Plant-based n-3 polyunsaturated fatty acids (PUFA) possess a prospective antiatherogenic potential. Currant oil from Ribes nigrum L. is one of the few plant oils containing PUFAn-3 (15.3 mol%) in addition to PUFAn-6 (60.5 mol%). This study was aimed at comparing the effects of currant oil with those of lard fat, rich in saturated (43.8 mol%) and monounsaturated (47.0 mol%) fatty acids, on antioxidant parameters, the lipoprotein profile and liver lipids in rats fed on 1 % (w/w) cholesterol diets containing either 10 % of currant oil (COD) or lard fat (LFD). After 3 weeks of feeding, the COD induced a significant decrease in blood glutathione (GSH) and an increase in Cu2+ induced oxidizability of serum lipids, but did not affect liver GSH and t-butyl hydroperoxide-induced lipoperoxidation of liver microsomes. Although the COD did not cause accumulation of liver triacylglycerols as LFD, the lipoprotein profile (VLDL, LDL, HDL) was not significantly improved after COD. The consumption of PUFAn-3 was reflected in LDL as an increase in eicosapentaenoic and docosahexaenoic acid. These results suggest that currant oil affects positively the lipid metabolism in the liver, above all it does not cause the development of a fatty liver. However, adverse effects of currant oil on the antioxidant status in the blood still remain of concern., R. Večeřa, N. Škottová, P. Váňa, L. Kazdová, Z. Chmela, Z. Švagera, D. Walterová, J. Ulrichová, V. Šimánek., and Obsahuje bibliografii
The consequences of increased oxidative stress, measured as the level of malondialdehyde (MDA) during ischemia/reperfusion, were studied in 48 patients in the acute phase of myocardial infarction (AMI) and a control group (21 blood donors). The serum levels of a-tocopherol and b-carotene were followed. Immediately after the treatment onset the level of a-tocopherol started to decrease, reaching a plateau after 24 h. The consumption of b-carotene was delayed by 90 min. Steady decline was detected during the whole time interval studied (48 h). Glutathione peroxidase (GPx) activity, as a representative of antioxidant enzymes, was estimated in whole blood. The influx of oxygenated blood was accompanied by a stimulation of GPx activity, which reached its maximum at the time of completed reperfusion. When comparing the AMI patients with the control group, the levels of MDA were found significantly increased, which indicates that oxidative stress is already increased during ischemia. Lower antioxidant levels found in the patients might either already be the result of vitamin consumption during ischemia or be a manifestation of their susceptibility to AMI. Monitored consumption of a-tocopherol and b-carotene during reperfusion indicated that in the case of patients, whose level of antioxidant vitamins is below the threshold limit, a further substantial decrease of antioxidant vitamins during reperfusion could enhance the oxidative damage of the myocardium., V. Mužáková, R. Kanďár, P. Vojtíšek, J. Skalický, R. Vaňková, A. Čegan, Z. Červinková., and Obsahuje bibliografii
Experimental data on the effect of nicotine on cerebral microvessel thrombosis is lacking. Therefore, this study was carried out to elucidate the effects of nicotine on platelet aggregation in cerebral (pial) microcirculation of the mouse, and the possible protective effect of vitamins C and E. Male TO mice were divided into six groups, and injected i.p. with saline as a control, nicotine (1 mg/kg), vi tamin C alone (100 mg/kg), vitamin E alone (100 mg/kg), nicotine plus vitamin C or nicotine plus vitamin E, all for one week before the experiment. After one week, platelet aggregation in ce rebral microvessels of these groups of mice were studied in vivo . The appearance of the first platelet aggregation and total blood flow stop in arterioles and venules were timed in seconds. In the animals treated with nicotine, venules did not show any alteration in the platelet aggregation time in comparison to the control animals. However, in arterioles platelet aggreg ation time was significantly accelerated (p<0.001) in nicotine-treated animals as compared to controls. Both vitamins C and E prevented the shortening of arteriolar platelet aggregation ti me significantly (p<0.001) when applied with nicotine but not alone. It can be concluded that nicotine enhances the susceptibility to thrombosis in the cerebral arterioles in vivo and that vitamins C and E have alleviating effect on nicotine-induced thrombotic events in mice pial microvessels., M. A. Fahim ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Various reactive oxygen species (ROS) may be produced from normal biochemical, essential metabolic processes or from external sources as exposure to a variety of agents presented in the environment. Lipids, proteins, carbohydrates and DNA are all capable of reacting with ROS and can be implicated in etiology of various human disorders (rheumatoid arthritis, reperfusion injury, atherosclerosis, lung diseases etc.). In the organism damage by ROS is counteracted with natural antioxidants (glutathione peroxidases, superoxide dismutases, catalase, glutathione, ubiquinol, uric acid, and essential minerals) and nutritional antioxidants from diet (i.e. vitamins E, C, carotenoids). Possible mechanisms of nutritional depletion and side effects of high intake are in the article described., Z. Zadák ... [et al.]., and Obsahuje seznam literatury
This study aimed to examine the effect of dietary flavonoid isoquercitrin on ovarian granulosa cells using the immortalized human cell line HGL5. Cell viability, survival, apoptosis, release of steroid hormones 17β-estradiol and progesterone, and human transforming growth factor-β2 (TGF-β2) and TGF-β2 receptor as well as intracellular reactive oxygen species (ROS) generation were investigated after isoquercitrin treatment at the concentration range of 5-100 μg.ml-1 . It did not cause any significant change (p>0.05) in cell viability as studied by AlamarBlue assay in comparison to control. No significant change was observed (p>0.05) in the proportion of live, dead and apoptotic cells as revealed by apoptotic assay using flow cytometry. Similarly, the release of 17β-estradiol, progesterone, TGF-β2 and its receptor were not affected significantly (p>0.05) by isoquercitrin as detected by ELISA, in comparison to control. Except for the highest concentration of 100 μg.ml-1 , which led to oxidative stress, isoquercitrin exhibited antioxidative activity at lower concentration used in the study (5, 10, 25, and 50 μg.ml-1 ) by hampering the production of intracellular ROS, in comparison to control, as detected by chemiluminescence assay (p<0.05). Findings of the present study indicate an existence of the antioxidative pathway that involves inhibition of intracellular ROS generation by isoquercitrin in human ovarian granulosa cells., Adriana Kolesárová, Katarína Michalcová, Shubhadeep Roychoudhury, Simona Baldovská, Eva Tvrdá, Jaromír Vašíček, Peter Chrenek, Ľuboslav Sanisló, Vladimír Křen., and Obsahuje bibliografii
Despite the fact that vessels have sparse cholinergic innervation, acetylcholine (ACh), the primary neurotransmitter of parasympathetic nervous system, has been commonly used in physiological experiments to assess vascular function. ACh is hydrolyzed by two cholinesterases (ChE), namely acetylcholinesterase and butyrylcholinesterase (BChE). However, little is known about these enzymes in blood vessels. The aim of the project was to characterize the expression and activity of ChE in rat aorta. As the effect of ACh on vascular tone depends on the presence of endothelium, Wistar rats were used as a model with intact endothelium and spontaneously hypertensive rats as a model of impaired endothelial function. Relative expressions of both ChE in different parts of the aorta were determined using RT-qPCR. Enzyme activities were assessed in tissue homogenates by Ellman's assay. Here we showed that both ChE are present in each part of rat aorta, while mRNA is more abundant for BChE than for AChE, irrespective of aortic compartment or genotype. Normotensive Wistar rats possess higher aortic mRNA expression and activity of BChE compared to SHR. We concluded that BChE is the dominant type of ChE in rat aorta and it might play an important role in the regulation of vascular tone., Kristína Szmicseková, Lenka Bies Piváčková, Zuzana Kiliánová, Ľubica Slobodová, Peter Křenek, Anna Hrabovská., and Obsahuje bibliografii
High plasma levels of triglycerides (TG) are an independent risk factor in the development of cardiovascular disease, with about 50 % of the final levels being determined genetically. Apolipoprotein A5 ( APOA5 ) is the last discovered member of the apolipoprotein APOA1/C3/A4 gene cluster, found by comparative sequencing analysis. The importance of APOA5 gene for determination of plasma triglyceride levels has been suggested after development of transgenic and knock-out mice (transgenic mice displayed significantly reduced TG, whereas knock-out mice had high TG). In Czech population, alleles C-1131 and Trp19 are associated with elevated levels of plasma TG and higher risk of myocardial infarction development. These alleles also play some role in nutrigenetics and actigenetics of lifestyle interventions leading to the plasma cholesterol changes as well as in the pharmacogenetics of statin treatment. On the contrary, APOA5 mutations detected in Czech population did not show strict effect on plasma TG levels. Val153 → Met variant exhibit the sex-specific effect of HDL-cholesterol levels. The suggested roles of APOA5 variants in determination of the plasma remnant particles, plasma concentrations of C-reactive protein or some anthropometrical parameters were excluded., J. A. Hubáček ... [et al.]., and Obsahuje seznam literatury
Apolipoprotein B (apo B) is the major protein component of LDL, VLDL and chylomicrons. Numerous polymorphisms of the apolipoprotein B gene have been described. Particularly, the insertion/deletion polymorphism located in the coding part of the signal peptide of apo B, associated with modification of lipid concentrations and the risk of cardiovascular disease, has been reported in the general population. No such study in the Tunisian population has been performed. The aim of our study was to assess the effect of insertion/deletion polymorphism of the apolipoprotein B gene on lipid levels in a sample of the Tunisian population. A total of 458 unrelated subjects (321 men and 137 women) were included. The insertion/deletion polymorphism was determined by electrophoresis on polyacrylamide gels after PCR amplification. The relative frequencies of the Ins and Del alleles were 0.74 and 0.26, respectively. These frequencies were similar to those found in other Caucasian populations. There was no significant difference in serum TC, TG, and HDL-C levels due to the influence of the genotypes. However, significant variation among the three genotypes was seen for LDL-cholesterol (p<0.001) and apo B (p<0.001) levels. Individuals homozygous for the Del allele had higher levels than individuals homozygous for the Ins allele, while individuals heterozygous for both alleles exhibited intermediate levels. When the data were analyzed in men and women separately, a similar effect was seen in both groups. Our results show that distribution of apo B insertion/deletion polymorphism in Tunisians is similar to other Caucasian population and confirm the reported association with serum LDL-cholesterol and apo B concentrations., A. Kallel, M. Fekl, M. Elasmi, M. Souissi, H. Shanhaji, S. Omar, S. Haj Taieb, R. Jemaa, N. Kaabachi., and Obsahuje bibliografii a bibliografické odkazy
Apolipoproteins E and CI are the predominant components of triglyceride-rich lipoproteins. The genes are located in one gene cluster and both are polymorphic. Three allelic (ε2, ε3 and ε4) polymorphisms of the APOE gene influence plasma cholesterol levels. The distribution of these alleles differ between ethnic groups. PCR genotyping was used to determine the APOE and APOCI allele incidence in a representative group of 653 probands (302 men and 351 women) of Czech origin. The observed relative frequencies for the ε2, ε3 and ε4 alleles were 7.1 %, 82.0 % and 10.9 %, respectively, and are similar to other middle European populations. APO ε4 carriers have the highest and APO ε2 carriers the lowest levels of plasma total cholesterol (p<0.0001) and LDL cholesterol (p<0.0001). The frequency of the insertion (I) allele (HpaI restriction site present) of the APOCI polymorphism was 18.5 %. APOCI I/I homozygotes have the highest level of triglycerides (p<0.003). An almost complete linkage disequilibrium of the insertion allele of APOCI with the APOE alleles ε2 and ε4 has been detected and suggests that the deletion in the APOCI gene probably follows the deriving of all three APOE alleles on the APO ε3 allele background., J. A. Hubáček, J. Piťha, V. Adámková, Z. Škodová, V. Lánská, R. Poledne., and Obsahuje bibliografii