Mechanism of anti-inflammatory action of liquorice extract and glycyrrhizin.

The antiradical activity, protective effect against lipid peroxidation of liposomal membrane, and inhibitory effect on whole blood reactive oxygen species (ROS) liberation of Glycyrrhiza glabra crude extract and glycyrrhizin, its major compound, were assessed. The liquorice extract showed significant activity in all the three assay systems used in a dose dependent manner. It displayed remarkable reactivity with free stable 1,1'-diphenyl-2-picrylhydrazyl (DPPH) radical, inhibitory efficacy in peroxidatively damaged unilamellar dioleoyl phosphatidylcholine (DOPC) liposomes, and inhibition of ROS chemiluminescence, generated by whole blood, induced by both receptor-bypassing stimuli (PMA) and receptor operating stimuli (Opz) in the ranking order of stimuli PMA> Opz.

Effect of stobadine on opsonized zymosan stimulated generation of reactive oxygen species in human blood cells.

To predict more precisely the effect of stobadine, a pyridoindole antioxidant agent, in the whole organism, we studied its effect on opsonized zymosan-stimulated free radical generation in whole blood, on superoxide generation in the mixture of PMNL : platelets (1:50), as well as on superoxide generation and myeloperoxidase release in isolated PMNL. Without stimulation, stobadine had no effect on reactive oxygen species (ROS) generation and myeloperoxidase release. Stobadine in a concentration of 10 or 100 micromol/l significantly decreased luminol-enhanced chemiluminescence in opsonized zymosan-stimulated whole blood.

Reactive oxygen metabolite production is inhibited by histamine and H1-antagonist dithiaden in human PMN leukocytes.

The study evaluated the distinction between extracellular and intracellular production of reactive oxygen metabolites (ROM) in isolated polymorphonuclear leukocytes (PMNL) stimulated with opsonised zymosan (OZ) and investigated its modulation by the endogenous mediator histamine (0.1-100 mumol/l) and by the H1-antagonist dithiaden (1-100 mumol/l). For this observation, a modified luminol and an isoluminol amplified chemiluminescence (CL) technique were used.

Streptozotocin-induced experimental diabetes in male Wistar rats.

The aim of the present work was to test the sensitivity of young male Wistar rats, Dobrá Voda (Dv:WI) to the diabetogenic effect of streptozotocin (STZ) with regard to their health condition and mortality rates. Eight-week-old rats, weighing from 200 to 230 g, were randomised into five groups of eight animals. Streptozotocin was administered by i.

Reactive oxygen species induced smooth muscle responses in the intestine, vessels and airways and the effect of antioxidants.

Numerous experimental data confirm the importance of reactive oxygen species (ROS) in physiological activities of smooth muscles and in the pathogenesis of various diseases with altered function of smooth muscles. The present study shows that smooth muscles of the intestine, airways and vessels, as well as their epithelium, endothelium and innervations, might be important targets of the ROS action. We demonstrated differences among the actions of various ROS (endogenous, exogenous, produced enzymatically, non-enzymatically) as well as among their actions in different smooth muscle tissues.

Effect of ultrasonicated carboxymethylglucan on cyclophosphamide induced mutagenicity.

Carboxymethylglucan (CMG) with ultrasonically lowered molecular weight (0.89 x 10(5)) was administered either intraperitoneally, intravenously or orally prior to cyclophosphamide (CP) injection and its effect on the frequency of micronuclei in mouse bone marrow was evaluated. Both parenteral (intraperitoneal and intravenous) and oral administration of CMG decreased the clastogenic effect of CP.