Search

Determination of serum enzymatic activities in hepatosplenic bilharziasis (H.S.B.) were conducted in 100 bilharzial patients, in different stages and 30 controls SGot, SGPT, ALK pH, ALD and SLDH with its both fractions heat stable and labile.). Early elevation of serum enzymatic activities of SGOT, SGPT and SALK. pH, may be considered as a sensitive parameter for functional changes in H.S.B. rather than other conventional liver function tests. The elevated enzymic activity of total LDH in this study was associated with elevation in its both fractions. In particular, the changes in the total activity was in parallel with that of its heat labile fraction. The latter may be considered as a confirmatory test for marked deterioration of liver functions in H.S.B. The changes in the heat stable fraction was inconstant and may be attributed to extrahepatic bilharzial dissimilation. Significantly high serum enzymatic activity of SALD was found in cases of H.S.B. particularly those showing striking muscle wasting.

The time course of effects of S. mansoni infection on hepatic microsomal drug metabolizing enzymes was studied in swiss albino mice. Aminopyrine demethylase and aniline hydroxylase showed increases in activity, reaching a peak 30 days post infection. Both enzymes demonstrated a steady decline thereafter. On day 60, the level of aminopyrine demethylase was comparable to that of uninfected mice. On the other hand, the activity of aniline hydroxylase was lower than the control values. Treatment with lindane (40 mg/Kg/day X 3) increased the activity of both enzymes after different durations of disease induction. Changes in hepatic microsomal enzymes in S. mansoni infection may alter the intensity and duration of pharmacologic or toxic effects of drugs eliminated from the body through metabolic transformation.

Plasma and erythrocyte lipid abnormalities occur in chronic human schistosomiasis mansoni and appear to be related to mild lecithin:cholesterol acyltransferase (LCAT) deficiency. Plasma LCAT activity is about 50% lower than normal in decompensated hepatosplenic schistosomiasis, whilst the plasma concentrations of cholesteryl ester and lysolecithin and decreased and that of lecithin increased in the earlier hepatointestinal and compensated hepatosplenic forms of the disease as well as in the later decompensated stage. Plasma lipoproteins are also altered in schistosomiasis. Agarose gel electrophoresis showed reduced alpha and pre-beta lipoproteins, whilst other studies consistently showed that lipoproteins from patient plasma are better substrates for LCAT than those of normal plasma. Erythrocyte cholesterol is increased in all forms of the disease, and the cells show increased resistance to lysis either in hypotonic media or in 0.3 M glycerol. The severity of these lipid changes clearly shows a gradation through the successive stages of the disease. In the experimentally infected mouse LCAT deficiency does not seem to be a feature of the disease, but several significant changes in plasma and erythrocyte lipids occur which contrast with those seen in human schistosomiasis.

We have postulated that an insufficient active of collagenase relative to increased collagen synthesis may be the cause of the increased collagen accumulation in fibrotic tissues. In the present study, 125I-collagenase and rabbit anti-collagenase immunoglobulin G were used to develop a sensitive radioimmunoassay that detects 0.1 nM (3 ng) of collagenase protein in tissue samples. The assay also can detect collagenase protein that is associated with extracellular-matrix collagen fibrils. Good correlation with an assay of enzyme activity validates the radioimmunoassay for quantification of collagenase. The assay was used to measure amounts of collagenase in relation to fibrotic processes in livers of mice with schistosomiasis. Results indicate that the amounts of collagenase relative to synthesized collagens were significantly lower, and this may contribute to the progressive fibrosis. The occurrence of a maximum amount of collagenase at 7 weeks after infection with Schistosoma mansoni cercariae in concanavalin A-treated animals, as compared with 8 weeks in controls, could account for the large remission of fibrosis in mice so treated. The results emphasize the possible importance of collagenase in controlling or limiting fibrosis.

The effect of unisexual schistosome infection on the activities of several hepatic enzymes was studied in mice. The activities of hepatic drug-metabolizing enzymes in mice infected with either female or male schistosomes were not significantly different from those of noninfected control animals. However, the total amount of heme pigment in the liver of infected mice was 2.7 (female infection) and 8.9 (male infection) times greater than that of control animals. The durations of hexobarbital sleeping times and of zoxazolamine paralysis in unisexual schistosome infections did not differ from those of uninfected controls. Therefore, an accumulation of schistosome pigment without egg deposition, as in this unisexual infection study, does not result in a severe reduction of hepatic drug-metabolizing capacity.

Oral oxamniquine 800 mg/m2 body surface area/day in divided doses for 2 days, was given to 57 children with schistosomal infections. Haematological and biochemical tests suggest that this drug is safe, even in the presence of significant liver enlargement. Parasitological investigations in 32 children who were followed up for 1 month indicate that oxamniquine is effective in the treatment of S. mansoni infection, but that it has little effect on S. haematobium infection.

The urinary activities of alpha-naphthyl acetate esterases were measured for groups of bilharzial and nonbilharzial patients with benign urologic diseases and for others with bladder cancer. All these patients showed elevation in the urinary enzyme activity over that given by healthy controls. Bilharzial and nonbilharzial bladder cancer patients exhibited significant increase in urinary enzyme activity as compared with corresponding groups with benign urologic diseases A level of 50 units of enzyme activity was taken as a limit to discriminate between bladder cancer patients and those patients with benign urologic diseases. The specificity and sensitivity of this urinary test exceeded 90% with low falsely positive and negative results. The data of the present study recommended the use of urinary alpha-naphthyl acetate esterases activity as a preliminary screening test for bilharzial and nonbilharzial bladder cancer patients.

Sera from mice infected with Schistosoma mansoni were found to contain substantial amounts of an acid-active hemoglobinolytic enzyme. Recovery of this enzyme from aliquots of pooled 12-week infected serum, using a phenylalanine-agarose affinity column, showed that a portion of the enzyme binds tightly to the column at pH 4.0, and can be eluted with 0.01 M formic acid. Another larger portion of hemoglobin-digesting activity is not bound to the column and emerges with the buffer front. Sera from rats which were exposed to cercariae, but in whom worms were stunted and did not develop to maturity, were found not to contain hemoglobin-active protease. At the present time, the source of the enzyme has not been unequivocably proven. The enzyme found in the serum binds to and releases from the affinity column in the same manner as does hemoglobinase recovered from freeze-dried S. mansoni worms. Maximal activity of both enzymes against the substrate occurs at pH 4.5-5.0. Present evidence suggests that the protease present in the serum is of worm origin. It is postulated that this protein may be excreted by the parasite during the process of regurgitation of gut contents. Presence of worm enzyme circulating in the host plasma would correlate with the known sensitization of the host to schistosomal hemoglobin-digesting enzyme.

Serum angiotensin-converting enzyme (SACE) activity was significantly higher in 90 patients with sarcoidosis (55 +/- [S.D.] 23 nmol min-1 ml-1) than in 80 healthy controls (34 +/- 9 nmol min-1 ml-1). Steroid therapy modified SACE activity; 60 sarcoidosis patients who were not being treated with steroids had significantly higher enzyme activities (58 +/- 24 nmol min-1 ml-1) than 30 steroid-treated sarcoidosis patients (40 +/- 19 nmol min-1 ml-1). In 50% of the non-steroid treated sarcoidosis patients SACE activity was more than 2 S.D. above the mean value for the controls. SACE activity was measured in 22 tuberculous patients (38 +/- 14 nmol min-1 ml-1), 20 leprosy patients (34 +/- 9 nmol min-1 ml-1), 31 with primary biliary cirrhosis (44 +/- 20 nmol min-1 ml-1), 26 with inflammatory bowel disease (31 +/- 9 nmol min-1 ml-1), 8 with hepatic granulomatous disease, 5 with Hodgkin's disease, and 2 with schistosomiasis. The combined false-positive rate for these non-sarcoidosis patients was 10%. Serial SACE assays provide useful information on the course of sarcoidosis and response to steroid treatment.

It has been previously demonstrated that collagenase activity and collagen synthesis in hepatic granulomas of mice infected with S. mansoni cercariae are maximal 8 weeks after infection; however, total liver collagen content continues to increase. Now the anatomic relationships among collagenase and collagen, granulomas, and hepatic parenchyma in normal mice and in mice infected with S. mansoni are studied. Trypsin-activated collagenase was purified from the media of cultured granuloma explants and anti-collagenase immunoglobulin G was purified from immunized rabbits. The IgG cross-reacted with liver granulomas and active and inactive forms of collagenase, but did not react by immunodiffusion in agar with other neutral proteases or homogenates of schistosome eggs or normal liver. Cryostat sections of liver from normal and infected mice were studied by indirect immunohistochemical methods using fluorescein, rhodamine, and peroxidase labels. Collagenase localization was restricted to areas of collagen deposits in granulomas and hepatic parenchyma. Ultrastructural studies revealed collagenase on the surface of collagen fibers. Hepatocytes of normal mice showed delicate staining at the sinusoidal surface. At all times, immunoreactive collagenase was intimately associated with its substrate, where it presumably initiated collagen degradation. This localization provides a rationale for possible therapeutic approaches to control fibrogenesis through collagenase induction or activation.

Angiotensin-1-converting enzyme (A1CE) activity was assessed in macrophages isolated from hepatic egg granulomas at 7 and 20 weeks after the infection of mice with Schistosoma mansoni. At 2 h after isolation, granuloma macrophages (GM) from chronically infected mice (20 weeks) displayed significantly higher levels of A1CE than did GM from mice 7 weeks after infection; both of the values were significantly higher than control peritoneal resident macrophages from normal mice. A1CE activity in GM and their respective culture supernatants declined over a 72-h period of in vitro cultivation; however, the decline was abrogated with the addition of dexamethasone to the culture medium. GM from athymic mice displayed significantly higher A1CE activity than did those from normal controls. Our data confirm and extend previous findings of others that GM are a major source of A1CE in murine schistosomiasis and that lymphocyte function may regulate GM A1CE production.

Mice were infected with 1000 Schistosoma haematobium cercariae (Egyptian strain). Histopathological and histochemical studies were performed on the different organs, during the first four weeks after infection and on the fourth week after oviposition. Pathological changes during early prepatency matched with those in S. mansoni infection. Eggs were laid in aggregates in the colon and liver. They initiated the development of typical granulomatous lesions. Abundant bilharzial pigment and areas of sclerosis were present in both liver and spleen. The heart, kidneys and urinary bladder were pathologically free. Disturbed succinic dehydrogenase and acid phosphatase enzyme levels were detected which point to a derangement in the functions of the cell organelles.

The study included 916 schistosomal patients and 97 controls. The prevalence of HBs-Ag and anti-HBs was significantly higher in the bilharzial patients compared to controls. Their frequency was higher in the ascitic than the hepatosplenic group, and the difference between each and the simple group was highly significant. Cases with current jaundice showed highly significant frequency of both HBs-Ag and anti-HBs compared to those with no history or manifest jaundice at the time of study. In addition, cases with raised bilirubin, SGPT and SGOT showed significantly higher frequency of HBs-Ag and anti-HBs compared to cases having normal levels. On the other hand, the frequency was not affected by the level of serum alkaline phosphatases. As regards liver pathology, cases with mixed pathologic picture showed significantly higher frequency of both HBs-Ag an anti-HBs compared with those having pure schistosomal lesions.

The activity of procollagen prolyl hydroxylase was measured in fibrotic liver obtained from mice with hepatosplenic schistosomiasis, an animal model of the most prevalent form of human liver fibrosis. Measurable activity of prolyl hydroxylase in fibrotic liver supernatants was 47-fold higher than that of normal liver. The effect of prolyl hydroxylase inhibition on collagen synthesis in fibrotic liver slices was studied, using 8,9-dihydroxy-7-methyl benzo[b]quinolizinium bromide (GPA 1734). This compound was shown in other systems to inhibit prolyl and lysyl hydroxylations by iron chelation at concentrations which did not affect total protein synthesis. The formation of nondialyzable labelled hydroxyproline was inhibited by GPA 1734, 40, 70 and 95% at 30, 50 and 100 micrometer, respectively. Incorporation of proline into total liver protein was unaffected at 30 and 50 micrometer, but was inhibited 20% at 100 micrometer GPA 1734. Underhydroxylated collagen synthesized by liver slices with GPA 1734 was extracted with neutral salt solution and was subsequently hydroxylated with partially-purified prolyl hydroxylase to the same extent as control material synthesized in the absence of GPA 1734.

The serum activities of monoamine oxidase (MAO), gamma-glutamyl transferase (GGT) and glutamic dehydrogenase (GDH) enzymes were measured in 25 patients with Schistosoma mansoni infection (Group I), 26 patients with schistosomal hepatosplenomegaly and ascites (Group II) and 21 normal controls. The activities of these enzymes were compared with those of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP). The mean levels of MAO, GGT and GDH of Group I were not significantly different from controls. The mean levels of MAO and GGT in Group II, however, were significantly different from corresponding mean levels of Group I and the controls at P less than .001. Changes in the mean level of GDH and ALT were not significant. By contrast, the levels of AST and ALP in both groups showed significant elevation over control levels at P less than .001. These results indicate that estimation of the two enzymes MAO and GGT may aid in the biochemical differentiation of the stages of schistosomiasis and their associated hepatic complications.

The effect of active schistosomiasis on the activity of some serum enzymes of hepatic origin has been studied in 46 male Egyptian patients with S. mansoni infections. These enzymes included total lactic dehydrogenase and its isoenzymes, 5'nucleotidase, B-glucuronidase, ornithine carbamyl transferase and sorbitol dehydrogenase. Samples were collected on admission, a week after the end of treatment and one month later. B-glucuronidase showed no change whereas ornithine carbamyl transferase, sorbitol dehydrogenase and 5'-nucleotidase showed elevated levels throughout the study. Total LDH was not significantly different on admission but increased significantly after treatment and returned to normal at follow up. Of the five LDH isoenzymes only LDH4 showed elevated levels. The significance of these findings in relation to conventional liver function tests is discussed.

The effects of infection with Schistosoma mansoni on the activities of several hepatic drug-metabolizing enzymes were investigated in congenitally athymic homozygotic nude mice and in a heterozygotic strain of BALB/c derived mice. In athymic nude mice, infection with schistosomes of the same duration and intensity (in terms of the number of eggs in the liver) as in heterozygotic mice resulted in a much smaller reduction in hepatic drug-metabolizing enzyme activities. Therefore, the severe reductions of the hepatic drug-metabolizing function in this infection occur only in mice that are immunologically competent and, thus, are dependent on the host's response to the parasite eggs.

Thirty-two female mice infected with Schistosoma mansoni and 16 non-infected control mice were studied. They were killed by cervical dislocation, dissected and their ovaries examined histopathologically and histochemically. Ovaries of infected mice showed definite structural damage. No ova, worms or specific granulomata were detected. The study points to a possible immunological mechanism producing such changes simulating those occurring in schistosomal nephropathy. Detection of immune complexes in such organs is recommended.

The prevalence of schistosomiasis in Egypt, its suspected relationship to carcinoma of the bladder, and the inevitable exposure of schistosomal patients to insecticides prompted the undertaking of this study. Dimethylnitrosamine (DMN) demethylases, responsible for the activation of DMN, were assessed in the hepatic microsomes from albino mice under the influence of Schistosoma mansoni infection and/or lindane administration. DMN-demethylase I responded to infection by an early increase in activity, reaching a peak 30 days after disease induction and declining sharply afterwards. DMN-demethylase II followed the same general pattern, but it reached its peak 20 days after infection and declined at a slower rate than DMN-demethylase I. The effects of lindane, an organochlorine insecticide, were also studied on these two enzymes in uninfected mice and in S. mansoni-infected animals after different durations of disease induction. Given orally, in a dose of 40 mg/kg/day for 3 consecutive days, lindane increased the activity of both enzymes. Since DMN requires metabolic activation for its hepatotoxic and carcinogenic actions, alterations in its activating enzymes, as a consequence to schistosomiasis and/or exposure to lindane, may change susceptibility to its toxic and carcinogenic potentials.

Cholylglycine levels were measured by radioimmunoassay in sera from 10 control CFI female mice and 22 CFI female mice experimentally infected with Schistosoma mansoni. Cholylglycine was significantly elevated in sera of all but one of the chronically infected animals. Serum aspartate transaminase was within normal limits in all the infected animals; while five infected mice had elevated serum alkaline phosphatase and all these five also had high levels of serum cholylglycine. Marked hepatic histopathological changes were demonstrated in all the infected animals. The data suggest that serum cholylglycine is a highly sensitive index for hepatic dysfunction in chronic hepatic schistosomiasis mansoni.

Fecal pellets of mice infected with Trichinella spiralis, Hymenolepis nana, and Schistosoma mansoni have been found to contain high levels of phospholipase B activity. The rise, time course and decline of the enzymatic content of the pellets correlate with the known patterns of intestinal injury and reaction due to the parasites or their eggs. Treatment with drugs (thiabendazole, niclosamide, niridazole) which are effective in suppressing the infection also prevents the rise, or causes an early decline, in the titers of phospholipase B appearing in the excreta. These findings complement the previous reports of a close correlation between accumulation of this enzyme in the intestine and infection of mice with T. spiralis and H. nana. Determination of fecal phospholipase B activity constitutes a relatively simple, quantitative, and blood-free method of following the course of infection and its response to treatment, which might be of particular advantage in long term studies and preliminary therapeutic screening.

Leucine aminopeptidase (LAP) activity and creatinine concentration was estimated in serum of twenty five normal adult subjects, twenty four cases with active urinary bilharziasis, eleven cases with active intestinal bilharziasis, ten cases with mixed bilharzial infection (urinary and intestinal), fourteen bilharzial cases with clinical hepato-splenomegaly of bilharzial etiology, thirteen bilharzial cases with clinical hepatosplenomegaly and ascites, and twelve cases with cancer bladder of bilharzial etiology. Significant elevation in the serum enzyme level was found in all bilharzial cases which generally ran parallel to the course of the disease, being more marked in hepatosplenomegalic cases than in cases which showed no clinical signs of liver or spleen involvement. However, it was observed that the enzyme level was lower ascitic than in nonascitic cases. For serum creatinine concentration, no significant variation from normal value was observed in the group of patients with active urinary, active intestinal, mixed infections of bilharziasis and bilharzial hepatosplenomegalic cases. However, a very highly significant decrease in serum creatinine concentration was observed in the group of patients with bilharzial hepatosplenomegaly and ascites. Serum LAP activity and creatinine concentration in the group of patients with cancer bladder of bilharzial etiology showed no statistical variation from normal values.

Schistosomulum-released products (SRP) have been shown to enhance both expression of rat and human eosinophil Fc receptors and IgG-dependent cytotoxicity. The present work provides additional evidence of the secretion of eosinophil-enhancing factors by schistosomula and other developmental stages of schistosomes, including adult worms. The heat lability, as well as the strong inhibition of the stimulating activity of SRP by the protease inhibitor Trasylol, suggest that thermolabile proteases secreted by the parasite are involved in this mechanism. The purification of the schistosome proteases by preparative isoelectric focusing and gel filtration demonstrated that neutral proteases able to hydrolyze the collagenase substrates Azocoll and Z-Gly-Pro-Leu-Gly-Pro are able to significantly enhance eosinophil effector functions. Purified Clostridium histolyticum collagenase was also able to mimic the enhancing effect of schistosome proteases, suggesting involvement of a collagenase-like activity of the enzymes in the eosinophil stimulation.

Mice infected with Schistosoma mansoni represent a model for study of the most prevalent form of hepatic fibrosis in humans. In the present study, collagenase activity was measured in relation to collagen synthesis and accumulation in the livers of mice 6-11 wk after after infection. Total and latent collagenase and elastase activities and collagen synthesis were maximal 8 wk after infection and decreased thereafter, whereas collagen content progressively increased to the 11th wk. Maximal enzymatic activity coincided with the known peak of host cellular immune responses. Collagenase and elastase activities were isolated from liver homogenates. Isolated schistosome eggs did not contain collagenase or elastase activities. Collagenolytic activity had the characteristics of a tissue collagenase. These data show that marked increases in collagenase activity occur together with increased collagen synthesis in this animal model. Continued accumulation of liver collagen under these conditions suggests an imbalance between increased collagen synthesis and degradation.

A study on serum monoamine oxidase (MAO) levels in fibrotic disease processes led us to investigate patients with moderate to severe burns. Strikingly low serum MAO activity was found in patients with relatively recent, severe injuries. So far, we have no explanation to offer for the phenomena observed.

Arylsulfatases A and B were measured in the liver of mice infected with Schistosoma mansoni. The increase of total arylsulfatases paralleled enlargement of the granulomas. It began at 7 weeks after infection and reached a maximum at 10 to 14 weeks when the enzyme activity became about 2.5 times that of normal liver. The elevated enzyme activity was due to granulomatous tissue, because when granulomas were separated from hepatic cells, the former contained the increased activity but the latter did not. Arylsulfatase A, arylsulfatase B, and arylsulfatase Bv, in both normal liver and granulomas, were separated by anion-exchange column chromatography and differences in net charges of these enzymes were demonstrated by polyacrylamide gel electrophoresis. Biochemical properties were indistinguishable between arylsulfatase B and arylsulfatase Bv while they differed from arylsulfatase A. Granulomas at 8 weeks after infection showed 3.0-, 3.5-, and 5.0-fold increases in activity for arylsulfatase A, B, and Bv, respectively. As the granulomas enlarged, by 12 weeks, arylsulfatases B and Bv activities further increased but the arylsulfatase A value remained the same as that of 8 weeks. The finding suggests that arylsulfatases are involved in granuloma development and arylsulfatases B and Bv activities may reflect functions of macrophages and other cells including fibroblasts.

The activities of the enzymes SD, GD, AAT, 5'NT, GGT, LDH and CPK were determined weekly in sera of two calves each infected with 10,000 S. bovis cercariae and in two controls. In infected animals, LDH activity increased from the first week of exposure and remained high throughout the experiment (22 weeks). GGT activity increased nine weeks after exposure and remained high. CPK activity was elevated during weeks 8-15 of infection. No change was detected in the activity of the other enzymes, nor in any enzymes of the controls.

In schistosomiasis mansoni, eggs trapped in portal venules of the liver induce a granulomatous inflammatory reaction and subsequently fibrosis. Upon specific schistosomicidal treatment, however, fibrosis undergoes a marked reversal. The features of this process as regards collagen metabolism were examined in mice using praziquantel as the schistosomicidal drug, which was given 68 days after infection. It was found that collagenase activity in the liver, for both latent and active forms, increases rapidly until 5 days after treatment as compared to nontreated infected mice and then diminishes gradually. The hydroxyproline content in liver and (24-hr) urine are also modified, their values decreasing progressively up to 72 days after treatment without, however, reaching values observed in normal mice. Worm death appears to be the triggering stimulus of these events.

Four cDNA clones encoding a proteinase which facilitates skin invasion by schistosome parasites were isolated by screening a schistosome sporocyst cDNA library, using an oligonucleotide probe containing sequences complementary to predicted 5'-translated regions of its RNA. The amino acid sequence of the enzyme, as deduced from the DNA sequence of the clones, indicates that the enzyme is a serine protease which in many respects is similar to vertebrate pancreatic elastases, although regions outside of the putative active site, binding pocket, and amino-terminal cysteines differ significantly. Regulation of expression of the enzyme occurs at the level of mRNA transcription as well as posttranslationally, the latter involving the processing of a previously unidentified pre-proenzyme (zymogen) sequence. In situ hybridization of the cDNA clones to tissue sections of developing larvae indicates that the enzyme is synthesized within a discrete time frame in specialized cells of the organism.