thromboplastin and 1-1-diphenyl-2-picrylhydrazyl

This study was attempted to investigate antioxidant and antithrombus activities of water and methanol extracts of enzyme-treated Salicornia herbacea (SH)by in vitro assays observing the inhibitory activity of a rat liver microsomal lipid peroxidation, DPPH radical scavenging activity, activated partial thromboplastin times (APTT) and thromboplastin times (TT). The water and methanol extracts from enzyme-treated SH inhibited the lipid peroxidation in a dose-dependent manner over a concentration range of 0.1-1.0 mg/ml. The activity of enzyme-treated water and methanol extracts was stronger than that of non-enzyme-treated water and methanol extracts. The inhibitory activity of the water extract was higher at a concentration of 1.0 mg/ml than that of the methanol extract. The activity was the highest in the enzyme-treated water extract, and was approximately 1.08 times higher than alpha-tocopherol, a natural antioxidant. The DPPH radical scavenging activities of the SH extracts were similar to their lipid peroxidation inhibitory activity. The APTT of the water and methanol extracts was delayed at a concentration range of 0.25-2.0 mg/ml in a dose-dependent manner. The APTT of the methanol extract was longer at a concentration of 1.0 mg/ml than that of the water extracts. The enzyme-treated methanol extract exhibited the longest APTT even at a concentration of 0.50 mg/ml. The TT activities of the SH extracts were also similar to their APTT activities. These results suggest that water and methanol extracts of the enzyme-treated SH may be useful as potential antioxidant and antithrombus sources, respectively.

Topics: Animals; Antioxidants; Area Under Curve; Biphenyl Compounds; Chenopodiaceae; Dose-Response Relationship, Drug; Enzymes; Fibrinolytic Agents; Free Radical Scavengers; Humans; Hydrazines; Lipid Peroxidation; Liver; Methanol; Oxidation-Reduction; Partial Thromboplastin Time; Picrates; Plant Extracts; Rats; Rats, Sprague-Dawley; Thromboplastin; Water

The oxidative modification of LDL may play an important role in the early events of atherogenesis. Thus the identification of antioxidative compounds may be of therapeutic and prophylactic importance regarding cardiovascular disease. Copper-chlorophyllin (Cu-CHL), a Cu(2+)-protoporphyrin IX complex, has been reported to inhibit lipid oxidation in biological membranes and liposomes. Hemin (Fe(3+)-protoporphyrin IX) has been shown to bind to LDL thereby inducing lipid peroxidation. As Cu-CHL has a similar structure as hemin, one may assume that Cu-CHL may compete with the hemin action on LDL. Therefore, in the present study Cu-CHL and the related compound magnesium-chlorophyllin (Mg-CHL) were examined in their ability to inhibit LDL oxidation initiated by hemin and other LDL oxidizing systems. LDL oxidation by hemin in presence of H(2)O(2) was strongly inhibited by both CHLs. Both chlorophyllins were also capable of effectively inhibiting LDL oxidation initiated by transition metal ions (Cu(2+)), human umbilical vein endothelial cells (HUVEC) and tyrosyl radicals generated by myeloperoxidase (MPO) in presence of H(2)O(2) and tyrosine. Cu- and Mg-CHL showed radical scavenging ability as demonstrated by the diphenylpicrylhydracylradical (DPPH)-radical assay and estimation of phenoxyl radical generated diphenyl (dityrosine) formation. As assessed by ultracentrifugation the chlorophyllins were found to bind to LDL (and HDL) in serum. The present study shows that copper chlorophyllin (Cu-CHL) and its magnesium analog could act as potent antagonists of atherogenic LDL modification induced by various oxidative stimuli. As inhibitory effects of the CHLs were found at concentrations as low as 1 mumol/l, which can be achieved in humans, the results may be physiologically/therapeutically relevant.

Topics: Atherosclerosis; Biphenyl Compounds; Cardiovascular Diseases; Catalysis; Cells, Cultured; Chlorophyll; Chlorophyllides; Copper; Dose-Response Relationship, Drug; Endothelium, Vascular; Free Radical Scavengers; Free Radicals; Hemin; Humans; Hydrazines; Hydrogen Peroxide; Ions; Iron; Lipid Peroxidation; Lipids; Lipoproteins; Lipoproteins, LDL; Magnesium; Malondialdehyde; Models, Chemical; Octanols; Oxygen; Picrates; Protoporphyrins; Pyrazoles; Pyrimidines; Thiobarbituric Acid Reactive Substances; Thromboplastin; Time Factors; Tyrosine; Umbilical Veins; Water