Protein: creatinine and trypsin inhibitor: creatinine ratios in the urine of marathon runners

We measured changes in the protein: creatinine and trypsin inhibitor: creatinine ratios in the urine of six male marathon runners. Samples of urine were collected before the run, immediately after the run and in 6-h collections for 2 days. We found the greatest increase in the protein: creatinine ratio (2.6 times greater) in urine collected immediately after the run and the greatest increase in the trypsin inhibitor: creatinine ratio in urine samples collected 6-12 and 12-18 h after the run (2 and 3 times greater, respectively). This suggests the existence of different mechanisms for these two physiological processes. The later increase in the trypsin inhibitor: creatinine ratio was perhaps, due to a state of short-lived inflamation and shock after severe physical effort.

Automated measurement of trypsin inhibitor in urine with a centrifugal analyzer: comparison with other acute phase reactants

Automated measurement of trypsin inhibitor in urine was performed with good precision using the COBAS FARA. Elevated levels of both trypsin inhibitor in urine and acute phase proteins in serum were shown in most cases of major abdominal surgery. We suggest that the automated assay of urinary trypsin inhibitor might be useful for the clinical diagnosis of acute phase response.

[Effects of the administration of urinary trypsin inhibitor on the morphology and function of platelets in the rat septic models]

Effects of urinary trypsin inhibitor (UTI) on the number, morphology and function of platelets under septic state were studied in rat models of cecal ligation and puncture (CLP). At formation of CLP, 5,000 U/kg/h of UTI was serially administered intraperitoneally and blood was sampled after 16 hours. Comparative study among sham-operation group, CLP group, and CLP + UTI group revealed: 1) inhibition of the platelets of platelet counts and appearance of large-sized, active platelets by UTI in the CLP + UTI group, 2) increase of platelet maximum aggregation rate (MAR) by ADP and increase of collagen in the CLP group, while inhibition in the CLP + UTI group and 3) by HPLC evaluation of adenine nucleotide in the platelet, increased levels of total ATP and ADP in the CLP group, particularly, increases of ATP in the metabolic pool and ADP in the granular pool. CLP + UTI group did not show these changes in the adenylate pool. UTI was thus considered to stabilize the platelet cycle in sepsis. Platelets under septic state might be hyperactive, and thrombosis is easy to occur. UTI administration might work for maintaining constancy of the platelet internal environment and improve septic state because adenine nucleotide level in the platelet did not change in the CLP + UTI group through changed in the CLP group.

Radioimmunological quantitation of the urinary trypsin inhibitor in normal blood and urine

A radioimmunoassay for measurement of the urinary trypsin inhibitor in human serum and urine is described. Because of the immunological cross-reactivity between the inter-alpha-trypsin inhibitor and the urinary trypsin inhibitor the plasma and serum were treated with perchloric acid to precipitate the inter-alpha-trypsin inhibitor. Gel filtration of serum before and after acid treatment showed identical peaks corresponding to the urinary trypsin inhibitor. The normal level of the urinary trypsin inhibitor in fresh plasma from 30 blood donors was 6.38 +/- 0.33 mg/l (SEM), and in sera from 24 healthy volunteers 7.14 +/- 0.27 mg/l (SEM). In urine from 23 healthy volunteers the normal excretion was 8.17 +/- 1.18 mg/24 h (SEM).

Urinary UK, t-PA and urinary trypsin inhibitor in health and glomerular diseases

The concentrations of two different plasminogen activators(PAs), urokinase (UK), tissue-type plasminogen activator (t-PA) and urinary trypsin inhibitor (UTI) were determined in the urine and blood from 48 normal subjects and 92 patients with glomerulonephritis using highly sensitive enzyme immunoassay (EIA). The values of UK clearance were approximately 1.5-fold larger than those of creatinine clearance and at least 60.8% of UK was reabsorbed in the renal tubules, which suggest that one of major secretion site of UK is located in the outer region of the glomerular basement membrane (GBM), that is glomerular epithelium. Decreased urinary excretion of UK was observed in the glomerular disease depending on their severity and correlated with the increasing degree of FDP D-dimer excretion. On the other hand, the values of t-PA clearance were quite smaller than those of creatinine clearance, which suggest that urinary t-PA originated from the blood circulation or the inner side of the GBM (possibly glomerular endothelium) and filtrated from the GBM. Like UK, urinary t-PA also decreased in glomerular diseases. UTI which is highly anionic and has a comparable size with albumin was excreted increasingly in glomerulo-nephritis due to loss of the anionic charge barrier of the GBM. No significant correlations were noted between UTI excretion and UK or t-PA excretion.

Inter-alpha-trypsin inhibitor. Inhibition spectrum of native and derived forms

The conversion of inter-alpha-trypsin inhibitor (I alpha I) into active, acid-stable derivatives by proteolytic degradation has been tested with 10 different proteinases. Of these, only plasma kallikrein, cathepsin G, neutrophil elastase, and the Staphylococcus aureus V-8 proteinase were found to be effective, each releasing more than 50% of this activity. However, a strong correlation between inhibitor degradation and significant release of acid-stable activity could only be found with the V-8 enzyme. Inhibition kinetics for the interaction of native I alpha I, the inhibitory fragment released by digestion with S. aureus V-8 proteinase, or the related urinary trypsin inhibitor, with seven different proteinases indicated that all had essentially identical Ki values with an individual enzyme and, where measurements were possible, nearly identical second order association rate constants. Significantly, none of the five human proteinases tested, including trypsin, chymotrypsin, plasmin, neutrophil elastase, and cathepsin G, would appear to have low enough Ki values to be physiologically relevant. Thus, the role of native I alpha I or its degradation products in controlling a specific proteolytic activity is still unknown.

[Effective method of simultaneous extraction from the urine and purification of tissue kallikrein and acid-stable trypsin inhibitor]

A simple preparative procedure is developed for simultaneous isolation from urine of tissue kallikrein and acid stable trypsin inhibitor. The procedure involved adsorption of these proteins on chitosan at pH 5-6 and the subsequent elution with 1 N NH4OH, which enabled to obtain the enzyme and inhibitor with a yield of 80-90% and to purify 10-fold each of these components. Use of chitosan facilitated and simplified distinctly the large scale isolation from urine of the kallikrein and trypsin inhibitor, required for medicinal and diagnostic purposes.

A proteoglycan related to the urinary trypsin inhibitor (UTI) links the two heavy chains of inter-alpha-trypsin inhibitor

cDNA studies have suggested that inter-alpha-trypsin inhibitor (ITI) is a complex of several different peptide chains; the sequence of the inhibitory part of ITI is in excellent agreement with that of the urinary trypsin inhibitor (UTI). The present report demonstrates that a compound immunologically related to UTI is released by digestion with porcine pancreatic elastase or human leucocyte elastase. Since UTI has been shown to be a proteoglycan, ITI has been treated by chondroitinase. In these conditions, ITI is dissociated and gives rise to two heavy chains (78 and 85 kDa) and one light chain (26 kDa) immunologically related to UTI and which in PAGE moves close to UTIc (produced by chondroitinase treatment of UTI). We suggest that ITI is a non-covalent complex comprising two heavy chains and one light chain immunologically related to UTI and which is also a proteoglycan.

Clearance and distribution of acid-stable trypsin inhibitor (ASTI)

The clearance, organ distribution and metabolic pathway of the acid-stable trypsin inhibitor (ASTI) were studied in mice using 125I-labeled urinary trypsin inhibitor (UTI), the most typical ASTI in the urine. Following intravenous injection of 125I-UTI, the radioactivity disappeared rapidly from the circulation with a half-life of 4 min for the initial part of the curve. Gel filtration of plasma samples revealed that the rapid disappearance of the radioactivity was due to elimination of free inhibitor from the plasma. 125I-UTI was cleared primarily in the kidney. Gel filtration of urine samples showed that part of the radioactivity in the urine appeared at the same elution volume as 125I-UTI in the plasma, indicating that the origin of UTI was ASTI in the plasma.

Measurement of urinary trypsin inhibitor in urine, plasma and cancer tissues of patients with stomach cancer

Antiserum was obtained from rabbits immunized with a highly purified preparation of urinary trypsin inhibitor (UTI) conjugated with rabbit serum albumin. Anti-UTI antibody did not cross-react with antibody against inter-alpha-trypsin inhibitor (I alpha I) as determined by immunodiffusion against human plasma. A highly sensitive enzyme immunoassay was developed for the determination of UTI-related antigens (UTIR) in plasma, urine and cancer tissues. The level of UTIR correlated with UTI activity in urine. UTIR levels in urine and plasma did not change with age, but UTIR levels were higher in the stomach cancer tissue than in the surrounding stomach mucosa. UTIR levels did not correlate with I alpha I levels in the plasma of patients with stomach cancer, thus the increase was not considered due to the contamination of circulating I alpha I in the cancer tissues.

Improvement of the sensitivity of mono- and bi-dimensional immunoelectrophoretic techniques by transfer onto nitrocellulose

The sensitivity of crossed immunoelectrophoresis (CIE) and rocket immunoelectrophoresis (RIE) does not usually permit the study of diluted protein solutions or the detection of trace components. Antigen-antibody precipitates obtained after immunoelectrophoresis were therefore dissociated and transferred from the agarose gel onto nitrocellulose filter by electrophoresis at pH 11. Immunochemical detection of proteins was then performed with the peroxidase-anti-peroxidase method. Diluted (1/100) solutions gave patterns similar to those obtained with the starting biological fluid. As an example, this technique was applied to human inter-alpha-trypsin inhibitor present at concentrations in the nanogram range. Other proteins, differing in charge and/or molecular weight, were also identified.

Enhanced urinary trypsin inhibitory activity in gentamicin-induced nephrotoxicity in rats

We delineated in rats, the relationship between trypsin inhibitory activity in the urine and the nephrotoxic effects of gentamicin, eg, proteinuria and deterioration of glomerular filtration rate (GFR), measured by creatinine clearance. Gentamicin, 70 mg/kg per day, was injected intraperitoneally for 6-10 successive days. Serum and urine gentamicin levels were determined by a microbiological test. Trypsin inhibitory activity was assayed by the casein digestion method. The results showed a steady increase in urinary trypsin inhibitory activity starting from the fourth injection day. The increased levels of urinary trypsin inhibitory activity were associated with increased levels of urinary gentamicin excretion (r = 0.36, p less than 0.02, n = 50 after the fourth injection day), and were significantly higher than in control groups (p less than 0.001). The urinary trypsin inhibitory activity was inversely correlated with the GFR (r = -0.45, p less than 0.01, after the second injection day). The serum trypsin inhibitory activity remained unchanged throughout the study period in all groups. These data suggest that increased urinary trypsin inhibitory activity may be involved in the pathogenesis of gentamicin-induced nephrotoxicity.

Expression and excretion of human pancreatic secretory trypsin inhibitor in lipoprotein-deletion mutant of Escherichia coli

We constructed a gene coding for the 56-amino acid human pancreatic secretory trypsin inhibitor (PSTI), and ligated it on a plasmid downstream from the trp promoter and the signal peptide sequence of alkaline phosphatase. The resulting plasmid was transfected into a lipoprotein deletion mutant (Escherichia coli JE5505) and the plasmid-carrying cells were induced with 3-indoleacrylic acid. A considerable amount (50 micrograms/ml culture) of the mature PSTI protein was detected in the culture supernatant. The excreted PSTI was identical to the natural PSTI protein with respect to the trypsin-inhibiting activity, the N-terminal and the C-terminal amino acid sequences and the amino acid composition.

[Trypsin inhibitor in the urine of patients with glomerulonephritis]

Concentrations of urinary trypsin inhibitor (UTI) and acid stable antitryptic activity (AS-ATA) were estimated in morning urine of 50 patients with chronic glomerulonephritis and of 13 healthy persons in order to detect interrelationship between severity of kidney impairment and the content of the inhibitor in urine. In healthy persons concentrations of UTI and AS-ATA were equal to 1.05 +/- 0.15 micrograms/ml and 0.12 +/- 0.04 IU/ml, respectively. Similar values of the substances were detected in patients with latent form of glomerulonephritis and normal kidney function. Statistically distinct (P less than 0.01) increase of both these inhibitors was found in urine of patients with latent form of glomerulonephritis and impaired kidney function (4.77 +/- 1.24 micrograms/ml and 0.39 +/- 0.15 IU/ml, respectively) as well as with nephrotic form (26.17 +/- 7.55 micrograms/ml and 1.37 +/- 0.35 IU/ml, respectively) of glomerulonephritis of both primary type and caused by accompanying systemic diseases. Further increase in concentration of UTI up to 31.74 +/- 7.38 micrograms/ml and activation of AS-ATA in urine was observed in the patients with nephrotic form of glomerulonephritis at the step of chronic kidney insufficiency. The increase in UTI concentration observed did not correlate with the level of leukocyturia. Proteinases of monocytes, mast cells, fibroblasts, involved in inflammation and formation of connective tissue in kidney, but not of enzymes from polymorphonuclear leukocytes, appear to be responsible for formation of UTI out of its precursor inter-alpha-trypsin inhibitor in glomerulonephritis.

Human inter-alpha-trypsin inhibitor and immunologically related inhibitors investigated by quantitative immunoelectrophoresis. II. Pathological conditions

Inter-alpha-trypsin inhibitor (I alpha I) and the immunologically related prealbumin-like-migrating proteinase inhibitor (pA-PI) were investigated by crossed immunoelectrophoresis in sera from 68 persons with myocardial infarction, neoplastic diseases, inflammatory diseases, collagenosis, cirrhosis of the liver or uremia. The concentration of pA-PI in serum increased during each of these diseases (p less than 0.01). The concentration of I alpha I was significantly decreased in patients with cirrhosis (p less than 0.01). In day to day studies of a patient with myocardial infarction, a patient with erysipelas and a postoperative patient the concentration of I alpha I was low normal to decreased in the first days of the conditions and increased thereafter to high normal values. A comparison of the concentration of pA-PI with the excretion of the immunologically identical urinary proteinase inhibitor (UPI) showed that the excretion could not be caused by simple overflow of pA-PI in the kidney. The excretion of UPI followed closely the acute-phase-response, as measured by serum C-reactive protein.

The effect of the glycosaminoglycan chain removal on some properties of the human urinary trypsin inhibitor

The major urinary trypsin inhibitor UTI I is a proteoglycan. UTI c (Mr 26,000), produced by chrondroitin lyase digestion of UTI I, was isolated and characterized. About 90% of the glycosaminoglycan chain was removed by this treatment without proteolytic modification, as assessed by amino-acid composition and N-terminal sequence of UTI c. Its electrophoretic mobilities on alkaline and SDS-PAGE are identical with those of UTI II which occurs in urine during storage. To study the role of the glycosaminoglycan chain on the inhibitory properties of UTI I, UTI I and UTI c were compared using different proteinases as target enzymes. The inhibitory activity towards bovine trypsin and chymotrypsin as well as human granulocytic cathepsin G did not differ significantly. However, towards human granulocytic elastase, the equilibrium dissociation constant (Ki) is 5 times higher for UTI c than for UTI I. Weak inhibitory activities were measured on human plasmin, UTI c being more efficient than UTI I. The acid-stability of UTI I is not modified after chrondroitin lyase treatment. UTI I and UTI c are equally sensitive to trypsinolysis indicating that the covalently bound glycosaminoglycan chain does not play an important role for the stability of UTI I.

Human inter-alpha trypsin inhibitor and immunologically related inhibitors investigated by quantitative immunoelectrophoresis. I. Method and reference material

The concentration in serum of inter-alpha trypsin inhibitor (I alpha I) and its immunologically related inhibitor, the prealbumin-like proteinase inhibitor (pA-PI), was investigated by quantitative crossed immunoelectrophoresis (CIE) in 33 healthy persons. The corresponding urinary excretion over a 4 h period of the immunologically related urinary proteinase inhibitor (UPI) was measured by rocket immunoelectrophoresis. The concentration of pA-PI increased significantly (p less than 0.001) with age whereas that of I alpha I and the urinary excretion of UPI were independent of age. There was no significantly difference in the concentration of the inhibitors in serum between the sexes, but females were found to have a lower urinary excretion of UPI than males (p less than 0.05). Furthermore we found no significant variation in the concentration of the inhibitors during the course of the day or from day to day over a 5 day period. Results obtained by rocket immunoelectrophoresis correlated well with enzymatically measured trypsin inhibitory activity.

The major human urinary trypsin inhibitor is a proteoglycan

The major urinary trypsin inhibitor (Mr 44 000), isolated from human urine, contains 35% carbohydrate. In addition to N-acetylglucosamine and neutral sugars (primarily mannose and galactose), the carbohydrate moiety contains hexuronic acid and N-acetylgalactosamine and corresponds to a glycosaminoglycan. This carbohydrate chain is an integral component of the inhibitor: it does not dissociate from the inhibitor when using dissociative conditions such as sodium dodecyl sulfate, guanidinium chloride, or by increasing ionic strength or mixing with cetylpyridinium chloride. This glycosaminoglycan chain is sensitive to chondroitinase ABC or testicular hyaluronidase digestion and corresponds to slightly sulfated chondroitin 4-sulfate or 6-sulfate. After treatment by these enzymes, the urinary inhibitor has a lower molecular mass (Mr 26 000) but still inhibits trypsin.

Immunochemical determination of the serum protein reacting with antibody against human urinary trypsin inhibitor by single radial immunodiffusion: use of polyethylene glycol

A single radial immunodiffusion method is described for determining the serum protein which reacts with antibody against the urinary trypsin inhibitor, but does not react with anti-inter-alpha-trypsin inhibitor antibody. Since the amount of this protein could not be determined with an agar plate containing antibody alone, we first prepared an agar plate containing 4% polyethylene glycol 6 000 and 1 mg of anti-urinary trypsin inhibitor gamma-globulin and confirmed that the amount of this protein could be measured accurately from the sizes of precipitin rings after 72 h incubation at room temperature. Levels of this serum protein, alpha 1-antitrypsin, alpha 2-macroglobulin and inter-alpha-trypsin inhibitor were measured in normal human serum by the single radial immunodiffusion method, and it was confirmed that the level of this serum protein did not correlate with the levels of these 3 other proteins.

Characterization of a human interleukin 1 inhibitor

Human urine contains a specific inhibitor of interleukin 1 (IL 1) that is found in increased amounts during fever. This inhibitor was purified by using a sequence of ammonium sulfate fractionation, DEAE cellulose ion-exchange chromatography, molecular sieve chromatography on Sephacryl S-200, affinity chromatography on concanavalin A (Con A) Sepharose, and polyacrylamide gel electrophoresis. Two peaks of IL 1 inhibitory material were eluted from the polyacrylamide gels. One peak contained three proteins of 29, 32, and 67 kd, respectively, which could be visualized by silver staining. The second peak contained only a small amount of the 67 kd protein. A partially purified inhibitor fraction was found to cross-react with antisera directed against two low m.w. urine trypsin inhibitors that are cleavage products of the serum inter-alpha-trypsin inhibitor. Although these findings suggest that the urine IL 1 inhibitor may be related to the inter-alpha-trypsin inhibitor, a more exact identification will require either a homogeneous inhibitor preparation or a monospecific antiserum.

Purification and some properties of a low molecular weight trypsin inhibitor from acute pancreatitis urine

Urinary trypsin inhibitors (UTIs) from the urine of a patient with acute pancreatitis consisted of three forms with different molecular weights. These were highly purified by ammonium sulfate precipitation, Sephadex G-75, SP-Sephadex C-25 and trypsin-Sepharose 4B column chromatography. The lowest molecular weight of UTIs was estimated to be 6,200 daltons. Moreover, five residues of N-terminal amino acids and a C-terminal amino acid were the same as those of pancreatic secretory trypsin inhibitor.

Isolation of acid-resistant urinary trypsin inhibitors by high performance liquid chromatography and their characterization by N-terminal amino-acid sequence determination

Two crude fractions of acid-resistant trypsin inhibitors (apparent molecular masses 44 and 20 kDa, respectively) were prepared from human urine by gel permeation chromatography. From both preparations the pure inhibitors were isolated by high performance liquid chromatography (HPLC). Their N-terminal amino-acid sequences were determined and compared with those of HI-30 and HI-14 as isolated by reversible binding to either immobilized trypsin or immobilized chymotrypsin. The N-terminal amino-acid sequence of the high-molecular mass inhibitor UI-I isolated by HPLC was identical with those of HI-30 and UI-C-I isolated via immobilized trypsin or chymotrypsin, respectively. The low-molecular mass inhibitors UI-II and UI-C-II differ from HI-14 by the N-terminal extension Glu-Val-Thr-Lys-when obtained by HPLC or by the extension Thr-Lys-when obtained via immobilized chymotrypsin, respectively. The comparison of these N-termini with the amino-acid sequence of HI-30 (Ala1-...-Val16-Thr-Glu-Val-Thr-Lys-HI-14) defines the low molecular urinary trypsin inhibitors as proteolytic degradation products of the high-molecular urinary inhibitor. Proteolysis may occur at different bonds. The existing discrepancies in molecular architecture and in molecular masses of the urinary trypsin inhibitors are discussed.

[Concentration of acid-stable inhibitors--metabolites of plasma inter-alpha trypsin inhibitor--in the urine of healthy people and in patients with nephrotic syndrome]

Concentration of acid stable inhibitors (ASI)--metabolites of plasma inter-alpha-trypsin inhibitor--was measured in urine samples of healthy persons and of 6 patients with nephrotic syndrome by means of modified cross immunoelectrophoresis. There was obtained 2-25 mg of ASI (Mr 22,000 and 32,000) in diurnal urine samples of patients with nephrotic syndrome, which were 10-20 times higher as compared with these inhibitors level in the urine of healthy persons. The reverse correlation was established for the value of glomerular filtration and the lever of ASI (Mr 32,000) in the urine of patients with nephrotic syndrome.