Expression of tissue factor pathway inhibitor-2 in murine and human liver regulation during inflammation

Expression analysis of tissue factor pathway inhibitors TFPI-1 and TFPI-2 in Paralichthys olivaceus and antibacterial and anticancer activity of derived peptides

Tissue factor pathway inhibitors (TFPI), including TFPI-1 and TFPI-2, are Kunitz-type serine protease inhibitors that mainly inhibit the blood coagulation induced by tissue factors. Previous reports on teleost proved TFPI play important roles in innate immunity. In this study, two TFPI (PoTFPI-1 and PoTFPI-2) molecules from Japanese flounder (Paralichthys olivaceus) were analyzed and characterized for their expression patterns, antibacterial and anticancer activities of the C-terminal derived peptides. Quantitative real time RT-PCR analysis shows that constitutive PoTFPI-1 expression occurred, in increasing order, in the brain, muscle, spleen, gills, head kidney, blood, intestine, heart, and liver; PoTFPI-2 was expressed, in increasing order, in the brain, gills, head kidney, muscle, intestine, spleen, liver, heart, and blood. Under the stimulation of fish pathogens, both PoTFPI-1 and PoTFPI-2 expressions increased significantly in a manner that depended on the pathogens, tissue type, and infection stage. Furthermore, C-terminal peptides TP25 and TP26, derived from PoTFPI-1 and PoTFPI-2, respectively, were synthesized and proved to be active against Micrococcus luteus (for TP25 and TP26) and Staphylococcus aureus (for TP25) via retardation effects on bacterial nucleic acids. In addition, TP25 and TP26 also displayed significant inhibitory effects on human colon cancer cell line HT-29. These results reveal that both PoTFPI-1 and PoTFPI-2 play important roles in host innate immunity. The antibacterial activity and anticancer cells function of TP25 and TP26 will add new insights into the roles of teleost TFPI.

Tissue factor pathway inhibitor in atherosclerosis

Tissue factor pathway inhibitor (TFPI) reduces the development of atherosclerosis by regulating tissue factor (TF) mediated coagulation pathway. In this review, we focus on recent findings on the inhibitory effects of TFPI on endothelial cell activation, vascular smooth muscle cell (VSMC) proliferation and migration, inflammatory cell recruitment and extracellular matrix which are associated with the development of atherosclerosis. Meanwhile, we are also concerned about the impact of TFPI levels and genetic polymorphisms on clinical atherogenesis. This article aims to explain the mechanism in inhibiting the development of atherosclerosis and clinical effects of TFPI, and provide new ideas for the clinical researches and mechanism studies of atherothrombosis.

Molecular characterization, expression analysis, and bactericidal activity of the derivative peptides of TFPI-1 and TFPI-2 in half-smooth tongue sole, Cynoglossus semilaevis

Tissue factor pathway inhibitors (TFPIs) are Kunitz-type serine protease inhibitors that reversibly regulate the blood coagulation induced by tissue factor. TFPI family contain two members, TFPI-1 and TFPI-2. Recent studies have shown TFPI-1 and TFPI-2 also play important roles in innate immunity, however, the potential function of teleost TFPI are very limited. In this study, we characterized two TFPI (CsTFPI-1 and CsTFPI-2) molecules from half-smooth tongue sole (Cynoglossus semilaevis), examined their tissue distributions and expression patterns under pathogens stimulation as well as investigated the antibacterial activity of the C-terminal peptides. Quantitative real time RT-PCR analysis showed that constitutive CsTFPI-1 expression occurred, in increasing order, in head kidney, intestine, brain, spleen, liver, skin, gills, heart, and muscle; CsTFPI-2 was expressed, in increasing order, in the gills, intestine, skin, head kidney, liver, brain, spleen, muscle, and heart. Under Vibrio anguillarum, Streptococcus agalactiae and fish megalocytivirus stimulation, both CsTFPI-1 and CsTFPI-2 expression increased significantly in a manner that depended on the pathogen, tissue type, and infection stage, which suggested CsTFPI-1 and CsTFPI-2 play important roles in anti-bacterial and anti-viral infection. Finally, C-terminal peptides of CsTFPI-1 and CsTFPI-2, were synthesized and proved to have antibacterial effect against Micrococcus luteus that were independent of host serum. Take together, these results indicate that CsTFPI-1 and CsTFPI-2 play important roles in antimicrobial immunity of this fish.

Vertebrate TFPI-2 C-terminal peptides exert therapeutic applications against Gram-negative infections

BACKGROUND

Tissue factor pathway inhibitor-2 (TFPI-2) is a serine protease inhibitor that exerts multiple physiological and patho-physiological activities involving the modulation of coagulation, angiogenesis, tumor invasion, and apoptosis. In previous studies we reported a novel role of human TFPI-2 in innate immunity by serving as a precursor for host defense peptides. Here we employed a number of TFPI-2 derived peptides from different vertebrate species and found that their antibacterial activity is evolutionary conserved although the amino acid sequence is not well conserved. We further studied the theraputic potential of one selected TFPI-2 derived peptide (mouse) in a murine sepsis model.

RESULTS

Hydrophobicity and net charge of many peptides play a important role in their host defence to invading bacterial pathogens. In vertebrates, the C-terminal portion of TFPI-2 consists of a highly conserved cluster of positively charged amino acids which may point to an antimicrobial activity. Thus a number of selected C-terminal TFPI-2 derived peptides from different species were synthesized and it was found that all of them exert antimicrobial activity against E. coli and P. aeruginosa. The peptide-mediated killing of E. coli was enhanced in human plasma, suggesting an involvement of the classical pathway of the complement. Under in vitro conditions the peptides displayed anti-coagulant activity by modulating the intrinsic pathway of coagulation and in vivo treatment with the mouse derived VKG24 peptide protects mice from an otherwise lethal LPS shock model.

CONCLUSIONS

Our results suggest that the evolutionary conserved C-terminal part of TFPI-2 is an interesting agent for the development of novel antimicrobial therapies.

The coagulation system and its function in early immune defense

Blood coagulation has a Janus-faced role in infectious diseases. When systemically activated, it can cause serious complications associated with high morbidity and mortality. However, coagulation is also part of the innate immune system and its local activation has been found to play an important role in the early host response to infection. Though the latter aspect has been less investigated, phylogenetic studies have shown that many factors involved in coagulation have ancestral origins which are often combined with anti-microbial features. This review gives a general overview about the most recent advances in this area of research also referred to as immunothrombosis.

The TFPI-2 derived peptide EDC34 improves outcome of gram-negative sepsis

Sepsis is characterized by a dysregulated host-pathogen response, leading to high cytokine levels, excessive coagulation and failure to eradicate invasive bacteria. Novel therapeutic strategies that address crucial pathogenetic steps during infection are urgently needed. Here, we describe novel bioactive roles and therapeutic anti-infective potential of the peptide EDC34, derived from the C-terminus of tissue factor pathway inhibitor-2 (TFPI-2). This peptide exerted direct bactericidal effects and boosted activation of the classical complement pathway including formation of antimicrobial C3a, but inhibited bacteria-induced activation of the contact system. Correspondingly, in mouse models of severe Escherichia coli and Pseudomonas aeruginosa infection, treatment with EDC34 reduced bacterial levels and lung damage. In combination with the antibiotic ceftazidime, the peptide significantly prolonged survival and reduced mortality in mice. The peptide's boosting effect on bacterial clearance paired with its inhibiting effect on excessive coagulation makes it a promising therapeutic candidate for invasive Gram-negative infections.

Bacterial infections, especially sepsis, are worldwide a major cause of morbidity and mortality. Sepsis is characterized by an excessive and uncontrolled immune and coagulation response caused by bacteria and bacterial products, which eventually leads to multiple organ failure. Despite supportive treatments and administration of antibiotics, the incidence of sepsis is rising. Development of antibiotic resistance among bacteria, and the inability of antibiotics to target dysregulated host responses during severe infections and sepsis, motivates the search for novel anti-infective treatment modalities. Here, we describe a therapeutic potential of the peptide EDC34, derived from the C-terminus of tissue factor pathway inhibitor-2 (TFPI-2). The peptide's boosting effect on bacterial clearance paired with its inhibiting effect on excessive coagulation makes it a promising therapeutic candidate for invasive Gram-negative infections.

Tissue factor pathway inhibitor 2 is found in skin and its C-terminal region encodes for antibacterial activity

Background

Tissue factor pathway inhibitor 2 (TFPI-2) is a matrix-associated serine protease inhibitor with an enigmatic function in vivo. Here, we describe that TFPI-2 is present in fibrin of wounds and also expressed in skin, where it is up-regulated upon wounding.

Methodology and Principal Findings

Neutrophil elastase cleaved TFPI-2, and a C-terminal fragment was found to bind to bacteria. Similarly, a prototypic peptide representing this C-terminal part, EDC34, bound to bacteria and bacterial lipopolysaccharide, and induced bacterial permeabilization. The peptide also induced leakage in artificial liposomes, and displayed a random coil conformation upon interactions with liposomes as well as lipopolysaccharide. EDC34 was antibacterial against both Gram-negative and Gram-positive bacteria in physiological buffer conditions.

Conclusions/Significance

The results demonstrate that the C-terminus of TFPI-2 encodes for antimicrobial activity, and may be released during wounding.

Adenovirus-mediated gene transfer of tissue factor pathway inhibitor-2 inhibits gallbladder carcinoma growth in vitro and in vivo

Tissue factor pathway inhibitor-2 (TFPI-2) has been identified as a tumor suppressor gene in several types of cancers, but its role in gallbladder carcinoma (GBC) is yet to be determined. In the present study, TFPI-2 expression in GBC tissues was examined, and its inhibitory activities against GBC growth were evaluated in vitro and in vivo after adenovirus-mediated gene transfer of TFPI-2 (Ad5-TFPI-2) was constructed to restore the expression of TFPI-2 in GBC cell lines (GBC-SD, SGC-996, NOZ) and xenograft tumors. Immunohistochemical staining showed that TFPI-2 was significantly downregulated in GBC tissue specimens. Ad5-TFPI-2 could significantly inhibit GBC growth both in vitro and in vivo. Apoptosis analysis and western blotting assay demonstrated that Ad5-TFPI-2 could induce the apoptosis of both GBC cell lines and tissues by promoting the activities of cytochrome c, Bax, caspase-3 and -9 and suppressing Bcl-2 activity. These data indicated that TFPI-2 acts as a tumor suppressor in GBC, and may have a potential role in gene therapy for GBC.

Glucagon counteracts interleukin-6-dependent gene expression by redundant action of Epac and PKA

Inflammation is the biological response to injurious stimuli. In the initial phase of the inflammatory process, interleukin-6 (IL-6) is the main inducer of acute phase protein expression in the liver. A prolonged acute phase response is characterised by a disturbed glucose homeostasis and elevated levels of IL-6, insulin, and counterregulatory hormones such as glucagon. Several studies deal with the impact of IL-6 on glucagon-dependent gene expression. In contrast, only very little is known about the influence of G-protein-coupled receptors on IL-6 signalling. Therefore, the aim of this study is to elucidate the regulation of IL-6-induced gene expression by glucagon. We could reveal a novel mechanism of negative regulation of IL-6-induced MAP kinase activation by glucagon in primary murine hepatocytes. IL-6-dependent induction of the ERK-dependent target geneTfpi2, coding for a Kunitz-type serine protease inhibitor, was strongly down-regulated by glucagon treatment. Studying the underlying mechanism revealed a redundant action of the signalling molecules exchange protein activated by cyclic AMP (Epac) and protein kinase A. The metabolic hormone glucagon interferes in IL-6-induced gene expression. This observation is indicative for a regulatory role of G-protein-coupled receptors in the IL-6-dependent inflammatory response.

Molecular regulation of vasculogenic mimicry in tumors and potential tumor-target therapy

“Vasculogenic mimicry (VM)”, is a term that describes the unique ability of highly aggressive tumor cells to express a multipotent, stem cell-like phenotype, and form a pattern of vasculogenic-like networks in three-dimensional culture. As an angiogenesis-independent pathway, VM and/or periodic acid-schiff-positive patterns are associated with poor prognosis in tumor patients. Moreover, VM is resistant to angiogenesis inhibitors. Here, we will review the advances in research on biochemical and molecular signaling pathways of VM in tumors and on potential anti-VM therapy strategy.

Genome-wide transcriptome profiling of region-specific vulnerability to oxidative stress in the hippocampus

Neurons in the hippocampal CA1 region are particularly sensitive to oxidative stress (OS), whereas those in CA3 are resistant. To uncover mechanisms for selective CA1 vulnerability to OS, we treated organotypic hippocampal slices with duroquinone and compared transcriptional profiles of CA1 vs CA3 cells at various intervals. Gene Ontology and Biological Pathway analyses of differentially expressed genes showed that at all time points, CA1 had higher transcriptional activity for stress/inflammatory response, transition metal transport, ferroxidase, and presynaptic signaling activity, while CA3 had higher GABA-signaling, postsynaptic, and calcium and potassium channel activity. Real-time PCR and immunoblots confirmed the transcriptome data and the induction of OS by duroquinone in both hippocampal regions. Our functional genomics approach has identified in CA1 cells molecular pathways as well as unique genes, such as guanosine deaminase, lipocalin 2, synaptotagmin 4, and latrophilin 2, whose time-dependent induction following the initiation of OS may represent attempts at neurite outgrowth, synaptic recovery, and resistance against OS.

Tissue Factor Pathway Inhibitor-2 Is Upregulated by Vascular Endothelial Growth Factor and Suppresses Growth Factor-Induced Proliferation of Endothelial Cells

Objective— The purpose of this study is to investigate the expression and regulation of type-2 tissue factor pathway inhibitor (TFPI-2) in endothelial cells, as well as the regulation of human endothelial cell (EC) function by TFPI-2.

Methods and Results— Real-time polymerase chain reaction (PCR) and Western blot analysis revealed that vascular endothelial growth factor (VEGF) induced both time- and dose-dependent increase in TFPI-2 mRNA and protein expression in endothelial cells. TFPI-2 mRNA expression was also significantly upregulated by IL-1β, and modestly increased by both tumor necrosis factor (TNF)-α and fibroblast growth factor (FGF)-2, but not placental growth factor (PlGF). VEGF upregulation of TFPI-2 was dramatically reduced by inhibition of the MEK pathway. Administration of TFPI-2 protein suppressed both VEGF and FGF-2 stimulation of EC proliferation in a dose-dependent manner. A recombinant preparation of the first Kunitz-type domain of TFPI-2 (KD1) did not suppress growth factor stimulation of EC proliferation, suggesting a mechanism distinct from the proteinase inhibitory activity of TFPI-2. Exogenously added TFPI-2 protein suppressed VEGF-induced EC migration in 2 different assays. Recombinant wt-KD1 or the R24K mutant of KD1, but not the R24Q mutant, dramatically suppressed VEGF-induced EC migration. TFPI-2 protein, but not recombinant KD1, blocked VEGF-induced activation of both Akt and ERK1/2 in ECs. At higher doses, TFPI-2 protein blocked VEGFR2 activation.

Conclusion— Our data suggest that VEGF-upregulation of TFPI-2 expression in endothelial cells may represent a mechanism for negative feedback regulation and modulation of its pro-angiogenic action on endothelial cells. TFPI-2, or derivatives of TFPI-2, may be novel therapeutics for treatment of angiogenic disease processes.