a1_The genes that cause or increase susceptibility to essential hypertension (EH) and related an imal models remain unknown. Their identification is unlikely to be realized with current genetic approaches, because of ambiguities in the genotype-phenotype relationships in these polygenic disorders. In turn, the phenotype is not just an aggregate of traits, but needs to be related to specific components of the circulatory control system at different stages of EH. Hence, clues about important genes must come through the phenotype, reversing the order of current approaches. A recent systems analysis has highlighted major differences in circulatory control in the two main syndromes of EH: 1) stress-and-salt-related EH (SSR-EH) - a constrictor hypertension with low blood volume; 2) hypertensive obesity - SSR-EH plus obesity. Each is initiated through sensitization of central synapses linking the cerebral cortex to the hypothalamic defense area. Several mechanis ms are probably involved, including cerebellar effects on baroreflexes. The result is a sustained increase in sympathetic neural activity at stimulus levels that have no effect in normal subjects. Subsequent progression of EH is largely thro ugh interactions with non-neural mechanisms, including changes in concentration of vascular autacoids (e.g. nitric oxide) and the amplifying effect of structural changes in large resistance vessels. The rising vasoconstriction increases heterogeneity of blood flow, causing rarefaction (decreased microvascular densit y) and deterioration of vital organs. SSR-EH also increases food intake in response to stress, but only 40% of these individual s develop hypertensive obesity. Their brain ignores the adiposity signals that normally reduce eating., a2_Hyperinsulinemia masks the sympathetic vasoconstriction through its dilator action, rais es blood volume, whilst renal nephropathy and other diabetic complications are common. In each syndrome the neural and non-neural determinants of hypertension provide targets fo r identifying high BP genes. Reading the genome from the phenotype will require new approaches, such as those used in developmental genetics. In addition, transgenic technology may help verify hypotheses and examine whether an observed effect is through single or multiple mechanisms. To obtain answers will require substantial collaborative efforts between physiologists and geneticists., P. I. Korner., and Obsahuje bibliografii
Recent studies focused on epicardial fat, formerly relatively neglected component of the heart, have elucidated some of its key roles. It possesses several properties that can distinguish it from other adipose tissue depots. Its unique anatomical location in the heart predisposes the epicardial fat to be an important player in the physiological and biochemical regulation o f cardiac homeostasis. Obesity is associated with an increase in epicardial fat mass. Excess of cardiac fat can contribute to greater left ventricular mass and work, diastolic dysfunction and attenuated septal wall thickening. Imbalance in adipokines levels secreted in autocrine or paracrine fashion by epicardial fat can contribute to the activation of the key atherogenic pathways in the setting of metabolic syndrome. Epicardial fat has also been identified as an important source of pro-inflammatory mediato rs worsening endothelial dysfunction, eventually leading to coronary artery disease. Increased production of pro-inflammatory factors by epicardial fat can also contribute to systemic insulin resistance in patients undergoing cardiac surgery. Here we revie w the most important roles of epicardial fat with respect to heart disease in the context of other underlying pathologies such as obesity and type 2 diabetes mellitus., Z. Matloch, T. Kotulák, M. Haluzík., and Obsahuje bibliografii
Gastrointestinal hormones play an important role in the neuroendocrine regulation of food intake and postprandial satiety. Ghrelin is a 28-amino acid orexigenic peptide produced mainly by the stomach that is involved in both the long-term regulation of body weight and the short-term regulation of postprandial satiety. Impairments in ghrelin secretion may in concert with other factors play an important role in the development of both obesity and anorexia nervosa. Despite an intensive research the critical factors regulating physiological postprandial ghrelin response in healthy individuals and its modification by the presence of obesity and anorexia nervosa are only partially understood. The potential contribution of ghrelin to the differences of diet- vs. surgical-induced weight losses in morbidly obese patients is now also being recognized. The aim of this review is to summarize the current knowledge about the physiology and pathophysiology of ghrelin and to discuss its potential in the prevention and/or treatment of obesity and anorexia nervosa., I. Dostálová, M. Haluzík., and Obsahuje seznam literatury
This review focuses on current knowledge of leptin biology and the role of leptin in various physiological and pathophysiological states. Leptin is involved in the regulation of body weight. Serum leptin can probably be considered as one of the best biological markers reflecting total body fat in both animals and humans. Obesity in man is accompanied by increased circulating leptin concentrations. Gender differences clearly exist. Leptin is not only correlated to a series of endocrine parameters such as insulin, glucocorticoids, thyroid hormones, testosterone, but it also seems to be involved in mediating some endocrine mechanisms (onset of puberty, insulin secretion) and diseases (obesity, polycystic ovary syndrome). It has also been suggested that leptin can act as a growth factor in the fetus and the neonate., R. Janečková., and Obsahuje bibliografii
The aim of our study was to explore the effects of regular aerobic exercise on anthropome tric, biochemical and hormonal parameters and mRNA expression of selected factors involved in metabolic regulations in subcutaneous adipose tissue of patients with obesity. Fifteen obese wome n with arterial hypertension underwent a three-month exercise program consisting of 30 min of aerobic exercise 3 times a we ek. Fifteen healthy lean women with no intervention served as a control group. Obese group underwent anthropometric measurements, blood sampling, subcutaneous adipose tissue (SCAT) biopsy and 24-h blood pressure monitoring at baseline and after three months of exercise, while control group was examined only once. At baseline, obese group had increased SCAT expression of proinflammatory cytokines and adipokines relative to control group. Three months of regular exercise improved anthropometric parameters, decreased CRP, blood glucose and HOMA-IR, while having no significant effect on lipid profile and blood pressure. Gene expressions in SCAT were not affected by physical activity with the exce ption of increased aquaporin-3 mRNA expression. We conclude that three months of regular exercise decrease systemic subc linical inflammation with only minor influence on the blood pressure and the endocrine function of subcutaneous fat., P. Trachta, J. Drápalová, P. Kaválková, V. Toušková, A. Cinkajzlová, Z. Lacinová, M. Matoulek, T. Zelinka, J. Widimský Jr., M. Mráz, M. Haluzík., and Obsahuje bibliografii
Cardiovascular diseases are the most common cause of mortality and morbidity in most populations. As the traditional modifiable risk factors (smoking, hypertension, dyslipidemia, diabetes mellitus, and obesity) were defined decades ago, we decided to analyze recent data in patients who survived acute coronary syndrome (ACS). The Czech part of the study included data from 999 males, and compared them with the post-MONICA study (1,259 males, representing general population). The Lithuanian study included 479 male patients and 456 age-matched controls. The Kazakhstan part included 232 patients and 413 controls. In two countries, the most robust ACS risk factor was smoking (OR 3.85 in the Czech study and 5.76 in the Lithuanian study), followed by diabetes (OR 2.26 and 2.07) and hypertension (moderate risk elevation with OR 1.43 and 1.49). These factors did not influence the ACS risk in Kazakhstan. BMI had no significant effect on ACS and plasma cholesterol was surprisingly significantly lower (P<0.001) in patients than in controls in all countries (4.80 ±1.11 vs. 5.76 ±1.06 mmol /l in Czechs; 5.32 ±1.32 vs. 5.71 ±1.08 mmol /l in Lithuanians; 4.88 ±1.05 vs. 5.38±1.13 mmol /l in Kazakhs/Russians). Results from our study indicate substantial heterogeneity regarding major CVD risk factors in different populations with the exception of plasma total cholesterol which was inversely associated with ACS risk in all involved groups. These data reflect ethnical and geographical differences as well as changing pattern of cardiovascular risk profiles., J. A. Hubacek, V. Stanek, M. Gebauerova, V. Adamkova, V. Lesauskaite, D. Zaliaduonyte-Peksiene, A. Tamosiunas, A. Supiyev, A. Kossumov, A. Zhumadilova, J. Pitha., and Obsahuje bibliografii
Tuková tkáň je endokrinní orgán produkující početné cytokiny. Změna v jejich regulacích může být příčinou patologických pochodů u obézních jedinců. Význam tukové tkáně ve vztahu k diabetu a ateroskleróze je intenzivně studován., Adipose tissue is an endocrine organ that produces numerous cytokines. Their dysregulations cause morbidity in obese individuals. The importance of this tissue in relation to diabetes and atherosclerosis is the subject of intense research., and Ilja Trebichavský, Petr Šíma.