Search results for "Dipeptidyl peptidase"
showing 10 items of 31 documents
External-beam radiotherapy as preparative regimen for hepatocyte transplantation after partial hepatectomy
2006
Purpose: The transplantation of donor hepatocytes is considered a promising option to correct chronic liver failure through repopulation of the diseased organ. This study describes a novel selective external-beam irradiation technique as a preparative regimen for hepatocyte transplantation. Methods and Materials: Livers of dipeptidylpeptidase IV (DPPIV)–deficient rats were preconditioned with external-beam single-dose irradiation (25 Gy) delivered to two thirds of the liver. Four days later, a one-third partial hepatectomy (PH) was performed to resect the untreated liver section, and 15 million wild-type (DPPIV + ) hepatocytes were transplanted via the spleen into the recipient livers. The …
The protease complex consisting of dipeptidyl peptidase IV and seprase plays a role in the migration and invasion of human endothelial cells in colla…
2006
Abstract Dipeptidyl peptidase IV (DPP4/CD26) and seprase/fibroblast activation protein α are homologous type II transmembrane, homodimeric glycoproteins that exhibit unique prolyl peptidase activities. Human DPP4 is ubiquitously expressed in epithelial and endothelial cells and serves multiple functions in cleaving the penultimate positioned prolyl bonds at the NH2 terminus of a variety of physiologically important peptides in the circulation. Recent studies showed a linkage between DPP4 and down-regulation of certain chemokines and mitogenic growth factors, and degradation of denatured collagens (gelatin), suggesting a role of DPP4 in the cell invasive phenotype. Here, we found the existen…
Fractionated External Beam Radiotherapy as a Suitable Preparative Regimen for Hepatocyte Transplantation After Partial Hepatectomy
2010
Purpose Hepatocyte transplantation is strongly considered to be a promising option to correct chronic liver failure through repopulation of the diseased organ. We already reported on extensive liver repopulation by hepatocytes transplanted into rats preconditioned with 25-Gy single dose selective external beam irradiation (IR). Herein, we tested lower radiation doses and fractionated protocols, which would be applicable in clinical use. Methods and Material Livers of dipeptidylpeptidase IV (DPPIV)-deficient rats were preconditioned with partial liver external beam single dose IR at 25 Gy, 8 Gy, or 5 Gy, or fractionated IR at 5 × 5 Gy or 5 × 2 Gy. Four days after completion of IR, a partial …
Comparison of DPP‐4 inhibition versus GLP‐1 analogue supplementation on survival and vascular complications in experimental sepsis (145.2)
2014
Background: Dipeptidyl peptidase [DPP]-4 inhibitors are a new class of drug for the treatment of hyperglycemia and recent studies revealed anti-inflammatory effects of these gliptins in experimenta...
Modulation of Diabetes by Natural Products and Medicinal Plants via Incretins
2019
Incretins are metabolic hormones released after a meal that increase insulin secretion from pancreatic β-cells. The two main incretins are the intestinal peptides glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide. Both induce a decrease in glycemia, slow down the absorption of nutrients, and are inactivated by the enzyme dipeptidyl peptidase-4. Recently, incretin-based therapies have become a useful tool to treat diabetic patients, and different studies have focused on the identification of glucagon-like peptide-1 receptor agonists, including those of natural origin. This review focuses on the new findings of medicinal plants and natural products as possible active ag…
Ammonium formate-Pd/C as a new reducing system for 1,2,4-oxadiazoles. Synthesis of guanidine derivatives and reductive rearrangement to quinazolin-4-…
2021
1,2,4-Oxadiazole is a heterocycle with wide reactivity and many useful applications. The reactive O-N bond is usually reduced using molecular hydrogen to obtain amidine derivatives. NH4CO2H-Pd/C is here demonstrated as a new system for the O-N reduction, allowing us to obtain differently substituted acylamidine, acylguanidine and diacylguanidine derivatives. The proposed system is also effective for the achievement of a reductive rearrangement of 5-(2′-aminophenyl)-1,2,4-oxadiazoles into 1-alkylquinazolin-4(1H)-ones. The alkaloid glycosine was also obtained with this method. The obtained compounds were preliminarily tested for their biological activity in terms of their cytotoxicity, induce…
Association between use of novel glucose-lowering drugs and COVID-19 hospitalization and death in patients with type 2 diabetes: a nationwide registr…
2022
Abstract Aims Type 2 diabetes (T2DM) in patients with coronavirus disease-19 (COVID-19) is associated with a worse prognosis. We separately investigated the associations between the use of sodium-glucose cotransporter 2 inhibitors (SGLT2i), glucagon-like peptide-1 receptor agonists (GLP-1 RA), and dipeptidyl peptidase-4 inhibitors (DPP-4i), and the risk of COVID-19 hospitalization and death. Methods and results Patients with T2DM registered in the Swedish National Patient Registry and alive on 1 February 2020 were included. ‘Incident severe COVID-19’ was defined as the first hospitalization and/or death from COVID-19. A modified Poisson regression approach was applied to a 1:1 propensity sc…
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…
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…
The SGLT2 inhibitor empagliflozin improves the primary diabetic complications in ZDF rats
2017
Hyperglycemia associated with inflammation and oxidative stress is a major cause of vascular dysfunction and cardiovascular disease in diabetes. Recent data reports that a selective sodium-glucose co-transporter 2 inhibitor (SGLT2i), empagliflozin (Jardiance®), ameliorates glucotoxicity via excretion of excess glucose in urine (glucosuria) and significantly improves cardiovascular mortality in type 2 diabetes mellitus (T2DM). The overarching hypothesis is that hyperglycemia and glucotoxicity are upstream of all other complications seen in diabetes. The aim of this study was to investigate effects of empagliflozin on glucotoxicity, β-cell function, inflammation, oxidative stress and endothel…