Objective To verify tissue factor (TF)-bearing microparticle (TF-MP) could be released from Kupffer cells (KCs) stimulated by lipopolysaccharide (LPS) and TF controlled by Toll-like receptor 4 (TLR4) could induce acute pancreatitis. Methods After the acute pancreatitis model completed, the wild type C57/BL6 mouse (WT group) and the TLR4-/- mouse (TLR4-/- group) received intraperitioneal injections of 10 mg/kg LPS. The degree of pathological lesion and the TF expression were detected in the pancreas tissue. The TF and TLR4 protein and mRNA expressions in the KCs were detected at 6, 12, and 24 h after the last injection of LPS. The survival rates were campared in these estabilshed acute pancreatitis model mice. The TF and TLR4 protein and mRNA expressions in the KCs stimulated with LPS (300 μg/L) were also detected at 0, 15, 30, 60, and 120 min. The TF and TF-MP levels were detected in the supernatants of the KCs at these time point. Results The injury of the pancreas in the TLR4-/- group was slighter than that in the WT group. The TF proteins in the liver and pancreas tissues of the TLR4-/- group were significantly lower than those of the WT group (P<0.05). The survival rate of the TLR4-/- group was significantly higher than that of the WT group under the situation of the acute pancreatitis (P<0.05). The TLR4 and TF protien and mRNA expressions of the KCs were significantly decreased in the TLR4-/- group as compared with the WT group at 30, 60, and 120 min (P<0.05). The levels of TF and TF-MP in the supernatant of the TLR4-/- group were significantly lower than those of the WT group at 30, 60, and 120 min (P<0.05). Conclusion Acute pancretitis can be induced by TF and TF-MP expressions in KCs which could be regulated by TLR4 pathway.
ObjectiveTo explore the relationship between single nucleotide polymorphisms (SNPs) of the Toll-like receptor 4 (TLR4) gene and the risk of pulmonary tuberculosis (PTB) more comprehensively and objectively through meta-analysis.MethodsWe searched all available articles published before June 13th, 2019 in main Chinese and English databases systematically and comprehensively, including PubMed, Embase, China National Knowledge Infrastructure, Wanfang and CQVIP databases. The literature was screened according to the inclusion and exclusion criteria set in advance. In addition, the basic characteristics and data of the included literature were recorded according to a pre-made data collection form. Statistical analyses were performed using the Stata 15.0 software.ResultsA total of 17 eligible original articles were included in the study eventually. Furthermore, allele and genotype data of the 4 most widely studied SNPs (rs4986790, rs4986791, rs10759932, and rs11536889) in the TLR4 gene were extracted. And their allelic model, dominant model, recessive model, homozygous model, and heterozygous model were separately analyzed by meta-analysis. The results showed that the C allele of rs10759932 increased the risk of PTB [odd ratio (OR)=1.144, 95% confidence interval (CI) (1.043, 1.254), P=0.004]. Compared with the TT genotype, the CC+CT genotype and the CT genotype alone of rs10759932 also increased the risk of PTB [OR=1.218, 95%CI (1.084, 1.369), P=0.001; OR=1.227, 95%CI (1.085, 1.387), P=0.001]. Nevertheless, there was no statistical correlation between the other three SNPs (rs4986790, rs4986791 and rs11536889) and the susceptibility to PTB (P>0.05).ConclusionThe allele model, dominant model (CC+CT vs. TT), and heterozygous model (CT vs. TT) of rs10759932 located on the TLR4 gene are closely related to the risk of PTB.
ObjectiveTo observe the protective effect of tanshinone Ⅱ A on the mouse liver ischemia-reperfusion injury (IRI) model and preliminarily explore its mechanism of alleviating liver injury.MethodsThe IRI mouse model was established after the pre-treating with tanshinone Ⅱ A. Then, the serum and liver tissue of mice were collected to detect the changes of liver function, histopathology, liver cell apoptosis, and inflammatory factors. In addition, the protein expression levels of high mobility group box 1 (HMGB1), advanced glycosylation end-product specific receptor (RAGE), and Toll like receptor 4 (TLR4) in the liver tissues were detected by the Western blot method.ResultsAll data were analyzed by the homogeneity of variance test. The results of factorial design showed that the levels of ALT and AST in the serum, the pathological score and apoptosis index, the inflammatory response, as well as the expressions of HMGB1, TLR4 and RAGE proteins in the liver tissues were decreased significantly (P<0.05) in the sham operatation plus tanshinone Ⅱ A mice, which were increased significantly (P<0.05) in the IRI mice, which were antagonized synergistically by the tanshinone ⅡA and IRI (P<0.05).ConclusionsTanshinone ⅡA could reduce the liver IRI and inflammatory response in mouse. These effects might be related to the down-regulations of TLR4, HMGB1, and RAGE expressions.
ObjectiveTo investigate the protective effect and mechanism of curcumin on lipopolysaccharide (LPS)-induced acute lung injury.MethodsTotally 24 SD rats were randomly divided into a control group, a LPS group and a LPS+curcumin group (n=8 in each group). The degree of lung injury (oxygen partial pressure, wet/dry ratio, pathological scores) and inflammatory levels [tumor necrosis factor (TNF)-α, interleukin (IL)-6, monocyte chemotactic protein (MCP)-1, Toll-like receptor 4 (TLR4), mobility group box 1 protein (HMGB1) expression] of the lung were detected in different groups.ResultsOxygen partial pressure was significantly lower in the LPS group than that in the control group (P<0.05), while wet/dry ratio, pathological scores and expression levels of TNF-α, IL-6, MCP-1, TLR4 and HMGB1 were significantly higher in the LPS group than those in the control group (P<0.05). Compared with the LPS group, curcumin significantly reduced wet/dry ratio, pathological scores and expression levels of TNF-α, IL-6, MCP-1, TLR4 and HMGB1 in the LPS+curcumin group (P<0.05), while it significantly improved oxygen partial pressure (P<0.05).ConclusionCurcumin might protect LPS-induced acute lung injury through inhibition of TLR4-HMGB1-inflammation pathway.
ObjectiveTo investigate the effect and mechanism of microRNA (miR)-146a-3p on acute lung injury (ALI) and inflammation induced by lipopolysaccharide (LPS) in mice.MethodsThirty-two BALB/c mice were randomly divided into sham group, ALI group, ALI+agomiR-negative control (NC) group, ALI+miR-146a-3p agonist (agomiR-146a-3p) group, with 8 mice in each group. The ALI model was established by instilling 5 mg/kg LPS into the lungs through the trachea, and the same amount of saline was instilled slowly in the sham group. The mice in the ALI+agomiR-146a-3p group/NC group were injected with 8 mg/kg agomiR-146a-3p or agomiR-NC respectively through the tail vein, once a day, for 3 days. The sham group and the model group were given the same amount of normal saline injection through the tail vein. After 24 hours, they were sacrificed and lung tissues were collected. The expressions of miR-146a-3p and toll-like receptor 4 (TLR4) mRNA in lung tissue were detected by RT-qPCR, the expression levels of TLR4, cleaved caspase-3, Bcl-2 related X protein (Bax), B cell lymphoma-2 (Bcl-2) protein in lung tissue were detected by Western blot. The changes of lung pathology were observed by hematoxylin-eosin staining. The apoptosis of lung tissue was detected by TdT-mediated dUTP nick-end labeling. The expression levels of IL-1β, IL-6 and TNF-α in lung tissue were detected by enzyme-linked immunosorbent assay (ELISA). The dual luciferase reporting system verified the targeting relationship between miR-146a-3p and TLR4 in MRC-5 cells. MRC-5 cells were divided into control group, LPS group, LPS+miR-146a-3p mimic group, LPS+pcDNA3.1(pc)-TLR4 group, LPS+miR-146a-3p mimic+pc-TLR4 group. 100 nmol/L miR-146a-3p mimic and pc-TLR4 plasmids were transfected into MRC-5 cells separately or jointly for 24 hours, and then treated with 1000 ng/mL LPS or normal saline for 72 hours. The apoptosis rate was detected by flow cytometry. The expression levels of TLR4, cleaved caspase-3, Bax, and Bcl-2 proteins were detected by Western blot. The levels of IL-1β, IL-6 and TNF-α were detected by ELISA.ResultsCompared with the ALI group, the expression of miR-146a-3p was up-regulated, the expressions of TLR4 mRNA and protein were down-regulated, the apoptotic rate was decreased, the expressions of cleaved caspase-3 and Bax protein was down-regulated, the expression of Bcl-2 protein was up-regulated, and the levels of TNF-α, IL-6 and IL-1β in lung tissue were decreased in the lung tissues of the ALI+agomiR-146a-3p group (P<0.05). Dual-luciferase reporter assay confirmed that miR-146a-3p regulates transcription by targeting TLR4 3’UTR sequence (P<0.05). Compared with the LPS group, the expression of TLR4 protein in MRC-5 cells of the LPS+miR-146a-3p mimic group was down-regulated, the apoptosis was reduced, the expressions of cleaved caspase-3 and Bax protein were down-regulated, and the levels of TNF-α, IL-6 and IL-1β in lung tissue were decreased (P<0.05). Overexpression of TLR4 reversed the effect of miR-146a-3p mimic overexpression on LPS-induced apoptosis and inflammation of MRC-5 cells (P<0.05).ConclusionmiR-146a-3p alleviates LPS-induced ALI in mice by down-regulating TLR4.