scholarly journals Modulation of substance P signaling by dipeptidyl peptidase-IV enzymatic activity in human glioma cell lines

2008 ◽  
pp. 443-449
Author(s):  
P Bušek ◽  
J Stremeňová ◽  
E Křepela ◽  
A Šedo
Keyword(s):  
Substance P ◽  
Cell Surface ◽  
Intracellular Calcium ◽  
Dipeptidyl Peptidase ◽  
Dipeptidyl Peptidase Iv ◽  
Biologically Active ◽  
Wild Type ◽  
Surface Receptors ◽  
Dpp Iv ◽  
Stromal Cell Derived Factor

Dipeptidyl peptidase-IV (DPP-IV, CD26) is a serine protease almost ubiquitously expressed on cell surface and present in body fluids. DPP-IV has been suggested to proteolytically modify a number of biologically active peptides including substance P (SP) and the chemokine stromal cell derived factor-1α (SDF-1α, CXCL12). SP and SDF-1α have been implicated in the regulation of multiple biological processes and also induce responses that may be relevant for glioma progression. Both SP and SDF-1α are signaling through cell surface receptors and use intracellular calcium as a second messenger. The effect of DPP-IV on intracellular calcium mobilization mediated by SP and SDF-1α was monitored in suspension of wild type U373 and DPP-IV transfected U373DPPIV glioma cells using indicator FURA-2. Nanomolar concentrations of SP triggered a transient dose dependent increase in intracellular calcium rendering the cells refractory to repeated stimulation, while SDF-1α had no measurable effect. SP signaling in DPP-IV overexpressing U373DPPIV cells was not substantially different from that in wild type cells. However, preincubation of SP with the DPP-IV overexpressing cells lead to the loss of its signaling potential, which could be prevented with DPP-IV inhibitors. Taken together, DPP-IV may proteolytically inactivate local mediators involved in gliomagenesis.

scholarly journals Automatic Recognition of Muscle-Invasive T-Lymphocytes Expressing Dipeptidyl-Peptidase IV (CD26) and Analysis of the Associated Cell Surface Phenotypes

2002 ◽  
Vol 4 (1) ◽  
pp. 67-74 ◽  
Author(s):  
W. Schubert ◽  
M. Friedenberger ◽  
R. Haars ◽  
M. Bode ◽  
L. Philipsen ◽  
...  
Keyword(s):  
T Cells ◽  
T Lymphocytes ◽  
Cell Surface ◽  
Detection System ◽  
Dipeptidyl Peptidase ◽  
Dipeptidyl Peptidase Iv ◽  
Cell Detection ◽  
Surface Receptors ◽  
Dpp Iv ◽  
Muscle Invasive

A neural cell detection system (NCDS) for the automatic quantitation of fluorescent lymphocytes in tissue sections was used to analyze CD26 expression in muscle-invasive T-cells. CD26 is a cell surface dipeptidyl-peptidase IV (DPP IV) involved in co-stimulatory activation of T-cells and also in adhesive events. The NCDS system acquires visual knowledge from a set of training cell image patches selected by a user. The trained system evaluates an image in 2 min calculating (i) the number, (ii) the positions and (iii) the phenotypes of the fluorescent cells. In the present study we have used the NCDS to identity DPP IV (CD26) expressing invasive lymphocytes in sarcoid myopathy and to analyze the associated cell surface phenotypes. We find highly unusual phenotypes characterized by differential combination of seven cell surface receptors usually involved in co-stimulatory events in T-lymphocytes. The data support a differential adhesive rather than a co-stimulatory role of CD26 in muscle-invasive cells. The adaptability of the NCDS algorithm to diverse types of cells should enable us to approach any invasion process, including invasion of malignant cells.

scholarly journals Preservation of active incretin hormones by inhibition of dipeptidyl peptidase IV suppresses meal-induced incretin secretion in dogs

2002 ◽  
Vol 172 (2) ◽  
pp. 355-362 ◽  
Author(s):  
CF Deacon ◽  
S Wamberg ◽  
P Bie ◽  
TE Hughes ◽  
JJ Holst
Keyword(s):  
Plasma Concentrations ◽  
Dipeptidyl Peptidase ◽  
Feedback Mechanism ◽  
Dipeptidyl Peptidase Iv ◽  
Biologically Active ◽  
Incretin Hormones ◽  
Dpp Iv ◽  
Incretin Secretion ◽  
Glucagon Like Peptide 1

The incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are degraded by dipeptidyl peptidase IV (DPP IV), thereby losing insulinotropic activity. DPP IV inhibition reduces exogenous GLP-1 degradation, but the extent of endogenous incretin protection has not been fully assessed, largely because suitable assays which distinguish between intact and degraded peptides have been unavailable. Using newly developed assays for intact GLP-1 and GIP, the effect of DPP IV inhibition on incretin hormone metabolism was examined. Conscious dogs were given NVP-DPP728, a specific DPP IV inhibitor, at a dose that inhibited over 90% of plasma DPP IV for the first 90 min following treatment. Total and intact incretin concentrations increased (P<0.0001) following a mixed meal, but on control days (vehicle infusion), intact peptide concentrations were lower (P<0.01) than total peptide concentrations (22.6 +/- 1.2% intact GIP; 10.1 +/- 0.4% intact GLP-1). Following inhibitor treatment, the proportion of intact peptide increased (92.5 +/- 4.3% intact GIP, P<0.0001; 99.0 +/- 22.6% intact GLP-1, P<0.02). Active (intact) incretins increased after NVP-DPP728 (from 4797 +/- 364 to 10 649 +/- 106 pM x min for GIP, P<0.03; from 646 +/- 134 to 2822 +/- 528 pM x m in for GLP-1, P<0.05). In contrast, total incretins fell (from 21 632 +/- 654 to 12 084 +/- 1723 pM x min for GIP, P<0.002; from 5145 +/- 677 to 3060 +/- 601 pM x min for GLP-1, P<0.05). Plasma glucose, insulin and glucagon concentrations were unaltered by the inhibitor. We have concluded that DPP IV inhibition with NVP-DPP728 prevents N-terminal degradation of endogenous incretins in vivo, resulting in increased plasma concentrations of intact, biologically active GIP and GLP-1. Total incretin secretion was reduced by DPP IV inhibition, suggesting the possibility of a feedback mechanism.

Cleavage by CD26/dipeptidyl peptidase IV converts the chemokine LD78β into a most efficient monocyte attractant and CCR1 agonist

Blood ◽  
2000 ◽  
Vol 96 (5) ◽  
pp. 1674-1680 ◽  
Author(s):  
Paul Proost ◽  
Patricia Menten ◽  
Sofie Struyf ◽  
Evemie Schutyser ◽  
Ingrid De Meester ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Specific Activity ◽  
High Capacity ◽  
Dipeptidyl Peptidase ◽  
Dipeptidyl Peptidase Iv ◽  
Surface Glycoprotein ◽  
Peripheral Blood Mononuclear ◽  
Dpp Iv ◽  
Stromal Cell Derived Factor ◽  
Hiv 1

Abstract Chemokines are proinflammatory cytokines that play a role in leukocyte migration and activation. Recent reports showed that RANTES (regulated on activation normal T-cell expressed and secreted chemokine), eotaxin, macrophage-derived chemokine (MDC), and stromal cell–derived factor-1 (SDF-1) are NH2-terminally truncated by the lymphocyte surface glycoprotein and protease CD26/dipeptidyl peptidase IV (CD26/DPP IV). Removal of the NH2-terminal dipeptide resulted in impaired inflammatory properties of RANTES, eotaxin, MDC, and SDF-1. The potential CD26/DPP IV substrate macrophage inflammatory protein–1β (MIP-1β) and the related chemokine, LD78α (ie, one of the MIP-1α isoforms), were not affected by this protease. However, CD26/DPP IV cleaved LD78β, a most potent CCR5 binding chemokine and inhibitor of macrophage tropic human immunodeficiency virus–1 (HIV-1) infection, into LD78β(3-70). Naturally truncated LD78β(3-70), but not truncated MIP-1β, was recovered as an abundant chemokine form from peripheral blood mononuclear cells. In contrast to all other chemokines processed by CD26/DPP IV, LD78β(3-70) had increased chemotactic activity in comparison to intact LD78β. With a minimal effective concentration of 30 pmol/L, LD78β(3-70) became the most efficient monocyte chemoattractant. LD78β(3-70) retained its high capacity to induce an intracellular calcium increase in CCR5-transfected cells. Moreover, on CCR1 transfectants, truncated LD78β(3-70) was 30-fold more potent than intact LD78β. Thus, CD26/DPP IV can exert not only a negative but also a positive feedback during inflammation by increasing the specific activity of LD78β. CD26/DPP IV–cleaved LD78β(3-70) is the most potent CCR1 and CCR5 agonist that retains strong anti–HIV-1 activity, indicating the importance of the chemokine-protease interaction in normal and pathologic conditions.

scholarly journals Evidence for a role of dipeptidyl peptidase IV in fibronectin-mediated interactions of hepatocytes with extracellular matrix

1989 ◽  
Vol 262 (1) ◽  
pp. 327-334 ◽  
Author(s):  
G A Piazza ◽  
H M Callanan ◽  
J Mowery ◽  
D C Hixson
Keyword(s):  
Extracellular Matrix ◽  
Cell Surface ◽  
Rat Liver ◽  
Tissue Transglutaminase ◽  
Dipeptidyl Peptidase ◽  
Dipeptidyl Peptidase Iv ◽  
Type I ◽  
Cell Surface Glycoprotein ◽  
Dpp Iv ◽  
Fibronectin Binding

Dipeptidyl peptidase IV (DPP IV) is a cell surface glycoprotein which has been implicated in hepatocyte-extracellular matrix interactions [Hixson, DeLourdes, Ponce, Allison & Walborg (1984) Exp. Cell Res. 152, 402-414; Walborg, Tsuchida, Weeden, Thomas, Barrick, McEntire, Allison & Hixson (1985) Exp. Cell Res. 158, 509-518; Hanski, Huhle & Reutter (1985) Biol. Chem. Hoppe-Seyler 366, 1169-1176]. However, its proteolytic substrate(s) and/or binding protein(s) which mediate this influence have not been conclusively identified. Nitrocellulose binding assays using 125I-labelled DPP IV that was purified to homogeneity from rat hepatocytes revealed a direct interaction of DPP IV with fibronectin. Although fibronectin could mediate an indirect binding of DPP IV to collagen, no evidence was found for a direct binding of DPP IV to native or denatured Type I collagen. Fibronectin appeared to bind DPP IV at a site distinct from its exopeptidase substrate recognition site since protease inhibitors such as competitive peptide substrates and phenylmethanesulphonyl fluoride enhanced binding, possibly as a result of an altered conformation of DPP IV. To determine if fibronectin binding to DPP IV is involved in the interaction of fibronectin with the hepatocyte surface, the effect of various DPP IV inhibitors on 125I-fibronectin binding to isolated hepatocytes in suspension was examined. Kinetic studies revealed that inhibitors of DPP IV which enhanced fibronectin binding in vitro accelerated the initial binding of fibronectin to the cell surface where it was subsequently cross-linked (presumably by tissue transglutaminase) to as yet undefined components. Immunolocalization of fibronectin and DPP IV in normal rat liver sections showed that both proteins were present along the hepatocyte sinusoidal membrane. These observations, coupled with previous results showing that DPP IV is tightly bound to biomatrix isolated from rat liver (Hixson et al., 1984; Walborg et al., 1985), suggest that DPP IV binding to fibronectin may play a role in interactions of hepatocytes with extracellular matrix in vivo and possibly in matrix assembly.

Detection of dipeptidyl peptidase IV in glioma C6 and neuroblastoma SK-N-SH cell lines

1995 ◽  
Vol 73 (1-2) ◽  
pp. 113-115 ◽  
Author(s):  
Aleksi Sedo ◽  
Roberto P. Revoltella
Keyword(s):  
Cell Surface ◽  
Cell Line ◽  
Cell Lines ◽  
Neuroblastoma Cell ◽  
Dipeptidyl Peptidase ◽  
Dipeptidyl Peptidase Iv ◽  
Human Neuroblastoma Cell ◽  
Fluorescent Substrate ◽  
Human Neuroblastoma ◽  
Dpp Iv

The dipeptidyl peptidase IV (DPP-IV) activity of the rat glioma cell line C6 and the human neuroblastoma cell line SK-N-SH was investigated. DPP-IV fluorescent substrate was cleaved by both cell lines. The pH reaction optimum determined was typical for DPP-IV described in other cell models. The reaction was inhibited by specific inhibitors diprotins A and B. Enzyme activity was localized, both on the cell surface and intracellularly. Most of the DPP-IV activity was membrane bound. However, soluble intra-cellular activity was found in both cell lines. Secreted activity was not detected in either cell line. In the C6 line, but not in the SK-N-SH line, we demonstrated depression of the ratio of cell surface to total cell DPP-IV activity at higher cell densities, indicating possible enzyme redistribution during cell growth in culture. Identification of DPP-IV activity is the first step in our study of the role of DPP-IV in the neural system.Key words: dipeptidyl peptidase IV, glioma, neuroblastoma.

Cleavage by CD26/dipeptidyl peptidase IV converts the chemokine LD78β into a most efficient monocyte attractant and CCR1 agonist

Blood ◽  
2000 ◽  
Vol 96 (5) ◽  
pp. 1674-1680 ◽  
Author(s):  
Paul Proost ◽  
Patricia Menten ◽  
Sofie Struyf ◽  
Evemie Schutyser ◽  
Ingrid De Meester ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Specific Activity ◽  
High Capacity ◽  
Dipeptidyl Peptidase ◽  
Dipeptidyl Peptidase Iv ◽  
Surface Glycoprotein ◽  
Peripheral Blood Mononuclear ◽  
Dpp Iv ◽  
Stromal Cell Derived Factor ◽  
Hiv 1

Chemokines are proinflammatory cytokines that play a role in leukocyte migration and activation. Recent reports showed that RANTES (regulated on activation normal T-cell expressed and secreted chemokine), eotaxin, macrophage-derived chemokine (MDC), and stromal cell–derived factor-1 (SDF-1) are NH2-terminally truncated by the lymphocyte surface glycoprotein and protease CD26/dipeptidyl peptidase IV (CD26/DPP IV). Removal of the NH2-terminal dipeptide resulted in impaired inflammatory properties of RANTES, eotaxin, MDC, and SDF-1. The potential CD26/DPP IV substrate macrophage inflammatory protein–1β (MIP-1β) and the related chemokine, LD78α (ie, one of the MIP-1α isoforms), were not affected by this protease. However, CD26/DPP IV cleaved LD78β, a most potent CCR5 binding chemokine and inhibitor of macrophage tropic human immunodeficiency virus–1 (HIV-1) infection, into LD78β(3-70). Naturally truncated LD78β(3-70), but not truncated MIP-1β, was recovered as an abundant chemokine form from peripheral blood mononuclear cells. In contrast to all other chemokines processed by CD26/DPP IV, LD78β(3-70) had increased chemotactic activity in comparison to intact LD78β. With a minimal effective concentration of 30 pmol/L, LD78β(3-70) became the most efficient monocyte chemoattractant. LD78β(3-70) retained its high capacity to induce an intracellular calcium increase in CCR5-transfected cells. Moreover, on CCR1 transfectants, truncated LD78β(3-70) was 30-fold more potent than intact LD78β. Thus, CD26/DPP IV can exert not only a negative but also a positive feedback during inflammation by increasing the specific activity of LD78β. CD26/DPP IV–cleaved LD78β(3-70) is the most potent CCR1 and CCR5 agonist that retains strong anti–HIV-1 activity, indicating the importance of the chemokine-protease interaction in normal and pathologic conditions.

Dipeptidyl Peptidase IV Inhibitors for Nonalcoholic Fatty Liver Disease – Systematic Review and Metanalysis

2020 ◽  
Vol 16 ◽  
Author(s):  
Lucas Ribeiro dos Santos ◽  
Marcio Luis Duarte ◽  
Maria Stella Peccin ◽  
Antônio Ricardo de Toledo Gagliardi ◽  
Tamara Melnik
Keyword(s):  
Hepatic Steatosis ◽  
Grey Literature ◽  
Specific Treatment ◽  
Reducing Power ◽  
Dipeptidyl Peptidase ◽  
Dipeptidyl Peptidase Iv ◽  
Cochrane Library ◽  
Vast Number ◽  
Dpp Iv ◽  
Dipeptidyl Peptidase Iv Inhibitors

Introduction:: Hepatic steatosis is a frequent condition, that afflicts, especially, obese and insulin resistant patients; diagnosis is made, usually, through imaging tests. Despite the high prevalence and risk of complications, there is no specific treatment approved, though a vast number of medications have been tested. Objective:: To determine the efficacy of dipeptidyl peptidase IV inhibitors (i DPP-IV) in the treatment of NAFLD. Methods:: We searched the electronic databases of the Cochrane Library, MEDLINE, EMBASE and LILACS, as well as reference lists of the included studies and grey literature; 9 studies were selected for inclusion. Results:: 7 studies were used for metanalysis, for 3 outcomes. i DPP-IV showed an ALT-reducing power of MD -10.83 [95% CI 35.23 to 13.57] at 3 months and MD -9.27 [95% CI 10.92 to -7.62] at 6 months of intervention, as well as reduction of hepatic steatosis via MRI of SMD 0.10 [95% CI 0.31 to 0.50]; the overall incidence of adverse events was very low. The studies were considered of low and very low quality by the GRADE evaluation. Conclusion:: Because of the poor overall quality of the studies and heterogeneity of the population analyzed, i DPP-IV did not show efficacy on inflammatory markers or fibrosis in patients with NAFLD.

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