Publications (9)28.28 Total impact
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Article: Short-term exercise combined with Acipimox administration induces an increase in plasma ACTH and its subsequent fall in the recovery phase in bulimic women.
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ABSTRACT: OBJECTIVE: Free fatty acids (FFA)-adrenocorticotropin (ACTH) feedback loop between adipose tissue and the hypothalamic-pituitary centres in the brain has been suggested to be affected by the exercise and by administration of anti-lipolytic drugs. Also leptin may be affected by exercise. Dysfunction of FFA-leptin-ACTH secretion might be involved in binge eating and subsequent purging as is the case in bulimia nervosa (BN). METHODS: In the present single-blind, randomized study, we explored responses of plasma ACTH, leptin and FFA concentrations to exercise (45 min, 2W/kg of lean body mass [LBM]) with Acipimox (Aci), an anti-lipolytic nicotinic acid analogue, or placebo randomly received in nine women with BN and nine healthy women. RESULTS: The exercise with Aci administration resulted in plasma ACTH (p < 0.001) and leptin increase higher in BN patients and a decrease in the plasma FFA levels in both groups. The falling of plasma ACTH (p < 0.01) levels in the post-exercise recovering phase (90-minute) with Aci administration is more expressed in BN patients. The exercise induced an increase in plasma ACTH (p < 0.05) and FFA levels and a decrease in the plasma leptin level in both groups. CONCLUSIONS: We demonstrated that the Aci-induced elevation in plasma ACTH (p < 0.001) levels after the exercise higher in BN patients and that the falling of plasma ACTH (p < 0.01) levels in the post-exercise recovering phase (90-minute) with Aci administration is suppressed only in BN patients, while Aci increased plasma leptin levels in this recovering phase more in BN patients. Therefore, these observations led us to suggesting that FFA-leptin-ACTH are involved in the dysregulation of neuroendocrine profile in this syndrome and that Aci affects a FFA-independent mechanism. In conclusion, Aci can be considered acceptable in the treatment of eating disorders, and it may also serve as an alternative low-dose dexamethasone suppression test (LDDST) in these patients. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12612000309886.Regulatory Peptides 01/2013; · 2.11 Impact Factor -
Article: Comparison of a high-carbohydrate and highprotein breakfast effect on plasma ghrelin, obestatin, NPY and PYY levels in women with anorexia and bulimia nervosa.
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ABSTRACT: BACKGROUND: The present study investigated plasma levels of gut-brain axis peptides ghrelin, obestatin, NPY and PYY after consumption of a high-carbohydrate (HC) and high-protein (HP) breakfast in patients with anorexia nervosa, bulimia nervosa and in healthy controls. These peptides play an important role in regulation of energy homeostasis and their secretion is disturbed under condition of eating disorders. As various types of consumed macronutrients may induce different plasma hormone responses, so we examined these responses in women patients with eating disorders and compared them with those of healthy controls. METHODS: We examined plasma hormone responses to HC and HP breakfast in patients with AN (n = 14; age: 24.6 +/- 1.8 years, BMI: 15.3 +/- 0.7), BN (n = 15; age: 23.2 +/- 1.7 years, BMI: 20.5 +/- 0.9) and healthy controls (n = 14; age: 24.9 +/- 1.4 years, BMI: 21.1 +/- 0.8). Blood samples were drawn from the cubital vein, the first blood drawn was collected before meal, and then 30, 60, 90, 120 and 150 min after breakfast consumption. Plasma hormone levels were determined by commercially available RIA kits. RESULTS: Fasting and postprandial plasma obestatin levels were significantly increased in both AN and BN patients, while plasma ghrelin levels were significantly increased in AN patients only. After breakfast consumption, plasma levels of ghrelin and obestatin decreased, although they were still above the range of values of healthy controls. Fasting NPY plasma levels were significantly increased in AN and BN patients and did not change postprandially. Fasting PYY levels were comparable in AN, BN and healthy controls, but postprandially significantly increased after HP breakfast in AN and BN patients. Different reactions to breakfast consumption was found for ghrelin and PYY among investigated groups, while for obestatin and NPY these reactions were similar in all groups CONCLUSIONS: Significant increase of obestatin and NPY in AN and BN patients may indicate their important role as the markers of eating disorders. Different reactions of ghrelin and PYY to breakfast consumption among groups suggest that role of these hormones in regulation of energy homeostasis can be adjusted in dependence to acute status of eating disorder.Nutrition & Metabolism 06/2012; 9(1):52. · 2.88 Impact Factor -
Article: A higher response of plasma neuropeptide Y, growth hormone, leptin levels and extracellular glycerol levels in subcutaneous abdominal adipose tissue to Acipimox during exercise in patients with bulimia nervosa: single-blind, randomized, microdialysis study.
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ABSTRACT: Neuropeptide Y (NPY) is an important central orexigenic hormone predominantly produced by the hypothalamus, and recently found to be secreted in adipose tissue (AT). Acipimox (Aci) inhibits lipolysis in AT and reduces plasma glycerol and free fatty acid (FFA) levels. Exercise and Aci are enhancers of growth hormone (GH) and NPY secretion and exercise may alter leptin levels. We expect to find abnormal neuropeptidergic response in plasma and AT in patients with bulimia nervosa (BN). We hypothesize that Aci influences these peptides via a FFA-independent mechanism and that Aci inhibits lipolysis through a cyclic adenosine monophosphate (cAMP)-dependent pathway. Dysregulations of the AT-brain axis peptides might be involved in binge eating as is the case in BN. The objective of this study was to determine the responses of plasma NPY, GH, leptin, FFA and glycerol levels to exercise in BN patients and healthy women (C) given the anti-lipolytic drug Aci or placebo. The secondary objective of this study was to compare the responses of extracellular glycerol levels and plasma glycerol levels to exercise alone or together with Aci administration in BN patients and C women. Extracellular glycerol was measured in vivo in subcutaneous (sc) abdominal AT using microdialysis. Eight BN and eight C women were recruited for this single-blind, randomized study. Aci or placebo was given 1 hour before the exercise (45 min, 2 W/kg of lean body mass [LBM]). NPY, GH, leptin, FFA, glycerol plasma and AT glycerol levels were measured using commercial kits. The primary outcome of this study was that the exercise with Aci administration resulted in plasma NPY and GH increase (after a 45-minute exercise) and leptin (after a 90-minute post-exercise recovering phase) increased more in BN patients. The secondary outcomes of this study were that the exercise with Aci administration induced a higher decrease of extracellular glycerol in BN patients compared to the C group, while the exercise induced a higher increase of glycerol concentrations in sc abdominal AT of BN patients. Plasma glycerol levels decreased more in BN patients and plasma FFA levels were depressed in both groups after the exercise with Aci administration. The exercise induced similar increases in plasma NPY, GH, FFA and glycerol levels, and a similar decrease in the plasma leptin level in both groups. We confirm the results of a single-blind, randomized, microdialysis study, i.e. that the Aci-induced elevation in plasma NPY and GH levels during the exercise is higher in BN patients and that Aci increased plasma leptin levels in the post-exercise recovering phase (90-minute) more in BN patients. The post-exercise rise (45-minute) in AT glycerol is much more attenuated by acute Aci treatment in BN patients. Simultaneously, we found facilitated turnover of plasma glycerol after the exercise together with Aci administration in BN. Our results support the hypotheses that Aci exerts an effect on the FFA-independent and cAMP-dependent mechanism. Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12611000955910.Nutrition & Metabolism 11/2011; 8(1):81. · 2.88 Impact Factor -
Article: Changes of orexin A plasma levels in girls with anorexia nervosa during eight weeks of realimentation.
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ABSTRACT: Orexin A (OXA) is a hypothalamic neuropeptide involved in regulation of food intake and nutritional status. There are multiple disturbances of neuropeptide signaling described in girls with anorexia nervosa (AN), but OXA levels have not been addressed in this population to date. Therefore, we analyzed OXA levels of AN girls in this study. OXA (radioimmunoassay/RIA/method), leptin, insulinlike growth factor-1 (IGF-1), and insulinlike growth factor-1 binding protein-3 (IGFBP-3) levels were measured before and after 8 weeks of realimentation in 36 girls with AN and in 14 healthy controls (control group: CG). Average weight increased significantly in AN during the study (p < .0001), while plasma levels of OXA decreased (before realimentation: 56.2 ± 2.4 pg/ml; after realimentation: 47.5 ± 1.4 pg/ml; p = .0025). OXA levels before realimentation differed from levels in the CG (47.15 ± 2.6 pg/ml, p = .034), but not afterward. We did not find any correlation between OXA and age, height, weight, BMI; or IGF-1, IGFBP-3, and leptin levels. OXA levels in untreated AN patients differ significantly from healthy subjects and decrease during realimentation. These findings indicate that OXA may be involved in the nutritional regulation of malnourished children and adolescents.International Journal of Eating Disorders 09/2011; 44(6):547-52. · 2.95 Impact Factor -
Article: Acipimox during exercise points to an inhibitory feedback of GH on ghrelin secretion in bulimic and healthy women.
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ABSTRACT: Ghrelin is predominantly produced by the stomach and the growth hormone (GH)-ghrelin feedback loop between the stomach and the pituitary gland has recently been suggested. The disruption of the gut-brain axis might be involved in bulimia nervosa (BN). We investigated responses of plasma GH, ghrelin, and neuropeptide Y (NPY) concentrations to exercise or to exercise after the administration of the antilipolytic drug Acipimox (Aci) in seven BN patients and seven healthy women (C). Aci was administered 1h before exercise (45 min, 2 W/kg of lean body mass/LBM/). Ghrelin, GH, NPY, free fatty acids (FFA) and glycerol plasma levels were measured during the test using commercial kits. The exercise induced an increase in plasma GH, NPY and FFA in both groups and a decrease in plasma ghrelin levels only in BN patients. Exercise after Aci administration resulted in an increase in plasma GH, and a decrease in plasma ghrelin in both groups; NPY increased more in BN patients. Exercise-induced FFA increase was depressed after Aci. We conclude that the Aci-induced suppression in plasma ghrelin levels during exercise in both groups suggests a negative feedback of GH on ghrelin secretion. Observed changes in plasma FFA levels were not related to changes in GH and ghrelin levels.Regulatory Peptides 02/2011; 167(1):134-9. · 2.11 Impact Factor -
Article: The effect of short-term exercise on plasma leptin levels in patients with anorexia nervosa.
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ABSTRACT: Plasma leptin concentrations are markedly reduced in malnourished patients with anorexia nervosa (AN). Whether the long-term underweight and low-fat stores affect the leptin response to exercise remains unknown. We investigated the effect of 45-minute cycle ergometer exercise (2 W kg-1 of lean body mass [LBM]) on plasma leptin, norepinephrine (NE), glycerol, and insulin levels in 10 patients with AN and in 15 healthy age-matched women (C). Plasma leptin levels immediately and 90 minutes after the exercise bout were significantly reduced compared with basal leptin levels in both AN and C groups (P<.05). Compared with the control trial, leptin levels were significantly lower immediately and 90 minutes after exercise in the AN group (P<.05) but not in the C group. Basal and exercise-induced plasma glycerol and NE levels did not differ significantly between the groups. Basal and exercise-induced plasma insulin levels were significantly lower in the AN group compared with the C group (P<.05). In conclusion, we demonstrated that a single bout of low-intensity exercise significantly reduces plasma leptin levels in patients with AN. In healthy women, exercise had no effect on lowering leptin concentrations beyond the diurnal decrease that occurs in the absence of exercise. Neither NE nor insulin are responsible for the different response of leptin to exercise in AN.Metabolism 05/2007; 56(4):497-503. · 2.66 Impact Factor -
Article: Adipose tissue resistin levels in patients with anorexia nervosa.
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ABSTRACT: Resistin is a specific fat-derived hormone that affects fuel homeostasis and insulin action in rodents. However, its role in human physiology and pathophysiologic conditions, such as malnutrition, remains uncertain. To enhance understanding of the role of resistin in the pathophysiology of anorexia nervosa (AN), we measured plasma resistin levels in 13 women with a restrictive type of AN and in 16 healthy age-matched women (control). Further, we measured resistin levels in the subcutaneous adipose tissue of eight women from the AN group and eight women from the control group with an in vivo microdialysis technique (CMA/107 pump, CMA/60 catheters, CMA Microdialysis AB, Solna, Sweden). Body mass index, percentage of body fat, fasting plasma leptin and insulin, and homeostasis model assessment index for insulin resistance were severely decreased in patients with AN compared with the control group. Plasma resistin levels were significantly decreased in patients with AN (P < 0.05), whereas subcutaneous adipose tissue resistin levels were significantly increased in patients with AN compared with the control group (P < 0.05). In both groups, plasma resistin levels showed no significant relation to resistin in dialysate, percentage of body fat, body mass index, homeostasis model assessment index for insulin resistance, and fasting plasma leptin levels. We demonstrated that AN is associated with decreased plasma resistin levels and increased resistin levels in extracellular space of the abdominal adipose tissue. Plasma resistin levels in patients with AN or in healthy normal-weight women were not directly related to body mass index, percentage of body fat, plasma leptin levels, and insulin sensitivity.Nutrition 11/2006; 22(10):977-83. · 3.03 Impact Factor -
Article: Changes of noradrenergic activity and lipolysis in the subcutaneous abdominal adipose tissue of hypo- and hyperthyroid patients: an in vivo microdialysis study.
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ABSTRACT: Thyroid function plays an important role in the regulation of overall metabolic rate and lipid metabolism. However, it is uncertain whether thyroid hormones directly affect lipolysis in adipose tissue and to what extent those changes contribute to overall metabolic phenotype. Our study was designed, using the microdialysis technique, to determine basal and isoprenaline-stimulated local lipolysis and to determine local concentrations of lipolysis-regulating catecholamines in abdominal subcutaneous adipose tissue in 12 patients with hypothyroidism, 6 patients with hyperthyroidism, and 12 healthy control subjects. Plasma norepinephrine (NE) concentrations in hypothyroid subjects were significantly higher than in the control and hyperthyroid groups. In contrast, systemic, adipose NE levels in hypothyroid patients were decreased relative to controls. Hyperthyroidism, on the other hand, resulted in four-fold higher adipose NE levels. Basal lipolysis measured by glycerol concentrations in adipose tissue was significantly attenuated in hypothyroid patients and markedly increased in hyperthyroid patients in comparison with the control group. In addition to differences in basal lipolysis, hypothyroidism resulted in attenuated, and hyperthyroidism in enhanced, lipolytic response to local stimulation with beta(1,2)-adrenergic agonist isoprenaline. These results demonstrate that lipolysis in abdominal subcutaneous adipose tissue is strongly modulated by thyroid function. We suggest that thyroid hormones regulate lipolysis primarily by affecting local NE concentration and/or adrenergic postreceptor signaling.Annals of the New York Academy of Sciences 07/2004; 1018:541-9. · 3.15 Impact Factor -
Article: Effects of hypo- and hyperthyroidism on noradrenergic activity and glycerol concentrations in human subcutaneous abdominal adipose tissue assessed with microdialysis.
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ABSTRACT: Thyroid hormones play a major role in lipid metabolism. However, whether they directly affect lipolysis locally in the adipose tissue remains unknown. Therefore, we measured abdominal sc adipose tissue norepinephrine (NE), basal, and isoprenaline-stimulated lipolysis in 12 hypothyroid patients (HYPO), six hyperthyroid patients (HYPER), and 12 healthy controls by in vivo microdialysis. Adipose tissue NE was decreased in HYPO and increased in HYPER compared with controls (90.4 +/- 2.9 and 458.0 +/- 69.1 vs. 294.9 +/- 19.5 pmol/liter, P < 0.01). Similarly, basal lipolysis, assessed by glycerol assay, was lower in HYPO and higher in HYPER than in controls (88.2 +/- 9.9 and 566.0 +/- 42.0 vs. 214.3 +/- 5.1 micromol/liter P < 0.01). The relative magnitude of isoprenaline-induced glycerol increase was smaller in HYPO (39 +/- 19.4%, P < 0.05 vs. basal) and higher in HYPER (277 +/- 30.4%, P < 0.01) than in controls (117 +/- 5.6%, P < 0.01). The corresponding changes in NE after isoprenaline stimulation were as follows: 120 +/- 9.2% (P < 0.05), 503 +/- 113% (P < 0.01), and 267 +/- 17.2 (P < 0.01). In summary, by affecting local NE levels and adrenergic postreceptor signaling, thyroid hormones may influence the lipolysis rate in the abdominal sc adipose tissue.Journal of Clinical Endocrinology & Metabolism 01/2004; 88(12):5605-8. · 6.50 Impact Factor
Top Journals
Institutions
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2006–2013
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Institute of Endocrinology
Praha, Hlavni mesto Praha, Czech Republic
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2004
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National Institutes of Health
Bethesda, MD, USA
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