Degradation of hyaluronic acid, poly- and monosaccharides, and model compounds by hypochlorite: evidence for radical intermediates and fragmentation

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Degradation of hyaluronic acid, poly- and monosaccharides, and model compounds by hypochlorite : evidence for radical intermediates and fragmentation. / Hawkins, C L; Davies, Michael Jonathan.

In: Free Radical Biology & Medicine, Vol. 24, No. 9, 06.1998, p. 1396-410.

Research output: Contribution to journalJournal articleResearchpeer-review

Harvard

Hawkins, CL & Davies, MJ 1998, 'Degradation of hyaluronic acid, poly- and monosaccharides, and model compounds by hypochlorite: evidence for radical intermediates and fragmentation', Free Radical Biology & Medicine, vol. 24, no. 9, pp. 1396-410.

APA

Hawkins, C. L., & Davies, M. J. (1998). Degradation of hyaluronic acid, poly- and monosaccharides, and model compounds by hypochlorite: evidence for radical intermediates and fragmentation. Free Radical Biology & Medicine, 24(9), 1396-410.

Vancouver

Hawkins CL, Davies MJ. Degradation of hyaluronic acid, poly- and monosaccharides, and model compounds by hypochlorite: evidence for radical intermediates and fragmentation. Free Radical Biology & Medicine. 1998 Jun;24(9):1396-410.

Author

Hawkins, C L ; Davies, Michael Jonathan. / Degradation of hyaluronic acid, poly- and monosaccharides, and model compounds by hypochlorite : evidence for radical intermediates and fragmentation. In: Free Radical Biology & Medicine. 1998 ; Vol. 24, No. 9. pp. 1396-410.

Bibtex

@article{6313b1448d1947be86de8d3875a1e94b,
title = "Degradation of hyaluronic acid, poly- and monosaccharides, and model compounds by hypochlorite: evidence for radical intermediates and fragmentation",
abstract = "Degradation of hyaluronic acid by oxidants such as HO. and HOCl/CIO- is believed to be important in the progression of rheumatoid arthritis. While reaction of hyaluronic acid with HO. has been investigated extensively, reaction with HOCl/ClO- is less well defined. Thus, little is known about the site(s) of HOCl/ClO- attack, the intermediates formed, or the mechanism(s) of polymer degradation. In this study reaction of HOCl/ClO- with amides, sugars, polysaccharides, and hyaluronic acid has been monitored by UV-visible (220-340 nm) and EPR spectroscopy. UV-visible experiments have shown that HOCl/ClO- reacts preferentially with N-acetyl groups. This reaction is believed to give rise to transient chloramide (R-NCl-C(O)-R') species, which decompose rapidly to give radicals via either homolysis (to produce N. and Cl.) or heterolysis (one-electron reduction, to give N. and Cl.) of the N--C bond. The nature of the radicals formed has been investigated by EPR spin trapping. Reaction of HOCl/ClO- with hyaluronic acid, chondroitin sulphates A and C, N-acetyl sugars, and amides gave novel, carbon-centered, spin adducts, the formation of which is consistent with selective initial attack at the N-acetyl group. Thus, reaction with hyaluronic acid and chondroitin sulphate A, appears to be localized at the N-acetylglucosamine sugar rings. These carbon-centered radicals are suggested to arise from rapid rearrangement of initial nitrogen-centered radicals, formed from the N-acetyl chloramide, by reactions analogous to those observed with alkoxyl radicals. The detection of increasing yields of low-molecular-weight radical adducts from hyaluronic acid and chondroitin sulphate A with increasing HOCl/ClO-concentrations suggests that formation of the initial nitrogen-centered species on the N-acetylglucosamine rings, and the carbon-centered radicals derived from them, brings about polymer fragmentation.",
keywords = "Acetamides, Electron Spin Resonance Spectroscopy, Ferrous Compounds, Free Radicals, Hyaluronic Acid, Hydroxyl Radical, Hypochlorous Acid, Monosaccharides, Oxidation-Reduction, Polysaccharides, Spectrophotometry, Ultraviolet, Spin Trapping",
author = "Hawkins, {C L} and Davies, {Michael Jonathan}",
year = "1998",
month = "6",
language = "English",
volume = "24",
pages = "1396--410",
journal = "Free Radical Biology & Medicine",
issn = "0891-5849",
publisher = "Elsevier",
number = "9",

}

RIS

TY - JOUR

T1 - Degradation of hyaluronic acid, poly- and monosaccharides, and model compounds by hypochlorite

T2 - evidence for radical intermediates and fragmentation

AU - Hawkins, C L

AU - Davies, Michael Jonathan

PY - 1998/6

Y1 - 1998/6

N2 - Degradation of hyaluronic acid by oxidants such as HO. and HOCl/CIO- is believed to be important in the progression of rheumatoid arthritis. While reaction of hyaluronic acid with HO. has been investigated extensively, reaction with HOCl/ClO- is less well defined. Thus, little is known about the site(s) of HOCl/ClO- attack, the intermediates formed, or the mechanism(s) of polymer degradation. In this study reaction of HOCl/ClO- with amides, sugars, polysaccharides, and hyaluronic acid has been monitored by UV-visible (220-340 nm) and EPR spectroscopy. UV-visible experiments have shown that HOCl/ClO- reacts preferentially with N-acetyl groups. This reaction is believed to give rise to transient chloramide (R-NCl-C(O)-R') species, which decompose rapidly to give radicals via either homolysis (to produce N. and Cl.) or heterolysis (one-electron reduction, to give N. and Cl.) of the N--C bond. The nature of the radicals formed has been investigated by EPR spin trapping. Reaction of HOCl/ClO- with hyaluronic acid, chondroitin sulphates A and C, N-acetyl sugars, and amides gave novel, carbon-centered, spin adducts, the formation of which is consistent with selective initial attack at the N-acetyl group. Thus, reaction with hyaluronic acid and chondroitin sulphate A, appears to be localized at the N-acetylglucosamine sugar rings. These carbon-centered radicals are suggested to arise from rapid rearrangement of initial nitrogen-centered radicals, formed from the N-acetyl chloramide, by reactions analogous to those observed with alkoxyl radicals. The detection of increasing yields of low-molecular-weight radical adducts from hyaluronic acid and chondroitin sulphate A with increasing HOCl/ClO-concentrations suggests that formation of the initial nitrogen-centered species on the N-acetylglucosamine rings, and the carbon-centered radicals derived from them, brings about polymer fragmentation.

AB - Degradation of hyaluronic acid by oxidants such as HO. and HOCl/CIO- is believed to be important in the progression of rheumatoid arthritis. While reaction of hyaluronic acid with HO. has been investigated extensively, reaction with HOCl/ClO- is less well defined. Thus, little is known about the site(s) of HOCl/ClO- attack, the intermediates formed, or the mechanism(s) of polymer degradation. In this study reaction of HOCl/ClO- with amides, sugars, polysaccharides, and hyaluronic acid has been monitored by UV-visible (220-340 nm) and EPR spectroscopy. UV-visible experiments have shown that HOCl/ClO- reacts preferentially with N-acetyl groups. This reaction is believed to give rise to transient chloramide (R-NCl-C(O)-R') species, which decompose rapidly to give radicals via either homolysis (to produce N. and Cl.) or heterolysis (one-electron reduction, to give N. and Cl.) of the N--C bond. The nature of the radicals formed has been investigated by EPR spin trapping. Reaction of HOCl/ClO- with hyaluronic acid, chondroitin sulphates A and C, N-acetyl sugars, and amides gave novel, carbon-centered, spin adducts, the formation of which is consistent with selective initial attack at the N-acetyl group. Thus, reaction with hyaluronic acid and chondroitin sulphate A, appears to be localized at the N-acetylglucosamine sugar rings. These carbon-centered radicals are suggested to arise from rapid rearrangement of initial nitrogen-centered radicals, formed from the N-acetyl chloramide, by reactions analogous to those observed with alkoxyl radicals. The detection of increasing yields of low-molecular-weight radical adducts from hyaluronic acid and chondroitin sulphate A with increasing HOCl/ClO-concentrations suggests that formation of the initial nitrogen-centered species on the N-acetylglucosamine rings, and the carbon-centered radicals derived from them, brings about polymer fragmentation.

KW - Acetamides

KW - Electron Spin Resonance Spectroscopy

KW - Ferrous Compounds

KW - Free Radicals

KW - Hyaluronic Acid

KW - Hydroxyl Radical

KW - Hypochlorous Acid

KW - Monosaccharides

KW - Oxidation-Reduction

KW - Polysaccharides

KW - Spectrophotometry, Ultraviolet

KW - Spin Trapping

M3 - Journal article

C2 - 9641257

VL - 24

SP - 1396

EP - 1410

JO - Free Radical Biology & Medicine

JF - Free Radical Biology & Medicine

SN - 0891-5849

IS - 9

ER -

ID: 138283921