Polyanions and their complexes. Part III. Reactions of heparin, hyaluronic acid, sodium poly(ethylenesulphonate), sodium poly(styrenesulphonate), and sodium carboxymethylcellulose with hydroxyl radicals and hydrated electrons

Balazs, Endre A.; Davies, Julie; Phillips, Glyn O.; Scheufele, D. S.

doi:10.1039/j39680001420

Cited by 20 publications

(10 citation statements)

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“…The measurement of rate constants for reactions (11) and (12) should not be affected by any low levels of oxygen. In these experiments, both [48]. Within the error limits, hydroxyl radicals have been shown to react with HACl in the current study at a similar rate to HA itself, indicating that the N-Cl group is not a more specific target than N-H.…”

Section: Oxidation By Hydroxyl Radicalssupporting

confidence: 53%

One-electron oxidation and reduction of glycosaminoglycan chloramides: A kinetic study

Sibanda

Parsons

Houée-Levin⊥

et al. 2013

Free Radical Biology and Medicine

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Hypochlorous acid and its acid-base counterpart, hypochlorite ions, produced in inflammatory conditions, may produce chloramides of glycosaminoglycans, the latter being significant components of the extracellular matrix (ECM). This may occur through the binding of myeloperoxidase directly to the glycosaminoglycans.The N-Cl group in the chloramides is a potential selective target for both reducing and oxidising radicals, leading possibly to more efficient and damaging fragmentation of these biopolymers relative to the parent glycosaminoglycans. In this study,the fast reaction techniques of pulse radiolysis and nanosecond laser flash photolysis have been used to generate both oxidizing and reducing radicals to react with the chloramides of hyaluronan (HACl) and heparin (HepCl).The strong reducing formate radicals and hydrated electrons were found to react rapidly with both HACl and HepCl with rate constants of (1-1.7) x 10 8 M -1 s -1 and (0.7-1.2) x 10 8 M -1 s -1 for formate radicals and 2.2 x 10 9 M -1 s and 7.2 x 10 8 M -1 s -1 for hydrated electrons, respectively. The spectral characteristics of the products of these reactions were identical and were consistent with initial attack at the N-Cl groups, followed by elimination of chloride ions to produce nitrogencentred radicals, which re-arrange subsequently and rapidly to produce C-2 radicals on the glucosamine moiety supporting an earlier EPR study by Rees et 3 This is the first study therefore to conclusively demonstrate that reducing radicals react rapidly with glycosaminoglycan chloramides in a site-specific attack at the N-Cl groups, probably to produce a 100 % efficient biopolymer fragmentation process. Although less reactive, carbonate radicals, which may be produced in vivo via reactions of peroxynitrite with serum levels of carbon dioxide ,also appear to react in a highly site-specific manner at the N-Cl group. It is not yet known if such site-specific attacks by this important in vivo species lead to a more efficient fragmentation of the biopolymers than would be expected for attack by the stronger oxidising species, the hydroxyl radical. It is clear however that the N-Cl group formed in inflammatory conditions in the extracellular matrix does present a more likely target for both reactive oxygen species and for reducing species than the N-H groups in the parent glycosaminoglycans. Graphical abstract4

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Section: Oxidation By Hydroxyl Radicalssupporting

confidence: 53%

One-electron oxidation and reduction of glycosaminoglycan chloramides: A kinetic study

Sibanda

Parsons

Houée-Levin⊥

et al. 2013

Free Radical Biology and Medicine

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“…Its clinical utility is of particular significance in treatment of osteoarthritis [89, 95-97, 100]. The anti-inflammatory capabilities of HA are mediated, at least in large part, by its antioxidant activity [101-108]. Promotion of the wound healing by HA may also be facilitated by similar antioxidant mechanisms [109, 110].…”

Section: Protection Of Dna From Oxidative Damage By Hyaluronanmentioning

confidence: 99%

“…The second mechanism by which HA may attenuate damage induced by oxidants involves the direct scavenging of oxidant molecules, particularly the reactive products of Fenton's reaction OH* radicals, by HA [101, 103, 116]. Of note, HA from synovial fluid was shown to have greater ROS-removing activity and scavenged more diverse range of ROS compared to other antioxidants such as catalase or superoxide dismutase (SOD) [103].…”

Section: Mechanisms Of Cell Protection From Oxidative Damage By Hamentioning

confidence: 99%

Genome integrity, stem cells and hyaluronan

Darżynkiewicz

Balazs²

2012

Aging

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Faithful preservation of genome integrity is the critical mission of stem cells as well as of germ cells. Reviewed are the following mechanisms involved in protecting DNA in these cells: (a) The efflux machinery that can pump out variety of genotoxins in ATP-dependent manner; (b) the mechanisms maintaining minimal metabolic activity which reduces generation of reactive oxidants, by-products of aerobic respiration; (c) the role of hypoxic niche of stem cells providing a gradient of variable oxygen tension; (d) (e) the presence of hyaluronan (HA) and HA receptors on stem cells and in the niche; (f) the role of HA in protecting DNA from oxidative damage; (g) the specific function of HA in protecting DNA in stem cells; (h) the interactions of HA with sperm cells and oocytes that also may shield their DNA from oxidative damage, and (e) mechanisms by which HA exerts the anti-oxidant activity. While HA has multitude of functions its anti-oxidant capabilities are often overlooked but may be of significance in preservation of integrity of stem and germ cells genome.

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“…Using the pulse radiolysis technique, and using nitrous oxide saturated solutions to convert hydrated electrons into hydroxyl radicals, the second-order rate constants for the reaction of hydroxyl radicals with any substrate can be determined. In this early study, the rate constant for the reaction of hydroxyl radicals with heparin was found to be 2.2 9 10 8 M -1 s -1 (Balazs et al 1968). A similar pulse radiolysis study on hyaluronan yielded a value of 7 9 10 8 M -1 s -1 (Myint et al 1987).…”

Section: Pulse Radiolysis and Laser Flash Photolysismentioning

confidence: 81%

“…One of the earliest kinetic studies of the reaction of oxidative species with hyaluronan was a pulse radiolysis study initiated by Professor Phillips (Balazs et al 1968). In pulse radiolysis, a short pulse (usually 5-100 ns) of high energy electrons (2-10 MeV) is given to a quartz cell containing an aqueous solution containing various solutes under investigation.…”

Section: Pulse Radiolysis and Laser Flash Photolysismentioning

confidence: 99%

Free radical studies of components of the extracellular matrix: contributions to protection of biomolecules and biomaterials from sterilising doses of ionising radiation

Parsons

2017

Cell Tissue Bank

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The purpose of the current review is show how the principles and techniques of radiation chemistry have enabled the direct reactions of free radicals with biomolecules and biomaterials to be investigated at the molecular level. In particular, the review focusses on the free radical-induced fragmentation of glycosaminoglycans. Glycosaminoglycans are large linear polysaccharides consisting of repeating disaccharide units and are important components of the extracellular matrix (ECM) either in free form (hyaluronan) or as a component of proteoglycans. Oxidative damage of the extracellular matrix components by either enzymatic or non-enzymatic pathways may have implications for the initiation and progression of a range of human diseases. These include arthritis, kidney disease, cardiovascular disease, lung disease, periodontal disease and chronic inflammation. Oxidative damage to hyaluronan by reactive oxidative species and thus the potential mechanism of damage to the ECM and its role in human pathologies is reviewed with particular focus on damage initiated by potential in vivo free radicals such as superoxide, carbonate and hydroxyl radicals. Such knowledge has also allowed radiation protecting systems to be developed so that sterilising doses of radiation can be delivered to sensitive biomolecules such as proteins and glycosaminoglycans, and also to sensitive biomaterials such as tissue allografts.

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Polyanions and their complexes. Part III. Reactions of heparin, hyaluronic acid, sodium poly(ethylenesulphonate), sodium poly(styrenesulphonate), and sodium carboxymethylcellulose with hydroxyl radicals and hydrated electrons

Cited by 20 publications

References 0 publications

One-electron oxidation and reduction of glycosaminoglycan chloramides: A kinetic study

One-electron oxidation and reduction of glycosaminoglycan chloramides: A kinetic study

Genome integrity, stem cells and hyaluronan

Free radical studies of components of the extracellular matrix: contributions to protection of biomolecules and biomaterials from sterilising doses of ionising radiation

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