Search results for "Peptidase"
showing 10 items of 567 documents
On the roles of Notch, Delta, kuzbanian, and inscuteable during the development of Drosophila embryonic neuroblast lineages
2009
AbstractThe generation of cellular diversity in the nervous system involves the mechanism of asymmetric cell division. Besides an array of molecules, including the Par protein cassette, a heterotrimeric G protein signalling complex, Inscuteable plays a major role in controlling asymmetric cell division, which ultimately leads to differential activation of the Notch signalling pathway and correct specification of the two daughter cells. In this context, Notch is required to be active in one sibling and inactive in the other. Here, we investigated the requirement of genes previously known to play key roles in sibling cell fate specification such as members of the Notch signalling pathway, e.g…
Neuronal activity triggers uptake of hematopoietic extracellular vesicles in vivo
2019
Communication with the hematopoietic system is a vital component of regulating brain function in health and disease. Traditionally, the major routes considered for this neuroimmune communication are by individual molecules such as cytokines carried by blood, by neural transmission, or, in more severe pathologies, by the entry of peripheral immune cells into the brain. In addition, functional mRNA from peripheral blood can be directly transferred to neurons via extracellular vesicles (EVs), but the parameters that determine their uptake are unknown. Using varied animal models that stimulate neuronal activity by peripheral inflammation, optogenetics, and selective proteasome inhibition of dop…
Glucose-independent improvement of vascular dysfunction in experimental sepsis by dipeptidyl-peptidase 4 inhibition.
2012
Aims Dipeptidyl peptidase-4 (DPP-4) inhibitors are a novel class of drugs for the treatment of hyperglycaemia. Preliminary evidence suggests that their antioxidant and anti-inflammatory effects may have beneficial effects on the cardiovascular complications of diabetes. In the present study, we investigate in an experimental sepsis model whether linagliptin exerts pleiotropic vascular effects independent of its glucose-lowering properties. Methods and results Linagliptin (83 mg/kg chow for 7days) was administered in a rat model of lipopolysaccharide (LPS) (10 mg/kg, single i.p. dose/24 h)-induced sepsis. Vascular relaxation, reactive oxygen species (ROS) formation, expression of NADPH oxida…
Tissue inhibitor of metalloproteinases-2 (TIMP-2) in rat liver cells is increased by lipopolysaccharide and prostaglandin E2
1995
AbstractTo explore the functional role of TIMP-2 in liver, we determined TIMP-2 mRNA levels in primary rat hepatocytes and in total rat liver. Rat hepatocytes constitutively express TIMP-2 mRNA at a low level. Incubation with dexamethasone, prostaglandin E2 and a combination of inflammatory cytokines leads to an up-regulation of TIMP-2 mRNA. In rats in vivo we found a dramatic increase of TIMP-2 expression after intraperitoneal injection of lipopolysaccharide. Compared to our previous findings on TIMP-1 we conclude that TIMP-2 mRNA expression is regulated in a distinct and partially opposite manner. Over-production of TIMP-2 could inhibit the activity of metalloproteinases and thus lead to …
Mer Tyrosine Kinase (MERTK) modulates liver fibrosis progression and hepatocellular carcinoma development.
2022
BackgroundMerTK is a tyrosine kinase receptor that belongs to the TAM (Tyro3/Axl/Mer) receptor family. It is involved in different processes including cellular proliferation/survival, cellular adhesion/migration, and release of the inflammatory/anti-inflammatory cytokines. Although it is reported that MERTK polymorphisms affect the severity of viral and metabolic liver diseases, being able to influence fibrosis progression and hepatocellular carcinoma development, the mechanisms remain unknown. Methods: using a microarray approach, we evaluated the liver expression of genes involved in fibrogenesis and hepatocarcinogenesis in patient with chronic hepatitis C (CHC), stratified for MERTK geno…
Evaluation of soluble CD 14 and neopterin as serum parameters of the inflammatory activity of pulmonary sarcoidosis.
1992
CD14 represents the most specific marker for monocytes/macrophages. It has been demonstrated in vitro that monocytes/macrophages lose this antigen upon activation. Results of studies investigating the expression of membrane-bound CD14 on the surface of monocytes/macrophages in sarcoidosis patients are controversial. To investigate whether the soluble form of CD14 reflects monocyte/macrophage activation in sarcoidosis, serum levels of soluble CD14 were determined concurrently with other serum markers of monocyte/macrophage activation (neopterin, angiotensin-converting enzyme) in 50 consecutive patients with bioptically confirmed sarcoidosis. The patients were allocated to three groups accord…
DPP-4 is overexpressed in lung tissue from idiopathic pulmonary patients and activates lung fibroblasts
2020
Background: Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible form of fibrotic interstitial lung disease, characterized by uncontrolled fibroblast invasion. Dipeptidyl peptidase-4 (DPP-4)/ glucagon-like peptide 1 (GLP-1) system is involved in multiple effects, including cardiac, liver or kidney fibrosis. However, its implication in IPF has not been described. Objective: To analyse the implication of DPP4/GLP1 system in IPF. Methods: Protein expression of DPP4, GLP-1 and GLP-1 receptor was analyzed in lung tissues from 7 IPF patients. TGFβ1-induced fibroblast to myofibroblast transition (FMT), epithelial to mesenchymal transition (EMT) and mesothelial to mesenchymal trans…
Antigen-processing machinery breakdown and tumor growth.
2000
Defects in the major histocompatibility complex (MHC) class I antigen-processing machinery (APM) have been described in tumors of different histology. Murine data suggest that defects in the MHC class II APM might also be associated with malignant transformation of human cells. This article describes the pathophysiology of the MHC class I and II APM, reviews APM abnormalities in tumor cells and discusses their role in the escape of tumor cells from in vitro recognition by T cells.
Synthesis of Tetrapeptide p‐nitrophenylanilides containing dehydroalanine and dehydrophenylalanine and their influence on cathepsin C activity
2001
Three dehydrotetrapeptides of rationally varying structure were prepared and tested as affectors of cathepsin C. These compounds appeared to be substrates of the enzyme, being equipotent with their classical counterparts. Thus, replacement of amino acid in a short peptide by corresponding dehydroamino acid does not prevent cathepsin C in recognizing dehydropeptide as its substrate. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
New Tetromycin Derivatives with Anti-Trypanosomal and Protease Inhibitory Activities
2011
Four new tetromycin derivatives, tetromycins 1-4 and a previously known one, tetromycin B (5) were isolated from Streptomyces axinellae Pol001(T) cultivated from the Mediterranean sponge Axinella polypoides. Structures were assigned using extensive 1D and 2D NMR spectroscopy as well as HRESIMS analysis. The compounds were tested for antiparasitic activities against Leishmania major and Trypanosoma brucei, and for protease inhibition against several cysteine proteases such as falcipain, rhodesain, cathepsin L, cathepsin B, and viral proteases SARS-CoV M(pro), and PL(pro). The compounds showed antiparasitic activities against T. brucei and time-dependent inhibition of cathepsin L-like proteas…