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Respiratory burst leads polymorphonuclear neutrophils (PMN) to produce reactive oxygen species (ROS) such as superoxide anions (O2°−), hypochlorous acid (HOCl) and hydrogen peroxide (H2O2) which may possess deleterious effects for the organism. Rosa caninafruits are well known to contain a large amount of vitamin C which is antioxidant. This study was focused on the polyphenolics contained in rose hips to evaluate their antioxidative properties.  We prepared a rose hip extract deprived of vitamin C. The extract contained mainly phenolics such as proanthocyanidins and flavonoids. We investigated its effects directly against O2°−, HOCl and H2O2and investigated its effects on isolated PMN. For that, in vitroinflammatory conditions were reproduced by stimulating PMN with stimuli having different transductional pathways, in order to determine a possible mechanism of action.  The results showed that the extract can inhibit ROS tested in acellular and cellular systems. The IC50obtained were 5.73 mg/L, 1.33 mg/L and 2.34 mg/L respectively for O2°−, HOCl and H2O2in acellular experiments. For cellular experiments, the IC50were quite similar. Thus, the extract did not present an effect on PMN metabolism. Therefore, the antioxidative effects of Rosa caninaare due not only to vitamin C but also to polyphenolics. Copyright © 2002 John Wiley & Sons, Ltd.

A reinvestigation of the stem bark of Cleistopholis glauca yielded 14 compounds, of which seven were either novel or had not been previously reported from this species. These were identified as the farnesane sesquiterpene methyl-(2E,6E)-10-oxo-3,7,11-trimethyl-dodeca-2,6-dienoate (1); the azaanthracene alkaloid cleistopholine (4); two partially acetylated oligorhamnoside derivatives, 1-O-dodecanyl-2,3,4-tri-O-acetyl-α-rhamnopyranosyl-(1→3)-2,4-di-O-acetyl-α-rhamnopyranosyl-(1→3)-4-O-acetyl-α-rhamnopyranosyl-(1→4)-α-rhamnopyranoside (6) and 1-O-dodecanyl-2,4-di-O-acetyl-α-rhamnopyranosyl-(1→3)-2,4-di-O-acetyl-α-rhamnopyranosyl-(1→3)-4-O-acetyl-α-rhamnopyranosyl-(1→4)-α-rhamnopyranoside (8), for which the trivial names cleistetroside-7 and cleistetroside-6 were assigned, respectively; the dihydrobenzofuran neolignan rel-(2α,3β)-7-O-methylcedrusin (12); and the flavonoids dihydroquercetin (13) and quercetin (14). Structure assignments of all compounds were established by spectroscopic methods and comparison with published data. The chemosystematic significance of the occurrence of the isolated components is mentioned. Compounds 1, 6, and 8 are novel natural products.

Twelve patients suffering from rheumatoid arthritis and having swollen knees were treated with 1.1 g/day of sodium naproxen administered in one dose, daily for 5 days.