Effects of a semi-synthetic N-,O-sulfated glycosaminoglycan K5 polysaccharide derivative in a rat model of cerebral ischaemia/reperfusion injury.
Heparin and low molecular weight heparins may reduce brain damage evoked by ischaemia/reperfusion (I/R) injury, although their use is hampered by the risk of haemorrhage. Chemical and enzymatic modifications of K5 polysaccharide have shown the possibility to produce heparin-like compounds with low anticoagulant activity and strong anti-inflammatory effects. Using a rat model of transient cerebral I/R, we investigated the effects of an epimerised N-,O-sulfated K5 polysaccharide derivative, K5-N,OSepi, on the infarct size, motor activity and injury caused by ischaemia (30 min) and reperfusion. Reperfusion was allowed for 60 min or 1-5 days. Rats reperfused for 5 days showed an infarct volume of 30.7 +/- 3.1% and K5-N,OSepi (0.1-1 mg/kg) caused dose-dependent reduction in infarct size (maximum at 1 mg/kg: 13.1 +/- 2.1% infarct volume). This effect was associated with a significant improvement in motor performance. In the rat hippocampus, one of the brain areas most sensitive to I/R injury, I/R induced a robust increase in myeloperoxidase (MPO) activity, a marker of neutrophil infiltration, that was halved by K5-N,OSepi administration (66.38 +/- 7.75 microU MPO/tissue g, 30.78 +/- 5.67 microU MPO/tissue g, respectively). K5-N,OSepi drastically reduced the expression of cyclooxygenase-2, inducible-nitric-oxide-synthase and intercellular-adhesion-molecule-1. I/R-induced activation of nuclear factor-kB was attenuated by drug treatment. Furthermore, K5-N,OSepi administration was associated with a significant modulation of apoptosis markers, such as Bid and Bcl-2. In conclusion, the results demonstrated that the sulfated semi-synthetic K5 derivative K5-N,OSepi protects the brain against I/R injury by disrupting multiple levels of the apoptotic and inflammatory cascade, including inhibition of NF-kappaB activation.
Collino
Massimo
M
Department of Anatomy, University of Turin, Torino, Italy. massimo.collino@unito.it
Castiglia
Sara
S
Manoni
Marco
M
Salsini
Liana
L
Chini
Jacopo
J
Masini
Emanuela
E
Fantozzi
Roberto
R
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000138:chemical synthesis / Q000494:pharmacology / Q000627:therapeutic use*; D000925:Anticoagulants / Q000138:chemical synthesis / Q000494:pharmacology / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects; D051023:BH3 Interacting Domain Death Agonist Protein / Q000096:biosynthesis / Q000235:genetics; D001925:Brain Damage, Chronic / Q000209:etiology / Q000517:prevention & control; D002545:Brain Ischemia / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000096:biosynthesis / Q000235:genetics; D004353:Drug Evaluation, Preclinical; D006624:Hippocampus / Q000098:blood supply / Q000187:drug effects / Q000473:pathology; D007249:Inflammation / Q000517:prevention & control; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D009504:Neutrophils / Q000201:enzymology; D052247:Nitric Oxide Synthase Type II / Q000096:biosynthesis / Q000235:genetics; D011134:Polysaccharides / Q000138:chemical synthesis / Q000494:pharmacology / Q000627:therapeutic use*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis / Q000235:genetics; D011597:Psychomotor Performance / Q000187:drug effects; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000188:drug therapy* / Q000473:pathology; D051996:Transcription Factor RelA / Q000037:antagonists & inhibitors
D000893:Anti-Inflammatory Agents; D000925:Anticoagulants; D051023:BH3 Interacting Domain Death Agonist Protein; C494816:Bid protein, rat; D011134:Polysaccharides; D019253:Proto-Oncogene Proteins c-bcl-2; C498145:Rela protein, rat; D051996:Transcription Factor RelA; D018799:Intercellular Adhesion Molecule-1; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D051546:Cyclooxygenase 2; C489691:Ptgs2 protein, rat