Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We tested the hypothesis that the NAD(P)H oxidase-dependent generation of superoxide anion (O2-*) mediates tumor necrosis factor-alpha (TNF)-induced alterations in the permeability of pulmonary microvessel endothelial monolayers (PMEM). The permeability of PMEM was assessed by the clearance rate of Evans blue-labeled albumin. The NAD(P)H oxidase subcomponents p47phox and p22phox were assessed by immunofluorescent microscopy and Western blot. The reactive oxygen species O2-* was measured by the fluorescence of 6-carboxy-2',7'-dichlorodihydrofluorescein diacetatedi(acetoxymethyl ester), 5 (and 6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate-acetyl ester, and dihydroethidium. TNF treatment (50 ng/ml for 4.0 h) induced 1) p47phox translocation, 2) an increase in p22phox protein, 3) increased localization of p47phox with p22phox, 4) O2-* generation, and 5) increased permeability to albumin. p22phox antisense oligonucleotide prevented the TNF-induced effect on p22phox, p47phox, O2-*, and permeability. The scrambled nonsense oligonucleotide had no effect. The TNF-induced increase in O2-* and permeability to albumin was also prevented by the O2-* scavenger Cu-Zn superoxide dismutase (100 U/ml). The results indicate that the activation of NAD(P)H oxidase, via the generation of O2-*, mediates TNF-induced barrier dysfunction in PMEM.
Am J Physiol Lung Cell Mol Physiol 2004 Jan
PMID:NAD(P)H oxidase mediates the endothelial barrier dysfunction induced by TNF-alpha. 1280 99

Glutamate loading has been shown to protect single isolated perfused cardiomyocytes against metabolic inhibition and wash-off. The mechanism underpinning this protection is unknown. This study aimed to investigate whether reactive oxygen species (ROS) are generated by single isolated perfused cardiomyocytes and whether the protective effect of glutamate loading on cell metabolism is linked to ROS. Single rat cardiomyocytes were isolated with or without glutamate to stimulate glutamate loading. ROS production was measured using 5-(and-6)-chloromethyl-2', 7'-dichlorodihydrofluorescein diacetate in various stressful conditions including metabolic inhibition and wash-off with/without antimycin A or myxothiazol; simulated ischaemia (without cyanide) and glucose reintroduction; and H(2)O(2) perfusion. Reduced glutathione (GSH) levels were measured in control and glutamate-loaded cells with/without exposure to H(2)O(2). Finally, the effect of glutamate on glutathione reductase and glutathione peroxidase activity was measured. In every stressful condition studied, ROS production was significantly lower in glutamate-loaded cells compared to controls. This occurred regardless of whether ROS were produced intracellularly (e.g. from the respiratory chain inhibited with antimycin A) or via the extracellular precursor H(2)O(2). Glutamate-loaded cells also maintained their morphological integrity at higher H(2)O(2) concentrations than control cells. Furthermore, during H(2)O(2) exposure GSH levels decreased in glutamate-loaded cells but stayed constant in control cells. Glutamate stimulated the activity of glutathione peroxidase in a concentration-dependent fashion. These results provide new evidence to show that the cardioprotective effect of glutamate loading may be mediated through an enhanced ability to destroy ROS in the cell.
J Mol Cell Cardiol 2003 Aug
PMID:Glutamate loading protects freshly isolated and perfused adult cardiomyocytes against intracellular ROS generation. 1287 84

In our previous study, we examined reactive oxygen species (ROS) formation in T lymphocytes following 5 Gy of irradiation. Using a CCD camera system, we monitored fluorescence in T lymphocytes loaded with the succinimidyl ester of Dichlorodihydrofluorescein diacetate (H2DCFDA), which is non-fluorescent until oxidized by ROS. We found that ROS formation occurred immediately after irradiation, continued for several hours, and resulted in oxidative DNA damage. Therefore, the origin of the hyper-radiosensitivity of T lymphocytes seemed to be the high production of ROS in the mitochondrial DNA following irradiation. In this study, we examined radiation-induced ROS formation, oxidative DNA damage, early apoptotic changes, and mitochondrial membrane dysfunction in the human osteosarcoma cell line HS-Os-1, which was established from an osteoblastic tumor that arose in the left humerus of an 11-year-old girl and was already morphologically characterized in vitro and in vivo. We found that ROS formation and oxidative DNA damage were actually scarcely seen after irradiation of up to 30 Gy in these cells; that mitochondrial membrane potential was preserved; and that apoptotic changes were not demonstrated despite the relatively high-dose irradiation of 30 Gy. Therefore, the origin of the close similarity of radiosensitivity between adult articular chondrocytes and the human osteosarcoma cell line HS-Os-1, is considered to involve the low degree of ROS formation following irradiation; the similarity possibly results from the strong scavenging ability of these two kinds of cells for free radicals including hydroxyl radicals.
Int J Mol Med 2003 Oct
PMID:Mechanism of apoptotic resistance of human osteosarcoma cell line, HS-Os-1, against irradiation. 1296 18

Nitric oxide (NO) has been suggested to play a role in the hypersensitive response (HR). Single- and double-label fluorescence microscopy experiments were conducted using Arabidopsis leaves infected with Pseudomonas syringae pv. tomato DC3000 carrying either avrB or avrRpt2. Kinetics of NO production were followed by measurement of green 4-amino-5-methylamino-2',7'-difluorofluorescein (DAF-FM) triazole fluorescence in leaves coinfiltrated with DAF-FM diacetate. Kinetics of hypersensitive cell death were followed by measurement of cytoplasmic red fluorescence following internalization of coinfiltrated propidium iodide through compromised plasma membranes. Neither NO accumulation nor cell death was seen until approximately 3 h postinoculation of Columbia leaves with DC3000.avrB or approximately 5.5 h post-inoculation with DC3000.avrRpt2. Subsequent NO accumulation kinetics closely paralleled HR progression in both Columbia and ndr1-1 mutant plants. These data established that NO accumulation does not happen sufficiently early for NO to be a signaling component controlling HR triggering. NO accumulation did contribute to the HR, as proven by an approximately 1-h delay in cell death kinetics caused by an NO scavenger or an NO synthase inhibitor. NO was first seen as punctate foci at the cell surface. Subsequent NO accumulation patterns were consistent with NO being an intercellular signal that functions in cell-to-cell spread of the HR.
Mol Plant Microbe Interact 2003 Nov
PMID:Nitric oxide does not trigger early programmed cell death events but may contribute to cell-to-cell signaling governing progression of the Arabidopsis hypersensitive response. 1460 64

We investigated the effects of heat shock on developmental competence of bovine embryos and intracellular oxidative state. After in vitro fertilization, embryos were exposed to heat shock at 41 degrees C for 6 hr on days 0, 2, 4, and 6, respectively. On day 2, cleavage rate was not significantly different in all groups. However, the percentage of embryos developing to blastocyst stage after exposure to heat shock on day 0 (18.8 +/- 4.3%) and day 2 (23.6 +/- 3.7%) were significantly decreased compared with control (37.5 +/- 4.0%), day 4 (40.0 +/- 7.4%), and day 6 (38.1 +/- 2.0%). In addition, the total cell number of blastocysts was significantly decreased by heat shock on day 0 (107.5 +/- 6.6) and day 2 (112.8 +/- 5.7) compared with the control (143.2 +/- 9.4). To evaluate intracellular oxidative state by heat shock, embryos exposed to heat shock on days 0, 2, 4, and 6 were incubated with 2',7'-dichlorodihydrofluorescein diacetate (DCHFDA) and fluorescence of oxidized DCHFDA by reactive oxygen species (ROS) was detected under fluorescent microscope. The intensity of fluorescence was significantly increased when embryos were exposed to heat shock on days 0 and 2. However, heat shock on day 4 and day 6 did not increase the fluorescence intensity. These results indicate that (1) heat shock to earlier stage embryos causes a decrease in development to blastocysts and cell proliferation and (2) the decrease in development by heat shock could be involved in an increase of intracellular oxidative stress. Mol. Reprod. Dev. 67: 77-82, 2004.
Mol Reprod Dev 2004 Jan
PMID:Effects of heat shock on in vitro development and intracellular oxidative state of bovine preimplantation embryos. 1464 77

In our previous studies, we have partly elucidated the mechanism of radiation-induced apoptosis of human peripheral T cells. The exact site of the ROS (reactive oxygen species) formation induced by irradiation has been so far unknown. Therefore, in this study, we investigated the site of ROS formation by utilizing MitoCapture, H2DCFDA (succinimidyl ester of dichlorodihydrofluorescein diacetate), DAPI, and Lysosensor. Our results showed that ROS formation apparently originated in the mitochondria and/or lysosomes instead of in the nuclei of irradiated T cells. Moreover, lysosomal swelling and deformity, possibly revealing lysosomal membrane instability, were observed at 1 h after 5 Gy irradiation of T cells. At 4 h after irradiation of 5 Gy, increase of fluorescence around the lysosomes, possibly revealing lysosomal rupture, was seen. Based on the above results, we concluded the possible existence of a new apoptotic cascade involving early lysosomal membrane destabilization in radiation-induced apoptosis of human peripheral T cells. Therefore, possible involvement of lysosomal protease leakage caused by hydroxyl radical formation in lysosomes (possibly resulting in mitochondrial membrane dysfunction) is considered to play an important role in radiation-induced T cell apoptosis.
Int J Mol Med 2004 Jan
PMID:Reactive oxygen species-producing site in radiation-induced apoptosis of human peripheral T cells: involvement of lysosomal membrane destabilization. 1465 73

An efficient and reproducible protocol has been developed for the cryopreservation of cell suspension cultures of the potato (Solanum tuberosum L.) cv. Desiree. An evaluation was made of the effectiveness of different pre-culture and post-thaw treatments on cell growth, as measured by changes in biomass. Cell suspensions were cultured in UM medium supplemented with 0.25, 0.5, 0.625, 0.75 or 1.0 M sucrose prior to cryopreservation. Sucrose-treated cells were harvested from suspension and 0.75 ml packed cell volumes placed in 2 ml capacity polypropylene vials with 0.5 ml of chilled cryoprotectant (glycerol 46.0 g 1(-1), dimethylsulphoxide 39.0 g 1(-1), sucrose 342.0 g 1(-1) proline 5.0 g 1(-1); pH 5.8). Cells were frozen at -0.5 degrees C min(-1) from 0 to -35 degrees C, held at -35 degrees C for 35 min and stored, for 10 days, in liquid nitrogen (-196 degrees C). The most effective pre-treatment, in terms of subsequent post-thaw cell viability as assessed by fluorescein diacetate uptake or triphenyltetrazolium chloride reduction, was culture with 0.75 M sucrose. For this treatment, the mean absorbance (490 nm) following triphenyltetrazolium chloride reduction was 88% greater (p < 0.05) than control and 59% greater (p < 0.05) for thawed cells also cultured on supporting filter paper discs.
Cell Mol Biol Lett 2003
PMID:Culture treatments for enhancing post-thaw recovery of cryopreserved suspension cells of potato cv. Desiree. 1466 21

In our previous study, we examined the effect of exogenous hydrogen peroxide, which causes a potent oxidative stress and has been demonstrated to be a potent apoptosis-inducer in many kinds of cells. We found that the addition of 1 or 10 mM hydrogen peroxide induced reactive oxygen species (ROS) formation, oxidative DNA damage, dysfunction of the mitochondrial membrane potential, and early apoptotic changes in the human osteosarcoma cell line HS-Os-1. We therefore concluded that intracellular ROS formation was involved in the hydrogen peroxide-induced apoptosis of HS-Os-1 cells. In contrast to the osteosarcoma cell line HS-Os-1, human peripheral T cells are considered to be easily susceptible to oxidative stress, because these cells lack peroxidase activity. Therefore, in this study, we investigated the site of ROS formation by utilizing MitoCapture, H2DCFDA (succinimidyl ester of dichloro-dihydrofluorescein diacetate), DAPI (4',6-diamidino-2-phenylindole), and LysoSensor. Our results showed that ROS formation was apparently diffusely distributed in T cells oxidatively stressed with 0.1 mM hydrogen peroxide. Moreover, lysosomal swelling and deformity, possibly revealing lysosomal membrane destabilization, were observed in these cells. Based on the above results, there exists an apoptotic cascade involving early lysosomal membrane destabilization in the hydrogen peroxide-induced apoptosis of human peripheral T cells. Therefore, the possible involvement of lysosomal protease leakage caused by hydroxyl radical formation in lysosomes (possibly resulting in mitochondrial membrane dysfunction) is considered to play an important role in hydrogen peroxide-induced T cell apoptosis.
Int J Mol Med 2004 Mar
PMID:Reactive oxygen species-producing site in hydrogen peroxide-induced apoptosis of human peripheral T cells: involvement of lysosomal membrane destabilization. 1476 67

In our previous studies, we showed that the apoptotic resistance of the human osteosarcoma cell line HS-Os-1 against irradiation was easily converted to a state of apoptotic-susceptibility by the addition of a relatively low concentration of hydrogen peroxide to the culture medium just prior to irradiation. When we consider the combined use of radiotherapy and hydrogen peroxide in a clinical setting for patients with radioresistant neoplasms, we need to be careful of the possible augmentation of the radiation effect to normal tissues of patients who undergo radiation therapy for their tumor in the presence of a low concentration of hydrogen peroxide in their topical tumor tissue. Therefore, we examined the combined effect of irradiation and hydrogen peroxide compared to that of irradiation alone for human peripheral T cells which were considered to be representative of normal tissue susceptible to apoptosis induced by irradiation. In this study, we compared the morphological changes in human peripheral T cells between both groups by utilizing MitoCapture, H2DCFDA (succinimidyl ester of dichloro-dihydrofluorescein diacetate), DAPI (4',6-diamidino-2-phenylindole), and LysoSensor. Our results showed that ROS formation was apparently augmented in the mitochondria and/or lysosomes instead of in the nuclei of irradiated T cells in the presence of a low concentration of hydrogen peroxide compared to those treated with irradiation alone. Moreover, dysfunction of mitochondrial membrane potential was also more evidently shown in human peripheral T cells irradiated under existence of a low concentration of hydrogen peroxide compared to T cells treated with 5 Gy irradiation alone. Based on these results, we concluded the possible existence of an augmentation effect of irradiation by the existence of a low concentration of hydrogen peroxide for human peripheral T cells. Therefore, we should be alert for the combined effects of radiation therapy and hydrogen peroxide on normal tissues in possible clinical situations when this combination is used for treatment of patients having radioresistant neoplasms such as osteosarcoma, malignant melanoma, and glioblastoma multiforme.
Int J Mol Med 2004 May
PMID:Reactive oxygen species-producing site in radiation and hydrogen peroxide-induced apoptosis of human peripheral T cells: Involvement of lysosomal membrane destabilization. 1506 65

Recent data indicate that the oxidative stress plays an important role in the pathogenesis of diabetes and its complications such as retinopathy, nephropathy and accelerated atherosclerosis. In diabetic retinopathy, it was demonstrated a selective loss of pericytes accompanied by capillary basement membrane thickening, increased permeability and neovascularization. This study was designed to investigate the role of diabetic conditions such as high glucose, AGE-Lysine, and angiotensin II in the modulation of antioxidant enzymes activities, glutathione level and reactive oxygen species (ROS) production in pericytes. The activity of antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and total glutathione (GSH) was measured spectrophotometrically. The production of ROS was detected by spectrofluorimetry and fluorescence microscopy after loading the cells with 2'-7' dichlorofluoresceine diacetate; as positive control H2O2 was used. Intracellular calcium was determined using Fura 2 AM assay. The results showed that the cells cultured in high glucose alone, do not exhibit major changes in the antioxidant enzyme activities. The presence of AGE-Lys or Ang II induced the increase of SOD activity. Their combination decreased significantly GPx activity and GSH level. A three times increase in ROS production and a significant impairment of intracellular calcium homeostasis was detected in cells cultured in the presence of the three pro-diabetic agents used. In conclusion, our data indicate that diabetic conditions induce in pericytes: (i) an increase of ROS and SOD activity, (ii) a decrease in GPx activity and GSH level, (iii) a major perturbation of the intracellular calcium homeostasis. The data may explain the structural and functional abnormalities of pericytes characteristic for diabetic retinopathy.
J Cell Mol Med
PMID:Changes in oxidative balance in rat pericytes exposed to diabetic conditions. 1509 Feb 67


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