Serum paraoxonase 1 activity is associated with fatty acid composition of high density lipoprotein.

INTRODUCTION: Cardioprotective effect of high density lipoprotein (HDL) is, in part, dependent on its related enzyme, paraoxonase 1 (PON1). Fatty acid composition of HDL could affect its size and structure. On the other hand, PON1 activity is directly related to the structure of HDL. This study was designed to investigate the association between serum PON1 activity and fatty acid composition of HDL in healthy men. METHODS: One hundred and forty healthy men participated in this research. HDL was separated by sequential ultracentrifugation, and its fatty acid composition was analyzed by gas chromatography. PON1 activity was measured spectrophotometrically using paraxon as substrate. RESULTS: Serum PON1 activity was directly correlated with the amount of stearic acid and dihomo-gamma-linolenic acid (DGLA). PON1/HDL-C was directly correlated with the amount of miristic acid, stearic acid, and DGLA and was inversely correlated with total amount of ω 6 fatty acids of HDL. CONCLUSION: The fatty acid composition of HDL could affect the activity of its associated enzyme, PON1. As dietary fats are the major determinants of serum lipids and lipoprotein composition, consuming some special dietary fatty acids may improve the activity of PON1 and thereby have beneficial effects on health.

The associations between high-density lipoprotein mean particle size and its fatty acid composition.

AIM: High-density lipoprotein (HDL) particles are heterogeneous in their composition, structure and size and may differ in conferring protection against coronary artery disease. The aim of this study is to investigate the associations between HDL size and its fatty acid composition. PATIENTS & METHODS: HDL mean particle size from 140 healthy men was detected by dynamic light scattering methodology and fatty acid composition of HDL was determined by gas chromatography. RESULTS: HDL with smaller size had a higher proportion of saturated fatty acids and lower proportion of unsaturated fatty acids. HDL mean size indicated a negative correlation with palmitic acid (r = -0.17; p < 0.05) and a positive correlation with palmitoleic acid (r = 0.17; p < 0.05), oleic acid (r = 0.23; p < 0.01), arachidonic acid (r = 0.17; p < 0.05) and dihomogamalinoleic acid (r = -0.18; p < 0.05). CONCLUSION: Saturated fatty acids of HDL are inversely assocaited and unsaturated fatty acids are directly associated with HDL mean size.

Evaluation of the effects of weak and moderate static magnetic fields on the characteristics of human low density lipoprotein in vitro.

It has been suggested that exposure to electromagnetic fields may be a risk factor for cardiovascular disease in humans. Low density lipoprotein (LDL) modifications such as peroxidation and aggregation have been implicated in the pathogenesis of atherosclerosis. The present study investigated the effects of weak (0.125-0.5 mT) and moderate (1-4 mT) static magnetic fields (SMFs) on LDL oxidation, aggregation and zeta potential in vitro. Our results demonstrated that magnetic flux densities of 0.25 and 0.5 mT decreased, and magnetic flux densities of 3 and 4 mT increased the zeta potential and LDL oxidation in comparison with the control samples. All doses of SMFs increased the LDL aggregation in a time- and dose-dependent manner. It is concluded that SMFs can alter the susceptibility of LDL to oxidation and this alteration is dependent on the applied magnetic flux density. The SMF, in addition to its role in the production and stabilization of free radicals and promotion of lipid peroxidation, may influence the metabolism of lipoproteins and their interaction with other molecules such as apolipoproteins, enzymes and receptors through the alteration of the LDL zeta potential and its particles tendency to aggregation.

Chemical analysis and biological activities of Cupressus sempervirens var. horizontalis essential oils.

CONTEXT: Safe and effective antioxidants are regarded as a cornerstone for the prevention and treatment of several types of disorders. OBJECTIVE: The present study aimed to investigate the antioxidant and anti-glycation properties of branchlet and fruit oils of Cupressus sempervirens L. var. horizontalis (Mill.) Gord. (Cupressaceae). MATERIALS AND METHODS: Essential oils were extracted from the branchlets and fruits of C. sempervirens var. horizontalis using the steam distillation method. A gas chromatography-mass spectrometry method was employed for the compositional analysis of essential oils. In order to evaluate antioxidant activities of oils at different concentrations (180, 220 and 260 µg mL(-1)), linoleic acid peroxidation test and peroxyl radical mediated hemolysis of red blood cells (RBC) assay were used. Linoleic acid peroxidation was monitored for 4 h and determined during each hour of incubation. Antiglycation effects of oils at 200, 400 and 600 µg mL(-1) were assessed using hemoglobin and insulin glycation assays. RESULTS: Overall, 10 volatile components were identified, amounting for 88.2 and 93.2% of branchlet and fruit oils, respectively. α-Pinene and δ-3-carene were major components of both branchlet (46.2 and 22.7%) and fruit (59.2 and 14.9%) oils. Hemoglobin glycation was inhibited by both branchlet (44.8, 62.6 and 54.0% at 200, 400 and 600 µg mL(-1), respectively) and fruit (41.0, 62.8 and 48.5%) oils. As for the insulin glycation, inhibitory rates were 66.1, 69.2 and 73.8% for branchlet oil, and 80.0, 76.9 and 81.5% for fruit oil (at 200, 400 and 600 µg mL(-1), respectively). RBC hemolysis was also inhibited by both branchlet (49.9, 38.5 and 15.0% at 180, 220 and 260 µg mL(-1), respectively) and fruit (45.9, 38.6 and 25.0%) oil. Finally, the oils mitigated linoleic acid peroxidation which was peaked after 4 h for both branchlet (39.5, 35.6 and 53.4% at 180, 220 and 260 µg mL(-1), respectively) and fruit (47.5, 58.6 and 59.8%) oil. CONCLUSIONS: The present findings suggest that essential oils obtained from the branchlets and fruits of C. sempervirens var. horizontalis possess antioxidant and, in particular, antiglycation properties. These activities may find implication in the prevention of diabetic and cardiovascular complications. However, further investigations are required to justify the traditional medical applications of the plant.

Associations between high density lipoprotein mean particle size and serum paraoxonase-1 activity.

BACKGROUND: High density lipoprotein (HDL) particles are heterogeneous in composition, structure, size, and may differ in conferring protection against cardiovascular disease. HDL associated enzyme, paraoxonase-1 (PON1), has an important role in attenuation of atherogenic low density lipoprotein (LDL) oxidation. The aim of this study was to investigate the associations between HDL particle size and PON1 activity in relation to serum HDL cholesterol (HDL-C) levels. MATERIALS AND METHODS: One hundred and forty healthy subjects contributed to this study. HDL was separated by sequential ultracentrifugation and its size was estimated by dynamic light scattering. Paraoxonase activity was measured spectrophotometrically using paraoxon as substrate. RESULTS: Results of this study showed that PON1 activity had negative correlations with HDL mean particle size (r = -0.22, P < 01), HDL2/HDL3 ratio, and serum HDL-C levels (r = -0.25, P < 0.01). HDL mean particle size and HDL2/HDL3 ratio had negative correlation with body mass index (BMI), waist hip ratio (WHR), and serum triglyceride (TG) levels, and positive correlation with serum HDL-C levels. Serum HDL-C levels had significant positive correlations with age, total cholesterol (TC), and apolipoprotein A-I (apo A-I) and significant negative correlation with BMI, WHR, and TG. CONCLUSION: Based on the results of this study, determination of HDL mean particle size beside the serum PON1 activity may help to better understand the CAD risks, pathogenesis, and prognosis, and may also help to design therapeutic protocols toward beneficial modifications of HDL characteristics.

Validity and reproducibility of a food frequency questionnaire for assessment of fruit and vegetable intake in Iranian adults(*).

BACKGROUND: This study's aim was to design and validate a semi-quantitative food frequency questionnaire (FFQ) for assessment of fruits and vegetables (FV) consumption in adults of Isfahan by comparing the FFQ with dietary reference method and blood plasma levels of beta-carotene, vitamin C, and retinol. METHODS: This validation study was performed on 123 healthy adults of Isfahan. FV intake was assessed using a 110-item FFQ. Data collection was performed during two different time periods to control for seasonal effects, fall/winter (cold season) and spring/summer (warm season). In each phase a FFQ and 1 day recall, and 2 days of food records as the dietary reference method were completed and plasma vitamin C, beta-carotene and retinol were measured. Data was analyzed by Pearson or Spearman and intraclass correlations. RESULTS: Serum Lipids, sex, age, body mass index (BMI) and educational level adjusted Pearson correlation coefficient of FV with plasma vitamin C, beta-carotene and retinol were 0.55, 0.47 and 0.28 in the cold season (p < 0.05) and 0.52, 0.45 and 0.35 in the warm season (p < 0.001), respectively. Energy and fat intake, sex, age, BMI and educational level adjusted Pearson correlation coefficient for FV with dietary reference method in the cold and warm seasons were 0.62 and 0.60, respectively (p < 0.001). Intraclass correlation for reproducibility of FFQ in FV was 0.65 (p<0.001). CONCLUSIONS: The designed FFQ had a good criterion validity and reproducibility for assessment of FV intake. Thus, it can serve as a valid tool in epidemiological studies to assess fruit and vegetable intake.

Effect of hydrogenated, liquid and ghee oils on serum lipids profile.

BACKGROUND: Trans fatty acids are known as the most harmful type of dietary fats, so this study was done to compare the effects of hydrogenated, liquid and ghee oils on serum lipids profile of healthy adults. METHODS: This study was a randomized clinical trial conducted on 129 healthy participants aged from 20 to 60 years old who were beneficiaries of Imam-e-Zaman charitable organization. Subjects were randomly divided into 3 groups and each group was treated with a diet containing cooking and frying liquid, ghee, or hydrogenated for 40 days. Fasting serum lipids, including total cholesterol (TC), triglyceride (TG), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), apoprotein A (Apo A), and apoprotein B (Apo B) were measured before and after the study. RESULTS: TC, TG and Apo B had a significant reduction in the liquid oil group compared to the hydrogenated oil group. In the ghee group TG declined and Apo A increased significantly (P < 0.01). Liquid oil group had a significant reduction in HDL-C, compared to the ghee oil group (P < 0.05). CONCLUSION: It was concluded that consuming liquid oil along with frying oil caused to reduce all serum lipid levels. However, ghee oil only reduced TG and increased HDL-C levels.

Effect of opium addiction on new and traditional cardiovascular risk factors: do duration of addiction and route of administration matter?

BACKGROUND: There is a belief among some society that opium has a number of beneficial effects on cardiovascular disease. The aim of the present investigation as a cross-sectional study was to assess this hypothesis. Several biochemical factors (Fasting blood sugar, Cholesterol, Triglyceride, LDL-Cholesterol, HDL-Cholesterol, HbA1C, CRP, Fibrinogen, Factor VII, SGOT, SGPT, Lpa, apo A and apo B were evaluated in opium-addicted men (case) against non opium-addicted men(control). Three hundred and sixty opium-addicted men were divided into three groups according to the route of administration (Orally, Vafour and Sikh-Sang) and each group was divided into four subgroups according to the duration of addiction (5 months, 1 year, 2 years and 5 years). Blood morphine concentration was measured by ELISA method. RESULTS: The results show that morphine concentration was significantly higher in orally administration. In all routes, there was a direct correlation between blood morphine concentration and period of addiction. Regardless to the period and route of administration, the level of HbA1C, CRP, factor VII, Fibrinogen, apo B, Lpa, SGOT, and SGPT were significantly higher in the case subjects as compared with controls and HDL-Cholesterol and apo a were significantly lower in the case subjects. CONCLUSION: This study demonstrated the deleterious effects of opium on some traditional and new cardiovascular disease risk factors. These deleterious effects are related to the period of addiction and their levels are significantly increased after 2 years of addiction. Route of administration impresses cardiovascular risk factors and "Sikh-Sang" showed the worst effect.

Fibrinolytic effects of Ginkgo biloba extract.

A multitude of factors are involved in regulating the blood coagulation homeostatic processes in the body, which may ultimately lead to thromboemboli and thrombosis. The resolution of blood clots after healing is as important as clot formation at the site of a vascular lesion. This is accomplished by fibrinolytic drugs such as streptokinase (SK) and urokinase.It must be noted that administration of SK may be accompanied by the lysis of blood clots in unwanted sites, and complications such as general lytic conditions, severe hemorrhaging, reduced serum fibrinogen and allergies can occur. Anti-SK antibodies neutralize the effects of SK. Studies on natural compounds and medicinal herbs with fewer side effects have been ongoing. In the present study, the fibrinolytic effect of Ginkgo biloba, an herb grown in Iran, was investigated.A polyphenolic method was used to obtain Ginkgo extract from its leaves. The fibrinolytic effects of SK (positive control) were compared with those of Ginkgo extract using a fluorometry method.In producing a labelled clot, fibrinogen was labelled with the fluorescent agent fluorescein isothiocyanate and precipitated in the presence of Ca(2+). SK (100 U/mL to 1000 U/mL) and Ginkgo extract were added to labelled fibrin in a plasma environment at dilutions of 1, 1:10, 1:100 and 1:1000 (volume/volume). The fluorescence of the solution was measured between 15 min and 60 min later.A linear relationship was observed between the fluorescence measured and SK concentrations ranging from 300 U/mL to 700 U/mL. Ginkgo extract displayed a remarkable effect in resolving the clot. As Ginkgo extract remained in the environment, fluorescence increased notably, showing a time-dependent relationship.Overall, the results indicate that the effects of Ginkgo extract on the fibrinolytic system are similar to those of SK; hence, this herbal extract can be used as a complement to or a substitute for SK. Additionally, it is proposed that the effects of the active ingredients of Ginkgo extract should be studied in animals. Further studies are warranted for evaluating the possible side effects and toxicity of Ginkgo extract in human subjects.

Immunosuppressive activity of a molecule isolated from Artemisia annua on DTH responses compared with cyclosporin A.

Artemisia belongs to the family of Compositea; there are different Artemisias in Iran, of which Artemisia annua L. is grown in the north of Iran. In this study, Artemisinin was extracted and purified from the whole plants. The purification of Artemisinin was performed using column chromatography in different polarities of solvents and the results were evaluated by Thin Layer Chromatography (TLC). (1)H-NMR (NMR-500) spectroscopy was used to characterize the purified Artemisinin. The immunosuppressive activity of Artemisinin was investigated on Balb/c mice by DTH response in comparison to cyclosporin A (CsA). The data indicated that Artemisinin could suppress the delayed type hypersensitivity (DTH) against sheep blood capsule in Balb/c mice. Also its inhibitory effect on calmodulin (CaM) structure was determined by fluorescence spectroscopy. The data indicated an inhibitory effect of that on the activity of calmodulin by increasing the fluorescence emission of calmodulin. Both in vivo (DTH response) and in vitro (spectrofluorometry) studies indicated the activity of Artemisinin as an immunosuppressive agent and that the fluorescence emission of calmodulin is more than cyclosporin A.

Antioxidant activity of three extracts of Morus nigra.

The antioxidant effect of three different extracts of Morus nigra fruit (fruit juice, hydroalcoholic and polyphenolic) on haemoglobin glycosylation, peroxidative damage to human erythrocytes, liver hepatooytes of rats and human low-density lipoprotein (LDL) were studied. The results show that all three extracts inhibited haemoglobin glycosylation induced by glucose to differing degrees. The haemolysis of human erythrocytes induced by hydrogen peroxide was also inhibited. The production of malondialdehyde (MDA) during peroxidative damage to plasma membranes of isolated rat hepatocytes induced by tert-butyl hydroperoxide (tBH) was also inhibited. Inhibition of lipid peroxidation of LDL induced by copper (II) ion was achieved during the study. The results suggest that Morus nigra fruit has a protective action against peroxidative damage to biomembranes and biomolecules.

Tobacco use among Iranian men, women and adolescents.

The aim of this study was to evaluate the self-reported and serum cotinine based prevalence rates of smoking among Iranian men, women and adolescents. The study was carried out on 2626 men and women aged 19 years and above and 836 high school students aged 14-18 years, randomly selected from different clusters and schools in Isfahan. The WHO smoking standard questionnaire was completed for all samples and serum cotinine level was measured using high-performance liquid chromatography in 10% and 20% of the original adult and adolescent samples, respectively. The prevalence of self-reported smoking among Iranian men and women aged 19 years and above was 18.7% and 1.3%, respectively, compared to 21.2% and 6.7% based on serum cotinine level. Nearly 10.6% and 14.6% of claimed nonsmoker girls and boys were classified as current smokers by serum cotinine level. More than 80% of male smokers started the habit before the age of 20 years and the effect of smoker friends was the most important factor for smoking initiation among smokers. Using self-reported prevalence data for smoking among women or adolescents in special populations like Iranians can give invalid measurements, therefore, data based on biochemical tests are suggested.

Effect of some volatile oils on the affinity of intact and oxidized low-density lipoproteins for adrenal cell surface receptors.

Extensive research has shown that a high plasma concentration and oxidation of low-density lipoproteins (LDL) has an important role in atherogenesis. The affinity of LDL to its classic receptor is reduced due to oxidation. Instead, it is taken up by scavenger molecules in macrophages, as a result of which foam cells are formed that have a major role in increasing the subendothelial fat layers of the blood vessels. In the present study the antioxidant effect of eight volatile compounds in plant essences, namely, anethol, eugenol, limonen, linalool, p-cymol, pulegon, thymol, and geraniol, and their effect on the affinities of intact and oxidized (with Cu(+2)) LDL for LDL receptor in sheep adrenal tissue cells in the presence of labeled LDL with fluorescein isothiocynate (FITC) were investigated. The results obtained show that eugenol and thymol have the highest antioxidant effect, on the uptake of LDL (intact and oxidized) by the adrenal cells. The order of the compounds studied with regard to their antioxidant effect on intact and oxidized LDL is as follows: On intact LDL: eugenol > or = thymol > linalool > p-cymol > limonen > geraniol > anethol; on oxidized LDL: thymol > or = eugenol > geraniol > p-cymol > linalool > pulegon. Our findings also show that the compounds, particularly thymol and eugenol, have an antioxidant property and can change the affinity of the LDL particles for the LDL receptor probably due to their lipophylic property. Further research may prove that these compounds can be used clinically, especially in atherosclerotic and hypercholesterolemic cases.

Anti-oxidant effect of flavonoids on the susceptibility of LDL oxidation.

In vitro studies have demonstrated increased atherogenicity of oxidized low-density lipoprotein (ox-LDL) compared to native LDL. Oxidative modification of LDL alters its structure allowing LDL to be taken up by scavenger receptors on macrophage, endothelial, and smooth muscle cells, leading to the formation of lipid-laden foam cells, the hallmark of early atherosclerotic lesions. The susceptibility of LDL to in vitro oxidation was assessed essentially by the technique described by Esterbauer et al. LDL oxidation were monitored by change in 234-absorbance in the presence and absence of pure flavonoids. Morin, genistein, apigenin and biochanin A, naringin and quercetin were used at different concentration. These flavonoids significantly inhibit in vitro LDL oxidation, genistein, morin and naringin have stronger inhibitory activity against LDL oxidation than biochanin A or apigenin. This study show that flavonoids prevent in vitro LDL oxidation and probably would be important to prevent atherosclerosis.

Atherosclerosis risk factors in children and adolescents with or without family history of premature coronary artery disease.

BACKGROUND: Although coronary artery disease (CAD) becomes symptomatic much later in life, the early identification and modification of risk factors may reduce its later incidence. MATERIAL/METHODS: 100 subjects 2-18 years old, evenly divided by sex, were randomly selected from among children of patients suffering from premature myocardial infarction (<55 years); the controls were 100 age- and sex-matched subjects without a similar family history. In the Pediatric Preventive Cardiology Clinic at the Isfahan Cardiovascular Research Center, the subjects completed a special questionnaire consisting of anthropometric data, blood pressure, skinfold thickness, rate of physical activity, and active or passive cigarette smoking. Fasting venous blood was analyzed for serum lipids, lipoproteins fibrinogen, and apolipoproteins A1 and B100. The data were analyzed with SPSS V6/win using the independent t-test, Kruskal-Wallis, chi-squared, and standard linear multiple regression tests. RESULTS: The data showed higher prevalence of some major and new risk factors in the experimental group than in the controls. The mean total cholesterol, LDL-C, TG, fibrinogen and Apo B100 were significantly higher in the experimental group, while the mean values of HDL-C and Apo A1 were significantly lower. The differences in terms of Body Mass Index, percentage body fat, rate of regular physical activity, and active and passive smoking were not significant between groups. CONCLUSIONS: Major and new CAD risk factors should be identified and modified as early as possible in children with high family risk by screening and health education at an early age.

The inhibitory effects of pure flavonoids on in vitro protein glycosylation.

Non-enzymatic glycosylation of proteins is the major cause of diabetic complications, such as cardiovascular disorders, retinopathy, nephropathy and neuropathy. It seems that protein glycosylation can be inhibited effectively by antioxidants. Several flavonoids, such as rutin, kaempferol, quercetin, apigenin, naringin, morin and biochanin A were selected to determine their antioxidant effects on in vitro insulin, hemoglobin and albumin glycosylation. The optimal glucose concentration and incubation time were obtained for each protein. Then, the inhibition percentage of protein glycosylation was measured in the presence of three different concentrations (0.5, 5, 10 microg/ml) of each flavonoids by a colorimetric method. The results demonstrated that biochanin A, the best inhibitor of insulin and hemoglobin glycosylation, inhibits their glycosylation 100% and 60%, respectively. Glycosylation of albumin was inhibited 100% by both biochanin A and apigenin. Therefore, it seems probable that plants containing flavonoids may have preventive effects in diabetic complications.