1a_It has been known for many years that baroreflex sensitivity is lowered in hypertensive patients. There are several known factors implicating this association, e.g. high blood pressure leads to remodeling of the carotid arterial wall, to its stiffness and to a diminished activation of baroreceptors; leptin released from a fatty tissue activates the sympathetic nervous system etc. On the other hand, low baroreflex sensitivity (BRS, usually quantified in ms/mmHg) can be inborn. Studies on primary hypertension in children and adolescents have brought new information about the role of baroreflex in the development of an early stage of primary hypertension. BRS lower than 3.9 ms/mmHg was found in 5 % of healthy subjects. This value approaches the critical value for the risk of sudden cardiac death in patients after myocardial infarction and corresponds to the value present in hypertensive patients. A decreased BRS and BRSf (baroreflex sensitivity expressed in mHz/mmHg, index independent of the mean cardiac interval), was found not only in children with hypertension, but also in those with white-coat hypertension. This is in accordance with a single interpretation. The decrease of BRS/BRSf precedes a pathological blood pressure increase., 2a_The contribution of obesity and BRS/BRSf to the development of hypertension in adolescents was also compared. Both factors reach a sensitivity and a specificity between 60 % and 65 %, but there is no correlation between the values of the body mass index and BRS either in the group of hypertensive patients or in healthy controls. If a receiver operating curve (sensitivity versus specificity) is plotted for both values together using logistic regression analysis, a sensitivity higher than 70 % and a specificity over 80 % are reached. This means that low baroreflex sensitivity is an independent risk factor for the development of primary hypertension. Studies demonstrate that adolescents with increased blood pressure and with BRS under 7 ms/mmHg should be given care and intensively motivated to change their lifestyle including a change in diet and increase in physical activity., and N. Honzíková, B. Fišer.
In this study, susceptibility of inbred C57BL/6 and outbred NMRI mice to monosodium glutamate (MSG) obesity or diet-induced obesity (DIO) was compared in terms of food intake, body weight, adiposity as well as leptin, insulin and glucose levels. MSG obesity is an early-onset obesity resulting from MSG-induced lesions in arcuate nucleus to neonatal mice. Both male and female C57BL/6 and NMRI mice with MSG obesity did not differ in body weight from their lean controls, but had dramatically increased fat to body weight ratio. All MSG obese mice developed severe hyperleptinemia, more remarkable in females, but only NMRI male mice showed massive hyperinsulinemia and an extremely high HOMA index that pointed to development of insulin resistance. Diet-induced obesity is a late-onset obesity; it developed during 16-week-long feeding with high-fat diet containing 60 % calories as fat. Inbred C57BL/6 mice, which are frequently used in DIO studies, both male and female, had significantly increased fat to body weight ratio and leptin and glucose levels compared with their appropriate lean controls, but only female C57BL/6 mice had also significantly elevated body weight and insulin level. NMRI mice were less prone to DIO than C57BL/6 ones and did not show significant changes in metabolic parameters after feeding with high-fat diet., R. Matyšková, L. Maletínská, J. Maixnerová, Z. Pirník, A. Kiss, B. Železná., and Obsahuje bibliografii a bibliografické odkazy
In this study, we describe changes of plasma levels of the hypothalamic neuropeptide orexin A in obese children during the reduction of body weight and its relationship to other biochemical and anthropometrical parameters. We measured orexin A fasting plasma levels by the RIA method in 58 obese children - 33 girls and 25 boys; mean age 13.1±0.38 years (range 7-18.5) before and after 5 weeks of weight-reduction therapy. Leptin, IGF-1, and IGFBP-3 levels were measured in all the subjects and were compared to orexin A levels and anthropometrical data. Average weight in subjects before weight-reduction was 74.2±2.79 kg and after weight-loss 67.4±2.60 kg (p<0.0001). Orexin A levels before the therapy were 33.3±1.97 pg/ml and after the therapy 51.7±3.07 pg/ml (p<0.0001). Levels of orexin A were not significantly different between girls and boys (p=0.7842). We found negative correlation between orexin A and age (r = -0.5395; p<0.0001), body height (r = -0.4751; p=0.0002), body weight (r = -0.4030; p=0.0017) and BMI (r = -0.2607; p=0.0481). No correlation was found between orexin A and IGF-1, IGFBP-3 or leptin. Orexin A plasma levels increased during body weight loss, whereas the reverse was true for leptin levels. These findings support the hypothesis that orexin A may be involved in regulation of nutritional status in children., J. Bronský, J. Nedvídková, H. Zamrazilová, M. Pechová, M. Chada, K. Kotaška, J. Nevoral, R. Průša., and Obsahuje bibliografii a bibliografické odkazy
Reduced physical activity and abundant energy intake are two most common factors leading to uncontrolled body weight gain. But these factors are not under entire internal consciousness control; they are also partially genetically determined and are affected by for example food marketing practices. In addition to these two widely accepted factors, there are some other factors, whose could also contribute to the recent increase of obesity prevalence. For example, non-exercise activity thermogenesis, sleeping habits, more stable inside room temperatures (using of heating and air conditioning), high prescription of medications with weight gain as side effect, psychosocial factors, unfavourable socioeconomic status and unpleasant urban environment are the background factors which should not be omitted if obesity/BMI determination should be fully understood and kept under control. In conclusion, unhealthy life style is necessary, but not sufficient for obesity development., J. A. Hubáček., and Obsahuje seznam literatury
Accumulation of adipose tissue in lower body lowers risk of cardiovascular and metabolic disorders. The molecular basis of this protective effect of gluteofemoral depot is not clear. The aim of this study was to compare the profile of expression of inflammation-related genes in su bcutaneous gluteal (sGAT) and abdominal (sAAT) adipose tissue at baseline and in response to multiphase weight-reducing dietary intervention (DI). 14 premenopausal healthy obese women underwent a 6 months’ DI consisting of 1 month very-low-calorie-diet (VLCD), subsequent 2 months’ low-calori e-diet and 3 months’ weight maintenance diet (WM). Paired samples of sGAT and sAAT were obtained before and at the end of VLCD and WM periods. mRNA expression of 17 genes (macrophage markers, cytokines) was measured using RT-qPCR on chip-platform. At baseline, there were no differences in gene expression of macrophage markers and cytokines between sGAT and sAAT. The dynamic changes induced by DI were similar in both depots for all genes except for three cytokines (IL6, IL10, CCL2) that differed in their response during weight maintenance phase. The results show that, in obese women, there are no major differences between sGAT and sAAT in expression of inflammation-related genes at baseline conditions and in response to the weight-reducing DI., L. Mališová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Fibroblast growth factor 21 (FGF21) is a novel metabolic regulator produced primarily by the liver that exerts potent antidiabetic and lipid-lowering effects in animal models of obesity and type 2 diabetes mellitus. This hormone contributes to body weight regulation and is strongly involved in the response to nutritional deprivation and ketogenic state in mice. The principal sites of metabolic actions of FGF21 are adipose tissue, liver and pancreas. Experimental studies have shown marked improvements in diabetes compensation and dyslipidemia after FGF21 administration in diabetic mice and primates. Positive metabolic actions of FGF21 without the presence of apparent side effects make this factor a hot candidate to treat type 2 diabetes and accompanying metabolic diseases. The aim of this review is to summarize the current knowledge about the metabolic effects of FGF21 including some preliminary data on changes of its levels in humans with a special emphasis on its therapeutic potential in type 2 diabetes mellitus., I. Dostálová, D. Haluzíková, M. Haluzík., and Obsahuje seznam literatury
Recent studies have demonstrated that adipocyte fatty acid binding proteins (FABP) may play a role in the etiopathogenesis of insulin resistance. The aim of our study was to assess serum FABP levels in obese patients with type 2 diabetes mellitus (T2DM) before and after 3 months of treatment with PPAR-α agonist fenofibrate (F) and to explore the relationship of FABP to biochemical parameters and measures of insulin sensitivity assessed by hyperinsulinemic-isoglycemic clamp. We measured biochemical parameters by standard laboratory methods, insulin sensitivity by hyperinsulinemic-isoglycemic clamp and serum concentrations of FABP by commercial ELISA kit in 11 obese females with T2DM before and after three months of treatment with PPAR-α agonist fenofibrate and in 10 lean healthy control women (C). Serum FABP levels were 2.5-fold higher in T2DM group relative to C and were not affected by fenofibrate treatment (C: 20.6±2.1 μg/l, T2DM before F: 55.6±5.7 μg/l, T2DM after F: 54.2±5.4 μg/l, p<0.0001 for C vs. T2DM before F). Hyperinsulinemia during the clamp significantly suppressed FABP levels in both C and T2DM group. FABP levels positively correlated with BMI, triglyceride levels, blood glucose, glycated hemoglobin, atherogenic index and insulin levels. An inverse relationship was found between FABP and HDL levels, metabolic clearance rate of glucose, M/I and MCRglc/I sensitivity indexes. We conclude that FABP levels are closely related to BMI, parameters of insulin sensitivity, HDL levels and measures of diabetes compensation. This combination makes FABP a valuable marker of metabolic disturbances in patients with type 2 diabetes mellitus., M. M. Haluzík ... [et al.]., and Obsahuje seznam literatury
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