Browsing by Author "Devrim, E"

Now showing 1 - 2 of 2

Effects of Cholesterol Supplementation on Antioxidant Enzyme Activities in Rat Hepatic Tissues
(Elsevier Sci Ltd, 2004) Durak, I; Özbek, H; Devrim, E; Karagenç, N; Ergüder, IB
Background and Aim: The effects of cholesterol supplementation on antioxidant enzyme activities were investigated in hepatic tissue taken from Sprague Dawley rats. Methods and Reults: The study involved 14 male Sprague Dawley rats: seven fed a normal laboratory diet and seven a normal diet plus cholesterol (3.6 g/kg/day) for three months, during which blood samples were obtained to measure serum cholesterol levels. At the end of the 3-month period, the livers were surgically removed in order to measure antioxidant enzyme activities (superoxide dismutase, catalase, glutathione peroxidase and paraoxonase-1). At the end of the study period, serum total cholesterol and HDL-cholesterol levels were significantly higher in the cholesterol-fed group than the control group. There were no significant between-group differences in hepatic superoxide dismutase, catalase and glutathione peroxidase activities, but there was a significant decrease in hepatic paraoxonase-1 activity in the cholesterol-fed group. Conclusions: Cholesterol supplementation significantly decreases paraoxonase-1 activity in rat liver tissue without changing the activities of other antioxidant enzymes. These results suggest that cholesterol significantly suppresses hepatic paraoxonase-1 synthesis. It seems that the decreased paraoxonase-1 activity in the plasma HDL-fraction of atherosclerotic patients is associated with suppressed liver synthesis. A reduction in paraoxonase-1 activity may therefore lead to the more intensive exposure of LDL to oxidant attacks. Nutr Metab Cardiovasc Dis ((C)) 2004, Medikal.
Effects of Garlic Extract Consumption on Blood Lipid and Oxidant/Antioxidant Parameters in Humans With High Blood Cholesterol
(Elsevier Science inc, 2004) Durak, I; Kavutcu, M; Aytaç, B; Avci, A; Devrim, E; Özbek, H; Öztürk, HS
Effects of garlic extract supplementation on blood lipid profile and oxidant/antioxidant status were investigated in volunteer subjects with high blood cholesterol. A total of 23 volunteer subjects with high blood cholesterol (>5.98 mmol/L) participated in the study. Of them, 13 patients were evaluated as a hypertensive group and the others a normotensive group. Before (first sample) and after (second sample) garlic extract consumption for 4 months, routine blood analyses including lipid parameters and liver and kidney function tests were performed. Additionally, blood oxidant (malondialdehyde [MDA], oxidation resistance [OR]), and antioxidant (antioxidant potential [AOP], nonenzymatic superoxide radical scavenger activity [NSSA]) parameters were measured. Serum total cholesterol, low-density lipoprotein (LDL) and very-low-density lipoprotein (VLDL) cholesterols, and triglyceride levels were found to be significantly lowered, but HDL high-density lipoprotein cholesterol level increased after the extract use. The total:HDL cholesterol ratio was also found to be significantly decreased after the extract use. There were no meaningful differences with regard to other routine biochemical parameters. Additionally, blood AOP, OR, and NSSA values were found increased and MDA level decreased in the second samples relative to the first ones. Systolic and diastolic blood pressure values were also found to be significantly lowered after extract supplementation in the hypertensive group, but no similar changes were observed in the normotensive group. We conclude that garlic extract supplementation improves blood lipid profile, strengthens blood antioxidant potential, and causes significant reductions in systolic and diastolic blood pressures. It also leads to a decrease in the level of oxidation product (MDA) in the blood samples, which demonstrates reduced oxidation reactions in the body. (C) 2004 Elsevier Inc. All rights reserved.