Comparisons of coagulation characteristics between elderly and non-elderly patients with sepsis: A prospective study.

BACKGROUND: A blunt host defense response in older patients may contribute to different coagulation responses during sepsis. We aimed to investigate the differences in coagulation parameters between elderly and non-elderly patients with sepsis. METHODS: Adult patients diagnosed with sepsis within 24 hours after admission to the intensive care unit between September 2018 and December 2020 were prospectively enrolled. Patients were categorized into the adult (18-64 years) and elderly (age ≥65 years) groups. Conventional coagulation parameters and inflammatory markers were measured on intensive care unit admission and on Days 3 and 7. Thromboelastography was performed on intensive care unit admission. The differences in the coagulation parameters between the 2 groups were evaluated. The adult and elderly patients were matched to adjust for baseline characteristics. Correlations between inflammatory markers and coagulation-related parameters were also analyzed. RESULTS: Of the 567 patients, 303 (53.4%) were elderly. Compared with adult patients, elderly patients had lower prothrombin time elevation, lower fibrinogen, D-dimer, and fibrin/Fib degradation product levels, and lower proportion of disseminated intravascular coagulation on intensive care unit admission; and, they had lower dynamic platelet, lower fibrinogen, and D-dimer levels during the first week in the intensive care unit. Thromboelastography parameters were generally within the normal range, although elderly patients had lower R and K values and a higher alpha angle. Comparisons of coagulation parameters between the 2 groups revealed similar results in the matched cohort. The inflammatory markers correlated with prothrombin time, activated partial thromboplastin time, and antithrombin III. CONCLUSION: Elderly patients had milder coagulation activation, accompanied by a decreased inflammatory response during sepsis, compared to non-elderly patients.

Unfractionated Heparin Protects Microcirculation in Endotoxemic Rats by Antagonizing Histones.

INTRODUCTION: Levels of extracellular histones are highly increased in sepsis and may facilitate microcirculatory dysfunction. Unfractionated heparin (UFH) binds histones and neutralizes their cytotoxicity. We investigated the effect of UFH on microcirculatory dysfunction by interacting with extracellular histones in endotoxemic rats. METHODS: Twenty-four Wistar rats were randomly divided into three groups: control, lipopolysaccharide (LPS) group, and LPS + UFH group. In the LPS and LPS + UFH groups, 10 mg/kg LPS was injected to induce endotoxemia, and 100 IU/kg/h UFH was administered intravenously in the LPS + UFH group. The rats underwent midline laparotomy, and then intestinal microcirculation was evaluated using an incident dark field microscope. Circulating histones and microstructures of the rat intestinal microvascular endothelium were also detected. Additionally, the antagonistic effect of UFH on histone-induced cytotoxicity was investigated in human intestinal microvascular endothelial cells. RESULTS: UFH protected the microcirculation of the intestinal serosa and mucosa in endotoxemic rats, as evidenced by increased total vessel density, perfused vessel density, and proportion of perfused vessels of both the serosa and mucosa, and increased microcirculatory flow index of the mucosa in the LPS + UFH group. UFH treatment decreased the levels of circulating histones and alleviated intestinal microvascular endothelial injuries in endotoxemic rats. Furthermore, UFH inhibited histone cytotoxicity in vitro. CONCLUSIONS: UFH attenuated microcirculatory dysfunction in endotoxemic rats by antagonizing extracellular histones, thereby providing a potential therapeutic strategy for sepsis.

Roles of RAGE/ROCK1 Pathway in HMGB1-Induced Early Changes in Barrier Permeability of Human Pulmonary Microvascular Endothelial Cell.

Background: High mobility group box 1 (HMGB1) causes microvascular endothelial cell barrier dysfunction during acute lung injury (ALI) in sepsis, but the mechanisms have not been well understood. We studied the roles of RAGE and Rho kinase 1 (ROCK1) in HMGB1-induced human pulmonary endothelial barrier disruption. Methods: In the present study, the recombinant human high mobility group box 1 (rhHMGB1) was used to stimulate human pulmonary microvascular endothelial cells (HPMECs). The endothelial cell (EC) barrier permeability was examined by detecting FITC-dextran flux. CCK-8 assay was used to detect cell viability under rhHMGB1 treatments. The expression of related molecules involved in RhoA/ROCK1 pathway, phosphorylation of myosin light chain (MLC), F-actin, VE-cadherin and ZO-1 of different treated groups were measured by pull-down assay, western blot and immunofluorescence. Furthermore, we studied the effects of Rho kinase inhibitor (Y-27632), ROCK1/2 siRNA, RAGE-specific blocker (FPS-ZM1) and RAGE siRNA on endothelial barrier properties to elucidate the related mechanisms. Results: In the present study, we demonstrated that rhHMGB1 induced EC barrier hyperpermeability in a dose-dependent and time-dependent manner by measuring FITC-dextran flux, a reflection of the loss of EC barrier integrity. Moreover, rhHMGB1 induced a dose-dependent and time-dependent increases in paracellular gap formation accompanied by the development of stress fiber rearrangement and disruption of VE-cadherin and ZO-1, a phenotypic change related to increased endothelial contractility and endothelial barrier permeability. Using inhibitors and siRNAs directed against RAGE and ROCK1/2, we systematically determined that RAGE mediated the rhHMGB1-induced stress fiber reorganization via RhoA/ROCK1 signaling activation and the subsequent MLC phosphorylation in ECs. Conclusion: HMGB1 is capable of disrupting the endothelial barrier integrity. This study demonstrates that HMGB1 activates RhoA/ROCK1 pathway via RAGE, which phosphorylates MLC inducing stress fiber formation at short time, and HMGB1/RAGE reduces AJ/TJ expression at long term independently of RhoA/ROCK1 signaling pathway.

Rab14 Overexpression Promotes Proliferation and Invasion Through YAP Signaling in Non-Small Cell Lung Cancers.

INTRODUCTION: Several reports have shown that Rab14 is dysregulated in human cancers suggesting that it is an oncogenic protein closely related to tumorigenesis. However, whether Rab14 plays a role in the development and progression of human non-small cell lung cancer (NSCLC) remains unclear. METHODS: Rab14 protein levels were examined in 115 cases of NSCLC tissues and 6 cancer cell lines. Rab14 knockdown was performed in H1299 and A549 cell lines. Rab14 plasmid transfection was performed in the LK2 cell line. The biological roles and mechanisms of Rab14 were examined using MTT, colony formation, Matrigel invasion assay, migration assay, cell cycle analysis, Western blotting, and RT-qPCR. RESULTS: We found that Rab14 was upregulated in 65 of 115 lung cancer tissues. Rab14 high expression was significantly correlated with advanced TNM stage and nodal metastasis. Rab14 protein levels were higher in lung cancer cell lines than in normal bronchial cell line. Functionally, Rab14 overexpression increased growth rate, colony formation, invasion/migration ability and cell cycle progression, while Rab14 siRNA decreased the cell proliferation rate, colony numbers and inhibited invasion/migration ability and cell cycle progression. Rab14 upregulated cyclin D1, cyclin E, connective tissue growth factor (CTGF) and downregulated p27 protein and mRNA levels in both A549 and H1299 cell lines, while Rab14 siRNA produced the opposite effects. Further study showed that Rab14 overexpression increased luciferase reporter activity from transcriptional enhanced associate domain (TEAD) protein. Accordingly, Rab14 increased total Yes-associated protein (YAP) and nuclear YAP protein while decreased phosphorylated (p)-YAP and cytoplasmic YAP protein expression. Cycloheximide treatment showed that Rab14 downregulated the level of YAP degradation. Depletion of YAP using siRNA abolished the influence of Rab14 on cyclin D1, cyclin E, and CTGF. YAP knockdown also partly abolished the effects of Rab14 on cell proliferation and invasion. CONCLUSION: In summary, our data showed that Rab14 is overexpressed in human NSCLC. Rab14 facilitated proliferation and invasion, possibly through regulation of YAP signaling.

A study on depression of the elderly with different sleep quality in pension institutions in Northeastern China.

BACKGROUND: China owns he largest aged population in the world, and the elderly adults who live in pension institutions are more likely to suffer from mental disorders than other elderly adults. The purpose of this study is to discover the risky factors of depression among nursing home residents with various sleeping quality. METHODS: We conducted a cross-sectional study in Northeastern China from May to September in 2017 using multistage sampling method and 507 elderly people without cognitive impairment in six pension institutions were interviewed. The Pittsburgh Sleep Quality Index (PSQI) and Geriatric Depression Scale (GDS) were adopted to collect the information of sleep quality and depression. We used logistic regression to analyze the factors influencing depression among the elderly adults with poor or good sleep quality. RESULTS: The overall depression rate among elderly adults was 21.7%. The logistic regression analysis revealed that marital status, chronic disease, regular exercise, physical ache, filial piety and chewing ability had significant effects on the depression of the elderly with good sleep quality. Loneliness, self-caring ability, chewing ability and chronic diseases had significant effects on depression of the elderly with poor sleep quality. CONCLUSION: The prevalence of depressive symptoms in the elderly is not high. However, sleeping quality distinguishes root causes on elderly adults depression. Therefore, the risk factors of depression among elderly adults should be analyzed separately.

Risk of invasive candidiasis with prolonged duration of ICU stay: a systematic review and meta-analysis.

OBJECTIVE: This study aimed to evaluate the duration of intensive care unit (ICU) stay prior to onset of invasive candidiasis (IC)/candidaemia. DESIGN: Systematic review and meta-analysis. DATA SOURCES: PubMed, Cochrane, Embase and Web of Science databases were searched through June 2019 to identify relevant studies. ELIGIBILITY CRITERIA: Adult patients who had been admitted to the ICU and developed an IC infection. DATA EXTRACTION AND SYNTHESIS: The following data were extracted from each article: length of hospital stay, length of ICU stay, duration of ICU admission prior to candidaemia onset, percentage of patients who received antibiotics and duration of their antibiotic therapy prior to candidaemia onset, and overall mortality. In addition to the traditional meta-analyses, meta-regression was performed to explore possible mediators which might have contributed to the heterogeneity. RESULTS: The mean age of patients ranged from 28 to 76 years across selected studies. The pooled mean duration of ICU admission before onset of candidaemia was 12.9 days (95% CI 11.7 to 14.2). The pooled mean duration of hospital stay was 36.3±5.3 days (95% CI 25.8 to 46.7), and the pooled mean mortality rate was 49.3%±2.2% (95% CI 45.0% to 53.5%). There was no significant difference in duration of hospital stay (p=0.528) or overall mortality (p=0.111), but a significant difference was observed in the mean length of ICU stay (2.8 days, p<0.001), between patients with and without Candida albicans. Meta-regression analysis found that South American patients had longer duration of ICU admission prior to candidaemia onset than patients elsewhere, while those in Asia had the shortest duration. CONCLUSIONS: Patients with IC are associated with longer ICU stay, with the shortest duration of ICU admission prior to the candidaemia onset in Asia. This shows a more proactive strategy in the diagnosis of IC should be considered in caring for ICU patients.

[Effect of unfractionated heparin on high mobility group box 1-mediated expression of vascular endothelial cadherin].

OBJECTIVE: To observe the damage of high mobility group box 1 (HMGB1) on human umbilical vein endothelial cell (HUVEC) barrier permeability and the protective effect of unfractionated heparin (UFH), and to explore the down-regulated protection effect mechanism of UFH on HMGB1-mediated vascular endothelial cadherin (VE-cadherin) expression. METHODS: The trypsin-digested HUVEC were subcultured in culture flasks. When the cells were grown to 80%, they were randomly divided into four groups: phosphate buffer (PBS) control group (200 µL PBS), recombinant human high mobility group box 1 (rhHMGB1) treatment group (100 µg/L rhHMGB1), UFH control group (10 kU/L UFH), and UFH pretreatment group (10 kU/L UFH+100 µg/L rhHMGB1). The cells in each group were challenged with different reagent for 24 hours, and the activity of endothelial cells was determined by methyl thiazolyl tetrazolium (MTT) colorimetric assay. The permeability of endothelial cells was measured by Transwell method, and the expression and distribution of VE-cadherin was observed by immunofluorescence. The protein expressions of VE-cadherin and phosphorylated p38 mitogen-activated protein kinase (p-p38MAPK) were determined by Western Blot. RESULTS: After treatment with 100 µg/L rhHMGB1 for 24 hours, the activity of endothelial cells was not significantly different from that of the PBS control group (A value: 0.230±0.004 vs. 0.255±0.006, P > 0.05), but the permeability was significantly increased (glucan FD40 fluorescence intensity: 11.05±0.12 vs. 6.34±0.39, P < 0.05). Compared with PBS control group, the fluorescence microscopy showed that the VE-cadherin membrane localization was reduced, the distribution was loose, and there were obvious fissures between cells in rhHMGB1 treatment group, and quantitative analysis showed the protein expression of VE-cadherin was decreased significantly (VE-cadherin/ß-actin: 0.16±0.04 vs. 0.31±0.03, P < 0.05), and the expression of p-p38MAPK protein was significantly increased (p-p38MAPK/ß-actin: 0.79±0.03 vs. 0.26±0.05, P < 0.05). UFH pretreatment could protect HMGB1-mediated endothelial cell injury, cell permeability was significantly reduced (glucan FD40 fluorescence intensity: 9.11±0.23 vs. 11.05±0.12), fluorescence expression of VE-cadherin was enhanced, membrane localization was significantly increased, quantitative analysis showed that VE-cadherin protein expression was significantly up-regulated (VE-cadherin/ß-actin: 0.24±0.02 vs. 0.16±0.04), and p38MAPK phosphorylation level was significantly decreased (p-p38MAPK/ß-actin: 0.54±0.05 vs. 0.79±0.03), the difference was statistically significant as compared with rhHMGB1 treatment group (all P < 0.05). There was no significant difference in all parameters between PBS control group and UFH control group. CONCLUSIONS: UFH can protect the endothelial cell barrier from the HMGB1 by regulating the expression and distribution of VE-cadherin. The mechanism may be related to the inhibition of p38MAPK phosphorylation by UFH.

Unfractionated Heparin Alleviates Human Lung Endothelial Barrier Dysfunction Induced by High Mobility Group Box 1 Through Regulation of P38-GSK3ß-Snail Signaling Pathway.

BACKGROUND/AIMS: The high mobility group box 1 (HMGB1) has been regarded as an important inflammatory mediator. Previous studies showed the involvement of HMGB1 protein in the dysfunction of endothelial barrier function during acute lung injury. However, the molecular mechanism remains unclear. METHODS: In this study, we used recombinant human HMGB1 (rhHMGB1) and HMGB1 plasmid to treat human pulmonary microvascular endothelial cell (HPMECs). We examined endothelial permeability by measuring TEER value and HRP flux. Western blot and real-time PCR were used to examined change of endothelial-to-mesenchymal transition (EndoMT) markers and related pathways. Immunofluorescence was used to examine localization and expression of ZO-1 and VE-cadherin. SB203580.was used to block p38 pathway. Unfractionated heparin (UFH) and RAGE siRNA were also used to antagonize the effect of HMGB1. RESULTS: We showed that HMGB1 induced EndoMT with downregulation of ZO-1 and VE-cadherin at both mRNA and protein levels in HPMECs. We also demonstrated that HMGB1 upregulated endothelial permeability by measuring TEER value and HRP flux. Moreover, HMGB1 activated p38/GSK3ß/Snail signaling pathway and treatment with p38 inhibitor SB203580 abolished its biological effects. In addition, we found that UFH was able to reverse the effect of HMGB1 on EndoMT and endothelial permeability through inhibition of p38 signaling in a dose-dependent manner. We discovered that RAGE, a membrane receptor of HMGB1, transduced p38/Snail pathway to EndoMT. RAGE siRNA inhibited the effect of HMGB1 induced EndoMT in HPMECs. CONCLUSION: The present study demonstrated that HMGB1 induced EndoMT through RAGE receptor and p38/GSK3ß/Snail pathway. While UFH antagonized HMGB1 and maintained the integrity of the endothelial barrier through p38 inhibition.

[Effect of unfractionated heparin on the expression of heme oxygenase-1 in intestinal mucosa of mice with sepsis].

Objective: To investigate the effect of unfractionated heparin (UFH) on the expression of heme oxygenase-1 (HO-1) in intestinal mucosa of mice with sepsis. Methods: Thirty-six male C57BL/6J mice were randomly divided into sham group, cecal ligation and puncture (CLP) group and UHF group, n =12 in each group. Model of intestinal injury in sepsis was induced by CLP. In sham group, the mice were exposed without ligation of cecum. In UFH group, the mice were treated intravenously with 8 U of UFH via the tail vein half an hour before the operation and 12 hours after the surgery respectively. Six mice in each group were randomly chosen at 4 hours and 24 hours after operation to collect inferior vena venous blood samples and terminalileum tissues. The serum levels of interleukins (IL-1 ß,IL-6),and tumor necrosis factor-α (TNF-α) were determined by enzyme linked immunosorbent assay (ELISA).The serum level of D-lactate was determined by colorimetry.Pathological changes of ileum tissue and Chiu score were observed after hematoxylin eosin (HE) staining. The HO-1 expression was detected immunohistochemically. Results: In sham group, no significant changes in the serum levels of IL-1 ß,IL-6,TNF-α and D-lactate were observed. Twenty-four hours after the operation, the structure of intestinal mucosa was basically normal without obvious pathology change and no HO-1 positive cells were found. The serum levels of IL-1 ß,IL-6,TNF-α,and D-lactate in CLP group were gradually increased, and they were significantly increased as compared with sham group [IL-1 ß (ng/L):40.87±2.88 vs.22.60±2.05 at 4 hours,113.73±3.96 vs.22.07±2.74 at 24 hours;IL-6 (ng/L):63.89±3.26 vs.44.89±3.38 at 4 hours,176.56±5.45 vs.45.76±4.02 at 24 hours; TNF-α (ng/L):194.62± 14.13 vs.152.05±6.22 at 4 hours,599.62± 10.20 vs.155.90± 14.18 at 24 hours; D-lactate (mmol/L):0.24± 0.02 vs.0.19 ± 0.01 at 4 hours,0.33 ± 0.04 vs.0.20 ± 0.02 at 24 hours, all P ＜ 0.05].Twenty-four hours after the operation, edema and inflammation in ileal mucosa, intestinal villi structural damage were observed, the Chiu score was significantly higher than those in the sham group [4.5 (3.0-5.0) vs.0 (0-1.0),P ＜ 0.05],and a small amount of HO-1 positive cells were localized in the intestinal mucosa. Compared with CLP group, the serum levels of IL-1 ß,IL-6,TNF-α,and D-lactate of UFH group were significantly decreased [IL-1 ß (ng/L):31.53 ± 2.90 vs.40.87 ± 2.88 at 4 hours,61.13 ± 2.80 vs.113.73 ± 3.96 at 24 hours;IL-6 (ng/L):51.16 ± 5.68 vs.63.89 ± 3.26 at 4 hours,81.16 ± 4.54 vs.176.56 ± 5.45 at 24 hours; TNF-α (ng/L):171.76± 5.60 vs.194.62± 14.13 at 4 hours,328.48 ± 10.79 vs.599.62± 10.20 at 24 hours; D-lactate (mmol/L):0.21 ±0.01 vs.0.24±0.02 at 4 hours,0.24±0.02 vs.0.33±0.04 at 24 hours, all P ＜ 0.05]. Twenty-four hours after the operation, intestinal injury was ameliorated, the Chiu score was significantly lower [1.5 (1.0-5.0) vs.4.5 (3.0-5.0),P ＜ 0.05],and HO-1 positive cells in the intestinal mucosa was remarkably increased. Conclusion: UFH can enhance the expression of HO-1 in intestinal mucosa, reduce the release of inflammatory factors, ameliorate the intestinal inflammatory response, and thus play a protective role in intestinal tissue in mice with sepsis.

[shRNAs targeting high mobility group box-1 lead to inhibition of E-selectin expression via homeobox A9 in human umbilical vein endothelial cells].

OBJECTIVE: To approach the regulatory mechanism of high mobility group box-1 ( HMGB1 ) on the expression of E-selectin in human umbilical vein endothelial cell ( HUVEC ). METHODS: Homeobox A9 ( HOXA9 ) siRNA was transfected to HUVEC at logarithmic phase, real-time fluorescence quantitative polymerase chain reaction ( real-time qPCR ) and Western Blot were used to determine the HOXA9 mRNA expression and protein expressions; a blank control group and a nonsilence negative control group were set. HUVEC stable transfected with pRNA-u6.1/Neo-HMGB1 shRNA plasmids ( HUVEC with low-expression HMGB1 ) was obtained, and HOXA9 and E-selectin mRNA expressions were determined with real-time qPCR; a nonsilence transfection group served as the negative control. The HOXA9 siRNA was transfected to HUVEC with low-expression HMGB1 as co-transfection group, and the E-selectin expressions was determined with real-time qPCR; a HMGB1 shRNA group and a HOXA9 nonsilence group served as control. RESULTS: (1) HOXA9 mRNA ( 2(-Δ ΔCT) ) and protein expression ( integral A value ) in blank control group were 1.094±0.115 and 1.031±0.060. Compared with nonsilence transfection group, HOXA9 siRNA transfection group could significantly reduced mRNA and protein expression of HOXA9 [ HOXA9 mRNA ( 2(-Δ ΔCT) ): 0.257±0.030 vs. 1.035±0.091, t = 14.010, P = 0.002; HOXA9 protein ( integral A value ): 0.278±0.042 vs. 0.975±0.014, t = 27.310, P = 0.002 ]. (2) Compared with nonsilence transfection group, HMGB1 shRNA transfection could up-regulate HOXA9 mRNA expression in HUVEC ( 2(-Δ ΔCT) : 2.519±0.278 vs. 0.856±0.063, t = 10.100, P = 0.001 ), also could down-regulate E-selectin mRNA expression ( 0.311±0.046 vs. 1.080±0.201, t = 7.415, P = 0.000 ). (3) Compared with HOXA9 nonsilence group and HMGB1 shRNA group, HMGB1 shRNA and HOXA9 siRNA co-transfected HUVEC cells could significantly elevate E-selectin mRNA expression ( 2(-Δ ΔCT) : 3.445±0.428 vs. 1.085±0.212, 1.004±0.104, t(1) = 8.507, t(2) = 9.603, both P < 0.001 ). CONCLUSIONS: HMGB1 may regulate E-selectin expression through the HOXA9 regulation in HUVEC.

Downregulation of high mobility group box 1 attenuates the severity of acute lung injury in endotoxemic mice.

High mobility group box 1 (HMGB1) is a systemic inflammation­associated cytokine mediator. The aim of the present study was to examine the effect of the downregulation of HMGB1 in a lipopolysaccharide (LPS)­induced mouse model of acute lung injury (ALI). It was identified that serum levels of tumor necrosis factor­α and interleukin­1ß, lung myeloperoxidase activity and malondialdehyde content, as well as lung wet/dry weight ratios were all increased following LPS challenge. However, LPS­mediated increases in these parameters were significantly downregulated in HMGB1 small interfering (si)RNA­treated mice versus the negative control siRNA­treated mice. In addition, the administration of HMGB1 siRNA in LPS­treated mice resulted in a decreased DNA binding activity of nuclear factor­κB (NF­κB) in the lung. It was demonstrated that downregulation of HMGB1 decreases inflammation and the severity of sepsis associated with ALI, possibly via inhibiting the NF­κB DNA­binding activity. The present data support HMGB1 as a contributor to the pathogenesis of LPS­induced sepsis and ALI.

Treatment of low molecular weight heparin inhibits systemic inflammation and prevents endotoxin-induced acute lung injury in rats.

To determine whether low molecular weight heparin (LMWH) is able to reduce pulmonary inflammation and improve the survival in rats with endotoxin-induced acute lung injury (ALI). Rat ALI model was reproduced by injection of lipopolysaccharide (LPS) into tail vein. Rats were divided randomly into three groups: control group, ALI group, LMWH-treated group. Blood was collected and lung tissue was harvested at the designated time points for analysis. The lung specimens were harvested for morphological studies, streptavidin-peroxidase immunohistochemistry examination. Lung tissue edema was evaluated by tissue water content. The levels of lung tissue myeloperoxidase (MPO) were determined. Meanwhile, the nuclear factor-kappa B (NF-κB) activation, tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) levels and high mobility group box 1 (HMGB1) and intercellular adhesion molecule-1 (ICAM-1) protein levels in the lung were studied. In survival studies, a separate group of rats were treated with LMWH or sterile saline after LPS administration. Then, the mortality was recorded. Treatment with LMWH after ALI was associated with a reduction in the severity of LPS-induced lung injury. Treatment with LMWH significantly decreased the expression of TNF-α, IL-1ß, HMGB1 and ICAM-1 in the lung of ALI rats. Similarly, treatment with LMWH dramatically diminished LPS-induced neutrophil sequestration and markedly reduced the enhanced lung permeability. In the present study, LMWH administration inhibited the nuclear translocation of NF-κB in the lung. Survival was significantly higher among the LMWH-treated group compared with the ALI group. These data suggest that LMWH attenuates inflammation and prevents lethality in endotoxemic rats.

Downregulation of HMGB1 protects against the development of acute lung injury after severe acute pancreatitis.

OBJECTIVE: To examine the effect of downregulation of high mobility group box 1 (HMGB1) on severe acute pancreatitis (SAP) associated with acute lung injury (ALI), and its subsequent effect on disease severity. METHODS: Wistar rats were given an IV injection of pRNA-U6.1/Neo-HMGB1, pRNA-U6.1/Neo-vector or saline before induction of SAP. Then, SAP was induced in rats by the retrograde injection of 5% sodium taurocholate into the pancreatic duct. The control group received only a sham operation. Lung and pancreas samples were harvested after induction of SAP. The protein levels of HMGB1, matrix metalloproteinase-9 (MMP-9) and intercellular adhesion molecule-1 (ICAM-1) in lung tissue were investigated. The severity of pancreatic injury was determined by a histological score of pancreatic injury, serum amylase, and pancreatic water content. The lung injury was evaluated by measurement of pulmonary microvascular permeability, lung myeloperoxidase activity and malondialdehyde levels. RESULTS: The results found that in pRNA-U6.1/Neo-HMGB1 treated rats, serum tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) levels were decreased and the severity of pancreatic tissue injury was less compared with either untreated SAP or pRNA-U6.1/Neo-vector treated rats (P<0.05). The administration of pRNA-U6.1/Neo-HMGB1 in SAP-induced rats downregulated the DNA binding activity of the nuclear factor-kappa B (NF-κB) and the expressions of MMP-9 and ICAM-1 in lung. Thus, compared with the untreated SAP rats, the inflammatory response and the severity of ALI decreased (P<0.05). CONCLUSIONS: These results demonstrate that HMGB1 could augment Inflammation by inducing nuclear translocation of NF-κB, thus aggratating the severity of SAP associated with ALI.

shRNAs targeting high-mobility group box-1 inhibit E-selectin expression via homeobox A9 in human umbilical vein endothelial cells.

The nucleus of the endothelial cell contains large amounts of high-mobility group box protein 1 (HMGB1), a cytokine mediator of inflammation, and the endothelium may be a crucial source of HMGB1 during the inflammatory response. Therefore, the downregulation of HMGB1 expression by RNA interference (RNAi) may decrease inflammatory activity. The aim of this study was to investigate the possible mechanism of action and the effect of HMGB1 on homeobox A9 (HOXA9) and E-selectin expression. Recombinant human full-length HMGB1 was cloned by PCR amplification from human umbilical vein endothelial cells (HUVECs) and then subcloned into a pcDNA­3.1-myc-his-B vector. Specific short hairpin RNAs (shRNAs) for the HMGB1 target sequence and a scrambled sequence were designed, synthesized and cloned into a pRNA­U6.1/Neo vector. Specific small interfering RNAs (siRNAs) for the HOXA9 target sequence were commercially prepared and the expression levels of HMGB1, HOXA9, intracellular adhesion molecule 1 (ICAM1), vascular cell adhesion molecule 1 (VCAM1) and E-selectin were detected using real-time PCR and western blot analysis. The expression of the full-length HMGB1 gene and protein was verified in HUVECs. The shRNA for HMGB1 and siRNA for HOXA9 successfully decreased the expression levels of HMGB1 and HOXA9, respectively. ICAM1, VCAM1 and E-selectin were downregulated through HMGB1 interference in HUVECs, and HMGB1 shRNA decreased E-selectin expression by HOXA9. These results demonstrated the potential use of specific siRNA targeting HMGB1 expression for the development of novel therapeutic agents for inflammatory disorders.

Protective effect of ethyl pyruvate on pancreas injury in rats with severe acute pancreatitis.

BACKGROUND: Systemic inflammatory mediators have an important role in the development of acute pancreatitis. In this study, we investigated the effect of ethyl pyruvate (EP) on pancreas injury in rats with severe acute pancreatitis (SAP) and its possible mechanism. METHODS: We randomly allocated rats into the following three experimental groups: control and SAP- and EP-treated. Then, we recorded the mortality rate. We harvested tissue specimens for morphological studies, streptavidin-peroxidase immunohistochemistry examination, and Western blot analysis. We tested the levels of pancreatic tissue malondialdehyde and the activity of serum amylase, myeloperoxidase in the pancreas. In addition, we studied nuclear factor-κB (NF-κB) activation, tumor necrosis factor-α levels, and high mobility group box 1 protein expression levels in the pancreas. RESULTS: Treatment with EP after SAP was associated with a reduction in the severity of SAP and pancreas injury. Treatment with EP significantly decreased the expression of tumor necrosis factor-α and high mobility group box 1, and ameliorated malondialdehyde concentration and myeloperoxidase activity in the pancreas in SAP rats. Compared with the SAP group, treatment with EP significantly decreased the number of inflammatory cell infiltration, markedly inhibited pancreatic NF-κB DNA binding, and increased the survival rates. CONCLUSIONS: This study demonstrates that preventing the activation of NF-κB by EP ameliorates tissue injury associated with experimental murine acute pancreatitis. This result provides an important insight into the molecular biology of acute pancreatitis.

[Effect of down-regulation of high mobility group box-1 expression on proliferation and migration abilities of human umbilical vein endothelial cells].

OBJECTIVE: To investigate the effect of down-regulation of high mobility group box-1 (HMGB1) expression on the proliferation and migration abilities of human umbilical vein endothelial cell ( HUVEC) in vitro. METHODS: The method of stable transfection was used to transfect the pRNA-u6.1/Neo-control and pRNA-u6.1/ Neo-HMGB1 short hairpin RNA (shRNA) plasmid to HUVEC cells, and control and HMGB1 shRNA cell lines were reproduced, and the cells were identified by Western blotting test and real-time fluorescence reverse transcription-polymerase chain reaction (RT-PCR). Then methyl thiazolyl tetrazolium (MTT) was used for the determination of the proliferative ability, flow cytometry was used for determining the changes in cell cycle distribution ability of HUVEC, and the migratory ability was detected by scratch test. RESULTS: Western blotting and RT -PCR detection proved the production of stable transfection cell lines was successful, and the content of HMGB1 protein and mRNA expression in cells were significantly lower after cultivation for 72 hours than those of control cells (protein: 0.436 ± 0.027 vs. 1.017 ± 0.038, I= 12.180, P=0.000; mRNA: 0.436 ± 0.031 vs. 1.020 ± 0.051, T=9.660, P= 0.001 ). The results of MTT showed that the proliferation ability of HMGB1 shRNA cell lines was lower obviously 2, 3, 4, 5 days after transfection than that of control cells ( 2 days: 0.210 ± 0.023 vs. 0.240 ± 0.011, T= 1.050, P=0.351; 3 days: 0.240 ± 0.022 vs. 0.361 ± 0.030, T=3.203, P=0.033; 4 days: 0.373 ± 0.031 vs. 0.531 ± 0.033, T=3.530, P=0.022; 5 days: 0.441 ± 0.031 vs. 0.602 ± 0.030, T=4.180, P=0.106). Flow cytometry results showed that the number of HMGB 1 shRNA cells in S phase was significantly lower than that of the control cell line ( ( 13.10 ± 1.10 )% vs. (21.12 ± 1.20)%, T=4.950, P=0.001). Scratch test showed that the healing ability of HMGB1 shRNA cell line was lowered significantly at 12 hours as compared with that of control ( (20.17 ± 3.33 )% vs. ( 88.53 ± 3.15 )% , T= 14.142, P=0.000). CONCLUSION: HMGB 1 shRNA can significantly inhibit HUVEC cell proliferation and migration.

[Construction of stable human umbilical vein endothelial cells line expressing short hairpin RNA (shRNA) targeting high mobility group box-1 gene].

OBJECTIVE: To construct the short hairpin RNA (shRNA) targeting high mobility group box-1 (HMGB1) and culture the stable human umbilical vein endothelial cell (HUVEC) line expressing this shRNA. METHODS: Based on the HMGB1 gene sequence, shRNA was designed, synthesized and subcloned into the pRNA-u6.1/Neo vector, while negative controls were also established. Then the recombinant vector was transfected into HUVEC cell line and the cell was screened with G418 and assayed by using real time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. RESULTS: Restriction endonuclease digestion test and sequencing verification showed that the recombinant pRNA-u6.1/Neo vector expressing this shRNA targeting HMGB1 was successfully constructed and the stable HUVEC cell line expressing this shRNA was developed. The real time RT-PCR and Western blotting was used to detect that recombinant plasmid in HUVEC cell effect on expression of HMGB1 was reduced. (mRNA: 0.4635 ± 0.0342 vs. 1.0340 ± 0.0352, protein: 0.4510 ± 0.0200 vs. 1.0210 ± 0.0110, both P<0.05). CONCLUSION: The recombinant pRNA-u6.1/Neo vector expressing shRNA targeting HMGB1 was successfully constructed and the stable HUVEC cell line expressing this shRNA was developed, and therefore allowed further investigation regarding the function of HMGB1 gene in the HUVEC cell line.

Therapeutic treatment with ethyl pyruvate attenuates the severity of liver injury in rats with severe acute pancreatitis.

OBJECTIVE: The objective of the study was to evaluate the effect of ethyl pyruvate (EP) in ameliorating liver injury in rats with severe acute pancreatitis (SAP) and its possible mechanism. METHODS: Rats were randomly divided into control group, SAP group, and EP-treated group. Then, the tissue specimens were harvested for morphological studies, immunohistochemistry examination, reverse transcriptase-polymerase chain reaction, and Western blot analysis. The DNA-binding activity of nuclear factor κB was measured by electrophoretic mobility shift assay. The concentrations of serum amylase, alanine aminotransferase, and pancreatic tissue malondialdehyde and the activity of myeloperoxidase in the liver were determined. RESULTS: Treatment with EP after SAP was associated with a reduction in the severity of SAP and liver injury. Treatment with EP significantly decreased the hepatic mRNA expression of tumor necrosis factor α and interleukin 1ß and ameliorated the activity of myeloperoxidase in the liver in SAP rats. Compared with the SAP group, treatment with EP significantly decreased the infiltration of inflammatory cells and markedly inhibited hepatic nuclear factor κB DNA binding; EP therapy dramatically inhibited high-mobility group box 1 expression from inflamed hepatic tissue. CONCLUSIONS: Our results demonstrate that EP might play a therapeutic role in liver inflammation in this SAP model, and these beneficial effects of EP are because of the modulation of high-mobility group box 1 and other inflammatory cytokine responses.

HMGB1 activates nuclear factor-κB signaling by RAGE and increases the production of TNF-α in human umbilical vein endothelial cells.

OBJECTIVE: High mobility group box chromosomal protein 1 (HMGB1) is a lately discovered candidate molecule identified as an important extracellular mediator in systemic inflammation. Systemic inflammation results in endothelial cell activation and microvascular injury. In the present study, we investigated the effects of HMGB1 on the activation of human umbilical vein endothelial cells (HUVECs) and defined pathways activated by HMGB1. METHODS: HUVECs obtained by collagenase treatment of umbilical cord veins were stimulated in vitro with HMGB1. The activation of HUVECs was studied regarding (i) the kinetics of tumor necrosis factor-α (TNF-α) production in HUVECs, (ii) HMGB1-induced up-regulation of receptor for advanced glycation end products (RAGE), (iii) HMGB1-induced nuclear translocation of nuclear factor kappa B (NF-κB) in HUVECs, (iv) the activation of signalling transduction pathways. RESULTS: HUVECs activation was stimulated by HMGB1 partially in a RAGE-dependent manner. Additionally, the HMGB1-induced activation of HUVECs was significantly inhibited by anti-RAGE monoclonal antibody and Ethyl pyruvate (EP) that had been shown to be an effective anti-inflammatory agent. Short-term prestimulation of HUVECs with HMGB1 caused a time-dependent increase in the secretion of TNF-α and expression of RAGE. Furthermore, HMGB1 stimulation resulted in nuclear translocation of transcription factor NF-κB. Most importantly, pretreatment with anti-RAGE monoclonal antibody significantly decreased the amounts of TNF-α and inhibited the nuclear translocation of NF-κB. Additionally in HUVECs cultures, EP specifically inhibited activation of NF-κB signaling pathway that are critical for TNF-α release. CONCLUSIONS: In conclusion, Our data present a link between HMGB1and RAGE function of endothelial cells and demonstrate the pathway activated by HMGB1. These findings may provide a novel therapeutic strategy to improve the endothelial cells function.

Role of high-mobility group box 1 protein in the pathogenesis of intestinal barrier injury in rats with severe acute pancreatitis.

OBJECTIVE: To investigate the role of high-mobility group box 1 (HMGB1) in the development of intestinal barrier injury of severe acute pancreatitis (SAP) and to examine the effect of ethyl pyruvate (EP) on intestinal inflammation in rats with SAP. METHODS: Rats were randomly divided into the following experimental groups: control, SAP, and EP treated. Then, the distal ileum was harvested for morphological studies, streptavidin-peroxidase immunohistochemistry examination, and Western blot analysis. The concentrations of plasma amylase, endotoxin, and diamine oxidase (DAO) and the activity of myeloperoxidase (MPO) in the intestine were determined. RESULTS: We found that the expression of HMGB1 was up-regulated in the ileal mucosa within 6 hours and then remained elevated for more than 48 hours after SAP. Meanwhile, the levels of plasma amylase, endotoxin, and DAO and the activity of MPO in the intestinal mucosa were rapidly increased after SAP. Whereas treatment with EP significantly decreased the expression of intestinal HMGB1, the levels of plasma amylase, endotoxin, and DAO ameliorated the activity of MPO in the intestine in SAP rats. CONCLUSIONS: Our results demonstrate that HMGB1 participates in intestinal barrier injury in SAP and EP might play a therapeutic role in intestinal inflammation in this SAP model.