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E Baczyńska

Publications and source records attributed to E Baczyńska.

7 recordsLinked to original sources

Influence of insulin on cholesterol removal from macrophages and cholesterol ester uptake by HepG2 cells.

The fact that an increased blood insulin level is observed in patients with coronary artery disease (CAD) confirms the hypothesis that insulin promotes the development of atherosclerosis. The low high-density lipoprotein (HDL) concentration observed in such patients may contribute to alteration in reverse cholesterol transport and promote the accumulation of sterols in vascular tissue. We examined the effect of insulin (20-1000 microU mL-1) on cholesterol efflux into HDL3 particles from human blood monocyte/macrophages and rat peritoneal macrophages preloaded with labelled cholesterol esters, and the influence of insulin on the accumulation of sterols by rat liver cells and HepG2 cell line in vitro models. Insulin at concentrations up to 250 microU mL-1 inhibited the efflux of cholesterol from rat macrophages and promoted high uptake of sterols by both types of hepatic cells. Pharmacological concentrations higher than 250 microU mL-1 exerted the opposite effect. In the case of human macrophages, an insulin concentration of 20 microU mL-1 increased cholesterol removal, whereas 100-200 microU mL-1 insulin inhibited cholesterol removal from cells, and very high concentrations (> 350 microU mL-1) again increased cholesterol removal. We have shown that insulin excess counteracts the beneficial effects of HDL in removing cellular cholesterol and, therefore, may promote development of atherogenesis.

Animals↗

Poland and United States Collaborative Study on Cardiovascular Epidemiology. A comparison of HDL cholesterol and its subfractions in populations covered by the United States Atherosclerosis Risk in Communities Study and the Pol-MONICA Project.

HDL cholesterol (HDL-C) levels are inversely related to coronary heart disease (CHD) risk, and HDL-C distributions vary among countries. Poland is one of the few developed countries in which CHD rates are increasing at the same time that US rates have been falling, but whether these differences are explained by differences in risk factors such as HDL-C has not been determined. To examine this possibility, levels of HDL-C and its subfractions were compared in US and Polish urban and rural men and women aged 45 to 64 years. Age-adjusted HDL-C means were 0.20 mmol/L higher in urban Polish men and 0.37 mmol/L higher in rural Polish men than in their US counterparts (P < .0001); means in urban Polish women were 0.06 mmol/L higher (P < .05) and in rural Polish women 0.09 mmol/L higher (P < .001) than in their US counterparts. Adjustment for age, education, alcohol intake, smoking, BMI, heart rate, and menopause status (in women) had little effect on differences. Means of HDL2 and HDL3 levels showed similar between-country differences, although differences were minimal for HDL2 in urban men and women, and HDL3 means did not differ between rural women. BMI was inversely related to HDL-C and both subfractions in all gender-country-site strata (P < .001), and alcohol was directly related to HDL-C (P < .001) in all strata except Polish women. Cigarette smoking was negatively related to HDL-C and both subfractions in all US samples except HDL2 in urban men, whereas in Polish samples, significant associations were found only in urban women for HDL-C and in rural and urban women for HDL3. Age, heart rate, and education showed inconsistent or no association with HDL-C and its subfractions in either country. This profile of HDL-C and its subfractions in Polish samples contrasts sharply with the opposite trend in CHD mortality rates, which suggests either that other risk factors may account for the trends or that the relationship between HDL-C and CHD may differ between the two countries.

Age Factors↗

Influence of SIN-1 and sodium nitroprusside (NANP) on ox-LDL metabolism in macrophages.

Effects of NO-donors (3-morpholinosydnonimine-SIN-1 and sodium nitroprusside NaNP) on the accumulation and degradation of oxidized LDL (ox-LDL) by macrophages were studied. Ox-LDL, but not native-LDL (n-LDL) suppressed the LPS-stimulated biosynthesis of NO by macrophages. SIN-1 at low concentrations < 100 microM was without any effect while SIN-1 at high concentration (300 microM) and NaNP (30-300 microM) stimulated the accumulation and degradation of ox-LDL by macrophages. The pretreatment of macrophages with NG-monomethyl-L-arginine (L-NMMA, 3 microM) for 24 hours had the same stimulatory effect. The inhibition of endogenous formation of NO, by L-NMMA profoundly changed the pattern of action of NO-donors on ox-LDL catabolism by macrophages; the stimulatory action of SIN-1 was transformed to the inhibitory action on the accumulation and degradation of ox-LDL whereas NaNP lost its stimulatory action entirely. Our interpretation of this unexpected interactions between SIN-1, NaNP and L-NMMA is as follows. Endogenous NO in macrophages inhibits the accumulation of ox-LDL and therefore, the stimulatory effect of L-NMMA has been overcome by exogenous NO from SIN-1. However, NO at high concentrations promotes lipid accumulation in macrophages and thereby, in the absence of L-NMMA, SIN-1 at high concentrations and NaNP produced a paradoxical stimulatory effect in macrophages. NaNP is not a proper NO-donor and its mode of action differed from that of SIN-1. In conclusion, NO at low physiological concentrations keeps scavenger receptors of macrophages downregulated and hence endogenous NO may show anti-atherogenic properties.

Animals↗

[Characteristics of the main risk factors of coronary disease among the population of Warsaw and rural agricultural population of the Tarnobrzeg province].

Basing on results of first screening of the Pol-MONICA Project in 1984 in two centres that is the Tarnobrzeg province and two districts of Polish capital Warsaw (Praga South and Praga North) the level of 11 main coronary disease risk factors was compared in 2469 men and 2729 women. The following 5 risk factors were statistically significant for both men and women: the Durnin index of body fat content, the total cholesterol concentration in the plasma, triglyceride level, numbers of daily meals. The mean level of two factors that is the HDL-cholesterol concentration and the HDL-cholesterol/total cholesterol ratio was lower in the Warsaw sample what speaks in favor of concept that the ischemic heart disease threat is greater in that population. Among men the Warsaw population exhibited moreover the significantly higher value of diastolic blood pressure as well as of Quetelet body mass index; age and numbers of cigarettes smoked daily has also been higher in that population. In women from the Tarnobrzeg province ++ the diastolic blood pressure was higher than that in the Warsaw population. The two populations studied showed also highly significant differences so far as the complex of all 11 features is concerned what enabled the qualification of 72.3% of men, and 68.4% of women as belonging to the big city population or to the agricultural-industrial population using the discriminant Fisher function.

Adult↗

[Effect of inter-population differences in the levels of selected factors on the differences in arterial blood pressure].

According to the Pol-MONICA program the random selected population samples were studied in inhabitants of Warsaw or the Tarnobrzeg province . After excluding from analysis the subjects treated with the hypotensive++ or hypolipemic drugs the differences between populations studies with regard to range of mean pressure value, except systolic pressure (RRs) in women, appeared significant ones. In populations studied the arterial blood pressure (CTK) was influenced by: age, sex, education, family history with regard to the circulatory system, the alcohol intake, smoking, heart action frequency the Quetelet coefficient value, triglyceride concentration and daily sodium intake. After analysis of inter-population differences in values of above factors the mean RRs values in populations studied did not differed significantly whereas differences in mean values of diastolic pressure (RRr) were highly statistically significant.

Adult↗

Pol-MONICA Cracow on-going study: initial findings.

The findings after the first year of the study are presented. The study population is 282,052 men and women aged 25-64 years, current residents of rural Tarnobrzeg Voivodeship. The population is characterized by a declining linear trend in ischemic heart disease (IHD) mortality in men aged 35-44 years. The myocardial infarction (MI) incidence (per 100,000 residents) is 233 in men and 68 in women. The MI death rates (per 100,000 residents) are 128 for men and 29 for women. The MI 28-day case fatality is 44% for men and 41% for women. The most frequent risk factors are: smoking in men (58%) and obesity in women (40%). Around one-quarter of the men and of the women are hypertensive. The rates for hypercholesterolemia are 9% in men and 13% in women.

Adult↗