Aldosterone plays a key role in maintaining the homeostasis of the whole organism. Under some circumstances, aldosterone can contribute to the progression of cardiovascular diseases, including coronary artery disease. This study demonstrates that aldosterone associates negatively with some lipidogram parameters and positively with the concentration of homocysteine. These associations are characteristic for coronary artery disease and are not present in control subjects. The findings also indicate that in vitro aldosterone stimulates homocysteine production by rat adrenal glands, which may explain the associations observed with coronary artery disease. Moreover, we have found that aldosterone significantly modulates in vitro platelet reactivity to arachidonate and collagen - aldosterone increases the pro-aggregatory action of collagen, but decreases the pro-aggregatory potential of arachidonate. Therefore, the findings of these in vitro and ex vivo experiments indicate the existence of new pathways by which aldosterone modulates lipid- homocysteine- and platelet-dependent atherogenesis., K. Karolczak, P. Kubalczyk, R. Glowacki, R. Pietruszynski, C. Watala., and Seznam literatury
Impressive advances in molecular genetic techniques allow to analyze the effects of natural selection on the development of human genome. For example, the trend towards blonde hair and blue eyes was documented. The approach to analyze possible effects of natural selection on the evolution of recent phenotypes with high risk of cardiovascular disease has not been described yet. A possible effect on the evolution of two main risk factors - hypercholesterolemia and hypertension - is presented. The close relationship of non-HDL cholesterol blood concentration to the proportion of pro-inflammatory macrophages in human visceral adipose tissue might be a result of long-lasting natural selection. Individuals with higher proportion of this phenotype might also display a higher ability to fight infection, which was very common in human setting from prehistory until Middle Ages. Successful battle against infections increased the probability to survive till reproductive age. Similar hypothesis was proposed to explain frequent hypertension in African Americans. A long-lasting selection for higher ability to conserve sodium during long-term adaptation to low sodium intake and hot weather was followed by a short-term (but very hard) natural selection of individuals during transatlantic slave transport. Only those with very high capability to retain sodium were able to survive. Natural selection of phenotypes with high plasma cholesterol concentration and/or high blood pressure is recently potentiated by high-fat high-sodium diet and overnutrition. This hypothesis is also supported by the advantage of familial hypercholesterolemia in the 19th century (at the time of high infection disease mortality) in contrast to the disadvantage of familial hypercholesterolemia during the actual period of high cardiovascular disease mortality., R. Poledne, J. Zicha., and Seznam literatury
Patients with chronic renal failure are prone to cardiovascular complications. The mechanisms and the assessment of the risk of cardiovascular diseases (CVD) in this population are of interest. The purpose of this study was to investigate the traditional and potential risk factors for the development of CVD and their contribution to ischemic heart disease (IHD) and variation in carotid intima media thickness (IMT) in hemodialyzed patients (HD). Twenty-one chronically HD patients and nineteen healthy volunteers were recruited. Studied parameters were intima-media thickness, body mass index (BMI), mean arterial blood pressure (MAP), hemoglobin, fibrinogen (Fbg), serum lipids, lipoprotein (a) [Lp(a)], total homocysteine (tHcy). Mean carotid IMT, tHcy, Fbg and Lp(a) were higher in HD patients compared to the control group. There were no differences in cholesterol (tCh) and triglycerides between these groups. Patients with ischemic heart disease were older and they had higher values of carotid IMT, tCh, triglycerides, Fbg and Lp(a). There were no differences in MAP, time on dialysis and tHcy between the two subgroups (with vs without IHD). Carotid IMT correlated positively with age (r=0.68, p=0.001), BMI (r=0.50, p=0.02), tCh (r=0.58, p<0.01), LDL- cholesterol (r=0.55, p=0.01) and Fbg (r=0.57, p<0.01) but not with tHcy or Lp(a) in the patients group. Carotid intima media thickness thus reflects the risk for ischemic heart disease in hemodialyzed patients. Elevated fibrinogen concentration and dyslipidemia influence arterial remodelling.