No abstract

In this study, it was shown that abietic acid, an abietane diterpenoid, inhibited soybean 5-lipoxygenase (linoleate: oxygen oxidoreductase, EC 1.13.11.12) and an IC(50) of 29.5 +/- 1.29 microM was determined. Since the lipoxygenase pathway leads to the biosynthesis of leukotrienes this result supports the view that abietic acid may be used in the treatment of allergic reactions.

Oxidative stress decreases the deformability of erythrocytes. Anti-oxidant measures may alleviate, pro-oxidative damage may augment this decrease. Melatonin is reported to exert both anti-oxidant and pro-oxidant properties on erythrocytes. The aim of the present study was to evaluate the effects of melatonin on erythrocyte deformability under oxidative stress conditions induced by the combination of hydrogen peroxide (20 mM) and sodium azide (100 µM). Erythrocyte suspensions were incubated for 10 min with melatonin (1-1000 µM) prior to oxidative stress. Erythrocyte deformability was measured by Laser-assisted Optical Rotational Cell Analyzer (LORCA). Lipid peroxidation was determined via malondialdehyde (MDA) measurements by HPLC. Melatonin alone did not change erythrocyte deformability. Oxidative stress alone decreased the deformability of erythrocytes by 25.8 ± 3.1% (P < 0.05). Melatonin pre-treatment augmented the decrease in erythrocyte deformability but prevented lipid peroxidation. Melatonin (1 µM) did not cause any additional effect on erythrocyte deformability. Higher concentrations (10-1000 µM) further decreased deformability (P < 0.05). Erythrocytes exposed to oxidative stress had MDA levels of 116.3 ± 14.3 µmol/g Hb. Melatonin (1 µM) slightly increased MDA levels, but 1000 µM melatonin reduced it by 35% (P < 0.05). These findings indicate that melatonin exerts antioxidant effect on lipids. Deterioration of erythrocyte deformability may be due to a separate pro-oxidative action on proteins.

No abstract

The species of Linaria have been used as tonic, antiscorbutic, laxative, antidiabetic, and diuretic, as well as for the treatment of wounds, hemorrhoid and vascular disorders in Turkey. The anti-inflammatory and analgesic effects of different extracts from Linaria grandiflora Desf., L. genistifolia subsp. confertiflora (Boiss.) Davis, L. aucheri Boiss. (Scrophulariaceae) and two isolates (linariin and antirrinoside) from L. aucheri were studied using carrageenan-and PGE 2-induced hind paw edema, 12-O-tetradecanoyl-13-acetate (TPA)-induced ear edema, and p-benzoquinone induced writhing reflex tests in mice. Our findings showed that oral administration of L. aucheri ethyl acetate extract (LA-EtOAc) and L. aucheri 20% aqueous extract, LA-MeOH:H 2 O(8:2), as well as antirrinoside significantly inhibited TPA-induced ear edema in mice. The remaining extracts and linariin did not show any anti-inflammatory activity on carrageenan-, PGE 2-induced hind paw edema, 12-Otetradecanoyl-13-acetate (TPA)-induced ear edema models. Moreover, LA-MeOH:H 2 O (8:2) and antirrinoside displayed significant antinociceptive activity by p-benzoquninone-induced writhing reflex in mice.