calcimycin and parinaric-acid

To investigate the role of oxidative functions in human osteoarthritic (OA) chondrocytes and to investigate the presence of in vivo molecular markers of lipoxidation in OA cartilage.. An in vitro model of cartilage collagen degradation was used. Lipid peroxidation activity and overall oxidative function in OA chondrocytes were monitored by cis-parinaric acid and dichlorofluorescein assays, respectively. In vivo molecular markers of lipoxidation in normal and OA cartilage were studied using immunohistochemistry to detect the presence of malondialdehyde and hydroxynonenal adducts.. Human OA chondrocytes showed a robust amount of 3H-proline-labeled collagen degradation upon stimulation with lipopolysaccharide and calcium ionophore A21387, as compared with that in untreated OA chondrocytes. Primary OA chondrocytes showed both spontaneous and inducible levels of lipid peroxidation activity. However, lipid peroxidation activity was already maximally elevated in more than 50% of the OA chondrocyte samples. Overall, spontaneous and inducible oxidative activities were observed in all OA samples. Immunohistochemical analysis of control OA tissue sections that were not treated with monoclonal antibody showed little immunoreactivity. OA cartilage sections treated with monoclonal antibodies showed specific immunoreactivity on the cartilage surface, at sites of OA lesions, at the pericellular matrix, and at intra- and intercellular matrices. Normal cartilage sections showed faint surface reactivity.. Our observations suggest that human OA chondrocytes demonstrate spontaneous and inducible cell-associated lipoxidative and nonlipoxidative activity. Lipoxidative activity appears to be enhanced in OA chondrocytes. The presence of molecular markers of in vivo lipid peroxidation was demonstrated in OA cartilage, suggesting its role in the pathogenesis of the disease.

Topics: Adult; Aged; Aldehydes; Antibodies, Monoclonal; Biomarkers; Calcimycin; Cartilage, Articular; Cells, Cultured; Chondrocytes; Collagen; Dose-Response Relationship, Drug; Fatty Acids, Unsaturated; Fluoresceins; Humans; Hydrogen Peroxide; Immunohistochemistry; Ionophores; Joints; Lipid Peroxidation; Lipopolysaccharides; Malondialdehyde; Middle Aged; Osteoarthritis

The effects of two polyunsaturated fatty acids, 18:4n-3 and 16:4n-3 purified from the marine algae, Undaria pinnatifida and Ulva pertusa, on icosanoid production in MC/9 mouse mast cells were assessed. Both fatty acids suppressed the production of leukotriene B4 (LTB4), leukotriene C4 (LTC4), and 5-hydroxyeicosatetraenoic acid (5-HETE). The order of the suppressive activity for the two marine algae-derived fatty acids and three other common polyunsaturated fatty acids was as follows; 22:6n-3 = 18:4n-3 = 18:3n-3 > 20:5n-3 = 16:4n-3 for LTB4; 22:6n-3 = 18:4n-3 = 18:3n-3 > 16:4n-3 > 20:5n-3 (no suppression) for LTC4; 22:6n-3 = 18:4n-3 > 18:3n-3 > 20:5n-3 = 16:4n-3 for 5-HETE.

Topics: Animals; Calcimycin; Chromatography, High Pressure Liquid; Eukaryota; Fatty Acids, Unsaturated; Hydroxyeicosatetraenoic Acids; Ionophores; Leukotriene B4; Leukotriene C4; Mast Cells; Mice; Plants, Edible