Evidence for a role of endogenous nesfatin-1 in the control of water drinking

Fluid transitions

Water is critical for survival and thirst is a powerful way of ensuring that fluid levels remain in balance. Overconsumption, however, can have deleterious effects, therefore optimization requires a need to balance the drive for water with the satiation of that water drive. This review will highlight our current understanding of how thirst is both generated and quenched, with particular focus on the roles of angiotensin II, glucagon like-peptide 1, and estradiol in turning on and off the thirst drive. Our understanding of the roles these bioregulators play has benefited from modern behavioral analyses, which have improved the time resolution of intake measures, allowing for attention to the details of the patterns within a bout of intake. This has led to behavioral interpretation in ways that are helpful in understanding the many controls of water intake and has expanded our understanding beyond the dichotomy that something which increases water intake is simply a "stimulator" while something that decreases water intake is simply a "satiety" factor. Synthesizing the available information, we describe a framework in which thirst is driven directly by perturbations in fluid intake and indirectly modified by several bioregulators. This allows us to better highlight areas that are in need of additional attention to form a more comprehensive understanding of how the system transitions between states of thirst and satiety.

Nesfatin-1 and nesfatin-1-like peptide attenuate hepatocyte lipid accumulation and nucleobindin-1 disruption modulates lipid metabolic pathways

Nesfatin-1 (NESF-1) has been shown to modulate lipid metabolism. We have identified a nesfatin-1-like-peptide (NLP) processed from a related precursor nucleobindin 1 (NUCB1). Here we determined if NLP, like NESF-1, regulates lipid accumulation in vitro, and tested if the disruption of nucb1 gene affects hepatic lipid metabolism genes in mice. Hepatocytes (HepG2/C3A cells) express NLP and NESF-1 and both peptides significantly reduced lipogenic enzyme mRNAs and enhanced beta-oxidation enzyme mRNAs. Lipid contents in oleic acid induced HepG2/C3A cells were attenuated by NESF-1 and NLP. The inhibitory effect on cellular lipid content was blocked by compound C, an inhibitor of AMPK. The disruption of nucb1 gene affected lipid metabolism-related enzyme mRNAs, endogenous nucb2 mRNA and AMPK phosphorylation. The lipid-lowering effects identified here highlights the potential of nucleobindins and peptides processed from them to address lipid disorders, and its possible benefits in metabolic disease management.

Zinc Supplementation Improved Neuropeptide Y, Nesfatin-1, Leptin, C-reactive protein, and HOMA-IR of Diet-Induced Obese Rats

Obesity is a mild chronic inflammation that causes many metabolic diseases. It was aimed to investigate some parameters affective on the energy metabolism by adding zinc (Zn, ZnSO4) to drinking water of diet-induced obese rats. Five-week aged, male Sprague Dawley rats divided into as control group, consuming standard rat diet, and high-fat diet (HFD) group. After obesity induced by feeding HFD for 8 weeks, the obese rats were divided into Zn-supplemented obese group (HFD + obese + Zn; 150 mg Zn/L (for 6 weeks), 235 mg Zn/L (7th week), 250 mg Zn/L (8th week) in drinking water) and obese group (HFD + obese). Mean body weight, serum concentrations of C-reactive protein, neuropeptide-Y, leptin, insulin fasting blood glucose, and HOMA-IR were statistically decreased by given Zn in HFD + obese + Zn group compared to HFD + obese rats. It was observed that the total cholesterol, LDL, and HDL cholesterol levels of HFD + obese + Zn group became closer to the control group level, and Zn supplementation caused a statistically significant decrease in cholesterol profile than HFD + obese rats. Also, increased mean serum nesfatin-1 level, an effective protein for the formation of satiety, was analyzed in HFD + obese + Zn group when compared to HFD + obese ones. Serum triglyceride concentration tended to decrease with the effect of Zn in obese rats. In conclusion, it can be said that oral use of Zn could improve energy balance and prevent the occurrence of metabolic diseases related to obesity depending on the anti-inflammatory effect of Zn.

The relationship between Vaspin, Nesfatin-1 plasma levels and presence of fragmented QRS with the severity of coronary atherosclerosis

PURPOSE

Despite continuous efforts to address classical risk factors for atherosclerosis, the battle to control the disease is far from over and atherosclerosis is still a major factor in all-cause mortality. To investigate the relations between early diagnosis and severity of coronary atherosclerosis we examined vaspin and nesfatin-1 levels, and the presence of fragmented QRS (fQRS) in admission electrocardiograms.

MATERIALS AND METHODS

We divided 168 patients into asymptomatic control (18%), <50% coronary artery stenosis (28%), >50% stenosis (31%) and myocardial infarction (MI) (23%) groups. Patients were also evaluated in anatomically significant (>50%stenosis ​+ ​MI) and non-significant atherosclerosis (control+<50%stenosis) groups. Vaspin and nesfatin-1 levels were measured using ELISA methods.

RESULTS

Vaspin in MI and >50% stenosis groups was lower than in other groups (p ​< ​0.001). Nesfatin-1 in MI and >50% stenosis groups was lower only than in <50%stenosis group (p0.007). The presence of fQRS was higher in MI and >50% stenosis groups than other groups (p ​< ​0.001). In the anatomically significant atherosclerosis group, vaspin, nesfatin-1 and left ventricular ejection fraction (LVEF) values were lower while Gensini score and the presence of fQRS were higher (for all p ​< ​0.001). Lower vaspin levels and fQRS were related to in-hospital mortality (p ​< ​0.001 and p ​= ​0.02,respectively). Logistic regression analysis showed that male gender, diabetes mellitus, smoking, family history, lower LVEF, lower vaspin and fQRS were defined as independent risk factors for anatomically significant atherosclerosis (p ​= ​0.001).

CONCLUSIONS

Our results indicate that low vaspin and fQRS were found to be novel independent risk factors for anatomically significant atherosclerosis and were predictors of mortality.

The Actions of Centrally Administered Nesfatin-1 on Emesis, Feeding, and Locomotor Activity in Suncus murinus (House Musk Shrew)

Nesfatin-1 is an anorectic peptide expressed in both peripheral tissues and brain areas involved in the regulation of feeding, emotion and emesis. The aim of the present study is to characterize the distribution of NUCB2/nesfatin-1 in Suncus murinus and to investigate the actions of nesfatin-1 to affect gastrointestinal contractility, emesis, food and water intake, and locomotor activity. The deduced amino acid sequence of S. murinus nesfatin-1 using in silico cloning showed high homology with humans and rodents. NUCB2 mRNA was detected throughout the entire brain and in the gastrointestinal tract, including the stomach and gut. Western blot analysis and immunohistochemistry confirmed the expression of nesfatin-1 protein in these regions. The NUCB2 mRNA levels in the hypothalamus, hippocampus and brainstem were significantly decreased, whereas that in the striatum were increased after 24 h starvation compared to ad libitum-fed animals (p &lt; 0.05). In in vitro studies, nesfatin-1 (0.3–1,000 pM) failed to contract or relax the isolated gastric antrum and intestinal segments. In conscious, freely moving animals, intracerebroventricular administration of nesfatin-1 (1–50 pmol) induced emesis (p &lt; 0.05) and suppressed 6-h cumulative food intake (p &lt; 0.05), without affecting the latency to feeding. Nesfatin-1 (25 pmol, i.c.v.) decreased 24-h cumulative food and water intake by 28.3 and 35.4%, respectively (p &lt; 0.01). No significant differences in locomotor activity were observed. In conclusion, NUCB2/nesfatin-1 might be a potent regulator of feeding and emesis in S. murinus. Further studies are required to elucidate the mechanism of actions of this peptide as a mediator linking the brainstem NUCB2/nesfatin-1 to forebrain system.

Nucleobindin-derived nesfatin-1 and nesfatin-1-like peptide stimulate pro-opiomelanocortin synthesis in murine AtT-20 corticotrophs through the cAMP/PKA/CREB signaling pathway

Nucleobindin (NUCB)-derived peptides, nesfatin-1 (NES-1) and nesfatin-1-like peptide (NLP) have several physiological roles in vertebrates. While NES-1 is implicated in stress, whether NUCB1/NLP and NUCB2/NES-1 have any effect on proopiomelanocortin (POMC) remains unknown. The main aim of this study was to determine if NES-1 and/or NLP affect POMC synthesis in mouse corticotrophs. Immunocytochemistry was employed to target NUCB colocalization with POMC in immortalized mouse tumoral corticotrophs (AtT-20 cells). The ability of NES-1 and NLP to modulate POMC mRNA and protein in AtT-20 cells was assessed by qPCR and Western blot, respectively. Moreover, cell-signaling molecules mediating the effect of NES-1 and NLP on POMC synthesis in mouse tumoral corticotrophs were studied using pharmacological blockers. Mouse tumoral corticotrophs showed immunoreactivity for both NUCB1/NLP and NUCB2/NES-1. Both NES-1 and NLP exerted a stimulatory effect on POMC transcript abundance and protein expression in a dose- and time-dependent manner. This effect was comparable to corticotropin-releasing factor (CRF, positive control) stimulation of POMC. Incubation of mouse tumoral corticotrophs with NES-1 or NLP upregulated the phosphorylation of protein kinase A (PKA) and cAMP-response element-binding protein (CREB). The stimulatory effect of these peptides on POMC transcript abundance and protein expression was blocked by the PKA inhibitor, H89, and an adenylate cyclase inhibitor, 2',3'-dideoxyadenosine (DDA). These pharmacological studies indicate that NES-1 and NLP act through the cAMP/PKA/CREB cellular pathway to stimulate POMC synthesis. Our results provide molecular evidence to support a stimulatory role for nucleobindin-derived peptides on POMC synthesis from corticotrophs. Collectively, this research indicates that corticotrophs produce NUCBs, and the encoded peptides NES-1 and NLP could elicit a direct action to stimulate the pituitary stress hormone. This stimulatory effect is mediated by an uncharacterized G protein-coupled receptor (GPCR) that utilizes the cAMP/PKA/CREB pathway.

Chemogenetic activation of endogenous arginine vasopressin exerts anorexigenic effects via central nesfatin-1/NucB2 pathway

We examined whether the chemogenetic activation of endogenous arginine vasopressin (AVP) affects central nesfatin-1/NucB2 neurons, using a transgenic rat line that was previously generated. Saline (1 mL/kg) or clozapine-N-oxide (CNO, 1 mg/mL/kg), an agonist for hM3Dq, was subcutaneously administered in adult male AVP-hM3Dq-mCherry transgenic rats (300-370 g). Food and water intake were significantly suppressed after subcutaneous (s.c.) injection of CNO, with aberrant circadian rhythmicity. The percentages of Fos expression in nesfatin-1/NucB2-immunoreactive neurons were significantly increased in the hypothalamus and brainstem at 120 min after s.c. injection of CNO. Suppressed food intake that was induced by chemogenetic activation of endogenous AVP was ablated after intracerebroventricularly administered nesfatin-1/NucB2-neutralizing antibody in comparison with vehicle, without any alteration of water intake nor circadian rhythmicity. These results suggest that chemogenetic activation of endogenous AVP affects, at least in part, central nesfatin-1/NucB2 neurons and may exert anorexigenic effects in the transgenic rats.

Endogenous NUCB2/Nesfatin-1 Regulates Energy Homeostasis Under Physiological Conditions in Male Rats

Nesfatin-1 is the proteolytic cleavage product of Nucleobindin 2, which is expressed both in a number of brain nuclei (e. g., the paraventricular nucleus of the hypothalamus) and peripheral tissues. While Nucleobindin 2 acts as a calcium binding protein, nesfatin-1 was shown to affect energy homeostasis upon central nervous administration by decreasing food intake and increasing thermogenesis. In turn, Nucleobindin 2 mRNA expression is downregulated in starvation and upregulated in the satiated state. Still, knowledge about the physiological role of endogenous Nucleobindin 2/nesfatin-1 in the control of energy homeostasis is limited and since its receptor has not yet been identified, rendering pharmacological blockade impossible. To overcome this obstacle, we tested and successfully established an antibody-based experimental model to antagonize the action of nesfatin-1. This model was then employed to investigate the physiological role of endogenous Nucleobindin 2/nesfatin-1. To this end, we applied nesfatin-1 antibody into the paraventricular nucleus of satiated rats to antagonize the presumably high endogenous Nucleobindin 2/nesfatin-1 levels in this feeding condition. In these animals, nesfatin-1 antibody administration led to a significant decrease in thermogenesis, demonstrating the important role of endogenous Nucleobindin 2/nesfatin-1in the regulation of energy expenditure. Additionally, food and water intake were significantly increased, confirming and complementing previous findings. Moreover, neuropeptide Y was identified as a major downstream target of endogenous Nucleobindin 2/nesfatin-1.

Nesfatin-1 decreases the motivational and rewarding value of food

Homeostatic and hedonic pathways distinctly interact to control food intake. Dysregulations of circuitries controlling hedonic feeding may disrupt homeostatic mechanisms and lead to eating disorders. The anorexigenic peptides nucleobindin-2 (NUCB2)/nesfatin-1 may be involved in the interaction of these pathways. The endogenous levels of this peptide are regulated by the feeding state, with reduced levels following fasting and normalized by refeeding. The fasting state is associated with biochemical and behavioral adaptations ultimately leading to enhanced sensitization of reward circuitries towards food reward. Although NUCB2/nesfatin-1 is expressed in reward-related brain areas, its role in regulating motivation and preference for nutrients has not yet been investigated. We here report that both dopamine and GABA neurons express NUCB2/nesfatin-1 in the VTA. Ex vivo electrophysiological recordings show that nesfatin-1 hyperpolarizes dopamine, but not GABA, neurons of the VTA by inducing an outward potassium current. In vivo, central administration of nesfatin-1 reduces motivation for food reward in a high-effort condition, sucrose intake and preference. We next adopted a 2-bottle choice procedure, whereby the reward value of sucrose was compared with that of a reference stimulus (sucralose + optogenetic stimulation of VTA dopamine neurons) and found that nesfatin-1 fully abolishes the fasting-induced increase in the reward value of sucrose. These findings indicate that nesfatin-1 reduces energy intake by negatively modulating dopaminergic neuron activity and, in turn, hedonic aspects of food intake. Since nesfatin-1´s actions are preserved in conditions of leptin resistance, the present findings render the NUCB2/nesfatin-1 system an appealing target for the development of novel therapeutical treatments towards obesity.

NUCB2/nesfatin-1 - Inhibitory effects on food intake, body weight and metabolism

Since its discovery in 2006 by Oh-I and colleagues, NUCB2/nesfatin-1 encoded by nucleobindin-2 (NUCB2) has drawn sustained attention as reflected in over 500 publications. Among those, more than half focused on the alterations of food intake, body weight and metabolism (glucose, fat) induced by nesfatin-1 and/or NUCB2/nesfatin-1. In the current review we discuss the existing literature focusing on NUCB2/nesfatin-1's influence on food intake, body weight and glucose as well as fat metabolism and highlight gaps in knowledge.

Nesfatin-1 in cardiovascular orchestration: From bench to bedside

Since the discovery of Nesfatin-1 in 2006, intensive research was finalized to further and deeper investigate the precise physiological functions of the peptide at both central and peripheral levels, rapidly enriching the knowledge regarding this intriguing molecule. Nesfatin-1 is a hypothalamic peptide generated via the post-translational processing of its precursor Nucleobindin 2, a protein supposed to play a role in many biological processes thanks to its ability to bind calcium and to interact with different intracellular proteins. Nesfatin-1 is mainly known for its anorexic properties, but it also controls water intake and glucose homeostasis. Recent experimental evidences describe the peptide as a possible direct/indirect orchestrator of central and peripheral cardiovascular control. A specific Nesfatin-1 receptor still remains to be identified although numerous studies suggest that the peptide activates extra- and intracellular regulatory pathways by involving several putative binding sites. The present paper was designed to systematically review the latest findings about Nesfatin-1, focusing on its cardiovascular regulatory properties under normal and physiopathological conditions. The hope is to provide the conceptual basis to consider Nesfatin-1 not only as a pleiotropic neuroendocrine molecule, but also as a homeostatic modulator of the cardiovascular function and with a crucial role in cardiovascular diseases.

Can Nesfatin-1 Predict Hypertension in Obese Children?

Objective

The prevalence of childhood obesity is increasing and leads to co-morbidities such as hypertension. However, it is still not clear why some obese individuals are hypertensive and others not. Nesfatin-1 is a recently discovered anorexigenic peptide which also has effects on blood pressure (BP). Our aim was to evaluate the relationship between obesity-related hypertension and Nesfatin-1.

Methods

This cross-sectional study comprised 87 obese children. The patients were divided into two groups; hypertensive (n=30) and normotensive (n=57) obese. The American Academy of Pediatrics guidelines were used to diagnose hypertension. Blood samples were collected after 12 hours of fasting to investigate Nesfatin-1 concentrations. We also evaluated serum trace elements in addition to the routine blood tests.

Results

Body mass index (BMI), weight and serum Nesfatin-1 concentrations were higher in the hypertensive group (p=0.002, p=0.001, and p=0.007, respectively). There was no difference between serum zinc levels, but Copper (Cu) levels were significantly lower in the hypertensive group (p=0.248, p=0.007, respectively). There were positive correlations between BP and BMI and weight Z-scores and a negative correlation with Cu. The optimal cut-off value of Nesfatin-1 to predict hypertension was found to be >1.8 ng/mL, with a specificity of 71.9% and a sensitivity of 96.7% [area under the curve=0.703, 95% confidence interval (CI): 0.577-0.809; p=0.002]. In multiple logistic regression analysis Nesfatin-1 [Odds ratio (OR)=1.103, 95% CI: 1.039-1.171; p=0.001], Cu (OR=0.947, 95% CI: 0.915-0.979; p=0.001) and BMI for age Z-score (OR=56.277, 95% CI: 5.791-546.907; p=0.001) still remained significant predictors of hypertension.

Conclusion

Nesfatin-1 levels are higher and are an independent predictor of hypertension in obese subjects.

Expression and function of nesfatin-1 are altered by stage of the estrous cycle

Nesfatin-1 is a peptide derived from the nucleobindin 2 (Nucb2) precursor protein that has been shown to exert potent effects on appetite and cardiovascular function in male animals. Sex hormones modulate the expression of Nucb2 in several species, including goldfish, mouse, and rat, and human studies have revealed differential expression based on male or female sex. We therefore hypothesized that the ability of nesfatin-1 to increase mean arterial pressure (MAP) would be influenced by stage of the estrous cycle. Indeed, we found that in cycling female Sprague-Dawley rats, nesfatin-1 induced an increase in MAP on diestrus, when both estrogen and progesterone levels are low but not on proestrus or estrus. The effect of nesfatin-1 on MAP was dependent on functional central melanocortin receptors, because the nesfatin-1-induced increase in MAP was abolished by pretreatment with the melanocortin 3/4 receptor antagonist, SHU9119. We previously reported that nesfatin-1 inhibited angiotensin II-induced water drinking in male rats but found no effect of nesfatin-1 in females in diestrus. However, nesfatin-1 enhanced angiotensin II-induced elevations in MAP in females in diestrus but had no effect on males. Finally, in agreement with previous reports, the expression of Nucb2 mRNA in hypothalamus was significantly reduced in female rats in proestrus compared with rats in diestrus. From these data we conclude that the function and expression of nesfatin-1 are modulated by sex hormone status. Further studies are required to determine the contributions of chromosomal sex and individual sex hormones to the cardiovascular effects of nesfatin-1.

Centrally administered kisspeptin suppresses feeding via nesfatin-1 and oxytocin in male rats

Kisspeptin (KP), known as a hypothalamic neuropeptide, plays a critical role in the regulation of not only reproduction but also food intake. The anorectic neuropeptides, nesfatin-1 and oxytocin (OXT), are expressed in central nervous system, particulaly in various hypothalamic nuclei, and peripheral tissue. We examined the effects of the intracerebroventricular (icv) administration of KP-10 on feeding and nesfatin-1-immunoreactive (ir) or OXT-ir neurons in the rat hypothalamus, using Fos double immunohistochemistry in male rats. Cumulative food intake was remarkably decreased 0.5-3 h after icv administration of KP-10 (6.0 μg) compared to the vehicle treated and the KP-10 (3.8 μg) treated group. The icv administration of KP-10 significantly increased the number of nesfatin-1-ir neurons expressing Fos in the supraoptic nucleus (SON), paraventricular nucleus (PVN), arcuate nucleus (ARC), dorsal raphe nucleus, locus coeruleus, and nucleus tractus solitarius. The decreased food intake induced by KP-10 was significantly attenuated by pretreatment with the icv administration of antisense RNA against nucleobindin-2. After icv administration of KP-10, the percentages of OXT-ir neurons expressing FOS were remarkably higher in the SON and PVN than for vehicle treatment. The KP-10-induced anorexia was partially abolished by pretreatment with OXT receptor antagonist (OXTR-A). The percentage of nesfatin-1-ir neurons expressing Fos-ir in the ARC was also decreased by OXTR-A pretreatment. These results indicate that central administration of KP-10 activates nesfatin-1- and OXT neurons, and may play an important role in the suppression of feeding in male rats.

Nucleobindin-2/Nesfatin-1 in the Human Hypothalamus Is Reduced in Obese Subjects and Colocalizes with Oxytocin, Vasopressin, Melanin-Concentrating Hormone, and Cocaine- and Amphetamine-Regulated Transcript

BACKGROUND/AIMS

Nesfatin-1, processed from nucleobindin-2 (NUCB2), is a potent anorexigenic peptide being expressed in rodent hypothalamic nuclei and involved in the regulation of feeding behavior and body weight in animals. The present study aimed to investigate NUCB2/nesfatin-1 protein expression in the human hypothalamus as well as its correlation with body weight.

METHODS

Sections of hypothalamus and adjacent cholinergic basal forebrain nuclei, including the nucleus basalis of Meynert (NBM) and the diagonal band of Broca (DBB), from 25 autopsy cases (17 males, 8 females; 8 lean, 9 overweight, 8 obese) were examined using immunohistochemistry and double immunofluorescence labeling.

RESULTS

Prominent NUCB2/nesfatin-1 immunoexpression was detected in supraoptic, paraventricular, and infundibular nuclei, lateral hypothalamic area (LHA)/perifornical region, and NBM/DBB. NUCB2/nesfatin-1 was found to extensively colocalize with (a) oxytocin and vasopressin in paraventricular and supraoptic nuclei, (b) melanin-concentrating hormone in the LHA, and (c) cocaine- and amphetamine-regulated transcript in infundibular and paraventricular nuclei and LHA. Interestingly, in the LHA, NUCB2/nesfatin-1 protein expression was significantly decreased in obese, compared with lean (p < 0.01) and overweight (p < 0.05) subjects.

CONCLUSIONS

The findings of the present study are suggestive of a potential role for NUCB2/nesfatin-1 as an integral regulator of food intake and energy homeostasis in the human hypothalamus. In the LHA, an appetite- and reward-related brain area, reduced NUCB2/nesfatin-1 immunoexpression may contribute to dysregulation of homeostatic and/or hedonic feeding behavior and obesity. NUCB2/nesfatin-1 localization in NBM/DBB might imply its participation in the neuronal circuitry controlling cognitive influences on food intake and give impetus towards unraveling additional biological actions of NUCB2/nesfatin-1 in human neuronal networks.

SERUM NESFATIN-1 LEVEL IN HEALTHY SUBJECTS WITH WEIGHT-RELATED ABNORMALITIES AND NEWLY DIAGNOSED PATIENTS WITH TYPE 2 DIABETES MELLITUS; A CASE-CONTROL STUDY

Context

Nesfatin-1 is a novel peptide with both central and peripheral anorexigenic regulatory properties. Besides its effects on food intake, few studies have suggested a possible role for this peptide in the pathogenesis of diabetes mellitus type 2.

Objective

To compare serum levels of nesfatin-1 between healthy, normal-weight persons and three groups including healthy underweight, healthy obese and diabetic subjects.

Design

Prospective, case-control study, performed between January 2015 and January 2016.

Subjects and Methods

Fasting levels in serum nesfatin-1 were measured in 30 healthy, normal-weight individuals (controls), 30 healthy underweight persons, 30 healthy obese persons, and 30 patients with newly diagnosed diabetes type 2 using standard enzyme-linked immunosorbent assay (ELISA) kits.

Results

The mean serum nesfatin-1 level was significantly higher in controls (2.61 ng/mL) compared to that in obese (1.13 ng/mL) and diabetic (0.99 ng/mL) patients; and significantly lower than that in the underweight group (3.50 ng/mL). The obese and diabetic groups were comparable in this regard. No significant association was found between serum nesfatin-1 level and age, sex, or body mass index.

Conclusions

Serum nesfatin-1 is possibly associated with weight-related abnormalities in otherwise healthy subjects and diabetes type 2. Obesity and diabetes type 2 may share a common pathologic point in this regard.

Phoenixin: Expression at different ovarian development stages and effects on genes ralated to reproduction in spotted scat, Scatophagus argus

Phoenixin (Pnx), a recently discovered neuropeptide, has been implicated in reproduction. Pnx mainly exists in two active isoforms, phoenixin-14 (Pnx-14) and phoenixin-20 (Pnx-20). However, little is known about the functions of Pnx in teleosts. To determine the roles of Pnx in the regulation of reproduction in Scatophagus argus, the physiological characterization of the Pnx was analyzed. During ovary development, the expression of pnx in phase IV was higher than in phase II and III in the hypothalamus. In the pituitary, pnx expression was highest in phase IV, moderate in phase III, and lowest in phase II. When hypothalamus and pituitary fragments were cultured in vitro with Pnx-14 and Pnx-20 (10 nM and 100 nM) for 6 h, the expression of GnRHR (gonadotropin releasing hormone receptor), lh (luteinizing hormone) and fsh (follicular stimulating hormone) in the pituitary increased significantly, except GnRH (gonadotropin releasing hormone) in the hypothalamus. Similarly, the expression of GnRHR, lh and fsh in the pituitary increased significantly after injecting S. argus with Pnx-14 and Pnx-20 (10 ng/g and 100 ng/g body weight (bw)), except GnRHR and fsh treated with 10 ng/gbw Pnx-20 in the pituitary and GnRHs in the hypothalamus. These results indicate that Pnx may not only stimulate the reproduction of the S. argus through the hypothalamic-pituitary-gonadal (HPG) axis, but also directly through the pituitary.

Current Understanding of the Role of Nesfatin-1

Nesfatin-1 was discovered in 2006 and implicated in the regulation of food intake. Subsequently, its widespread central and peripheral distribution gave rise to additional effects. Indeed, a multitude of actions were described, including modulation of gastrointestinal functions, glucose and lipid metabolism, thermogenesis, mediation of anxiety and depression, as well as cardiovascular and reproductive functions. Recent years have witnessed a great increase in our knowledge of these effects and their underlying mechanisms, which will be discussed in the present review. Lastly, gaps in knowledge will be highlighted to foster further studies.

[Nutrient Sensing and Anorexia via Neuropeptides]

 Various neuropeptides play an essential role in the nutrient sensing mechanism and related homeostasis. Nesfatin-1 is a newly identified neuropeptide having anorectic activity, and nesfatin-1-containing neurons are widely distributed in the brain, including the hypothalamus and brain stem. Our previous study showed that dehydration-induced anorectic effects are mediated via the central nesfatin-1 pathway in rats. Our recent studies have also shown that peripheral anorectic peptides (cholecystokinin-8, glucagon-like peptide-1, and leptin) and an antineoplastic agent (cisplatin) caused inhibition of feeding via the central nesfatin-1 pathway in rats. Nesfatin-1-containing neurons in the central nervous system, in particular the hypothalamus and the brain stem, may mediate peripheral nutrient signals and regulate feeding behavior.

Involvement of central nesfatin-1 neurons on oxytocin-induced feeding suppression in rats

Peripheral anorectic hormones, such as peptide YY (PYY) and oxytocin (OXT), suppress food intake. A newly identified anorectic neuropeptide, nesfatin-1, is synthesized in both peripheral tissue and the central nervous system, particularly by various nuclei in the hypothalamus and brainstem. Here, we examined the effects of intraperitoneal (ip) administration of PYY_3-36, OXT, and OXT analog, on nesfatin-1-immunoreactive (ir) neurons in the rat hypothalamus and brainstem, using Fos double fluorescence-immunohistochemistry. The ip administration of OXT and OXT analog significantly increased the number of nesfatin-1-ir neurons expressing Fos-ir in the paraventricular nucleus, the arcuate nucleus, and the nucleus tractus solitarius, but not in the supraoptic nucleus, the lateral hypothalamic area, and the area postrema. No differences in the percentage of nesfatin-1-ir neurons expressing Fos in the nuclei of the hypothalamus and brainstem were observed, between rats treated with vehicle or those treated with PYY_3-36. The decreased food intake, induced by OXT and OXT analog, was attenuated significantly by pretreatment with intracerebroventricular administration of antisense nesfatin-1. These results suggested that nesfatin-1-expressing neurons in the hypothalamus and brainstem may play a role in sensing the peripheral level of OXT and its suppression of feeding in rats.

Alterations of circulating NUCB2/nesfatin-1 during short term therapeutic improvement of anxiety in obese inpatients

In addition to its anorexigenic properties in the neuroendocrine regulation of hunger and satiety, mounting evidence indicates a role for NUCB2/nesfatin-1 in the regulation of emotional stress responses which seems to occur in a sex-specific way. In the present study, we investigated the association of NUCB2/nesfatin-1 plasma levels with anxiety, depressiveness and perceived stress in obese men and women and their alterations during inpatient treatment. We expected a decrease of NUCB2/nesfatin-1 levels in female and an increase in male patients reporting a relevant alleviation of anxiety. We analyzed 69 inpatients (44 female, 25 male; body mass index, mean: 50.2±9.5kg/m², range: 31.8-76.5kg/m²; mean age: 45.0±12.4years) hospitalized due to morbid obesity with mental (not necessarily anxiety disorders) and somatic comorbidities. NUCB2/nesfatin-1 plasma levels were measured by ELISA. Anxiety (GAD-7), depressiveness (PHQ-9) and perceived stress (PSQ-20) were concurrently determined as patient-reported outcomes. All measurements were carried out at the initiation of and during inpatient treatment when a clinically meaningful improvement of anxiety was achieved (≥5 points on GAD-7) or missed (±1 point). NUCB2/nesfatin-1 was positively correlated with anxiety scores in women at the beginning of (r=0.411; p=0.006) and during (r=0.301; p=0.047) inpatient treatment. In men, a significant negative correlation was observed following treatment (r=-0.469; p=0.018), while at the outset of treatment only a trend was observed (r=-0.381; p=0.059). Unexpectedly, neither women (n=19; at beginning vs. during treatment; 0.49±1.00ng/ml vs. 0.38±0.72ng/ml; p=0.687) nor men (n=9; 0.17±0.31ng/ml vs. 0.19±0.36ng/ml; p=0.427) who improved in anxiety scores (p<0.001) displayed significant changes of NUCB2/nesfatin-1 plasma levels, although the direction of change was as expected with a decrease in women (-23.3%) and an increase in men (+12.4%). In addition, the change of NUCB2/nesfatin-1 was not explained by the course of anxiety (women: p=0.587; men: p=0.373). In conclusion, women and men showed an inverse association between NUCB2/nesfatin-1 and anxiety with a positive correlation in women and a negative correlation in men (although this correlation was not statistically significant in men at the beginning of treatment). However, no significant change of NUCB2/nesfatin-1 following improvement of anxiety has been observed. This might be due to the short observation interval, or due to too small anxiety improvements associated with too low baseline anxiety levels.

Serum Cytokine Levels are related to Nesfatin-1/NUCB2 Expression in the Implantation Sites of Spontaneous Abortion Model of CBA/j × DBA/2 Mice

The process of spontaneous abortion involves a complex mechanism with various cytokines, growth factors, and hormones during the pregnancy. However, the mechanism underlying spontaneous abortion by pro- and anti-inflammatory cytokines in the serum during the pregnancy is not fully understood. Therefore, the purpose of this study was to examine the relationship between the serum levels of pro- and anti-inflammatory cytokines and spontaneous abortion using the CBA/j × DBA/2 mouse model. Serum levels of pro-inflammatory cytokines, such as IFN-γ, IL-1α and TNF-α were not increased in abortion model mice, but anti-inflammatory cytokines, such as IL-4, IL-13 and IL-1ra were decreased compared to normal pregnant mice. In addition, serum levels of chemokine, such as SDF-1, G-CSF, M-CSF, IL-16, KC and MCP-1 were decreased in abortion model mice compared to normal pregnant mice. However, the expression levels of nesfatin-1/NUCB2 mRNA and protein in the uteri of implantation sites were significantly higher in abortion model mice than normal pregnant mice. These results suggest that uterine nesfatin-1/NUCB2 expression may be down-regulated by inflammatory cytokines and chemokines in the serum of pregnant mice. Moreover, this study suggests the possibility that nesfatin-1/NUCB2 expressed in the implantation sites may be associated with the maintenance of pregnancy.

Adropin acts in the rat paraventricular nucleus to influence neuronal excitability

Adropin is a peptide hormone with cardiovascular and metabolic roles in the periphery, including effects on glucose and lipid homeostasis. Central administration of adropin has been shown to inhibit water intake in rats; however, the site at which central adropin acts has yet to be elucidated. The hypothalamic paraventricular nucleus (PVN), a critical autonomic control center, plays essential roles in the control of fluid balance, energy homeostasis, and cardiovascular regulation, and is, therefore, a potential target for centrally acting adropin. In the present study, we used whole cell patch-clamp techniques to examine the effects of adropin on the excitability of neurons within the PVN. All three neuronal subpopulations (magnocellular, preautonomic, and neuroendocrine) in the PVN were found to be responsive to bath-application of 10 nM adropin, which elicited responses in 68% of cells tested (n = 57/84). The majority of cells (58%) depolarized (5.2 ± 0.3 mV; n = 49) in response to adropin, whereas the remaining responsive cells (10%) hyperpolarized (-3.4 ± 0.5 mV; n = 8), effects that were shown to be concentration-dependent. Additionally, responses were maintained in the presence of 1 μM TTX in 75% of cells tested (n = 9/12), and voltage-clamp analysis revealed that adropin had no effect on the amplitude or frequency of excitatory or inhibitory postsynaptic currents (EPSCs and IPSCs) in PVN neurons, suggesting the peptide exerts direct, postsynaptic actions on these neurons. Collectively, these findings suggest central adropin may exert its physiological effects through direct actions on neurons in the PVN.

Nesfatin-1: functions and physiology of a novel regulatory peptide

Nesfatin-1 was identified in 2006 as a potent anorexigenic peptide involved in the regulation of homeostatic feeding. It is processed from the precursor-peptide NEFA/nucleobindin 2 (NUCB2), which is expressed both in the central nervous system as well as in the periphery, from where it can access the brain via non-saturable transmembrane diffusion. In hypothalamus and brainstem, nesfatin-1 recruits the oxytocin, the melancortin and other systems to relay its anorexigenic properties. NUCB2/nesfatin-1 peptide expression in reward-related areas suggests that nesfatin-1 might also be involved in hedonic feeding. Besides its initially discovered anorexigenic properties, over the last years, other important functions of nesfatin-1 have been discovered, many of them related to energy homeostasis, e.g. energy expenditure and glucose homeostasis. Nesfatin-1 is not only affecting these physiological processes but also the alterations of the metabolic state (e.g. fat mass, glycemic state) have an impact on the synthesis and release of NUCB2 and/or nesfatin-1. Furthermore, nesfatin-1 exerts pleiotropic actions at the level of cardiovascular and digestive systems, as well as plays a role in stress response, behavior, sleep and reproduction. Despite the recent advances in nesfatin-1 research, a putative receptor has not been identified and furthermore potentially distinct functions of nesfatin-1 and its precursor NUCB2 have not been dissected yet. To tackle these open questions will be the major objectives of future research to broaden our knowledge on NUCB2/nesfatin-1.

Activation of Nesfatin-1-Containing Neurones in the Hypothalamus and Brainstem by Peripheral Administration of Anorectic Hormones and Suppression of Feeding via Central Nesfatin-1 in Rats

Peripheral anorectic hormones, such as glucagon-like peptide (GLP)-1, cholecystokinin (CCK)-8 and leptin, suppress food intake. The newly-identified anorectic neuropeptide, nesfatin-1, is synthesised in both peripheral tissues and the central nervous system, particularly by various nuclei in the hypothalamus and brainstem. In the present study, we examined the effects of i.p. administration of GLP-1 and CCK-8 and co-administrations of GLP-1 and leptin at subthreshold doses as confirmed by measurement of food intake, on nesfatin-1-immunoreactive (-IR) neurones in the hypothalamus and brainstem of rats by Fos immunohistochemistry. Intraperitoneal administration of GLP-1 (100 μg/kg) caused significant increases in the number of nesfatin-1-IR neurones expressing Fos-immunoreactivity in the supraoptic nucleus (SON), the area postrema (AP) and the nucleus tractus solitarii (NTS) but not in the paraventricular nucleus (PVN), the arcuate nucleus (ARC) or the lateral hypothalamic area (LHA). On the other hand, i.p. administration of CCK-8 (50 μg/kg) resulted in marked increases in the number of nesfatin-1-IR neurones expressing Fos-immunoreactivity in the SON, PVN, AP and NTS but not in the ARC or LHA. No differences in the percentage of nesfatin-1-IR neurones expressing Fos-immunoreactivity in the nuclei of the hypothalamus and brainstem were observed between rats treated with saline, GLP-1 (33 μg/kg) or leptin. However, co-administration of GLP-1 (33 μg/kg) and leptin resulted in significant increases in the number of nesfatin-1-IR neurones expressing Fos-immunoreactivity in the AP and the NTS. Furthermore, decreased food intake induced by GLP-1, CCK-8 and leptin was attenuated significantly by pretreatment with i.c.v. administration of antisense nesfatin-1. These results indicate that nesfatin-1-expressing neurones in the brainstem may play an important role in sensing peripheral levels of GLP-1 and leptin in addition to CCK-8, and also suppress food intake in rats.

Neutrophil/Lymphocyte Ratio, Serum Endocan, and Nesfatin-1 Levels in Patients with Psoriasis Vulgaris Undergoing Phototherapy Treatment

Background

Psoriasis is an autoimmune, inflammatory, and chronic disease. Recent studies have evaluated serum endocan and nesfatin-1 levels in patients with inflammatory disorders. The neutrophil-to-lymphocyte ratio (NLR) is an inflammatory marker currently used in many diseases. The aim of the present study was to evaluate NLR, serum endocan, and nesfatin-1 levels in psoriasis vulgaris before and after narrow-band ultraviolet B (NB-UVB) phototherapy treatment and compared to healthy controls.

Material/Methods

This study was conducted on a total of 88 cases, 39 of which had psoriasis vulgaris and 49 were healthy volunteers. Thirty-nine psoriasis vulgaris patients underwent NB-UVB phototherapy treatment for 3 months. NLR, serum endocan, and nesfatin-1 levels were measured in all psoriasis patients before and after NB-UVB phototherapy and in the control group.

Results

Compared with the control group, neutrophil count and NLR were significantly higher (p<0.001) in psoriasis patients before NB-UVB phototherapy. Serum endocan levels were significantly correlated with disease activity before treatment. There was no significant difference in NLR, serum endocan, and nesfatin-1 levels in psoriasis patients before and after NB-UVB phototherapy (p>0.05).

Conclusions

The current study shows that NLR was higher in psoriasis vulgaris patients when compared with the control group, whereas serum endocan and nesfatin-1 levels were not significantly different. In addition, NB-UVB phototherapy did not affect NLR, serum endocan, or nesfatin-1 levels. Further larger-scale studies are required on this subject.

Nesfatin-1: a new energy-regulating peptide with pleiotropic functions. Implications at cardiovascular level

Nesfatin-1 is a new energy-regulating peptide widely expressed at both central and peripheral tissues with pleiotropic effects. In the last years, the study of nesfatin-1 actions and its possible implication in the development of different diseases has created a great interest among the scientific community. In this review, we will summarize nesfatin-1 main functions, focusing on its cardiovascular implications.

Adropin acts in brain to inhibit water drinking: potential interaction with the orphan G protein-coupled receptor, GPR19

Adropin, a recently described peptide hormone produced in the brain and liver, has been reported to have physiologically relevant actions on glucose homeostasis and lipogenesis, and to exert significant effect on endothelial function. We describe a central nervous system action of adropin to inhibit water drinking and identify a potential adropin receptor, the orphan G protein-coupled receptor, GPR19. Reduction in GPR19 mRNA levels in medial basal hypothalamus of male rats resulted in the loss of the inhibitory effect of adropin on water deprivation-induced thirst. The identification of a novel brain action of adropin and a candidate receptor for the peptide should extend and accelerate the study of the potential therapeutic value of adropin or its mimetics for the treatment of metabolic disorders.

Nucleobindin 1 (NUCB1) is a Golgi-resident marker of neurons

Nucleobindin 1 (NUCB1; also known as CALNUC or NUC) is a putative DNA- and calcium-binding protein and exhibits significant structural homology with the protein nucleobindin 2 (NUCB2; also known as nesfatin). While NUCB2 has been mapped in detail in the brain and implicated in the hypothalamic control of energy metabolism, no study has to date addressed the presence of NUCB1 in the central nervous system. Here we have explored the expression and distribution of NUCB1 in the rat brain and spinal cord, using RT-PCR, immunofluorescence and in situ hybridization. NUCB1 mRNA and protein was found to be present in all brain regions, extending to the spinal cord and dorsal root ganglia. Double-staining for NUCB1 and NeuN, glial fibrillary acidic protein and myelin basic protein revealed that NUCB1 is exclusively found in neurons, and not in glial or ependymal cells. Notably, NUCB1-immunoreactivity was observed in all neurons examined, making no distinction between previously identified glutamatergic and GABAergic populations, including those that are known not to stain for NeuN. This included the markedly more restricted population of NUCB2-expressing neurons in the brain. The protein was detected in cell somata and proximal dendrites, but not in axons or terminal structures. Further examination of the subcellular distribution of NUCB1 using organelle-specific markers revealed its consistent presence in the Golgi apparatus. These findings identify NUCB1 as a novel pan-neuronal marker. Along with the recent demonstration of broad expression of the protein in endocrine cells, the present results suggest that NUCB1 may play a role in spatiotemporal calcium handling in signaling cells.

Th 17 Cells and Nesfatin-1 are associated with Spontaneous Abortion in the CBA/j × DBA/2 Mouse Model

The pregnancy and abortion process involves a complex mechanism with various immune cells present in the implantation sites and several hormones associated with pregnancy, such as leptin, ghrelin and nesfatin-1. However, the mechanism underlying spontaneous abortion by maternal T helper 17 (Th17) present in the implantation sites and nesfatin-1, which is of anorexigenic hormones, is not fully understood so far. Therefore, the purpose of this study was to examine the possible roles of Th17 cells present in the implantation sites and nesfatin-1 expressed in the uterus on spontaneous abortion using the CBA/j × DBA/2 mouse model. Th17 transcription factor, ROR-γt mRNA expression was significantly increased in the abortion sites compared with the implantation sites of abortion model mice on day 14.5 and 19.5 of pregnancy. In addition, the expression levels of IL(-1)7A mRNA were significantly higher in abortion sites than in implantation sites on day 14.5 and 19.5. Moreover, the nesfatin-1/NUCB2 protein and mRNA levels were increased in abortion sites compared with levels in implantation sites of both normal pregnant and abortion model mice on day 14.5 of pregnancy. Interestingly, nesfatin- 1/NUCB2 serum levels were not changed throughout the whole pregnancy in abortion model mice, but its serum level was dramatically increased on day 14.5, and then rapidly decreased on day 19.5 in normal pregnant mice. In this study, we showed for the first time the expression of nesfatin-1/NUCB2 mRNA and protein in implantation sites during pregnancy. The present results suggest that Th17 cells in the uterus may play an important role in the period of implantation and for maintenance of pregnancy. Furthermore, the present results suggest that Th17 cells in implantation sites may be a key regulator for maintenance of pregnancy and provides evidence that activation of these cells may be regulated by nesfatin-1/NUCB2. Further study is needed to elucidate the role of nesfatin-1 expressed in the uterus during pregnancy.

Depression-like Behavior Induced by Nesfatin-1 in Rats: Involvement of Increased Immune Activation and Imbalance of Synaptic Vesicle Proteins

Depression is a multicausal disorder and has been associated with metabolism regulation and immuno-inflammatory reaction. The anorectic molecule nesfatin-1 has recently been characterized as a potential mood regulator, but its precise effect on depression and the possible mechanisms remain unknown, especially when given peripherally. In the present study, nesfatin-1 was intraperitoneally injected to the rats and the depression-like behavior and activity of the hypothalamic-pituitary-adrenal (HPA) axis were evaluated. The plasma concentrations of nesfatin-1, interleukin 6 (IL-6), and C-reactive protein (CRP); and the hypothalamic expression levels of nesfatin-1, synapsin I, and synaptotagmin I mRNA were evaluated in nesfatin-1 chronically treated rats. The results showed that both acute and chronic administration of nesfatin-1 increased immobility in the forced swimming test (FST), and resulted in the hyperactivity of HPA axis, as indicated by the increase of plasma corticosterone concentration and hypothalamic expression of corticotropin-releasing hormone (CRH) mRNA. Moreover, after chronic nesfatin-1 administration, the rats exhibited decreased activity and exploratory behavior in the open field test (OFT) and increased mRNA expression of synapsin I and synaptotagmin I in the hypothalamus. Furthermore, chronic administration of nesfatin-1 elevated plasma concentrations of IL-6 and CRP, which were positively correlated with despair behavior, plasma corticosterone level, and the hypothalamic mRNA expression of synapsin I and synaptotagmin I. These results indicated that exogenous nesfatin-1 could induce the immune-inflammatory activation, which might be a central hug linking the depression-like behavior and the imbalanced mRNA expression of synaptic vesicle proteins in the hypothalamus.

Nesfatin-1 - More than a food intake regulatory peptide

Nesfatin-1 was discovered a decade ago and despite the fact that it represents just one of a multitude of food intake-inhibiting factors it received increasing attention. This led to a detailed characterization of NUCB2/nesfatin-1's physiological property to reduce food intake and also gave rise to an involvement in the long term regulation of body weight, especially under conditions of obesity. In addition, studies indicated the involvement of NUCB2/nesfatin-1 in other homeostatic functions as well: glucose homeostasis, water intake, gastrointestinal functions, temperature regulation, cardiovascular functions, puberty onset and sleep. These pleiotropic actions underline the physiological relevance of this peptide. Recently, the involvement of NUCB2/nesfatin-1 in psychiatric disorders such as anxiety has been investigated giving rise to the speculation that NUCB2/nesfatin-1 represents a peptidergic link between eating and anxiety/depression disorders.

Nesfatin-1 and Vitamin D levels may be associated with systolic and diastolic blood pressure values and hearth rate in polycystic ovary syndrome

Obesity, insulin resistance (IR), inflammation, and hyperandrogenism may lead to polycystic ovary syndrome (PCOS) and hypertension. Nesfatin-1 (N1) may be related to IR, obesity, and hypertension. Furthermore, a vitamin D (VD) deficiency is associated with hypertension and PCOS. We aimed to investigate N1 and VD levels in PCOS that have an effect on systolic and diastolic blood pressure (BP) and heart rate (HR).This study included 54 patients with PCOS and 48 age-body mass index (BMI)-matched healthy controls. PCOS was diagnosed according to clinical practice guidelines. Ferriman-Gallwey scores (FGS) were calculated, while N1, VD, and other hormonal and biochemical parameters were measured for all subjects. Systolic and diastolic BP was measured as well. HR was calculated using an electrocardiogram.The levels of N1 (p < 0.001), high-sensitivity C-reactive protein (hs-CRP) (p = 0.036), homeostasis model assessment as an index of insulin resistance (HOMA-IR) (p < 0.001), systolic (p < 0.001) and diastolic (p < 0.001) BP and HR (p < 0.001) in the PCOS group were significantly higher than in the control group. However, the VD levels of the PCOS group were lower than the control group (p = 0.004). N1 had a strong positive correlation with BMI, HOMA-IR, hs-CRP, luteinizing hormone, systolic and diastolic BP, and HR. VD levels were negatively correlated with HOMA-IR and luteinizing hormone.Elevated N1 and decreased VD levels may be related to the presence of high-normal BP or hypertension in PCOS subjects.  N1 level may be associated with an increased BP due to its relation to inflammation and IR.

Nesfatin-1 and Vitamin D levels may be associated with systolic and diastolic blood pressure values and hearth rate in polycystic ovary syndrome

Obesity, insulin resistance (IR), inflammation, and hyperandrogenism may lead to polycystic ovary syndrome (PCOS) and hypertension. Nesfatin-1 (N1) may be related to IR, obesity, and hypertension. Furthermore, a vitamin D (VD) deficiency is associated with hypertension and PCOS. We aimed to investigate N1 and VD levels in PCOS that have an effect on systolic and diastolic blood pressure (BP) and heart rate (HR).This study included 54 patients with PCOS and 48 age-body mass index (BMI)-matched healthy controls. PCOS was diagnosed according to clinical practice guidelines. Ferriman-Gallwey scores (FGS) were calculated, while N1, VD, and other hormonal and biochemical parameters were measured for all subjects. Systolic and diastolic BP was measured as well. HR was calculated using an electrocardiogram.The levels of N1 (p < 0.001), high-sensitivity C-reactive protein (hs-CRP) (p = 0.036), homeostasis model assessment as an index of insulin resistance (HOMA-IR) (p < 0.001), systolic (p < 0.001) and diastolic (p < 0.001) BP and HR (p < 0.001) in the PCOS group were significantly higher than in the control group. However, the VD levels of the PCOS group were lower than the control group (p = 0.004). N1 had a strong positive correlation with BMI, HOMA-IR, hs-CRP, luteinizing hormone, systolic and diastolic BP, and HR. VD levels were negatively correlated with HOMA-IR and luteinizing hormone.Elevated N1 and decreased VD levels may be related to the presence of high-normal BP or hypertension in PCOS subjects.  N1 level may be associated with an increased BP due to its relation to inflammation and IR.

The evaluation of Nesfatin-1 levels in patients with and without intrauterine growth restriction

OBJECTIVE

To evaluate Nesfatin-1 levels in patients with and without intrauterine growth restriction and to analyze the correlation between Nesfatin-1 levels and fetal birth weights.

METHODS

This study comprised a total of 81 cases; 41 patients with IUGR and 40 healthy cases. Demographic data, pregnancy weeks, fetal birth weights and Nesfatin-1 levels were all recorded. The Nesfatin-1 levels were compared between the groups and the correlation between fetal birth weights and Nesfatin-1 levels was analyzed.

RESULTS

No statistical significant difference was determined between the groups in terms of demographic data (p > 0.05). Average birth weights were determined as 3420 ± 259 g in the control group and 2041 ± 350 g in the IUGR group, which was found to be statistically unequal (p = 0.001). The average Nesfatin levels in the control group were 0.069 ± 0.011 and 0.094 ± 0.042 in the IUGR group. This difference was statistically unequal (p = 0.001). While no correlation was determined between Nesfatin levels and fetal birthweights in the control group (r = -0.034 versus p = 0.836), in the IUGR group and when all the cases were evaluated together, a statistically moderately significant negative correlation was determined (r = -0.469, p = 0.002 and r = -0.251, p = 0.024, respectively).

CONCLUSIONS

Although intrauterine growth is a multifactorial process, the effect mechanism has not yet been established. The results of this study offer some indications about the possible effect of Nesfatin 1 on fetal growth.

Nesfatin-1 as a new potent regulator in reproductive system

Nesfatin-1 is a recently discovered anorexigenic peptide which is distributed in several brain areas implicated in the feeding and metabolic regulation. Recently, it has been reported that nesfatin-1 is expressed not only in brain, but also in peripheral organs such as digestive organs, adipose tissues, heart, and reproductive organs. Nesfatin-1 is markedly expressed in the pancreas, stomach and duodenum. Eventually, the nesfatin-1 expression in the digestive organs may be regulated by nutritional status, which suggests a regulatory role of peripheral nesfatin-1 in energy homeostasis. Nesfatin-1 is also detected in the adipose tissues of humans and rodents, indicating that nesfatin-1 expression in the fat may regulate food intake independently, rather than relying on leptin. In addition, nesfatin-1 is expressed in the heart as a cardiac peptide. It suggests that nesfatin-1 may regulate cardiac function and encourage clinical potential in the presence of nutrition-dependent physio-pathologic cardiovascular diseases. Currently, only a few studies demonstrate that nesfatin-1 is expressed in the reproductive system. However, it is not clear yet what function of nesfatin-1 is in the reproductive organs. Here, we summarize the expression of nesfatin-1 and its roles in brain and peripheral organs and discuss the possible roles of nesfatin-1 expressed in reproductive organs, including testis, epididymis, ovary, and uterus. We come to the conclusion that nesfatin-1 as a local regulator in male and female reproductive organs may regulate the steroidogenesis in the testis and ovary and the physiological activity in epididymis and uterus.

A role of nesfatin-1/NucB2 in dehydration-induced anorexia

Nesfatin-1/NucB2, an anorexigenic molecule, is expressed mainly in the hypothalamus, particularly in the supraoptic nucleus (SON) and the paraventricular nucleus (PVN). Nesfatin-1/NucB2 is also expressed in the subfornical organ (SFO). Because the SON and PVN are involved in body fluid regulation, nesfatin-1/NucB2 may be involved in dehydration-induced anorexia. To clarify the effects of endogenous nesfatin-1/NucB2, we studied changes in nesfatin-1/NucB2 mRNA levels in the SFO, SON, and PVN in adult male Wistar rats after exposure to osmotic stimuli by using in situ hybridization histochemistry. Significant increases in nesfatin-1/NucB2 mRNA levels, ∼2- to 3-fold compared with control, were observed in the SFO, SON, and PVN following water deprivation for 48 h, consumption of 2% NaCl hypertonic saline in drinking water for 5 days, and polyethylene glycol-induced hypovolemia. In addition, nesfatin-1/NucB2 expression was increased in response to water deprivation in a time-dependent manner. These changes in nesfatin-1/NucB2 mRNA expression were positively correlated with plasma sodium concentration, plasma osmolality, and total protein levels in all of the examined nuclei. Immunohistochemistry for nesfatin-1/NucB2 revealed that nesfatin-1/NucB2 protein levels were also increased after 48 h of dehydration and attenuated by 24 h of rehydration. Moreover, intracerebroventricular administration of nesfatin-1/NucB2-neutralizing antibody after 48 h of water deprivation resulted in a significant increase in food intake compared with administration of vehicle alone. These results suggested that nesfatin-1/NucB2 is a crucial peptide in dehydration-induced anorexia.

Cellular actions of nesfatin-1 in the subfornical organ

Nesfatin-1, a centrally acting anorexigenic peptide, is produced in several brain areas involved in metabolic processes and has been implicated in the control of ingestive behaviours and cardiovascular functions. The present study aimed to determine whether the subfornical organ (SFO), a central nervous system (CNS) site that has been extensively implicated in the regulation of appetite and thirst, may represent a potential site for central actions of nesfatin-1. We first used the reverse transcriptase-polymerase chain reaction and were able to confirm the presence of mRNA for the nucleobindin-2 gene in the SFO. We then used whole-cell patch clamp recordings to investigate the influence of nesfatin-1 on the membrane potential of dissociated SFO neurones. A total of 80.3% (49 of 61) of neurones tested showed a response to nesfatin-1 (100 nm, 10 nm and 1 nm). Of these, 47.5% depolarised, with a mean depolarisation of 8.2 ± 0.9 mV (n = 29) and 32.8% hyperpolarised with a mean hyperpolarisation of -8.9 ± 1.2 mV (n = 20). Peak magnitudes were seen at a concentration of 1 nm nesfatin-1, whereas no effect was observed at 100 pm nesftain-1 (n = 3). Furthermore, voltage clamp ramp and step protocols revealed a nesfatin-1 induced activation of the delayed rectifier potassium conductance, IK . Pharmacological blockade of this conductance greatly reduced the magnitude and occurrence of the observed hyperpolarisations. The present study thus demonstrates that nesfatin-1 has the ability to influence the membrane potential of SFO neurones, and thus identifies the SFO as a potential site at which nesfatin-1 may act to regulate ingestive behaviour and cardiovascular control.

Biomarkers in the field of obesity and its related comorbidities

INTRODUCTION

The prevalence of obesity has increased dramatically in the last decades both in children and adults and is now considered a major health problem. It is associated with numerous comorbidities such as hypertension, dyslipidemia, diabetes and subsequent cardiovascular disease (CVD). One of the mechanisms that connect obesity with these comorbidities is the secretion of so-called adipocytokines or adipokines by the adipose tissue itself. Most adipokines with pro-inflammatory properties are overproduced with increasing adiposity, whereas some adipokines with anti-inflammatory or insulin-sensitizing properties, like adiponectin, are decreased. This dysregulation of adipokines production may promote obesity-linked metabolic disorders and CVD. Except adipokines a wide complex network of chemicals balances pro-inflammatory and anti-inflammatory effects.

AREAS COVERED

In this review, we summarize the role of various adipokines and other chemicals associated with obesity and its related cardiometabolic comorbidities, with a special focus on recent evidence showing their potential role as biomarkers whose expression are indicative of obesity and its complications.

EXPERT OPINION

Biomarkers associated with obesity, type 2 diabetes (T2D) and CVD could prove beneficial for early identification, proper treatment and good life assurance. Unfortunately, the complexity of biological pathways interactions is such that further research is necessary before any of these markers could reach an accurate diagnostic value.

Role of NUCB2/Nesfatin-1 in the hypothalamic control of energy homeostasis

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 nesfatin-1, was first described in 2006 and nesfatin-1 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 nesfatin-1 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 nesfatin-1's effects on food intake and body weight and highlights important missing links regarding cellular signaling mechanisms involved in nesfatin-1's action.

The role of nesfatin-1 in the regulation of food intake and body weight: recent developments and future endeavors

Nesfatin-1 was discovered in 2006 and introduced as a potential novel anorexigenic modulator of food intake and body weight. The past years have witnessed increasing evidence establishing nesfatin-1 as a potent physiological inhibitor of food intake and body weight and unravelled nesfatin-1's interaction with other brain transmitters to exert its food consumption inhibitory effect. As observed for other anorexigenic brain neuropeptides, nesfatin-1 is also likely to exert additional, if not pleiotropic, actions in the brain and periphery. Recent studies established the prominent expression of the nesfatin-1 precursor, nucleobindin2 (NUCB2), in the stomach and pancreas, where nesfatin-1 influences endocrine secretion. This review will highlight the current experimental state-of-knowledge on the effects of NUCB2/nesfatin-1 on food intake, body weight and glucose homeostasis. Potential implications in human obesity will be discussed in relation to the evidence of changes in circulating levels of NUCB2/nesfatin-1 in disease states, the occurrence of genetic NUCB2 polymorphisms and--in contrast to several other hormones--the independence of leptin signalling known to be blunted under conditions of chronically increased body weight.

Multi-functional peptide hormone NUCB2/nesfatin-1

The recently discovered nesfatin-1 is regulated by hunger and satiety. The precursor protein NUCB2 is proteolytically cleaved into three resulting fragments: nesfatin-1, nesfatin-2, and nesfatin-3. The middle segment of nesfatin-1 (M30) is responsible for limiting food intake, while the exact physiological role of nesfatin-2 and nesfatin-3 are not currently known yet. This hormone plays role/roles on diabetic hyperphagia, epilepsy, mood, stress, sleeping, anxiety, hyperpolarization, depolarization, and reproductive functions. This review will address nesfatin, focusing on its discovery and designation, biochemical structure, scientific evidence of its anorexigenic character, the results of the human and animal studies until the present day, its main biochemical and physiological effects, and its possible clinical applications.

Peripheral effects of nesfatin-1 on glucose homeostasis

Aims/hypothesis

The actions of peripherally administered nesfatin-1 on glucose homeostasis remain controversial. The aim of this study was to characterize the mechanisms by which peripheral nesfatin-1 regulates glucose metabolism.

Methods

The effects of nesfatin-1 on glucose metabolism were examined in mice by continuous infusion of the peptide via osmotic pumps. Changes in AKT phosphorylation and Glut4 were investigated by Western blotting and immnuofluorescent staining. Primary myocytes, adipocytes and hepatocytes were isolated from male mice.

Results

Continuous peripheral infusion of nesfatin-1 altered glucose tolerance and insulin sensitivity in mice fed either normal or high fat diet, while central administration of nesfatin-1 demonstrated no effect. Nesfatin-1 increases insulin secretion in vivo, and in vitro in cultured min6 cells. In addition, nesfatin-1 up-regulates the phosphorylation of AKT in pancreas and min6 islet cells. In mice fed normal diet, peripheral nesfatin-1 significantly increased insulin-stimulated phosphorylation of AKT in skeletal muscle, adipose tissue and liver; similar effects were observed in skeletal muscle and adipose tissue in mice fed high fat diet. At basal conditions and after insulin stimulation, peripheral nesfatin-1 markedly increased GLUT4 membrane translocation in skeletal muscle and adipose tissue in mice fed either diet. In vitro studies showed that nesfatin-1 increased both basal and insulin-stimulated levels of AKT phosphorylation in cells derived from skeletal muscle, adipose tissue and liver.

Conclusions

Our studies demonstrate that nesfatin-1 alters glucose metabolism by mechanisms which increase insulin secretion and insulin sensitivity via altering AKT phosphorylation and GLUT 4 membrane translocation in the skeletal muscle, adipose tissue and liver.