ABSTRACT
The purpose of this study was to determine the level of methemoglobin in the blood and osmoresistance of erythrocytes in patients with different types of goiter and control subjects. Investigated parameters indicate to the antioxidant status of human organism. We examined 12 healthy controls and 49 hyperthyroid patients: 17 patients with nodular goiter (mild thyrotoxicosis), 22 patients with diffuse toxic goiter (high level of thyrotoxicosis) and 10--with euthyroid nodule goiter. Osmoresistance of erythrocytes was measured by differential photoelectrocolorymetric method and methemoglobin--by spectroscopic method. We had received significant correlation between the level of methemoglobin, osmoresistance of erythrocytes and the degree of thyrotoxicosis. The results once again prove sensitivity of antioxidant status in response to toxicity, in particular against thyrotoxicosis.
Subject(s)
Erythrocytes/metabolism , Goiter/metabolism , Goiter/physiopathology , Methemoglobin/metabolism , Osmotic Pressure , Adult , Aged , Erythrocyte Membrane/metabolism , Female , Humans , Male , Membrane Potentials , Middle AgedABSTRACT
Influence of different doses of 4-nitrophenol on some biochemical and morphological indices of rat blood was studied. Glucose and beta-lipoprotein concentration increased, but total protein concentration decreased in response to intraperitoneal injection of xenobiotic. As a result of xenobiotic action, the total amount of leukocytes and thrombocytes increased, while the amount of erythrocytes decreased. The morphological study of structural indices of blood formed elements has demonstrated, that intensity of the defensive response of blood formed elements was 4-nitrophenol dose-dependent.
Subject(s)
Blood Glucose/metabolism , Environmental Illness/blood , Lipoproteins, LDL/blood , Nitrophenols/toxicity , Animals , Blood Glucose/drug effects , Blood Platelets/drug effects , Disease Models, Animal , Dose-Response Relationship, Drug , Environmental Illness/chemically induced , Erythrocytes/drug effects , Injections, Intraperitoneal , Leukocytes/drug effects , Lipoproteins, LDL/drug effects , Male , Nitrophenols/administration & dosage , RatsABSTRACT
The aim of the work was to study the level of vitamins C, B12 and folic acid in latent iron deficiency of different etiology (hipo- and anacid gastritis and menorrhagia). 81 patients with latent iron deficiency were investigated. Vitamin C levels were measured by refractometry, folic acid and vitamin B12 by radioimmune assay. The obtained results showed significant decrease of ascorbic acid and less apparent decrease of folic acid in the blood plasma. The content of vitamin B12 was unchanged. Decrease of vitamin C level is related to the changes of initial stages of iron metabolism and its further absorption. Less apparent changes of folic acid and vitamin B12 indicates, that such important stages of erithropoesis as DNA replication and cell proliferation are intact. Our results indicate to the development of metabolic disorders prior to revelation of iron deficiency anaemia, which need timely correction.
Subject(s)
Anemia, Iron-Deficiency/drug therapy , Ascorbic Acid/therapeutic use , Folic Acid/therapeutic use , Vitamin B 12/therapeutic use , Adolescent , Adult , Aged , Female , Humans , Male , Middle AgedABSTRACT
Preincubation of submitochondrial particles (SMP) from beef heart in a reaction mixture containing low concentrations of Mg2+ induces a time lag in the NADH:oxidase activity. Preconditioning of the SMP by NADH, but not by NAD+, prevents the Mg2+-related time lag. The data obtained show that there exists a tight binding site for Mg2+ regulating the rate of electron transfer from NADH to the natural acceptor. The ability of Mg2+ to form a catalytically inactive complex with the enzyme is regulated by NADH.
Subject(s)
Magnesium/metabolism , Mitochondria, Heart/enzymology , NAD/metabolism , Quinone Reductases/metabolism , Submitochondrial Particles/enzymology , Animals , Cattle , Kinetics , Models, Theoretical , NAD(P)H Dehydrogenase (Quinone) , Oxidation-ReductionABSTRACT
A simple procedure for preparation of highly purified soluble succinate-ubiquinone reductase from bovine heart mitochondrial particles is described. The enzyme exhibits four major bands on sodium dodecyl sulfate gel electrophoresis and contains (nmol per mg protein): covalently bound flavin, 6; non-heme iron, 53; acid-labile sulfur, 50; cytochrome b-560 heme, 1.2. The enzyme catalyzes thenoyltrifluoroacetone, or carboxin-sensitive (pure non-competitive with Q2) reduction of Q2 by succinate with a turnover number close to that in parent submitochondrial particles. The succinate reduced enzyme exhibits ferredoxin-type iron-sulfur center EPR-signal (g = 1.94 species) and a semiquinone signal (g = 2.00). An oxidized preparation shows a symmetric signal centered around g = 2.01. An unusual dissociation of the enzyme in the absence of a detergent is described. When added to the assay mixture from a concentrated protein-detergent solution, the enzyme does not reduce Q2 being highly reactive towards ferricyanide ('low Km ferricyanide reactive site'; Vinogradov, A.D., Gavrikova, E.V. and Goloveshkina, V.G. (1975) Biochem. Biophys. Res. Commun. 65, 1264-1269). The ubiquinone reductase, not the ferricyanide reductase was observed when the enzyme was added to the assay mixture from the diluted protein-detergent solutions. Thus the dissociation of succinate dehydrogenase from the complex occurs in the absence of a detergent dependent on the concentration of the protein-detergent complex in the stock preparation where the samples for the assay are taken from. An active antimycin-sensitive succinate-cytochrome c reductase was reconstituted by admixing of the soluble succinate-ubiquinone reductase and the cytochrome b-c1 complex, i.e., from the complexes which both contain the ubiquinone reactivity conferring protein (QPs). Cytochrome c reductase was also reconstituted from the succinate-ubiquinone reductase and succinate-cytochrome c reductase containing inactivated succinate dehydrogenase. The reconstitution experiments suggest that there exists a specific protein-protein (or lipid) interaction between QPs and a certain component(s) of the b-c1 complex.
Subject(s)
Mitochondria, Heart/enzymology , Multienzyme Complexes/metabolism , Oxidoreductases/metabolism , Succinate Dehydrogenase/metabolism , Animals , Binding Sites , Cattle , Electron Spin Resonance Spectroscopy , Electron Transport Complex II , Electrophoresis, Polyacrylamide Gel , Flavins/analysis , Heme/analysis , Iron/analysis , Kinetics , Multienzyme Complexes/isolation & purification , Octoxynol , Oxidation-Reduction , Oxidoreductases/isolation & purification , Polyethylene Glycols/pharmacology , Spectrophotometry , Substrate Specificity , Succinate Dehydrogenase/isolation & purification , Succinates/metabolism , Succinic Acid , Sulfur/analysis , Ubiquinone/analysis , Ubiquinone/metabolismABSTRACT
Treatment of the soluble ubiquinone-deficient succinate: ubiquinone reductase with pyridoxal phosphate results in the inhibition of the carboxin-sensitive ubiquinone-reductase activity of the enzyme. The inactivation is prevented by the soluble homolog of ubiquinone (Q2) but is insensitive to the dicarboxylates interacting with the substrate binding site of succinate dehydrogenase. The reactivity of the pyridoxal phosphate-inhibited enzyme with different electron acceptors suggests that the observed inhibition is due to the dissociation of succinate dehydrogenase from the enzyme complex. The soluble succinate dehydrogenase was recovered in the supernatant after treatment of the insoluble succinate: ubiquinone reductase with pyridoxal phosphate. The data obtained strongly suggest the participation of amino groups in the interaction between succinate dehydrogenase and the ubiquinone reactivity conferring peptide within the complex.
