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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 α-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.

Background: The purpose of the present study was to investigate the effects of vitamin E on oxidative stress and cell membrane fluidity in the liver of streptozotocin (STZ)-induced diabetic rats. Methods: Sprague-Dawley male rats weighing 100 ± 10 g were fed a vitamin E-free diet (the DM-0E group), a 40 mg vitamin E/kg diet (the DM-40E group), or a 400 mg vitamin E/kg diet (the DM-400E group). Result: Dietary vitamin E reduced the increased concentration of lipid peroxides in the liver tissues of diabetic rats through decreasing their increased phospholipase A2 (PLA2) activity and phosphatidylethanolamine hydrolysis. However, vitamin E reduced the accumulation of superoxide radical and decreased the generation of oxidative damage substances, such as the carbonyl value, increased membrane fluidity and lowered oxidative damage. Conclusions: Vitamin E was found to be excellent for regulating the activity of PLA2, reducing the generation of reactive oxygen species and damaging oxidative substances, and maintaining cell membrane fluidity in the liver of diabetic rats.

The purpose of this study was to investigate the effects of green tea catechin on polymorphonuclear leukocyte 5′-lipoxygenase activity, leukotriene B4 synthesis, and renal damage in diabetic rats. Male Sprague-Dawley rats weighing 100 ± 10 g were randomly assigned to 1 normal group and 3 diabetic groups given a catechin-free diet (DM-0C group), 0.25% catechin diet (DM-0.25C group), or 0.5% catechin diet (DM-0.5C group), respectively. 5′-Lipoxygenase activity in the polymorphonuclear leukocytes significantly increased by 54% in the DM-0C group compared to the normal group, while the level in the DM-0.5C group remained the same as in the normal group. The leukotriene B4 content in the polymorphonuclear leukocytes increased 55% in the DM-0C group compared to the normal group, whereas the DM-0.25C and DM-0.5C groups exhibited the same level as the normal group. The superoxide radical content in the kidney microsomes increased 116% in the DM-0C group when compared to the normal group, yet decreased 29% in the DM-0.25C group and 50% in the DM-0.5C group compared to DM-0C group. The lipofuscin content was 197 and 136% higher in the DM-0C and DM-025C groups, respectively, than in the normal group, whereas the DM-0.5C group exhibited the same content as in the normal group. The carbonyl value increased 118% in the DM-0C group compared to the normal group, and the DM-0.25C and DM-0.5C groups were not significantly different from the DM-0C group. Accordingly, these results indicate that dietary catechin inhibited the generation of superoxide radicals, oxidized protein, and lipid peroxide in the kidney of streptozotocin-induced diabetic rats. Furthermore, green tea catechin supplementation in diabetic rats also appeared to inhibit the production of leukotriene B4 based on regulating the activity of 5′-lipoxygenase, thereby potentially reducing renal oxidative damage and inflammatory reactions.