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J F Koster

Publications and source records attributed to J F Koster.

At least 91 records · Page 5Linked to original sources
PubMed1984

Protective factors against oxygen free radicals and hydrogen peroxide in rheumatoid arthritis synovial fluid.

Oxygen free radicals are probably involved in the pathogenesis of rheumatoid arthritis (RA). The enzymes involved in protection against oxygen free radicals and H2O2 (superoxide dismutase, catalase, and glutathione peroxidase) were measured. Superoxide dismutase was not increased, glutathione peroxidase was slightly and catalase was strongly elevated in RA synovial fluid (SF) compared with control SF. Although these enzymes are present in SF, the activities are insufficient to protect against oxygen free radicals and H2O2. In contrast to transferrin, ferritin was increased in RA synovial fluid. Ceruloplasmin was also elevated. When rat liver microsomes were used as a target for oxygen free radicals, serum and SF were both protective. Gel filtration experiments showed that the fraction pattern in which there was maximal protective potential against lipid peroxidation corresponded closely to the level of ceruloplasmin. After removal of ceruloplasmin from serum or SF, about 70% of the protective capacity disappeared. It is concluded that ceruloplasmin is an important protector against oxygen free radicals.

Arthritis, Rheumatoid↗
PubMed1984

Iron mobilization from ferritin by superoxide derived from stimulated polymorphonuclear leukocytes. Possible mechanism in inflammation diseases.

During inflammation, the superoxide anion (O-2) and hydrogen peroxide (H2O2) are produced by stimulated polymorphonuclear leukocytes and macrophages. The toxic effects of these reactive oxygen intermediates increase when traces of iron are present, because iron catalyzes the formation of the hydroxyl radical (OH.). Partially saturated iron-binding proteins, such as transferrin and ferritin, are unable to catalyze OH. formation in vitro. Mobilization of iron from these proteins is necessary for iron stimulation of OH. formation. This paper reports that stimulated polymorphonuclear leukocytes mobilize iron from human and horse ferritin, but not from human transferrin. Iron release from ferritin depends on O-2 because it can be prevented by the addition of superoxide dismutase. Catalase and dimethylsulfoxide have no inhibitory effect on iron mobilization. The efficiency of the iron release increases at low levels of O-2 production. Only O-2 produced by granulocytes is sufficient for iron mobilization, because solid potassium superoxide is also able to release iron from ferritin. We propose that this reaction may potentiate the formation of the OH. radical in inflammatory states.

Animals↗
PubMed1983

The effect of (13 OOH) linoleic acid on human erythrocytes and on erythrocyte ghosts.

Peroxidized linoleic acid (13 OOH) induces lipid peroxidation, measured as malondialdehyde in erythrocyte ghosts and intact erythrocytes. This process can be inhibited by desferal, thiourea and butylated hydroxytoluene. During the lipid peroxidation process fluorescent chromolipids are formed. The synthesis of these chromolipids can be blocked by desferal. Peroxidized linoleic acid gives cross-linking of the proteins present in the membranes leading to the formation of higher molecular weight proteins. Also in the lower molecular weight region of SDS-electrophoresis a protein band is formed. The cross-linking process of the membrane protein is most effectively blocked by thiourea, to some extent by butylated hydroxytoluene and hardly at all by desferal. Addition of peroxidized linoleic acid to intact erythrocytes leads to a drop in the glutathione level (analogous to cumene hydroperoxide). In the presence of glucose the glutathione level can be restored.

Erythrocyte Membrane↗
PubMed1983

The effect of diethyldithiocarbamate on the lipid peroxidation of rat-liver microsomes and intact hepatocytes.

The role of the oxygen radicals in lipid peroxidation, induced by ADP/Fe3+ or cumene hydroperoxide was investigated by administering diethyldithiocarbamate, an inhibitor of superoxide dismutase, to hepatocytes or rats. Intact rat-liver hepatocytes perform a delayed ADP/Fe3+-induced lipid peroxidation after pretreatment with diethyldithiocarbamate. The cumene hydroperoxide-induced lipid peroxidation is unchanged. Hepatocytes, isolated from a rat administered with diethyldithiocarbamate in vivo, exhibit the same pattern, a delayed iron-induced lipid peroxidation and an unchanged cumene hydroperoxide-induced lipid peroxidation. Liver microsomes isolated from liver of a rat administered with diethyldithiocarbamate do not perform lipid peroxidation with NADPH/ADP/Fe3+, but do undergo lipid peroxidation with cumene hydroperoxide. It can be concluded that besides the inhibition of superoxide dismutase, diethyldithiocarbamate inhibits directly the microsomal lipid peroxidation. Although this inhibition hampers the conclusion, evidence is obtained that superoxide dismutase is probably involved in the protection against lipid peroxidation of the mitochondria, but not of the microsomes.

Adenosine Diphosphate↗
PubMed1983

Lipid peroxidation of human erythrocyte ghosts induced by organic hydroperoxides.

Isolated human erythrocyte ghosts perform lipid peroxidation, measured as malondialdehyde, induced by cumene hydroperoxide and t-butyl hydroperoxide but not by H2O2. In contrast to Ames et al. (Ames, B.N., Cathcart, R., Schwiers, E. and Hochstein, P. (1981) Proc. Natl. Acad. Sci. 78, 6858-6862), no inhibition is found by uric acid, only an increase in lag-time of the malondialdehyde production. In parallel with the malondialdehyde production, fluorescent chromolipids are also formed. Both processes are blocked by the addition of desferal, a potent iron chelator. The malondialdehyde production is also inhibited by the OH radical scavenger, thiourea, and by the anti-oxidant, butylated hydroxytoluene. Treatment of erythrocyte ghosts with cumene hydroperoxide or t-butyl hydroperoxide leads to the genesis of high-molecular-weight protein, but not with H2O2. The appearance of high-molecular-weight proteins is accompanied by disappearance of protein bands, e.g., the alpha- and beta-spectrin band, the anion-exchanger and some other smaller bands. Furthermore, a protein band is formed in the lower-molecular-weight region. 4. The addition of desferal does not reveal any blockade of the high-molecular-weight protein genesis. In contrast, a marked diminution of high-molecular-weight proteins is observed by the addition of thiourea, accompanied by a protection of the protein bands which would otherwise disappear. Similar results are obtained with butylated hydroxytoluene. 5. It is concluded that under oxidative stress the process of high-molecular-weight protein genesis can occur independently of the lipid peroxidation process, measured as the revealing of malondialdehyde.

Blood Proteins↗
PubMed1982

Canine glycogen storage disease type II. A biochemical study of an acid alpha-glucosidase-deficient Lapland dog.

A biochemical study was performed in a Lapland dog suspected of glycogen storage disease type II (acid alpha-glucosidase deficiency, Pompe's disease). Glycogen content was substantially elevated in heart and skeletal muscle but not in the liver. Severely reduced activities of acid alpha-glucosidase (EC 3.2.1.20) were found in heart, skeletal muscle, liver and cultured tongue fibroblasts. The deficiency was located in the glycoprotein fraction, which supported its lysosomal origin. The electrophorogram showed after acid incubation that the affected dog was missing the activity band, while after neutral incubation the pattern was similar to control. The obtained biochemical data are compared with the known data of the human pathology.

Animals↗
PubMed1982

On the lipid peroxidation of rat liver hepatocytes, the formation of fluorescent chromolipids and high molecular weight protein.

1. The formation of malondialdehyde by intact hepatocytes, induced by ADP/Fe3+ or cumene hydroperoxide, can be inhibited by the addition of thiourea. This may indicate that hydroxyl radicals are involved in this process. 2. Lipid peroxidation of intact hepatocytes leads to the formation of fluorescent chromolipids. When similar amounts of malondialdehyde are formed by either ADP/Fe3+ or cumene hydroperoxide, the lipid peroxidation induced by cumene hydroperoxide generates more fluorescent chromolipids than does the lipid peroxidation induced by ADP/Fe3+. 3. The formation of chromolipids is accompanied by the genesis of high molecular weight protein. With cumene hydroperoxide more high molecular weight protein is formed than with ADP/Fe3+. 4. It can be concluded that the defense system against lipid peroxidation of intact hepatocytes does not prevent the formation of lipofuscin-like chromolipids and high molecular weight protein as found earlier in microsomes. Cumene hydroperoxide, at least in this system, can be considered as an effective inducer of chromolipids.

Adenosine Diphosphate↗
PubMed1981

Identification of heterozygotes for glycogenosis 2 (acid maltase deficiency).

In 21 obligate and 9 possible heterozygotes for acid maltase deficiency (AMD) (glycogenosis 2, Pompe's disease), different methods of identifying heterozygotes have been studied. Heterozygosity could not be demonstrated by physical examination, serum CPK assays, morphological examination of muscle biopsy (including light-microscopy, histochemistry and electron-microscopy), or by ultrastructural examination of a skin biopsy. Heterozygotes could be identified to a large, but still limited extent, by measuring the acid alpha-glucosidase activity in urine, cultivated fibroblasts, leucocytes, or skeletal muscle. Heterozygotes for the generalized from of AMD could not be distinguished from those for the muscular form. The limitations of heterozygote identification by means of enzyme assays are discussed, and some practical aspects for genetic counselling are mentioned.

Female↗
PubMed1981

A family with different clinical forms of acid maltase deficiency (glycogenosis type II): biochemical and genetic studies.

In the same family, the generalized or infantile form of acid maltase deficiency (glycogenosis type II, Pompe disease) and the muscular or adult-onset form affected different individuals. Autosomal-recessive inheritance for the two clinical forms was demonstrated in this family by assay of acid alpha-glucosidase in muscle, lymphocytes, cultured fibroblasts, and urine of asymptomatic relatives. Current biochemical techniques do not discriminate between persons heterozygous for the generalized form and those heterozygous for the muscular form. To explain the coexistence of both forms in the same family, the infant with the generalized form or her grandfather with the muscular form must have been a genetic compound of different mutant alleles for acid alpha-glucosidase.

Adult↗
PubMed1980

Lipid peroxidation of rat liver microsomes.

1. The NADPH-dependent lipid peroxidation process was studied with microsomes and also the effects of addition of superoxide dismutase, catalase and thiourea. Only catalase and thiourea were able to inhibit lipid peroxidation. It seems that the initiating radical is the OH. radical formed by the Fenton reaction. 2. During lipid peroxidation glucose-6-phosphatase is inactivated, whilst the microsomal enzyme palmitoyl-CoA hydrolase is practically not affected. Because glucose-6-phosphatase activity decreases during ageing and palmitoyl-CoA hydrolase does not, a possible relationship with the ageing process is thought to exist. 3. Chromolipids are formed by the NADPH-dependent lipid peroxidation. These chromolipids have the same excitation-emission spectra as described for lipofuscin. The formation of these chromolipids is blocked by the addition of catalase and thiourea. 4. High-molecular weight proteins are formed during the NADPH-dependent lipid peroxidation. This process can be associated with the inactivation of enzymes. Also polymerisation is prevented by catalase and thiourea.

Animals↗
PubMed1980

Isoenzymes of human phosphofructokinase.

Human liver phosphofructokinase has been isolated in order to obtain antibodies against human liver phosphofructokinase. With the antiserum it could be shown in human liver that two types of phosphofructokinase exist with no subunits in common. Leucocytes, erythrocytes and kidney also possess the liver (L-) type subunit and a small amount of L-type is present in brain. There is no L-type of phosphofructokinase present in muscle and heart tissue.

Brain↗
PubMed1980

Characteristics of acid lipase and acid cholesteryl esterase activity in parenchymal and non-parenchymal rat liver cells.

(1) Parenchymal and non-parenchymal cells were isolated from rat liver. The characteristics of acid lipase activity with 4-methylumbelliferyl oleate as substrate and acid cholesteryl esterase activity with cholesteryl[1-14C]oleate as substrate were investigated. The substrates were incorporated in egg yolk lecithin vesicles and assays for total cell homogenates were developed, which were linear with the amount of protein and time. With 4-methylumbelliferyl oleate as substrate, both parenchymal and non-parechymal cells show maximal activities at acid pH and the maximal activity for non-parenchymal cells is 2.5 times higher than for parenchymal cells. It is concluded that 4-methylumbelliferyl oleate hydrolysis is catalyzed by similar enzyme(s) in both cell types. (2) With cholesteryl[1-14C]oleate as substrate both parenchymal and non-parenchymal cells show maximal activities at acid pH and the maximal activity for non-parenchymal cells is 11.4 times higher than for parenchymal cells. It is further shown that the cholesteryl ester hydrolysis in both cell types show different properties. (3) The high activity and high affinity of acid cholesteryl esterase from non-parenchymal cells for cholesterol oleate hydrolysis as compared to parenchymal cells indicate a relative specialization of non-parenchymal cells in cholesterol ester hydrolysis. It is concluded that non-parenchymal liver cells in cholesterol ester hydrolysis. It is concluded that non-parenchymal liver cells possess the enzymic equipment to hydrolyze very efficiently internalized cholesterol esters, which supports the suggestion that these cell types are an important site for lipoprotein catabolism in liver.

Animals↗
PubMed1980

Leigh's disease with decreased activities of pyruvate carboxylase and pyruvate decarboxylase.

In a patient with the clinical symptoms of Leigh's disease a partial deficiency of hepatic pyruvate carboxylase and pyruvate decarboxylase was found at necropsy. Cerebral pyruvate decarboxylase activity was also diminished. All enzyme activities were measured in total homogenates. The finding of typical necrotic lesions in the brain stem was consistent with the clinical diagnosis. During life moderate lactic acidaemia and no hypoglycaemia were observed, but an abnormal organic acid excretion pattern was present. The contribution of the enzyme defects to the aetiology of the disease is discussed.

Brain↗