Proteolytic Activity Of Plasma Research Articles

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

Bladder 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. The 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. It 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. The 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.

Analysis of the condition of the kallikrein-kinin system in the comorbid course of chronic pancreatitis and type 2 diabetes

Background. According to evidence, within approximately 8 years, 50% of patients with chronic pancreatitis (CP) develop endocrine and exocrine insufficiency, which manifests itself as steatorrhea, weight loss, diabetes mellitus (DM), and nutritional disorders. Diabetes mellitus aggravates these phenomena, which deepens the disorder of metabolic processes in CP, including protein metabolism. Protein structures include components of the kallikrein-kinin system (KKS), which plays a role in the regulation of vascular tone, diuresis, inflammation, coagulation, and pain reception. Due to repeated exacerbations of pancreatitis, there is fibrosis of the pancreas, which increases the risk of insulin resistance and the formation of type 2 diabetes. Thus, disorders of the kallikrein-kinin system and the progression of CP are interrelated, which makes it important to study the state of KKS in CP, especially in combination with type 2 diabetes mellitus. The purpose is to investigate the state of the kallikrein-kinin system in chronic pancreatitis in outpatients, depending on the presence of concomitant type 2 diabetes. Material and methods. 137 outpatients with CP with concomitant diabetes mellitus and without diabetes were studied: the main group— 112 patients with CP without exacerbation in combination with diabetes mellitus in a state of complete or subcompensation, and the comparison group— 25 patients with isolated CP. Evaluation of general and specific proteolysis (α1-proteinase inhibitor, α2-macroglobulin, kallikrein, kininase II activity, prekallikrein, plasma proteolytic activity) was performed by the method analysis using standard kits from BIOSERV ELISA. Results. There was a 20.8% increase in the level of the total proteolytic activity of plasma in the group of patients with comorbidity of CP and diabetes mellitus compared with the group with isolated CP, 51.9% increase in specific proteolysis (or kininogenesis)— the level of kallikrein (proteolysis enzyme), p<0.05. At the same time, a decrease in prekallikrein (inactive precursor of kallikrein) was found in the group of patients with comorbidity by 19.4% compared to that in isolated CP (p < 0.05). The presence of dissociation of protective parameters of kallikrein-kinin system is proved; increase by 9.4% of α1-proteinase inhibitor content at comorbidity of CP and DM2 in relation to that in isolated CP; decrease in the content of α2-macroglobulin in CP relative to the control group (p<0.05), which showed a decrease in the body’s compensatory capacity in CP, at the same time found an increase in α2-macroglobulin in the comorbidity of CP with DM2 by 49.5% relative to isolated CP; reduction of kininase-II activity in CP and diabetes mellitus by 14.5% relative to that in CP. Conclusions. Activation of KKS with multidirectional changes in KKS parameters and general and specific proteolysis in CP was noted. In CP and in the comorbid course with diabetes mellitus, further activation of proteolysis took place with the simultaneous inclusion of protective mechanisms for resolving inflammation and detoxification. Excessive production of kinins in concomitant DM2 has been proven, which weakened the body’s protective response.

Correction of murine ADAMTS13 deficiency by hematopoietic progenitor cell–mediated gene therapy

AbstractADAMTS13, a metalloprotease primarily synthesized in liver and endothelial cells, cleaves von Willebrand factor (VWF) at the central A2 domain, thereby reducing the sizes of circulating VWF multimers. Genetic or acquired deficiency of plasma ADAMTS13 activity leads to a potentially fatal syndrome, thrombotic thrombocytopenic purpura (TTP). To date, plasma infusion or exchange is the only proven effective therapy for TTP. In search for a better therapy, an autologous transplantation of hematopoietic progenitor cells transduced ex vivo with a self-inactivating lentiviral vector encoding a full-length murine Adamts13 and an enhanced green fluorescent protein (GFP) reporter gene was performed in Adamts13−/− mice after irradiation. All recipient mice showed detectable ADAMTS13 antigen and proteolytic activity in plasma despite only low levels of bone marrow chimerism. The levels of plasma ADAMTS13 were sufficient to eliminate the ultralarge VWF multimers and offered systemic protection against ferric chloride–induced arterial thrombosis. The data suggest that hematopoietic progenitor cells can be genetically modified ex vivo and transplanted in an autologous model to provide adequate levels of functional ADAMTS13 metalloprotease. This success may provide the basis for development of a novel therapeutic strategy to cure hereditary TTP in humans.

Correction of ADAMTS13 Deficiency by In Utero Gene Transfer of Lentiviral Vector encoding ADAMTS13 Genes

Deficiency of A Disintegrin And Metalloprotease with ThromboSpondin (ADAMTS13) results in thrombotic thrombocytopenic purpura (TTP). Plasma infusion or exchange is the only effective treatment to date. We show in this study that an administration of a self-inactivating lentiviral vector encoding human full-length ADAMTS13 and a variant truncated after the spacer domain (MDTCS) in mice by in utero injection at embryonic days 8 and 14 resulted in detectable plasma proteolytic activity (approximately 5-70%), which persisted for the length of the study (up to 24 weeks). Intravascular injection via a vitelline vein at E14 was associated with significantly lower rate of fetal loss than intra-amniotic injection, suggesting that the administration of vector at E14 may be a preferred gestational age for vector delivery. The mice expressing ADAMTS13 and MDTCS exhibited reduced sizes of von Willebrand factor (vWF) compared to the Adamts13(-/-) mice expressing enhanced green fluorescent protein (eGFP). Moreover, the mice expressing both ADAMTS13 and MDTCS showed a significant prolongation of ferric chloride-induced carotid arterial occlusion time as compared to the Adamts13(-/-) expressing eGFP. The data demonstrate the successful correction of the prothrombotic phenotypes in Adamts13(-/-) mice by a single in utero injection of lentiviral vectors encoding human ADAMTS13 genes, providing the basis for developing a gene therapy for hereditary TTP in humans.

Phenotypic Correction of Adamts13-Deficient Mice by Early Intra-Amniotic Gene Transfer of Lentiviral Vector Encoding ADAMTS13 Genes.

ADAMTS13, a member of A Disintegrin and Metalloprotease with ThromboSpondin type 1 repeats (ADAMTS) family, is mainly synthesized in the hepatic stellate cells, endothelial cells and megakaryocytes or platelets. It controls the sizes of von Willebrand factor (VWF) multimers by cleaving VWF at the Tyr1605-Met1606 bond. Genetic deficiency of plasma ADAMTS13 activity results in hereditary thrombotic thrombocytopenic purpura (TTP), also named Upshaw-Schülman syndrome. To develop a potential gene therapy approach and to determine the domains of ADAMTS13 required for recognition and cleavage of VWF in vivo, a self-inactivating lentiviral vector encoding human wild-type ADAMTS13 or variant truncated after the spacer domain (construct MDTCS) was administrated by intra-amniotic injection on embryonic day 8. Direct stereomicroscopy and immunofluorescent microscopic analysis revealed that the green fluorescent protein (GFP) reporter, ADAMTS13 and MDTCS were predominantly expressed in the heart, kidneys and skin. The synthesized ADAMTS13 and truncated variant were detectable in mouse plasma by immunoprecipitation and Western blot, as well as by proteolytic cleavage of FRETS-VWF73 substrate. The levels of proteolytic activity in plasma of mice expressing ADAMTS13 and MDTCS were 5 ± 7% and 60 ± 70%, respectively using normal human plasma as a standard, and this proteolytic activity persisted for at least 24 weeks in Adamts13−/−mice and 42 weeks in wild-type mice tested (the duration of observation). The mice expressing both recombinant ADAMTS13 and MDTCS showed a significantly decreased ratio of plasma VWF collagen-binding activity to antigen and a reduction in VWF multimer sizes as compared to those in the controls. Moreover, the mice expressing ADAMTS13 and MDTCS showed a significant prolongation of ferric chloride-induced carotid arterial occlusion time (9.0 ± 0.6 and 25.2 ± 3.2 min, respectively) as compared to the Adamts13−/− mice expressing GFP alone (5.6 ± 0.5 min) (p<0.01). The ferric chloride-induced carotid occlusion time in Adamts13−/− mice expressing ADAMTS13 was almost identical to that in wild type mice with same genetic background (C56BL/6) (8.0 ± 0.2 min) (p>0.05). The data demonstrate the correction of the prothrombotic phenotype in Adamts13−/−mice by gene transfer to the fetus by viral vectors encoding human wild type ADAMTS13 and the carboxyl terminal truncated variant (MDTCS), supporting the feasibility of developing a gene therapy based treatment for hereditary TTP. The discrepancy in the proteolytic activity of MDTCS between in vitro (Zhang P et al. Blood, 2007 in press) and in vivo in the present study suggests the potential cofactors in murine circulation that may rescue the defective proteolytic activity of the carboxyl-terminal truncated ADAMTS13 protease seen in vitro.

Effective Treatment of Gut Barrier Dysfunction Using an Antioxidant, a PAF Inhibitor, and Monoclonal Antibodies against the Adhesion Molecule PECAM-1

Background. Oxygen free radicals (OFRs), platelet activating factor (PAF), cell adhesion molecules, and transmigration of polymorphonuclear leukocytes through the gut barrier are probably all essential in the development of gut barrier dysfunction following intestinal ischemia and reperfusion (I/R). Pretreatment and early treatment of I/R with the OFRs-scavenger (NAC), the PAF inhibitor lexipafant, and monoclonal antibodies against the adhesion molecule PECAM-1 (anti-PECAM-1-Mab) have been reported to be effective in the prevention or recovery of gut barrier dysfunction and result in a decrease in cytokine levels. Less is known about the effect of treatment inserted during the late stage of I/R. The objective of this study was to evaluate the potential therapeutic value of single or combination therapy with NAC, lexipafant, and anti-PECAM-1-MAb administered late during intestinal I/R in the rat.Methods. NAC, lexipafant, and anti-PECAM-1-MAb were administrated, alone or in combination, after 3 h of reperfusion following 40 min of superior mesenteric arterial ischemia in the rat. Intestinal endothelial and epithelial barrier permeability, myeloperoxidase (MPO) activity, interleukin-1β (IL-1β), and protease inhibitor levels were evaluated after 12 h of reperfusion.Results. Intestinal endothelial and epithelial permeability significantly increased in rats with I/R and saline treatment. Proteolytic activity in plasma was indicated by low levels of the three measured plasma protease inhibitors. Intestinal mucosal MPO content increased significantly. These changes were, to different degrees, reduced by late inserted treatment with NAC, lexipafant, or anti-PECAM-1-MAb. Alterations in systemic levels of IL-1β paralleled the changes found in gut barrier permeability and leukocyte trapping. Systemic antithrombin III levels and increased barrier permeability in remote organs were partly restored, especially by multimodal therapy.Conclusion. Treatment with NAC, lexipafant, and/or monoclonal antibodies against PECAM-1, inserted at a later stage of I/R, reduced the severity of I/R-associated intestinal dysfunction and decreased the systemic concentrations of IL-1β, local leukocyte recruitment (MPO), and partly restored plasma protease inhibitor levels.

Effects of inhibition of PAF, ICAM-1 and PECAM-1 on gut barrier failure caused by intestinal ischemia and reperfusion.

The role of cell adhesion molecules and transmigration of PMNs through the endothelial barrier is probably essential in intestinal ischemia and reperfusion (I/R)-induced gut barrier dysfunction. Although cytokines are released in I/R, it is unclear whether cytokines directly increase permeability or if this phenomenon requires both expression of cell adhesion molecules and PMN adhesion-activation. Endothelial barrier dysfunction plays an important role in the pathogenesis of multiple organ dysfunction syndrome, inducing gut barrier failure, but the mechanisms are not fully understood. The purpose of this study was to evaluate the potential therapeutic value of inhibition of platelet activating factor (PAF), intercellular adhesion molecule-1 (ICAM-1), and platelet endothelial cell adhesion molecule-1 (PECAM-1) in gut barrier dysfunction induced by intestinal I/R. A PAF antagonist (lexipafant, BB-882) and monoclonal antibodies against rat ICAM-1 (anti-ICAM-1-MAb) and PECAM-1 (anti-PECAM-1-MAb) were used in a model of gut barrier dysfunction caused by intestinal ischemia for 40 min and concomitant reperfusion for 12 h in the rat, and endothelial permeability, myeloperoxidase activity, interleukin-1beta and protease inhibitor levels were evaluated. The endothelial permeability and tissue leukocyte recruitment in the distal small intestine significantly increased in rats with I/R treated with saline. Proteolytic activity in plasma was evident by low levels of the three measured plasma protease inhibitors. These changes were, to different degrees, reduced by treatment with lexipafant, anti-ICAM-1-MAb, or anti-PECAM-1-MAb. Alterations in systemic levels of interleukin-1beta paralleled the changes found in gut barrier permeability and leukocyte trapping. Our results suggest that treatment with the PAF inhibitor lexipafant and monoclonal antibodies against ICAM-1 or, seemingly most efficient, PECAM-1 reduces the severity of I/R-associated intestinal dysfunction, associated with a decrease in systemic concentrations of IL-1beta local leukocyte recruitment, and partly restoring plasma protease inhibitor levels.

Granulocyte lysosomal factors and plasma elastase in uremia: a potential factor of catabolism.

In uremic intoxication proteolytic activity in plasma and striated muscle is enhanced. To get further insights into the underlying mechanisms the lysosomal factors of polymorphonuclear (PMN) leukocytes and the plasma elastase-alpha 1-proteinase inhibitor complex were investigated in patients with acute and chronic renal failure. Lysosomal activity was evaluated in peripheral blood smears by the lysis of erythrocytes and plasma (halo formation) around each neutrophil induced by 0.25 M NaC1 borate buffer. In about half of the patients with chronic renal insufficiency on dietary treatment lysosomal activity of PMN leukocytes was reduced. The plasma concentration of elastase-alpha 1-proteinase inhibitor complex was normal in most subjects, but increased in three patients with the highest serum creatinine levels (greater than 13 mg/d1). In the patients with acute renal failure (ARF) of various origin (postoperatively, septicemia, pancreatitis, or dye-induced) halo formation was either reduced or absent. The plasma elastase-alpha 1-proteinase inhibitor complex was increased in 5/6 of the patients by a factor of two to four. Also in the patients on regular hemodialysis treatment halo formation of PMN leukocytes was substantially reduced, whereas the plasma levels of elastase-alpha 1-proteinase inhibitor complex was slightly increased. The finding of reduced lysosomal activity of PMN neutrophils in uremia may be partly due to an enhanced release of neutral proteinases into the circulation as indicated by the elevated plasma levels of elastase-alpha 1-proteinase inhibitor complex in some patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of severity and prognosis in early stages of septicemia by means of chromogenic peptide substrate assays.

Components of the plasma protease systems were determined by means of chromogenic peptide substrate assays during the early stage of septicemia in 21 patients of whom 11 died. The proenzyme functional inhibition index, calculated from the measured values for plasma prekallikrein, functional kallikrein inhibition, plasminogen and functional antiplasmin and antithrombin III activities, were markedly reduced in both groups, but significantly lower in the fatal cases than in the survivors from the first day of septicemia and throughout the observation period. Fatal septicemia thus appear to be associated with a more extensive proteolytic activity in plasma than nonfatal septicemia and can be readily disclosed by calculation of the proenzyme functional inhibition index.

Deficiency of arginine esterase in cystic fibrosis of the pancreas: demonstration of the proteolytic nature of the activity.

Proteolytic activity, defined as the hydrolysis of peptide bonds involving the carboxyl group of L-arginine, in plasma of patients with cystic fibrosis, heterozygotes, and control subjects has been assayed using a fluorometric method with protamine as the substrate and fluorescamine as the reagent. The mean total proteolytic activity in plasma of patients with cystic fibrosis was approximately one-half the mean total activity in control subjects and heterozygotes. The mean proteolytic activity inhibited by soybean trypsin inhibitor in plasma of patients with cystic fibrosis was approximately one-third that of control subjects and heterozygotes. The relationship of arginine esterase activity to proteolytic activity was investigated. The pH optimum and action of reversible and irreversible inhibitors were similar for both activites, suggesting that the arginine esterase activity and proteolytic activity represent similar catalytic entities. These findings are consistent with our hypothesis that the basic defect in cystic fibrosis may reside in the deficieny of a proteolytic enzyme which results in the accumulation of the various cationic macromolecular "factors" described by other investigators in serum of patients with cystic fibrosis. The demonstration of a deficiency of proteolytic activity as assayed by the hydrolysis of protamine, a cationic polypeptide, could explain the presence of ciliotoxic cationic protein or polypeptide factors in serum of patients with cystic fibrosis and may, in some unknown manner, be related to the clinical manifestations of the disease.

Action &lt;i&gt;in vitro &lt;/i&gt;de l'éthanol sur les activités antitrypsique et protéolytique du plasma et du sérum

In the presence of ethanol, lantitryptic activity of rat plasma, as well as serum, decreased to the same extent through increased dissociation of trypsin inhibitor complexes. Proteolytic activity of rat plasma increased in the presence of ethanol with an effect similar to that of added trypsin. The greater activity of the serum thus became equal to that of the plasma. The proteolytic activity of plasma and part of that of serum could, therefore, be of tryptic nature.

Proteolytic capacity in human plasma. I. Measurement of proteolytic activity in the presence of natural inhibitors and study of the inter-individual variations.

The maximal proteolytic activity in plasma that can be obtained by activation with urokinase and in the presence of natural inhibitors is designated proteolytic capacity. A modified caseinolytic method measuring this parameter has been described. In a normal population large variations between individuals were found, and this is probably due to differences in the plasminogen-plasmin level. The caseinolytic method correlated well with in vitro thrombolysis and with fibrinogenolysis in plasma. Serum had a higher proteolytic capacity than plasma. Pregnancy and the oral contraceptives caused a pronounced rise in proteolytic capacity, whereas thyrotoxicosis caused a decrease in the capacity. Two healthy donors, one with zero proteolytic capacity and a plasminogen level of 35–45%, and one with very high proteolytic capacity and a plasminogen level of about 130% were studied in particular. No increased tendency for thrombosis was found in persons with very low or zero proteolytic capacity.

Plasminogen Activity of Plasma and Serum

Human plasma and serum were obtained from blood of resting persons. Plasminogen was determined by activation with the optimal amount of streptokinase. As in the majority of cases no significant difference was found between the proteolytic activity of plasma and serum, a blood clot cannot contain more plasminogen than that present in the volume of serum included.

Studies on a proteolytic enzyme in human plasma; the relationship between the proteolytic activity of plasma and blood coagulation.

A fraction of globulin was prepared from human plasma which was deficient in prothrombin, thrombin, fibrinogen, plasma thromboplastin, and accelerator globulin. The preparation of globulin contained considerable potential proteolytic activity which could be activated by streptococcal fibrinolysin. This fraction of globulin accelerated the clotting of normal platelet-deficient plasma. However, the clot-accelerating effect of the globulin fraction was the same whether or not its proteolytic property had been activated. The addition of streptococcal fibrinolysin to normal platelet-deficient plasma did not accelerate coagulation. Nor did the addition of streptococcal fibrinolysin to hemophilic platelet-deficient plasma promote its coagulation. The data presented suggest that proteolysis by activated plasma proteolytic enzyme is not an essential stage in the coagulation of the blood.