Hypocholesterolemic and antiatherosclerotic effect of artemisia aucheri in hypercholesterolemic rabbits.

Atherosclerosis which results from gradual deposition of lipids in arteries is a leading cause of mortality worldwide. Diet is one of the most important factors underlying atherosclerosis. High-cholesterol diets enhance atherosclerosis and vegetarian diets are known to slow down the process. Artemisia aucheri is an herb of the Composite family. Many species of Artemisia have proven hypolipidemic and antioxidant properties. This study determine the effects of Artemisia aucheri on lipoproteins and atherosclerosis in hypercholesterolemic rabbits. Fifteen male rabbits were randomly divided into three groups. Normal diet group, high-cholesterol diet group (1% cholesterol) and Artemisia aucheri group (1% cholesterol diet supplemented with 100 mg/kg body weight the Artemisi aucheri every other day). Biochemical factors were measured at the start, end of the first and second months of the study. At the end of the study, the aorta were removed for assessment of atherosclerotic plaques. The results indicate that Artemisia aucheri significantly reduced the level of total cholesterol, LDL cholesterol and triglycerids and increased HDL cholesterol. The degree of atherosclerotic thickness was significantly reduced in the treated group. Therefore, Artemisia aucheri is one of the useful herbal medicine for preventation of atherosclerosis and more studies in this regard is recommended.

Protective effect of flavonoids against red blood cell hemolysis by free radicals.

BACKGROUND: Flavonoids are polyphenolic substances with antioxidant properties, and they are found in different vegetables and fruits. Epidemiological studies have shown that the consumption of flavonoids reduces the prevalence of cardiovascular diseases. The use of synthetic antioxidants, however, has been limited because of their toxicity. Therefore, medical researchers have intensified their quest to find natural antioxidants. OBJECTIVES: To investigate the effect of several pure flavonoids, such as kaempferol, quercetin, morin and rutin, on red blood cell hemolysis and evaluate their -SH capacity as an indicator of membrane protection. METHODS: The rate of hemolysis and cell membrane -SH capacity were determined by spectrophotometry. Red blood cell peroxidation was induced using 2,2'-azo-bis-(2-amidinopropane) dihydrochloride. The effect of each flavonoid on hemolysis was examined at three concentrations (0.5 mug/mL, 5 mug/mL and 10 mug/mL), however, only the greatest concentration (10 mug/mL) of each flavonoid was used to study the effect on -SH groups. RESULTS: In all cases, the antioxidant activity was dose-dependent. Rutin showed the highest inhibitory effect on hemolysis among flavonoids (42.5%). The protective effect of kaempferol, rutin and morin against -SH group oxidation measured 7.7%, 23.3% and 26.4%, respectively. CONCLUSIONS: Results showed that flavonoids and flavonoid-containing plants can be used as natural antioxidants for the treatment and prevention of disease conditions, the pathogenesis of which is mediated by lipid peroxidation.

Effects of cigarette smoke, nicotine and cotinine on red blood cell hemolysis and their -SH capacity.

BACKGROUND: Smoking is a leading cause of premature death. Red blood cell (RBC) membrane lipids are rich in polyunsaturated fatty acids; therefore, the effect of oxygen on RBC membranes is more prominent than on other body tissues. The attachment of peroxidants to RBC membranes can result in hemolysis. OBJECTIVES: The present study was conducted to assess the sensitivity of RBCs to 2,2'-azo-bis-(2-amidinopropane) dihydrochloride in smokers and nonsmokers. The effect of cigarette smoke, nicotine (1 mug/mL, 1.5 mug/mL and 2.5 mug/mL) and cotinine (1.25 mug/mL, 2.5 mug/mL and 5 mug/mL) on RBC hemolysis was also examined. RESULTS: RBC hemolysis in smokers was 21.6% higher than in non-smokers (P<0.05). Cigarette smoke increased 2,2'-azo-bis-(2-amidino-propane) dihydrochloride-induced RBC hemolysis by 281.7%. Nicotine inhibited RBC hemolysis by 36.7% at the highest concentration used, but increased RBC hemolysis at the lower concentrations. Cotinine caused a 13.8% increase in RBC membrane peroxidation at the highest concentration used and its effects were dose-dependent. At their highest concentrations, nicotine and cotinine decreased -SH groups by 50%. CONCLUSIONS: The present study confirms the results from previous studies of the oxidative and destructive effects of cigarette smoke, which are detrimental to the health of both active and passive smokers.

Effect of Amirkabiria odorastissima mozaffarian on the development and progression of fatty streaks in hypercholesterolemic rabbits.

New studies have introduced atherosclerosis as an inflammatory disease. Different factors affect the development of inflammation that can be linked to free radicals, hypertention, diabetes mellitus, genetic changes, hypercholesterolemia and some of the microorganisms. Using anti-inflammatory drugs can be useful in preventing atherosclerosis. Finding drugs from natural sources and without side-effects can be useful. Amirkabiria odoratissima (umbelliferae) is from Iranian fl ora and is used traditionally as an anti-inflammatory drug. This study was designed to assess the effects of this plant on the development and progression of fatty streaks. Male rabbits were fed: (a) rabbit chow; (b) 1% cholesterol diet; (c) cholesterol diet supplemented with the plant; (d) normal diet supplemented with the plant. After 12 weeks, the animals were sacrificed and the aorta, right and left branches of coronary arteries were dissected and histologically processed. Before and after the end of the study, biochemical factors were measured. The amounts of cholesterol, LDL, HDL, triglyceride and fasting blood sugar (FBS) were determined by enzymatic methods, quantitative CRP was determined by turbidimetric methods, malondialdehyde (MDA) and antioxidant capacity were determined by speceterophotometric methods. The results indicate that there is a significant difference between the groups supplemented with herbal medicine and others (p < 0.05) in the mean grade of fatty streak of right and left coronary artery and aorta. At the end of the 12-week period cholesterol, LDL and CRP were significantly reduced in the groups which received herbal medicine (p < 0.05). The data suggests that Amirkabiria odoratissima Mozaffarian has beneficial effects to prevent development of fatty streak; however, further studies are needed to understand the mechanisms whereby this plant exerts its anti-atherosclerotic effects.