Changes in glutathione metabolic enzymes during yeast-to-mycelium conversion of Candida albicans

1996 ◽  
Vol 42 (1) ◽  
pp. 76-79 ◽  
Author(s):  
Merlin Manavathu ◽  
Elias Manavathu ◽  
Suresh Gunasekaran ◽  
Quallyna Porte ◽  
Muthukumaran Gunasekaran
Keyword(s):  
Candida Albicans ◽  
Glutathione Peroxidase ◽  
Glutathione Reductase ◽  
Environmental Changes ◽  
Yeast Cells ◽  
Glutathione Metabolism ◽  
Glutathione S Transferase ◽  
Mycelial Form ◽  
Glutamic Acid Residue ◽  
Germ Tubes

Candida albicans is a dimorphic yeast capable of producing alternate morphological forms (yeast or mycelium) in response to environmental changes. The intracellular level of glutathione, which helps to maintain the redox potential of the cell, is decreased significantly during the thermal induction of yeast-to-mycelium conversion. The reason for the decline of glutathione in the mycelial form is not understood. We have, therefore, investigated the levels of glutathione reductase, glutathione S-transferase, γ-glutamyltranspeptidase, and glutathione peroxidase, four key enzymes involved in glutathione metabolism, in the yeast and mycelial forms. Yeast cells of C. albicans 3153A were induced in Lee's medium (pH 6.5) at 37 °C for 3 h to produce germ tubes. Cell lysates were prepared from yeast and mycelial cells, and glutathione reductase, glutathione S-transferase, γ-glutamyltranspeptidase, and glutathione peroxidase were assayed spectrophotometrically. There was a 640% increase of the level of γ-glutamyltranspeptidase in the germ tubes as compared with the yeast cells. No other significant alteration of the levels of enzymes was noted. This increased activity of γ-glutamyltranspeptidase, which cleaves the glutamic acid residue of glutathione (Glu-Cys-Gly) appears to be, at least in part, responsible for the rapid decrease of the intracellular glutathione in C. albicans during the yeast-to-mycelium conversion.Key words: Candida albicans, dimorphism, glutathione, glutathione reductase, glutathione peroxidase, γ-glutamyltranspeptidase.

scholarly journals Effect of Cross-Sex Hormonal Replacement on Antioxidant Enzymes in Rat Retroperitoneal Fat Adipocytes

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Israel Pérez-Torres ◽  
Verónica Guarner-Lans ◽  
Alejandra Zúñiga-Muñoz ◽  
Rodrigo Velázquez Espejel ◽  
Alfredo Cabrera-Orefice ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Superoxide Dismutase ◽  
Antioxidant Enzymes ◽  
Glutathione Peroxidase ◽  
Glutathione Reductase ◽  
Enzymatic Activities ◽  
Glutathione S Transferase ◽  
Control Groups ◽  
Intact Female ◽  
Hormonal Replacement

We report the effect of cross-sex hormonal replacement on antioxidant enzymes from rat retroperitoneal fat adipocytes. Eight rats of each gender were assigned to each of the following groups: control groups were intact female or male (F and M, resp.). Experimental groups were ovariectomized F (OvxF), castrated M (CasM), OvxF plus testosterone (OvxF + T), and CasM plus estradiol (CasM + E2) groups. After sacrifice, retroperitoneal fat was dissected and processed for histology. Adipocytes were isolated and the following enzymatic activities were determined: Cu-Zn superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and glutathione reductase (GR). Also, glutathione (GSH) and lipid peroxidation (LPO) were measured. In OvxF, retroperitoneal fat increased and adipocytes were enlarged, while in CasM rats a decrease in retroperitoneal fat and small adipocytes are observed. The cross-sex hormonal replacement in F rats was associated with larger adipocytes and a further decreased activity of Cu-Zn SOD, CAT, GPx, GST, GR, and GSH, in addition to an increase in LPO. CasM + E2exhibited the opposite effects showing further activation antioxidant enzymes and decreases in LPO. In conclusion, E2deficiency favors an increase in retroperitoneal fat and large adipocytes. Cross-sex hormonal replacement in F rats aggravates the condition by inhibiting antioxidant enzymes.

Glutathione peroxidase, glutathione reductase, glutathione S-transferase, and γ-glutamyltranspeptidase activities in the human early pregnancy placenta

1983 ◽  
Vol 29 (2) ◽  
pp. 143-148 ◽  
Author(s):  
Carmine Di Ilio ◽  
Giovanni Polidoro ◽  
Arduino Arduini ◽  
Antonio Muccini ◽  
Giorgio Federici
Keyword(s):  
Glutathione Peroxidase ◽  
Glutathione Reductase ◽  
Early Pregnancy ◽  
Glutathione S Transferase

The effect of dietary protein and sulfur amino acids on hepatic glutathione concentration and glutathione-dependent enzyme activities in the rat

1988 ◽  
Vol 66 (8) ◽  
pp. 1048-1052 ◽  
Author(s):  
P. F. Bauman ◽  
T. K. Smith ◽  
T. M. Bray
Keyword(s):  
Amino Acids ◽  
Glutathione Peroxidase ◽  
Glutathione Reductase ◽  
Dietary Protein ◽  
Transferase Activity ◽  
Sulfur Amino Acids ◽  
Glutathione S Transferase ◽  
Glutathione Concentration ◽  
Hepatic Glutathione ◽  
Protein Diets

Hepatic glutathione concentration and glutathione-dependent enzymes, glutathione S-transferase, glutathione peroxidase, and glutathione reductase, are important for protection against toxic compounds. Rats were fed diets containing 4, 7.5, 15, or 45% protein for 2 weeks. Glutathione and cysteine concentrations in rats fed the 4 and 7.5% protein diets were significantly lower (p < 0.05) than in rats fed the 15 and 45% protein diets. Glutathione S-transferase activity increased with increasing dietary protein. Glutathione peroxidase activity was significantly lower (p < 0.05) in rats fed 4 and 7.5% protein compared with rats fed 15 and 45% protein, whereas the activity of glutathione reductase was higher in rats fed 4 and 7.5% protein then in rats fed 15 or 45% protein. Dietary sulfur amino acids alone could account for the increase in glutathione concentration resulting from the increase in dietary protein from 7.5 to 15%. The limited availability of glutathione in animals fed the low protein diets could reduce the potential for detoxification of xenobiotics.

Differences in lung glutathione metabolism may account for rodent susceptibility in elastase-induced emphysema development

2009 ◽  
Vol 296 (4) ◽  
pp. R1113-R1123 ◽  
Author(s):  
Gisella R. Borzone ◽  
Leonel F. Liberona ◽  
Andrea P. Bustamante ◽  
Claudia G. Saez ◽  
Pablo R. Olmos ◽  
...  
Keyword(s):  
Glutathione Peroxidase ◽  
Glutathione Reductase ◽  
Diffuse Alveolar Damage ◽  
Intratracheal Instillation ◽  
Glutathione Metabolism ◽  
Oxidized Glutathione ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Glutamylcysteine Synthetase ◽  
Gsh Metabolism

Syrian Golden hamsters develop more severe emphysema than Sprague-Dawley rats after intratracheal instillation of the same dose of elastase/body weight. Although species variations in antielastase defenses may largely explain these results, other variables, such as differences in lung antioxidants, cannot be overlooked since oxidative stress modulates antiprotease activity. We propose that elastase instillation might affect lung glutathione (GSH) metabolism differently in these species. Our aim was to study in hamsters and rats, lung glutathione metabolism at different times, from the stage of diffuse alveolar damage to advanced emphysema. We measured total and oxidized glutathione content as well as activity and expression of enzymes related to GSH synthesis and redox cycling: γ-glutamylcysteine synthetase, glutathione peroxidase, and glutathione reductase. Whereas rats showed no significant changes in these measurements, hamsters showed significant derangement in GSH metabolism early after elastase instillation: 25% fall in total GSH ( P < 0.05) with no increase in oxidized glutathione associated with reduced enzyme activities 24 h after elastase [60% for γ-glutamylcysteine synthetase ( P < 0.01), 30% for glutathione peroxidase ( P < 0.01), and 75% for glutathione reductase ( P < 0.001)]. GSH homeostasis was restored at the end of the first week, involving transient increased expression of these enzymes. We conclude that elastase induces significant alterations in GSH metabolism of hamster lungs and no overall change in rat lungs. Although differences in disease severity may account for our findings, the hamster becomes vulnerable to functional inhibition of α1-antitrypsin by oxidants and thus, even more susceptible to injury than it would be, considering only its low α1-antitrypsin level.

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