Some lung cellular parameters reflecting inflammation after combined inhalation of amosite dust with cigarette smoke by rats.

Cellular changes were followed in lung cell suspensions after 175 day inhalation by rats of concentrations 30 mg/m3 or 60 mg/m3 of amosite asbestos every second day combined with daily exposure to cigarette smoke at 30 mg of total particulate matter (TPM)/m3 air. Concomitantly, lung inflammation was assessed by changes in the bronchoalveolar lavage fluid (BALF). A dose-dependent rise in the BALF inflammatory parameters was found. The rise of the proportion of binucleate (BNC) and multinucleate cells (MNC) in lung cell suspensions was also dose-dependent. It is concluded that, in the experimental assessment of effects of fibrogenic dusts, the number of BNC and of MNC in lung cell suspensions may serve as a useful semiquantitative biomarker of the inflammation.

Evaluation of bronchoalveolar lavage fluid cytotoxic parameters after inhalation exposure to amosite and wollastonite fibrous dusts combined with cigarette smoke.

The aim of this work was to compare the influence of amosite-asbestos and wollastonite fibrous dusts combined with cigarette smoke on chosen cytotoxic parameters of bronchoalveolar lavage fluid (BALF) in rats. Fisher 344 rats inhaled wollastonite or amosite fibrous dusts (60 or 30 mg x m(-3) air) one hour every two days combined with daily breathing of diluted mainstream tobacco smoke (30 mg of TPM x m(-3) air). The experiment lasted 6 months. After sacrifying the animals bronchoalveolar lavage (BAL) was performed and the viability and phagocytic activity of alveolar macrophages (AM), lactate dehydrogenase (LDH) and alkaline phosphatase activity (in the cell-free BALF), acid phosphatase (ACP) and cathepsin D activity (in cell-free BALF and BAL cell suspension) were examined. Exposure to amosite without tobacco smoke significantly decreased the viability of AM and increased the cathepsin D activity in BAL cells. Exposure to wollastonite significantly increased only the cathepsin D activity in BAL cells. Smoking significantly depressed the phagocytic activity of AM and amplified the amosite-induced increase of lysosomal enzyme activities--especially the activity of cathepsin D in BAL cells.

Effect of pleuran (beta-glucan from Pleurotus ostreatus) in diet or drinking fluid on colitis in rats.

The effects of pleuran, beta-glucan isolated from Pleurotus ostreatus, were studied in a model of acute colitis in rats. Pleuran was given either as a 2% food component or as 0.44% pleuran hydrogel drink over 4 weeks. Colitis was induced by intraluminal instillation of 4% acetic acid and after 48 h the extent of colonic damage and several biochemical parameters were examined. Pleuran supplementation both in food and in drinking fluid significantly decreased the disposition to colitis. The macroscopic damage score was reduced by 51% or 67% by pleuran diet and pleuran hydrogel drink, respectively. Pleuran did not influence the final body weights of rats but prevented significantly colonic wet weight increase which was observed in the control diet group. The enhanced activity of myeloperoxidase in the inflamed colonic segment was reduced by pleuran diets, reflecting decreased neutrophil infiltration. The colonic damage was accompanied by decreased activities of lysosomal enzymes--acid phosphatase and cathepsin D--in the control untreated group, whereas in the pleuran groups the decrease was significantly attenuated. Both pleuran regimens reduced the content of conjugated dienes in the colon, liver and erythrocytes. In contrast to this fact, activities of antioxidant enzymes in erythrocytes and the colon were not so greatly influenced. Significant increase was found only in the case of SOD activity in sham operated rat erythrocytes under influence of both pleuran regimes and in the case of GST activity in erythrocytes of pleuran hydrogel group. The mechanism of the described protective effect of pleuran is not yet fully understood. Our results indicate that the pleuran-enhanced antioxidant defence of the colonic wall against the inflammatory attack may have come into play.

Effect of pleuran (beta-glucan from Pleurotus ostreatus) on the antioxidant status of the organism and on dimethylhydrazine-induced precancerous lesions in rat colon.

The effect of pleuran (beta-1,3-D-glucan isolated from the oyster mushroom Pleurotus ostreatus) on the antioxidant status of the organism and on the development of precancerous aberrant crypt foci (ACF) lesions in the colon is studied in the male Wistar rat. A diet containing either 10% pleuran or 10% cellulose was compared with a cellulose-free diet and both were found to significantly reduced conjugated diene content in erythrocytes and in liver. Particularly significant was the reduction of conjugated dienes in the colon following pleuran administration. Diets containing cellulose and pleuran reduced glutathione peroxidase (GSH-PX) activity and increased catalase activity in erythrocytes. Pleuran increased superoxide dismutase (SOD) and GSH-PX activity (compared with the cellulose diet), and glutathione reductase activity (compared with the cellulose-free diet) in liver; and both diets reduced glutathione levels significantly in the colon. ACF lesions developed in the colon of all animals fed a cellulose-free diet; however, the incidence was reduced to 64% and 60% following the cellulose and pleuran diets, respectively. The highest average count of the most frequent small ACF lesions--and highest total count--was seen in animals fed a cellulose-free diet. Although ACF lesions were reduced by the cellulose diet, the more significant reduction statistically (>50%) was achieved with the pleuran diet.

Glutathione S-transferase polymorphisms influence the level of oxidative DNA damage and antioxidant protection in humans.

Glutathione S-transferase genotypes GSTT1, GSTM1, GSTP1 were characterised in 155 middle-aged men and compared with parameters of oxidative stress at the level of DNA and lipids, with antioxidant enzymes, and with plasma antioxidants in smokers and non-smokers. Smokers had on average significantly lower levels of Vitamin C, beta-carotene and beta-cryptoxanthin and higher amounts of oxidised purines and pyrimidines in lymphocyte DNA. The GSTM1 null genotype was associated with elevated glutathione as well as with higher Vitamin C concentration in plasma. Vitamin C was higher in GSTT1+ compared with GSTT1 null--as was glucose-6-phosphate dehydrogenase activity. The homozygous GSTP1 a/a genotype was associated with significantly higher levels of GST activity measured in lymphocytes, in comparison with the b/b genotype. Using multifactorial statistical analysis we found significant associations between smoking, GSTP1 genotype, plasma Vitamin C, and purine base damage in lymphocyte DNA. The difference in Vitamin C plasma levels between smokers and non-smokers was seen only with the GSTP1 b/b genotype. This group accounted also for most of the increase in purine oxidation in smokers. In contrast, the link between smoking and oxidised pyrimidines in DNA was seen only in the GSTT1 null group. It seems that polymorphisms in the phase II metabolising enzyme glutathione S-transferase may be important determinants of commonly measured biomarkers.

Effects of pleuran (beta-glucan isolated from Pleurotus ostreatus) on experimental colitis in rats.

The effects of pleuran, beta-1,3 glucan isolated from Pleurotus ostreatus, were studied in a model of acute colitis induced by intracolonic administration of acetic acid. There was a reduction of the colonic damage score, colonic wet weight and wet/dry weight ratio 48 h after single luminal 2% pleuran suspension pretreatment. Similar results were obtained after repeated intraperitoneal administration of pleuran in doses of 30 and 100 mg/kg. Pleuran given orally as a 10% food component over 4 weeks was effective in reducing the extent of mucosal damage, but did not prevent the increase of myeloperoxidase in the injured colonic segment. In the segment without macroscopic evidence of inflammation, myeloperoxidase activity was significantly lower as documented by histological examination. The results indicate a possible role of this immunomodulator in the treatment of ulcerative colitis.

The effect of red beet (Beta vulgaris var. rubra) fiber on alimentary hypercholesterolemia and chemically induced colon carcinogenesis in rats.

The effect of diet supplemented with 5% and 15% cellulose or with 15% fiber isolated from red beet (Beta vulgaris var. rubra) on the development of alimentary hypercholesterolemia and chemically induced colon carcinoma was studied in male Wistar rats. Hypercholesterolemia was induced by a diet containing 0.3% of cholesterol and colon carcinoma was induced by treatment with dimethylhydrazine (20 mg/kg, 12 doses applied s.c. in one-week intervals). Fibrous matter isolated from red beet contained 89% fiber, of which 9% was in water soluble form. Animals were killed 14 weeks after the application of dimethylhydrazine (i.e. 26 weeks after starting on the diets). Red beet fiber diet (and not the increased cellulose intake) caused a reduction of serum cholesterol and triacylglycerol levels (by 30 and 40%, respectively) and a significant increase in the fraction of cholesterol carried in HDL. This diet induced also a significant decrease (almost by 30%) of cholesterol content in aorta. Higher cellulose content in the diet and even more so the administration of red beet fiber caused a significant reduction of conjugated dienes content in plasma, erythrocytes and in liver. Also observed were increases in the activities of superoxide dismutase and catalase in erythrocytes and in colon and activities of glutathione peroxidase and glutathione-S-transferase in liver. The presence of both higher cellulose content and red beet fiber in the diet significantly reduced the incidence of precancerous lesions--aberrant crypt foci--in the colon. The diet containing red beet fiber did not affect significantly the incidence of colon tumours although the number of animals bearing tumours was reduced by 30%.

Hypocholesterolemic and antiatherogenic effect of oyster mushroom (Pleurotus ostreatus) in rabbits.

The addition of 10% dried fruiting bodies of oyster mushroom (Pleurotus ostreatus) to the diet containing 1% of cholesterol reduced serum cholesterol levels by 65% and cholesterol content in liver, heart, long extensor muscle and aorta of male rabbits (Chinchilla) by 60, 47, 25 and 80%, respectively. The decrease in total serum cholesterol was affected primarily (by 70%) by reduced cholesterol content in very-low-density lipoproteins (VLDL) while the contribution of high density lipoproteins (HDL) cholesterol increased by a factor of 3. Oyster mushroom diet reduced by 60-70% the content of conjugated dienes in plasma, erythrocytes and liver, however, it did not affect significantly the activities of antioxidant enzymes. Oyster mushroom diet reduced significantly the incidence of atherosclerotic plaques as estimated by sudanophilia (absence of positive-reaction in 3 of 5 animals) as well as plaque size (26% vs. 2% of the area with positive reaction in control and oyster mushroom-treated animals, respectively). While all animals on control diet showed atherogenic changes in aorta, oyster mushroom diet prevented the development of these changes in three animals. Fatty streaks and fibromatous plaques were found in the remaining two animals from this group. Oyster mushroom prevented the formation of atheroma plaques (found in three cases from the control diet group) and reduced the incidence of segmental injury of coronary arteria and of focal fibrosis of myocardium. Oyster mushroom caused lower incidence of foam cells in all types of lesions.

[The oyster mushroom (Pleurotus ostreatus) effectively prevents the development of atherosclerosis in rabbits]. / Hliva ústricovitá (Pleurotus ostreatus) efektívne bráni rozvoju aterosklerózy u králika.

The addition of 10% dried fruiting bodies of the oyster mushroom (Pleurotus ostreatus) to the diet containing 1% of cholesterol reduced serum cholesterol levels by 65% and cholesterol content in the liver, heart, long extensor muscle and aorta of male rabbits (Chinchilla) by 60; 47; 25 and 79%, respectively. Oyster mushroom diet reduced the content of conjugated dienes by 60-70% in the plasma, erythrocytes and liver. However, it did not significantly affect the activities of antioxidant enzymes. Oyster mushroom diet reduced significantly the incidence of atherosclerotic plaques as estimated by sudanophilia (absence of a positive reaction in 3 of 5 animals) as well as plaque size (26% vs. 2% of the area with a positive reaction in control and oyster mushroom-treated animals, respectively). While all animals on control diet showed atherogenic changes in the aorta, oyster mushroom diet prevented the development of these changes in three animals. Fatty streaks and fibromatous plaques were found in the remaining two animals from this group. The oyster mushroom prevented the formation of atheroma plaques (found in three cases from the control diet group) and reduced the incidence of segmental injury of the coronary artery and of focal fibrosis of the myocardium. The oyster mushroom caused lower incidence of foam cells in all types of lesions.

Dietary tomato and grape pomace in rats: effect on lipids in serum and liver, and on antioxidant status.

Addition of tomato and grape pomace to the cholesterol (0.3%) diet of male Wistar rats produced a dose-dependent effect. During the eight-week experiment, 5% pomace showed no effect; however, 15% pomace reduced serum cholesterol levels from 4.4 mmol/L to 2.5 mmol/L (tomato) and 2.0 mmol/L (grape). At a concentration of 15%, both tomato and grape pomace induced a redistribution of cholesterol in lipoproteins, resulting in a pronounced anti-atherogenic profile: reduced cholesterol concentration in very-low-density lipoprotein (VDL) (24% [tomato], 50% [grape]) and low-density lipoprotein (LDL) (3-fold, 3.6-fold). In addition, grape pomace increased cholesterol concentration in high-density lipoprotein (HDL) by 26%. Both types of pomace reduced the VLDL and LDL contribution to cholesterol transport in favour of HDL. Grape pomace (15%) produced a significant reduction in cholesterol and triacylglycerols in the liver and serum respectively. Diets containing tomato and grape pomace reduced plasma levels of conjugated dienes by 30-50%, and showed a tendency towards higher superoxide dismutase and glutathione peroxidase activity in the liver.

The effect of dried tomato, grape and apple pomace on the cholesterol metabolism and antioxidative enzymatic system in rats with hypercholesterolemia.

The effect of dried tomato, grape and apple pomace (5% in diet) on the cholesterol levels in serum and selected organs was studied in male Wistar rats fed a cholesterol diet (0.3%) shortly after weaning. Pomace of individual fruits contained 47.2, 67.0 and 46.2 g of total dietary fiber per 100 g of dry matter for tomato, grape and apple pomace, respectively. Corresponding values for the soluble components of the fiber were 10.3, 14.7 and 26.0%. None of the tested products affected the serum cholesterol levels. Tomato and apple pomace significantly reduced cholesterol level in liver by 15% and 11%, respectively, and all tested pomace species reduced cholesterol content in heart (by 18-21%). Triacylglycerol content was affected only by tomato pomace and solely in the heart. Cholesterol absorption measured by dual-isotope ratio method, was not significantly affected by the pomace, however, all products strongly reduced (up to the half of the original value) the activity of HMG-CoA reductase in liver and increased the fractional catabolic rate of plasma cholesterol (by 60-120%). All tested pomace reduced plasma levels of conjugated dienes and tomato and grape pomace exhibited this effect also in the liver. All tested pomace reduced the activities of antioxidant enzymes superoxid dismutase, catalase and glutathione peroxidase in erythrocytes (by 34-56%).

[Relation between fatty acid composition, vitamin e and malondialdehyde levels, and activity of antioxidant enzymes in the blood]. / Vzájomný vztah zlozenia mastných kyselín ku koncentrácii vitamínu E, k hladine malóndialdehydu a k aktivitám antioxidacných enzýmov v krvi.

The aim of our study was to determine the composition of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) in erythrocytes and to investigate their relation to the concentration of vitamin E (Vit E) in the plasma, level of malondialdehyde (MDA) in the serum and activities of antioxidant enzymes (AE) in erythrocytes. We examined 128 healthy volunteers (57 men and 71 women) at the ages ranging between 20 and 72. Fatty acids were assessed by gas chromatography, vitamin E by the HPLC method, MDA by the spectrophotometric method, GSH-Px by the kinetic method, CU, Zn-SOD by the Randox test. We have detected the following order in the proportion of fatty acids: SFA > PUFA > MUFA. The increase in PUFA and MUFA was in direct correlation with the concentration of MDA and AE activity, however in reverse correlation with Vit E. A reverse correlation was observed in the increase in SFA. We have found an increase in lipoperoxidation due to the increase in PUFA in erythrocytes in the group of healthy people. This state is concommited by an increase in the activity of antioxidant protection for the maintenance of the balance state. The authors assume that a decrease in Vit E can be caused by its increased "consumption" as the most effective antioxidant in lipid environment. (Tab. 2, Fig. 1, Ref. 27.)

[Relation between levels of vitamins C, E, A and beta-carotene and activity of antioxidant enzymes in the blood]. / Vztah hladín vitamínov C, E, A a beta-karoténu k aktivite antioxidacných enzýmov v krvi.

UNLABELLED: Antioxidant protection is procured by many enzymatic and non-enzymatic factors which maintain the physiological level of reactive forms of oxygen. The aim of this study was to determine the levels and relationship between concentrations of the selected non-enzymatic antioxidants in healthy people (vitamin C--Vit C, vitamin E--Vit E, beta-carotene-beta-Car and vitamin A--Vit A) in the serum, antioxidant enzymes, CuZn-superoxide dismutase--SOD, catalase CAT, glutathione peroxidase--GPx) in erythrocytes and malondialdehyde (MDA) in the serum. We have examined 128 volunteers (57 men and 71 women) at the age ranging between 20 and 72. The average levels of vitamins and beta-Carotene were detected near the lower level of normal values or below it, whilst the highest interindividual differences were detected in Vit C and Vit E. The level of Vit E indirectly correlated with SOD, GPx, MDA, but directly with CAT. On the contrary, the levels of Vit A directly correlated with SOD, GPx, MDA and indirectly with CAT. The levels of Vit C and beta-Carotene had no relation with the activities of antioxidant enzymes and the level of MDA. The direct correlation was between the levels of Vit C and Vit E, and Vit C and beta-Carotene. CONCLUSIONS: 1. A decrease in average levels of Vit A, C, E and beta-Carotene in the blood of the investigated group of healthy persons indicates their lower antioxidant protection. 2. The relation between Vit E, MDA, activities of GPx and SOD indicates the presumed mutually supplementing effect of these antioxidants in liquidation of products of lipoperoxidations. (Tab. 2, Fig. 3, Ref. 17.)

Effect of oyster mushroom (Pleurotus ostreatus) on pathological changes in dimethylhydrazine-induced rat colon cancer.

The effect of 5% of dried oyster mushroom (Pleurotus ostreatus) in the diet on the dimethylhydrazine (DMH)-induced colon carcinogenesis was studied in male Wistar rats. DMH in a dose of 20 mg/kg of body weight was applied to animals once a week during a period of 12 weeks. Mushroom diet was applied either after treatment with DMH for another 21 weeks or during the whole experiment. Mushroom diet reduced significantly the incidence of lymphoid hyperplasia foci when mushroom was supplemented during the whole experiment. Tumour lesions could be characterized either as carcinoma in situ, or as infiltrating adenocarcinoma. Mushroom diet did not affect significantly the incidence of tumours. Nevertheless, a reduction in total number of tumours was observed in both groups of animals fed mushroom diet. A significant reduction of the number of tumour foci of the type carcinoma in situ was observed in animals fed the oyster mushroom during the whole experiment. Also these animals had the significantly lower number of aberrant crypt foci. Mushroom diet reduced the ornithine decarboxylase activity in the colon and in the liver when oyster mushroom diet was administered during the whole experiment.

Dose- and time-dependent hypocholesterolemic effect of oyster mushroom (Pleurotus ostreatus) in rats.

The effect of the dose of oyster mushroom in the diet (1.0, 2.5, and 5.0%) and of the period of application (8, 16, 28, and 52 wk) on cholesterol accumulation in blood and body organs was studied in weanling male Wistar rats fed a diet containing 0.3% cholesterol. Reduction of cholesterol in serum and body organs was found to be dependent on the amount of dietary oyster mushroom administered. A negative correlation between the mushroom dose and cholesterol level was found after 8 and 28 wk of feeding (r=-0.9821 and -0.9803, respectively; P < 0.02 for both cases). The dose of 1% oyster mushroom did not affect cholesterol levels in serum or body organs. A significant reduction of cholesterol levels was observed in serum (31-46%) and liver (25-30%) at a dose of 5% of oyster mushroom for all periods. Reduced cholesterol content in very low-density lipoproteins (VLDL) was also observed at this level. The highest dose of oyster mushroom induced a decrease in conjugated diene levels in erythrocytes and an increase in the levels of reduced glutathione in the liver and stimulated the activities of catalase and glutathione peroxidase in the liver in the final period of the experiment.

[Regulation of cholesterol metabolism with dietary addition of oyster mushrooms (Pleurotus ostreatus) in rats with hypercholesterolemia]. / Regulácia metabolizmu cholesterolu hlivou ústricovitou (Pleurotus ostreatus) v diéte u potkana s hypercholesterolémiou.

BACKGROUND: It is generally accepted that lowering of serum cholesterol levels reduces the risk of atherosclerosis. Identification and characterization of natural substances with hypocholesterolemic activity useful in dietetic prevention or treatment of hypercholesterolemia is still relevant in countries with persistent progression of hypercholesterolemia. Addition of oyster mushroom (Pleurotus ostreatus), an industrially produced wood-rotting fungus, to the diet effectively reduced cholesterol accumulation in serum and liver of rats fed a cholesterol diet. The aim of a series of experiments was to explain the biochemical mechanism of this effect. METHODS AND RESULTS: Male Wistar rats fed a cholesterol (0.3%) diet shortly after weaning for a period of 8-10 weeks were used in the experiments. The addition of 5% of dried oyster mushroom to the diet had following effects: reduction of cholesterol level both in serum (5.12 +/- 0.55 vs. 3.44 +/- 0.16 mmol/l, p < 0.02) and liver (241 +/- 12 vs. 113 +/- 11 mmol/kg, p < 0.001); redistribution of cholesterol in favour of high-density lipoproteins; reduced production of very-low-density lipoproteins (135 +/- 7 vs. 96.5 +/- 5 mumol/h/kg, p < 0.001); reduced cholesterol absorption (61.2 +/- 2 vs. 53 +/- 2%, p < 0.02) and reduced HMG-CoA activity in liver (137 +/- 16 vs. 86 +/- 9 pmol/min/mg proteins, p < 0.02). Simultaneously, an increase in 7 alfa-hydroxylase activity in liver (17 +/- 1 vs. 22 +/- 1 pmol/min/mg proteins. p < 0.02) and bile acid excretion (7 +/- 0.9 vs. 11 +/- 0.5 mg/day/rat, p < 0.02) was observed. (Values shown are means +/- SEM.) CONCLUSIONS: Biochemical mechanism of hypocholesterolemic effect of oyster mushroom on cholesterol-fed rats includes reduced production of cholesterol-rich very-low-density and low-density lipoproteins which principally determine cholesterol levels in serum. This effect is related to decreased absorption and biosynthesis of cholesterol together with increase in cholesterol catabolism and excretion of degradation products-bile acids.

Dose-dependent hypocholesterolaemic effect of oyster mushroom (Pleurotus ostreatus) in rats.

A highly significant negative correlation (r=-0.981, p < 0.001) between the amount of oyster mushroom (Pleurotus ostreatus) in the diet and cholesterol levels in the serum has been found in male Wistar rats fed shortly after weaning by a a diet with 0.3% cholesterol. The addition of 1.0, 2.5 and 5.0% of oyster mushroom to the diet reduced the levels of serum cholesterol by 11, 31 and 46%, respectively. The diet containing 5% of oyster mushroom suppressed cholesterol accumulation in the liver and increased the fraction of cholesterol carried by high-density lipoproteins.

Oyster mushroom (Pleurotus ostreatus) reduces the production and secretion of very low density lipoproteins in hypercholesterolemic rats.

Oyster mushroom (Pleurotus ostreatus) reduced the production and secretion of nascent very low density lipoproteins in hypercholesterolemic rats. In male Wistar rats (initial body weight about 70 g) fed a semisynthetic diet with 0.3% of cholesterol, the addition of 5% of powdered oyster mushroom (Pleurotus ostreatus) to the diet reduced after 8 weeks the level of serum cholesterol (by 36%) and accumulation of cholesterol and triglycerides in liver (by 51 and 32%, respectively). The decreased levels of serum cholesterol were caused to the same extent by reduction of cholesterol content in very low density lipoproteins (VLDL) and in low density lipoproteins (LDL) (by 53 and 47%, respectively). Biosynthesis of all structural lipids of VLDL (phospholipids, cholesterol, triglycerides) in liver and incorporation of de novo synthesized lipids into secreted nascent VLDL (measured by simultaneous application of Na-acetate-1-14 C and Triton WR 1339 which inhibits peripheral lipolysis) was reduced by application of diet with oyster mushroom.

Effect of oyster mushroom (Pleurotus Ostreatus) and its ethanolic extract in diet on absorption and turnover of cholesterol in hypercholesterolemic rat.

The effect of the diet containing 5% of powdered oyster mushroom (Pleurotus ostreatus) or an equivalent amount of mushroom ethanolic extract on cholesterol content in serum and liver, on its distribution in lipoproteins, absorption and turnover was studied in male Wistar rats (initial body weight about 70 g) fed a diet with 0.3% cholesterol. 12 weeks of feeding with whole oyster mushroom or mushroom extract reduced cholesterol level in serum by 52 and 33%, respectively. However, cholesterol content in liver was reduced only by whole oyster mushroom (by 20%). Diminished serum cholesterol level was mediated in 60% by reduction of cholesterol in very-low-density lipoproteins. Both whole oyster mushroom and mushroom extract increased the concentration of cholesterol in high-density lipoproteins. Consuming whole oyster mushroom decreased cholesterol absorption (estimated by dual-isotope plasma ratio method) by nearly 16% while no significant effect of mushroom extract could be demonstrated. Feeding the diet containing whole oyster mushroom or its extract reduced the half-times of decay curve of cholesterol-4-14C by 29 and 35%, respectively and reciprocally increased the fractional catabolic rate of plasma cholesterol.

[Antioxidative enzyme activity in the blood of healthy persons]. / Aktivita antioxidacných enzýmov v krvi zdrav ch osôb.

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.).