Glutathione Metabolism in Sheep Erythrocytes with High and Low Concentrations of Reduced Glutathione

1974 ◽  
Vol 2 (2) ◽  
pp. 314-317 ◽  
Author(s):  
JAMES D. YOUNG ◽  
IAN A. NIMMO ◽  
JOHN G. HALL
2009 ◽  
Vol 28 (10) ◽  
pp. 611-617 ◽  
Author(s):  
Betul Catalgol ◽  
Gül Özhan ◽  
Buket Alpertunga

Acrylamide (AA), a widely used industrial chemical, is shown to be neurotoxic, mutagenic and carcinogenic. This study was carried out to investigate the effects of different doses of AA on lipid peroxidation (LPO), haemolysis, methaemoglobin (MetHb) and antioxidant system in human erythrocytes in vitro. Erythrocyte solutions were incubated with 0.10, 0.25, 0.50 and 1.00 mM of AA at 37°C for 1 hour. At the end of the incubation, malondialdehyde (MDA), an end product of LPO, was determined by liquid chromatography (LC) while total glutathione, reduced glutathione (GSH) levels, activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) enzymes and the rates of haemolysis and MetHb were determined by spectrophotometric methods. All of the studied concentrations of AA increased MetHb formation and SOD activity, and induced MDA formation and haemolysis due to the destruction of erythrocyte cell membrane. AA caused a decrease in the activities of GSH-Px, CAT and GSH levels. However, these effects of AA were seen only at higher concentrations than AA intake estimated for populations in many countries. We suggest that LPO process may not be involved in the toxic effects of AA in low concentrations, although the present results showed that the studied concentrations of AA exert deteriorating effects on antioxidant enzyme activities, LPO process and haemolysis.


Blood ◽  
1972 ◽  
Vol 39 (5) ◽  
pp. 674-684 ◽  
Author(s):  
William N. Valentine ◽  
Helen M. Anderson ◽  
Donald E. Paglia ◽  
Ernst R. Jaffé ◽  
Patricia N. Konrad ◽  
...  

Abstract A 29-yr-old black woman was found to have a long-standing, nonspherocytic hemolytic disorder associated with a marked reduction in the activity of erythrocyte ribosephosphate pyrophosphokinase (RPK, PRPP synthetase, E.C. 2.7.6.1). Although the patient’s erythrocytes had about 50% of the average RPK activity of normal mature human erythrocytes, this level represented only about 20-30% of the activity in comparable reticulocyte-rich blood samples from patients with other types of hemolytic anemias. The concentrations of adenosine triphosphate adenosine diphosphate, adenosine monophosphate and, therefore, of total adenine nucleotides in her erythrocytes were markedly increased, even well above the levels in extracts of comparable reticulocyte-rich blood samples. ATPase activity was increased three- to fourfold, consistent with the reticulocytosis. Adenylate kinase and adenine phosphoribosyltransferase activities were normal. The activities of all enzymes of the Embden-Meyerhof and hexose monophosphate shunt pathways and enzymes related to glutathione metabolism were normal or increased, consistent with the reticulocytosis. The concentrations of glycolytic intermediates, other than adenine nucleotides, were normal. The conversion of glucose, adenosine, and inosine to lactate was normal or increased. Autohemolysis was of the Dacie Type II. The concentrations of erythrocyte-reduced glutathione were high normal or elevated. The stained blood film showed a striking degree of basophilic stippling of the erythrocytes. Studies of the erythrocytes of the patient’s only known relative, a son, have failed to reveal any hematologic or enzymatic abnormalities. A direct causal relationship between RPK deficiency, high ATP concentrations, and nonspherocytic hemolytic anemia could not be derived from data now available. The final decision as to whether the deficiency is primary and causative or is an epiphenomenon requires investigation of additional cases.


1994 ◽  
Vol 72 (1-2) ◽  
pp. 58-61 ◽  
Author(s):  
M. Stio ◽  
T. Iantomasi ◽  
F. Favilli ◽  
P. Marraccini ◽  
B. Lunghi ◽  
...  

A comprehensive study on glutathione metabolism in rat heart and liver as a function of age was performed. In the heart, reduced glutathione, total glutathione, and the glutathione redox index showed a decrease during aging, while oxidized glutathione levels increased in 5-month-old rats with respect to the young animals and remained quite constant in 14- and 27-month-old rats. In the liver, the highest levels of reduced glutathione were found in the 2-month-old rats, while oxidized glutathione reached a peak at 5 months. Glutathione-associated enzymes showed age-related changes. Glutathione peroxidase, unaffected by aging in the heart, decreased in the liver of the 27-month-old rats. In the heart and the liver, the highest values of glutathione S-transferase were found at 5 months and 27 months, respectively. Glucose-6-phosphate dehydrogenase followed a similar trend in both heart and liver. Glutathione reductase also showed the same behaviour in heart and in liver, increasing in old rats with respect to the other age groups. A decrease in γ-glutamylcysteine synthetase was found in the heart and liver of 27-month-old rats in comparison with the 2-month-old ones. In conclusion, a decreased antioxidant capability has been demonstrated in both heart and liver of old rats.Key words: glutathione metabolism, age, rat heart, rat liver.


1987 ◽  
Vol 7 (1) ◽  
pp. 23-31 ◽  
Author(s):  
José M. Estrela ◽  
Juan B. Montoro ◽  
Juan R. Viña ◽  
José Viña

Tert-butyl hydroperoxide decreases GSH and total free glutathione (GSH+2GSSG) contents of acini from lactating mammary glands. The decrease in total free glutathione can be explained by an increase in mixed disulfide formation and by excretion of GSS G to the extracellular medium, and subsequent degradation catalyzed by gamma-glutamyl transpeptidase. Low concentrations of glucose prevented the changes in glutathione levels induced by the peroxide. In the presence of extracellular ATP, glucose did not prevent these changes. However, incubations with the peroxide, did not alter the rate of other metabolic pathways by acini.


2010 ◽  
Vol 61 (1) ◽  
pp. 111-119 ◽  
Author(s):  
Petra Cvjetko ◽  
Ivan Cvjetko ◽  
Mirjana Pavlica

Thallium Toxicity in HumansThallium is a naturally occurring trace element, widely distributed in the earth's crust, but at very low concentrations. It does not have a known biological use and does not appear to be an essential element for life. It has been considered one of the most toxic heavy metals.Occasionally, there are reports on thallium poisoning as results of suicide or murder attempt or accident. The main threat to humans is through occupational exposure, environmental contamination, and accumulation in food, mainly in vegetables grown on contaminated soil. Increasing use in emerging new technologies and demanding high-tech industry constantly raise concern about exposure risk to all living organisms. Thallium is considered a cumulative poison that can cause adverse health effects and degenerative changes in many organs. The effects are the most severe in the nervous system. The exact mechanism of thallium toxicity still remains unknown, although impaired glutathione metabolism, oxidative stress, and disruption of potassium-regulated homeostasis may play a role. The lack of data about mutagenic, carcinogenic, or teratogenic effects of thallium compounds in humans calls for further research.


1986 ◽  
Vol 250 (4) ◽  
pp. E475-E479
Author(s):  
J. J. Morrissey

This study determines whether calcium affects glutathione metabolism and whether glutathione metabolism may influence parathyroid (PTH) secretion in collagenase dispersed bovine parathyroid cells. Reduced glutathione (GSH) and glutathione disulfide (GSSG) were measured fluorometrically and enzymatically while PTH secretion was determined by radioimmunoassay. The total GSH and GSSG content of parathyroid cells was found to range from 1.59 to 1.71 micrograms/mg cell protein, and this did not vary significantly with changes in extracellular calcium. An increase in the medium calcium concentration from 0.5 to 2.0 mM did, however, cause an increase in GSSG from 0.43-0.54 to 1.19-1.20 micrograms/mg protein with a concomitant decrease in GSH. The compound 2-cyclohexen-1-one was used to deplete the cells of GSH at a low-calcium medium (0.5 mM) to levels seen in high-calcium medium (2.0 mM). This treatment was found to inhibit PTH secretion in the low-calcium medium, as if the cells were incubated in high medium calcium. Both 2-cyclohexen-1-one and calcium caused a rapid decrease in reduced GSH levels and in hormone secretion. The ketone was not found to affect cellular protein synthesis, indicating that there was no nonspecific toxic effect of this treatment on the cells. These results suggest that changes in the calcium concentration of the medium affect the GSH/GSSG ratio of dispersed parathyroid cells. Changes in the GSH/GSSG ratio induced by calcium may be related to changes in PTH secretion.


1924 ◽  
Vol 6 (5) ◽  
pp. 587-596 ◽  
Author(s):  
Arnold H. Eggerth

1. Human and sheep erythrocytes, when placed in 0.01 N buffer solutions at reactions more acid than pH 5.2, undergo a progressive change in potential, becoming less electronegative or more electropositive. This change usually occurs within 2 hours at ordinary room temperatures. It did not occur when rabbit erythrocytes were used. 2. This change is due primarily to the liberation of hemoglobin from some of the cells. 3. Hemoglobin, even in very low concentrations, markedly alters the potential of erythrocytes in the more acid reactions. This is due to a combination between the electropositive hemoglobin and the erythrocytes. The effect of the hemoglobin is most marked in the more acid solutions; it occurs only on the acid side of the isoelectric point of the hemoglobin. 4. The isoelectric point of erythrocytes in the absence of salt, or in the presence of salts having both ions monovalent, occurs at pH 4.7. This confirms the observations of Coulter (1920–21). Divalent anions shift the isoelectric point to the acid side. 5. The effect of salts on the potential of erythrocytes is due to the ions of the salts, and is analogous in every way to the effect of salts on albumin-coated collodion particles, as discussed by Loeb (1922–23).


Open Medicine ◽  
2009 ◽  
Vol 4 (4) ◽  
pp. 506-511 ◽  
Author(s):  
Anna Łukaszewicz-Hussain

AbstractChlorfenvinphos is an organophosphate insecticide, posing a risk to those who are professionally involved in its production and use in agriculture, as well as to the general population. Organophosphates (OPs) are the class of insecticides, whose primary target is acetylcholinesterase (AChE) that hydrolyzes acetylcholine, a major neurotransmitter at the central and peripheral neuronal synapses. Moreover, many authors postulate that these compounds, both in acute and chronic intoxication, change the activities of antioxidative enzymes, thus leading to the enhancement of lipid peroxidation in many tissues. In the current study, animals received once a day, intragastrically with a stomach tube, 0.1ml/100g of olive oil (control groups) and oil solution of chlorfenvinphos at a dose of 0.02LD50 (0.3 mg/kg b. w.) — the experimental groups. The animals were sacrificed on day 14 or on day 28 of exposure. In the kidneys of rats, the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) as well as reduced glutathione level (GSH) were determined. Chlorfenvinphos administration resulted in increased activities of antioxidative enzymes in the kidney of rats. Renal activities of SOD, GPx and GR were more pronounced on day 28 of chlorfenvinphos exposure than on day 14. The kidney reduced glutathione level (GSH) did not change in comparison to the control level. The current experimental findings indicate that subchronic administration of chlorfenvinphos leads to an adaptive response in the kidney of rats and this response is mostly due to reduced glutathione level and glutathione metabolism.


1978 ◽  
Vol 76 (2) ◽  
pp. 439-447 ◽  
Author(s):  
B R Burchill ◽  
J M Oliver ◽  
C B Pearson ◽  
E D Leinbach ◽  
R D Berlin

Glutathione oxidants such as tertiary butyl hydroperoxide were shown previously to prevent microtubule assembly and cause breakdown of preassembled cytoplasmic microtubules in human polymorphonuclear leukocytes. The objectives of the present study were to determine the temporal relationship between the attachment and ingestion of phagocytic particles and the assembly of microtubules, and simultaneously to quantify the levels of reduced glutathione and products of its oxidation as potential physiological regulators of assembly. Polymorphonuclear leukocytes from human peripheral blood were induced to phagocytize opsonized zymosan at 30 degrees C. Microtubule assembly was assessed in the electron microscope by direct counts of microtubules in thin sections through centrioles. Acid extracts were assayed for reduced glutathione (GSH) and oxidized glutathione (GSSG), by the sensitive enzymatic procedure of Tietze. Washed protein pellets were assayed for free sulfhydryl groups and for mixed protein disulfides with glutathione (protein-SSG) after borohydride splitting of the disulfide bond. Resting cells have few assembled microtubules. Phagocytosis induces a cycle of rapid assembly followed by disassembly. Assembly is initiated by particle contact and is maximal by 3 min of phagocytosis. Disassembly after 5-9 min of phagocytosis is preceded by a slow rise in GSSG and coincides with a rapid rise in protein-SSG. Protein-SSG also increases under conditions in which butyl hydroperoxide inhibits the assembly of microtubules that normally follows binding of concanavalin A to leukocyte cell surface receptors. No evidence for direct involvement of GSH in the induction of assembly was obtained. The formation of protein-SSG, however, emerges as a possible regulatory mechanism for the inhibition of microtubule assembly and induction of their disassembly.


Biomolecules ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1418
Author(s):  
Oscar Jara ◽  
Peter J. Minogue ◽  
Viviana M. Berthoud ◽  
Eric C. Beyer

Cataracts of many different etiologies are associated with oxidation of lens components. The lens is protected by maintenance of a pool of reduced glutathione (GSH) and other antioxidants. Because gap junction channels made of the lens connexins, Cx46 and Cx50, are permeable to GSH, we tested whether mice expressing two different mutants, Cx46fs380 and Cx50D47A, cause cataracts by impairing lens glutathione metabolism and facilitating oxidative damage. Levels of GSH were not reduced in homogenates of whole mutant lenses. Oxidized glutathione (GSSG) and the GSSG/GSH ratio were increased in whole lenses of Cx50D47A, but not Cx46fs380 mice. The GSSG/GSH ratio was increased in the lens nucleus (but not cortex) of Cx46fs380 mice at 4.5 months of age, but it was not altered in younger animals. Carbonylated proteins were increased in Cx50D47A, but not Cx46fs380 lenses. Thus, both mouse lines have oxidizing lens environments, but oxidative modification is greater in Cx50D47A than in Cx46fs380 mice. The results suggest that GSH permeation through lens connexin channels is not a critical early event in cataract formation in these mice. Moreover, because oxidative damage was only detected in animals with significant cataracts, it cannot be an early event in their cataractogenesis.


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