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P Bobek

Publications and source records attributed to P Bobek.

At least 37 records · Page 2Linked to original sources
PubMed1996

[Antioxidative enzyme activity in the blood of healthy persons].

BACKGROUND: Under physiological conditions the dynamic balance between the reactive oxygen production and detoxication is maintained. OBJECTIVES: The study was aimed at the detection of the activity of antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) in erythrocytes and the level of malondialdehyde (MDA) in the serum of healthy subjects, their relation to age, body weight, sex, smoking, and the possible correlation between individual parameters. METHODS: The authors have examined 128 healthy volunteers (57 men and 71 women) from 20 to 72 years of age. The results were statistically evaluated by means of the ANOVA programme. RESULTS: The group of healthy people had a large dispersion of interindividual activities of antioxidant enzymes and MDA levels. Age and weight were reversely correlated to the CAT activity in erythrocytes. The CAT activity was significantly higher in women than in men, and the GPx activity was lower in smokers than in non-smokers. The rest of investigated parameters were not significantly influenced by sex of examined people and smoking. Mutual correlation between individual enzymes were highly significant. CONCLUSIONS: A large dispersion of activities of the investigated enzymes and MDA levels in healthy individuals do not allow to make a standard use of these parameters in clinical practice. (Tab. 5, Fig. 2, Ref. 20.).

Adult↗
PubMed1995

Oyster mushroom (Pleurotus ostreatus) reduces the activity of 3-hydroxy-3-methylglutaryl CoA reductase in rat liver microsomes.

The effect of dried oyster mushroom (Pleurotus ostreatus) on cholesterol (C) content in serum, in lipoproteins and in liver, and on the activity of 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) reductase in liver microsomes, was studied in male rats (strain Wistar, initial body weight 75 g) fed on low-cholesterol (9 mg/100 g) and high-cholesterol (0.3%) diets. Addition of 5% oyster mushroom to both diets reduced significantly the C-content in serum (by 30%), in very-low- and low-density lipoproteins (in a 1:1 ratio to the decrease of total serum C) and in liver (by 50%), as well as the activity of HMG-CoA reductase (by more than 30%).

Animals↗
PubMed1995

Dietary oyster mushroom (Pleurotus ostreatus) accelerates plasma cholesterol turnover in hypercholesterolaemic rat.

The effect of adding 5% powdered oyster mushroom (Pleurotus ostreatus) during 12 weeks on kinetic parameters of cholesterol metabolism was studied in male rats (Wistar, initial body weight 85 g) fed a semisynthetic diet containing 0.3% of cholesterol. The plasma cholesterol decay curve (examined for the final 29 days of the experiment after a single dose of cholesterol-4-14C) was evaluated by mathematical analysis using a two-pool model of plasma cholesterol metabolism. The oyster mushroom in the diet reduced the half-times of both exponentials resulting in lower calculated values (by 28%) of total entry of cholesterol into the body cholesterol pool (absorption+endogenous synthesis) and lower sizes of both pools (with slower and faster cholesterol exchange). The rate of cholesterol exchange between the pools was enhanced and the rate of total clearance of cholesterol from the system (metabolic turnover rate of cholesterol i.e. the rate of degradation and excretion of cholesterol from the organism) was enhanced by 50%. The oyster mushroom diet effectively prevented the progress of hypercholesterolaemia (decrease by 38%) and cholesterol accumulation in liver (decrease by 25%) that were induced by the cholesterol diet.

Animals↗
PubMed1994

Mechanism of hypocholesterolemic effect of oyster mushroom (Pleurotus ostreatus) in rats: reduction of cholesterol absorption and increase of plasma cholesterol removal.

The content of cholesterol in the serum and liver of male Wistar rats fed, for the period of 8 weeks shortly after weaning, a diet containing 0.3% of cholesterol was reduced by 33 and 27% by the addition of 5% of dried oyster mushroom powder. Although the level of serum triacylglycerols was not affected by oyster mushroom, their content in liver of rats on mushroom diet was reduced by 41%. Very-low-density lipoproteins and low-density lipoproteins participated by 55 and 38%, respectively, in the total reduction of serum cholesterol. Cholesterol content in high-density lipoproteins was not significantly affected by oyster mushroom. Cholesterol absorption as determined by dual-isotope plasma ratio method was significantly reduced by 14% with oyster mushroom diet. Similarly, this diet increased by 42% the fractional catabolic rate of cholesterol determined by the analysis of decay curve of [4-14C]cholesterol.

Animals↗
PubMed1994

[Activity of the antioxidant system in patients with idiopathic proctocolitis and the effect of 5-aminosalicylic acid (Salofalk)].

There is a close relationship between inflammation and reactive oxygen species (ROS). Primary source of ROS are activated leucocytes. Antioxidant system protects organism against the deleterious effect of ROS. The aim of the present study was to follow the activity of antioxidant system in blood and colonic mucosa of 17 patients with idiopathic proctocolitis. All patients were treated with 5-aminosalicylic acid (Salofalk), 7 patients with a combination of prednison. The following biochemical parameters were ascertained: malondialdehyde (MDA) and ceruloplasmin in serum, glutathione (GSH) and activities of superoxide dismutase, catalase and glutathione peroxidase in erythrocytes and colonic mucosa. Before treatment there was found: an increase of MDA and all antioxidant enzyme activities, an a decrease of GSH. After 3 weeks of therapy in 59% of patients, initial clinical remission was observed without serious improvement of biochemical parameters. After 10 weeks of therapy the clinical course improved in all patients, a significant decrease of MDA and activities of all antioxidant enzymes as well as an increase of GSH were stated. The authors assume that IP was positively affected by 5-ASA, and in some patients by its combination with prednisom. The effect of 5-ASA is based on its known antiinflammatory impact and its functioning as a "scavanger" of free radicals (or ROS). (Tab. 1, Fig. 3, Ref. 23.)

Adult↗
PubMed1994

The effect of dietary protein and sucrose on the diabetic rat kidney.

The effect of 3 months feeding with diets of different protein and sucrose content (9% casein + 70% sucrose vs. 18% casein + 61% sucrose) on the development of diabetic nephropathy and changes in serum lipid spectrum was investigated in rats with insulin-dependent diabetes (streptozotocin 45 mg.kg-1). Metabolism of diabetic animals (before the nutritional regimen) was characterized by hyperglycaemia, moderate hyperlipidemia, lipid accumulation in the liver and elevated creatinine concentration in the blood. Kidney weight and protein content were not significantly changed. Histological picture of kidneys showed initial changes of glomerular structure. After three months hyperlipoproteinaemia was more accentuated in animals given either of the two diets, the kidneys were hypertrophic with a higher protein content and displayed morphological changes of diabetic nephropathy. Animals given the low-protein diet developed smaller morphological changes both in glomeruli and tubuli. The study indicates that dietary protein and not hyperlipoproteinaemia is the major factor, which may significantly influence the progress of diabetic nephropathy.

Animals↗
PubMed1994

[Cholesterol levels in lipoproteins and various intake of amino acids in an experiment].

In the conditions of physiological nutrient content and variable amino-acid mixtures made of casein K, gluten G and KG combination (1:1, standard diet), the 10-week effect of amino acids (until the age of 105 days, end of maturation stage) was investigated in growing rats with respect to protein utilization (net protein ratio) and to the values of lipid parameters at the end of the experiment (cholesterol, triacylglycerols, atherogenic indexes, cholesterol distribution into lipoprotein classes). A significant decrease in NPR for gluten, an insignificant decrease for casein in the growth period are related to the amino acid score of limiting amino acids--they determine rate of proteosynthesis and potential biological value--amount percentage of amino acids of the given diet for plastic processes of proteins (AS for KG 69, for K 67, for G 28; BHp for KG 83.1, for K 70.0, for G 54.1). Since day 105 amino acid utilization is balanced in all groups, hence it does not depend upon the quality of aminograms (lower rate of proteosynthesis in comparison with the growth period, for which the values of limiting amino acids are sufficiently high). Significantly decreased values of cholesterolemia and triacylglycerolemia for gluten food, insignificantly higher values for casein food, are in direct correlations with the values of Lys/Arg, Met/Arg, Met, Lys, and in indirect correlations with Arg and Arg+Glu+Gly. Distribution of HDL-cholesterol as a cholesterol percentage in HD lipoproteins is higher by 8.7% for gluten and all atherogenic indexes are significantly decreased in contrast to casein food, in which a slight decrease in HDL-cholesterol and insignificantly higher atherogenic indexes were recorded.

Amino Acids↗
PubMed1993

Influence of water and ethanol extracts of the oyster mushroom (Pleurotus ostreatus) on serum and liver lipids of the Syrian hamsters.

Extracts from the dried and ground fungus were prepared with water and with 30%, 60% and 85% ethanol, and thickened in vacuum. The whole fungus and extracts were added to the hyperlipidemic diet in amounts equivalent to 3% of the whole fungus. After 6 weeks the whole fungus, its water as well as 30% and 60% ethanol extracts have significantly reduced the contents of cholesterol (C) and triacylglycerols (TG) in the serum. The C and TG contents of the liver were reduced by 34-48% (in the case of TG insignificantly when applying the water and 60% ethanol extracts). The 85% ethanol extracts reduced the C and TG levels in both serum and liver statistically insignificantly by 18-22%. The reduction of serum C by addition of the whole fungus and its water and 30% ethanol extract was decisively affected by the reduction in the C contents in the very low density fraction of lipoproteins.

Animals↗
PubMed1993

The mushroom Pleurotus ostreatus reduces secretion and accelerates the fractional turnover rate of very-low-density lipoproteins in the rat.

In male rats fed a diet containing 1.5% cholesterol and 5% of dried mushroom (Pleurotus ostreatus) a significantly reduced accumulation of cholesterol in serum (by 45%) and the liver (by 15%) was observed at the end of the 12th week of the experiment. The decrease in serum cholesterol level by more than 90% is a consequence of the decreased cholesterol concentration of very-low-density lipoproteins (VLDL) and of low-density lipoproteins. Consumption of P. ostreatus reduces the total VLDL entry into the circulation by 19% and accelerates (by 49%) fractional turnover rate of VLDL.

Animals↗
PubMed1993

Effect of the oyster fungus on glycaemia and cholesterolaemia in rats with insulin-dependent diabetes.

We have investigated the effect of a diet containing of 4% oyster fungus (Pleurotus ostreatus) and 0.1% cholesterol on glycaemia and hyperlipoproteinaemia in rats with insulin-dependent diabetes (streptozotocin 45 mg/kg). After two months, the rats with diabetes kept on the oyster fungus diet, had a significantly lower basal and postprandial glycaemia, the insulinaemia remained unchanged. The cholesterol concentration was decreased by more than 40%, the lipoprotein profile was upgraded by the decrease of the cholesterol in both the low density and very low density lipoproteins. The oyster fungus decreased the cholesterol accumulation in the liver and had no significant effects on the levels of serum and liver triacylglycerols.

Animals↗
PubMed1993

Effect of the oyster fungus on glycaemia and cholesterolaemia in rats with insulin-dependent diabetes.

We have investigated the effect of a diet containing of 4% oyster fungus (Pleurotus ostreatus) and 0.1% cholesterol on glycaemia and hyperlipoproteinaemia in rats with insulin-dependent diabetes (streptozotocin 45 mg/kg). After two months, the rats with diabetes kept on the oyster fungus diet, had a significantly lower basal and postprandial glycaemia, the insulinaemia remained unchanged. The cholesterol concentration was decreased by more than 40%, the lipoprotein profile was upgraded by the decrease of the cholesterol in both the low density and very low density lipoproteins. The oyster fungus decreased the cholesterol accumulation in the liver and had no significant effects on the levels of serum and liver triacylglycerols.

Animal Nutritional Physiological Phenomena↗
PubMed1993

Antioxidative state of the myocardium and kidneys in acute diabetic rats.

The influence of acute diabetes (8 days), induced by streptozotocin (45 mg.kg-1 body weight) on myocardial and renal antioxidative conditions was investigated. The animals were given subtherapeutical doses of insulin (Interdep 6 U. kg-1 body weight, s.c.). Considerably increased levels of malondialdehyde (MDA), as well as of superoxide dismutase (SOD) and catalase (CAT) activity were found in the myocardium of diabetic animals. The oxidized glutathione (GSSG) level and glutathione peroxidase (GSH-PX) activity remained unchanged. The reduced glutathione (GSH) level as well as the activity of glutathione S-transferase (GST) were significantly lower. The activity of GSH-PX in the kidneys of diabetic rats increased by 60% and that of GST by 105%, respectively. CAT and SOD activity values were unchanged.

Acute Disease↗
PubMed1993

Protein synthesis in growing and adult rats on casein and gluten nutrition.

Male weaning rats were put on a diet with a physiological nutrient combination adjusted for age, milk casein (E/N = 0.79) and wheat gluten (E/N = 0.30) being the sources of protein. The net protein ratio (NPR) was evaluated weekly until 140 days of age. On days 70 and 140, L-(U-14C)-tyrosine was administered intraperitoneally and 12 h later specific tyrosine activity was determined in the protein fraction of liver and muscle by measuring the incorporation of the labeled amino acid in order to assess protein synthesis over the corresponding time period. Regression lines describing the relationship between animals' weight, age and protein source suggested that the daily weight increase was 6.99 g between days 30-77, 2.97 g between days 77-105 and 0.64 g between days 105-140. Muscle tyrosine levels in rapidly growing animals aged 70 days were 91.0 micrograms/g/12 h for casein and 65.6 micrograms/g/12 h for gluten. Liver tyrosine levels were 336.4 and 189.6 micrograms/g/12 h, respectively. The differences observed at this age were highly significant. In adult animals (140 days old) there were non-significant differences between tyrosine levels in the casein- and gluten-fed groups. The isotope study clearly showed that protein synthesis was reduced in growing and developing animals on vegetable nutrition, which is deficient in essential amino acids, (especially the limiting amino acid lysine, crucial for the utilization of all other amino acids in peptide chain synthesis). The low rate of amino acid utilization found in animals younger than 105 days is consistent with the findings obtained by the isotope method.

Aging↗
PubMed1992

[The effect of body weight reduction on apolipoprotein levels in obese patients].

In 16 obese male patients lipid and apolipoprotein A-I and B in serum were assessed before and after weight reduction. The mean age of the subjects was 34.7 +/- 2.7 years, the mean body weight 124.4 +/- 4.0 kg and the mean BMI 39.1 +/- 1.5 kg/m2. After 10 weeks on a low-energy diet of 2500-6000 kJ/day a decline of body weight was observed on average by 14% of the initial value. The total triacylglycerolaemia declined by 46% (p less than 0.02). The total cholesterol level declined by 12% (ns), HDL-cholesterol by 7% (ns), LDL-cholesterol by 8% (ns). The apo A-I did not change during weight reduction, apo B declined by 13% (ns). The ratio of apo B to apo A-I declined by 12.5% (p less than 0.05). The presented results indicate that after weight reduction of obese patients by a low-energy diet the risk of atherosclerosis declines as the apo B/apo A-I ratio declines.

Adult↗
PubMed1991

Cholesterol-lowering effect of the mushroom Pleurotus ostreatus in hereditary hypercholesterolemic rats.

We studied the effect of the edible mushroom Pleurotus ostreatus (4% in diet containing 1% of cholesterol) on serum and liver lipids in female rats with hereditary enhanced sensitivity to alimentary cholesterol. We found that the consumption of the mushroom-containing diet prevented serum cholesterol increase which was manifested at the end of the 4th week of the experiment. At the end of the 7th week of the experiment the cholesterolemia was lowered by almost 40% as compared with control animals kept on the same diet but without the mushroom. The decrease in serum cholesterol levels is a consequence of the decreased cholesterol concentrations of very-low-density lipoproteins and of low-density lipoproteins.

Animals↗