a(CHEBI:"hydrogen peroxide")
We found that CA (lane 4) and EC (lane 6) substantially prevented the H2O2 induced formation of the high molecular weight species. PubMed:23531502
We found that CA (lane 4) and EC (lane 6) substantially prevented the H2O2 induced formation of the high molecular weight species. PubMed:23531502
We found that CA (lane 4) and EC (lane 6) substantially prevented the H2O2 induced formation of the high molecular weight species. PubMed:23531502
Primary cortical neurons exposed to the mitochondrial toxin NaN3 (0.1-3 mM) were submitted to oxidative stress with H2O2 (30-150 μM), to mimic conditions observed in neurodegenerative disorders. The effects of such treatment on a series of parameters useful in characterizing neuronal damage were investigated: (i) the basal release of glutamate, evaluated as (3)H-d-Aspartate efflux, was sharply, concentration-dependently, increased; (ii) the phosphorylation status of intracellular markers known to be involved in the neurodegenerative processes, in particular in Alzheimer disease: tau and GSK3β were increased, as well as the protein level of β-secretase (BACE1) and p35/25 evaluated by Western blotting, while (iii) the cell metabolic activity, measured with the MTT method, was reduced, in a concentration- and time-dependent manner. The latter effect, as well as tau hyperphosphorylation, was prevented both by a mixture of antioxidant drugs (100 μM ascorbic acid, 10 μM trolox, 100 μM glutathione) and by the anti-Alzheimer drug, memantine, 20 μM. PubMed:23722080
As shown in Figure 3, the level of heme degradation is highly correlated with the level of metHb in RBCs (R = 0.6233, p < 0.0177) supporting the hypothesis that the heme degradation product formed in PRDX2 knockout mice is associated with the un-scavenged H2O2 generated during Hb autoxidation. PubMed:23215741
However, metHb levels may increase when there is an increase in Hb autoxidation and the concomitant generation of H2O2 that is not scavenged by antioxidant defense enzymes making it more difficult for metHb-reductase to keep up with the metHb produced. PubMed:23215741
Monzani et al. [10] also concluded that the heme-SA complex promotes H2O2 activation processes that bear the characteristics of enzymatic reactions and may have biological relevance. PubMed:30324533
The appreciable increase in heme degradation for RBCs from PRDX2 knockout mice in the presence of azide indicates that PRDX2 plays a major role in scavenging H2O2 in the absence of catalase, even with GPx present. PubMed:23215741
GPx removes both H2O2 and organic hydroperoxides [8,31] whereas PRDX2 removes H2O2 [2], organic hydroperoxides, lipid hydroperoxides, [32,33] peroxynitrite [34] and protein hydroperoxides [35]. PubMed:23215741
The in vivo effects that we have observed for PRDX2 knockout mice (Figures 1–4) imply that PRDX2 plays an important role in neutralizing the H2O2 generated in vivo (Figure 6). PubMed:23215741
Peroxiredoxin-2 (Prx-2) has emerged as the critical antioxidant protecting RBCs from H2O2 produced endogenously (by Hb autoxidation and subsequent superoxide dismutation) and exogenously (e.g., from activated neutrophils) at low (physiologic) concentrations (11, 32, 38, 40, 43, 45) and, therefore, may limit oxidative injury to other cells/tissues in the vasculature (6, 57). PubMed:25264713
The potential significance of this finding is underscored by the fact that Prx-2 is considered the primary antioxidant system to negate H2O2-mediated oxidative damage in the RBC (41). PubMed:25264713
Prx-2 has emerged as the key antioxidant protein that protects RBCs against biologically relevant concentrations of H2O2 produced endogenously (via hemoglobin autoxidation) or exogenously by inflammatory cells25,26. PubMed:26202471
Figure 1B presents these data and shows that (i) basal (time 0) Prx-2 oxidation was higher at day 35 relative to day 14 and 28 ( p < 0.05 by one-way analysis of variance (ANOVA) with Tukey post hoc test); (ii) H2O2 significantly increased Prx-2 oxidation, which was maximal at the first time point (5 min) measured; (iii) the magnitude of the maximal level of Prx-2 oxidation increased with RBC storage age ( p < 0.05 by one-way ANOVA with Tukey post hoc test for day 7 vs. 35 for 5 min data); and (iv) dimeric Prx-2 was slowly reduced back to the monomer over 60 min; however, this was not observed with day 35 RBC, where Prx- 2 remained > 75% oxidized. PubMed:25264713
GPx removes both H2O2 and organic hydroperoxides [8,31] whereas PRDX2 removes H2O2 [2], organic hydroperoxides, lipid hydroperoxides, [32,33] peroxynitrite [34] and protein hydroperoxides [35]. PubMed:23215741
The finding that GPx has a greater role in the inhibition of heme degradation products than catalase [3] is consistent with the primary role of catalase to react with the high concentrations of H2O2 coming from exogenous sources and for GPx to react with the low levels of H2O2 coming from the endogenous autoxidation of Hb [39]. PubMed:23215741
Finally, slower Prx-2 reduction correlated with increased H2O2 (10 lM)-induced hemolysis of day 35 RBC compared with day 7 RBC (Fig. 1D). PubMed:25264713
Overexpression of Parkin can rescue cells from the UPR elicited by a variety of stresses, such as exposure to H2O2, DNA alkylating agents, short-wavelength UV light, high osmolarity, and heat shock (Imai et al., 2000) PubMed:14556719
We found that CA (lane 4) and EC (lane 6) substantially prevented the H2O2 induced formation of the high molecular weight species. PubMed:23531502
Primary cortical neurons exposed to the mitochondrial toxin NaN3 (0.1-3 mM) were submitted to oxidative stress with H2O2 (30-150 μM), to mimic conditions observed in neurodegenerative disorders. The effects of such treatment on a series of parameters useful in characterizing neuronal damage were investigated: (i) the basal release of glutamate, evaluated as (3)H-d-Aspartate efflux, was sharply, concentration-dependently, increased; (ii) the phosphorylation status of intracellular markers known to be involved in the neurodegenerative processes, in particular in Alzheimer disease: tau and GSK3β were increased, as well as the protein level of β-secretase (BACE1) and p35/25 evaluated by Western blotting, while (iii) the cell metabolic activity, measured with the MTT method, was reduced, in a concentration- and time-dependent manner. The latter effect, as well as tau hyperphosphorylation, was prevented both by a mixture of antioxidant drugs (100 μM ascorbic acid, 10 μM trolox, 100 μM glutathione) and by the anti-Alzheimer drug, memantine, 20 μM. PubMed:23722080
Primary cortical neurons exposed to the mitochondrial toxin NaN3 (0.1-3 mM) were submitted to oxidative stress with H2O2 (30-150 μM), to mimic conditions observed in neurodegenerative disorders. The effects of such treatment on a series of parameters useful in characterizing neuronal damage were investigated: (i) the basal release of glutamate, evaluated as (3)H-d-Aspartate efflux, was sharply, concentration-dependently, increased; (ii) the phosphorylation status of intracellular markers known to be involved in the neurodegenerative processes, in particular in Alzheimer disease: tau and GSK3β were increased, as well as the protein level of β-secretase (BACE1) and p35/25 evaluated by Western blotting, while (iii) the cell metabolic activity, measured with the MTT method, was reduced, in a concentration- and time-dependent manner. The latter effect, as well as tau hyperphosphorylation, was prevented both by a mixture of antioxidant drugs (100 μM ascorbic acid, 10 μM trolox, 100 μM glutathione) and by the anti-Alzheimer drug, memantine, 20 μM. PubMed:23722080
Previous find- ings have identified ROS as a common denominator of NF-κB activating signals, as Chetsawang B found that NF-κB was increased in H 2 O 2 -treat- ed SH-SY5Y cells [22,23]. PubMed:27288790
Omega-6 phospholipids, e.g. dilinoleoylphosphatidylcholine (DLPC), have been shown to block TNF-α and H 2 O 2 activation of MAPK as well as blocks IκBα phosphorylation in the SH-SY5Y cells and prevents the phosphorylation and activation of NF-κB. PubMed:27288790
What's more, DLPC complete- ly abolishes TNF-α and H 2 O 2 induced neuronal tau phosphorylation, re- duces cellular APP levels and Aβ expression and secretion in SH-SY5Y cells [91,92] (Table 1). PubMed:27288790
However, metHb levels may increase when there is an increase in Hb autoxidation and the concomitant generation of H2O2 that is not scavenged by antioxidant defense enzymes making it more difficult for metHb-reductase to keep up with the metHb produced. PubMed:23215741
As shown in Figure 3, the level of heme degradation is highly correlated with the level of metHb in RBCs (R = 0.6233, p < 0.0177) supporting the hypothesis that the heme degradation product formed in PRDX2 knockout mice is associated with the un-scavenged H2O2 generated during Hb autoxidation. PubMed:23215741
The appreciable increase in heme degradation for RBCs from PRDX2 knockout mice in the presence of azide indicates that PRDX2 plays a major role in scavenging H2O2 in the absence of catalase, even with GPx present. PubMed:23215741
GPx removes both H2O2 and organic hydroperoxides [8,31] whereas PRDX2 removes H2O2 [2], organic hydroperoxides, lipid hydroperoxides, [32,33] peroxynitrite [34] and protein hydroperoxides [35]. PubMed:23215741
The in vivo effects that we have observed for PRDX2 knockout mice (Figures 1–4) imply that PRDX2 plays an important role in neutralizing the H2O2 generated in vivo (Figure 6). PubMed:23215741
Peroxiredoxin-2 (Prx-2) has emerged as the critical antioxidant protecting RBCs from H2O2 produced endogenously (by Hb autoxidation and subsequent superoxide dismutation) and exogenously (e.g., from activated neutrophils) at low (physiologic) concentrations (11, 32, 38, 40, 43, 45) and, therefore, may limit oxidative injury to other cells/tissues in the vasculature (6, 57). PubMed:25264713
GPx removes both H2O2 and organic hydroperoxides [8,31] whereas PRDX2 removes H2O2 [2], organic hydroperoxides, lipid hydroperoxides, [32,33] peroxynitrite [34] and protein hydroperoxides [35]. PubMed:23215741
The finding that GPx has a greater role in the inhibition of heme degradation products than catalase [3] is consistent with the primary role of catalase to react with the high concentrations of H2O2 coming from exogenous sources and for GPx to react with the low levels of H2O2 coming from the endogenous autoxidation of Hb [39]. PubMed:23215741
Once intercalated into cellular plasma membranes heme amplifies cellular susceptibility to oxidative-mediated injury by oxidants such as H2O2 or those derived from activated inflammatory cells (Balla et al., 1991a,b, 1993). PubMed:24904418
Figure 1B presents these data and shows that (i) basal (time 0) Prx-2 oxidation was higher at day 35 relative to day 14 and 28 ( p < 0.05 by one-way analysis of variance (ANOVA) with Tukey post hoc test); (ii) H2O2 significantly increased Prx-2 oxidation, which was maximal at the first time point (5 min) measured; (iii) the magnitude of the maximal level of Prx-2 oxidation increased with RBC storage age ( p < 0.05 by one-way ANOVA with Tukey post hoc test for day 7 vs. 35 for 5 min data); and (iv) dimeric Prx-2 was slowly reduced back to the monomer over 60 min; however, this was not observed with day 35 RBC, where Prx- 2 remained > 75% oxidized. PubMed:25264713
Finally, slower Prx-2 reduction correlated with increased H2O2 (10 lM)-induced hemolysis of day 35 RBC compared with day 7 RBC (Fig. 1D). PubMed:25264713
Prx-2 has emerged as the key antioxidant protein that protects RBCs against biologically relevant concentrations of H2O2 produced endogenously (via hemoglobin autoxidation) or exogenously by inflammatory cells25,26. PubMed:26202471
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If you find BEL Commons useful in your work, please consider citing: Hoyt, C. T., Domingo-Fernández, D., & Hofmann-Apitius, M. (2018). BEL Commons: an environment for exploration and analysis of networks encoded in Biological Expression Language. Database, 2018(3), 1–11.