Search

Start Over Creator Kovář, J.

12. The A-204C Polymorphism in the Cholesterol 7α-hydroxylase (CYP7A1) Gene Determines the Cholesterolemia Responsiveness to a High-Fat Diet

Creator:
Kovář, J., Suchánek, P., Hubáček, J.A., and Poledne, R.
Type:
article, model:article, and TEXT
Subject:
LDL-cholesterol, Cholesterol 7 alfa-hydroxylase, Diet responsiveness, and Genetics
Language:
English
Description:
The aim of the study was to ascertain whether the A-204C polymorphism in the cholesterol 7alfa-hydroxylase (CYP7A1) gene plays any role in determining LDL-cholesterol (LDL-C) concentration responsiveness to a high-fat diet. The concentrations of total cholesterol and LDL-cholesterol were measured in eleven healthy men (age: 30.9±3.2 years; BMI: 24.9±2.7 kg/m2) who were homozygous for either the -204A or -204C allele, after 3 weeks on a low-fat (LF) diet and 3 weeks on a high-fat (HF) diet. During both dietary regimens, the isocaloric amount of food was provided to volunteers; LF diet contained 22 % of energy as a fat and 2.2 mg of cholesterol/kg of body weight a day, HF diet 40 % of fat and 9.7 mg of cholesterol/kg of body weight a day. In six subjects homozygous for the -204C allele, the concentrations of cholesterol and LDL-cholesterol were significantly higher on HF than on LF diet (cholesterol: 4.62 vs. 4.00 mmol/l, p<0.05; LDL-C: 2.15 vs. 1.63 mmol/l, p<0.01, respectively); no significant change was observed in five subjects homozygous for the -204A allele. There were no other differences in lipid and lipoprotein-lipid concentrations. Therefore, the polymorphism in the cholesterol 7α-hydroxylase promotor region seems to be involved in the determination of cholesterol and LDL-C responsiveness to a dietary fat challenge.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

13. The Effect of an Acute Fat Load on Endothelial Function after Different Dietary Regimens in Young Healthy Volunteers

Creator:
Tomáš Šejda, Kovář, J., Jan Piťha, Renata Cífková, Švandová, E., and Rudolf Poledne
Format:
print, bez média, and svazek
Type:
article, studie, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, Postprandial lipemia, Hypertriglyceridemia, Endothelial dysfunction, DietHypertriglyceridemia, 14, and 612
Language:
English
Description:
Attention has recently been focused on endothelial function after a single high-fat meal, i.e. on the anticipated direct atherogenic effect of triglyceride-rich lipoproteins. Our study was designed to investigate the effect of a low-fat diet given for four weeks followed by a high-fat diet for another four weeks. At the end of each dietary period, a non-invasive ultrasound investigation of endothelial function of the brachial artery was performed along with laboratory tests. Endothelial function was measured immediately before the dietary load and after three and six hours in 11 healthy volunteers. The results were expressed as percentage of the changes in artery diameter at rest and during hyperemia; the data were processed using computer technology. When compared to the low-fat regimen, the total cholesterol content rose after the high-fat diet from 4.28 mmol/l to 5.15 mmol/l (p<0.05) in the whole group of volunteers. There was no difference between both dietary regimens in baseline triglycerides. The brachial artery dilatation under basal conditions was 5.26±2.88 mm after the high-fat diet compared with the value of 3.13±3.01 mm (p<0.05) after the low-fat diet. When measured individually endothelial function in the whole group of volunteers in the course of the day, the degree of arterial dilatation after one month on low-fat diet was 3.13±3.0 %, 3.88±2.5 % and 5.23±3.3 % at single measurement. When comparing arterial dilatation at two closest measurements, a non-significant trend, p>0.05 was seen in either case. The following values were obtained after one month on the high-fat diet: 5.26±2.9 %, 4.47±1.7 %, and 6.2±3.6 %; again showing a non-significant trend of p>0.05. In this study, a single high-fat meal at the different dietary regimen did not significantly influence the vasoreactivity of the brachial artery in young volunteers., T. Šejda, J. Kovář, J. Piťha, R. Cífková, E. Švandová, R. Poledne., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

14. The effect of glucose when added to a fat load on the response of glucagon-like peptide-1 (GLP-1) and apolipoprotein B-48 in the postprandial phase

Creator:
Zemánková, K., Jolana Mrázková, Jan Piťha, and Kovář, J.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, inzulin, fyziologie, insulin, physiology, postprandial lipemia, triglyceride, glucose, GLP-1, 14, and 612
Language:
English
Description:
Increased and prolonged postprandial lipemia has been identified as a risk factor of cardiovascular disease. However, there is no consensus on how to test postprandial lipemia, especia lly with respect to the composition of an experimental meal. To address this question of how glucose, when added to a fat load, affects the selected parameters of postprandial lipemia, we carried out a study in 30 healthy male volunteers. Men consumed an experimental meal containing either 75 g of fat + 25 g of glucose (F+G meal) or 75 g of fat (F meal) in a control experiment. Blood was taken before the meal and at selected time points within the following 8 h. Glucose, when added to a fat load, induced an increase of glycemia and insulinemia and, surprisingly, a 20 % reduction in the response of both total and active glucagon -like peptide -1 (GLP -1) concentration. The addition of glucose did not affect the magnitude of postprandial triglyceridemia and TRL -C and TRL -TG concentrations but stimulated a faster response of chylomicrons to the test meal, evaluated by changes in apolipoprotein B -48 concentrations. The addition of glucose induced the physiological response of insulin and the lower response of GLP -1 to the test meal during the early postprandial phase, but had no effect on changes of TRL -cholesterol and TRL -TG within 8 h after the meal., K. Zemánková, J. Mrázková, J. Piťha, J. Kovář., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

15. The response of hepatic transcriptome to dietary cholesterol in Prague Hereditary Hypercholesterolemic (PHHC) rat

Creator:
Vlachová, M., Marie Heczková, Milan Jirsa, Rudolf Poledne, and Kovář, J.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, cholesterol, dietní jídla, genetika, genová exprese, hypercholesterolémie, diet, genetics, gene expression, hypercholesterolemia, rat, 14, and 612
Language:
English
Description:
To understand the pathogenesis of hypercholesterolemia in Prague hereditary hypercholesterolemic (PHHC) rat, we analyzed the response of hepatic transcriptome to dietary cholesterol in PHHC and control Wistar rats. Male PHHC and Wistar rats were fed chow (C), 5 % fat (palm kernel oil) (CF) or 1 % cholesterol + 5 % fat (CHOL) diet for three weeks. Hepatic transcriptome was analyzed using Affymetrix GeneChip arrays. No differences were found in the effect of both control diets (C and CF) on lipid metabolism and gene expression of 6500 genes. Therefore, these data were pooled for further analysis. Dietary cholesterol induced accumulation of cholesterol and triacylglycerols in the liver in both strains and hypercholesterolemia in PHHC rats. However, there were no differences in response of hepatic transcriptome to CHOL diet. On the other hand, several genes were found to be differently expressed between both strains independently of the diet. Two of those genes, Apof and Aldh1a7, were studied in more detail, and their role in pathogenesis of hypercholesterolemia in PHHC rats could not been corroborated. In conclusion, the hypercholesterolemia in PHHC rats is due to physiological response of hepatic transcriptome to dietary cholesterol in different genetic background., M. Vlachová, M. Heczková, M. Jirsa, R. Poledne, J. Kovář., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public