A novel adipocytokine, nesfatin-1 modulates peripheral arterial contractility and blood pressure in rats

Nesfatin-1 is a regulator of inflammation with implications during obesity and metabolic syndrome

Nesfatin-1, derived from the nucleobindin 2 (NUCB2) precursor, is a potent anorexigenic peptide that was discovered in 2006. Since its identification in the hypothalamus, it has been shown to have wide ranging actions within and outside of the central nervous system. One of these actions is the regulation of inflammation, which could potentially be exploited therapeutically in the context of obesity-associated inflammation in adipose tissue. Here, we review recent advances in our knowledge about the ability of nesfatin-1 to control inflammation by regulating NFκB signaling, which likely attenuates pro-inflammatory cytokine production and inhibits apoptosis.

Nesfatin-1: A Novel Diagnostic and Prognostic Biomarker in Digestive Diseases

Nesfatin-1, deriving from a precursor protein, NUCB2, is a newly discovered molecule with anti-apoptotic, anti-inflammatory, antioxidant, and anorexigenic effects. It was initially identified in the central nervous system (CNS) and received increasing interest due to its energy-regulating properties. However, research showed that nesfatin-1 is also expressed in peripheral tissues, including the digestive system. The aim of this review is to give a résumé of the present state of knowledge regarding its structure, immunolocalization, and potential implications in diseases with inflammatory components. The main objective was to focus on its clinical importance as a diagnostic biomarker and potential therapeutic molecule in a variety of disorders, among which digestive disorders were of particular interest. Previous studies have shown that nesfatin-1 regulates the balance between pro- and antioxidant agents, which makes nesfatin-1 a promising therapeutic agent. Further in-depth research regarding the underlying mechanisms of action is needed for a better understanding of its effects.

How vascular smooth muscle cell phenotype switching contributes to vascular disease

Vascular smooth muscle cells (VSMCs) are the most abundant cell in vessels. Earlier experiments have found that VSMCs possess high plasticity. Vascular injury stimulates VSMCs to switch into a dedifferentiated type, also known as synthetic VSMCs, with a high migration and proliferation capacity for repairing vascular injury. In recent years, largely owing to rapid technological advances in single-cell sequencing and cell-lineage tracing techniques, multiple VSMCs phenotypes have been uncovered in vascular aging, atherosclerosis (AS), aortic aneurysm (AA), etc. These VSMCs all down-regulate contractile proteins such as α-SMA and calponin1, and obtain specific markers and similar cellular functions of osteoblast, fibroblast, macrophage, and mesenchymal cells. This highly plastic phenotype transformation is regulated by a complex network consisting of circulating plasma substances, transcription factors, growth factors, inflammatory factors, non-coding RNAs, integrin family, and Notch pathway. This review focuses on phenotypic characteristics, molecular profile and the functional role of VSMCs phenotype landscape; the molecular mechanism regulating VSMCs phenotype switching; and the contribution of VSMCs phenotype switching to vascular aging, AS, and AA. Video Abstract.

"Sibling" battle or harmony: crosstalk between nesfatin-1 and ghrelin

Ghrelin was first identified as an endogenous ligand of the growth hormone secretagogue receptor (GHSR) in 1999, with the function of stimulating the release of growth hormone (GH), while nesfatin-1 was identified in 2006. Both peptides are secreted by the same kind of endocrine cells, X/A-like cells in the stomach. Compared with ghrelin, nesfatin-1 exerts opposite effects on energy metabolism, glucose metabolism, gastrointestinal functions and regulation of blood pressure, but exerts similar effects on anti-inflammation and neuroprotection. Up to now, nesfatin-1 remains as an orphan ligand because its receptor has not been identified. Several studies have shown the effects of nesfatin-1 are dependent on the receptor of ghrelin. We herein compare the effects of nesfatin-1 and ghrelin in several aspects and explore the possibility of their interactions.

Interactions between nesfatin-1 and the autonomic nervous system-An overview

Nesfatin-1, an 82-amino acid polypeptide derived from the precursor protein nucleobindin-2 (NUCB2), was first discovered in 2006 in the rat hypothalamus. The effects and distribution of nesfatin-1 immunopositive neurons in the brain and spinal cord point towards a role of NUCB2/nesfatin-1 in autonomic regulation. Therefore, studies which have been conducted to investigate the interplay between nesfatin-1 and the autonomic nervous system were examined, and the outcomes of this research were summarized. NUCB2/nesfatin-1 immunoreactivity is widely distributed in autonomic centers of the brain and spinal cord in both rodents and humans. In several regions of the hypothalamus, midbrain and brainstem, nesfatin-1 modulates autonomic functions. On the other hand, the autonomic nervous system also influences the activity of nesfatin-1 neurons. Here, the vagus nerve seems to be a crucial factor in the regulation of nesfatin-1. In summary, although data here is still sparse, there is a clear interplay between nesfatin-1 and the autonomic nervous system, the precise clarification of which still requires further research to gain more insight into these complex relationships.

Nesfatin-1-like peptide is a negative regulator of cardiovascular functions in zebrafish and goldfish

Nucleobindins (NUCB1 and NUCB2) were originally identified as calcium and DNA binding proteins. Nesfatin-1 (NEFA/nucleobindin-2-Encoded Satiety and Fat-Influencing proteiN-1) is an 82 amino acid anorexigenic peptide encoded in the N-terminal region of NUCB2. We have shown that nesfatin-1 is a cardiosuppressor in zebrafish. Both NUCB1 and NUCB2 possess a -very highly conserved bioactive core. It was found that a nesfatin-1-like peptide (NLP) encoded in NUCB1 suppresses food intake in fish. In this research, we investigated whether NLP has nesfatin-1-like effects on cardiovascular functions. NUCB1/NLP-like immunoreactivity was found in the atrium and ventricle of the heart and skeletal muscle of zebrafish. Intraperitoneal injection (IP) of either zebrafish NLP or rat NLP suppressed cardiac functions in both zebrafish and goldfish. Irisin and RyR1b mRNA expression was downregulated by NLP in zebrafish cardiac and skeletal muscles. However, cardiac ATP2a2 mRNA expression was elevated after NLP injection. Administration of scrambled NLP did not affect irisin, RyR1b or ATP2a2 mRNA expression in zebrafish. Together, these results implicate NLP as a suppressor of cardiovascular physiology in zebrafish and goldfish.

Plasma nesfatin-1 and DDP-4 levels in patients with coronary artery disease: Kozani study

Background

Nesfatin-1, a novel adipokine and dipeptidyl peptidase-4 (DPP4), a mam malian serine protease, are potent factors of atherosclerosis. In the present cross-sectional study, we investigated whether the plasma nesfatin-1 and DPP4 is associated with the prevalence and severity of coronary artery disease (CAD) with and without diabetes mellitus (DM).

Methods

We consecutively enrolled a total of 240 patients with significant CAD (previous revascularization or angiographically-proven coronary artery stenosis > 50%) presented with either unstable angina (UA, N = 76) or stable chronic CAD (SCAD, N = 165). 85 patients with at least 2 classical cardiovascular risk factors but without significant CAD served as controls. The severity of CAD was assessed using coronary angiography by the Gensini score. Clinical parameters, glycemic and lipid profile, high-sensitivity CRP (hsCRP), nesfatin-1 and DPP4 levels were assayed.

Results

No differences were found for age, sex, hypertension and diabetes distribution between groups. Low nesfatin-1 levels were found in both CAD groups (UA & SCAD) with respect to controls. The difference between UA and SCAD groups was marginally non-significant. There was a significant increase of DPP4 along UA to SCAD and control groups. Differences between groups remained unchanged in non-diabetic participants. Nesfatin-1 significantly correlated to hsCRP (r = − 0.287, p = 0.036), HOMA-IR (r = − 0.587, p = 0.007) and hyperlipidemia (r = − 0.331, p = 0.034). DPP4 was significantly associated with hs-CRP (r = 0.353 p < 0.001) and FPG (r = 0.202, p = 0.020) in univariate analysis, but those correlations were lost in multiple regression analysis. There was a negative correlation between nesfatin-1 and the severity of CAD, quantified by the Gensini score (r = − 0.511, p < 0.001), but no association was found for DPP4.

Conclusions

Serum DPP4 levels are increased in patients with CAD, while serum nesfatin-1 levels have a negative association with both the incidence and the severity of CAD. These results are independent of the presence of diabetes mellitus. In addition, both peptides have a strong association with hsCRP.

Trial registration ClinicalTrials.gov Identifier: NCT00306176

Nesfatin-1 Receptor: Distribution, Signaling and Increasing Evidence for a G Protein-Coupled Receptor - A Systematic Review

BACKGROUND

Nesfatin-1 is an 82-amino acid polypeptide, cleaved from the 396-amino acid precursor protein nucleobindin-2 (NUCB2) and discovered in 2006 in the rat hypothalamus. In contrast to the growing body of evidence for the pleiotropic effects of the peptide, the receptor mediating these effects and the exact signaling cascades remain still unknown.

METHODS

This systematic review was conducted using a search in the Embase, PubMed, and Web of Science databases. The keywords "nesfatin-1" combined with "receptor", "signaling", "distribution", "pathway", g- protein coupled receptor", and "binding" were used to identify all relevant articles reporting about potential nesfatin-1 signaling and the assumed mediation via a G_i protein-coupled receptor.

RESULTS

Finally, 1,147 articles were found, of which 1,077 were excluded in several steps of screening, 70 articles were included in this systematic review. Inclusion criteria were studies investigating nesfatin-1's putative receptor or signaling cascade, observational preclinical and clinical studies, experimental studies, registry-based studies, cohort studies, population-based studies, and studies in English language. After screening for eligibility, the studies were assigned to the following subtopics and discussed regarding intracellular signaling of nesfatin-1 including the potential receptor mediating these effects and downstream signaling of the peptide.

CONCLUSION

The present review sheds light on the various effects of nesfatin-1 by influencing several intracellular signaling pathways and downstream cascades, including the peptide's influence on various hormones and their receptors. These data point towards mediation via a G_i protein-coupled receptor. Nonetheless, the identification of the nesfatin-1 receptor will enable us to better investigate the exact mediating mechanisms underlying the different effects of the peptide along with the development of agonists and antagonists.

Detection of NUCB2/nesfatin-1 in cerebrospinal fluid of multiple sclerosis patients

NUCB2/nesfatin-1 was originally discovered as an anorexigenic peptide. However, recent studies revealed various additional functions including the regulation of inflammation. However, there are no studies that investigated the involvement of NUCB2/nesfatin-1 in neuroinflammatory diseases. Here, we aimed to investigate the involvement of NUCB2/nesfatin-1 in a representative neuroinflammatory disease, multiple sclerosis (MS).

Cerebrospinal fluids (CSF) were collected from 24 MS patients and 10 control subjects and NUCB2/nesfatin-1, proinflammatory cytokines (TNF-α, IL-1β) and anti-inflammatory cytokines (IL-10, TGF-β) levels were measured by using ELISA assay. Also the expression of NUCB2/nesfatin-1 in the CSF of MS patient was investigated by western blot analysis.

Expression of NUCB2/nesfatin-1 was confirmed in the CSF of the MS patient by western blot analysis. NUCB2/nesfatin-1 levels were significantly higher in the CSF of the MS patients. Among the measured cytokines, only IL-1β was lower in the CSF of the MS patients.

We report for the first time increased NUCB2/nesfatin-1 levels in the CSF of MS patients.

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.

Nesfatin-1 suppresses interleukin-1β-induced inflammation, apoptosis, and cartilage matrix destruction in chondrocytes and ameliorates osteoarthritis in rats

Osteoarthritis (OA) is a chronic degenerative joint disease, related to the overexpression of matrix metalloproteinases (MMPs), a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS), inflammation, and chondrocyte apoptosis. Nesfatin-1 is an adipokine, which plays an important role in the development of OA, especially in obese people. In the present study, cartilage degradation and apoptosis observed in OA patients was evaluated. Furthermore, the anti-inflammatory and anti-apoptotic effects of nesfatin-1, and its underlying in vitro and in vivo mechanisms were investigated. The results showed that nesfatin-1 increased significantly the expression of collagen type II alpha 1 chain (Col2a1), and reduced the expression of MMPs, ADAMTS5, cyclooxygenase (COX)-2, caspase-3, nitric oxide (NO), inducible nitric oxide synthase (iNOS), prostaglandin E2 (PGE2), interleukin (IL)-6, and chondrocyte apoptosis rate, which may be induced by IL-1β in rat chondrocytes. Furthermore, nesfatin-1 treatment prevented cartilage degeneration in the rat OA model. It was found that nesfatin-1 suppressed the IL-1β-induced activation of NF-κB, the mitogen-activated protein kinase (MAPK), and the Bax/Bcl-2 signal pathway in chondrocytes. These results suggest that in vivo nesfatin-1 could play a protective role in the development of OA and can be potentially used for its treatment.

Regulatory Peptide Nesfatin-1 and its Relationship with Metabolic Syndrome

Metabolic syndrome is associated with a group of conditions abdominal obesity, high triglyceride levels, reduction in low-density lipoprotein, increased blood pressure, and increased fasting blood glucose. Hence, it poses a risk for type 2 diabetes and cardiovascular diseases. The prevalence of metabolic syndrome increases with age. Nesfatin-1, which affects different systems, has recently been discovered as a regulatory peptide molecule. With the discovery of nesfatin-1, it has been reported to inhibit the intake of nutrients and have significant regulatory effects on energy metabolism. As nesfatin-1 is present in both central and peripheral tissues, it is thought to have many functions. In addition to its suppressive effect on food intake, nesfatin-1 has also been reported to have an effect on the blood glucose level for regulating cardiac functions and affecting obesity by providing weight loss. Considering the effects of nesfatin-1, it may be associated with metabolic syndrome.

Adipocytes-released Peptides Involved in the Control of Gastrointestinal Motility

The present review focuses on adipocytes-released peptides known to be involved in the control of gastrointestinal motility, acting both centrally and peripherally. Thus, four peptides have been taken into account: leptin, adiponectin, nesfatin-1, and apelin. The discussion of the related physiological or pathophysiological roles, based on the most recent findings, is intended to underlie the close interactions among adipose tissue, central nervous system, and gastrointestinal tract. The better understanding of this complex network, as gastrointestinal motor responses represent peripheral signals involved in the regulation of food intake through the gut-brain axis, may also furnish a cue for the development of either novel therapeutic approaches in the treatment of obesity and eating disorders or potential diagnostic tools.

Nesfatin-1 suppresses peripheral arterial remodeling without elevating blood pressure in mice

Nesfatin-1 is a novel anorexic peptide hormone that also exerts cardiovascular protective effects in rodent models. However, nesfatin-1 treatment at high doses also exerts vasopressor effects, which potentially limits its therapeutic application. Here, we evaluated the vasoprotective and vasopressor effects of nesfatin-1 at different doses in mouse models. Wild-type mice and those with the transgene nucleobindin-2, a precursor of nesfatin-1, were employed. Wild-type mice were randomly assigned to treatment with vehicle or nesfatin-1 at 0.2, 2.0 or 10 μg/kg/day (Nes-0.2, Nes-2, Nes-10, respectively). Subsequently, mice underwent femoral artery wire injury to induce arterial remodeling. After 4 weeks, injured arteries were collected for morphometric analysis. Compared with vehicle, nesfatin-1 treatments at 2.0 and 10 μg/kg/day decreased body weights and elevated plasma nesfatin-1 levels with no changes in systolic blood pressure. Furthermore, these treatments reduced neointimal hyperplasia without inducing undesirable remodeling in injured arteries. However, nesfatin-1 treatment at 0.2 μg/kg/day was insufficient to elevate plasma nesfatin-1 levels and showed no vascular effects. In nucleobindin-2-transgenic mice, blood pressure was slightly higher but neointimal area was lower than those observed in littermate controls. In cultured human vascular endothelial cells, nesfatin-1 concentration-dependently increased nitric oxide production. Additionally, nesfatin-1 increased AMP-activated protein kinase phosphorylation, which was abolished by inhibiting liver kinase B1. We thus demonstrated that nesfatin-1 treatment at appropriate doses suppressed arterial remodeling without affecting blood pressure. Our findings indicate that nesfatin-1 can be a therapeutic target for improved treatment of peripheral artery disease.

Associations between plasma nesfatin-1 levels and the presence and severity of coronary artery disease

Nesfatin-1 is a recently identified anorexigenic peptide mainly secreted from the brain and adipose tissue. Although nesfatin-1 may have pro-inflammatory and apoptotic properties, the association between plasma nesfatin-1 levels and coronary artery disease (CAD) has not been clarified yet. We investigated plasma nesfatin-1 levels in 302 patients undergoing elective coronary angiography. Of the 302 study patients, CAD was present in 172 (57%), of whom 67 had 1-vessel, 49 had 2-vessel, and 56 had 3-vessel disease. Compared with 130 patients without CAD, 172 with CAD had higher plasma nesfatin-1 levels (median 0.21 vs. 0.17 ng/mL, P < 0.01). A stepwise increase in nesfatin-1 levels was found depending on the number of > 50% stenotic coronary vessels: 0.17 in CAD(-), 0.20 in 1-vessel, 0.21 in 2-vessel, and 0.22 ng/mL in 3-vessel disease (P < 0.05). A high nesfatin-1 level (> 0.19 ng/mL) was found in 43% of patients with CAD(-), 55% of those with 1-vessel, 55% of those with 2-vessel, and 68% of those with 3-vessel disease (P < 0.05). Nesfatin-1 levels significantly correlated with the number of > 50% stenotic coronary segments (r = 0.14, P < 0.02). In multivariate analysis, plasma nesfatin-1 levels were a significant factor for CAD independent of atherosclerotic risk factors. The odds ratio for CAD was 1.71 (95% CI 1.01-2.91) for high nesfatin-1 level of > 0.19 ng/mL (P < 0.05). Thus, plasma nesfatin-1 levels were found to be high in patients with CAD and were associated with CAD independent of atherosclerotic risk factors, suggesting that high nesfatin-1 levels in patients with CAD may play a role in the development of coronary atherosclerosis.

Nesfatin-130-59 Injected Intracerebroventricularly Increases Anxiety, Depression-Like Behavior, and Anhedonia in Normal Weight Rats

Nesfatin-1 is a well-established anorexigenic peptide. Recent studies indicated an association between nesfatin-1 and anxiety/depression-like behavior. However, it is unclear whether this effect is retained in obesity. The aim was to investigate the effect of nesfatin-1_30-59—the active core of nesfatin-1—on anxiety and depression-like behavior in normal weight (NW) and diet-induced (DIO) obese rats. Male rats were intracerebroventricularly (ICV) cannulated and received nesfatin-1_30-59 (0.1, 0.3, or 0.9 nmol/rat) or vehicle 30 min before testing. Nesfatin-1_30-59 at a dose of 0.3 nmol reduced sucrose consumption in the sucrose preference test in NW rats compared to vehicle (–33%, p < 0.05), indicating depression-like/anhedonic behavior. This dose was used for all following experiments. Nesfatin-1_30-59 also reduced cookie intake during the novelty-induced hypophagia test (−62%, p < 0.05). Moreover, nesfatin-1_30-59 reduced the number of entries into the center zone in the open field test (−45%, p < 0.01) and the visits of open arms in the elevated zero maze test (−39%, p < 0.01) in NW rats indicating anxiety. Interestingly, DIO rats showed no behavioral alterations after the injection of nesfatin-1_30-59 (p > 0.05). These results indicate an implication of nesfatin-1_30-59 in the mediation of anxiety and depression-like behavior/anhedonia under normal weight conditions, while in DIO rats, a desensitization might occur.

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.

Nesfatin-1 ameliorates testicular injury and supports gonadal function in rats induced with testis torsion

Testicular torsion causes ischemia-reperfusion injury and an increased risk of infertility. Nesfatin-1 is a novel peptide with antioxidant, anti-inflammatory and anti-apoptotic properties. In the present study, we aimed to investigate the putative beneficial effects of nesfatin-1 on oxidative injury and impaired testicular function induced by testis torsion. Under anesthesia, male Sprague-Dawley rats (180-230 g; n = 24) had sham-operation or they underwent testicular torsion by rotating the left testis 720° and fixing it for 2 h, followed by a 2-h detorsion. Rats in each group were treated intraperitoneally with either nesfatin-1 (0.3 μg/kg) or saline prior to the torsion or sham-torsion. At the end of the 4-h experimental period, tissue samples were removed for evaluation of spermatozoa, molecular and histochemical analyses. In saline-treated torsion/detorsion group, a high percentage of abnormal spermatozoa with head defects was observed, which was abolished in nesfatin-1-treated torsion/detorsion group. The levels of 8-OHdG, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, caspase-3 were increased in the saline-treated torsion/detorsion group as compared to sham-operated group, while nesfatin-1 pre-treatment significantly decreased the expressions of the pro-inflammatory cytokines, depressed apoptosis, and also reduced the tubular degeneration. In addition, nesfatin-1 in torsion/detorsion group elevated expressions of transforming growth factor (TGF)-beta and reduced expressions of protein kinase B (AKT) and cAMP response element binding protein (CREB) in the testis tissue. The present findings show that nesfatin-1, by regulating AKT and CREB signaling pathways and pro-inflammatory/anti-inflammatory cytokine balance, preserves the spermatogenic cells and ameliorates torsion-detorsion-induced tubular degeneration.

Modulation of nesfatin-1-induced cardiovascular effects by the central cholinergic system

Nesfatin-1, a peptide whose receptor is yet to be identified, has been shown to be involved in the modulation of feeding, stress, and metabolic responses. Recently, increasing evidence has supported a modulatory role of nesfatin-1 in cardiovascular activity. We have previously reported that nesfatin-1 causes an increase in blood pressure in normotensive and hypotensive rats by increasing plasma catecholamine, vasopressin, and renin levels. Recent reports suggest that nesfatin-1 may activate the central cholinergic system. However, there is no evidence showing an interaction between central nesfatin-1 and the cholinergic system. Therefore, this study aimed to determine whether the central cholinergic system may have a functional role in the nesfatin-1-induced cardiovascular effect observed in normotensive rats. Intracerebroventricular injection of nesfatin-1 caused short-term increases in mean arterial pressure and heart rate responses including bradycardic/tachycardic phases in normotensive animals. Central injection of nesfatin-1 increased the acetylcholine and choline levels in the posterior hypothalamus, as shown in microdialysis studies. Central pretreatment with the cholinergic muscarinic receptor antagonist atropine and/or nicotinic receptor antagonist mecamylamine blocked nesfatin-1-induced cardiovascular effects. In conclusion, the results show that centrally administered nesfatin-1 produces a pressor effect on blood pressure and heart rate responses including bradycardic/tachycardic phases in normotensive rats. Moreover, according to our findings, the central cholinergic system can modulate nesfatin-1-evoked cardiovascular activity.

Nesfatin-1 functions as a switch for phenotype transformation and proliferation of VSMCs in hypertensive vascular remodeling

The phenotypic transformation from differentiated to dedifferentiated vascular smooth muscle cells (VSMCs) plays a crucial role in VSMC proliferation and vascular remodeling in many cardiovascular diseases including hypertension. Nesfatin-1, a multifunctional adipocytokine, is critically involved in the regulation of blood pressure. However, it is still largely unexplored whether nesfatin-1 is a potential candidate in VSMC phenotypic switch and proliferation in hypertension. Experiments were carried out in Wistar-Kyoto rats (WKY), spontaneously hypertensive rats (SHR), human VSMCs and primary rat aortic VSMCs. We showed that the expression of nesfatin-1 was upregulated in media layer of the aorta in SHR and SHR-derived VSMCs. Nesfatin-1 promoted VSMC phenotypic transformation, accelerated cell cycle progression and proliferation. Knockdown of nesfatin-1 inhibited the VSMC phenotype switch from a contractile to a synthetic state, attenuated cell cycle progression and retarded VSMC proliferation in SHR-derived VSMCs. Moreover, nesfatin-1-activated PI3K/Akt/mTOR signaling was abolished by JAK/STAT inhibitor WP1066, and the increased phosphorylation levels of JAK2/STAT3 in response to nesfatin-1 were suppressed by inhibition of PI3K/Akt/mTOR in VSMCs. Pharmacological blockade of the forming feedback loop between PI3K/Akt/mTOR and JAK2/STAT3 prevented the proliferation of nesfatin-1-incubated VSMCs and primary VSMCs from SHR. Chronic intraperitoneal injection of nesfatin-1 caused severe hypertension and cardiovascular remodeling in normal rats. In contrast, silencing of nesfatin-1 gene ameliorated hypertension, phenotype switching, and vascular remodeling in the aorta of SHR. Therefore, our data identified nesfatin-1 as a key modulator in hypertension and vascular remodeling by facilitating VSMC phenotypic switching and proliferation.

Nesfatin-1 promotes VSMC migration and neointimal hyperplasia by upregulating matrix metalloproteinases and downregulating PPARγ

The dedifferentiation, proliferation and migration of vascular smooth muscle cells (VSMCs) are essential in the progression of hypertension, atherosclerosis and intimal hyperplasia. Nesfatin-1 is a potential modulator in cardiovascular functions. However, the role of nesfatin-1 in VSMC biology has not been explored. The present study was designed to determine the regulatory role of nesfatin-1 in VSMC proliferation, migration and intimal hyperplasia after vascular injury. Herein, we demonstrated that nesfatin-1 promoted VSMC phenotype switch from a contractile to a synthetic state, stimulated VSMC proliferation and migration in vitro. At the molecular level, nesfatin-1 upregulated the protein and mRNA levels, as well as the promoter activities of matrix metalloproteinase 2 (MMP-2) and MMP-9, but downregulated peroxisome proliferator-activated receptor γ (PPARγ) levels and promoter activity in VSMCs. Blockade of MMP-2/9 or activation of PPARγ prevented the nesfatin-1-induced VSMC proliferation and migration. In vivo, knockdown of nesfatin-1 ameliorated neointima formation following rat carotid injury. Taken together, our results indicated that nesfatin-1 stimulated VSMC proliferation, migration and neointimal hyperplasia by elevating MMP2/MMP-9 levels and inhibiting PPARγ gene expression.

Insulinotropic nucleobindin-2/nesfatin-1 is dynamically expressed in the haemochorial mouse and human placenta

The placenta is the physiological bridge between mother and fetus and has life-sustaining functions during pregnancy, including metabolic regulation, fetal protection and hormone secretion. Nucleobindin-2 (NUCB2) is a calcium- and DNA-binding protein and precursor of nesfatin-1, a signalling peptide with multiple functions, including regulation of energy homeostasis and glucose transport. These are also key functions of the placenta, yet NUCB2/nesfatin-1 expression has never been comprehensively studied in this organ. In the present study, mouse placental samples from Embryonic Day (E) 7.5 to E17.5 and human chorionic villi from the first and second trimester, as well as term pregnancy, were analysed for NUCB2/nesfatin-1 expression by immunohistochemistry with an antiserum that recognised both NUCB2 and nesfatin-1. From E7.5 to E9.5, NUCB2/nesfatin-1 was expressed in the ectoplacental cone, then parietal trophoblast giant cells and early spongiotrophoblast. At E10.5–12.5, NUCB2/nesfatin-1 expression became detectable in the developing labyrinth. From E12.5 and onwards, NUCB2/nesfatin-1 was expressed in the glycogen trophoblast cells, as well as highly expressed in syncytiotrophoblast, sinusoidal trophoblast giant cells and fetal capillary endothelial cells of the labyrinth. In all trimesters of human pregnancy, NUCB2/nesfatin-1 was highly expressed in syncytiotrophoblast. In addition, there was a significant increase in NUCB2 expression in human primary trophoblast cells induced to syncytialise. Thus, the haemochorial mammalian placenta is a novel source of NUCB2/nesfatin-1 and likely a site of its action, with potential roles in glucose homeostasis and/or nutrient sensing.

The thermogenic effect of nesfatin-1 requires recruitment of the melanocortin system

Nesfatin-1 is a bioactive polypeptide expressed both in the brain and peripheral tissues and involved in the control of energy balance by reducing food intake. Central administration of nesfatin-1 significantly increases energy expenditure, as demonstrated by a higher dry heat loss; yet, the mechanisms underlying the thermogenic effect of central nesfatin-1 remain unknown. Therefore, in this study, we sought to investigate whether the increase in energy expenditure induced by nesfatin-1 is mediated by the central melanocortin pathway, which was previously reported to mediate central nesfatin-1´s effects on feeding and numerous other physiological functions. With the application of direct calorimetry, we found that intracerebroventricular nesfatin-1 (25 pmol) treatment increased dry heat loss and that this effect was fully blocked by simultaneous administration of an equimolar dose of the melanocortin 3/4 receptor antagonist, SHU9119. Interestingly, the nesfatin-1-induced increase in dry heat loss was positively correlated with body weight loss. In addition, as assessed with thermal imaging, intracerebroventricular nesfatin-1 (100 pmol) increased interscapular brown adipose tissue (iBAT) as well as tail temperature, suggesting increased heat production in the iBAT and heat dissipation over the tail surface. Finally, nesfatin-1 upregulated pro-opiomelanocortin and melanocortin 3 receptor mRNA expression in the hypothalamus, accompanied by a significant increase in iodothyronine deiodinase 2 and by a nonsignificant increase in uncoupling protein 1 and peroxisome proliferator-activated receptor gamma coactivator-1 alpha mRNA in the iBAT. Overall, we clearly demonstrate that nesfatin-1 requires the activation of the central melanocortin system to increase iBAT thermogenesis and, in turn, overall energy expenditure.

Functional Relationship between Arterial Tissue and Perivascular Adipose Tissue in Metabolic Syndrome

Metabolic syndrome is a complex of disorders that includes visceral obesity, insulin resistance, hypertension, and dyslipidemia. It is characterized by an increased risk for serious cardiovascular events. Adipocytes are now recognized to contribute to the development of cardiovascular complications in metabolic syndrome via the release of several bioactive substances (adipocytokines). Obesity induces an increase in the volume of perivascular adipose tissue (PVAT), which is located outside the blood vessels. In recent years, PVAT has been reported to produce/release vasoactive adipocytokines. Thus, PVAT can modulate vasomotor function by releasing vasorelaxing/vasocontracting factors, resulting in the development of cardiovascular disease due to metabolic syndrome. By using animal models (SHR/NDmcr-cp rats, SHRSP.Z-Lepr(fa)/IzmDmcr rats, and B6.BKS (D)-Lepr(fa)/J mice), we have demonstrated that chronic oxidative-nitrative stress is closely linked to the development of vascular dysfunction in response to nitric oxide (NO) in resistant arteries with increasing age/exposure to metabolic abnormalities. Further, our recent findings have led us to believe that PVAT helps in the regulation of vasodilation to compensate for the impaired vasodilation observed in pathophysiological conditions in the mesenteric arteries of SHRSP.Z-Lepr(fa)/IzmDmcr rats. However, a breakdown of the compensatory system occurs with long-term exposure to metabolic abnormalities. We propose the concept of the functional regulation of vascular tissue by PVAT in metabolic syndrome.

Pro-contractile effects of perivascular fat in health and disease

Perivascular adipose tissue (PVAT) is now recognized as an active player in vascular homeostasis. The expansion of PVAT in obesity and its possible role in vascular dysfunction have attracted much interest. In terms of the regulation of vascular tone and blood pressure, PVAT has been shown to release vasoactive mediators, for instance, angiotensin peptides, reactive oxygen species, chemokines and cytokines. The secretory profile of PVAT is altered by obesity, hypertension and other cardiovascular diseases, leading to an imbalance between its pro-contractile and anti-contractile effects. PVAT adipocytes represent an important source of the mediators, but infiltrating immune cells may become more important under conditions of hypoxia and inflammation. This review describes recent advances in the effects of PVAT on the regulation of vascular tone, highlighting the evidence for a pro-contractile action in health and disease. The role of the endothelium, vascular smooth muscle, immune cells and probably perivascular nerves in PVAT function is also discussed.

LINKED ARTICLES

This article is part of a themed section on Molecular Mechanisms Regulating Perivascular Adipose Tissue - Potential Pharmacological Targets? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.20/issuetoc.

Adipocytokine, progranulin, augments acetylcholine-induced nitric oxide-mediated relaxation through the increases of cGMP production in rat isolated mesenteric artery

AIM

Progranulin (PGRN) is a novel adipocytokine with anti-inflammatory effects in vascular cells. The aim of this study was to clarify the effects of PGRN on reactivity of isolated blood vessel.

METHODS

Isometric contraction of rat isolated superior mesenteric artery was measured.

RESULTS

Pre-treatment with PGRN (10-100 ng mL^-1 , 30 min) had no effect on noradrenaline- or 5-hydroxytriptamine-induced contraction. On the other hand, pre-treatment with PGRN (100 ng mL^-1 ) augmented acetylcholine (ACh; 30 nm)-induced endothelium-dependent relaxation. Pre-treatment with PGRN (100 ng mL^-1 ) augmented ACh (10 μm)-induced nitric oxide (NO)-mediated relaxation in the presence of indomethacin (10 μm), a cyclooxygenase inhibitor, and tetraethyl ammonium (10 mm), a non-selective potassium channel blocker. In contrast, pre-treatment with PGRN (100 ng mL^-1 ) had no effect on ACh-induced endothelium-derived hyperpolarizing factor-mediated relaxation. Pre-treatment with PGRN (100 ng mL^-1 ) had no effect on ACh (10 μm, 1 min)-induced endothelial NO synthase phosphorylation (at Ser1177) as determined by Western blotting. Pre-treatment with PGRN (100 ng mL^-1 ) augmented an NO donor, sodium nitroprusside (SNP; 30 nm-1 μm)- but not a membrane-permeable cGMP analogue, 8-bromo-cGMP-induced relaxation. In the presence of 3-isobutyl-1-methylxanthine (100 μm), a phosphodiesterase inhibitor, pre-treatment with PGRN (100 ng mL^-1 ) increased SNP (30 nm, 5 min)-induced cGMP production as determined by enzyme immunoassay.

CONCLUSION

We for the first time demonstrate that PGRN augments ACh-induced NO-mediated relaxation through the increases of cGMP production in smooth muscle. These results indicate PGRN as a possible pharmacotherapeutic target against cardiovascular diseases including obesity-related hypertension.

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.

Ultrasonography reveals in vivo dose-dependent inhibition of end systolic and diastolic volumes, heart rate and cardiac output by nesfatin-1 in zebrafish

Nesfatin-1 is an 82 amino acid peptide that inhibits food intake in rodents and fish. While endogenous nesfatin-1, and its role in the regulation of food intake and hormone secretion has been reported in fish, information on cardiovascular functions of nesfatin-1 in fish is in its infancy. We hypothesized that cardiac NUCB2 expression is meal responsive and nesfatin-1 is a cardioregulatory peptide in zebrafish. NUCB2/nesfatin-1 like immunoreactivity was detected in zebrafish cardiomyocytes. Real-time quantitative PCR analysis found that the cardiac expression of NUCB2A mRNA in unfed fish decreased at 1h post-regular feeding time. Food deprivation for 7days did not change NUCB2A mRNA expression. However, NUCB2B mRNA expression was increased in the heart of zebrafish after a 7-day food deprivation. Ultrasonography of zebrafish heart at 15min post-intraperitoneal injection of nesfatin-1 (250 and 500ng/g body weight) showed a dose-dependent inhibition of end diastolic and end systolic volumes. A dose dependent decrease in heart rate and cardiac output was observed in zebrafish that received nesfatin-1, but no changes in stroke volume were found. Nesfatin-1 treatment caused a significant increase in the expression of Atp2a2a mRNA encoding the calcium-handling pump, SERCA2a, while it had no effects on the expression of calcium handling protein RyR1b encoding mRNA. Our data support cardiosuppressive effects of nesfatin-1 in zebrafish, and reveals energy availability as one determinant of cardiac NUCB2 mRNA expression.

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.

Visceral adipose tissue-derived serine protease inhibitor augments acetylcholine-induced relaxation via the inhibition of acetylcholine esterase activity in rat isolated mesenteric artery

AIM

Visceral adipose tissue-derived serine protease inhibitor (vaspin) is an adipocytokine with insulin-sensitizing activity originally identified in visceral adipose tissues of obesity-related type II diabetic rats. We previously showed that vaspin inhibits vascular cell migration and apoptosis as well as inflammatory responses, which are crucial for the development of hypertension. However, little is known about the effects of vaspin on vascular reactivity. The aim of this study was thus to explore the effects of vaspin on contraction and relaxation of isolated blood vessel.

METHODS

After mesenteric arteries were isolated from male Wistar rats, the effects of pretreatment with vaspin (3 ng mL(-1) , 30 min) on concentration-contraction and concentration-relaxation relationships for each agent were examined. The effects of vaspin on acetylcholine (ACh)-induced phosphorylation of endothelial nitric oxide (NO) synthase (eNOS) and ACh esterase (AChE) activity were also examined using Western blotting and colorimetric method respectively.

RESULTS

Vaspin did not affect noradrenaline- or 5-hydroxytryptamine-induced contraction. In contrast, vaspin augmented ACh- but not histamine-, A23187- or carbachol-induced NO-mediated relaxation. Vaspin significantly increased ACh-induced eNOS phosphorylation and inhibited AChE activity.

CONCLUSION

We for the first time demonstrate that vaspin augments the ACh-induced NO-mediated endothelium-dependent relaxation via the inhibition of AChE activity.

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.

The role of centrally injected nesfatin-1 on cardiovascular regulation in normotensive and hypotensive rats

This study investigated the cardiovascular effects of nesfatin-1 in normotensive rats and animals subjected to hypotensive hemorrhage. Hemorrhagic hypotension was induced by withdrawal 2 mL blood/100 g body weight over a period of 10 min. Acute hemorrhage led to a severe and long-lasting decrease in mean arterial pressure (MAP) and heart rate (HR). Intracerebroventricularly (i.c.v.) administered nesfatin-1 (100 pmol) increased MAP in both normotensive and hemorrhaged rats. Nesfatin-1 also caused bradycardia in normotensive and tachycardia in hemorrhaged rats. Centrally injected nesfatin-1 (100 pmol, i.c.v.) also increased plasma catecholamine, vasopressin and renin concentrations in control animals and potentiated the rise in all three cardiovascular mediators produced by hemorrhage. These findings indicate that centrally administered nesfatin-1 causes a pressor response in conscious normotensive and hemorrhaged rats and suggest that enhanced sympathetic activity and elevated vasopressin and renin concentrations mediate the cardiovascular effects of the peptide.

Eukaryotic elongation factor 2 kinase mediates monocrotaline-induced pulmonary arterial hypertension via reactive oxygen species-dependent vascular remodeling

Pulmonary arterial (PA) hypertension (PAH) is a progressive and lethal disease that is caused by increased vascular contractile reactivity and structural remodeling. These changes contribute to increasing pulmonary peripheral vascular resistance, finally leading to right heart failure and death. Eukaryotic elongation factor 2 kinase (eEF2K) is a Ca2+/calmodulin-dependent protein kinase. We previously revealed that eEF2K protein increases in the mesenteric artery from spontaneously hypertensive rats and partly mediates the development of hypertension via a promotion of ROS-dependent vascular inflammatory responses and proliferation and migration of vascular smooth muscle cells. However, a role of eEF2K in the pathogenesis of PAH is unknown. In the present study, we tested the hypothesis that eEF2K may be involved in the pathogenesis of PAH. PAH was induced by a single intraperitoneal injection of monocrotaline (MCT; 60 mg/kg) to rats. A specific eEF2K inhibitor, A-484954 (2.5 mg·kg−1·day−1), was intraperitoneally injected for 14 days. Long-term A-484954 treatment inhibited MCT-induced increased PA pressure. It was revealed that A-484954 inhibited MCT-induced PA hypertrophy and fibrosis but not impairment of endothelium-dependent and -independent relaxation. Furthermore, A-484954 inhibited MCT-induced NADPH oxidase-1 expression and ROS generation as well as matrix metalloproteinase-2 activation. In conclusion, the present results suggest that eEF2K at least partly mediates MCT-induced PAH via stimulation of vascular structural remodeling perhaps through NADPH oxidase-1/ROS/matrix metalloproteinase-2 pathway.

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 short review of adipokines, smooth muscle and uterine contractility

Obesity is a major health problem worldwide. The prevalence of obesity is increasing in both developed and developing countries. In the UK, for example, 60% of adults are overweight and 25% are obese. Obesity is associated with many pathological complications including respiratory, cardiovascular and endocrine, but it also affects fertility and is associated with many reproductive complications. This has led us and others to investigate links between women with high BMI, pregnancy outcome and uterine function. These studies in turn have led investigators to ask how obesity can have such an impact on reproduction and, as part of this, to consider the role of the adipokines released from adipose tissues. Our focus in this short review is on adipokines and myometrial activity, and for completeness we overview their effects on other smooth muscles. To date four adipokines (leptin, visfatin, apelin and ghrelin) have been investigated and all affect myometrial contractility, but some more potently than others. We consider the possible mechanisms involved in how adipokines may modify uterine contractility, and discuss the potential impact on labor and delivery.

Perivascular fat, AMP-activated protein kinase and vascular diseases

Perivascular adipose tissue (PVAT) is an active endocrine and paracrine organ that modulates vascular function, with implications for the pathophysiology of cardiovascular disease (CVD). Adipocytes and stromal cells contained within PVAT produce mediators (adipokines, cytokines, reactive oxygen species and gaseous compounds) with a range of paracrine effects modulating vascular smooth muscle cell contraction, proliferation and migration. However, the modulatory effect of PVAT on the vascular system in diseases, such as obesity, hypertension and atherosclerosis, remains poorly characterized. AMP-activated protein kinase (AMPK) regulates adipocyte metabolism, adipose biology and vascular function, and hence may be a potential therapeutic target for metabolic disorders such as type 2 diabetes mellitus (T2DM) and the vascular complications associated with obesity and T2DM. The role of AMPK in PVAT or the actions of PVAT have yet to be established, however. Activation of AMPK by pharmacological agents, such as metformin and thiazolidinediones, may modulate the activity of PVAT surrounding blood vessels and thereby contribute to their beneficial effect in cardiometabolic diseases. This review will provide a current perspective on how PVAT may influence vascular function via AMPK. We will also attempt to demonstrate how modulating AMPK activity using pharmacological agents could be exploited therapeutically to treat cardiometabolic diseases.

Decreased levels of serum nesfatin-1 in patients with obstructive sleep apnea syndrome

PURPOSE

Recent evidences suggest that inflammation is involved in the mechanism of obstructive sleep apnea syndrome (OSAS). Nesfatin-1, recently identified as the satiety regulator, is implicated to possess an anti-inflammatory effect. The aim of our study is to investigate whether serum levels of nesfatin-1 are associated with the presence and severity of OSAS.

METHODS

A total of 196 patients with OSAS and 104 healthy subjects were enrolled in this study. Serum levels of nesfatin-1 were measured by enzyme-linked immunosorbent assay.

RESULTS

OSAS patients showed significantly reduced levels of serum nesfatin-1 levels than healthy controls. Multivariable logistic regression analysis indicates that serum nesfatin-1 levels were inversely associated with the presence of OSAS (odds ration (OR) 0.003, 95% confidence interval (CI) 0.001 to 0.017; P < 0.001). Serum levels of nesfatin-1 were significantly decreased in severe OSAS patients compared with mild and moderate OSAS patients. Spearman correlation analysis showed that serum nesfatin-1 levels were inversely correlated with the severity of OSAS. In addition, Spearman correlation analysis showed that serum nesfatin-1 levels were negatively correlated with body mass index (BMI) (r = -0.299, P < 0.001), waist-hip ratio (WHR) (r = -0.277, P < 0.001), homeostasis model assessment of insulin resistance (HOMA-IR) (r = -0.338, P < 0.001), and apnea-hypopnea index (AHI) (r = -0.248, P < 0.001) in patients with OSAS.

CONCLUSIONS

Decreased serum nesfatin-1 levels are associated with the presence and severity of OSAS.

Decreased serum nesfatin-1 levels in endometriosis

OBJECTIVE(S)

To investigate serum nesfatin-1 levels in endometriosis patients.

STUDY DESIGN

Twenty-five women who were laparoscopically and histopathologically diagnosed with endometriosis (endometriosis group) and 25 women without any pelvic pathology detected by laparoscopy (control group) were enrolled in the study. Serum nesfatin-1 levels were compared between the two groups before and after adjustment for body mass index (BMI) and age.

RESULTS

Patients in the endometriosis group had lower BMI than those in the control group (22.3 ± 4.8 kg/m(2) vs. 25.8 ± 4.2 kg/m(2), p=0.009). There was no statistically significant correlation between BMI and serum nesfatin-1 levels (p=0.870). Serum nesfatin-1 level was statistically significantly lower in the endometriosis group than in the control group (7.2 ± 1.3 pg/ml vs. 10.6 ± 2.8 pg/ml, p=0.0001). This result did not change after the adjustment for BMI and age.

CONCLUSION(S)

Serum levels of nesfatin-1 are decreased in endometriosis patients but its exact role in the etiopathogenesis of endometriosis remains to be clarified.

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.

Nesfatin-1 in human and murine cardiomyocytes: synthesis, secretion, and mobilization of GLUT-4

Nesfatin-1, a satiety-inducing peptide identified in hypothalamic regions that regulate energy balance, is an integral regulator of energy homeostasis and a putative glucose-dependent insulin coadjuvant. We investigated its production by human cardiomyocytes and its effects on glucose uptake, in the main cardiac glucose transporter GLUT-4 and in intracellular signaling. Quantitative RT-PCR, Western blots, confocal immunofluorescence microscopy, and ELISA of human and murine cardiomyocytes and/or cardiac tissue showed that cardiomyocytes can synthesize and secrete nesfatin-1. Confocal microscopy of cultured cardiomyocytes after GLUT-4 labeling showed that nesfatin-1 mobilizes this glucose transporter to cell peripherals. The rate of 2-deoxy-D-[(3)H]glucose incorporation demonstrated that nesfatin-1 induces glucose uptake by HL-1 cells and cultured cardiomyocytes. Nesfatin-1 induced dose- and time-dependent increases in the phosphorylation of ERK1/2, AKT, and AS160. In murine and human cardiac tissue, nesfatin-1 levels varied with diet and coronary health. In conclusion, human and murine cardiomyocytes can synthesize and secrete nesfatin-1, which is able to induce glucose uptake and the mobilization of the glucose transporter GLUT-4 in these cells. Nesfatin-1 cardiac levels are regulated by diet and coronary health.

Increased serum levels and chondrocyte expression of nesfatin-1 in patients with osteoarthritis and its relation with BMI, hsCRP, and IL-18

Background. Adipokines have been proved to relate with osteoarthritis (OA). As a recently discovered adipokine, nesfatin-1 relationship with OA has not been reported. Aim. To determine the levels of nesfatin-1 in serum and synovial fluid (SF) from patients with and without OA; to examine the correlation between nesfatin-1 levels and high sensitivity C-reactive protein (hsCRP), Type IIA Collagen N Propeptide (PIIANP), and IL-18 (interleukin-18) levels in serum or synovial fluid. Methods. Serum and SF were collected from knee OA patients and healthy persons, respectively. Five articular tissues were obtained during TKR for immunohistochemistry (IHC). Nesfatin-1 levels, hsCRP, PIIANP, and IL-18 in serum and SF were analyzed by enzyme-linked immunosorbent assay (ELISA). Results. Nesfatin-1 gene was expressed in OA-affected articular cartilage. OA serum contained significantly higher levels of nesfatin-1, as compared to serum from healthy controls (P < 0.05), and nesfatin-1 levels in OA serum exceeded those in paired SF samples (P < 0.001). Significant correlation was found between serum nesfatin-1 and hsCRP levels in OA patients (r = 0.593, P = 0.00005) and also synovial nesfatin-1 and IL-18 levels (r = 0.560, P = 0.0017). Conclusion. Nesfatin-1 is present in articular tissues and may contribute to the physiopathologic changes in OA. Nesfatin-1, accompanied with hsCRP and IL-18, could be new molecular makers to speculate OA progression.

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.