Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P30536 (PBS)
 9,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Alloxan participation in extracellular redox processes results in the formation of the reactive oxygen species (ROS) superoxide anions (O2-), hydroxyl radical (OH.) and hydrogen peroxide (H2O2), causing cell damage through a number of complex interactions probably involving several different cellular structures. These involve the plasma membrane, and we have recently presented evidence for lysosomal interference. The present study elucidates the early (within 15 min) events in a model system of macrophage-like cells (J-774) in culture. Addition of 2 mM alloxan and 1 mM cysteine to the medium surrounding the cells (phosphate-buffered saline, PBS, 37 degrees C, pH 7.4) resulted in rapid lysosomal membrane damage with disappearance of the proton gradient as visualized by acridine orange relocalization, as well as plasma membrane alterations leading to increased leakage of fluorescein after fluorescein diacetate staining. These events were later (greater than 30 min) followed by cellular degeneration in the form of blebbing. Mitochondrial damage (rhodamine 123 relocalization) was a late event. Cells pretreated with desferrioxamine (Des) and superoxide dismutase (SOD) or Des, SOD and catalase (CAT) to induce partial (H2O2 formation only) or almost full protection (no ROS formation) showed about the same reactions as when cells were exposed to alloxan and cysteine without scavengers (O2-, H2O2 and OH. formation) or with PBS only, respectively. The results are interpreted as indicating that the cytotoxicity is a consequence mainly of H2O2 involvement and probably of lysosomal influx of H2O2 with ensuing OH.formation within secondary lysosomes containing trace amounts of reactive iron. It is suggested that the resultant lysosomal membrane damage is followed by leakage of lysosomal hydrolases and ensuing cellular degeneration.
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PMID:Extracellular reduction of alloxan results in oxygen radical-mediated attack on plasma and lysosomal membranes. 158 Oct 40

Human skin fibroblasts deficient in peroxisome biogenesis were transformed by transfecting SV40 ori- DNA with the use of an electroporator, and the biochemical, immunocytochemical, and cytogenetic properties of the transformants were analyzed. Cells (1 x 10(6)) from a patient with Zellweger syndrome and one with neonatal adrenoleukodystrophy were suspended with 2 micrograms of SV40 ori- DNA in PBS; then a high-voltage pulse (2000 V, 30 microseconds) was generated two times. Several colonies expressing large T-antigen were picked up 4 weeks after transfection. Doubling time of the transformants was about half of that and the saturation density was 5 to 10 times greater than that of the parental cells. Biochemical abnormalities including defective lignoceric acid oxidation, dihydroxyacetone phosphate acyltransferase deficiency, and disturbed biosynthesis of peroxisomal beta-oxidation enzymes were preserved in the transformants. Peroxisomes were defective in all colonies, as determined by immunofluorescence staining using anti-catalase IgG. Cell fusion studies confirmed that the transformants belong to the same complementation groups as those of the parental cells. These transformed mutant cell lines are expected to be useful tools for investigating the pathogenesis of inherited diseases related to defects in peroxisome biogenesis.
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PMID:Transformation and characterization of mutant human fibroblasts defective in peroxisome assembly. 163 30

Cigarette smoke has been reported to contain free radicals and free radical generators in both the gas and particulate phases. Studies in our laboratory have shown that both cigarette smoke condensate (CSC) and smoke bubbled through phosphate buffered saline solution (smoke-PBS) increased sister chromatid exchanges (SCE) in Chinese hamster ovary cells in a dose-dependent manner. Since oxygen free radicals have been shown to cause SCEs and other chromosomal damage, we investigated the role of these radicals in the induction of SCEs by CSC and smoke-PBS. Addition of the antioxidant enzymes catalase and superoxide dismutase or the oxygen-radical scavenger ascorbic acid failed to reduce the SCE frequency in the presence of either CSC or smoke-PBS. Additional studies indicated that the quantity of hydrogen peroxide produced in CSC or smoke-PBS is too small to account for the observed SCE induction. It appears, therefore, that SCE induction by CSC or smoke-PBS does not involve the participation of oxygen free radicals.
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PMID:Role of oxygen free radicals in the induction of sister chromatid exchanges by cigarette smoke. 264 5

In this paper we report preliminary studies using alkaline elution to examine the incidence of DNA-strand breakage in human lung cells exposed to smoke/phosphate-buffered saline generated from cigarettes of different tar contents and filter status. The majority of the DNA breaks induced were abolished by catalase indicating a role for active oxygen species. The incidence of breaks did not correlate with the tar content of the cigarettes. The presence of a filter in the cigarette reduced the TPM concentration of the mainstream smoke but did not reduce the number of single-strand breaks occurring in DNA after exposure to smoke/PBS. This last parameter was however reduced if the filter was ventilated.
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PMID:Studies on the ability of smoke from different types of cigarettes to induce DNA single-strand breaks in cultured human cells. 277 Jul 60

In this laboratory, a silicone chamber model for peripheral nerve regeneration in adult rats has been developed and used to define basic principles of the regenerative events, such as the sequential stages being followed during 'spontaneous' regeneration in vivo and the role of neuronotrophic- and neurite-promoting factors as well as extracellular matrix molecules. Each of the defined stages seems amenable to experimental modulation. Previous attempts to enhance regeneration included increasing the volume of the nerve chambers along with the modification of fibrin matrix formation by prefilling with saline (PBS) or matrix precursors. We present here the results of a series of experiments on the effects of exogenous biochemical agents applied by multiple injections into these in vivo chambers. Out of a variety of agents screened, a mixture of laminin (L), testosterone (T), ganglioside GM 1 (G), and catalase (C) was shown to advance substantially the progress of regeneration in 16 day chambers, as compared to PBS-prefilled and PBS-injected controls. LTGC-treatment at day 0, 6, and 10 postimplantation caused an increasingly frequent occurrence of cellular elements in cross-sections obtained from the middle (S5) of the chambers (i.e. 5 mm from the proximal stump), which was 2-fold for vessels, 3-fold for Schwann cells, and 10-fold for axons. When only sections containing axons 3 mm from the proximal stump (S3) were compared in experimental and control groups, computerized area measurements also revealed an average 2-fold difference for the cross-sectional size of the whole regenerate, the endoneurium and the space occupied by blood vessels.
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PMID:Nerve regeneration chamber: evaluation of exogenous agents applied by multiple injections. 360 81

The exposure of quiescent Swiss 3T3 cells to mainstream cigarette smoke (CS) trapped in PBS solution (smoke-bubbled PBS) resulted in the dose-dependent expression of c-fos mRNA and protein. Kinetic investigations revealed that in contrast to mitogens, which strongly but transiently induce the c-fos promoter within minutes, c-fos transcripts in cells exposed to 0.03 puffs (approximately 1 cm3) of CS/ml of medium accumulated slowly but were still seen after 8 h; the maximum expression rates were between 2 and 6 h of exposure. This specific expression pattern appears to be the result of altered posttranscriptional as well as transcriptional regulation, since a strikingly increased stability of the c-fos message (t1/2, > or = 2 h versus < 20 min in serum-stimulated cells) in smoke-treated cells was observed in addition to slight transcriptional activation of the c-fos promoter. CS-dependent DNA damage can be excluded as the only source for this altered expression pattern, since inhibition of DNA strand break formation by either catalase or o-phenanthroline had no detectable effect on the CS-induced c-fos expression. The results described here, and other CS-dependent cellular and biochemical effects, are similar to those induced in vitro by okadaic acid, a specific inhibitor of cell growth-regulatory protein phosphatases 1/2A (PP-1/2A). Hence, the effects of smoke treatment on these key enzymes were compared to those of okadaic acid based on the ability of cell-free extracts to release radiolabeled phosphate from glycogen phosphorylase a, a substrate of PP-1/2A. Results from these experiments indicate that both treatments inhibited PP-1/2A in a concentration- and analogous time-dependent manner. The data presented suggest that PP-1/2A may, at least in vitro, be targeted by water-soluble active compounds present in cigarette smoke.
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PMID:Expression of c-fos in quiescent Swiss 3T3 cells exposed to aqueous cigarette smoke fractions. 772 61

Recent food listeriosis outbreaks confirm that more faithful isolation and identification methods for Listeria monocytogenes or other potentially pathogen microorganisms are required. Furthermore, the human and animal reservoir role in the ecology of this disease must be established. Listeria spp. in the vizcacha intestinal content was determined by two isolation procedures, starting from 10 g of homogenized samples in 40 ml of PBS. I)0.1 ml was stripped on phenylethanol agar, selective agar for Listeria and acryflavin ceftazidin agar, then incubated at 37 degrees C for 48 h, suspected colonies were identified by preliminary tests (Gram, hemolysis, catalase, esculin hydrolisis and motility at 22 degrees C) and confirmatory tests (indol, methyl red, Voges Proskauer, nitrate and carbohydrate fermentation) (Table 1). Antibiotic susceptibility, protein profile by PAGE and pathogenic power in mice were determined. II) The remaining homogenate was incubated at 4 degrees C in 100 ml of Donnelly and Baigent enrichment broth, weekly or monthly with subcultures until 30 days or 6-8 months, respectively. The subcultures were followed up as in I). A L. seeligeri strain, susceptible to antibiotics suggested for L. monocytogenes and exhibiting resistance to some second and third generation cephalosporins, was isolated (Table 2). The protein profile of both species was coincident, but L. seeligeri was not virulent for mice. The finding of L. seeligeri in an animal (4.0%) used as human feeding source is of interest due to its potential pathogen power.
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PMID:[Isolation of Listeria seeligery from cecum of vizcacha (Lagostomus maximus maximus)]. 776 3

Artemisinin and its derivatives are a promising new class of antimalarial agents containing an endoperoxide bridge. [14C]Artemisinin alkylated various proteins in vitro. Between 5 and 18% of added drug bound to hemoproteins such as catalase, cytochrome c, and hemoglobin. However, it did not react with heme-free globin. For catalase and hemoglobin, most of the drug reacted with the protein moiety rather than the heme. Artemisinin bound to human serum albumin (HSA) more efficiently at pH 8.6 than 7.4, more efficiently in Dulbecco's PBS than in Tris-HCl buffer, and better when HSA had been made fatty acid-free. Dihydroartemisinin also bound to HSA, whereas deoxyartemisinin, an inactive derivative, did not. There was no binding between DNA and artemisinin. These data provide insight into the mechanism of the reaction between artemisinin and proteins.
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PMID:Alkylation of proteins by artemisinin. Effects of heme, pH, and drug structure. 806 44

In the present study we have assayed antioxidant enzymatic activities of SOD, CAT, GSH-Px, GSH-Red, and G6PD in erythrocytes from two children with hemolytic-uremic syndrome (HUS) during the acute phase of the disease and after their recovery; in addition, we have tested the percentage of hemolysis after 24-h incubation in PBS containing glucose (1 g/1000 mL) or in the presence of their own plasma. Endogenous plasmatic MDA levels were also evaluated as lipid peroxidation marker. A significant decrease in SOD activity was found in erythrocytes from HUS patients, and the addition of their own plasma further decreased SOD activity. Elevated percentage of hemolysis was found in HUS patients when RBCs were incubated in their own plasma; this last effect was less evident in PBS + glucose.
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PMID:Impaired antioxidant defense mechanisms in two children with hemolytic-uremic syndrome. 821 May 65

A dose-dependent and transiently elevated expression of a cytoplasmic 32 kDa protein was observed in Swiss albino 3T3 fibroblasts exposed to mainstream cigarette smoke (CS) trapped in phosphate-buffered saline solutions (smoke-bubbled PBS). The protein was identified as heme oxygenase (HO) (heme, hydrogen donor:oxygen oxidoreductase, EC 1.14.99.3) by Western blotting using an anti-rodent HO-specific antibody. Kinetic investigations revealed that HO protein and its mRNA were detectable in smoke-bubbled PBS-treated cells between 1 and 24 h after exposure to 0.03 puffs (approximately 1 cm3) CS per ml medium. As a result of transcriptional activation, a nearly 50-fold increase in the amount of HO mRNA was determined after 8 h exposure compared to control levels. Since literature data indicate that there is a link between glutathione depletion and HO expression, the same was assumed for cells exposed to smoke-bubbled PBS, as a decrease of more than 60% in glutathione levels was observed after the exposure. This was further supported by the observation that no elevated amounts of HO mRNA appeared in smoke-bubbled PBS-treated cells when cysteine was exogenously added. However, although these effects may be attributable to the formation of hydroxyl radicals (which have been shown to induce HO and to deplete glutathione levels and which appear in aqueous smoke-containing solutions via the iron-catalysed Fenton reaction) neither catalase nor the iron cation chelating agent o-phenanthroline were able to suppress or even to reduce HO expression in smoke-bubbled PBS-treated cells. On the contrary, at comparable concentrations both compounds were found to be potent inhibitors of smoke-dependent DNA strand breaks. Hence, reactive species other than Fenton reaction-derived hydroxyl radicals are responsible for the effects observed in the present study.
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PMID:Heme oxygenase expression in Swiss 3T3 cells following exposure to aqueous cigarette smoke fractions. 829 50


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