Objective To investigate the relationship of pulmonary surfactant protein D( SP-D) with chronic obstructive pulmonary disease ( COPD) by measuring SP-D level in serum and lung tissue of rats with COPD.Methods The rat COPD model was established by passive smoking as well as intratracheal instillation of lipopolysaccharide ( LPS) . Thirty male SD rats were randomly divided into a control group, a LPS group, and a COPD group( n =10 in each group) . The pathologic changes of lung tissue and airway were observed under light microscope by HE staining. Emphysema changes were evaluated by mean linear intercept ( MLI) of lung and mean alveolar number ( MAN) . The level of SP-D in serum was measured by enzymelinked immunosorbent assay ( ELISA) . The expression of SP-D in lung tissue was detected by Western-blot and immunohistochemistry.Results The MLI obviously increased, and MAN obviously decreased in the COPD group compared with the control group ( Plt;0.05) . There was no significant difference in the MLI and MAN between the LPS group and the control group ( Pgt;0.05) . The serum SP-D level was ( 49.59 ±2.81) ng/mL and ( 53.21±4.17) ng/mL in the LPS group and the COPD group, which was significantly higher than that in the control group [ ( 42.14±2.52) ng/mL] ( Plt;0.05) . The expression of SP-D in lung tissue was 0.56±0.01 and 0.63±0.01 in the LPS group and the COPD group, which was also obviously ber than that in the control group ( 0.39 ±0.01) ( Plt;0.05) .Meanwhile the SP-D levels in serumand lung tissue were higher in the COPD group than those in the LPS group ( Plt;0.05) . The levels of SP-D between serum and lung tissue were positively correlated in all three groups ( r=0.93, 0.94 and 0.93, respectively, Plt;0.01) .Conclusion Both the SP-D level in serum and in lung tissue increase significantly in COPD rats and correlate well each other, which suggests that SP-D may serve as a biomarker of COPD.
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.
Objective To investigate the transduction pathway of TREM-1 during endotoxininduced acute lung injury ( ALI) in mice through the specific activating or blocking TREM-1.Methods 40 mice were randomly divided into a saline control group, an ALI group, an antibody group, and a LP17 group ( 3.5 mg/kg) . All mice except the control group were intraperitoneally injected with lipopolysaccharide ( LPS) to establish mouse model of ALI. Two hours after LPS injection, anti-TREM-1mAb ( 250 μg/kg) was intraperitoneally injected in the antibody group to activation TREM-1, and synthetic peptide LP17 was injected via tail vein in the LP17 group to blocking TREM-1. After 6,12,24, 48 hours, 3 mice in each group were sacrificed for sampling. The expression of NF-κB in lung tissue was determined by immunohistochemistry. The levels of TNF-α, IL-10, TREM-1, and soluble TREM-1 ( sTREM-1) in lung tissue and serumwere measured by ELISA. Pathology changes of lung were observed under light microscope, and Smith’s score of pathology was compared. Results Administration of anti-TREM-1mAb after ALI modeling significantly increased the NF-κB expression in lung tissue at 48h, resulting in a large number of pro-inflammatory cytokines releasing in the lung tissue and serumand lung pathology Smith score increasing. Administration of LP17 after modeling significantly down-regulated the expressions of NF-κB and pro-inflammatory cytokines, while led to a slight increase of anti-inflammatory cytokines and a decline of lung pathology Smith’s score.Conclusion TREM-1 may involve in inflammatory response by promoting the generation of inflammatory factors via NF-κB pathway, thus lead to lung pathological changes in ALI.
ObjectiveTo investigate the correlations between lipopolysaccharide(LPS), phospholipase A2 (PLA2) and platelet-activating factor (PAF) with coagulopathy after severe chest and abdominal injuries and their mechanisms. MethodsClinical data of 82 patients with severe chest and abdominal injuries whose trauma index (TI) was greater than or equal to 17 points in No. 253 Hospital of People's Liberation Army from January 2009 to June 2012 were retrospectively analyzed (severe chest and abdominal injury group). Those patients who had concomitant traumatic brain injuries or died in the Emergency Department 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 force injuries, and 4 patients with penetrating injuries. Forty-two healthy volunteers who received routine medical examinations in the outpatient department of our hospital were chosen as the control group, including 27 males and 15 females with their age of 24-47 (37.32±10.45) years. Blood platelet (PLT) count, D-dimer (D-D), activated partial thromboplastin time (APTT), LPS, PLA2 and PAF were compared between the 2 groups, and linear correlation analysis was performed. ResultsPLT of the severe chest and abdominal injury group patients were significantly lower than that of the control group[(83.44±38.52)×109/L vs. (191.52±23.31)×109/L]. D-D[(1 823.89±608.02) U/L vs. (105.78±44.53) U/L], APTT [(68.24±24.12) s vs. (22.47±9.41) s], LPS[(438.66±106.02) U/L vs. (87.38±46.51) U/L], PLA2 [(41.35±14.26) ng/ml vs. (7.47±5.27)ng/ml] and PAF[(15 765.31±4 431.65) ng/L vs. (3 823.45±529.72) ng/L] of the severe chest and abdominal injury group patients were significantly higher than those of the control group(P < 0.001). PLT was significantly negatively correlated with LPS, PLA2 and PAF with all the respective correlation coefficient(r)less than-0.933 5. D-D and APTT were significantly positively correlated with LPS, PLA2 and PAF with all the respective r larger than 0.921 6. ConclusionLPS, PLA2 and PAF participate in the pathogenesis of coagulopathy in patients with severe chest and abdominal injuries. Early intervention against LPS, PLA2 and PAF may improve coagulopathy and survival rate of patients with severe chest and abdominal injuries.
Objective To establish a mouse model of acute lung injury ( ALI) and pulmonary fibrosis by low dose lipopolysaccharide ( LPS) intermittent intraperitoneal injection, and to explore the pathogenesis of ALI and pulmonary fibrosis induced by endotoxin. Methods Forty C57BL/6 mice were randomly divided into a control group, a 3-days LPS group, a 2-weeks LPS group, and a 4-weeks LPS group,with 10 mice in each group. LPS was injected intraperitoneally at dose of 5 mg/ kg for three consecutive daysin the three LPS groups. Equivalent normal saline was injected by the same way in the control group. The mice lung tissues were obtained respectively 3 days ( the control group and 3-days LPS group) , 2 weeks ( the 2-weeks LPS group) , and 4 weeks ( the 4-weeks LPS group) after LPS or saline stimulation. HE staining,Van-Gieson collagen staining, and Ashcroft fibrosis score assessment were applied to evaluate the development of inflammation and fibrosis in lung tissue at various stages of ALI after LPS-stimulation. The mRNA expression of type Ⅰ procollagen and alpha smooth muscle actin ( α-SMA) were detected by realtime PCR. The deposition of collagen and fibrosis in lung tissue were detected by hydroxyproline assay. The survival condition of each group was also recorded. Results Acute inflammation occurred in mice lung tissue 3 days after intraperitoneal injection of LPS. Collagen deposited in pulmonary interstitium2 weeks afterLPS-stimulation and formed typical pulmonary interstitial fibrosis 4 weeks later accompanying with increase of Ashcroft fibrosis score. Real-time PCR and hydroxyproline assay showed that the expression of collagen and α-SMA increased 3 days after LPS-stimulation and reached the peak 4 weeks later. The animals were all survived up to the endpoint of experiment. Conclusions Accompanying with inflammation, pulmonary fibrosis initiated at early stage of ALI induced by LPS. Intraperitoneal injection of LPS at dose of 5 mg/kg for three consecutive days was able to establish the mouse model of ALI and pulmonary fibrosis with high successrate and low animal mortality, which provide an ideal experimental platform for further investigation.
Objective To investigate the expression of granulysin ( GNLY) in lung of rats with acute lung injury ( ALI) stimulated with lipopolysaccharide ( LPS) . Methods Thirty-six healthy adult Wistar rats were randomly divided into a normal control group and a LPS group, with 18 rats in each group. LPS ( 4 mg/kg) was given intraperitoneally in the LPS group to induce ALI. The same amount of normal saline was given in the control group. The rats were randomly assigned to three subgroups ( n = 6) to be sacrificed respectively at 6, 18, and 30 hours after intraperitoneal injection. Wet/dry lung weight ratio ( W/D) and pathological changes of the lung were observed. The expression of GNLY in lung tissue was assayed by immunohistochemistry. Results In the LPS group, the W/D ratio was higher than that of the control group at each time point ( P lt;0. 05) and there were a large number of inflammatory cells infiltration and edema in interstitial spaces which suggested ALI. Compared with the control group, the expression of GNLY in the LPS group was significantly increased at all time points ( P lt;0. 05) . Conclusion GNLY may participate in ALI inflammatory process, which might play a role in preventing infection induced ALI.
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.
Objective To investigate whether P12，a kind of lipopolysaccharide（LPS）-binding protein（LBP） inhibitory peptide，could suppress the binding of LPS to alveolar macrophages（AMs） in a mouse model of endotoxemia in vivo.Methods Forty mice were randomly divided into five groups，ie.a control group，an endotoxemia group，a low dose P12-treated group，a middle dose P12-treated group and a high dose P12-treated group.Mouse model of endotoxemia was established by LPS injection intraperitoneally in the endotoxemia group and P12-treated groups.P12 was instilled via the tail vein.The effects of P12 on the binding of LPS to AMs were determined by flow cytometric analysis and quantization by mean fluorescence intensity(MFI).The productions of tumor necrosis factor α(TNF-α) in serum of mice were measured by enzyme-linked immunosorbent assay(ELISA).Results MFI in AMs from low，middle and high dose P12-treated groups was 40.08%，30.76% and 24.45%，respectively，which was higher than that of the control group(4.61%)，but less than that of the endotoxemic mice(45.31%).The concentration of TNF-α in serum of low，media and high dose P12-treated mice was (112.69±19.78)pg/mL，(86.34±9.25) pg/mL，(70.48±8.48)pg/mL respectively，which was higher than that of the control group[(24.88±5.82)pg/mL]，but less than that of the endotoxemic mice[(180.17±39.14)pg/mL].Conclusion The results suggest that P12 inhibit the binding of LPS and AMs，thus reduce the proudction of TNF-α stimulated by LPS.
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.
Objective To explore the protective effects of liver X receptor-αactivator ( LXRα)T0901317 on rats with acute lung injury ( ALI) . Methods Seventy-two male Wistar rats were randomly divided into three goups, ie. a control group, a LPS group, and a T0901317 group. Artery blood gas analysis,lung tissue wet/dry weight ratio,myeloperoxidase activity, and lung histopathological changes were measured.The expressions of LXRαand TNF-αmRNA in lung tissue were detected by RT-PCR. The protein levels ofTNF-αand LXRαwere examined with ELISA and immunohistochemistry, respectively. Results In the ALI rats, PaO2 decreased, lung W/D weight ratio and myeloperoxidase activity increased significantly compared with the control group ( P lt; 0. 05) . Histopathological examination also revealed obvious lung injury. In theLPS group, the expression of TNF-αmRNA in lung tissue and the level of TNF-αprotein in lung homogenate and serum increased markedly( all P lt; 0. 05) while the expression of LXR-αmRNA declined significantly ( P lt; 0. 05) . Immunohistochemical staining showed that lung tissues of the normal rats expressed LXRαsignificantly but in the LPS group the expression of TNF-αand LXR-αin lung tissue decreased markedly ( P lt;0. 05) . After the treatment with T0901317, the expressions of LXR-αin lung tissues were significantly higher than those in the LPS group both at the mRNA and the protein level ( P lt; 0. 05) . Conclusion T0901317 plays an anti-inflammatory effect through up-regulating the expression of LXR-αand suppressing the expression of TNF-α, thus reduces the infiltration and aggregation of inflammatory cells in lung tissue.