obviously and b green fluorescence was found in cytoplasm in some nuclei of RPE cells. Compared with the untreated RPE cells, after stimulated by 20 mu;g/ml LPS, 40 ng/ml TNFalpha;, 10 U/ml IFNgamma;, 30% supernatant of THP-1 cells and the vitreous humor, the approximate ultimate amplitudes of Egr-1 mRNA enhanced 1.9, 1.3, 14, 1.2, and 1.4 times, respectively; the greatest amplitudes of Egr-1 protein increased 3.4, 1.2, 1.7, 32, and 1.3 times, respectively. Conclusion LPS, TNF-alpha;, IFN-gamma;, supernatant of THP-1 cells and the vitreous humor can upregulate the expression of Egr-1 mRNA and protein in cultured human RPE cells, and induce its nuclear transposition, which suggests the activation of Egr-1.
ObjectiveTo evaluate the combination of lipopolysaccharide-amine nanopolymersomes (LNPs), as a gene vector, with target gene and the transfection in bone marrow mesenchymal stem cells (BMSCs) so as to provide a preliminary experiment basis for combination treatment of bone defect with gene therapy mediated by LNPs and stem cells. MethodsPlasmid of bone morphogenetic protein 2 (pBMP-2)-loaded LNPs (pLNPs) were prepared. The binding ability of pLNPs to pBMP-2 was evaluated by a gel retardation experiment with different ratios of nitrogen to phosphorus elements (N/P). The morphology of pLNPs (N/P=60) was observed under transmission electron microscope (TEM) and atomic force microscope (AFM). The size and Zeta potential were measured by dynamic light scattering (DLS). The resistance of pLNPs against DNase I degradation over time was explored. The viability of BMSCs, transfection efficiency, and expression of target protein were investigated after transfection by pLNPs in vitro. ResultsAt N/P≥1.5, pLNPs could completely retard pBMP-2; at N/P of 60, pLNPs was uniform vesicular shape under AFM; TEM observation demonstrated that pLNPs were spherical nano-vesicles with the diameter of (72.07±11.03) nm, DLS observation showed that the size of pLNPs was (123±6) nm and Zeta potential was 20 mV; pLNPs could completely resist DNase I degradation within 4 hours, and such protection capacity to pBMP-2 decreased slightly at 6 hours. The cell survival rate first increased and then decreased with the increase of N/P, and reached the maximum value at N/P of 45; the cytotoxicity was in grade I at N/P≤90, which meant no toxicity for in vivo experiment. While the transfection efficiency of pLNPs increased with the increase of N/P, and reached the maximum value at N/P of 60. So it is comprehensively determined that the best N/P was 60. At 4 days, transfected BMSCs expressed BMP-2 continuously at a relatively high level at N/P of 60. ConclusionLNPs can compress pBMP-2 effectively to form the nanovesicles complex, which protects the target gene against enzymolysis. LNPs has higher transfection efficiency and produces more amount of protein than polyethylenimine 25k and Lipofectamine 2000.
ObjectiveTo investigate the mechanism of lung tissue apoptosis in LPS-induced mice ARDS via TNF-α neutralization. MethodsThirty-six mice were randomly divided into a control group,a LPS group,and TNF-α neutralization group.LPS(5 mg/kg) was intratracheally nebulized to induce ARDS in the LPS group and the TNF-α neutralization group.Twenty-four hours before LPS treatment,etanercept (0.4 mg/kg) was abdominal injected to the mice in the TNF-α neutralization group.Mice were sacrificed 2 hours after LPS treatment.PCR were used to detected the expression of NF-κB p65,Bax and Bcl-2 in lung tissue.Western blot were used to detected protein level of NF-κB p65,Erk1/2 and their phosphorylation and Bax,Bcl-2.The lung dry-to-wet ratio was measured.The lung histological changes were evaluated by HE staining. ResultsActivation level of NF-κB p65 and Erk1/2 was elevated,the ratio of Bcl-2 and Bax was decreased in the LPS group(P<0.05).After TNF-α neutralization,the activation level of NF-κB p65 and Erk1/2 were reduced,the ratio of Bcl-2 and Bax was increased (P<0.05).Compared with the LPS group,the lung dry-to-wet ratio and lung injury semi-quantitative score were significantly decreased in the TNF-α neutralization group (P<0.05). ConclusionTNF-α neutralization can suppress lung injury in LPS-induced ARDS mice by inhibiting activation of NF-κB p65 and Erk1/2,increasing the ratio of Bcl-2 and Bax ratio,and eventually reducing apoptosis.
ObjectiveTo investigate the effect of curcumin on lipopolysaccharide (LPS)-induced inflammation and apoptosis in alveolar macrophage via microRNA-132 (miR-132)/high mobility group protein B1 (HMGB1).MethodsThe cultured mouse alveolar macrophage line (RAW264.7 cells) were divided into the control group, the LPS group, the LPS+50 μmol/L curcumin group, and the LPS+100 μmol/L curcumin group. Forty-eight hours after drug treatment, the levels of miR-132/HMGB1, inflammatory mediator and apoptotic were detected. Secondly, the empty vector, synthetic miR-132 mimics and inhibitors were transfected into another cultured mouse alveolar macrophage line (RAW264.7 cells) to detect the inflammation and apoptosis of alveolar macrophage after transfection.ResultsCompared with the control group, in the LPS group, the apoptosis of alveolar macrophage, the levels of interleukin (IL)-6, IL-8 and tumor necrosis factor (TNF)-α, and the expression of miR-132 increased, while the expression of HMGB1 decreased (P<0.05); compared with the LPS group, in the two curcumin groups, the apoptosis of alveolar macrophage, the levels of IL-6, IL-8 and TNF-α, and the expression of miR-132 decreased, while the expression of HMGB1 increased (P<0.05); and the greater the drug concentration, the more obvious the effect (P<0.05). In addition, up-regulation of miR-132 reduced the expression of HMGB1 in alveolar macrophage, increased inflammatory factor, and induced apoptosis in alveolar macrophage; however, down-regulation of miR-132 increased the expression of HMGB1 in alveolar macrophage, reduced inflammatory factor, and inhibited apoptosis in alveolar macrophage (P<0.05).ConclusionCurcumin could decrease LPS-induced inflammation and apoptosis in alveolar macrophage via decreasing miR-132 and increasing HMGB1.
ObjectiveTo observe the effects of perindopril on expression level of phosphatidylinositol 3-kinase (PI3K) and lung function in rats with obstructive pulmonary disease (COPD),and investigate the therapeutic effects of perindopril on COPD. MethodsSixty male SD rats were randomly divided into a control group,a COPD group,and a perindopril group,with 20 rats in each group. The rat model of COPD was established by intratracheal instillation of lipopolysachride and exprosure to cigarette smoke in the COPD group and the perindopril group. The rats in the perindopril group were intragastricly infused with perindopril additionally. All rats were sacrificed after 28 days. The lung function was observed and PI3K protein expression was detected using Western blot method. The pathologic changes of the lung tissue and airway were observed by HE staining. ResultsHE staining revealed that the rat COPD model was successfully established. The COPD group appeared obvious emphysema which was allievated significantly in the perindopril group. Pulmonary function indices in the COPD group and the perindopril group were significantly decreased compared with the control group with VE value decreased by 40% and 22%,PEP value decreased by 33% and 15%,and FEV0.3 value decreased by 18% and 7%,respectively. The expression of PI3K was significantly increased in the COPD group and the perindopril group than the control group,but more significantly in the COPD group (P<0.05). ConclusionPerindopril can significantly improve lung function in rats with COPD possibly through down-regulation of PI3K expression in the lung.
Objective To investigate the influence of lipopolysaccharide(LPS) on the proliferation and collagen synthesis of normal human skin fibroblasts so as to elucidate its relation with skin wound healing. Methods Fibroblasts wereisolated and cultured in vitro, and then exposed to different doses of LPS(0.005, 0.010, 0.050, 0.100, 0.500, and 1.000 μg/ml) from E.coli055∶B5 respectively. Then the absorbance (A) value of fibroblasts was determined with the colorirneteric thiazolylblue (MTT) assay, and the cell number was counted under inverted phase contrast microscope from the 1st day to the 9th day after LPS administration, and collagen synthesis of fibroblasts in culture medium was measured with the method of pepsin digestion after incorporation of 3Hproline into stable, single-layered, confluent fibroblasts at 7 days after LPS administration. Results Compared with control group, A value increased with the increasing concentration of LPS (0.005 μg/ml 0.500 μg/ml) and LPS of 0.100 μg/mlgroup had the best effect. The difference was remarkable from the 5th day to the 9th day(P＜0.05). A value decreased when challenged with the LPS of 1.000 μg/ml and the difference was remarkable from the 3rd day to the 9th day(P＜0.05). Cell number increased with theadministration of LPS of different concentrations (0.005 μg/ml 0.500 μg/ml) and LPS of 0.100 μg/mlgroup had the best effect. The difference was remarkable from the 1st day to the 6th day(P＜0.05). Cell number decreased remarkably when challenged with LPS of 1.000 μg/ml and the difference was remarkable from the 2nd day to the 9th day(P＜0.05). Collagen synthesis increased when challenged with LPS of different concentrations (0.005 μg/ml 0.500 μg/ml) and the 0.100 μg/ml group had the best effect. However, when the dose of LPS reached 1.000 μg/ml, it inhibited collagensynthesis. Conclusion LPS could promote the proliferation andcollagen synthesis of fibroblasts within a certain range of low doses, but over-high dose ofLPS might inhibit the proliferation and collagen synthesis of fibroblasts, suggesting that LPS of certain concentrations might contribute to wound healing, while excessive LPS has negative effect on wound healing.
ObjectiveTo investigate the correlations between tumor necrosis factor-α (TNF-α) and lipopolysaccharide (LPS) with acute myocardial dysfunction after severe thoraco-abdominal injuries and possible mechanisms. MethodsClinical data of 82 patients with severe thoraco-abdominal injuries who were admitted to the 253rd Hospital of People's Liberation Army from January 2009 to June 2012 were retrospectively analyzed,whose trauma index (TI) were all above or equal to 17 points. Patients with concomitant brain injuries and patients who were brought in dead were excluded from this study. There were 58 male and 24 female patients with their age of 16-76 (43.59±16.33) years. There were 17 patients with open injuries and 65 patients with closed injuries. There were 23 patients with fall injuries,47 patients with traffic injuries,8 patients with blunt injuries,and 4 patients with penetrating injuries. The time from injury to admission was 1.51±0.52 hours. Blood creatine kinase-MB (CK-MB) cardiac troponin T (cTnT) TNF-α and LPS were examined during emergency treatment,and the correlations between the results were analyzed. ResultsMyocardial dysfunction was shown by CK-MB of 158.74±31.59 U/L and cTnT of 496.25±58.46 pg/ml. Injury factors were TNF-α of 36.41±18.09 ng/ml and LPS of 343.66±106.02 U/L. CK-MB was positively correlated with TNF-α and LPS with the correlation coefficient (r) of 0.923 1and 0.883 2 respectively. cTnT was also positively correlated with TNF-α and LPS with r of 0.955 6 and 0.889 1 respectively. ConclusionBoth TNF-α and LPS participate in the pathogenesis and development of acute myocardial dysfunction after severe thoraco-abdominal injuries. Early intervention against TNF-α and LPS may alleviate acute myocardial dysfunction and improve patients' survival rate after severe thoraco-abdominal injuries.