HSF1 Alleviates Brain Injury by Inhibiting NLRP3-Induced Pyroptosis in a Sepsis Model.

Background: Sepsis, which could cause a systemic inflammatory response, is a life-threatening disease with a high morbidity and mortality rate. There is evidence that brain injury may be related to severe systemic infection induced by sepsis. The brain injury caused by sepsis could increase the risk of mortality in septic patients, which seriously affects the septic patient's prognosis of survival. Although there remains a focus on sepsis research, clinical measures to prevent and treat brain injury in sepsis are not yet available, and the high mortality rate is still a big health burden. Therefore, it is necessary to investigate the new molecules or regulated pathways that can effectively inhibit the progress of sepsis. Objective: NLR family pyrin domain-containing 3 (NLRP3) increased in the procession of sepsis and functioned as the key regulator of pyroptosis. Heat shock factor 1 (HSF1) can protect organs from multiorgan dysfunction syndrome induced by lipopolysaccharides in mice, and NLRP3 could be inhibited by HSF1 in many organs. However, whether HSF1 regulated NLRP3 in sepsis-induced brain injury, as well as the detailed mechanism of HSF1 in brain injury, remains unknown in the sepsis model. In this research, we try to explore the relationship between HSF1 and NLRP3 in a sepsis model and try to reveal the mechanism of HSF1 inhibiting the process of brain injury. Methods: In this study, we used wild-type mice and hsf1 -/- mice for in vivo research and PC12 cells for in vitro research. Real-time PCR and Western blot were used to analyze the expression of HSF1, NLRP3, cytokines, and pyrolytic proteins. EthD-III staining was chosen to detect the pyroptosis of the hippocampus and PC12 cells. Results: The results showed that HSF1 is negatively related to pyroptosis. The pyroptosis in cells of brain tissue was significantly increased in the hsf1 -/- mouse model compared to hsf1 +/+ mice. In PC12 cells, hsf1 siRNA can upregulate pyroptosis while HSF1-transfected plasmid could inhibit the pyroptosis. HSF1 could negatively regulate the NLRP3 pathway in PC12 cells, while hsf1 siRNA enhanced the pyroptosis in PC12 cells, which could be reversed by nlrp3 siRNA. Conclusion: These results imply that HSF1 could alleviate sepsis-induced brain injury by inhibiting pyroptosis through the NLRP3-dependent pathway in brain tissue and PC12 cells, suggesting HSF1 as a potential molecular target for treating brain injury in sepsis clinical studies.

Clopidogrel reduces lipopolysaccharide-induced inflammation and neutrophil-platelet aggregates in an experimental endotoxemic model.

Platelet activation contributes to organs failure in inflammation and plays an important role in endotoxemia. Clopidogrel inhibits platelet aggregation and activation. However, the role of clopidogrel in modulating inflammatory progression of endotoxemia remains largely unexplored. Therefore, we investigated the role of clopidogrel on the activation of platelet and leukocytes in lipopolysaccharide (LPS)-induced inflammation in mice. Animals were treated with clopidogrel or vehicle before LPS induction. The expression of neutrophil-platelet aggregates and platelet activation and tissue factor was determined. Immunofluorescence was used to analyze platelet-leukocyte interactions and tissue factor (TF) expression on leukocytes. Clopidogrel pretreatment markedly decreased lung damage, inhibited platelet-neutrophil aggregates and TF expression. In addition, clopidogrel reduced thrombocytopenia and affected the number of circulating white blood cell in endotoxemia mice. Moreover, clopidogrel also reduced platelet shedding of CD40L and CD62P in endotoxemic mice. Taken together, clopidogrel played an important role through reducing platelet activation and inflammatory process in endotoxemia.

Ginsenoside Rg1 Regulates SIRT1 to Ameliorate Sepsis-Induced Lung Inflammation and Injury via Inhibiting Endoplasmic Reticulum Stress and Inflammation.

OBJECTIVES: To investigate the protective effect of ginsenoside Rg1 on relieving sepsis-induced lung inflammation and injury in vivo and in vitro. METHODS: Cultured human pulmonary epithelial cell line A549 was challenged with LPS to induce cell injury, and CLP mouse model was generated to mimic clinical condition of systemic sepsis. Rg1 was applied to cells or animals at indicated dosage. Apoptosis of cultured cells was quantified by flow cytometry, along with ELISA for inflammatory cytokines in supernatant. For septic mice, lung tissue pathology was examined, plus ELISA assay for serum cytokines. Western blotting was used to examine the activation of inflammatory pathways and ER stress marker proteins in both cells and mouse lung tissues. Reactive oxygen species (ROS) level was quantified by DCFDA kit. RESULTS: Ginsenoside Rg1 treatment remarkably suppressed apoptosis rate of LPS-induced A549 cells, relieved mouse lung tissue damage, and elevated survival rate. Rg1 treatment also rescued cells from LPS-induced intracellular ROS. In both A549 cells and mouse lung tissues, further study showed that Rg1 perfusion significantly suppressed the secretion of inflammatory cytokines including tumor necrosis factor- (TNF-) alpha and interleukin- (IL-) 6 and relieved cells from ER stress as supported by decreased expression of marker proteins via upregulating sirtuin 1 (SIRT1). CONCLUSION: Our results showed that ginsenoside Rg1 treatment effectively relieved sepsis-induced lung injury in vitro and in vivo, mainly via upregulating SIRT1 to relieve ER stress and inflammation. These findings provide new insights for unrevealing potential candidate for severe sepsis accompanied with lung injury.

The Effects of Resveratrol on Inflammation and Oxidative Stress in a Rat Model of Chronic Obstructive Pulmonary Disease.

Oxidative stress and inflammation are hypothesized to contribute to the pathogenesis of chronic obstructive pulmonary disease (COPD). Resveratrol (trans-3,5,4'-trihydroxystilbene) is known for its antioxidant and anti-inflammatory properties. The study aimed to investigate the effects of resveratrol in a rat model with COPD on the regulation of oxidative stress and inflammation via the activation of Sirtuin1 (SIRTl) and proliferator-activated receptor-γ coactivator-1α (PGC-1α). Thirty Wistar rats were randomly divided into three groups: control group, COPD group and resveratrol intervention group. The COPD model was established by instilling with lipopolysaccharide (LPS) and challenging with cigarette smoke (CS). The levels of interleukin-6 (IL-6) and interleukin-8 (IL-8) in serum were measured. The levels of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were measured. The expression levels of SIRT1 and PGC-1α in the lung tissues were examined by immunohistochemistry as well as real-time reverse transcriptase polymerase chain reaction (real-time RT-PCR) and western blotting analysis. After the treatment with resveratrol (50 mg/kg), compared with the COPD group, alleviation of inflammation and reconstruction in the small airways of the lungs were seen. Resveratrol might be correlated not only with the lower level of MDA and the higher activity of SOD, but also with the upregulation of SIRT1 and PGC-1α expression. Resveratrol treatment decreased serum levels of IL-6 and IL-8. Our findings indicate that resveratrol had a therapeutic effect in our rat COPD model, which is related to the inhibition of oxidative stress and inflammatory response. The mechanism may be related to the activation and upgrading of the SIRT1/PGC-1α signaling pathways. Thus resveratrol might be a therapeutic modality in COPD.

Nicorandil alleviates cardiac remodeling and dysfunction post -infarction by up-regulating the nucleolin/autophagy axis.

OBJECTIVE: The present study aimed to investigate whether the drug nicorandil can improve cardiac remodeling after myocardial infarction (MI) and the underlying mechanisms. METHODS: Mouse MI was established by the ligation of the left anterior descending coronary artery and H9C2 cells were cultured to investigate the underlying molecular mechanisms. The degree of myocardial collagen (Col) deposition was evaluated by Masson's staining. The expressions of nucleolin, autophagy and myocardial remodeling-associated genes were measured by Western blotting, qPCR, and immunofluorescence. The apoptosis of myocardial tissue cells and H9C2 cells were detected by TUNEL staining and flow cytometry, respectively. Autophagosomes were observed by transmission electron microscopy. RESULTS: Treatment with nicorandil mitigated left ventricular enlargement, improved the capacity of myocardial diastolic-contractility, decreased cardiomyocyte apoptosis, and inhibited myocardial fibrosis development post-MI. Nicorandil up-regulated the expression of nucleolin, promoted autophagic flux, and decreased the expressions of TGF-ß1 and phosphorylated Smad2/3, while enhanced the expression of BMP-7 and phosphorylated Smad1 in myocardium. Nicorandil decreased apoptosis and promoted autophagic flux in H2O2-treated H9C2 cells. Autophagy inhibitors 3-methyladenine (3MA) and chloroquine diphosphate salt (CDS) alleviated the effects of nicorandil on apoptosis. Knockdown of nucleolin decreased the effects of nicorandil on apoptosis and nicorandil-promoted autophagic flux of cardiomyocytes treated with H2O2. CONCLUSIONS: Treatment with nicorandil alleviated myocardial remodeling post-MI through up-regulating the expression of nucleolin, and subsequently promoting autophagy, followed by regulating TGF-ß/Smad signaling pathway.

Shikonin Ameliorates LPS-Induced Cardiac Dysfunction by SIRT1-Dependent Inhibition of NLRP3 Inflammasome.

Shikonin (SHI) is an anti-inflammatory agent extracted from natural herbs. It is still unknown whether SHI ameliorates lipopolysaccharide (LPS)-induced cardiac dysfunction. This study aims to explore the protective effects of SHI on LPS-induced myocardial injury and its mechanism. The LPS-induced cardiac dysfunction mouse model was employed to investigate the protective effects of SHI. In the present study, we found that SHI treatment improved the survival rate and cardiac function and remarkably ameliorated the release of inflammatory cytokines and macrophage infiltration in heart tissue of LPS-treated mice. SHI also reduced lactate dehydrogenase (LDH) and cardiac troponin (cTn) release, cell inflammation, and apoptosis in LPS plus adenosine triphosphate (ATP)-treated H9c2 cells. In addition, SHI significantly upregulated silent information regulator 1 (SIRT1) expression and suppressed the upregulation of NOD-like receptor protein 3 (NLRP3), cleaved caspase-1, and caspase-1 activity in heart tissues induced by LPS. Meanwhile, we got the same results in LPS plus ATP-treated H9c2 cells in vitro. Further, SIRT1 inhibitor or siRNA partially blocked SHI-mediated upregulation of SIRT1 expression and downregulation of NLRP3, cleaved caspase-1, and caspase-1 activity in heart tissues induced by LPS. Therefore, we conclude that SHI ameliorates LPS-induced cardiac dysfunction by inhibiting SIRT1-dependent activation of NLRP3 inflammasomes and might be a promising therapeutic strategy for the treatment of LPS-induced cardiac dysfunction.

The role of PSGL-1 in pathogenesis of systemic inflammatory response and coagulopathy in endotoxemic mice.

INTRODUCTION: Endotoxemia often results in systemic inflammatory response syndrome (SIRS), coagulation disturbance and acute lung injury (ALI), and such a condition is associated with the activation of platelets, leukocytes and vascular endothelial cells (VECs). P-selectin glycoprotein ligand 1 (PSGL-1) is a key regulatory molecule in the activation of platelets, leukocytes and VECs. However, it still remains largely unexplored whether PSGL-1 plays an important role in SIRS, coagulation dysfunction and ALI of endotoxemia. In the present study, we aimed to study the role of PSGL-1 in above-mentioned situations using endotoxemic mice. MATERIALS AND METHODS: An endotoxemia model was established in BALB/c mice via lipopolysaccharide (LPS) administration. Moreover, the mice were simultaneously injected with PSGL-1 antibody for intervention. The survival rate, morphologic changes of lung tissues, platelet-leukocyte adhesion, tissue factor expression on leukocytes, fibrinogen deposition in lung tissues, serum levels of inflammatory factors and the activation of VECs were determined. RESULTS: The results showed that the aggregation and recruitment of platelets and leukocytes in lung tissues, the expression of tissue factor on leukocytes, the serum levels of inflammatory factors, the activation of VECs, and the fibrinogen deposition in lung tissues were increased in endotoxemic mice, which were significantly alleviated by administration of PSGL-1 antibody. Moreover, blockade of PSGL-1 markedly increased survival rate, and alleviated coagulation disturbance and lung injury in endotoxemic mice. CONCLUSIONS: Taken together, PSGL-1 played an important role in pathogenesis of SIRS and coagulation dysfunction and ALI in endotoxemic mice.

[The plasmic translocation and release of high mobility group box chromosomal protein 1 in peripheral blood monocytes of patients with rheumatoid arthritis and the effect of thalidomide].

OBJECTIVE: To investigate the release and intracellular localization of high mobility group box chromosomal protein 1 (HMGB1) in the peripheral blood monocytes of rheumatoid arthritis (RA) patients and the inhibitive effect of thalidomide. METHODS: 19 RA patients and 20 healthy controls were included in the study. Monocytes were separated from peripheral blood with Ficoll density gradient centrifugation. Monocytes were treated with 100 ng/ml tumor necrosis factor alpha (TNFalpha) or 100 ng/ml TNFalpha plus 40 microg/ml thalidomide and grown in an incubator at 37 degrees C with 5% CO2 for 24 hours. The culture supernatants of the monocytes were collected. HMGB1 level in the culture medium was detected with Western blot. In addition, the intracellular localization of HMGB1 in the monocytes was investigated with immunocytochemical analysis. RESULTS: Without stimulation, the release of HMGB1 protein was significantly increased in the culture supernatants of peripheral blood monocytes from RA patients as compared with that from healthy controls (P < 0.05). TNFalpha (100 ng/ml) did not further increase the release of HMGB1 in the monocytes from the patients with RA. Thalidomide (40 microg/ml) could inhibit the release of HMGB1 in the monocytes from RA patients stimulated with TNFalpha (P < 0.05). In the monocytes from RA patients, HMGB1 was mainly localized in the nucleus. Treatment with TNFalpha (100 ng/ml) for 24 hours resulted in a cytoplasmic translocation of HMGB1, which was inhibited significantly by thalidomide. CONCLUSION: TNFalpha induces the release and cytoplasmic translocation of HMGB1 in the peripheral blood monocytes of RA patients and thalidomide inhibits the release and translocation of HMGB1.

[Role of cell-surface nucleolin in lipopolysaccharide-stimulated expression and secretion of TNF-alpha and IL-1beta].

OBJECTIVE: To explore the role of cell-surface nucleolin in lipopolysaccharide (LPS)-stimulated expression and secretion of TNF-alpha and IL-1beta in human THP-1 monocytes. METHODS: Immuno-fluorescence assay and Western blot were used to identify the expression of nucleolin on the surface of THP-1 monocytes. Inactivation of nucleolin was induced by anti-nucleolin monoclonal antibody blockage, and the expression and secretion of TNF-alpha and IL-1beta were observed by using reverse transcription polymerase chain reaction (RT-PCR) and enzyme linked immuno-sorbent assay (ELISA)respectively in LPS-mediated human THP-1 monocyte inflammatory model. RESULTS: Immuno-fluorescence showed that nucleolin was localized on the cell surface of THP-1 monocytes as indicated by dotted red fluorescence. Western blot assay indicated that nucleolin existed in the cell membrane fractions. RT-PCR assay showed that the expressions of TNF-alpha and IL-1beta mRNA significantly increased at 2 h and 3 h after the treatment with 1000 microg/L LPS. After 1 h pretreatment with anti-nucleolin antibody, the levels of TNF-alpha and IL-1beta mRNA decreased compared with an anti-nucleolin antibody untreated group and an irrelevant IgG+LPS group (P<0.05). ELISA assay showed that the pretreatment with anti-nucleolin antibody inhibited significantly the secretion of LPS-induced levels of TNF-alpha and IL-1beta after 4, 12 and 24 h treatment with 1000 microg/L LPS. CONCLUSION: Nucleolin expresses on the cell surface of THP-1 monocytes and involves in the LPS-mediated expression and secretion of TNF-alpha and IL-1beta.

The CD40 rs1883832 Polymorphism Affects Sepsis Susceptibility and sCD40L Levels.

Sepsis is a severe and progressive disease characterized by systemic inflammatory response syndrome (SIRS). CD40 serves as a vital link between immune response and inflammation. This study was designed to investigate the potential association between a functional single-nucleotide polymorphism (SNP) of CD40 (rs1883832) and susceptibility to sepsis. We first performed a case-control study to explore the relationship between the CD40 rs1883832 polymorphism and sepsis. CD40 mRNA expression and protein expression were determined by real-time PCR and western blotting, respectively, in peripheral blood mononuclear cells (PBMCs) from sepsis patients and healthy controls. The plasma sCD40L levels in the two groups were measured by ELISA. The results showed that the frequencies of the TT genotype and the CD40 rs1883832 T allele were significantly higher in sepsis patients than in healthy controls. Plasma sCD40L levels were also significantly increased in sepsis patients. In addition, TT genotype carriers among sepsis patients displayed the highest CD40 expression at both the mRNA and protein levels, accompanied by the highest plasma sCD40L concentrations. In conclusion, the CD40 rs1883832 T allele acts as a risk factor for increased susceptibility to sepsis and may be involved in the process of sepsis through regulation of CD40 expression and plasma sCD40L levels.

MicroRNA Profiling of Transgenic Mice with Myocardial Overexpression of Nucleolin.

BACKGROUND: Nucleolin (NCL) is the most abundant RNA-binding protein in the cell nucleolus and plays an important role in chromatin stability, ribosome assembly, ribosomal RNA maturation, ribosomal DNA transcription, nucleocytoplasmic transport, and regulation of RNA stability and translation efficiency. In addition to its anti-apoptotic properties, the underlying mechanisms associated with NCL-related roles in different cellular processes remain unclear. In this study, the effect of NCL on microRNA (miRNA) expression was evaluated by generating transgenic mice with myocardial overexpression of NCL and by analyzing microarrays of mature and precursor miRNAs from mice. METHODS: Using microinjection of alpha-MyHc clone 26-NCL plasmids, we generated transgenic mice with myocardial overexpression of NCL firstly, and then mature and precursor miRNAs expression profiles were analyzed in NCL transgenic mice (n = 3) and wild-type (WT) mice (n = 3) by miRNA microarrays. Statistical Package for the Social Sciences version 16.0 software (SPSS, Inc., Chicago, IL, USA) was used to perform Student's t-test, and statistical significance was determined at P < 0.05. RESULTS: Several miRNAs were found to be differentially expressed, of which 11 were upregulated and 4 were downregulated in transgenic mice with myocardial overexpression of NCL compared to those in WT mice. Several differentially expressed miRNAs were subsequently confirmed and quantified by real-time quantitative reverse transcription-polymerase chain reaction. Bioinformatics analysis was used for the prediction of miRNA targets. Furthermore, in vitro experiments showed that NCL regulated miR-21 expression following hydrogen peroxide preconditioning. CONCLUSIONS: Myocardial-protection mechanisms exerted by NCL might be mediated by the miRNAs identified in this study.

Puerarin prevents vascular endothelial injury through suppression of NF-κB activation in LPS-challenged human umbilical vein endothelial cells.

OBJECTIVE: In the present study, we aimed to explore the effects of puerarin on vascular endothelial cell injury induced by lipopolysaccharide (LPS) and its underlying mechanisms. METHODS: The cell viability and morphological changes were assessed using the cell counting kit-8 (CCK-8) assay and 4´,6-diamidino-2-phenylindole (DAPI) staining, respectively. The levels of tumor necrosis factor-alpha (TNF-α), interleukin-1ß (IL-1ß), monocyte/macrophage chemotactic protein-1 (MCP-1), IL-8, intercellular cell adhesion molecule-1 (ICAM-1), thrombomodulin (TM) and plasminogen activator inhibitor-1 (PAI-1) in cell culture supernatant were determined by the enzyme-linked immunosorbent assay (ELISA). The neutrophils adhesion to endothelial cells were examined by myeloperoxidase activity assay. The nuclear translocation of nuclear factor-κB p65 (NF-κB p65) was assessed by immunofluorescence analysis. RESULTS: Compared with the control group, LPS challenge significantly injured human umbilical vein endothelial cells (HUVECs) and increased the levels of TNF-α, IL-1ß, MCP-1, IL-8, ICAM-1, TM and PAI-1 in the cell culture supernatants. The neutrophils adhesion to endothelial cells were significantly increased in LPS-challenged HUVECs. Moreover, LPS challenge increased the nuclear translocation of NF-κB p65. However, puerarin pre-treatment attenuated the vascular endothelial injury and reduced the levels of TNF-α, IL-1ß, MCP-1, IL-8, ICAM-1, TM and PAI-1 in cell supernatants of LPS-challenged HUVECs. In addition, the neutrophils adhesion to HUVECs induced by LPS were also decreased by puerarin pre-treatment. Furthermore, puerarin pre-treatment reduced the nuclear translocation of NF-κB p65 elicited by LPS. CONCLUSIONS: Puerarin prevented LPS-induced vascular endothelial injury, the mechanism of which might be related to the suppression of NF-κB activation and subsequently altered levels of inflammatory factors and coagulation-related factors.

[Endogenous myocardial protection: present questions and prospects].

Since the findings of Murry and Currie et al. that ischemic preconditioning (IPC) and heat shock response (HSR) could protect evidently myocardium against ischemia-reperfusion injury in the middle of 1980s, endogenous myocardial protection has drawn widespread attentions. A great quantity of studies completed during the past 25 years made much progress in endogenous myocardial protection. Abundant research experiences have been accumulated and a basic theoretical framework has been established in this field. However, there are still many questions need to be solved. In this review, we focused on clarifying some hot questions and important future directions in IPC, heat shock proteins (HSPs), research models and strategies in endogenous myocardial protection.

[Expression of high mobility group box chromosomal protein 1 in peripheral blood of patients with rheumatoid arthritis].

OBJECTIVE: To investigate the mRNA and protein expression of high mobility group box chromosomal protein 1 (HMGB1) in peripheral blood mononuclear cells (PBMCs) and serum. METHODS: Levels of HMGB1mRNA were detected with reverse transcription polymerase chain reaction (RT-PCR) in PBMC and levels of HMGB1 protein in PBMC and plasm were measured with Western blot in 38 patients with active rheumatoid arthritis (RA), 24 with inactive RA and 20 healthy controls. Ficoll density gradient centrifugation was used to separate PBMCs from peripheral blood. The correlation between the levels of HMGB1 in serum and the index of disease activity in RA was analyzed. RESULTS: There was no statistically significant difference of the mRNA expression of HMGB1 in PBMCs from active RA patients as compared with those from inactive RA group and healthy controls (F = 1.23, P > 0.05). The protein expression of HMGB1 was significantly lower in PBMCs from active RA patients (F = 70.91, P < 0.01), while the protein expression of HMGB1 was higher in plasma from active RA patients (P < 0.001) as compared with that from inactive RA patients and healthy controls. However, there was no statistically significant difference between inactive RA patients and healthy controls (P > 0.05). The level of HMGB1 protein in plasma of RA patients was correlated with erythrocyte sedimentation rate (ESR) (r(s) = 0.478, P < 0.001) and C- reactive protein (CRP) (r(s) = 0.574, P < 0.05). It was not correlated with age, the number of tender joints and swollen joints, radiographic scores and therapeutic effect. CONCLUSION: The protein expression of HMGB1 was significantly decreased in PBMCs from active RA patients, while it was increased in serum from active RA patients. HMGB1 plays a pivotal role in the pathogenesis of RA and may be a target of therapy as a novel cytokine.

[Significance of heat shock protein 70 in cerebrospinal fluid in differential diagnosis of central nervous system infection in children].

OBJECTIVE: To investigate the diagnostic value of heat shock protein 70 (HSP70) in central nervous system infection (CNSI) in children. METHODS: The level of HSP70 in the cerebrospinal fluid (CSF) was determined in children with CNSI of different etiology. The concentration of HSP70 was determined in the CSF of 104 children, among them 13 patients had purulent meningitis (PM), 38 patients had acute viral meningitis (VM), 7 patients had tuberculous meningitis (TM), and 46 with no CNSI to serve as controls. The concentration of HSP70 was determined by Western blotting assay. The CSF specimens were also analyzed for the total cellular score (TCS), white blood cell count (WBC), lactate dehydrogenase (LDH), protein content (PC), adenosine deaminase (ADD), glucose, chloride content (Cl(í)), and pressure. RESULTS: The CSF level of HSP70 was significantly higher in the PM, TM and VM groups [76.61+/-27.69, 65.85+/-33.16, 33.65+/-16.93] compared with the control group (23.28+/-19.77) (P<0.05 or P<0.01). The HSP70 concentration was markedly higher in the CSF of patients with PM and TM than patients with VM (both P<0.01). No significant difference was found between PM group and TM group in HSP70 level in CSF (P>0.05). The concentration of HSP70 in the CSF was positively correlated to TCS (r=0.298, P=0.002), WBC (r=0.274, P=0.005), LDH (r=0.322, P=0.001), PC (r=0.629, P<0.001), ADD (r=0.363, P<0.001), and negatively correlated to the glucose (r=-0.443, P<0.001) in CSF. The HSP70 concentration was not correlated to the Cl(í) (r=0.148, P=0.133) and pressure (r=0.001, P=0.993) of CSF. CONCLUSION: HSP70 is increased in the CSF of patients with CNSI. It may be one of the pathophysiological mechanisms of acute infection of the central nervous system. The level of HSP70 in CSF may be a valuable index in the differential diagnosis of CNSI, and it may be helpful in differentiating PM and TM from VM.

[Effect of Krüppel-like factor 4 overexpression on heat stress-induced apoptosis of Raw264.7 macrophages].

OBJECTIVE: To observe the effect of Krüppel-like factor 4 (KLF4) overexpression on heat stress-induced apoptosis of Raw264.7 macrophages. METHODS: The fragment containing full length mouse KLF4 cDNA coding sequence was inserted into the pcDNA3.1 vector and Raw264.7 macrophages were transfected with pcDNA3.1-KLF4 plasmids using lipofectamine.The expression of KLF4 was examined by Western blot in the Raw264.7 macrophages stably transfected with pcDNA3.1- KLF4 plasmids. Raw264.7 cells transfected with pcDNA3.1 and pcDNA3.1-KLF4 were exposed to heat stress (42 degrees C) for 1h and recovered at 37 degrees C for 12h. Flow cytometry, Hoechest 33258 staining assay, and DNA ladder assays were performed to assess the apoptosis. RESULTS: The KLF4 overexpressed Raw264.7 macrophages were established. After the heat stress, flow cytometry showed that apoptotic cells increased significantly in KLF4 overexpressed cells compared with the vector control; Hoechest 33258 staining was characterized with classical changes including apoptotic body, and nuclear condensation. Agarose gel electrophoresis showed that "DNA ladder" could be observed clearly. CONCLUSION: KLF4 overexpression can increase heat stress-induced apoptosis of Raw264.7 macrophages.

Puerarin inhibits expression of tissue factor induced by oxidative low-density lipoprotein through activating the PI3K/Akt/eNOS pathway and inhibiting activation of ERK1/2 and NF-κB.

AIMS: The present study aimed to investigate whether puerarin regulated tissue factor (TF) expression induced by oxidative low-density lipoprotein (ox-LDL), an independent risk factor for atherosclerosis, and its mechanisms. MAIN METHODS: TF expression at the mRNA level was determined by reverse transcription-quantitative polymerase chain reaction, and its expression at the protein level, as well as other target proteins, was assessed by western blotting. Nitric oxide (NO) production was measured by a nitrate reduction method. KEY FINDINGS: Results demonstrated that treatment with ox-LDL (50mg/l) for 24h significantly increased (P<0.01) TF expression at the mRNA and protein levels in human umbilical vein endothelial cells (HUVECs). Such an ox-LDL exposure also triggered the dephosphorylation of Akt, resulting in a reduction of NO production and activated the extracellular signal-regulated kinase (ERK)1/2 and nuclear factor (NF)-κB signaling pathways. Pre-treatment with puerarin (50-200µM) for 1h significantly attenuated the ox-LDL-induced TF expression, augmented the phosphorylation of Akt, with a resultant increase of the NO production, and inhibited the activation of ERK1/2 and NF-κB (P<0.01). However, this beneficial effect of puerarin (100µM) was abolished by LY294002 (10µM), an inhibitor of phosphoinositide 3-kinase (PI3K), or NG-nitro-L-arginine methyl ester (100µM), an inhibitor of NO synthase. SIGNIFICANCE: These results suggested that puerarin suppressed TF expression in HUVECs through activating the PI3K/Akt/endothelial nitric oxide synthase signaling pathway and inhibiting the activation of ERK1/2 and NF-κB. These findings suggested that puerarin possessed certain anticoagulation and may be a potential novel therapeutic drug for thrombosis in coronary artery disease.

[CoCl2-induced chemotherapy resistance in SW480 cells and its mechanism].

OBJECTIVE: To observe the proliferation of SW480 cells exposed to different concentrations of CoCl2, and to examine the expression of hypoxiainducible factor-1 alpha (HIF-1alpha) and heme oxygenase-1 (HO-1) during hypoxia to explore the chemotherapy resistance effect and role of HIF-1alpha and HO-1. METHODS: Methyl thiazolyl tetrazolium (MTF) method was used to detect the proliferation of SW480 cells in the presence of fluorouracil (FU). RT-PCR was applied to examine the expression of HIF-1alpha and HO-1 mRNA in hypoxia. RESULTS: SW480 cells were proliferated at a slow rate, and had a strong resistance to FU with the increase of CoCl2. RT-PCR showed that the up-regulated expression of HIF-1alpha and HO-1 mRNA was consistent with the dose-effect curve and time-effect curve. CONCLUSION: The hypoxia induced by CoCl2 can inhibit the proliferation of SW480, and it can also decrease the sensitivity of the cell to FU. The mechanism is probably related to the up-regulated expression of HIF-1alpha and HO-1 mRNA.

[Killing effect of VP3 on human nasopharyngeal carcinoma cell line CNE-2 cells].

OBJECTIVE: To investigate the killing effects of VP(3) on nasopharyngeal carcinoma cell line CNE-2. METHODS: Plasmid expression vector pcDNA3.1(-) CMV.VP(3)-His was constructed and identified by Kpn I/EcoR I endonuclease analysis, and then sequenced to verify successful insertion in the sense direction of VP(3) gene. pcDNA3.1(-) CMV.VP(3)-His and pcDNA3.1(-)-His expression plasmid was transiently transfected into nasopharyngeal carcinoma cell line CNE-2 . VP(3) protein expression was detected by Western blotting. MTT assay was used to determine the killing effects of VP(3) gene on nasopharyngeal carcinoma cell line CNE-2. RESULTS: Endonuclease analysis and sequencing confirmed the recombinant plasmid contained the complete VP(3) CDS sequence. Western blotting detected a 14.03 kD protein expression from the transfected cells, which was the expecting band of VP(3) gene. The growth of CNE-2 cells that expressed VP(3) gene was inhibited,while the growth of CNE-2 cells that did not express VP(3) gene was not inhibited. CONCLUSION: VP(3) gene can kill nasopharyngeal carcinoma cell CNE-2.

[HSF1 inhibits heat stress-induced apoptosis in Raw264.7 macrophages].

OBJECTIVE: To observe the effect of heat shock factor 1 (HSF1) on heat stress-induced apoptosis in Raw264.7 macrophages. METHODS: Raw264.7 cells transfected with pcDNA3.1 and pcDNA3.1-HSF1 were exposed to heat stress (42.5 degrees C +/- 0.5 degrees C) for 1 h and recovered at 37 degrees C for 6, 9, 12, and 24 h respectively. Flow cytometry (FCM), Hoechst 33258 staining and DNA ladder assays were performed to assess the apoptosis. RESULTS: After heat stress, FCM showed that apoptotic cells were increased significantly and reached the peak at 9 h in Raw 264.7 cells transfected with pcDNA3.1, and were characterized with classical morphologic changes including apoptotic body and nuclear condensation. Agarose gel electrophoresis showed that "DNA ladder" could be observed clearly at 6, 9, and 12 h after the heat stress. But the overexpression of HSF1 could reduce the number of apoptotic cells and inhibit DNA fragmentation. CONCLUSION: HSF1 can inhibit heat stress-induced apoptosis in Raw264.7 macrophages.