Evaluation of proteolytic activity and serine proteases distribution in plasma from patients with bladder cancer

BackgroundBladder cancer (BC) is an aggressive disease with a poor prognosis. A bladder tumor, like other malignant neoplasms, is characterized by the presence of both cancer cells and stromal cells which secrete cytokines, chemokines, growth factors, and proteolytic enzymes. One such class of proteolytic enzymes are serine proteases, which take part in the tumor microenvironment formation via supporting and contributing to tumor progression. This study aims to evaluate the proteolytic activity and serine protease contribution in plasma from BC patients.MethodsThe research involved patients of Alexandrovsky city clinical hospital aged 52–76 with transitional cell carcinoma of the bladder. All examined patients were divided into five groups: the control group included conditionally healthy donors, while other patients were grouped according to their tumor stage (I, II, III and IV). Plasma plasminogen levels were determined by enzyme-linked immunosorbent assay, and the potential activity was measured by chromogenic plasminogen assay. Serine proteases fractions were obtained by the affinity chromatography method, and enzyme concentration in the selected fractions were determined by the Bradford method. Serine proteases distribution was investigated by electrophoresis in a polyacrylamide gel.ResultsIt was determined that the concentration, potential activity of plasminogen, and the total amount of serine proteases in plasma from BC patients were greater than the values of the corresponding indicators in healthy donors. This could be one of the factors contributing to increased proteolysis seen in the process of carcinogenesis. Plasminogen concentration in BC patients with stage IV disease; however, displayed a tendency to be reduced compared to earlier stages, and the potential activity of plasminogen was significantly lower in patients with stages III – IV BC. Futhermore, a tumor stage specific gradual decline in the serine protease plasma content was shown. The results of electrophoretic analysis established a significant diminishment in the percentage of high molecular weight components (under non-reducing conditions) and their complete disappearance (under reducing conditions) in plasma serine protease fractions from BC patients. A decline in the percentage of heavy and light plasmin chains in BC patients was also observed. Additionally, a rise in the degraded forms of plasminogen/plasmin content was seen in BC samples, as well as the presence of fractions corresponding to trypsin and NE (under non-reducing conditions) that were absent in the control samples.ConclusionThe results indicate significant changes in the proteolytic activity of plasma, from BC patients when compared to healthy controls, which is accompanied by alterations in serine protease distribution caused by tumor microenvironment pecularlities at the different stages of oncopathology

Disturbances of extracellular protein metabolism in ceruleininduced pancreatitis

Chronic pancreatitis (CP) is still a serious clinical problem due to the significant difficulties in its diagnosis, especially in the initial stages of development. Among the mechanisms that mediate the pathogenesis of CP and lead to pancreatitis-related disorders is unregulated activation of proteolytic enzymes, namely, matrix metalloproteinases (MMPs). The aim of our study was to determine the disturbances of protein metabolism under the conditions of CP alone or in combination with diabetes type 1 (CP+DT1). Herein, CP was induced in the nonlinear male rats by intraperitoneal injection of cerulein (5 µg·kg−1 of body weight; five times during fives day). DT1 was modeled in the rats with CP by a single intraperitoneal injection of streptozotocin (65 mg·kg−1 of the body weight). The levels of MMP-2 and -9 were determined by enzyme-linked immune sorbent assay, and the level of low and middle molecular weight (LMMW) substance was measured spectrophotometrically, while the peptide fractions were analyzed by size exclusion chromatography. The present study revealed a significant increase of MMP-2 and MMP-9 levels in the serum, liver and pancreas of the rats with CP and CP+DT1. Elevated levels of MMPS may act as a factor for the initiation of subsequent cascade of events resulting in the development of pancreatitis-associated complications. Pathogenesis of chronic pancreatitis alone or in combination with diabetes type 1 has been accompanied by the formation and accumulation of LMMW substance, changes in peptide composition and level of individual peptides in the tissues of the rats. Such alterations are among key triggers of amplification of metabolic disorders under chronic pancreatitis

Prevention of diet-induced obesity in rats by oral application of collagen fragments

The aim of the present study was to determine whether orally applied collagen fragments (CFs) could affect the development of obesity in obese rats. To this end, experimental rats that were exposed to a high-calorie diet (HCD) for four weeks were randomly divided into two groups: HCD and HCD+CFs, with both groups continuing to receive the HCD. However, rats from the HCD+CFs group were also provided with CFs in a 0.05-M citrate buffer (pH 5.0) (1 g·kg-1 of body weight) by intragastric administration, every other day for the next six weeks. Selected parameters associated with obesity development and insulin resistance, as well as serum markers of oxidative stress and the cytokine profile were assessed at the end of the 10th week. Supplementation with CFs resulted in a decrease in body weight and body mass index when compared to animals exposed to a HCD. The observed changes were assumed to be caused by a lower food intake and increased water intake by obese rats treated with CFs. Enhanced activity of superoxide dismutase (SOD), catalase (CAT) and decreased malondialdehyde (MDA) concentration were detected in the HCD+CF group of animals when compared to untreated HCD-fed rats. Administration of CFs also lowered the serum concentrations of the proinflammatory cytokines IL-1β and IL-12, whereas the concentration of the anti-inflammatory cytokine IL-10 was significantly increased and the concentration of cytokine IL-4 was near the control value. Decreased concentrations of fasting blood glucose, glycated hemoglobin (GHbA1c) and serum insulin and increased tolerance to glucose in the oral glucose tolerance test (OGTT) were observed in the HCD+CF group of animals when compared to rats in the HCD group. We concluded that CFs mediated a therapeutic effect on obesity development in rats exposed to a HCD by affecting pathways involved in obesity pathogenesis

Effect of Peptides from Plasma of Patients with Coronary Artery Disease on the Vascular Endothelial Cells

Background and Objectives: Coronary artery disease (CAD) is the foremost cause of adult disability and mortality. There is an urgent need to focus on the research of new approaches for the prevention and treatment of CAD. Materials and Methods: The effects of peptides isolated from the blood plasma of CAD patients on endothelial cell secretion using the in vitro model have been tested. Human endothelial progenitor cells (HEPCs) were incubated for 24 h with peptides isolated from the plasma of healthy subjects or patients with stable angina, progressive unstable angina, and myocardial infarction. The contents of some soluble anticoagulant as well as procoagulant mediators in HEPC culture treated with peptide pools were then compared. Results and Conclusion: The results show that peptides from the plasma of patients with myocardial infarction promote endothelial cells to release both von Willebrand factor and endothelin-1, increasing vasoconstriction and shifting hemostatic balance toward a prothrombotic state. In contrast, peptides from the plasma of patients with progressive unstable angina suppress the secretion of endothelin-1 by HEPCs, while the secretion of both von Willebrand factor and tissue plasminogen activator was increased. As can be seen from the results obtained, disease derived peptides may contribute to the homeostasis of living organisms or the progression of pathological processes

Effect of Peptides from Plasma of Patients with Coronary Artery Disease on the Vascular Endothelial Cells

Background and Objectives: Coronary artery disease (CAD) is the foremost cause of adult disability and mortality. There is an urgent need to focus on the research of new approaches for the prevention and treatment of CAD. Materials and Methods: The effects of peptides isolated from the blood plasma of CAD patients on endothelial cell secretion using the in vitro model have been tested. Human endothelial progenitor cells (HEPCs) were incubated for 24 h with peptides isolated from the plasma of healthy subjects or patients with stable angina, progressive unstable angina, and myocardial infarction. The contents of some soluble anticoagulant as well as procoagulant mediators in HEPC culture treated with peptide pools were then compared. Results and Conclusion: The results show that peptides from the plasma of patients with myocardial infarction promote endothelial cells to release both von Willebrand factor and endothelin-1, increasing vasoconstriction and shifting hemostatic balance toward a prothrombotic state. In contrast, peptides from the plasma of patients with progressive unstable angina suppress the secretion of endothelin-1 by HEPCs, while the secretion of both von Willebrand factor and tissue plasminogen activator was increased. As can be seen from the results obtained, disease derived peptides may contribute to the homeostasis of living organisms or the progression of pathological processes

Erneuerbare Energien im Verkehr Potenziale und Entwicklungsperspektiven verschiedener erneuerbarer Energieträger und Energieverbrauch der Verkehrsträger

Mit dem Ziel einen Debattenbeitrag zur Frage "Was wäre, wenn der Verkehr der Zukunft auf Erneuerbaren Energien basieren würde?", zu leisten, werden in der Studie "Erneuerbare Energien im Verkehr" technische Potenziale erneuerbarer Energieträger in Deutschland ermittelt und verschiedenen Szenarien zum Energieverbrauch des Verkehrssektors bis zum Jahr 2050 gegenübergestellt. Die Ergebnisse erlauben es, ein erstes umfassendes Bild vom erwarteten Energieverbrauch des Verkehrs und den Potenzialen geeigneter erneuerbarer Energieträger zu geben