The Peptidic GHS-R antagonist [D-Lys(3)]GHRP-6 markedly improves adiposity and related metabolic abnormalities in a mouse model of postmenopausal obesity

It was demonstrated that estrogen deficiency and consuming high fat (HF) diet enhanced orexigenic activity of ghrelin. Therefore, we hypothesized that antagonizing of ghrelin action would attenuate food intake and body weight in mice obese both from ovariectomy (OVX) and feeding a HF diet. Ghrelin receptor antagonist [D-Lys(3)]GHRP-6 after seven days of subcutaneous treatment markedly decreased food intake in OVX mice fed both HF and standard diets; furthermore, it reduced body weight and blood glucose, insulin and leptin, and increased β-hydroxybutyrate level and uncoupling-protein-1 mRNA in brown adipose tissue. Pair-feeding revealed that effect of [D-Lys(3)]GHRP-6 was primary anorexigenic. Estrogen supplementation reduced anorexigenic effects of [D-Lys(3)]GHRP-6. OVX [D-Lys(3)]GHRP-6 treatment in mice on HF diet resulted in markedly increased circulating level and liver expression of a major metabolic regulator, fibroblast growth factor 21. Our data suggest that ghrelin antagonists could be especially beneficial in individuals with common obesity combined with estrogen deficiency.

[Treatment of type 2 diabetes mellitus with GLP-1 agonists]

Increased prevalence of type 2 diabetes mellitus and its close clustering with obesity, arterial hypertension, dyslipidemia and other pathologies commonly referred to as metabolic or insulin resistance syndrome, represents one of the major health problem worldwide. The side effects of most of oral antidiabetics and insulin include increase in body weight and/or hypoglycemia that may limit its use in some patients. GLP-1 agonists are medicaments stimulating GLP-1 receptor similarly as endogenous GLP-1. These substances are in contrast to endogenous GLP-1 resistant to inactivation by ubiquitous enzyme dipeptidyl-peptidase 4 which enables its administration once or twice daily. GLP-1 agonists not only significantly improve diabetes compensation with minimal risk of hypoglycemia but also decrease body weight, blood pressure and improve numerous parameters of cardiovascular risk. The aim of this review is to summarize current knowledge with respect to use of GLP-1 agonists in the treatment of type 2 diabetes and its future perspectives. We will focus mostly on the two drugs that are currently available in Czech Republic--exenatide and liraglutide.

Effect of PPAR-γ agonist rosiglitazone on bone mineral density and serum adipokines in C57BL/6 male mice

Thiazolinediones (TZD) are widely used to treat type 2 diabetes, but their mechanism of action still remains only partially understood. Although the in vitro effects of TZD on osteoblastogenesis are well recognized, the in vivo consequences of these compounds on bone turnover are less understood and rather controversial. We demonstrate that a 9-week oral treatment with rosiglitazone in C57BL/6 male mice resulted in significant bone loss that was not dose dependent. The bones of the rosiglitazone-treated mice were characterized by reduction of bone density, and ash, calcium and phosphorus content. Rosiglitazone-treated mice had significantly thinner cortical widths. In contrast to serum TrACP expressed by action of osteoclasts, serum B-ALP activity, which serves as a marker of osteoblastic activity, was significantly lower in the rosiglitazone-fed animals. We did not find any differences in circulating levels of adipokines that could eventually explain rosiglitazone action. As the decrease in osteoblastic activity was demonstrated after rosiglitazone treatment, we anticipated changes in the haematopoietic stem cell pool. These cells seed in endosteal niches which comprise osteoblasts in order to maintain their stem cell function. In our study we did not see any significant influence of rosiglitazone administration on stem cells or any impairment in the lineage restrictions of rosiglitazone-treated stem cells. Our data demonstrate that rosiglitazone administration causes a loss of bone mass in cortical bone, possibly through a decrease in bone formation expressed by decreased B-ALP in male C57BL/6 mice. The levels of adipokines do not play any role.

Can adequate treatment influence the postembolization syndrome and cytokine release in patients undergoing iatrogenic renal artery embolization?

The complete renal artery embolization is an alternative to surgical nephrectomy in seriously ill patients. Iatrogenic embolization can be used in many different conditions. Refractory nephrotic syndrome represents a very rare indication for embolization. Complete renal artery embolization has usually been complicated by postembolization syndrome (PES) which is characterized by flank pain and fever. Possible immunologic contribution to the PES leads some authors to the administration of corticosteroids to the patients undergoing embolization. We report here a cohort of 13 patients undergoing complete embolization of total 21 kidneys due to refractory nephrotic syndrome non-responding to the various specific treatment regimes. We treated our patients undergoing renal artery embolization according to special protocol containing combination of antibiotic drugs and corticosteroids (CS) to diminish PES and evaluated its influence to the cytokine production. The incidence of PES was less frequent and milder in comparison with the historical group of patients. Significant decrease in plasma levels of tumor necrosis factor α during first post-embolization day (8.37 pre- vs. 5.74 pg/ml post-embolization, P=0.0002) could partially explain the reduction of PES symptoms. The procedure was not complicated by severe complications and represents an elegant alternative to surgical procedure. The accurate timing of the embolization remains a controversial point in this intervention.

[Insulin resistance and nitric oxide: molecular mechanisms and pathophysiological associations]

Subclinical inflammation that primarily arises in adipose tissue as a result of its excessive infiltration by immunocompetent cells represents one of the typical etiopathogenetic mechanisms underlying the development of insulin resistance and type 2 diabetes. Immunocompetent cells together with adipocytes are a major source of proinflammatory cytokines triggering proinflammatory cascades that in turn interfere with postreceptor insulin signalling cascade. Recent studies have suggested that inducible nitric oxide synthase plays a key role in this process. Obesity is associated with increased inducible nitric oxide synthase mRNA expression, with subsequent overproduction of nitric oxide and reactive nitrogen species leading to S-nitrosylation of proteins involved in insulin signalling cascade. These post-translational modifications decrease their activity and eventually lead to insulin resistance. Number of experimental studies demonstrated that inhibition of inducible nitric oxide synthase attenuates insulin resistance. The aim of this review is to summarize the current knowledge about the physiology and patophysiology of nitric oxide and inducible nitric oxide synthase with respect to its relationship to insulin resistance and to discuss the possibility of improvement of insulin resistance and type 2 diabetes mellitus by modulating inducible nitric oxide synthase activity.

[Adipose tissue hormones]

Adipose tissue had been traditionally considered a passive energy storage site without direct influence on energy homeostasis regulation. This view has been principally changed during early nineties by the discovery of hormonal production of adipose tissue. At present, the list of hormonally active substances of adipose tissue includes more than one hundred factors with paracrine or endocrine activity that play an important role in metabolic, food intake a inflammatory regulations and many other processes. Only minority of adipose tissue-derived hormones is produced exclusively in fat. Most of these factors is primarily put out by other tissues and organs. Adipose tissue-derived hormones are produced not only by adipocytes but also by preadipocytes, immunocompetent and endothelial cells and other cell types residing in fat. This paper summarizes current knowledge about endocrine function of adipose tissue with special respect to its changes in obesity. It also describes its possible role in the ethiopathogenesis of insulin resistance, atherosclerosis and other obesity-related pathologies.

Plasma concentrations of adipocyte fatty acid binding protein in patients with Cushing's syndrome

Serum adipocyte fatty acid-binding protein (FABP-4) concentrations are linked to human obesity and other features of metabolic syndrome. Patients with Cushing´s syndrome (CS) develop numerous features of metabolic syndrome due to chronic cortisol excess. Here we tested the hypothesis that chronically increased cortisol levels in CS patients may alter circulating levels of FABP-4. Fourteen patients with CS, 19 patients with simple obesity (OB) and 36 healthy control subjects (C) were included in the study. Serum FABP-4 concentrations were significantly higher in both CS and OB patients relative to C group, but they did not differ between CS and OB groups. In a combined population of all groups, serum FABP-4 levels correlated positively with BMI, body fat content, serum glucose, triglycerides, HbA1c and HOMA index and were inversely related to HDL-cholesterol, resting energy expenditure and freeT3 levels. We conclude that FABP-4 levels are significantly increased in both patients with simple obesity and obese patients with Cushing´s syndrome. We suggest that increased FABP-4 concentrations in CS patients are rather due to their excessive fat accumulation and related metabolic abnormalities than due to a direct effect of cortisol on FABP-4 production.

Estradiol supplementation helps overcome central leptin resistance of ovariectomized mice on a high fat diet

Ovariectomized mice on a high fat diet represent a model of diet-induced obesity during estrogen deficiency. Here, we tested the hypothesis that sensitivity to centrally administered leptin in ovariectomized mice with diet-induced obesity could be restored by estrogen supplementation. Ovariectomized C57BL/6 female mice were fed either a standard or high fat diet until they were 27 weeks old. Ovariectomized mice on a high fat diet developed extreme obesity and hyperleptinemia and moderate hyperinsulinemia compared to those on a standard diet. For the last 4 weeks, 17beta-estradiol-3-benzoate or its vehicle was administered subcutaneously in a 4-day cyclic regimen. Finally, leptin or saline was injected into the third ventricle, and food intake and body weight were measured for 36 h. In ovariectomized mice fed a standard diet, the decrease in food intake and body weight was significant and was pronounced in 17beta-estradiol-3-benzoate-supplemented mice. The response to centrally injected leptin in ovariectomized mice on a high fat diet was insignificant, whereas in 17beta-estradiol-3-benzoate-supplemented mice, the effect was significant, particularly with respect to body weight. We showed for the first time that central insensitivity to leptin in ovariectomized diet-induced obese mice was restored with 17beta-estradiol-3-benzoate supplementation, which also attenuated most of the parameters of metabolic syndrome. Only circulating adiponectin, a peripheral insulin sensitivity marker, was lowered following 17beta-estradiol-3-benzoate administration in both high fat and standard diet-fed ovariectomized mice, despite of decreased or unchanged glycemia, respectively.

[The influence of 6-months treatment with exenatide on type 2 diabetes mellitus compensation, anthropometric and biochemical parameters]

OBJECTIVES

Exenatide, a synthetic GLP-1 analogue, is a new antidiabetic agent from the group ofincretine mimetics coming into the daily clinical practice. In our study we evaluated the effect of 6-months treatment with exenatide on diabetes compensation, anthropometric and biochemical parameters in the patients with poorly controlled type 2 diabetes mellitus and obesity.

METHOD

We included 18 patients with poorly controlled diabetes (mean HbA1c 8.5 +/- 0.3%) treated with diet and peroral antidiabetic agents (4 patients were treated with insulin in the past). Exenatide was administered via subcutaneous injection twice daily for 6 months. Patients were examined after 1 month, when the dose ofexenatide was increased from 5 microg twice daily to 10 microg twice daily and after 3 and 6 months. We evaluated the diabetes compensation, biochemical parameters, body weight changes and side effects ofexenatide.

RESULTS

6-months exenatide treatment significant decreased body weight (baseline vs 6 month treatment 107.3 +/- 4.4 kg vs 103.7 +/- 4.6 kg, p = 0.02), BMI (36.7 +/- 1.2 kg/m2 vs 35.3 +/- 1.3 kg/m2, p = 0.01) a HbA1c (8.5 +/- 0.3% vs 7.4 +/- 0.4%, p = 0.04) and increased HDL-cholesterol (0.92 +/- 0.1 mmol/l vs 0.98 +/- 0.1 mmol/l, p = 0.02). Fasting glycemia tended to decline at the end of the study, but the difference did not reach the statistical significance. The area under the curve of glycemia levels after the standardized breakfast in the subgroup of 8 patients after the 6-months exenatide treatment was significantly lower when compared to baseline values (2,908 +/- 148 vs 2,093 +/- 194, p = 0.03). Concentrations of total and LDL-cholesterol and triglycerides did not change significantly. The most frequent side effects of exenatide treatments were transient anorexia and nausea (38.5%), dyspepsia and functional gastrointestinal discomfort (38.5%) and various neuropsychical symptoms (nervosity and insomnia - 30.8%). Most of the side effects disappeared during the treatment, none of these side effects was a reason for discontinuation of a treatment. 3 minor hypoglycemic episodes occured in patients simultaneously treated with derivates of sulfonylurea, but no serious hypoglycemia occured during the entire study.

CONCLUSION

Exenatide treatment in obese patients with poor diabetes control was accompanied by statistically significant decrease of body weight, improvement of diabetes control and increase in HDL-cholesterol.

Hepcidin expression in adipose tissue increases during cardiac surgery

Hepcidin, a key regulator of iron metabolism, plays a crucial role in the pathogenesis of anemia of chronic disease. Although it is produced mainly in the liver, its recently described expression in adipose tissue has been shown to be enhanced in massive obesity due to chronic low-grade inflammation. Our objective was to study the changes in hepcidin expression in adipose tissue during acute-phase reaction. We measured hepcidin mRNA expression from isolated subcutaneous and epicardial adipose tissue at the beginning and at the end of the surgery. The expression of mRNAs for hepcidin and other iron-related genes (transferrin receptor 1, divalent metal transporter 1, ferritin, ferroportin) were measured by real-time RT-PCR. Hepcidin expression significantly increased at the end of the surgery in subcutaneous but not in epicardial adipose tissue. Apart from the increased levels of cytokines, the parameters of iron metabolism showed typical inflammation-induced changes. We suggest that acute inflammatory changes could affect the regulation of hepcidin expression in subcutaneous adipose tissue and thus possibly contribute to inflammation-induced systemic changes of iron metabolism.

Plasma concentrations of fibroblast growth factors 21 and 19 in patients with Cushing's syndrome

The objective of this study was to measure plasma fibroblast growth factor 21 and 19 (FGF21 and FGF19) levels in patients with Cushing's syndrome (CS) and to compare it with those of lean control subjects (C) and patients with obesity (OB). Fourteen untreated patients with CS, 19 patients with OB and 36 controls were included in the study. Plasma FGF21 and FGF19 levels were measured by ELISA kits, other hormonal and biochemical parameters were measured by standard laboratory methods. Plasma FGF19 did not significantly differ among the studied groups. Plasma FGF21 levels were significantly higher in both CS and OB groups relative to C group but they did not differ between CS and OB groups. In a combined population of all three groups FGF21 levels positively correlated with BMI, waist circumference and percentage of total and truncal fat mass. Less prominent inverse relationship with these parameters was found for FGF19. Neither FGF21 nor FGF19 were significantly related to cortisol concentrations. Increased FGF21 concentrations in both patients with CS and OB relative to lean subjects suggest that excessive body fat and/or related metabolic abnormalities rather than direct effects of cortisol are responsible. In contrast neither obesity nor hypercortisolism significantly affected FGF19 concentrations.

Fibroblast growth factor 21: a novel metabolic regulator with potential therapeutic properties in obesity/type 2 diabetes mellitus

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.

[Comparison of various methods of body fat analysis in overweight and obese women]

INTRODUCTION

Body composition assessment and determination of the amount and distribution of body fat, respectively, form an essential part of the basic clinical assessment of an obese patient. However, there are no recommended methods to determine the amount of fat in obese population. The aim of our study was to compare the methods most frequently used to determine the amount of body fat in overweight and obese women in clinical practice (multi-frequency bio-electrical impedance analysis--BIA using the Bodystat, Omron and Tanita machines and the skinfold test using a calliper) with a reference method (DEXA). The study further aimed to compile prediction formulae enabling clinicians to calculate the percentage of body fat when using the available body fat measurement techniques.

METHODS

The study included 61 overweight and obese women (mean age 48.6 years +/- 13.9 years). Four practice-based body fat assessment methods were used - bioimpedance technique with tetra-polar electrode arrangement (Bodystat machine), bioimpedance technique with bi-pedal electrode arrangement (Tanita machine), hand-held bioimpedance technique (Omron machine) and the anthropometry assessment--the skinfold calliper technique. These methods were compared to the method considered as the reference--the whole body densinometry (DEXA).

RESULTS

The results obtained using the listed body fat assessment methods suggest that the resulting body fat measurements differ importantly depending on the method used. The highest correlation with DEXA was found for the Bodystat BIA (r = 0.9096, p < 0.001). Prediction formulae were constructed for a more accurate calculation of body fat content when using the techniques evaluated in the present study.

CONCLUSION

When the newly compiled formulae are employed, the body fat assessment obtained with any of the methods applied in the present study will approximate DEXA. The BIA techniques were found to be particularly precise. Therefore, further evaluation of these techniques is recommendable to support their use as methods for monitoring the efficacy of weight reduction programmes in overweight and obese patients.

The influence of obesity and different fat depots on adipose tissue gene expression and protein levels of cell adhesion molecules

Increased circulating adhesion molecules in patients with obesity play an important role in the development of endothelial dysfunction/atherosclerosis. The aim of this study was to assess the contribution of various fat depots to the production of adhesion molecules in obesity. 12 women with first and second degree of obesity, 13 women with third degree of obesity and 14 lean age-matched women were included into study. Circulating levels of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin were measured by Luminex kits. mRNA expression of ICAM-1, VCAM-1, E-selectin, monocyte chemoattractant protein-1 (MCP-1), and CD68 in subcutaneous (SAT) and visceral adipose tissue (VAT) was measured by RT-PCR; ICAM-1 and VCAM-1 protein levels by Luminex kits, normalized to protein content. Obesity increased ICAM-1 and VCAM-1 mRNA expression and protein levels and CD68 mRNA expression in VAT. Expression of E-selectin and MCP-1 did not significantly differ between groups. Expression of ICAM-1 and VCAM-1 positively correlated with expression of CD68 in both adipose depots. In VAT, ICAM-1 and VCAM-1 expression and protein levels positively correlated with BMI. Obesity was associated with increased adhesion molecules mRNA expression and protein levels in VAT, but not in SAT. Increased adhesion molecules production in visceral fat may provide a novel direct link between visceral adiposity and increased risk of cardiovascular complications.

The effect of pheochromocytoma treatment on subclinical inflammation and endocrine function of adipose tissue

The aim of our study was to evaluate the influence of surgical removal of pheochromocytoma on the endocrine function of adipose tissue and subclinical inflammation as measured by circulating C-reactive protein (CRP) levels. Eighteen patients with newly diagnosed pheochromocytoma were included into study. Anthropometric measures, biochemical parameters, serum CRP, leptin, adiponectin and resistin levels were measured at the time of diagnosis and six months after surgical removal of pheochromocytoma. Surgical removal of pheochromocytoma significantly increased body weight, decreased both systolic and diastolic blood pressure, fasting blood glucose and glycated hemoglobin levels. Serum CRP levels were decreased by 50 % six months after surgical removal of pheochromocytoma (0.49±0.12 vs. 0.23±0.05 mg/l, p<0.05) despite a significant increase in body weight. Serum leptin, adiponectin and resistin levels were not affected by the surgery. We conclude that increased body weight in patients after surgical removal of pheochromocytoma is accompanied by an attenuation of subclinical inflammation probably due to catecholamine normalization. We failed to demonstrate an involvement of the changes in circulating leptin, adiponectin or resistin levels in this process.

Serum visfatin levels in patients with anorexia nervosa and bulimia nervosa

Visfatin is an adipose tissue-derived hormone shown to correlate with visceral fat mass in patients with obesity. Its possible role in patients with different types of eating disorders is unknown. We measured fasting serum levels of visfatin and leptin and surrogate measures of insulin sensitivity in 10 untreated patients with anorexia nervosa (AN), 10 untreated patients with bulimia nervosa (BN) and 20 age-matched healthy women (C) to study the possible role of visfatin in these disorders. Patients with AN had severely decreased body mass index (BMI) and body fat content. BMI of BN group did not significantly differ from that of C group, whereas body fat content of BN group was significantly lower compared to C and higher compared to AN group, respectively. Serum glucose levels did not significantly differ among the groups studied, whereas serum insulin and leptin levels and HOMA index were significantly decreased in AN group relative to both C and BN group. In contrast, serum visfatin levels in both patients with AN and BN did not differ from those of C group. We conclude that circulating visfatin levels are not affected by the presence of chronic malnutrition in AN or binge/purge eating behavior in BN.

The endocrine profile of subcutaneous and visceral adipose tissue of obese patients

The aim of the present study was to evaluate the expression profile of genes potentially related to metabolic complications of obesity in the whole adipose tissue and isolated adipocytes from subcutaneous (SAT) and visceral adipose tissue (VAT) from 12 non-diabetic obese women and 12 lean women. Real-time polymerase chain reaction was used for expression analysis of 41 genes of interest and two housekeeping genes. We found increased expression of specific proinflammatory and adipogenic genes and reduced expression of specific lipogenic and insulin signaling pathway genes in obese relative to lean women with no preferable localization in SAT or VAT depot. The gene expression significantly differed between adipocytes and adipose tissue but both contributed to the proinflammatory profile in obesity. We conclude that both SAT and VAT exhibit alterations in the expression of specific genes possibly contributing to proinflammatory and insulin resistance state and consequently to metabolic complications of obesity.

Serum concentrations of adipocyte fatty acid binding protein in patients with anorexia nervosa

Serum adipocyte fatty acid-binding protein (FABP) concentrations are linked to human obesity and other features of metabolic syndrome. Whether FABP associates with metabolic alterations in chronic malnutrition is unknown. In the present study, we measured fasting serum levels of FABP, leptin, soluble leptin receptor, adiponectin, resistin, C-reactive protein (CRP), insulin, glucose, cholesterol and triglycerides in 19 patients with a restrictive type of anorexia nervosa (AN) and in 16 healthy age-matched control women (C). Body mass index, serum leptin, and CRP concentrations were significantly lower, while serum adiponectin and soluble leptin receptor levels were significantly higher in AN relative to C group. Serum insulin, glucose, cholesterol and triglyceride levels did not differ between the groups studied. Serum FABP levels were unchanged in patients with AN and were not related to any of parameters studied. We conclude that, in contrast to patients with obesity where FAPB is a prominent marker of metabolic alterations, chronic malnutrition in AN does not significantly affect its serum levels.

The role of ghrelin in the regulation of food intake in patients with obesity and anorexia nervosa

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.

[Pathogenesis of insulin resistance in different endocrinopathies]

Visceral obesity, insulin resistance and increased cardiovascular morbidity and mortality are strongly related. Development of visceral obesity and regulation of body fat distribution in general are influenced by many factors. This article is a summary of current knowledge about pathogenesis of insulin resistance in different endocrinopathies, particularly in the Cushing's syndrome and acromegaly, as they are both connected with the pathological conditions mentioned above.

Simultaneous decrease of plasma obestatin and ghrelin levels after a high-carbohydrate breakfast in healthy women

Ghrelin is a gut peptide produced mainly by stomach, well known to induce appetite stimulatory actions. Obestatin, a recently identified peptide derived from preproghrelin, was initially described to antagonize stimulatory effect of ghrelin on food intake. The postprandial response of obestatin and its relationship with ghrelin in humans remains unknown. We therefore investigated the postprandial response of obestatin and total ghrelin, acyl and desacyl ghrelin and neuropeptide Y (NPY) to a high-carbohydrate breakfast (1 604 kJ) in eight healthy women (age: 24.2+/-0.82 years; BMI 21.6+/-0.61 kg/m(2)). Blood samples were collected before the meal, and 30, 60, 90, 120 and 150 min after the breakfast consumption. Postprandial plasma obestatin concentrations significantly decreased compared with preprandial levels as well as total ghrelin concentrations and reached the lowest values 90 and 120 min after the meal consumption, respectively (p<0.05). Plasma acyl and desacyl ghrelin concentrations decreased after the breakfast and reached lowest values in 30 and 60 min, respectively (p<0.05). Plasma NPY concentrations were lower than preprandial levels 90 and 150 min after consuming breakfast (p<0.05). In conclusion, we demonstrated in healthy young women that plasma obestatin concentrations decrease similarly to ghrelin after a high-carbohydrate breakfast.

Serum adipocyte fatty acid binding protein levels in patients with type 2 diabetes mellitus and obesity: the influence of fenofibrate treatment

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-alpha 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-alpha 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 microg/l, T2DM before F: 55.6+/-5.7 microg/l, T2DM after F: 54.2+/-5.4 microg/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 MCR(glc)/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.

[The influence of very-low-calorie diet on soluble adhesion molecules and their gene expression in adipose tissue of obese women]

BACKGROUND

Adhesion molecules (AM) are proteins expressed on the endothelial surface that play an important role in development of endothelial dysfunction. Higher concentrations of AM were found in patients with atherosclerosis, obesity or type 2 diabetes mellitus. The aim of our study was to measure serum concentrations and gene expression of ICAM-1 (intercellular adhesion molecule 1), VCAM-1 (vascular adhesion molecule 1) and E-selectin in subcutaneous adipose tissue samples obtained by needle biopsy from obese women and healthy controls and to evaluate the effect of 3-weeks very-low-calorie diet (VLCD) on these parameters.

METHODS AND RESULTS

20 obese women (BMI 46.2 +/- 9.7 kg/m2) and 13 lean control women (BMI 23.8 +/- 2.3 kg/m2) were included into the study. Gene expression of AM in subcutaneous adipose tissue was measured using RT-PCR, serum AM levels were measured by multiplex immunoanalysis. At the baseline, serum E-selectin concentrations were higher in obese women compared to controls (24.4 +/- 2.3 vs. 15 +/- 1,5 ng/ml, p < 0,05). 3 weeks of VLCD significantly decreased BMI and serum E-selectin levels. Baseline mRNA expression of E-selectin, ICAM-1 and VCAM-1 in subcutaneous adipose tissue was lower in obese relative to lean women (p < 0.05). Weight reduction increased ICAM-1 and VCAM-1 gene expression (p < 0.05).

CONCLUSIONS

Our results suggest that the subcutaneous adipose tissue is not the major source of the studied soluble adhesion molecules in obese women and that the regulation of AM local gene expression in subcutaneous adipose tissue probably differs from its circulating levels.