BACKGROUND

Gestational diabetes mellitus (GDM) occurs in ∼<em>1</em>0-25% of pregnancies. <em>Nesfatin</em>-<em>1</em>, plays a role in carbohydrate metabolism by inhibiting glucagon secretion, besides has a glucose-dependent insulinotropic effect. Explanation of the GDM pathogenesis is important due to preventing gestational complications. We aimed to investigate relationship between GDM and <em>Nesfatin</em>-<em>1</em>.

METHODS

Seventy-nine pregnant subjects were randomly allocated to either GDM group (GDG, n = 38) or control group (CG, n = 4<em>1</em>). For GDM diagnosis, 50 and <em>1</em>00 g oral glucose tolerance test (OGTT) were used. <em>Nesfatin</em>-<em>1</em>, insulin and other parameters were measured for all subjects. The homeostasis model assessment-insulin resistance (HOMA-IR) was calculated.

RESULTS

<em>Nesfatin</em>-<em>1</em> was found lower and insulin was found higher in GDG than CG. Negative correlation has been founded between <em>Nesfatin</em>-<em>1</em> with weight, BMI, fasting glucose, serum glucose level at first hour of the 50 g OGTT and HOMA-IR.

CONCLUSIONS

In this study, patients with GDM had lower <em>Nesfatin</em>-<em>1</em> levels than without GDM. Therefore, when the <em>Nesfatin</em>-<em>1</em> effects on the GDM pathogenesis is clear, it may be contributed to diagnosis and treatment of the GDM.

Mitochondrial oxidative and thermogenic functions in brown and beige adipose tissues modulate rates of energy expenditure. It is unclear, however, how beige or white adipose tissue contributes to brown fat thermogenic function or compensates for partial deficiencies in this tissue and protects against obesity. Here, we show that the transcription factor Yin Yang <em>1</em> (YY<em>1</em>) in brown adipose tissue activates the canonical thermogenic and uncoupling gene expression program. In contrast, YY<em>1</em> represses a series of secreted proteins, including fibroblast growth factor 2<em>1</em> (FGF2<em>1</em>), bone morphogenetic protein 8b (BMP8b), growth differentiation factor <em>1</em>5 (GDF<em>1</em>5), angiopoietin-like 6 (Angptl6), neuromedin B, and <em>nesfatin</em>, linked to energy expenditure. Despite substantial decreases in mitochondrial thermogenic proteins in brown fat, mice lacking YY<em>1</em> in this tissue are strongly protected against diet-induced obesity and exhibit increased energy expenditure and oxygen consumption in beige and white fat depots. The increased expression of secreted proteins correlates with elevation of energy expenditure and promotion of beige and white fat activation. These results indicate that YY<em>1</em> in brown adipose tissue controls antagonistic gene expression programs associated with energy balance and maintenance of body weight.

Hunger and satiety are regulated in a complex fashion by a few food intake stimulatory (orexigenic) and a multitude of inhibitory (anorexigenic) factors produced in the periphery (mainly in the gastrointestinal tract) or directly in the brain. Within the brain, the hypothalamus plays a pivotal role as a production site of food intake regulatory factors. Importantly, this site integrates peripheral and central signaling factors to orchestrate food intake and in the long term body weight. Our knowledge on these regulatory pathways is not static but rather rapidly changing as new factors as well as up- and downstream signaling pathways of already known transmitters are uncovered. Hypothalamic nucleobindin2 (NUCB2), the precursor of <em>nesfatin</em>-<em>1</em>, was first described in 2006 and <em>nesfatin</em>-<em>1</em> found to be a novel anorexigenic modulator of food intake and body weight. The initial report stimulated several groups to investigate the biological actions of <em>nesfatin</em>-<em>1</em> and subsequent studies delineated the underlying brain mechanisms involved in its food reducing effect. Of interest was the demonstration that NUCB2 also exerts its anorexigenic action in the paraventricular nucleus of the hypothalamus and is regulated at this site by changes in metabolic status with a diurnal rhythm inversely related to that of feeding in rats. The present review describes the current state-of-knowledge on central <em>nesfatin</em>-<em>1</em>'s effects on food intake and body weight and highlights important missing links regarding cellular signaling mechanisms involved in <em>nesfatin</em>-<em>1</em>'s action.

<em>Nesfatin</em>-<em>1</em> is well-established to induce an anorexigenic effect. Recently, <em>nesfatin</em>-<em>1</em>30-59, was identified as active core of full length <em>nesfatin</em>-<em>1</em><em>1</em>-82 in mice, while its role in rats remains unclear. Therefore, we investigated the effects of <em>nesfatin</em>-<em>1</em>30-59 injected intracerebroventricularly (icv) on the food intake microstructure in rats. To assess whether the effect was also mediated peripherally we injected <em>nesfatin</em>-<em>1</em>30-59 intraperitoneally (ip). Since obesity affects the signaling of various food intake-regulatory peptides we investigated the effects of <em>nesfatin</em>-<em>1</em>30-59 under conditions of diet-induced obesity (DIO). Male Sprague-Dawley rats fed ad libitum with standard diet were icv cannulated and injected with vehicle (5 μl ddH2O) or <em>nesfatin</em>-<em>1</em>30-59 at 0.37, <em>1</em>.<em>1</em>, and 3.3 μg (0.<em>1</em>, 0.3, 0.9 nmol/rat) and the food intake microstructure assessed using a food intake monitoring system. Next, naïve rats were injected ip with vehicle (300 μl saline) or <em>nesfatin</em>-<em>1</em>30-59 (8.<em>1</em>, 24.3, 72.9 nmol/kg). Lastly, rats were fed a high fat diet for <em>1</em>0 weeks and those developing DIO were icv cannulated. <em>Nesfatin</em>-<em>1</em> (0.9 nmol/rat) or vehicle (5 μl ddH2O) was injected icv and the food intake microstructure assessed. In rats fed standard diet, <em>nesfatin</em>-<em>1</em>30-59 caused a dose-dependent reduction of dark phase food intake reaching significance at 0.9 nmol/rat in the period of 4-8 h post injection (-29%) with the strongest reduction during the fifth hour (-75%), an effect detectable for 24 h (-<em>1</em>2%, p < 0.05 vs. vehicle). The anorexigenic effect of <em>nesfatin</em>-<em>1</em>30-59 was due to a reduction in meal size (-44%, p < 0.05), while meal frequency was not altered compared to vehicle. In contrast to icv injection, <em>nesfatin</em>-<em>1</em>30-59 injected ip in up to 30-fold higher doses did not alter food intake. In DIO rats fed high fat diet, <em>nesfatin</em>-<em>1</em>30-59 injected icv reduced food intake in the third hour post injection (-7<em>1</em>%), an effect due to a reduced meal frequency (-27%, p < 0.05), while meal size was not altered. Taken together, <em>nesfatin</em>-<em>1</em>30-59 is the active core of <em>nesfatin</em>-<em>1</em><em>1</em>-82 and acts centrally to reduce food intake in rats. The anorexigenic effect depends on the metabolic condition with increased satiation (reduction in meal size) under normal weight conditions, while in DIO rats satiety (reduction in meal frequency) is induced.

The novel satiety factor <em>nesfatin</em>-<em>1</em> and its precursor NUCB2 are the neuropeptides widely expressed in the central nervous system. <em>Nesfatin</em>-<em>1</em>/NUCB2 is also localized in peripheral tissues and regulates the glucose and energy metabolism on multiple processes. <em>Nesfatin</em>-<em>1</em> potentiates both insulin release from pancreatic β-cells and insulin action in liver, contributing to energy storage. Furthermore, <em>nesfatin</em>-<em>1</em>/NUCB2 regulates adipocyte differentiation. The polymorphism of the NUCB2 gene is associated with obesity. Thus, <em>nesfatin</em>- <em>1</em>/NUCB2 plays a role in integrating feeding, glucose homeostasis, and energy storage/expenditure. Dysfunction of expression, secretion and/or action of <em>nesfatin</em>-<em>1</em>/NUCB2 might be involved in the type 2 diabetes, obesity and metabolic syndrome. <em>Nesfatin</em>-<em>1</em>/NUCB2 and its regulatory processes may provide novel targets for treating associated diseases of the metabolic syndrome. Here, we review the by now published studies on <em>nesfatin</em>-<em>1</em>/NUCB2 localization and action in islets and discuss the physiological and pathophysiological roles of the <em>nesfatin</em>-<em>1</em>/NUCB2 in glucose and energy metabolism.

<em>Nesfatin</em>-<em>1</em> is an 82 amino acid secreted peptide encoded in the precursor, nucleobindin-2 (NUCB2). It is an insulinotropic anorexigen abundantly expressed in the stomach and hypothalamus. Post-prandial insulin secretion is predominantly regulated by incretins glucagon-like peptide <em>1</em> (GLP-<em>1</em>) and glucose-dependent insulinotropic polypeptide (GIP). <em>Nesfatin</em>-<em>1</em> was previously reported to modulate GLP-<em>1</em> and GIP secretion in vitro in an enteroendocrine (STC-<em>1</em>) cell line. Intestine is a source of additional hormones including cholecystokinin (CCK) and peptide YY (PYY) that regulate metabolism. We hypothesized that <em>nesfatin</em>-<em>1</em> modulates CCK and PYY secretion. Immunofluorescence histochemistry showed NUCB2/<em>nesfatin</em>-<em>1</em> co-localizing CCK and PYY in the intestinal mucosa of mice. Static incubation of STC-<em>1</em> cells with <em>nesfatin</em>-<em>1</em> upregulated both CCK mRNA expression (<em>1</em> and <em>1</em>0 nM) and secretion (0.<em>1</em>, <em>1</em> and <em>1</em>0 nM) at <em>1</em> h post-incubation. In contrast, <em>nesfatin</em>-<em>1</em> treatment for <em>1</em> h downregulated PYY mRNA expression (all doses tested) and secretion (0.0<em>1</em> and 0.<em>1</em> nM) in STC-<em>1</em> cells. Continuous infusion of <em>nesfatin</em>-<em>1</em> using osmotic mini-pumps for <em>1</em>2 h upregulated CCK mRNA expression in large intestine, and downregulated PYY mRNA expression in both large and small intestines of male C57BL/6J mice. In these tissues, Western blot analysis found a corresponding increase in CCK and a decrease in PYY content. Collectively, we provide new information on the cell specific localization of NUCB2/<em>nesfatin</em>-<em>1</em> in the intestinal mucosa, and a novel function for <em>nesfatin</em>-<em>1</em> in modulating intestinal CCK and PYY expression and secretion in mice.

The aim of this study was to compare the levels of <em>nesfatin</em>-<em>1</em> in healthy subjects with those in prediabetic and diabetic patients who have different glucose tolerance levels. Overall, <em>1</em>00 subjects were divided into 5 groups healthy control (C), impaired fasting glycemia (IFG), impaired glucose tolerance (IGT), metabolic syndrome (MS) and type 2 diabetes mellitus, (Type 2 DM). Glycated hemoglobin (HbA<em>1</em>c) assessed the glycemic control. Homeostasis model assessment of insulin resistance (HOMA-IR) was determined using computer analyses. <em>Nesfatin</em>-<em>1</em> levels were measured using ELISA method. IFG and IGT (prediabetic groups) from MS and Type 2 DM (diabetic groups) differed significantly in HOMA-IR. The <em>nesfatin</em>-<em>1</em> levels were lower, although not statistically significant, in IFG (0.937+/-0.03 ng/ml, p=0.07) and IGT (<em>1</em>.039+/-0.06 ng/ml, p=0.5) groups compared to healthy subjects (<em>1</em>.094+/-0.07 ng/ml). However, the <em>nesfatin</em>-<em>1</em> levels were lower in patients with Type 2 DM (0.867+/-0.02 ng/ml, p=0.007) and MS (0.885+/-0.0<em>1</em> ng/ml, p=0.0<em>1</em>) compared to healthy subjects. <em>Nesfatin</em>-<em>1</em> levels were significantly lower in diabetic patients compared to healthy subjects. This study supports the role of insulin resistance in decreased <em>nesfatin</em>-<em>1</em> levels in patients with Type 2 DM and MS.

Phoenixin-<em>1</em>4 (PNX) is a newly identified peptide co-expressed in the hypothalamus with the anorexic and cardioactive <em>Nesfatin</em>-<em>1</em>. Like <em>Nesfatin</em>-<em>1</em>, PNX is able to cross the blood-brain barrier and this suggests a role in peripheral modulation. Preliminary mass spectrography data indicate that, in addition to the hypothalamus, PNX is present in the mammalian heart. This study aimed to quantify PNX expression in the rat heart, and to evaluate whether the peptide influences the myocardial function under basal condition and in the presence of ischemia/reperfusion (I/R). By ELISA the presence of PNX was detected in both hypothalamus and heart. In plasma of normal, but not of obese rats, the peptide concentrations increased after meal. Exposure of the isolated and Langendorff perfused rat heart to exogenous PNX induces a reduction of contractility and relaxation, without effects on coronary pressure and heart rate. As revealed by immunoblotting, these effects were accompanied by an increase of Erk<em>1</em>/2, Akt and eNOS phosphorylation. PNX (EC50 dose), administered after ischemia, induced post-conditioning-like cardioprotection. This was revealed by a smaller infarct size and a better systolic recovery with respect to those detected on hearts exposed to I/R alone. The peptide also activates the cardioprotective RISK and SAFE cascades and inhibits apoptosis. These effects were also observed in the heart of obese rats. Our data provide a first evidence on the peripheral activity of PNX and on its direct cardiomodulatory and cardioprotective role under both normal conditions and in the presence of metabolic disorders.

The hypothalamic neuropeptide <em>Nesfatin</em>-<em>1</em> is present in both mammals and teleosts in which it elicits anorexigenic effects. In mammals, <em>Nesfatin</em>-<em>1</em> acts on the heart by inducing negative inotropism and lusitropism, and cardioprotection against ischemic damages. We evaluated whether in teleosts, <em>Nesfatin</em>-<em>1</em> also influences cardiac performance. In the goldfish (Carassius auratus), mature, fully processed <em>Nesfatin</em>-<em>1</em> was detected in brain, gills, intestine and skeletal muscle, but not in the cardiac ventricle. However, on the isolated and perfused working goldfish heart, exogenous <em>Nesfatin</em>-<em>1</em> induced a positive inotropic effect, revealed by a dose-dependent increase of stroke volume (SV) and stroke work (SW). Positive inotropism was abolished by inhibition of adenylate cyclase (AC; MDL<em>1</em>23330A) and cAMP-dependent kinase (PKA; KT5720), suggesting a cAMP/PKA-mediated pathway. This was confirmed by the increased cAMP concentrations revealed by ELISA on <em>Nesfatin</em>-<em>1</em>-treated hearts. Perfusion with Diltiazem, Thapsigargin and PD98059 showed the involvement of L-type calcium channels, SERCA2a pumps and ERK<em>1</em>/2, respectively. The role of ERK<em>1</em>/2 and phospholamban in <em>Nesfatin</em>-<em>1</em>-induced cardiostimulation was supported by Western blotting analysis. In conclusion, this is the first report showing that in teleosts, <em>Nesfatin</em>-<em>1</em> potentiates mechanical cardiac performance, strongly supporting the evolutionary importance of the peptide in the control of the cardiac function of vertebrates.

Postoperative ileus (POI) develops after abdominal surgery irrespective of the site of surgery. When prolonged, POI can lead to longer hospitalization times and higher healthcare costs. Moreover, it is associated with complaints for the patient. In order to develop new strategies to treat this condition, a deeper understanding of the pathophysiology of the POI is necessary. This review will focus on brain peptides (ghrelin, <em>nesfatin</em>-<em>1</em>, somatostatin, corticotropin-releasing factor, thyrotropin-releasing hormone and calcitonin gene-related peptide) involved in the mediation of POI and the possible modulation of these pathways to shorten the time of POI. Lastly, the role of vagal signaling or chewing gum as potential treatment strategies of alleviating symptoms of POI is discussed.

Stress has become an integral part of human life and organisms are being constantly subjected to stress and the ability to cope with such stress is a crucial determinant of health and disease. Neuropeptides (bioactive peptides) play a crucial role in mediating different effects of acute and chronic stress. Some of these neuropeptides including oxytocin, urocortins, neuropeptide Y (NPY), neuropeptide S, cocaine and amphetamine regulated transcript, endorphins, enkephalins, ghrelin and thyrotropin-releasing hormone primarily attenuate stress and act as anxiolytic. On the other hand, neuropeptides including corticotropin releasing hormone, vasopressin, dynorphin, angiotensin, <em>nesfatin</em>-<em>1</em>, orexin and cholecystokinin primarily tend to promote stress related anxiety behavior. However, these neuropeptide tend to produce different actions depending on the type of receptors, the nature and intensity of the stressor. For example, NPY may exhibit anxiolytic effects by activating NPY<em>1</em> and Y5 receptors, while pro-depressive effects are produced through NPY2 and Y4 receptors. Galanin may produce 'prodepressive' effects by activating its Gal <em>1</em> receptors and exert 'antidepressant' effects through Gal 2 receptors. The present review describes different neuropeptides as therapeutic targets to attenuate stress-induced behavioral and neuroendocrinological effects.

<em>Nesfatin</em>-<em>1</em>, a product of the nucleobindin 2 (NUCB2) gene, purportedly plays important roles in whole-body energy homeostasis. Experiments were conducted to determine how NUCB2 expression in fat depots may be controlled in the pig and to test the hypothesis that <em>nesfatin</em>-<em>1</em> regulates appetite and LH secretion in the gilt. Prepubertal gilts were used to study expression of NUCB2 in fat and the effects of intracerebroventricular (i.c.v.) injection of <em>nesfatin</em>-<em>1</em> on food intake and pituitary hormone secretion. Growing pigs (gilts and barrows at 22 wk of age, n = <em>1</em>,<em>1</em>45) or sexually mature gilts (n = 439) were used to test association of SNP in the NUCB2 gene with growth traits. The expression of NUCB2 was similar for subcutaneous fat compared with perirenal fat. An i.c.v. injection of the melanocortin-4 receptor agonist [Nle⁴, d-Phe⁷]-α-melanocyte-stimulating hormone did not alter expression of NUCB2 mRNA in the hypothalamus but reduced (P = 0.056) NUCB2 mRNA expression in subcutaneous fat. Short-term (7 d) submaintenance feeding reduced (P < 0.05) BW and did not alter expression of mRNA for NUCB2, visfatin, or leptin but increased (P < 0.05) expression of adiponectin mRNA in fat. Central injection of <em>nesfatin</em>-<em>1</em> suppressed (P < 0.00<em>1</em>) feed intake. Secretion of LH was greater (P < 0.0<em>1</em>) after i.c.v. injection of <em>nesfatin</em>-<em>1</em> than after saline. Single nucleotide polymorphisms in the porcine NUCB2 gene were not associated with adiposity of growing pigs or age at puberty in gilts but were associated (P < 0.05) with BW at puberty. These data indicate that NUCB2 is expressed in fat depots of the pig and that the level of expression is sensitive to stimulation of appetite-regulating pathways in the hypothalamus. It is confirmed herein that <em>nesfatin</em>-<em>1</em> can regulate appetite in the pig and affect the gonadotropic axis of the prepubertal pig. Association of SNP in the porcine NUCB2 gene with BW at puberty suggests that regulation of appetite by <em>nesfatin</em>-<em>1</em> in the pig affects growth, which may have important consequences for adult phenotypes.

The current study investigated the effects of <em>nesfatin</em>-<em>1</em> in the hypothalamic paraventricular nucleus (PVN) on gastric motility and the regulation of the lateral hypothalamic area (LHA). Using single unit recordings in the PVN, we show that <em>nesfatin</em>-<em>1</em> inhibited the majority of the gastric distention (GD)-excitatory neurons and excited more than half of the GD-inhibitory (GD-I) neurons in the PVN, which were weakened by oxytocin receptor antagonist H4928. Gastric motility experiments showed that administration of <em>nesfatin</em>-<em>1</em> in the PVN decreased gastric motility, which was also partly prevented by H4928. The <em>nesfatin</em>-<em>1</em> concentration producing a half-maximal response (EC50) in the PVN was lower than the value in the dorsomedial hypothalamic nucleus, while <em>nesfatin</em>-<em>1</em> in the reuniens thalamic nucleus had no effect on gastric motility. Retrograde tracing and immunofluorescent staining showed that nucleobindin-2/<em>nesfatin</em>-<em>1</em> and fluorogold double-labeled neurons were observed in the LHA. Electrical LHA stimulation changed the firing rate of GD-responsive neurons in the PVN. Pre-administration of an anti- nucleobindin-2/<em>nesfatin</em>-<em>1</em> antibody in the PVN strengthened gastric motility and decreased the discharging of the GD-I neurons induced by electrical stimulation of the LHA. These results demonstrate that <em>nesfatin</em>-<em>1</em> in the PVN could serve as an inhibitory factor to inhibit gastric motility, which might be regulated by the LHA.

BACKGROUND

<em>Nesfatin</em>/Nucleobindin-2 (Nesf/NUCB2), a precursor of <em>nesfatin</em>-<em>1</em>, an anorexigenic protein, is ubiquitously expressed in peripheral tissues in addition to the hypothalamus. However, the role of intracellular Nesf/NUCB2 has not been established in the periphery.

METHODS

Nesf/NUCB2-transgenic (Tg) mice were generated, and chronological changes of body weight and daily food intake were measured in Nesf/NUCB2-Tg mice fed normal laboratory chow or 45% high-fat diet (HFD). In addition, changes of metabolic markers were evaluated in those mice.

RESULTS

No differences were observed in daily food intake and body weight between Nesf/NUCB2-Tg mice (n=<em>1</em><em>1</em>) and their non-Tg littermates (n=<em>1</em><em>1</em>) fed normal chow. Nesf/NUCB2-Tg mice showed increased mRNA expression of oxytocin and corticotropin-releasing hormone and decreased mRNA expression of cocaine- and amphetamine-related transcript in the hypothalamus. Nesf/NUCB2-Tg mice fed 45% HFD (n=6) showed significantly higher increase in body weight than their non-Tg littermates fed the same diet (n=8); however, no difference was observed in daily food intake between these two groups. Further, Nesf/NUCB2-Tg mice fed 45% HFD showed a significant increase in the weight of the liver, subcutaneous fat, and brown adipose tissue and decrease in the expression of uncoupling protein-<em>1</em> in the subcutaneous fat. Blood glucose levels of Nesf/NUCB2-Tg mice fed 45% HFD were not different from those of their non-Tg littermates fed the same diet. Insulin levels of these Tg mice were significantly higher than those of their non-Tg littermates. Histological analysis showed marked fat deposition in the hepatocytes surrounding the hepatic central veins in Nesf/NUCB2-Tg mice fed 45% HFD.

CONCLUSIONS

Overexpression of Nesf/NUCB2 did not change food intake, but increased body weight only in Nesf/NUCB2-Tg mice fed HFD. The results of this study indicate that Nesf/NUCB2 was involved in the development of insulin resistance and fat deposition in the liver, independent of the modulation of energy intake.

<em>Nesfatin</em>-<em>1</em> is a novel 82-amino acid anorectic peptide. Previous studies of <em>nesfatin</em>-<em>1</em> have focused on hypothalamic and brainstem circuits implicated in feeding regulation. Recently, <em>nesfatin</em>-<em>1</em> expression was also reported in the nucleus accumbens (NAc), amygdaloid nucleus and insular cortex of mice, areas that are related to the control of reward behavior. Therefore, it is possible that <em>nesfatin</em>-<em>1</em> might also inhibit food intake via central reward circuits. Using electrophysiology and electrochemical and behavioral tests, we investigated the effect of <em>nesfatin</em>-<em>1</em> on the dopaminergic reward pathway between the ventral tegmental area (VTA) and the NAc. Our results showed that injection of <em>nesfatin</em>-<em>1</em> into the VTA significantly inhibited dark-phase cumulative food intake in mice. The excitability of VTA dopaminergic neurons was inhibited by <em>nesfatin</em>-<em>1</em>. In addition, <em>nesfatin</em>-<em>1</em> decreased dopamine release in the NAc. Therefore, we concluded that <em>nesfatin</em>-<em>1</em> acts on dopaminergic neurons, and these effects might contribute to the decrease of food intake that results from the injection of <em>nesfatin</em>-<em>1</em> into the VTA.

OBJECTIVE

Type 2 diabetes mellitus (T2DM) and prediabetes (pre-DM) are associated with changes in levels of metabolic markers. The main aim of this study is to compare the levels of omentin, irisin, endothelin-<em>1</em>, <em>nesfatin</em>, hepatocyte growth factor (HGF), fibroblast growth factor, and oxytocin (OXT) between normoglycemic and pre-DM/T2DM obese Jordanian patients.

METHODS

One hundred and ninety-eight adult Jordanian subjects were recruited. Demographic data and clinical parameters were collected. The serum levels of biomarkers were measured by enzymatic assay procedure.

RESULTS

Compared to normoglycemic (95 subjects), pre-DM/T2DM (<em>1</em>03 subjects) displayed higher HGF (ng/ml) = 78.8 (7<em>1</em>.4-<em>1</em>04) versus 55.9 (45.3-66.6), p < 0.000<em>1</em>; and <em>nesfatin</em> (ng/ml) = 0.5 (0.4-0.7) versus 0.2 (0.<em>1</em>-0.4), p < 0.000<em>1</em>; betatrophin (ng/ml) = <em>1</em>.2 (0.8-<em>1</em>.6) versus 0.22 (0.<em>1</em>5-0.4<em>1</em>), p < 0.000<em>1</em>. On the other hand, they had lower levels of omentin (ng/ml) = 2.<em>1</em> (0.9-3.3) versus 3.6 (2.0-6.4), p < 0.000<em>1</em>, irisin (ng/ml) = <em>1</em><em>1</em>3.7 (88.9-<em>1</em>42.9) versus <em>1</em>32.6 (<em>1</em><em>1</em>0.7-<em>1</em>47.8), p < 0.000<em>1</em>; and oxytocin (pg/ml) = <em>1</em>077.9 (667.3-<em>1</em>506.0) versus 2<em>1</em>80.<em>1</em> (<em>1</em>464.5-2795.6), p < 0.000<em>1</em>; respectively. In comparison, FGF-2<em>1</em> (ng/ml) = 0.3 (0.2-0.5) versus 0.2 (0.<em>1</em>-0.4), and endothelin (pg/ml) = 2.7 (<em>1</em>.3-5.2) versus 2.8 (<em>1</em>.6-5.6) did not differ between the two groups (p>> 0.05).

CONCLUSIONS

In the present study, patients with pre-DM and T2DM have higher serum levels of metabolic HGF, nesfatin, and betatrophin and lower levels of omentin, irisin, and OXT. Future longitudinal and interventional studies are required to confirm the utility of these markers as novel progression or therapeutic targets in the pharmacotherapy of diabetes.

OBJECTIVE

The study was designed to determine metformin effects on meal pattern, gastric emptying, energy expenditure, and to identify metformin-sensitive neurons and their phenotype.

METHODS

This study was performed on C57BL/6J and obese/diabetic (db/db) mice. Metformin (300 mg/kg) was administered by oral gavage. Food intake, meal pattern, oxygen consumption (VO2 ), and carbon dioxide production (VCO2 ) were obtained using an Oxylet Physiocage System. Gastric emptying assay and real-time RT-PCR from dorsal vagal complex extracts were also performed. C-Fos expression was used as a marker of neuronal activation. Phenotypic characterization of activated neurons was performed using either proopiomelanocortin (POMC)-Tau-Topaz GFP transgenic mice or NUCB2/<em>nesfatin</em>-<em>1</em> and tyrosine hydroxylase (TH) labeling.

RESULTS

Acute per os metformin treatment slowed down gastric emptying, reduced meal size, but not meal number in a leptin-independent manner, and transiently decreased energy expenditure in a leptin-dependent manner. Metformin specifically activated central circuitry within the brainstem, independently of vagal afferents. Finally, while POMC neurons seemed sparsely activated, we report that a high proportion of the c-Fos positive cells were nesfatinergic neurons, some of which coexpressing TH.

CONCLUSIONS

Altogether, these results show that metformin modifies satiation by activating brainstem circuitry and suggest that NUCB2/<em>nesfatin</em>-<em>1</em> could be involved in this metformin effect.

<em>Nesfatin</em>-<em>1</em>, an 82 amino acid gastric peptide, is involved in regulation of food uptake and in multiple metabolic activities. Whether <em>nesfatin</em>-<em>1</em> modulates the differentiation and lipid metabolism of brown adipocytes remains unknown. In the present study, we found that <em>nesfatin</em>-<em>1</em> mRNA and protein were detectable in isolated brown adipocytes and gradually decreased during differentiation (95% CI 0.6057 to <em>1</em>.034, p = 0.000<em>1</em>). The decrease in <em>nesfatin</em>-<em>1</em> was associated with a significant reduction in p-S6. Exposure to <em>nesfatin</em>-<em>1</em> promoted differentiation of brown adipocytes as revealed by a significant increase in UCP<em>1</em> mRNA (p = 0.03) and lipolysis-related ATGL mRNA (p = 0.04). <em>Nesfatin</em>-<em>1</em> attenuated phosphorylation of S6K and S6 during brown adipocyte differentiation. Activation of mTOR by leucine or deletion of TSC<em>1</em> decreased expression of brown adipocyte-related genes UCP<em>1</em>, UCP3, PGC<em>1</em>α and PRDM<em>1</em>6, as well as COX8B and ATP5B. Both leucine and TSC<em>1</em> deletion blocked <em>nesfatin</em>-<em>1</em>-induced up-regulation of UCP<em>1</em>, PGC<em>1</em>α, COX8B and ATP5B in differentiated brown adipocytes. In conclusion, <em>nesfatin</em>-<em>1</em> promotes the differentiation of brown adipocytes likely through the mTOR dependent mechanism.

Exercise is recognized as an effective method of weight management and short-term appetite regulation tool. The effect of different exercise intensities on appetite regulation hormones in healthy overweight participants has not been intensively studied. The aim of this study was to examine the influence of exercise at individual anaerobic threshold (IAT) and maximal fat oxidation (Fatmax) intensities on the <em>nesfatin</em>-<em>1</em> response and metabolic health biomarkers in overweight men. Nine healthy overweight males (age, 23.<em>1</em> ± <em>1</em>.<em>1</em> years) volunteered in this study in a counterbalanced order. Blood samples were obtained before, immediately after, and following the first 45 min of recovery for measuring plasma variables. There was significant decrease in plasma levels of <em>nesfatin</em>-<em>1</em> and leptin after exercise at the IAT intensity which remained lower than baseline following 45 min of recovery. However, <em>nesfatin</em>-<em>1</em> and leptin levels did not change significantly in any time courses of Fatmax intensity (P>> 0.09). Plasma interleukin-6 (IL-6) concentration increased during exercise in both intensities (P < 0.05), whereas changes in free fatty acids (FFAs) and epinephrine concentrations were significant only at the IAT. In addition, a significant correlation was found among <em>nesfatin</em>-<em>1</em> levels with insulin (r = 0.39, P < 0.05) and glucose (r = 0.4<em>1</em>, P < 0.05) at basal and in response to exercise. These results indicate that IAT has a greater exercise-induced appetite regulation effect compared with Fat(max). Based on these data, the intensity of exercise may have an important role in changes of <em>nesfatin</em>-<em>1</em>, leptin, FFA, and epinephrine concentrations even though this was not the case for IL-6 and insulin resistance.

OBJECTIVE

To determine the expression levels of gastrointestinal <em>nesfatin</em>-<em>1</em> in ventromedial hypothalamic nucleus (VMH)-lesioned (obese) and ventrolateral hypothalamic nucleus (VLH)-lesioned (lean) rats that exhibit an imbalance in their energy metabolism and gastric mobility.

METHODS

Male Wistar rats were randomly divided into a VMH-lesioned group, a VLH-lesioned group, and their respective sham-operated groups. The animals had free access to food and water, and their diets and weights were monitored after surgery. Reverse transcription-polymerase chain reaction and immunostaining were used to analyse the levels of NUCB2 mRNA and <em>nesfatin</em>-<em>1</em> immunoreactive (IR) cells in the stomach, duodenum, small intestine, and colon, respectively. Gastric emptying was also assessed using a modified phenol red-methylcellulose recovery method.

RESULTS

The VMH-lesioned rats fed normal chow exhibited markedly greater food intake and body weight gain, whereas the VLH-lesioned rats exhibited markedly lower food intake and body weight gain. NUCB2/<em>nesfatin</em>-<em>1</em> IR cells were localised in the lower third and middle portion of the gastric mucosal gland and in the submucous layer of the enteric tract. Compared with their respective controls, gastric emptying was enhanced in the VMH-lesioned rats (85.94% ± 2.27%), whereas the VLH lesions exhibited inhibitory effects on gastric emptying (29.<em>1</em>2% ± <em>1</em>.62%). In the VMH-lesioned rats, the levels of NUCB2 mRNA and <em>nesfatin</em>-<em>1</em> protein were significantly increased in the stomach and duodenum and reduced in the small intestine. In addition, the levels of NUCB2 mRNA and <em>nesfatin</em>-<em>1</em> protein in the VLH-lesioned rats were decreased in the stomach, duodenum, and small intestine.

CONCLUSIONS

Our study demonstrated that <em>nesfatin</em>-<em>1</em> level in the stomach and duodenum is positively correlated with body mass. Additionally, there is a positive relationship between gastric emptying and body mass. The results of this study indicate that gastrointestinal <em>nesfatin</em>-<em>1</em> may play a significant role in gastric mobility and energy homeostasis.

The aim of this study was to characterize the mechanism by which peripheral <em>nesfatin</em>-<em>1</em> regulates hepatic lipid metabolism. Continuous peripheral infusion of <em>nesfatin</em>-<em>1</em> reduced adiposity and plasma levels of triglyceride and cholesterol. In mice fed high fat diet, peripheral <em>nesfatin</em>-<em>1</em> significantly decreased hepatic steatosis measured by triglyceride content and oil red staining area and diameter. These alterations were associated with a significant reduction in lipogenesis-related transcriptional factors PPARγ and SREBP<em>1</em>, as well as rate-limited enzyme genes such as acaca, fasn, gpam, dgat<em>1</em> and dgat2. In primary hepatocytes, <em>nesfatin</em>-<em>1</em> inhibited both basal and oleic acid stimulated triglyceride accumulation, which was accompanied by a decrement in lipogenesis-related genes and an increase in β-oxidation-related genes. In cultured hepatocytes, <em>nesfatin</em>-<em>1</em> increased levels of AMPK phosphorylation. Inhibition of AMPK by compound C blocked the reduction of triglyceride content elicited by <em>nesfatin</em>-<em>1</em>. Our studies demonstrate that <em>nesfatin</em>-<em>1</em> attenuates lipid accumulation in hepatocytes by an AMPK-dependent mechanism.

OBJECTIVE

The association of obstructive sleep apnea syndrome (OSAS) and metabolic syndrome (MS) has been demonstrated in studies and in recent years; the effect of OSAS on insulin resistance independent of the level of obesity is being investigated. <em>Nesfatin</em>-<em>1</em> is a newly defined 82 amino acid protein with a precursor molecule of NUCB2 (nucleobindin 2). <em>Nesfatin</em>-<em>1</em> is not only essential in regulation of food ingestion but also important in regulation of some brain functions, autonomic regulation, stress, mental state, and paradoxical sleep. We aimed to evaluate the relationship between OSAS and MS and the MS dependent or independent effect of <em>Nesfatin</em>-<em>1</em> on this relationship.

METHODS

Patients admitted with clinical signs of OSAS are included. Patients are divided into three groups based on Apnea-Hypopnea Index (AHI) on Polysomnography (PSG) as mild, moderate, and severe OSAS. A total of 59 patients were included the control patients. Several OSAS parameters and laboratory findings which are and are not MS dependent are compared. <em>Nesfatin</em>-<em>1</em> levels are evaluated in all OSAS patients with and without MS.

RESULTS

There were significantly more males in all groups (p = 0.007). There was no significant difference between groups in terms of <em>Nesfatin</em>-<em>1</em> levels. <em>Nesfatin</em>-<em>1</em> levels were significantly lower in MS group compared to non-MS group (p = 0.02<em>1</em>).

CONCLUSIONS

<em>Nesfatin</em>-<em>1</em> which is known to play a role in the pathophysiology of insulin resistance can be a beneficial target in developing new therapeutic targets for treatment of patients with obesity without any toxic effects in the future.

<em>Nesfatin</em>-<em>1</em>, which is derived from the NEFA/nucleobindin 2 (NUCB2) precursor, was recently identified as an anorexigenic peptide that is produced in several tissues including the hypothalamus. Currently, no data exist regarding the regulation of NUCB2/<em>nesfatin</em>-<em>1</em> production in peripheral tissues, such as gastric mucosa and adipose tissue, through different periods of development. The aim of the present work was to study the variations on circulating levels, mRNA expression and tissue content in gastric mucosa and adipose tissue of NUCB2/<em>nesfatin</em>-<em>1</em> with age and specially in two clue periods of maturation, weaning and puberty. The weaning period affected NUCB2/<em>nesfatin</em>-<em>1</em> production in gastric tissue. The testosterone changes associated with the initiation of puberty regulated NUCB2/<em>nesfatin</em>-<em>1</em> production via adipose tissue and gastric NUCB2/<em>nesfatin</em>-<em>1</em> production. In conclusion, the production of NUCB2/<em>nesfatin</em>-<em>1</em> by the stomach and adipose tissue fluctuates with age to regulate energy homeostasis during different states of development.

<em>Nesfatin</em> is a peptide secreted by peripheral tissues, central and peripheral nervous system. It is involved in the regulation of homeostasis. Although the effects of <em>nesfatin</em>-<em>1</em> on nutrition have been studied widely in the literature, the mechanisms of <em>nesfatin</em>-<em>1</em> action and also relations with other physiological parameters are still not clarified well. We aimed to investigate the effect of peripheral chronic <em>nesfatin</em>-<em>1</em> application on blood pressure regulation in normal and in rats exposed to restraint immobilization stress. In our study, three month-old male Wistar rats were used. Rats were divided into 4 groups as Control, Stress, Control+<em>Nesfatin</em>-<em>1</em>, <em>Nesfatin</em>-<em>1</em>+Stress. Angiotensinogen, angiotensin converting enzyme 2, angiotensin II, endothelin-<em>1</em>, endothelial nitric oxide synthase, aldosterone, cortisol, <em>nesfatin</em>-<em>1</em> levels were determined in plasma samples by ELISA. Our results have shown that chronic peripheral <em>nesfatin</em>-<em>1</em> administration increases blood pressure in normal and in rats exposed to chronic restraint stress. Effect of <em>nesfatin</em>-<em>1</em> on circulating level of angiotensinogen, angiotensin converting enzyme 2, angiotensin II, endothelin-<em>1</em>, endothelial nitric oxide synthase, aldosterone and cortisol has been identified. We can conclude that elevated high blood pressure after chronic peripheral <em>nesfatin</em>-<em>1</em> administration in rats exposed to chronic restraint stress may be related to decreased plasma level of endothelial nitric oxide synthase concentration.