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Morello N, Tonoli E, Logrand F, Fiorito V, Fagoonee S, Turco E, Silengo L, Vercelli A, Altruda F, Tolosano E. Haemopexin affects iron distribution and ferritin expression in mouse brain. J Cell Mol Med 2010; 13:4192-204. [PMID: 19120692 PMCID: PMC4496126 DOI: 10.1111/j.1582-4934.2008.00611.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Haemopexin (Hx) is an acute phase plasma glycoprotein, mainly produced by the liver and released into plasma where it binds heme with high affinity and delivers it to the liver. This system provides protection against free heme-mediated oxidative stress, limits access by pathogens to heme and contributes to iron homeostasis by recycling heme iron. Hx protein has been found in the sciatic nerve, skeletal muscle, retina, brain and cerebrospinal fluid (CSF). Recently, a comparative proteomic analysis has shown an increase of Hx in CSF from patients with Alzheimer’s disease, thus suggesting its involvement in heme detoxification in brain. Here, we report that Hx is synthesised in brain by the ventricular ependymal cells. To verify whether Hx is involved in heme scavenging in brain, and consequently, in the control of iron level, iron deposits and ferritin expression were analysed in cerebral regions known for iron accumulation. We show a twofold increase in the number of iron-loaded oligodendrocytes in the basal ganglia and thalamus of Hx-null mice compared to wild-type controls. Interestingly, there was no increase in H- and L-ferritin expression in these regions. This condition is common to several human neurological disorders such as Alzheimer’s disease and Parkinson’s disease in which iron loading is not associated with an adequate increase in ferritin expression. However, a strong reduction in the number of ferritin-positive cells was observed in the cerebral cortex of Hx-null animals. Consistent with increased iron deposits and inadequate ferritin expression, malondialdehyde level and Cu–Zn superoxide dismutase-1 expression were higher in the brain of Hx-null mice than in that of wild-type controls. These data demonstrate that Hx plays an important role in controlling iron distribution within brain, thus suggesting its involvement in iron-related neurodegenerative diseases.
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Affiliation(s)
- Noemi Morello
- Molecular Biotechnology Center, University of Torino, Torino, Italy
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202
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Lee SA, Kim EY, Jeon WK, Woo CH, Choe J, Han S, Kim BC. The inhibitory effect of raloxifene on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells is mediated through a ROS/p38 MAPK/CREB pathway to the up-regulation of heme oxygenase-1 independent of estrogen receptor. Biochimie 2010; 93:168-74. [PMID: 20888885 DOI: 10.1016/j.biochi.2010.09.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Accepted: 09/14/2010] [Indexed: 11/19/2022]
Abstract
In this study, we demonstrate that raloxifene, a selective estrogen receptor modulator, is a potent inducer of the anti-inflammatory enzyme heme oxygenase-1 (HO-1). In RAW264.7 macrophages, raloxifene induced HO-1 mRNA and protein expression. Pretreatment of ICI182780, an estrogen receptor (ER) antagonist or knock-down of endogenous ERα or ERβ gene by RNA interference failed to reverse raloxifene-mediated HO-1 induction, indicating an estrogen receptor-independent mechanism. Interestingly, the raloxifene-induced HO-1 expression was suppressed by reactive oxygen species (ROS) scavengers, including glutathione, TEMPO, Me(2)SO, 1,10-phenanthroline, or allopurinol. In addition, buthionine sulfoximine, an inhibitor of reduced glutathione synthesis, or Fe(2+)/Cu(2+) ions enhanced the positive effect of raloxifene on HO-1 expression. Consistent with these findings, raloxifene induced production of intracellular ROS and increased xanthine oxidase activity in vitro. Additional experiments revealed the involvement of mitogen-activated protein kinase (MAPK) kinase6 and p38 MAPK in the up-regulation of HO-1 by raloxifene and identified p38 MAPK as a downstream effector of ROS. Furthermore, the ROS-p38 MAPK cascade targeted the transcription factor cAMP-responsive element-binding protein (CREB). Finally, the functional significance of HO-1 induction was revealed by raloxifene-mediated inhibition of inducible nitric oxide synthase expression and nitric oxide production, a response reversed by the inhibition of HO-1 protein synthesis or blockade of p38 MAPK or xanthine oxidase activity. Therefore, identification of ROS-p38 MAPK-CREB-linked cascade as cellular relays in raloxifene-mediated HO-1 expression defines the signaling events that could participate in raloxifene-mediated anti-inflammatory response.
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Affiliation(s)
- Sin-Ae Lee
- Department of Biochemistry, College of Natural Sciences, Kangwon National University, 192-1 Hyoja-2-dong, Chuncheon 200-701, South Korea
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203
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Grimm S, Hoehn A, Davies KJ, Grune T. Protein oxidative modifications in the ageing brain: consequence for the onset of neurodegenerative disease. Free Radic Res 2010; 45:73-88. [PMID: 20815785 DOI: 10.3109/10715762.2010.512040] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The free radical theory of ageing proposes the accumulation of altered, less active and toxic molecules of DNA, RNA, proteins and lipids caused by reactive oxygen species and reactive nitrogen species. Neurodegenerative disorders are characterized by an abnormal accumulation of oxidatively damaged macromolecules inside cells and in the extracellular space. Proteins involved in the formation of aggregates are β-amyloid, tau, α-synuclein, parkin, prion proteins and proteins containing polyglutamine. These abnormal aggregated proteins influence normal cellular metabolism. Additionally, deposition of abnormal proteins induces oxidative stress and proteasomal as well as mitochondrial dysfunction that ultimately lead to neuronal cell death. This review focuses on the impact of oxidative and nitrative stress in the ageing brain and, consequently, on the generation of modified proteins, as these post-translational modifications are assumed to play an important role in the development of neurodegenerative diseases.
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Affiliation(s)
- Stefanie Grimm
- Institute of Nutrition, Friedrich Schiller University Jena, Dornburger Straße 24, 07743 Jena, Germany
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204
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Sohaebuddin SK, Thevenot PT, Baker D, Eaton JW, Tang L. Nanomaterial cytotoxicity is composition, size, and cell type dependent. Part Fibre Toxicol 2010; 7:22. [PMID: 20727197 PMCID: PMC2936333 DOI: 10.1186/1743-8977-7-22] [Citation(s) in RCA: 414] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Accepted: 08/21/2010] [Indexed: 11/17/2022] Open
Abstract
Background Despite intensive research efforts, reports of cellular responses to nanomaterials are often inconsistent and even contradictory. Additionally, relationships between the responding cell type and nanomaterial properties are not well understood. Using three model cell lines representing different physiological compartments and nanomaterials of different compositions and sizes, we have systematically investigated the influence of nanomaterial properties on the degrees and pathways of cytotoxicity. In this study, we selected nanomaterials of different compositions (TiO2 and SiO2 nanoparticles, and multi-wall carbon nanotubes [MWCNTs]) with differing size (MWCNTs of different diameters < 8 nm, 20-30 nm, > 50 nm; but same length 0.5-2 μm) to analyze the effects of composition and size on toxicity to 3T3 fibroblasts, RAW 264.7 macrophages, and telomerase-immortalized (hT) bronchiolar epithelial cells. Results Following characterization of nanomaterial properties in PBS and serum containing solutions, cells were exposed to nanomaterials of differing compositions and sizes, with cytotoxicity monitored through reduction in mitochondrial activity. In addition to cytotoxicity, the cellular response to nanomaterials was characterized by quantifying generation of reactive oxygen species, lysosomal membrane destabilization and mitochondrial permeability. The effect of these responses on cellular fate - apoptosis or necrosis - was then analyzed. Nanomaterial toxicity was variable based on exposed cell type and dependent on nanomaterial composition and size. In addition, nanomaterial exposure led to cell type dependent intracellular responses resulting in unique breakdown of cellular functions for each nanomaterial: cell combination. Conclusions Nanomaterials induce cell specific responses resulting in variable toxicity and subsequent cell fate based on the type of exposed cell. Our results indicate that the composition and size of nanomaterials as well as the target cell type are critical determinants of intracellular responses, degree of cytotoxicity and potential mechanisms of toxicity.
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Affiliation(s)
- Syed K Sohaebuddin
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA
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205
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Puttananjaiah MKH, Dhale MA, Gaonkar V, Keni S. Statins: 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitors demonstrate anti-atherosclerotic character due to their antioxidant capacity. Appl Biochem Biotechnol 2010; 163:215-22. [PMID: 20640529 DOI: 10.1007/s12010-010-9031-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Accepted: 07/01/2010] [Indexed: 12/24/2022]
Abstract
Atherosclerosis is a chronic inflammatory disease of multiple etiologies. It is associated with the accumulation of oxidized lipids in arterial lesions leading to coronary heart disease. 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (commonly known as statins) are widely used in cardiovascular disease prevention to lower the cholesterol. The antioxidant activity of HMG-CoA reductase inhibitors was studied by lipid peroxidation inhibition assay, DPPH, and hydroxyl radical scavenging-activity methods. The lovastatin (93%) and simvastatin (96%) showed significant action of lipid peroxidation inhibition compared to other HMG-CoA reductase inhibitors. The DPPH radical and hydroxyl radical scavenging activity of simvastatin was 38% and 33%, respectively. The oxidative modification of serum lipid due to reactive oxygen species causes atherosclerosis. This study revealed the importance of lovastatin and simvastatin to prevent oxidative stress-related cardiovascular diseases.
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Affiliation(s)
- Mohan-Kumari H Puttananjaiah
- Department of Food Microbiology, Central Food Technological Research Institute, Council of Scientific and Industrial Research, Mysore, India
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206
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Saini M, Tiwari S, Prasad J, Singh S, Kumar MSY, Bala M. Hippophae leaf extract concentration regulates antioxidant and prooxidant effects on DNA. J Diet Suppl 2010; 7:60-70. [PMID: 22435574 DOI: 10.3109/19390210903535027] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Extracts from Hippophae leaves constitute some commonly consumed beverages such as tea and wine. We had developed an extract of Hippophae leaves (SBL-1), which was rich in quercetin, had antimutagenic effects, radioprotective effects, and countered radiation-induced gene conversion in Saccharomyces cerevisiae. This study was designed to investigate the action of SBL-1 on guanine cytosine (GC)-rich nascent and mouse genomic DNA in vitro. The human and mouse liver DNA have about 43% GC content. Our results showed that at small concentration SBL-1 protected nascent as well as genomic DNA, while at large concentration SBL-1 damaged both types of DNA. The concentration of SBL-1 that protected DNA also demonstrated higher free radical scavenging activity. The reducing power of SBL-1 was greater than its free radical scavenging activity. The greater reducing power may have reduced the trace metals present in the SBL-1, leading to generation of hydroxyl radicals via Fenton reaction. The increased proportion of unscavenged hydroxyl radicals with increase in SBL-1 concentration may have been responsible for DNA damage or prooxidant effect of SBL-1 in vitro. This study suggests that the dietary supplements prepared from Hippophae should have low metal content.
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Affiliation(s)
- Manu Saini
- Division of Radiation Biology, Institute of Nuclear Medicine and Allied Sciences, New Delhi, India
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207
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Pikula J, Zukal J, Adam V, Bandouchova H, Beklova M, Hajkova P, Horakova J, Kizek R, Valentikova L. Heavy metals and metallothionein in vespertilionid bats foraging over aquatic habitats in the Czech Republic. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2010; 29:501-506. [PMID: 20821471 DOI: 10.1002/etc.80] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
There has been growing interest in the study and conservation of bats throughout the world. Declines in their absolute numbers in recent decades are due, in part, to the fact that insectivorous bats may bioaccumulate toxic pollutants. The purpose of the present study was to quantify heavy metal concentrations in kidney, liver, and pectoral muscle samples in relation to metallothionein (MT) levels. In total, 106 bats belonging to 11 European species (i.e., Myotis myotis, Myotis daubentonii, Myotis brandtii, Myotis nattereri, Myotis emarginatus, Myotis mystacinus, Pipistrellus pipistrellus, Pipistrellus nathusii, Pipistrellus pygmaeus, Nyctalus noctulla, Eptesicus serotinus) were used for the study. The highest MT levels were found in Pipistrellus pipistrellus. High MT levels were also found in juvenile bats and aquatic-insect-foraging species. Cadmium was found only in the liver and kidney of Myotis myotis, except for a solitary finding in Pipistrellus pipistrellus. Myotis myotis juveniles had significantly higher liver and kidney Zn concentrations than adults. Interestingly, the liver Pb concentration was approximately two times higher in females than in males of Myotis myotis. The same gender difference was found for kidney Zn concentration in Pipistrellus pipistrellus. The present study confirms exposure of vespertilionid bats to toxic heavy metals (Pb, Cd) in the Czech Republic and provides data on the essential element Zn and the metal-binding protein MT in bats foraging over aquatic, aquatic and terrestrial, and terrestrial habitats.
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Affiliation(s)
- Jiri Pikula
- University of Veterinary and Pharmaceutical Sciences, Palackeho 1-3, Brno, Czech Republic.
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208
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Oligonucleotides are potent antioxidants acting primarily through metal ion chelation. J Biol Inorg Chem 2010; 15:601-20. [PMID: 20155378 DOI: 10.1007/s00775-010-0628-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Accepted: 01/22/2010] [Indexed: 10/19/2022]
Abstract
We report on a rather unknown feature of oligonucleotides, namely, their potent antioxidant activity. Previously, we showed that nucleotides are potent antioxidants in Fe(II)/Cu(I/II)-H(2)O(2) systems. Here, we explored the potential of 2'-deoxyoligonucleotides as inhibitors of the Fe(II)/Cu(I/II)-induced *OH formation from H(2)O(2). The oligonucleotides [d(A)(5,7,20); d(T)(20); (2'-OMe-A)(5)] proved to be highly potent antioxidants with IC(50) values of 5-17 or 48-85 microM in inhibiting Fe(II)/Cu(I)- or Cu(II)-induced H(2)O(2) decomposition, respectively, thus representing a 40-215-fold increase in potency as compared with Trolox, a standard antioxidant. The antioxidant activity is only weakly dependent on the oligonucleotides' length or base identity. We analyzed by matrix-assisted laser desorption/ionization time of flight mass spectrometry and (1)H-NMR spectroscopy the composition of the d(A)(5) solution exposed to the aforementioned oxidative conditions for 4 min or 24 h. We concluded that the primary (rapid) inhibition mechanism by oligonucleotides is metal ion chelation and the secondary (slow) mechanism is radical scavenging. We characterized the Cu(I)-d(A)(5) and Cu(II)-d(A)(7) complexes by (1)H-NMR and (31)P-NMR or frozen-solution ESR spectroscopy, respectively. Cu(I) is probably coordinated to d(A)(5) via N1 and N7 of two adenine residues and possibly also via two phosphate/bridging water molecules. The ESR data suggest Cu(II) chelation through two nitrogen atoms of the adenine bases and two oxygen atoms (phosphates or water molecules). We conclude that oligonucleotides at micromolar concentrations prevent Fe(II)/Cu(I/II)-induced oxidative damage, primarily through metal ion chelation. Furthermore, we propose the use of a short, metabolically stable oligonucleotide, (2'-OMe-A)(5), as a highly potent and relatively long lived (t(1/2) approximately 20 h) antioxidant.
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209
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Shokouhimehr M, Soehnlen ES, Hao J, Griswold M, Flask C, Fan X, Basilion JP, Basu S, Huang SD. Dual purpose Prussian blue nanoparticles for cellular imaging and drug delivery: a new generation of T1-weighted MRI contrast and small molecule delivery agents. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/b923184f] [Citation(s) in RCA: 186] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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210
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The effect of oxidative stress on nucleotide-excision repair in colon tissue of newborn piglets. Mutat Res 2009; 695:75-80. [PMID: 20015477 DOI: 10.1016/j.mrgentox.2009.12.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2009] [Revised: 08/08/2009] [Accepted: 08/28/2009] [Indexed: 11/22/2022]
Abstract
Nucleotide-excision repair (NER) is important for the maintenance of genomic integrity and to prevent the onset of carcinogenesis. Oxidative stress was previously found to inhibit NER in vitro, and dietary antioxidants could thus protect DNA not only by reducing levels of oxidative DNA damage, but also by protecting NER against oxidative stress-induced inhibition. To obtain further insight in the relation between oxidative stress and NER activity in vivo, oxidative stress was induced in newborn piglets by means of intra-muscular injection of iron (200mg) at day 3 after birth. Indeed, injection of iron significantly increased several markers of oxidative stress, such as 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) levels in colon DNA and urinary excretion of 8-oxo-7,8-dihydroguanine (8-oxoGua). In parallel, the influence of maternal supplementation with an antioxidant-enriched diet was investigated in their offspring. Supplementation resulted in reduced iron concentrations in the colon (P=0.004) at day 7 and a 40% reduction of 8-oxodG in colon DNA (P=0.044) at day 14 after birth. NER capacity in animals that did not receive antioxidants was significantly reduced to 32% at day 7 compared with the initial NER capacity on day 1 after birth. This reduction in NER capacity was less pronounced in antioxidant-supplemented piglets (69%). Overall, these data indicate that NER can be reduced by oxidative stress in vivo, which can be compensated for by antioxidant supplementation.
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211
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Huang CH, Lee IL, Yeh IJ, Liao JH, Ni CL, Wu SH, Chiou SH. Upregulation of a non-heme iron-containing ferritin with dual ferroxidase and DNA-binding activities in Helicobacter pylori under acid stress. J Biochem 2009; 147:535-43. [PMID: 19959503 DOI: 10.1093/jb/mvp200] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Helicobacter pylori is a spiral Gram-negative microaerophilic bacterium. It is unique and distinctive among various bacterial pathogens for its ability to persist in the extreme acidic environment of human stomachs. To address and identify changes in the proteome of H. pylori in response to low pH, we have used a proteomic approach to study the protein expression of H. pylori under neutral (pH 7) and acidic (pH 5) conditions. Global protein-expression profiles of H. pylori under acid stress were analysed by two-dimensional polyacrylamide gel electrophoresis (2-DE) followed by liquid chromatography (LC)-nanoESI-mass spectrometry (MS)/MS and bioinformatics database analysis. Among the proteins differentially expressed under acidic condition, a non-heme iron-containing ferritin of H. pylori (HP-ferritin) was found to be consistently upregulated at pH 5 as compared to pH 7. It was also found that HP-ferritin can switch from an iron-storage protein with ferroxidase activity to a DNA-binding/protection function under in vitro conditions upon exposure to acidic environment. Prokaryotic ferritins, such as non-heme iron-binding HP-ferritin with dual functionality reported herein, may play a significant urease-independent role in the acid adaptation of H. pylori under physiological conditions in vivo.
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Affiliation(s)
- Chun-Hao Huang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
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212
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Pisanelli B, Benedetti M, Fattorini D, Regoli F. Seasonal and inter-annual variability of DNA integrity in mussels Mytilus galloprovincialis: a possible role for natural fluctuations of trace metal concentrations and oxidative biomarkers. CHEMOSPHERE 2009; 77:1551-1557. [PMID: 19863990 DOI: 10.1016/j.chemosphere.2009.09.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Revised: 09/02/2009] [Accepted: 09/21/2009] [Indexed: 05/28/2023]
Abstract
The DNA strand fragmentation as analyzed by the Comet assay is a common biomarker widely used to assess the genotoxic potential of chemical pollutants in marine organisms. However, basal levels of DNA strand breaks can be influenced also by factors unrelated to chemical exposure, and a better knowledge on the natural variability of such response would thus be important to discriminate the effects of anthropogenic activities. In this respect, the aim of the present work was to characterize the fluctuations of DNA strand breaks in mussels, Mytilus galloprovincialis, seasonally sampled over a 3 year period from a reference site along the Adriatic coast. Parameters reflecting DNA integrity exhibited significant seasonal changes in mussels haemocytes, with considerable differences between various sampling years. Comparing such results with those previously obtained on the natural fluctuations of trace metal concentrations and oxidative stress biomarkers in mussels tissues, significant correlations were obtained between DNA strand breaks with levels of Ba, Cd, Cu, Hg, Ni, Se, activity of catalase and content of malondialdehyde. Although mechanisms remain to be demonstrated, the overall results of this work suggest the potential role of natural prooxidant factors in affecting the baseline levels of DNA integrity in mussels, and confirm that natural variability of such responses should be carefully considered when monitoring the impact of genotoxins in marine ecosystems.
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Affiliation(s)
- Barbara Pisanelli
- Dipartimento di Biochimica, Biologia e Genetica, Università Politecnica delle Marche, Ancona, Italy
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213
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Kaspar JW, Niture SK, Jaiswal AK. Nrf2:INrf2 (Keap1) signaling in oxidative stress. Free Radic Biol Med 2009; 47:1304-9. [PMID: 19666107 PMCID: PMC2763938 DOI: 10.1016/j.freeradbiomed.2009.07.035] [Citation(s) in RCA: 1210] [Impact Index Per Article: 80.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2009] [Revised: 07/30/2009] [Accepted: 07/31/2009] [Indexed: 12/14/2022]
Abstract
Nrf2:INrf2 (Keap1) are cellular sensors of chemical- and radiation-induced oxidative and electrophilic stress. Nrf2 is a nuclear transcription factor that controls the expression and coordinated induction of a battery of defensive genes encoding detoxifying enzymes and antioxidant proteins. This is a mechanism of critical importance for cellular protection and cell survival. Nrf2 is retained in the cytoplasm by an inhibitor, INrf2 which functions as an adapter for Cul3/Rbx1-mediated degradation of Nrf2. In response to oxidative/electrophilic stress, Nrf2 is switched on and then off by distinct early and delayed mechanisms. Oxidative/electrophilic modification of INrf2 cysteine 151 and/or protein kinase C phosphorylation of Nrf2 serine 40 results in the escape or release of Nrf2 from INrf2. Nrf2 is stabilized and translocates to the nucleus, forms heterodimers with unknown proteins, and binds the antioxidant response element, which leads to coordinated activation of gene expression. It takes less than 15 min from the time of exposure to switch on nuclear import of Nrf2. This is followed by activation of a delayed mechanism that controls the switching off of Nrf2 activation of gene expression. GSK3beta phosphorylates Fyn at an unknown threonine residue(s), leading to the nuclear localization of Fyn. Fyn phosphorylates Nrf2 tyrosine 568, resulting in the nuclear export of Nrf2, binding with INrf2, and degradation of Nrf2. The switching on and off of Nrf2 protects cells against free radical damage, prevents apoptosis, and promotes cell survival.
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214
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Boen TR, Lima Pallone JA. Folic Acid, Iron, and Zinc Contents in Chosen Food Products Prepared with Fortified Flours. Cereal Chem 2009. [DOI: 10.1094/cchem-86-6-0695] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Thaís Rezende Boen
- Pontifícia Universidade Católica de Campinas, Faculty of Chemistry, Rod. D. Pedro I, Km 136, 13086-900, Campinas, SP, Brazil
| | - Juliana A. Lima Pallone
- State University of Campinas, Faculty of Food Engineering, Food Science Department, 13083-970, Campinas, SP, Brazil
- Corresponding author. E-mail:
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215
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Kariya S, Sawada K, Kobayashi T, Karashima T, Shuin T, Nishioka A, Ogawa Y. Combination Treatment of Hydrogen Peroxide and X-Rays Induces Apoptosis in Human Prostate Cancer PC-3 Cells. Int J Radiat Oncol Biol Phys 2009; 75:449-54. [DOI: 10.1016/j.ijrobp.2009.04.092] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Revised: 04/16/2009] [Accepted: 04/23/2009] [Indexed: 11/28/2022]
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216
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Soeiro BT, Boen TR, Wagner R, Lima-Pallone JA. Physico-chemical quality and homogeneity of folic acid and iron in enriched flour using principal component analysis. Int J Food Sci Nutr 2009; 60 Suppl 7:167-79. [DOI: 10.1080/09637480902769567] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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217
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Abstract
Nrf2:INrf2 (Keap1) are cellular sensors of chemical- and radiation-induced oxidative and electrophilic stress. Nrf2 is a nuclear transcription factor that controls the expression and coordinated induction of a battery of defensive genes encoding detoxifying enzymes and antioxidant proteins. This is a mechanism of critical importance for cellular protection and cell survival. Nrf2 is retained in the cytoplasm by an inhibitor, INrf2 which functions as an adapter for Cul3/Rbx1-mediated degradation of Nrf2. In response to oxidative/electrophilic stress, Nrf2 is switched on and then off by distinct early and delayed mechanisms. Oxidative/electrophilic modification of INrf2 cysteine 151 and/or protein kinase C phosphorylation of Nrf2 serine 40 results in the escape or release of Nrf2 from INrf2. Nrf2 is stabilized and translocates to the nucleus, forms heterodimers with unknown proteins, and binds the antioxidant response element, which leads to coordinated activation of gene expression. It takes less than 15 min from the time of exposure to switch on nuclear import of Nrf2. This is followed by activation of a delayed mechanism that controls the switching off of Nrf2 activation of gene expression. GSK3beta phosphorylates Fyn at an unknown threonine residue(s), leading to the nuclear localization of Fyn. Fyn phosphorylates Nrf2 tyrosine 568, resulting in the nuclear export of Nrf2, binding with INrf2, and degradation of Nrf2. The switching on and off of Nrf2 protects cells against free radical damage, prevents apoptosis, and promotes cell survival.
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218
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Lee DH, Lim JS, Yang JH, Ha MH, Jacobs DR. Serum gamma-glutamyltransferase within its normal range predicts a chronic elevation of alanine aminotransferase: A four year follow-up study. Free Radic Res 2009; 39:589-93. [PMID: 16036336 DOI: 10.1080/10715760400016154] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Previous epidemiological and experimental studies support the concept that serum gamma-glutamyltransferase (GGT) activity within its normal range is related to oxidative stress. Since oxidative stress plays a crucial role in the pathogenesis of various liver diseases, serum GGT may predict development of liver damage. METHODS A total of 6,523 healthy male workers with normal alanine aminotransferase (ALT, <35 U/l) in a steel manufacturing company were followed for four years. Liver damage was defined as a chronic elevation of serum ALT (both 2001 and 2002). RESULTS After adjusting for age, body mass index, alcohol consumption, cigarette smoking, exercise, and baseline value of ALT, in comparison with the group whose GGT level was <10 U/l, the adjusted relative risks for elevated ALT level among those with GGT levels 10-19, 20-29, 30-39, and over 40 U/l was 1.0, 2.5, 4.7, 7.4, and 12.0, respectively (P for trend <0.01). More importantly, this association was similarly observed even among non-drinkers; the corresponding relative risks were 1.0, 1.8, 3.8, 5.6, and 6.2 (P for trend <0.01). However baseline ALT did not predict abnormal GGT level four years later. CONCLUSION Serum GGT levels within normal range predict incidence of chronic elevation of ALT. Oxidative stress might explain this relationship.
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Affiliation(s)
- Duk-Hee Lee
- Division of Preventive Medicine and Health Promotion Research Center, School of Medicine, Kyungpook National University, 101 Dongin-dong, Jung-gu, Daegu, 700-422, South Korea.
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219
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Wang G, Conover RC, Olczak AA, Alamuri P, Johnson MK, Maier RJ. Oxidative stress defense mechanisms to counter iron-promoted DNA damage inHelicobacter pylori. Free Radic Res 2009; 39:1183-91. [PMID: 16298744 DOI: 10.1080/10715760500194018] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Iron, a key element in Fenton chemistry, causes oxygen-related toxicity to cells of most living organisms. Helicobacter pylori is a microaerophilic bacterium that infects human gastric mucosa and causes a series of gastric diseases. Exposure of H. pylori cells to air for 2 h elevated the level of free iron by about 4-fold as measured by electron paramagnetic resonance spectroscopy. H. pylori cells accumulated more free iron as they approached stationary phase growth, and they concomitantly suffered more DNA damage as indicated by DNA fragmentation analysis. Relationships between the intracellular free iron level, specific oxidative stress enzymes, and DNA damage were identified, and new roles for three oxidative stress-combating enzymes in H. pylori are proposed. Mutant cells defective in either catalase (KatA), in superoxide dismutase (SodB) or in alkyl hydroperoxide reductase (AhpC) were more sensitive to oxidative stress conditions; and they accumulated more free (toxic) iron; and they suffered more DNA fragmentation compared to wild type cells. A significant proportion of cells of sodB, ahpC, or katA mutant strains developed into the stress-induced coccoid form or lysed; they also contained significantly higher amounts of 8-oxo-guanine associated with their DNA, compared to wild type cells.
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Affiliation(s)
- Ge Wang
- Department of Microbiology, University of Georgia, Athens, 30602, USA
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220
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Doulias PT, Nousis L, Zhu BZ, Frei B, Galaris D. Protection by tropolones against H2O2-induced DNA damage and apoptosis in cultured Jurkat cells. Free Radic Res 2009; 39:125-35. [PMID: 15763960 DOI: 10.1080/10715760400017244] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Tropolones, the naturally occurring compounds responsible for the durability of heartwood of several cupressaceous trees, have been shown to possess both metal chelating and antioxidant properties. However, little is known about the ability of tropolone and its derivatives to protect cultured cells from oxidative stress-mediated damage. In this study, the effect of tropolones on hydrogen peroxide-induced DNA damage and apoptosis was investigated in cultured Jurkat cells. Tropolone, added to the cells 15 min before the addition of glucose oxidase, provided a dose dependent protection against hydrogen peroxide induced DNA damage. The IC50 value observed was about 15 microM for tropolone. Similar dose dependent protection was also observed with three other tropolone derivatives such as trimethylcolchicinic acid, purpurogallin and beta-thujaplicin (the IC50 values were 34, 70 and 74 microM, respectively), but not with colchicine and tetramethyl purpurogallin ester. Hydrogen peroxide-induced apoptosis was also inhibited by tropolone. However, in the absence of exogenous H2O2 but in the presence of non-toxic concentrations of exogenous iron (100 microM Fe3+), tropolone dramatically increased the formation of single strand breaks at molar ratios of tropolone to iron lower than 3 to 1, while, when the ratio increased over 3, no toxicity was observed. In conclusion, the results presented in this study indicate that the protection offered by tropolone against hydrogen peroxide-induced DNA damage and apoptosis was due to formation of a redox-inactive iron complex, while its enhancement of iron-mediated DNA damage at ratios of [tropolone]/[Fe3+] lower than 3, was due to formation of a lipophilic iron complex which facilitates iron transport through cell membrane in a redox-active form.
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Affiliation(s)
- Paschalis-Thomas Doulias
- Laboratory of Biological Chemistry, University of Ioannina Medical School, 451 10, Ioannina, Greece
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221
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Antioxidant activity of sulfur and selenium: a review of reactive oxygen species scavenging, glutathione peroxidase, and metal-binding antioxidant mechanisms. Cell Biochem Biophys 2009; 55:1-23. [PMID: 19548119 DOI: 10.1007/s12013-009-9054-7] [Citation(s) in RCA: 280] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2009] [Accepted: 06/03/2009] [Indexed: 02/07/2023]
Abstract
It is well known that oxidation caused by reactive oxygen species (ROS) is a major cause of cellular damage and death and has been implicated in cancer, neurodegenerative, and cardiovascular diseases. Small-molecule antioxidants containing sulfur and selenium can ameliorate oxidative damage, and cells employ multiple antioxidant mechanisms to prevent this cellular damage. However, current research has focused mainly on clinical, epidemiological, and in vivo studies with little emphasis on the antioxidant mechanisms responsible for observed sulfur and selenium antioxidant activities. In addition, the antioxidant properties of sulfur compounds are commonly compared to selenium antioxidant properties; however, sulfur and selenium antioxidant activities can be quite distinct, with each utilizing different antioxidant mechanisms to prevent oxidative cellular damage. In the present review, we discuss the antioxidant activities of sulfur and selenium compounds, focusing on several antioxidant mechanisms, including ROS scavenging, glutathione peroxidase, and metal-binding antioxidant mechanisms. Findings of several recent clinical, epidemiological, and in vivo studies highlight the need for future studies that specifically focus on the chemical mechanisms of sulfur and selenium antioxidant behavior.
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222
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Elemental analysis of brahmi (Bacopa monnieri) extracts by neutron activation and its bioassay for antioxidant, radio protective and anti-lipid peroxidation activity. J Radioanal Nucl Chem 2009. [DOI: 10.1007/s10967-009-0081-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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223
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Niture SK, Kaspar JW, Shen J, Jaiswal AK. Nrf2 signaling and cell survival. Toxicol Appl Pharmacol 2009; 244:37-42. [PMID: 19538984 DOI: 10.1016/j.taap.2009.06.009] [Citation(s) in RCA: 299] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Revised: 05/28/2009] [Accepted: 06/05/2009] [Indexed: 12/30/2022]
Abstract
Nrf2:INrf2 acts as a sensor for oxidative/electrophilic stress. INrf2 serves as an adaptor to link Nrf2 to the ubiquitin ligase Cul3-Rbx1 complex that ubiquitinate and degrade Nrf2. Under basal conditions, cytosolic INrf2/Cul3-Rbx1 is constantly degrading Nrf2. When a cell encounters stress Nrf2 dissociates from the INrf2 and translocates into the nucleus. Oxidative/electrophilic stress induced modification of INrf2Cysteine151 and/or protein kinase C (PKC)-mediated phosphorylation of Nrf2Serine40 controls Nrf2 release from INrf2 followed by stabilization and nuclear translocation of Nrf2. Nrf2 binds to the antioxidant response element (ARE) and activates a myriad of genes that protect cells against oxidative/electrophilic stress and neoplasia. A delayed response of oxidative/electrophilic stress activates GSK-3beta that phosphorylates Fyn at unknown threonine residue(s). Phosphorylated Fyn translocates to the nucleus and phosphorylates Nrf2Tyrosine568 that leads to nuclear export and degradation of Nrf2. Prothymosin-alpha mediated nuclear translocation of INrf2 also degrades nuclear Nrf2. The degradation of Nrf2 both in cytosol and nuclear compartments rapidly brings down its levels to normal resulting in suppression of Nrf2 downstream gene expression. An auto-regulatory loop between Nrf2 and INrf2 controls their cellular abundance. Nrf2 regulates INrf2 by controlling its transcription, and INrf2 controls Nrf2 by degrading it. In conclusion, switching on and off of Nrf2 combined with promoting an auto-regulatory loop between them regulates activation/deactivation of defensive genes leading to protection of cells against adverse effects of oxidative and electrophilic stress and promote cell survival.
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Affiliation(s)
- Suryakant K Niture
- Department of Pharmacology, University of Maryland School of Medicine, 655 West Baltimore Street, Baltimore, MD 21201, USA
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224
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Tan MGK, Kumarasinghe MP, Wang SM, Ooi LLPJ, Aw SE, Hui KM. Modulation of Iron-Regulatory Genes in Human Hepatocellular Carcinoma and Its Physiological Consequences. Exp Biol Med (Maywood) 2009; 234:693-702. [PMID: 19307463 DOI: 10.3181/0807-rm-227] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Hepatocellular carcinoma (HCC) commonly develops in patients with underlying chronic liver disease. Additionally, the tumorous lesions of HCC patients are consistently characterized by the lack of iron accumulation even when arising in iron-loaded liver. However, the molecular mechanism leading to this observed phenomenon is currently poorly understood. In this study, all tumorous tissues from 24 HCC patients with chronic HBV infection were stained negative for iron when histologically assessed by Perls’ Prussian blue stain, whereas excess iron deposits were present in 17 of the 24 adjacent non-tumorous liver tissues. To elucidate the concerted regulation of iron homeostasis in these patients, we studied the gene expression profiling of 42 relevant iron-regulatory genes in the tumorous and adjacent non-tumorous liver tissues of these HCC patients along with 10 normal liver controls. Expression for most of the iron-regulatory genes, including hepcidin, transferrin receptor 2 (TfR2), transferrin (Tf), ceruloplasmin (Cp) and iron regulatory protein 1 (IRP1), were significantly down-regulated in the tumorous tissues of these patients compared to the adjacent non-tumorous liver tissues and normal liver controls. On the other hand, expression of hepcidin, TfR2, ferroportin 1 and DMT1 were significantly up-regulated in iron-loaded non-cirrhotic non-tumorous liver tissues as compared with normal liver controls. Hence, the reduction of hepcidin expression within the iron-depleted tumorous lesions likely reflects the physiological consequence of the obligate demand for iron in the rapidly growing neoplastic cells, whereas the up-regulation of hepcidin expression in the iron-loaded adjacent non-tumorous liver tissues is likely a physiological response.
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225
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Abstract
In my career I have moved from chemistry to biochemistry to plant science to clinical chemistry and back again (in a partial way) to plants. This review presents a brief history of my research achievements (ascorbate-glutathione cycle, role of iron in oxidative damage and human disease, biomarkers of free radical damage, and studies on atherosclerosis and neurodegeneration) and how they relate to my research activities today. The field of free radicals/other reactive species/antioxidants underpins all of modern Biology. These agents helped to drive human evolution and the basic principles of the field are repeatedly found to be relevant in other research areas. It was an exciting field when I started some 40 years ago, and it still is today, but some major challenges must be faced.
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Affiliation(s)
- Barry Halliwell
- Department of Biochemistry, National University of Singapore, Singapore.
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226
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Sang N, Hou L, Yun Y, Li G. SO(2) inhalation induces protein oxidation, DNA-protein crosslinks and apoptosis in rat hippocampus. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2009; 72:879-884. [PMID: 18722661 DOI: 10.1016/j.ecoenv.2008.07.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2007] [Revised: 07/07/2008] [Accepted: 07/12/2008] [Indexed: 05/26/2023]
Abstract
Previous studies provide evidence for the possible neurotoxicity of SO(2), but little information is available about its mechanisms. In the present study, SO(2) inhalation-induced effects on the protein oxidation, DNA-protein crosslinks and apoptosis in rat hippocampus were studied, by exposing Wistar rats to SO(2) at 14, 28 and 56mg/m(3). The results indicate that the protein carbonyl content, an indicator of protein oxidation, and DNA-protein crosslink coefficient were significantly augmented with concentration-dependent properties. In addition, SO(2) inhalation at all concentrations tested caused the increases of caspase-3 activity and number of TUNEL positive staining neuron and the statistical difference was observed after 28 and 56mg/m(3) exposure, suggesting the occurrence of apoptosis. The results imply that attacking protein, nucleic acids and lipids by free radicals, generated via SO(2) derivatives in vivo, is one of the main mechanisms for SO(2)-induced injuries in central neuronal system.
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Affiliation(s)
- Nan Sang
- Center of Environmental Science and Engineering, College of Environment and Resource, Shanxi University, Taiyuan, Shanxi 030006, PR China
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227
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Sorrentino P, D'Angelo S, Ferbo U, Micheli P, Bracigliano A, Vecchione R. Liver iron excess in patients with hepatocellular carcinoma developed on non-alcoholic steato-hepatitis. J Hepatol 2009; 50:351-7. [PMID: 19070395 DOI: 10.1016/j.jhep.2008.09.011] [Citation(s) in RCA: 143] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Revised: 07/04/2008] [Accepted: 09/11/2008] [Indexed: 12/15/2022]
Abstract
BACKGROUND/AIMS Liver iron deposits are frequent in patients with non-alcoholic steato-hepatitis (NAFLD), but their role is not well defined. To investigate the effect of liver iron excess on the prevalence of hepatocellular carcinoma (HCC) in patients with NASH-related cirrhosis. METHODS Hepatic iron was measured retrospectively with a semiquantitative method in liver biopsies of 153 patients with NASH-related cirrhosis: 51 with HCC and 102 controls without HCC, matched for age, sex and stage of liver disease. The corrected total iron score (0-60) was the sum of three scores: the hepatocytic iron score (0-36), sinusoidal iron score (0-12), and portal iron score (0-12), multiplied by 3/3, 2/3, or 1/3 depending on the localisation of the iron in the nodules. RESULTS Conditional logistic regression analysis showed that iron deposits (corrected total iron score>0) were more frequent in HCC patients than in controls. The median corrected total iron score was significantly higher in HCC patients than in controls. The liver iron overload was sinusoidal. CONCLUSIONS Iron deposition in the liver was more frequent in patients with NASH-related cirrhosis with HCC than in HCC-free controls. Liver iron overload may be associated with development of HCC in patients with NASH-related cirrhosis.
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Affiliation(s)
- Paolo Sorrentino
- Liver Unit, Clinical and Experimental Hepatology, Department of Internal Medicine, S.G. Moscati Hospital, Avellino, Italy.
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228
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Beazley KE, Nurminskaya M, Talbot CJ, Linsenmayer TF. Corneal epithelial nuclear ferritin: developmental regulation of ferritin and its nuclear transporter ferritoid. Dev Dyn 2009; 237:2529-41. [PMID: 18729209 DOI: 10.1002/dvdy.21691] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The corneal epithelium is exposed to reactive oxygen species that are potentially deleterious to nuclear DNA. However, our previous studies show that corneal epithelial cells have a novel, developmentally regulated mechanism for protection from such damage that involves having the iron-sequestering molecule, ferritin, in the nucleus. Nuclear localization of ferritin is achieved through the action of a tissue-specific nuclear transporter, ferritoid, which is itself a ferritin family member. Here, we show that during development ferritoid appears before ferritin. At this time, ferritoid is cytoplasmic, suggesting that its nuclear transport function requires an interaction with ferritin. To examine the developmental regulation of these two interacting components, cultured corneas were treated with the iron chelator deferoxamine. The results show that, while iron-mediated translational regulation is involved in the synthesis of both molecules, ferritoid is also transcriptionally regulated, demonstrating that these family members--whose functions depend upon one another--are regulated differently.
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Affiliation(s)
- Kelly E Beazley
- Department of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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229
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Pialoux V, Mounier R, Brown AD, Steinback CD, Rawling JM, Poulin MJ. Relationship between oxidative stress and HIF-1 alpha mRNA during sustained hypoxia in humans. Free Radic Biol Med 2009; 46:321-6. [PMID: 19028566 DOI: 10.1016/j.freeradbiomed.2008.10.047] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2008] [Revised: 10/23/2008] [Accepted: 10/25/2008] [Indexed: 11/16/2022]
Abstract
The aim of this study was to investigate the relations among reactive oxygen species (ROS), hypoxia inducible factor (HIF-1 alpha) gene expression, HIF-1 alpha target gene erythropoietin (EPO), and vascular endothelium growth factor (VEGF) in humans. Five healthy men (32+/-7 years, mean+/-SD) were exposed to 12 h of sustained poikilocapnic hypoxia (P(ET)O(2)=60 mmHg). DNA oxidation (8-hydroxy-2'-deoxyguanosine, 8-OHdG), advanced oxidation protein products (AOPP), EPO, and VEGF were measured in plasma and HIF-1 alpha mRNA was assessed in leukocytes before and after 1, 2, 4, 6, 8, 10, and 12 h of exposure to hypoxia. HIF-1 alpha mRNA amount increased during the first two hours of hypoxic exposure and then returned to baseline levels. The findings reveal an up-regulation of HIF-1 alpha (+68%), VEGF (+46%), and EPO (+74%). AOPP increased continuously from 4 h (+69%) to 12 h (+216%) of hypoxic exposure while 8-OHdG increased after 6 h (+78%) and remained elevated until 12 h. During the "acute" increase phase of HIF-1 alpha (between 0 and 2 h), 8-OHdG was positively correlated with HIF-1 alpha (r=0.55). These findings suggest that hypoxia induces oxidative stress via an overgeneration of reactive oxygen species (ROS). Finally, this study in humans corroborates the previous in vitro findings demonstrating that ROS is involved in HIF-1 alpha transcription.
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Affiliation(s)
- Vincent Pialoux
- Department of Physiology & Biophysics, University of Calgary, Calgary, AB, Canada
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230
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Kell DB. Iron behaving badly: inappropriate iron chelation as a major contributor to the aetiology of vascular and other progressive inflammatory and degenerative diseases. BMC Med Genomics 2009; 2:2. [PMID: 19133145 PMCID: PMC2672098 DOI: 10.1186/1755-8794-2-2] [Citation(s) in RCA: 364] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Accepted: 01/08/2009] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular 'reactive oxygen species' (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. REVIEW We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation).The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible.This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, since in some circumstances (especially the presence of poorly liganded iron) molecules that are nominally antioxidants can actually act as pro-oxidants. The reduction of redox stress thus requires suitable levels of both antioxidants and effective iron chelators. Some polyphenolic antioxidants may serve both roles.Understanding the exact speciation and liganding of iron in all its states is thus crucial to separating its various pro- and anti-inflammatory activities. Redox stress, innate immunity and pro- (and some anti-)inflammatory cytokines are linked in particular via signalling pathways involving NF-kappaB and p38, with the oxidative roles of iron here seemingly involved upstream of the IkappaB kinase (IKK) reaction. In a number of cases it is possible to identify mechanisms by which ROSs and poorly liganded iron act synergistically and autocatalytically, leading to 'runaway' reactions that are hard to control unless one tackles multiple sites of action simultaneously. Some molecules such as statins and erythropoietin, not traditionally associated with anti-inflammatory activity, do indeed have 'pleiotropic' anti-inflammatory effects that may be of benefit here. CONCLUSION Overall we argue, by synthesising a widely dispersed literature, that the role of poorly liganded iron has been rather underappreciated in the past, and that in combination with peroxide and superoxide its activity underpins the behaviour of a great many physiological processes that degrade over time. Understanding these requires an integrative, systems-level approach that may lead to novel therapeutic targets.
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Affiliation(s)
- Douglas B Kell
- School of Chemistry and Manchester Interdisciplinary Biocentre, The University of Manchester, 131 Princess St, Manchester, M1 7DN, UK.
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231
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Doltcthinkova V, Lozanova S, Ivanova E, Popov K, Roumenin C. Electrokinetic Potential in B-Thalassemia Erythrocyte Membranes: Effect of Static Magnetic Field (2T). BIOTECHNOL BIOTEC EQ 2009. [DOI: 10.1080/13102818.2009.10818526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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232
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Hepatic iron overload and hepatocellular carcinoma. Cancer Lett 2008; 286:38-43. [PMID: 19081672 DOI: 10.1016/j.canlet.2008.11.001] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Accepted: 11/04/2008] [Indexed: 01/09/2023]
Abstract
The liver is the main storage site for iron in the body. Excess accumulation of iron in the liver has been well-documented in two human diseases, hereditary hemochromatosis and dietary iron overload in the African. Hepatic iron overload in these conditions often results in fibrosis and cirrhosis and may be complicated by the development of hepatocellular carcinoma. Malignant transformation usually occurs in the presence of cirrhosis, suggesting that free iron-induced chronic necroinflammatory hepatic disease plays a role in the hepatocarcinogenesis. However, the supervention of hepatocellular carcinoma in the absence of cirrhosis raises the possibility that ionic iron may also be directly hepatocarcinogenic. Support for this possibility is provided by a recently described animal model of dietary iron overload in which iron-free preneoplastic nodules and hepatocellular carcinoma developed in the absence of fibrosis or cirrhosis. The mechanisms by which iron induces malignant transformation have yet to be fully characterized but the most important appears to be the generation of oxidative stress. Free iron generates reactive oxygen intermediates that disrupt the redox balance of the cells and cause chronic oxidative stress. Oxidative stress leads to lipid peroxidation of unsaturated fatty acids in membranes of cells and organelles. Cytotoxic by-products of lipid peroxidation, such as malondialdehyde and 4-hydroxy-2'-nonenal, are produced and these impair cellular function and protein synthesis and damage DNA. Deoxyguanosine residues in DNA are also hydroxylated by reactive oxygen intermediates to form 8-hydroxy-2'-deoxyguanosine, a major promutagenic adduct that causes G:C to T:A transversions and DNA unwinding and strand breaks. Free iron also induces immunologic abnormalities that may decrease immune surveillance for malignant transformation.
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233
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Battin EE, Brumaghim JL. Metal specificity in DNA damage prevention by sulfur antioxidants. J Inorg Biochem 2008; 102:2036-42. [DOI: 10.1016/j.jinorgbio.2008.06.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Revised: 06/04/2008] [Accepted: 06/14/2008] [Indexed: 01/30/2023]
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234
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Panteleon V, Kostakis IK, Marakos P, Pouli N, Andreadou I. Synthesis and free radical scavenging activity of some new spiropyranocoumarins. Bioorg Med Chem Lett 2008; 18:5781-4. [DOI: 10.1016/j.bmcl.2008.09.065] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 09/16/2008] [Accepted: 09/17/2008] [Indexed: 12/13/2022]
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235
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Kitchin KT, Wallace K. Evidence against the nuclear in situ binding of arsenicals–oxidative stress theory of arsenic carcinogenesis. Toxicol Appl Pharmacol 2008; 232:252-7. [DOI: 10.1016/j.taap.2008.06.021] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Revised: 06/23/2008] [Accepted: 06/26/2008] [Indexed: 12/14/2022]
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236
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Smith PJ, Wiltshire M, Furon E, Beattie JH, Errington RJ. Impact of overexpression of metallothionein-1 on cell cycle progression and zinc toxicity. Am J Physiol Cell Physiol 2008; 295:C1399-408. [PMID: 18815222 DOI: 10.1152/ajpcell.00342.2008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Metallothioneins (MTs) have an important role in zinc homeostasis and may counteract the impact of oversupply. Both intracellular zinc and MT expression have been implicated in proliferation control and resistance to cellular stress, although the interdependency is unclear. The study addresses the consequences of a steady-state overexpression of MT-1 for intracellular zinc levels, cell cycle progression, and protection from zinc toxicity using a panel of cell lines with differential expression of MT-1. The panel comprised parental Chinese hamster ovary-K1 cells with low endogenous expression of MT and transfectants with enhanced expression of mouse MT-1 on an autonomously replicating expression vector with a noninducible promoter. Cell cycle progression, determined by flow cytometry and time-lapse microscopy, revealed that enhanced cytoplasmic expression of MT-1 does not impact on normal cell cycle operation, suggesting that basal levels of MT-1 expression are not limiting for background levels of oxidative stress. MT-1 overexpression correlated with a steady-state increase in cytoplasmic free Zn(2+), assessed using the fluorescent zinc-sensor Zinquin, particularly at high levels of overexpression, further suggesting that zinc availability is normally not limiting for cell cycle progression. Enhanced MT-1 expression, over a 10-fold range, had a clear impact on resistance to Cd(2+) and Zn(2+) toxicity. In the case of Zn(2+), the degree of protection afforded was less, indicating that MT-1 has a limited range and saturable capacity for effecting resistance. The results have implications for the use of cellular stress responses to exogenously supplied zinc and zinc-based systemic therapies.
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Affiliation(s)
- Paul J Smith
- Dept. of Pathology, Tenovus Bldg., School of Medicine, Cardiff Univ., Heath Park, Cardiff CF14 4XN, UK.
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237
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Wang D, Kim BY, Lee KS, Yoon HJ, Cui Z, Lu W, Jia JM, Kim DH, Sohn HD, Jin BR. Molecular characterization of iron binding proteins, transferrin and ferritin heavy chain subunit, from the bumblebee Bombus ignitus. Comp Biochem Physiol B Biochem Mol Biol 2008; 152:20-7. [PMID: 18824242 DOI: 10.1016/j.cbpb.2008.09.082] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Revised: 09/04/2008] [Accepted: 09/05/2008] [Indexed: 10/21/2022]
Abstract
Transferrin and ferritin are iron-binding proteins involved in transport and storage of iron as part of iron metabolism. Here, we describe the cDNA cloning and characterization of transferrin (Bi-Tf) and the ferritin heavy chain subunit (Bi-FerHCH), from the bumblebee Bombus ignitus. Bi-Tf cDNA spans 2340 bp and encodes a protein of 706 amino acids and Bi-FerHCH cDNA spans 1393 bp and encodes a protein of 217 amino acids. Comparative analysis revealed that Bi-Tf appears to have residues comprising iron-binding sites in the N-terminal lobe, and Bi-FerHCH contains a 5'UTR iron-responsive element and seven conserved amino acid residues associated with a ferroxidase center. The Bi-Tf and Bi-FerHCH cDNAs were expressed as 79 kDa and 27 kDa polypeptides, respectively, in baculovirus-infected insect Sf9 cells. Northern blot analysis revealed that Bi-Tf exhibits fat body-specific expression and Bi-FerHCH shows ubiquitous expression. The expression profiles of the Bi-Tf and Bi-FerHCH in the fat body of B. ignitus worker bees revealed that Bi-Tf and Bi-FerHCH are differentially induced in a time-dependent manner in a single insect by wounding, bacterial challenge, and iron overload.
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Affiliation(s)
- Dong Wang
- College of Natural Resources and Life Science, Dong-A University, Busan 604-714, Republic of Korea
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238
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Berg D, Riederer P, Gerlach M. Contribution of disturbed iron metabolism to the pathogenesis of Parkinson’s disease. FUTURE NEUROLOGY 2008. [DOI: 10.2217/14796708.3.4.447] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Extensive research has revealed a complex pathophysiology in Parkinson’s disease, with different factors contributing to the progressive neurodegeneration. Within this complex pathophysiology, a central role of iron and iron-induced oxidative stress has been discussed for many years, as elevated tissue iron levels, especially within the substantia nigra, have been detected by different techniques in a number of postmortem studies. These findings could be verified intra vitam by advancing MRI techniques, and more recently transcranial ultrasound. Different causes, such as disruption of the BBB, local changes in the normal iron-regulatory system, release of iron from intracellular storages or intraneuronal transportation from iron-rich areas, as well as genetic variations leading to changes in brain iron metabolism, are being discussed to be responsible for the increased tissue iron levels. Although it is still not clear whether increased iron levels constitute a primary or secondary phenomenon in the etiology of Parkinson’s disease, its interaction with many pathophysiologcial cascades and contribution to all forms of Parkinson’s disease, idiopathic as well as monogenetic, stresses the importance of further elucidating the mechanism of brain iron homeostasis and its possible alterations to finally develop pharmacological interventions that may disrupt the chain of pathological events leading to neurodegeneration.
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Affiliation(s)
- Daniela Berg
- Center of Neurology, Department of Neurodegeneration & Hertie Institute for Clinical Brain Research, 72076 Tübingen, Germany
| | - Peter Riederer
- University of Würzburg, Department of Psychiatry & Psychotherapy and, National Parkinson Foundation Centers of Excellence for Neurodegenerative Diseases Research, Laboratory for Clinical Neurochemistry, Würzburg, Germany
| | - Manfred Gerlach
- University of Würzburg, Department of Child & Adolescent Psychiatry & Psychotherapy, Laboratory for Clinical Neurobiology, Würzburg, Germany
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239
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Atif F, Kaur M, Ansari RA, Raisuddin S. Channa punctatabrain metallothionein is a potent scavenger of superoxide radicals and prevents hydroxyl radical‐inducedin vitroDNA damage. J Biochem Mol Toxicol 2008; 22:202-8. [DOI: 10.1002/jbt.20230] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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240
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MacKenzie EL, Ray PD, Tsuji Y. Role and regulation of ferritin H in rotenone-mediated mitochondrial oxidative stress. Free Radic Biol Med 2008; 44:1762-71. [PMID: 18325346 PMCID: PMC2682214 DOI: 10.1016/j.freeradbiomed.2008.01.031] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 12/20/2007] [Accepted: 01/26/2008] [Indexed: 12/21/2022]
Abstract
Tight regulation of intracellular iron levels in response to mitochondrial dysfunction is an important mechanism that prevents oxidative stress, thereby limiting cellular damage. Here, we describe a cytoprotective response involving transcriptional activation of the ferritin H gene in response to the mitochondrial complex I inhibitor and neurotoxic compound rotenone. Rotenone exposure increased ferritin H mRNA and protein synthesis in NIH3T3 fibroblasts and SH-SY5Y neuroblastoma cells. Transient transfection of a ferritin H promoter-luciferase reporter into NIH3T3 cells showed that ferritin H was transcriptionally activated by rotenone through an antioxidant-responsive element (ARE). Chromatin immunoprecipitation assays showed that rotenone treatment enhanced binding of Nrf2 and JunD transcription factors to the ARE. In addition, rotenone induced production of reactive oxygen species (ROS), and pretreatment with N-acetylcysteine abrogated ferritin H mRNA induction by rotenone, suggesting that this response is oxidative stress-mediated. Furthermore, reduced ferritin H expression by siRNA sensitized cells to rotenone-induced apoptosis with increased ROS production and annexin V-positive cells. Taken together, these results suggest that ferritin H transcription is activated by rotenone via an oxidative stress-mediated pathway leading to ARE activation and may be critically important to protect cells from mitochondrial dysfunction and oxidative stress.
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Affiliation(s)
- Elizabeth L MacKenzie
- Department of Environmental and Molecular Toxicology, North Carolina State University, Campus Box 7633, Raleigh, NC 27695, USA
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241
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Smietana M, Clayette P, Mialocq P, Vasseur JJ, Oiry J. Synthesis of new N-isobutyryl-L-cysteine/MEA conjugates: evaluation of their free radical-scavenging activities and anti-HIV properties in human macrophages. Bioorg Chem 2008; 36:133-40. [PMID: 18367231 DOI: 10.1016/j.bioorg.2008.02.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Revised: 02/11/2008] [Accepted: 02/12/2008] [Indexed: 10/22/2022]
Abstract
Four novel N-isobutyryl-L-cysteine/2-mercaptoethylamine (MEA, cysteamine) conjugates have been designed and synthesized. The antioxidant activities of these new series were evaluated by three different free radical scavenging methods (DPPH test, ABTS test, and deoxyribose assay) and their metal binding capacity was evaluated by the ethidium bromide fluorescence binding assay. These results were compared with those obtained with their pro-GSH acetyl analogues recently developed in our laboratory. We observed that most of these compounds exhibit free radical-scavenging activities similar to those of Trolox, but always superior than NAC. While none of these new derivatives had pro-GSH activities, they displayed anti-HIV properties in human monocyte-derived macrophages infected in vitro. The present study demonstrates that these new N-isobutyryl derivatives, which are expected to have a greater bioavailability than their acetyl analogues, may have useful applications in HIV infection in respect to their antioxidant and anti-HIV activities.
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Affiliation(s)
- Michael Smietana
- Institut des Biomolécules Max Mousseron, IBMM UMR 5247 CNRS, Université Montpellier 1, Université Montpellier 2, place Eugène Bataillon, 34095 Montpellier, France.
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242
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Kim BY, Lee KS, Choo YM, Kim I, Je YH, Woo SD, Lee SM, Park HC, Sohn HD, Jin BR. Insect transferrin functions as an antioxidant protein in a beetle larva. Comp Biochem Physiol B Biochem Mol Biol 2008; 150:161-9. [PMID: 18400534 DOI: 10.1016/j.cbpb.2008.02.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2008] [Revised: 02/19/2008] [Accepted: 02/21/2008] [Indexed: 10/22/2022]
Abstract
In insects transferrin is known as an iron transporter, an antibiotic agent, a vitellogenin, and a juvenile hormone regulated protein. Here, a novel functional role for insect transferrin as an antioxidant protein is demonstrated. Stressors, such as heat shock, fungal challenge, and H(2)O(2) exposure, cause upregulation of the white-spotted flower chafer Protaetia brevitarsis (Coleoptera: Scarabaeidae) transferrin (PbTf) mRNA in the fat body and increases PbTf protein levels in the hemolymph. RNA interference (RNAi) treated PbTf reduction causes increased iron and H(2)O(2) levels in the hemolymph and results in induction of apoptotic cell death in the fat body during exposure to stress. The observed effects of PbTf RNAi suggest that PbTf inhibits stress-induced apoptosis by diminishing the Fenton reaction via the binding of iron, thus supporting an antioxidant role for PbTf in stress responses.
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Affiliation(s)
- Bo Yeon Kim
- College of Natural Resources and Life Science, Dong-A University, Busan 604-714, South Korea
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243
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Boretsky YR, Protchenko OV, Prokopiv TM, Mukalov IO, Fedorovych DV, Sibirny AA. Mutations and environmental factors affecting regulation of riboflavin synthesis and iron assimilation also cause oxidative stress in the yeast Pichia guilliermondii. J Basic Microbiol 2008; 47:371-7. [PMID: 17910100 DOI: 10.1002/jobm.200610279] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Iron deficiency causes oversynthesis of riboflavin in several yeast species, known as flavinogenic yeasts. However, the mechanisms of such regulation are not known. We found that mutations causing riboflavin overproduction and iron hyperaccumulation (rib80, rib81 and hit1), as well as cobalt excess or iron deficiency all provoke oxidative stress in the Pichia guilliermondii yeast. Iron content in the cells, production both of riboflavin and malondialdehyde by P. guilliermondii wild type and hit1 mutant strains depend on a type of carbon source used in cultivation media. The data suggest that the regulation of riboflavin biosynthesis and iron assimilation in P. guilliermondii are linked with cellular oxidative state.
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Affiliation(s)
- Yuriy R Boretsky
- Department of Molecular Genetics and Biotechnology, Institute of Cell Biology NAS of Ukraine, Lviv, Ukraine
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244
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Ko C, Siddaiah N, Berger J, Gish R, Brandhagen D, Sterling RK, Cotler SJ, Fontana RJ, McCashland TM, Han SHB, Gordon FD, Schilsky ML, Kowdley KV. Prevalence of hepatic iron overload and association with hepatocellular cancer in end-stage liver disease: results from the National Hemochromatosis Transplant Registry. Liver Int 2007; 27:1394-401. [PMID: 17927713 DOI: 10.1111/j.1478-3231.2007.01596.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND It is unclear whether mild to moderate iron overload in liver diseases other than hereditary haemochromatosis (HH) contributes to hepatocellular carcinoma. This study examined the association between hepatic iron grade and hepatocellular carcinoma in patients with end-stage liver disease of diverse aetiologies. METHODS The prevalence of hepatic iron overload and hepatocellular carcinoma was examined in 5224 patients undergoing liver transplantation. Explant pathology reports were reviewed for the underlying pathological diagnosis, presence of hepatocellular carcinoma and degree of iron staining. The distribution of categorical variables was studied using chi(2) tests. RESULTS Both iron overload and hepatocellular carcinoma were the least common with biliary cirrhosis (1.8 and 2.8% respectively). Hepatocellular carcinoma was the most common in patients with hepatitis B (16.7%), followed by those with hepatitis C (15.1%) and HH (14.9%). In the overall cohort, any iron overload was significantly associated with hepatocellular carcinoma (P=0.001), even after adjustment for the underlying aetiology of liver disease. The association between hepatic iron content and hepatocellular carcinoma was the strongest in patients with biliary cirrhosis (P<0.001) and hepatitis C (P<0.001). CONCLUSIONS Iron overload is associated with hepatocellular carcinoma in patients with end-stage liver disease, suggesting a possible carcinogenic or cocarcinogenic role for iron in chronic liver disease.
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Affiliation(s)
- Cynthia Ko
- Division of Gastroenterology, University of Washington Medical Center, Seattle, WA, USA
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245
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Adam V, Beklova M, Pikula J, Hubalek J, Trnkova L, Kizek R. Shapes of Differential Pulse Voltammograms and Level of Metallothionein at Different Animal Species. SENSORS 2007; 7:2419-2429. [PMID: 28903235 PMCID: PMC3864530 DOI: 10.3390/s7102419] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Accepted: 10/17/2007] [Indexed: 11/16/2022]
Abstract
Metallothioneins play a key role in maintaining homeostasis of essential metals and in protecting of cells against metal toxicity as well as oxidative damaging. Excepting humans, blood levels of metallothionein have not yet been reported from any animal species. Blood plasma samples of 9 animal species were analysed by the adsorptive transfer stripping technique to obtain species specific voltammograms. Quite distinct records were obtained from the Takin (Budorcas taxicolor), while other interesting records were observed in samples from the European Bison (Bison bonasus bonasus) and the Red-eared Slider (Trachemys scripta elegans). To quantify metallothionein the catalytic peak Cat2 was used, well developed in the Domestic Fowl (Gallus gallus f. domestica) and showing a very low signal in the Red Deer (Cervus elaphus). The highest levels of metallothionein reaching over 20 µM were found in the Domestic Fowl. High levels of MT were also found in the Bearded Dragon (Pogona vitticeps) and the Grey Wolf (Canis lupus lupus). The lowest values of about 1-3 µM were determined in the Red-eared Slider, Takin and Red Deer. Employing a simple electrochemical detection it was possible to examine variation in blood metallothionein in different species of vertebrates.
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Affiliation(s)
- Vojtech Adam
- Department of Chemistry and BiochemistryMendel University of Agriculture and Forestry, Zemedelska 1, CZ-613 00 Brno, Czech Republic
| | - Miroslava Beklova
- Department of Veterinary Ecology and Environmental Protection, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Palackeho 1-3, CZ-612 42 Brno, Czech Republic
| | - Jiri Pikula
- Department of Veterinary Ecology and Environmental Protection, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Palackeho 1-3, CZ-612 42 Brno, Czech Republic
| | - Jaromir Hubalek
- Department of Microelectronics, Faculty of Electrical Engineering and Communication, Brno University of Technology, Udolni 53, CZ-602 00 Brno, Czech Republic
| | - Libuse Trnkova
- Department of Microelectronics, Faculty of Electrical Engineering and Communication, Brno University of Technology, Udolni 53, CZ-602 00 Brno, Czech Republic
| | - Rene Kizek
- Department of Chemistry and BiochemistryMendel University of Agriculture and Forestry, Zemedelska 1, CZ-613 00 Brno, Czech Republic.
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246
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Genotoxicity and mutagenicity of iron and copper in mice. Biometals 2007; 21:289-97. [DOI: 10.1007/s10534-007-9118-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Accepted: 09/11/2007] [Indexed: 10/22/2022]
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247
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Harrigan JA, Piotrowski J, Di Noto L, Levine RL, Bohr VA. Metal-catalyzed oxidation of the Werner syndrome protein causes loss of catalytic activities and impaired protein-protein interactions. J Biol Chem 2007; 282:36403-11. [PMID: 17911100 DOI: 10.1074/jbc.m706107200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Metal-catalyzed oxidation reactions target amino acids in the metal binding pocket of proteins. Such oxidation reactions generally result in either preferential degradation of the protein or accumulation of a catalytically inactive pool of protein with age. Consistently, levels of oxidized proteins have been shown to increase with age. The segmental, progeroid disorder Werner syndrome results from loss of the Werner syndrome protein (WRN). WRN is a member of the RecQ family of DNA helicases and possesses exonuclease and ATP-dependent helicase activities. Furthermore, each of the helicase and exonuclease domains of WRN contains a metal binding pocket. In this report we examined for metal-catalyzed oxidation of WRN in the presence of iron or copper. We found that WRN was oxidized in vitro by iron but not by copper. Iron-mediated oxidation resulted in the inhibition of both WRN helicase and exonuclease activities. Oxidation of WRN also inhibited binding to several known protein partners. In addition, we did not observe degradation of oxidized WRN by the 20 S proteasome in vitro. Finally, exposure of cells to hydrogen peroxide resulted in oxidation of WRN in vivo. Therefore, our results demonstrate that WRN undergoes metal-catalyzed oxidation in the presence of iron, and iron-mediated oxidation of WRN likely results in the accumulation of a catalytically inactive form of the protein, which may contribute to age-related phenotypes.
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Affiliation(s)
- Jeanine A Harrigan
- Laboratory of Molecular Gerontology, NIA, National Institutes of Health, Baltimore, Maryland 21224, USA
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248
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Campos E, Montella C, Garces F, Baldoma L, Aguilar J, Badia J. Aerobic l-ascorbate metabolism and associated oxidative stress in Escherichia coli. Microbiology (Reading) 2007; 153:3399-3408. [PMID: 17906139 DOI: 10.1099/mic.0.2007/009613-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The anaerobic utilization of L-ascorbate by gene products of the ula regulon in Escherichia coli has been widely documented. Under aerobic conditions, we have shown that this metabolism is only functional in the presence of casein acid hydrolysate. Transcriptional fusions and proteomic analysis indicated that both the ula regulon and the yiaK-S operon are required for the aerobic utilization of this compound. The aerobic dissimilation of l-ascorbate shares the function of three paralogous proteins, UlaD/YiaQ, UlaE/YiaR and UlaF/YiaS, which encode a decarboxylase, a 3-epimerase and a 4-epimerase, respectively. In contrast, l-ascorbate enters the cells through the ula-encoded phosphotransferase transport system, but it is not carried by the yiaMNO-encoded ABC transporter. Proteomic analysis also indicated enhanced expression of the alkyl hydroperoxide reductase encoded by the ahpC gene, suggesting a response to oxidative stress generated during the aerobic metabolism of l-ascorbate. Control of ahpC expression by the OxyR global regulator in response to l-ascorbate concentration is consistent with the formation of hydrogen peroxide under our experimental conditions. The presence of certain amino acids such as proline, threonine or glutamine in the culture medium allowed aerobic l-ascorbate utilization by Escherichia coli cells. This effect could be explained by the ability of these amino acids to allow yiaK-S operon induction by l-ascorbate, thus increasing the metabolic flux of l-ascorbate dissimilation. Alternatively, these amino acids may slow the rate of L-ascorbate oxidation.
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Affiliation(s)
- Evangelina Campos
- Department of Biochemistry, School of Pharmacy, University of Barcelona, Avda Diagonal 643, E-08028 Barcelona, Spain
| | - Cristina Montella
- Department of Biochemistry, School of Pharmacy, University of Barcelona, Avda Diagonal 643, E-08028 Barcelona, Spain
| | - Fernando Garces
- Department of Biochemistry, School of Pharmacy, University of Barcelona, Avda Diagonal 643, E-08028 Barcelona, Spain
| | - Laura Baldoma
- Department of Biochemistry, School of Pharmacy, University of Barcelona, Avda Diagonal 643, E-08028 Barcelona, Spain
| | - Juan Aguilar
- Department of Biochemistry, School of Pharmacy, University of Barcelona, Avda Diagonal 643, E-08028 Barcelona, Spain
| | - Josefa Badia
- Department of Biochemistry, School of Pharmacy, University of Barcelona, Avda Diagonal 643, E-08028 Barcelona, Spain
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249
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Lee IK, Jang YW, Yu SH, Yun BS. New triterpene glucosides, oligoporins A–C, from Oligoporus tephroleucus protect DNA from Fenton reaction. Bioorg Med Chem Lett 2007; 17:4906-9. [PMID: 17588752 DOI: 10.1016/j.bmcl.2007.06.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2007] [Revised: 06/05/2007] [Accepted: 06/08/2007] [Indexed: 11/30/2022]
Abstract
New triterpene glucosides, oligoporins A (1), B (2), and C (3), were isolated from the methanolic extract of the fruiting bodies of Oligoporus tephroleucus (Polyporaceae). Their structures were established by spectroscopic methods. These compounds significantly exhibited protective effect to plasmid DNA damage by hydroxyl radical (*OH) generated from the Fenton reaction with hydrogen peroxide and ferrous.
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Affiliation(s)
- In-Kyoung Lee
- Functional Metabolomics Research Center, KRIBB, Yuseong, Daejeon, Republic of Korea
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250
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Voloboueva LA, Killilea DW, Atamna H, Ames BN. N-tert-butyl hydroxylamine, a mitochondrial antioxidant, protects human retinal pigment epithelial cells from iron overload: relevance to macular degeneration. FASEB J 2007; 21:4077-86. [PMID: 17656467 PMCID: PMC2597693 DOI: 10.1096/fj.07-8396com] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of severe visual impairment in the elderly in developed countries. AMD patients have elevated levels of iron within the retinal pigment epithelia (RPE), which may lead to oxidative damage to mitochondria, disruption of retinal metabolism, and vision impairment or loss. As a possible model for iron-induced AMD, we investigated the effects of excess iron in cultured human fetal RPE cells on oxidant levels and mitochondrial cytochrome c oxidase (complex IV) function and tested for protection by N-tert-butyl hydroxylamine (NtBHA), a known mitochondrial antioxidant. RPE exposure to ferric ammonium citrate resulted in a time- and dose-dependent increase in intracellular iron, which increased oxidant production and decreased glutathione (GSH) levels and mitochondrial complex IV activity. NtBHA addition to iron-overloaded RPE cells led to a reduction of intracellular iron content, oxidative stress, and partial restoration of complex IV activity and GSH content. NtBHA might be useful in AMD due to its potential to reduce oxidative stress, mitochondrial damage, and age-related iron accumulation, which may damage normal RPE function and lead to loss of vision.
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Affiliation(s)
- Ludmila A Voloboueva
- Children's Hospital Oakland Research Institute, Nutrition and Metabolism Center, 5700 Martin Luther King Jr. Way, Oakland, CA 94609-1673, USA
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