Activity of gamma-glutamyl transpeptidase in serum of patients receiving anticonvulsant of anticoagulant therapy.

1. Effects of chronic anticoagulant therapy in heart patients and anticonvulsant therapy in epileptics on gamma-glutamyl transpeptidase activity in serum were investigated. 2. The enzyme was elevated in 22% of 18 patients receiving anticoagulants. In these patients prothrombin time was also abnormally high. 3. 84% of 65 epileptics exhibited elevated gamma-glutamyl transpeptidase activity, 67% of which were not associated with elevated alkaline phosphatase or aspartate aminotransferase activities. In these latter cases, involvement of the liver was not apparent. 4. Possible relationships of anticonvulsant mediated enzyme induction or hepatic toxicity to elevated gamma-glutamyl transpeptidase activity in serum in epileptics is discussed.     

Hepatic collagen proline hydroxylase activity in alcoholic liver disease.

The activity of hepatic collagen proline hydroxylase was examined in biopsy samples as a factor in collagen synthesis in 77 patients with alcoholic liver disease. The urinary excretion of peptide bound hydroxyproline was also measured in most of the patients, as an index of collagen degradation. The highest activities of collagen proline hydroxylase were found in the patients with alcoholic hepatitis. Enzyme activity was markedly increased in patients with non-specific changes on liver biopsy, whereas, patients with fatty infiltration had only mild elevations, and those with inactive cirrhosis had normal enzyme activity. Urinary hydroxyproline was elevated only in patients with alcoholic hepatitis and inactive cirrhosis. Follow-up determinations in 16 patients with alcoholic hepatitis, after 4 to 5 weeks, revealed a decrease in enzyme activity, but no change in urinary hydroxyproline. We conclude that among the types of alcohol-related liver diseases, alcoholic hepatitis is associated with the greatest turnover of hepatic collagen.     

Collagen biosynthesis enzymes in serum and hepatic tissue in liver disease

Abstract. Serum immunoreactive prolyl hydroxylase protein was measured in sixty-five patients with liver disease, and liver prolyl hydroxylase activity, immunoreactive prolyl hydroxylase protein and collagen hydroxyproline in forty of these patients. Serum immunoreactive prolyl hydroxylase protein was above the 95% confidence limit of the controls in most patients with primary biliary cirrhosis, portal cirrhosis, acute hepatitis and cancer with liver metastases, but below this in most patients with fatty liver, chronic active hepatitis, extrahepatic cholestasis, cholangitis, cancer without liver metastases and other malignant diseases. Elevated serum immunoreactive prolyl hydroxylase protein decreased rapidly with time in acute hepatitis but not in primary biliary cirrhosis. Liver prolyl hydroxylase activity and immunoreactive prolyl hydroxylase protein were elevated in the same diseases as serum immunoreactive prolyl hydroxylase protein, and correlated significantly with the latter whereas no correlation was found between serum immunoreactive prolyl hydroxylase protein and collagen hydroxyproline. Serum immunoreactive prolyl hydroxylase protein correlated highly significantly with serum alkaline phosphatase and weakly with serum aspartate aminotransferase in primary biliary cirrhosis, but not in any other disease. No correlation was found between serum immunoreactive prolyl hydroxylase protein and other tests of liver function. The results suggest that changes in serum immunoreactive prolyl hydroxylase protein in liver disease primarily reflect changes in this enzyme in the hepatic tissue, and that assays of serum immunoreactive prolyl hydroxylase in liver disease may give useful information on the actual hepatic collagen synthesis.     

Serum and liver glycylproline dipeptidyl aminopeptidase activity in rats with experimental hepatic cancer

Changes of glycylproline dipeptidyl aminopeptidase (GPDA) and gamma-glutamyl transpeptidase (gamma-GTP) activities were compared in the serum and liver tissue of rats with hepatic cancer induced by 3'-methyl DAB. Serum glycylproline dipeptidyl aminopeptidase activity in rats with the azo dye-induced hepatic cancer was significantly higher than that in healthy rats, but the increase was not so extensive compared with that of gamma-glutamyl transpeptidase. The specific activity of glycylproline dipeptidyl aminopeptidase was decrease in the microsomal fraction and increased in the supernatant fraction of hepatic cancer tissue, whereas that of gamma-glutamyl transpeptidase was increased in both microsomal and supernatant fractions. These results suggest that the mechanisms, whereby serum activities of these two enzymes were increased in rats with hepatic cancer, were different from each other.     

Serum levels of magnesium in hepatic cirrhosis

In a group of 50 patients with liver cirrhosis compared with a group of 50 clinically healthy subjects serum magnesium levels were determined. The patients were divided according the aetiology of liver cirrhosis and to the presence or not of ascite and cholestasis. The serum magnesium levels were related to the main laboratory tests used in liver cirrhosis. The patients present a significant decrease of serum magnesium levels in comparison to controls. The patients with alcoholic cirrhosis of the liver and with ascite have significant lower magnesium levels in comparison with the patients with post-hepatitis cirrhosis and with patients without ascite. There is a significant correlation between serum magnesium levels and serum levels of aldosterone, albumin, gamma-glutamyl transpeptidase and total pool of bile acids. Direct and indirect effects of alcohol, a secondary hyperaldosteronism, the use of diuretics, and hypoalbuminaemia could account for magnesium serum level decrease in liver cirrhosis.     

1-14C]Ethanol breath test in alcoholic liver disease

The activity of ethanol metabolising enzymes was assessed in 51 patients with alcoholic and non-alcoholic liver disease using tracer doses of [1-14C]ethanol and measuring 14CO2 excretion in the breath. Alcoholic patients with only fatty infiltration of the liver showed significantly increased activity compared with controls. Comparing alcoholic patients with cirrhosis and a serum albumin greater than 28 g/l, activity in those with a recent history of continued heavy drinking was significantly greater than in patients who had abstained from alcohol. In addition, both groups of alcoholic cirrhosis showed significantly more activity than patients with non-alcoholic cirrhosis. The activities of patients with acute alcoholic or viral hepatitis were normal when their prothrombin times were less than 7 sec prolonged, but were reduced when prolongation exceeded 7 sec. These results demonstrate that in chronic alcoholic liver disease, even with cirrhosis, alcohol can still increase the activity of ethanol oxidising enzymes provided hepatic function remains adequate. However, this response is lost in acute liver damage and in chronic alcoholic disease with severe hepatic dysfunction.     

Elevated level of serum Mn-superoxide dismutase in patients with primary biliary cirrhosis: possible involvement of free radicals in the pathogenesis in primary biliary cirrhosis.

Serum Mn-superoxide dismutase (Mn-SOD) was determined in patients with various liver diseases including 31 patients with primary biliary cirrhosis (PBC), 46 with hepatocellular carcinoma (HCC), 17 with liver cirrhosis (LC), 23 with chronic hepatitis (CH) and 12 patients with obstructive jaundice with an enzyme-linked immunosorbent assay using a specific monoclonal antibody. The serum level in patients with PBC (407 +/- 35 ng/ml, mean +/- SEM; n = 31) was significantly increased (p less than 0.01) compared with those of other liver diseases. Mn-SOD level did not correlate with total bilirubin level, gamma-glutamyl transpeptidase activity, alkaline phosphatase activity, alanine aminotransferase activity, IgM, or with ceruloplasmin level in the sera of the patients. When the patients with PBC were histologically subdivided into four groups according to Scheuer's classification (Scheuer PJ. Primary biliary cirrhosis. In: Scheuer PJ, ed. Liver biopsy interpretation. 3rd ed. London: Bailliere Tindall, 1980:47-56), a high level of serum Mn-SOD was noticed in the early stage as well as in the advanced stage of the disease. Immunoblot analysis confirmed the reactivity and specificity of the monoclonal antibody to the enzyme protein in the patients' sera. Immunostaining of a liver biopsy specimen from the patients with PBC revealed increased expression of the enzyme protein in damaged epithelial cells of interlobular bile ducts, bile ductules, and degenerated hepatocytes. These data suggested that free radicals including superoxide anion are possibly involved in the pathogenesis of the disease and Mn-SOD may play some role in a protection against the superoxide anion.     

Metabolism of vitamin D in patients with primary biliary cirrhosis and alcoholic liver disease

The metabolism of isotopically labelled vitamin D2 and D3 has been investigated in eight patients with primary biliary cirrhosis and in five controls. The concentration of labelled vitamin D2 was lower than that of vitamin D3 in serum of patients with primary biliary cirrhosis on days 1 and 2 after intravenous injection (P less than 0.005 and P less than 0.05, respectively) but no difference was seen in controls. Similar amounts of labelled 25-hydroxyvitamin D2 and D3 were seen in serum of the control group; the same pattern was observed in the primary biliary cirrhosis group, and no significant differences were observed between the two groups. In both control and primary biliary cirrhosis groups, the serum concentration of labelled 24,25-dihydroxyvitamin D2 exceeded that of 24,25-dihydroxyvitamin D3 (significant for controls on day 2, P less than 0.02) but concentrations in the two groups were not different. Concentrations of labelled 25,26-dihydroxyvitamin D3 were significantly higher than those of 25,26-dihydroxyvitamin D2 in the primary biliary cirrhosis group at all times and in the control group on days 2 and 3. Both 25,26-dihydroxyvitamin D2 and D3 were higher in the serum of patients with primary biliary cirrhosis than in controls (significant on day 1; P less than 0.05). Urinary excretion over days 0-3 of radioactivity from both vitamins D2 and D3 was significantly higher in the primary biliary cirrhosis group than in controls: 12.03 vs 1.80% for vitamin D2 and 8.98 vs 1.76% for vitamin D3 (P less than 0.005). Vitamin D2-derived urinary radioactivity in primary biliary cirrhosis correlated strongly with serum bilirubin (P = 0.005). The metabolism of labelled vitamin D3 was studied in seven patients with alcoholic liver disease, three of whom showed low serum concentrations of labelled 25-hydroxyvitamin D3 suggesting impaired hepatic synthesis. The 25-hydroxylation response was quantified as the relative index of 25-hydroxylation and was significantly related to two other indices of liver function. It is concluded that impaired 25-hydroxylation of vitamin D may occur in alcoholic liver disease and results from hepatocellular dysfunction. Less than the predicted amounts of 1,25-dihydroxyvitamin D3 were produced in four of the seven patients with alcoholic liver disease; this defect may be attributable in part to decreased precursor 25-hydroxyvitamin D and to poor renal function.     

Hepatic collagen proline hydroxylase activity in primary biliary cirrhosis

The enzyme collagen proline hydroxylase has been measured in liver biopsies from fourteen patients with primary biliary cirrhosis. The activity was elevated in ten of the patients, but not to the degree previously found in patients with active cirrhosis. There was no correlation between the enzyme activity and the liver copper concentration, which was elevated in all except one of those measured. This suggests that excessive collagen synthesis in PBC is not directly related to the high liver copper concentrations.     

Decreased serum selenium m alcoholics — a consequence of liver dysfunction

The serum concentration of selenium was decreased by 17 and 48% in non-cirrhotic and cirrhotic alcoholics, respectively, as compared to healthy controls. In these alcoholics the serum selenium correlated positively with the serum albumin and plasma prothrombin time and inversely with the serum bilirubin, alkaline phosphatase and γ-glutamyi transpeptidase. Abstinence from ethanol for two weeks was without effect on the serum selenium level in non-cirrhotic alcoholics and acute alcohol intake did not change the serum selenium concentration in non-alcoholic volunteers. In patients with primary biliary cirrhosis the serum concentration of selenium was similar to that in the alcoholic cirrhotics. In patients with hypoalbuminaemia of renal origin the serum selenium was normal.

In conclusion our results show that the deterioration of liver function, irrespective of its aetiology, leads to the decrease in serum selenium levels. Whether a defect in removal of lipoperoxides is associated with this decrease in serum selenium concentration remains to be decided by further studies.     

Induction of hepatic gamma-glutamyl transpeptidase in rats by repeated administration of aminopyrine

The effect of a 20-day administration of aminopyrine (600 mg kg-1) as well as two metabolites of aminopyrine, 4-aminoantipyrine (525 mg kg-1) and 4-acetamidoantipyrine (635 mg kg-1), on several hepatic, kidney and serum enzyme activities were investigated. In the aminopyrine-treated group, a pronounced induction of gamma-glutamyl transpeptidase was shown in the whole homogenate as compared to that in the hepatic microsomes. Serum gamma-glutamyl transpeptidase activity was also increased by administration of aminopyrine or 4-aminoantipyrine. No change in gamma-glutamyl transpeptidase activity was observed in kidney and hepatic cytosolic fractions. In all cases, 4-acetamidoantipyrine treatment showed no significant change in the enzyme activities tested. Under the same experimental condition, the amounts of cytochrome P-450 and b5, the activities of aminopyrine N-demethylase, aniline hydroxylase and carboxylesterase of liver microsomes were all induced in the aminopyrine- and 4-aminoantipyrine-treated rats. The activities of NADPH cytochrome c reductase and NADH ferricyanide reductase were also increased. The results in this paper support the view that repeated administration of aminopyrine induces hepatic membrane-bound enzyme, particularly, gamma-glutamyl transpeptidase activity.     

Localization of T and B cells and alpha fetoprotein in hepatic biopsies from patients with liver disease.

Peripheral blood and hepatic tissue T- and B-lymphocyte distributions, serum alpha fetoprotein (AFP) concentrations, and hepatic AFP were studied in 46 patients undergoing diagnostic percutaneous liver biopsy. The patients included 26 with alcoholic liver disease, 13 with nonalcoholic hepatitis or cirrhosis, and 7 with either normal histology or minor nonspecific changes. Serum AFP was determined by radioimmunoassay and hepatic tissue AFP by indirect immunofluorescence. Peripheral blood T lymphocytes were identified by the sheep red-cell rosette technique; and B lymphocytes by fluoresceinated anti-immunoglobulin antisera and IgG aggregates. Tissue identification of T lymphocytes was accomplished using an extensively absorbed rabbit antihuman thymocyte antiserum and indirect immunofluorescence; tissue B lymphocytes were identified using pepsin F (ab')2 fragments of rabbit IgG antibodies to human immunoglobulins. T lymphocytes predominanted in hepatic lymphoid infiltrates from patients with alcoholic liver disease (91+/-4%), whereas in patients with chronic active or chronic persistant hepatitis, viral hepatitis, or cryoptogenic cirrhosis proportions of T and B lymphocytic infiltrates were similar (50+/-15%). Hepatic tissue AFP was detected in 9 of 18 patients with alcoholic hepatitis; serum AFP concentration was increased in only 1 of these 9 patients. Tissue AFP was not observed in the remaining biopsy material nor were serum AFP concentrations increased. Peripheral blood T-cell numbers were significantly decreased in patients with alcoholic liver disease (P less than 0.01) and in nonalcoholic hepatitis or cirrhosis (P less than 0.025). A close relationship between peripheral blood T-lymphocytopenia and hepatic T-cell infiltrates was observed in patients with alcoholic liver disease; this relationship was less apparent in patients with nonalcoholic hepatitis or cirrhosis.     

Serum immunoreactive prolyl hydroxylase in liver disease

The concentration of serum immunoreactive prolyl hydroxylase (SIRPH) was measured in thirty patients with chronic active hepatitis, thirteen with primary biliary cirrhosis, four with alcoholic or idiopathic cirrhosis, and four with acute hepatitis; the values were compared with those in twenty-three control subjects. Increases in SIRPH were found in all the groups with liver diseases, individual values being highest in primary biliary cirrhosis in which about two-thirds of patients had values more than two standard deviations above the mean value in the control subjects. No correlation was found between SIRPH and other tests of liver function or some routine laboratory tests. SIRPH may reflect some hitherto unknown of unmeasured process in the diseased hepatic cells.     

Serum beta 2-microglobulin in chronic liver diseases

Serum beta 2-microglobulin was determined in 53 patients with chronic liver diseases. No elevation was shown in fatty liver due to obesity or alcoholism. Serum beta 2-microglobulin was abnormal only in 4% of the patients with chronic hepatitis. Determination of serum beta 2-microglobulin seems not useful for the differential diagnosis between chronic hepatitis and fatty liver due to obesity or alcoholism. Serum beta 2-microglobulin was elevated in 29% of the patients with alcoholic liver cirrhosis, in 41% of those with non-alcoholic liver cirrhosis, and in 75% of those with primary liver carcinoma. The average serum beta 2-microglobulin concentration was significantly higher in non-alcoholic liver cirrhosis than in alcoholic liver cirrhosis. There was a significant correlation between serum beta 2-microglobulin and gamma-globulin concentrations in liver cirrhosis.     

Total fasting serum bile acids and beta-hexosaminidase in alcoholic liver disease

Total serum bile acid levels and beta-hexosaminidase activity were studied in 22 normal subjects, 35 non-cirrhotic patients with acute alcohol intoxication, 45 patients with alcoholic liver cirrhosis and 11 patients with alcoholic liver cirrhosis and surgical portal-systemic shunts. Comparison was made with traditional liver function tests. beta-Hexosaminidase was most frequently elevated in acute alcohol intoxication (94%) while total serum bile acids were elevated in all patients with alcoholic liver cirrhosis. Total serum bile acid levels were found to discriminate most efficiently between acute alcohol intoxication and liver cirrhosis. The combined determination of serum beta-hexosaminidase and total serum bile acids is proposed for evaluating alcoholic liver disease.     

Selenium, alcohol and liver diseases

A possible pathogenetic role of selenium deficiency in alcoholic cirrhosis of the liver has previously been discussed. In the present study, serum concentrations of selenium, copper and zinc were analyzed in alcoholic cirrhosis as well as in chronic active hepatitis and primary biliary cirrhosis. The serum concentrations of selenium were consistently decreased in patients suffering from alcoholic cirrhosis. Zinc values were also low in these patients. Studies of a possible therapeutic effect of zinc and selenium supplementation are of interest. Other authors have reported increased hepatic lipoperoxidation and decreased hepatocellular glutathione levels in animals consuming ethanol. It is hypothesized that the low levels of Se and Zn, in combination with the reported glutathione depletion, makes the hepatocytes more vulnerable toward the toxicity of ethanol.     

Enzyme changes and morphometric analysis of bile ducts in experimental bile duct obstruction.

Chronic bile duct obstruction causes a marked proliferation of bile ductules within the rat liver plus an increase in the activities of hepatic gamma-glutamyl transpeptidase, 5'-nucleotidase and alkaline phosphatase. To determine if the increase in the activities of these enzymes within the liver simply reflects the increase in bile duct mass, we subjected rats to bile duct ligation for periods up to one week and compared the activities of these enzymes within liver tissue with bile duct volume, determined by morphometric analysis. The activities of two enzymes not useful in the diagnosis of chronic cholestasis, aspartate aminotransferase (GOT) and alanine aminotransferase (GPT), were also measured. There was no correlation between the proliferation of bile ductules and the activity of any of these enzymes. Bile duct volume increased 4.9-fold within 24 h after ligation and rose steadily, reaching a value of 13 times control in one week. Alkaline phosphatase activity increased 3.6-fold within 24 h after bile duct ligation and then was relatively constant. Gamma-glutamyl transpeptidase and 5'-nucleotidase activity both fell 24 h after ligation but were slightly increased after 48 h. Enzyme activities of each were almost twice control at 120 and 168 h. Alanine aminotransferase activity fell steadily during the period of bile duct ligation, while aspartate aminotransferase was unchanged. The change in gamma-glutamyl transpeptidase and 5'-nucleotidase activity within the liver cannot be due simply to hypertrophy of bile duct epithelium.     

Concanavalin A induced suppression of lymphocyte proliferation in chronic liver disease. A study of suppressor and responder populations in autologous and allogeneic systems

Abnormal T-cell regulation of lymphocyte proliferation may contribute towards tissue damaging mechanisms in chronic liver disease. We therefore studied Concanavalin A induced suppressor cell activity in T-T interaction in 47 patients with chronic liver disease, using both an autologous and an allogeneic system. In the autologous system, no differences were found between those with auto-immune chronic active hepatitis, HBsAg positive chronic active hepatitis, primary biliary cirrhosis, alcoholic liver disease and normal controls. However, several abnormalities were identified in allogeneic cultures with normal lymphocytes which allowed separate analysis of the influence of suppressor and responder cells from patients with chronic liver disease. An abnormality of the suppressor population was found in those with autoimmune chronic active hepatitis, primary biliary cirrhosis and alcoholic liver disease, while the responder population was abnormal in those with autoimmune or HBsAg positive CAH. Failure to demonstrate an abnormality in an autologous system may reflect a combined defect of suppressor and responder populations, and in this study the allogeneic system was a more sensitive index of abnormal cellular T-T interaction.     

Parameters of calcium metabolism during a pilot study of cyclosporin A in patients with symptomatic primary biliary cirrhosis.

Twelve patients with serologically and histologically defined symptomatic primary biliary cirrhosis were randomized to receive either oral cyclosporin A or vehicle placebo. The cyclosporin A-treated group had improvement in serum alkaline phosphatase and gamma-glutamyltransferase, suggesting a moderating effect on the course of the liver disease. However, other indices of the liver disease, including liver biopsies, did not show significant improvement. The purpose of this study was to examine the effect of the cyclosporin A treatment on serum indicators of bone and mineral metabolism in these patients, as in its later stages, primary biliary cirrhosis is associated with significant osteopenic bone disease. There were no significant changes in serum calcium, phosphate, magnesium, or vitamin D metabolites between the two groups. However, after one year of treatment, mean serum parathyroid hormone level was significantly lower in the cyclosporin A treatment group, and serum osteocalcin rose significantly. There were no significant changes in any parameter of mineral metabolism in the placebo group. The changes in parathyroid hormone and osteocalcin following cyclosporin A therapy suggest a reduction in the secondary hyperparathyroidism commonly seen with primary biliary cirrhosis and also an increase in bone formation, respectively. This study therefore provides preliminary evidence that cyclosporin A therapy seems to have a mild beneficial effect on the abnormalities of mineral metabolism seen with this disorder.     

Serum proteins in liver cirrhosis: effects of shunt surgery

The serum protein patterns of 38 patients with alcoholic liver cirrhosis were studied and compared with those of 15 patients with cryptogenic cirrhosis and of 18 normal volunteers. Serum prealbumin and albumin were significantly lowered in alcoholic liver cirrhosis in comparison with the normals. In liver cirrhosis, the four acute phase reactants, alpha 1-antiproteinase, orosomucoid, and haptoglobin and caeruloplasmin, showed a pattern in serum, in which alpha 1-antiproteinase was increased, orosomucoid and haptoglobin were decreased, and caeruloplasmin was normal. Immunoglobulins G, A and M were significantly elevated. IgA was significantly more elevated in patients with alcoholic disease than in patients with cryptogenic cirrhosis. The construction of a surgical portal-systemic shunt resulted in a significant decrease in serum concentrations of the acute phase reactants, while prealbumin, albumin and immunoglobulins were unaffected.