Catalase and glutathione peroxidase are equally active in detoxification of hydrogen peroxide in human erythrocytes

Gaetani, Gian Franco; Galiano, Silvana; Canepa, Letizia; Ferraris, AM; Kirkman, HN

doi:10.1182/blood.v73.1.334.bloodjournal731334

Cited by 55 publications

(25 citation statements)

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“…How a host cell with a [GSH]/[CSSG] ratio of 27 supports parasite growth and maintain its own integrity is an intriguing puzzle. A possible explanation can be found in recent reports, which suggest that catalase may be at least as important as GSH in cellular defense against H,O, (Gaetani et al, 1989;., 1991 a). Moreover, it seems that the status of NADPH rather than that of GSH is the major determinant of RBC sensitivity to H,O, challenge (Scott et al, 1991 b).…”

Section: Discussionmentioning

confidence: 94%

“…Detoxification of H,O, in the glutathione peroxidase route is an efficient process, even at low concentrations of H,O, (Costarides et al, 1991), and is considered to be the main event at low H,O, levels (Cohen and Hochstein, 1963). More recent observations, however, suggest that glutathione peroxidase and catalase are equally effective in erythrocytes at high H,O, flows (Gaetani et al, 1989;Scott et al, 1991b). Oxidants and radicals can react directly with GSH to give superoxide radicals, which are eliminated by superoxide dismutase activity and GSSG (Munday and Winterbourn, 1989).…”

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confidence: 99%

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The Malaria Parasite Supplies Glutathione to its Host Cell — Investigation of Glutathione Transport and Metabolism in Human Erythrocytes Infected with Plasmodium Falciparum

Atamna

Ginsburg

1997

European Journal of Biochemistry

134

102

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Malaria-infected red blood cells are under a substantial oxidative stress. Glutathione metabolism may play an important role in antioxidant defense in these cells, as it does in other eukaryotes. In this work, we have determined the levels of reduced and oxidized glutathione (GSH and GSSG, respectively) and their distributions in the parasite, and in the host-cell compartments of human erythrocytes infected with the malaria parasite Plasmodium falciparum. In intact trophozoite-infected erythrocytes, [GSH] is low and [GSSG] is high, compared with the levels in normal erythrocytes. Normal erythrocytes and the parasite compartment display high GSH/GSSG ratios of 321.6 and 284.5, respectively, indicating adequate antioxidant defense. This ratio drops to 26.7 in the host-cell compartment, indicating a forceful oxidant challenge, the low ratios resulting from an increase in GSSG and a decline in GSH concentrations. On the other hand, the concentrations of GSH and GSSG in the parasite compartment remain physiological and comparable to their concentrations in normal red blood cells. This results from de novo glutathione synthesis and its recycling, assisted by the intensive activity of the hexose monophosphate shunt in the parasite. A large efflux of GSSG from infected cells has been observed, its rate being similar from free parasites and from intact infected cells. This result suggests that de novo synthesis by the parasite is the dominating process in infected cells. GSSG efflux from the intact infected cell is more than 60-fold higher than the rate observed in normal erythrocytes, and is mediated by permeability pathways that the parasite induces in the erythrocyte's membrane. The main route for GSSG efflux through the cytoplasmic membrane of the parasite seems to be due to a specific transport system and occurs against a concentration gradient. 1)-Glutamylcysteine [Glu(-Cys)] and GSH can penetrate through the pathways from the extracellular space into the host cytosol, but not into that of the parasite. This implies that the parasite membrane is impermeable to these peptides, and that the host cannot supply GSH to the parasite as suggested previously. Exogenous Glu(-Cys) is not converted into GSH in the host cell, arguing that GSH synthetase may not be functional. Compartment analysis of Mg" in infected erythrocytes revealed that the host compartment exhibits a low concentration of Mg2+ (0.5 mM) in comparison with the parasite compartment (4 mM) and the normal erythrocytes (1.5-3 mM). The drop in [Mg"] results in cessation of Glu(-Cys) synthesis, and hence of GSH synthesis in the host-cell compartment. The decrease in [Mg"] can affect other Mg2+-ATP-dependent functions, such as Na' and Ca2+ active efflux. The present investigation confirms that the host-cell compartment is oxidatively distressed, whereas the parasite is efficiently equipped with anti-oxidant means that protect the parasite from the oxidative injury. The parasite has a huge capacity for de nova synthesis of GSH and for the reduction of GSSG. Part o...

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Section: Discussionmentioning

confidence: 94%

mentioning

confidence: 99%

The Malaria Parasite Supplies Glutathione to its Host Cell — Investigation of Glutathione Transport and Metabolism in Human Erythrocytes Infected with Plasmodium Falciparum

Atamna

Ginsburg

1997

European Journal of Biochemistry

134

102

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“…For example, accumulation of soluble sugar was shown to be related to the acquisition of heat tolerance in sugarcane Ghazanfar 2006, Wahid andClose 2007). More importantly, increased concentration of sugar could be a natural response to protect against oxidative damage by strengthening the antioxidant system, because soluble sugar can feed NADPH-producing metabolic pathways such as the oxidative pentose-phosphate (OPP) pathway, which contribute to ROS-scavenging (Gaetani et al 1989, May et al 1998. Also, glucose has been shown to enhance cellular defences against the cytotoxicity of hydrogen peroxide in certain mammalian cell types (Averill-Bates and Przybytkowski 1994).…”

Section: Discussionmentioning

confidence: 99%

Heat Stress Effects are Stronger on Spikelets Than on Flag Leaves in Rice Due to Differences in Dissipation Capacity

Zhang

Yang

et al. 2015

J Agronomy Crop Science

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Rice is most sensitive to heat stress at the flowering stage, with different degrees of heat damage in spikelets and leaves. To investigate the heat damage in spikelets and flag leaves, two rice genotypes, N22 (heat‐tolerant) and GT937 (heat‐sensitive), were subjected to a heat‐stress treatment (40 °C for 15 days). The results showed that more damaging was found in spikelets than in flag leaves and the heat stress significantly decreased the seed‐setting rate by 12.41 % in N22 and by 65.02 % in GT937. However, the difference in the net photosynthetic rate of the flag leaf between heat‐stressed and control was not significant. Moreover, the difference of temperatures in spikelets and flag leaves was attributed to the differences in heat dissipating. Under heat stress, the transpiration rate was significantly higher in flag leaves than in spikelets, and the temperature in flag leaves were at least 4 °C cooler than in spikelets. Although the spikelet temperatures did not differ significantly between the two genotypes under heat stress, spikelets of GT937 were more severely damaged than those of N22, which might result from the differences in the antioxidant capacities between genotypes. Results showed that little difference of superoxide dismutase, peroxidase and catalase activities of spikelets was found in N22, while significant reduction was found in GT937 under heat stress, compared with control. These results suggest that organ temperature is controlled mainly by transpirational cooling, and that heat stress is an indirect result of oxidative stress, rather than a direct result of heat damage.

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“…Supplementation with vitamin E was found to induce the activity of glucose-6-phosphate dehydrogenase (G-6-PDH) and glutathione reductase in this study. Glutathione reductase is the enzyme that converts GSSG to GSH, with the help of NADPH, which is supplied by G-6-PDH (Gaetani et al 1989). This may also be a reason for the increased level of GSH observed in vitamin Esupplemented rats.…”

Section: Discussionmentioning

confidence: 99%

Vitamin E prevents buthionine sulfoximine-induced biochemical disorders in the rat

Rajasekaran

Devaraj

2004

Journal of Pharmacy and Pharmacology

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Antioxidant therapy can improve the protection and metabolic activity of cells and tissues. In this study, the effect of vitamin E administration on buthionine sulfoximine (BSO)-induced glutathione (GSH) depletion in the rat lung and liver was investigated. Hepatic GSH was depleted by intraperitoneal administration of BSO (4 mmol kg(-1)), twice a day, for 30 days to rats. We also investigated whether the lung and liver mitochondrial GSH contents were influenced by BSO administration and whether an extracellular supply of vitamin E could prevent the changes caused by BSO-mediated GSH depletion. Glutathione levels in lung and liver tissues were depleted by 47% and 60%, respectively. Depletion of hepatic and pulmonary GSH in turn causes decline in the levels of mitochondrial GSH, leading to impaired antioxidant defence function of mitochondria. Both the cytosolic and mitochondrial glutathione disulfides (GSSG) were altered during BSO treatment, and led to drastic increase in GSSG/GSH redox status. One of the experimental groups was given vitamin E (65 mg (kg diet)(-1)) mixed with rat feed. The rats fed with vitamin E were found to have partially restored GSH levels in liver and lung, diminished levels of TBARS and minimized tissue damage. The current findings suggest that the impaired glutathione and glutathione-dependent enzyme status may be correlated with the elevated lipid peroxidation and mitochondrial membrane damage and that vitamin E therapy to the BSO-administered rats prevents the above changes. However, vitamin E did not have any effect on the activity of gamma-glutamyl cysteine synthetase (gamma-GCS).

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Catalase and glutathione peroxidase are equally active in detoxification of hydrogen peroxide in human erythrocytes

Cited by 55 publications

References 0 publications

The Malaria Parasite Supplies Glutathione to its Host Cell — Investigation of Glutathione Transport and Metabolism in Human Erythrocytes Infected with Plasmodium Falciparum

The Malaria Parasite Supplies Glutathione to its Host Cell — Investigation of Glutathione Transport and Metabolism in Human Erythrocytes Infected with Plasmodium Falciparum

Heat Stress Effects are Stronger on Spikelets Than on Flag Leaves in Rice Due to Differences in Dissipation Capacity

Vitamin E prevents buthionine sulfoximine-induced biochemical disorders in the rat

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