Chondroitin 4-sulphate exhibits inhibitory effect during Cu2+-mediated LDL oxidation.
Chondroitin 4-sulphate (C4S), a basic component of the extracellular matrix of the artery wall, inhibited copper-induced low density lipoprotein (LDL) oxidation by prolonging the lag time and reducing the rate of propagation. LDL oxidation was assessed by monitoring conjugated dienes and low level chemiluminescence. A possible initial key reaction in LDL oxidation, the reduction of copper(II) to copper(I) by LDL, was decreased in the presence of C4S. Moreover, C4S protected tryptophan residues of Apo-B-100 in the early stage of LDL oxidation and during the subsequent propagation phase. The presence of the sulphate group in position 4 of N-acetylgalactosaminyl residues of C4S is crucial for protective activity. In fact, the structurally related chondroitin 6-sulphate, also present in tissues, had no effect on LDL oxidation. These data suggest that C4S may contribute to protect LDL against oxidation in arterial intima.
Albertini
R
R
Institute of Biochemistry, University of Graz, Austria.
Ramos
P
P
Giessauf
A
A
Passi
A
A
De Luca
G
G
Esterbauer
H
H
D000328:Adult; D002809:Chondroitin Sulfates / Q000494:pharmacology*; D003300:Copper / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007700:Kinetics; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008297:Male; D010084:Oxidation-Reduction; D014364:Tryptophan / Q000378:metabolism
D008077:Lipoproteins, LDL; D003300:Copper; D014364:Tryptophan; D002809:Chondroitin Sulfates