Plasma visfatin levels in young male patients with uncomplicated and newly diagnosed hypertension

Obesity, Adipose Tissue and Vascular Dysfunction

Cardiovascular diseases are the leading cause of death worldwide. Overweight and obesity are strongly associated with comorbidities such as hypertension and insulin resistance, which collectively contribute to the development of cardiovascular diseases and resultant morbidity and mortality. Forty-two percent of adults in the United States are obese, and a total of 1.9 billion adults worldwide are overweight or obese. These alarming numbers, which continue to climb, represent a major health and economic burden. Adipose tissue is a highly dynamic organ that can be classified based on the cellular composition of different depots and their distinct anatomical localization. Massive expansion and remodeling of adipose tissue during obesity differentially affects specific adipose tissue depots and significantly contributes to vascular dysfunction and cardiovascular diseases. Visceral adipose tissue accumulation results in increased immune cell infiltration and secretion of vasoconstrictor mediators, whereas expansion of subcutaneous adipose tissue is less harmful. Therefore, fat distribution more than overall body weight is a key determinant of the risk for cardiovascular diseases. Thermogenic brown and beige adipose tissue, in contrast to white adipose tissue, is associated with beneficial effects on the vasculature. The relationship between the type of adipose tissue and its influence on vascular function becomes particularly evident in the context of the heterogenous phenotype of perivascular adipose tissue that is strongly location dependent. In this review, we address the abnormal remodeling of specific adipose tissue depots during obesity and how this critically contributes to the development of hypertension, endothelial dysfunction, and vascular stiffness. We also discuss the local and systemic roles of adipose tissue derived secreted factors and increased systemic inflammation during obesity and highlight their detrimental impact on cardiovascular health.

Association between Tumor Prognosis Marker Visfatin and Proinflammatory Cytokines in Hypertensive Patients

Visfatin has been reported as a risk factor and a potential diagnostic marker in cancer. It is an adipokine, secreted by visceral fat and associated with the pathogenesis of arterial hypertension. We investigated the circulatory levels of visfatin in hypertensive patients with hypertriglyceridemia, which are the risk factors for various cancers and its association with proinflammatory cytokines. A total of 81 (male/female: 33/48) subjects with or without hypertension were enrolled for this study. Group 1 was normotensive, Group 2 hypertensive, and Group 3 with hypertension with hypertriglyceridemia. Data on anthropometric and biochemical data were recorded. Plasma visfatin levels were measured using an ELISA kit. The plasma inflammatory cytokines were estimated using a multiplex bead-based assay. The results revealed that the hypertension with hypertriglyceridemia group has the highest levels of visfatin compared to the hypertension and control groups with a significant difference (p < 0.001). Besides, circulatory visfatin showed the strongest possible correlation with proinflammatory cytokines among hypertensive patients with hypertriglyceridemia. We found a positive correlation between visfatin and diastolic blood pressure as well as high-density lipoproteins. In conclusion, the outcomes of the present study demonstrate that plasma visfatin levels were found to be elevated in hypertensive patients with hypertriglyceridemia and associated with proinflammatory cytokines. Since hypertension has been documented as the most common comorbidity observed in cancer patients, visfatin may be a novel potential therapeutic target for hypertension in cancer patients and survivors.

Visfatin: An emerging adipocytokine bridging the gap in the evolution of cardiovascular diseases

Visfatin/nicotinamide phosphoribosyltransferase (NAMPT) is an adipokine expressed predominately in visceral fat tissues. High circulating levels of visfatin/NAMPT have been implicated in vascular remodeling, vascular inflammation, and atherosclerosis, all of which pose increased risks of cardiovascular events. In this context, increased levels of visfatin have been correlated with several upregulated pro-inflammatory mediators, such as IL-1, IL-1Ra, IL-6, IL-8, and TNF-α. Furthermore, visfatin is associated with leukocyte recruitment by endothelial cells and the production of adhesion molecules such as vascular cell adhesion molecule 1, intercellular cell adhesion molecule 1, and E-selectin, which are well known to mediate the progression of atherosclerosis. Moreover, diverse angiogenic factors have been found to mediate visfatin-induced angiogenesis. These include matrix metalloproteinases, vascular endothelial growth factor, monocyte chemoattractant protein 1, and fibroblast growth factor 2. This review aims to provide a comprehensive overview of the pro-inflammatory and angiogenic actions of visfatin, with a focus on the pertinent signaling pathways whose dysregulation contributes to the pathogenesis of atherosclerosis. Most importantly, some hypotheses regarding the integration of the aforementioned factors with the plausible atherogenic effect of visfatin are put forth for consideration in future studies. The pharmacotherapeutic potential of modulating visfatin's roles could be important in the management of cardiovascular disease, which continues to be the leading cause of death worldwide.

Nasser S, Younis N, Bhagani H, Al-Dhaheri Y, Pintus G, Eid AA, El-Yazbi AF, Eid AH. Visfatin: A Possible Role in Cardiovasculo-Metabolic Disorders

Visfatin/NAMPT (nicotinamide phosphoribosyltransferase) is an adipocytokine with several intriguing properties. It was first identified as pre-B-cell colony-enhancing factor but turned out to possess enzymatic functions in nicotinamide adenine dinucleotide biosynthesis, with ubiquitous expression in skeletal muscles, liver, cardiomyocytes, and brain cells. Visfatin exists in an intracellular (iNAMPT) and extracellular (eNAMPT) form. Intracellularly, visfatin/iNAMPT plays a regulatory role in NAD⁺ biosynthesis and thereby affects many NAD-dependent proteins such as sirtuins, PARPs, MARTs and CD38/157. Extracellularly, visfatin is associated with many hormone-like signaling pathways and activates some intracellular signaling cascades. Importantly, eNAMPT has been associated with several metabolic disorders including obesity and type 1 and 2 diabetes. In this review, a brief overview about visfatin is presented with special emphasis on its relevance to metabolic diseases. Visfatin/NAMPT appears to be a unique molecule with clinical significance with a prospective promising diagnostic, prognostic, and therapeutic applications in many cardiovasculo-metabolic disorders.

Evaluation of Serum Biomarkers in Patients with Sarcoidosis: Can Visfatin Be a New Biomarker for Sarcoidosis?

OBJECTIVES

Sarcoidosis is a chronic systemic inflammatory disease that affects multiple organ systems. The role of biomarkers in the diagnosis and prognosis of sarcoidosis is increasing. Interest in the role of adipose tissue-mediated inflammation in the pathogenesis of inflammatory diseases has increased in recent years. Visfatin is a proinflammatory adipocytokine that has been studied for several inflammatory diseases such as diabetes mellitus, obesity, and metabolic syndrome. We aimed to assess serum visfatin levels in sarcoidosis and its relationship with other markers of inflammation such as C-reactive protein (CRP), angiotensin-converting enzyme (ACE) and erythrocyte sedimentation rate (ESR).

MATERIALS AND METHODS

We enrolled 59 patients with sarcoidosis and 21 healthy controls and measured plasma levels of visfatin, along with serum CRP, ESR, and ACE using ELISA (enzyme-linked immunosorbent assay) kits (Blue Gene Biotech, Shanghai, China).

RESULTS

Visfatin levels did not differ significantly between the patients and control subjects (29.9±15.8 ng/mL for patients and 23.93±16.73 ng/mL for controls, p=0.15), and there was no correlation between visfatin and serum CRP, ACE, or ESR in patients with sarcoidosis.

CONCLUSION

Visfatin is recently being discussed as a biomarker for inflammatory diseases in several studies, and results are controversial. In our study, no differences were found in the serum levels of visfatin between patients with sarcoidosis and the control group.

Visfatin levels are increased in patients with resistant hypertension and are correlated with left ventricular hypertrophy

OBJECTIVE

The aim of this study was to investigate the possible correlation of serum visfatin levels with resistant hypertension (RHT).

PATIENTS AND METHODS

Patients who had undergone ambulatory blood pressure measurements (ABPM) during the outpatient controls were prospectively recruited. Seventy-one patients with RHT and 94 patients with controlled hypertension (CHT) were included in the study. RHT was defined as 'uncontrolled blood pressure (BP) despite using three antihypertensive agents including a diuretic or need of four or more drugs to control BP'. The demographic properties, medications used, and laboratory parameters including visfatin levels were recorded.

RESULTS

In the RHT group, left ventricular mass index was significantly higher compared with the CHT group (108.13±26.86 vs. 89.46±24.09 g/m, P<0.01). High-sensitivity C-reactive protein and visfatin levels were significantly higher in the RHT group [4.0 (5.2) vs. 2.3 (3.0) mg/l, P<0.01, and 12.87±4.98 vs. 9.46±4.69 ng/ml, P<0.01, respectively] compared with the CHT group. In the multivariate linear regression model, visfatin level remained as an independent predictor for office systolic BP [B: 2.07, 95% confidence interval (CI): 1.17-2.98, P<0.01]; office diastolic BP (B: 0.71, 95% CI: 0.27-1.16, P<0.01); mean 24-h systolic ABPM (B: 1.46, 95% CI: 0.79-2.13, P<0.01); and mean 24-h diastolic ABPM (B: 0.88, 95% CI: 0.42-1.34, P<0.01) and was also correlated independently with left ventricular mass index (B: 3.13, 95% CI: 2.58-3.99, P<0.01).

CONCLUSION

In this cohort of RHT patients diagnosed with ABPM, we have found an independent correlation between higher visfatin levels and the presence of RHT and left ventricular hypertrophy.

Associations of Apelin, Visfatin, and Urinary 8-Isoprostane With Severe Hypertension in African Americans: The MH-GRID Study

BACKGROUND

Apelin is an adipokine directly associated with adiposity, insulin resistance, and decreased blood pressure. Urinary 8-isoprostane is a marker of chronic oxidative endothelial stress. Visfatin, an adipokine that acts by binding and activating the insulin receptor, has been associated with hypertension. As severe hypertension (SH) is highly prevalent among African Americans (AA), we aimed to assess the association of these biomarkers with SH status.

METHODS

A sample of 250 AA participants (134 normotensive controls and 116 with SH (including 98 treatment controlled, SCH: severe controlled hypertension, and 18 treatment resistant, SRH: severe resistant hypertension)) from the Minority Health Genomics and Translational Research Bio-Repository Database (MH-GRID) in metro Atlanta had blood analyzed for apelin and visfatin and urine for 8-isoprostane. T-tests, sex-specific age-adjusted correlation coefficients, and multivariable logistic regression models were used to assess the association of biomarkers with hypertensive status.

RESULTS

Levels of apelin and 8-isoprostane were not statistically different between controls and SCH or SRH. Statistically significant differences were present in levels of visfatin between controls (1.03±0.84 pg/ml), SCH (1.34±1.14 pg/ml), and SRH (1.59±0.85 pg/ml). After multivariable adjustment, categorization in the middle 2 quartiles of urinary 8-isoprostane were associated with SH. In similar models, categorization into the highest quartile of visfatin was associated with SH (odds ratio = 2.80; 95% confidence interval: 1.02-7.02). A continuous association of visfatin with SH was present.

CONCLUSION

In our community sample of AA, there were increased odds of SH with increased levels of urinary 8-isoprostane and visfatin, but not with apelin.

The effects of NAMPT haplotypes and metabolic risk factors on circulating visfatin/NAMPT levels in childhood obesity

OBJECTIVE

Polymorphisms in the NAMPT gene, which encodes the adipocytokine visfatin/nicotinamide phosphorybosil transferase (NAMPT), affect the circulating visfatin/NAMPT levels and are associated with obesity and cardiovascular diseases. However, no study has tested the hypothesis that NAMPT haplotypes could affect visfatin/NAMPT levels in case of childhood obesity. We investigated the effects of traditional metabolic risk factors (MRFs) and NAMPT polymorphisms T/C (rs1319501) and A/G (rs3801266) or haplotypes on visfatin/NAMPT levels in obese children and adolescents, and whether NAMPT polymorphisms and/or haplotypes are associated with susceptibility to childhood obesity.

METHODS

We studied 175 control, 99 obese and 82 obese with ⩾ 3 MRFs children and adolescents. Genotypes were determined by a Taqman allele discrimination assay and real-time PCR. The plasma visfatin/NAMPT level was measured using an enzyme immunoassay.

RESULTS

Obese children and adolescents with ⩾ 3 MRFs had higher plasma visfatin/NAMPT levels in comparison with control children and adolescents (P<0.05). Although positive associations were observed between visfatin/NAMPT and body mass index (rs = 0.157; P = 0.034) as well as visfatin/NAMPT and waist circumference (rs = 0.192; P = 0.011), visfatin/NAMPT and high-density lipoprotein cholesterol were inversely associated (rs = -0.162; P = 0.031). No significant differences in genotype, allele or haplotype frequency distributions for the studied polymorphisms were found when the three groups were compared. However, higher plasma visfatin/NAMPT levels were found in control and obese subjects carrying the GG genotype for the A/G (rs3801266) polymorphism (P<0.05) but not in obese children with ⩾ 3 MRFs. Moreover, control subjects carrying the 'T-G' haplotype showed higher plasma visfatin/NAMPT levels. NAMPT genotypes or haplotypes were not associated with childhood obesity.

CONCLUSIONS

Obesity in children with ⩾ 3 MRFs increases plasma visfatin/NAMPT levels, and this marker was associated with body mass index and waist circumference. The A/G polymorphism and NAMPT haplotypes affect plasma visfatin/NAMPT levels in controls but not in obese children with ⩾ 3 MRFs. These results suggest that obesity and MRFs are more influential than genetic polymorphisms in the determination of visfatin/NAMPT levels in obese children. Further research is necessary to explain why the GG genotype is not associated with increased visfatin/NAMPT levels in obese children with ⩾ 3 MRFs.

The effect of sodium restricted diet on plasma visfatin levels in hypertensive patients with visceral obesity

AIM/BACKGROUND

Experimental and clinical studies revealed contradictory data concerning the influence of renin-angiotensin-aldosterone (RAA) system activation on visfatin release. The aim of the present study was the assessment of the effect of dietary sodium restriction with RAA system activation on visfatin level in hypertensive and normotensive patients with visceral obesity.

METHODS

The study included 24 hypertensive patients with visceral obesity (12 women) and 22 normotensive subjects with visceral obesity (11 women) constituting the control group. Plasma renin activity, plasma insulin, aldosterone and visfatin levels were determined twice, on normal-salt diet after 6-8 h in recumbent position and the second time after 3 days of dietary sodium restriction and upright position for 2 h. Dietary compliance was controlled by 24 h natriuresis measurement.

RESULTS

Hypertensive patients had significantly higher plasma visfatin level than the control group [11.0 (8.5-13.5) vs. 6.8 (6.0-7.6) ng/ml, p=0.003]. Dietary sodium restriction and upright position caused significant increase in PRA and plasma aldosterone level in both groups. While, plasma visfatin level remained unaffected. In the combined group plasma visfatin levels correlated with BMI (r=0.398), waist circumference (r=0.391), glucose (r=0.328), insulin (r=0.663), HOMA-IR (r=0.698), triglycerides (r=0.500) and CRP (r=0.546) but not with percentage of fat mass, percentage of trunk fat, and blood pressure values.

CONCLUSIONS

1) Increased plasma visfatin concentration may play a significant role in the pathogenesis of hypertension in patients with visceral obesity. 2) RAA system activation by dietary sodium restriction and upright position has no effect on plasma visfatin levels in subjects with visceral obesity.

Adipokines and the cardiovascular system: mechanisms mediating health and disease

This review focuses on the role of adipokines in the maintenance of a healthy cardiovascular system, and the mechanisms by which these factors mediate the development of cardiovascular disease in obesity. Adipocytes are the major cell type comprising the adipose tissue. These cells secrete numerous factors, termed adipokines, into the blood, including adiponectin, leptin, resistin, chemerin, omentin, vaspin, and visfatin. Adipose tissue is a highly vascularised endocrine organ, and different adipose depots have distinct adipokine secretion profiles, which are altered with obesity. The ability of many adipokines to stimulate angiogenesis is crucial for adipose tissue expansion; however, excessive blood vessel growth is deleterious. As well, some adipokines induce inflammation, which promotes cardiovascular disease progression. We discuss how these 7 aforementioned adipokines act upon the various cardiovascular cell types (endothelial progenitor cells, endothelial cells, vascular smooth muscle cells, pericytes, cardiomyocytes, and cardiac fibroblasts), the direct effects of these actions, and their overall impact on the cardiovascular system. These were chosen, as these adipokines are secreted predominantly from adipocytes and have known effects on cardiovascular cells.

Visfatin and cardio-cerebro-vascular disease

Nicotinamide phosphoribosyltransferase is the rate-limiting enzyme that catalyzes the first step in the biosynthesis of nicotinamide adenine dinucleotide from nicotinamide. This protein was originally cloned as a putative pre-B cell colony-enhancing factor and also found to be a visceral fat-derived adipokine (visfatin). As a multifunctional protein, visfatin plays an important role in immunity, metabolism, aging, inflammation, and responses to stress. Visfatin also participates in several pathophysiological processes contributing to cardio-cerebro-vascular diseases, including hypertension, atherosclerosis, ischemic heart disease, and ischemic stroke. However, whether visfatin is a friend or a foe in these diseases remains uncertain. This brief review focuses on the current understanding of the complex role of visfatin in the cardio-cerebro-vascular system under normal and pathophysiological conditions.

Visfatin may be a novel marker for identifying stages of essential hypertension in advanced age patients

OBJECTIVE

Visfatin is a peptide that is secreted from visceral fat. It has been reported to be associated with inflammation and endothelial dysfunction. However, little is known about its function in hypertension. Therefore the aim of the present study was to evaluate visfatin levels in patients with hypertension.

METHODS

We studied forty-six newly diagnosed hypertensive patients and 30 healthy participants. In accordance with blood pressure levels reported in the JNC 7 guidelines, hypertensive patients were divided into 2 groups: stage 1 and stage 2. The control group was divided into 2 groups: normal and prehypertensive. Blood pressure (BP) measurements were obtained from each patient. Serum lipid profile, glucose and visfatin levels were measured.

RESULTS

The levels of fasting blood glucose (FBG), total cholesterol, triglyceride (TG), low density lipoprotein cholesterol (LDL-C), BMI, waist circumference were significantly higher in the patient group than those in control subjects (p<0.05). The mean visfatin level was significantly higher in hypertensive patients. In the prehypertensive group, the serum visfatin levels were also significantly higher than in participants with normal blood pressure (p:0.043). There was a significantly positive correlation with visfatin and systolic BP, diastolic BP.

CONCLUSION

We consider that visfatin may be a marker which may be used to illustrate damage even in prehypertensive stage caused by isolated essential HT.

Circulating and local visfatin/Nampt/PBEF levels in spontaneously hypertensive rats, stroke-prone spontaneously hypertensive rats and Wistar-Kyoto rats

Visfatin (also known as nicotinamide phosphoribosyltransferase and pre-B cell colony-enhancing factor) is a multifunctional protein. Visfatin has been reported to be involved in several biological processes in the cardiovascular system, . However, the role of visfatin in hypertension is still unclear. In this study, we examined the circulating and local adipose visfatin levels in spontaneously hypertensive rats (SHR), stroke-prone spontaneously hypertensive rats (SHR-SP), and in their normotensive control Wistar-Kyoto (WKY). SHR and SHR-SP rats exhibited lower body weight, lower fat tissue and hypolipidemia. No differences of serum visfatin levels were observed in SHR/SHR-SP and WKY. Serum visfatin levels did not correlate to serum glucose, lipids, insulin, and fat pad weights, but significantly correlated to weights of skeletal muscle. Visfatin expression in visceral fat tissue was slightly lower in SHR-SP compared with that in WKY. Moreover, there were no significant differences of visfatin expression in skeletal muscles among WKY, SHR and SHR-SP. Finally, visfatin protein was detected in L6 rat skeletal muscle cell culture medium, indicating that visfatin was secreted from skeletal muscle cells. Thus, our results may provide useful information for understanding the characteristic of visfatin in hypertensive models, and support the view that visfatin may be a myokine.

Plasma concentration of visfatin is a new surrogate marker of systemic inflammation in type 2 diabetic patients

It is not clear whether plasma visfatin level is related with systemic inflammation or diabetic nephropathy in diabetic patients. In this study, we investigated the relationship between plasma visfatin levels and systemic inflammation or diabetic nephropathy in type 2 diabetic patients. In addition, we examined the physiological action of visfatin in cultured adipocytes in diabetic condition. Plasma visfatin concentrations were significantly higher in the diabetic groups than in the controls. Plasma visfatin levels were positively correlated with systolic blood pressure, body weight, fasting blood glucose, plasma levels of MCP-1, urinary albumin excretion (UAE), and carotid intima-media thickness (IMT), and were inversely correlated with plasma adiponectin, and creatinine clearance. However, plasma visfatin concentrations did not show a significant relationship with HbA1C, BMI or HOMA-IR. Regression analysis showed that plasma levels of MCP-1 and UAE were only independent determinants of plasma visfatin concentration. In cultured adipocytes, high glucose and angiotensin II stimuli markedly increased visfatin synthesis. Exogenous visfatin treatment significantly decreased differentiation of adipocytes and increased NF-kappaB transcriptional activity and pro-inflammatory molecules in adipocytes. These findings suggest that visfatin synthesis is activated from adipose tissue in a diabetic environment, induces NF-kappaB activation and leads to activation of pro-inflammatory cytokines and systemic inflammation.

Body fat distribution has no effect on serum visfatin levels in healthy female subjects

Obesity is the presence of either abnormal absolute amount or relative proportion of body fat. Contrary to gluteal obesity, visceral obesity is associated with different metabolic alterations including insulin resistance (IR). A relatively new adipocytokine visfatin is shown to be expressed predominantly in visceral fat and exhibit insulin-mimicking effects in rodents. It is still unclear whether serum visfatin levels are associated with increased total or visceral fat mass in humans. The aim of our study was to investigate the relation between visfatin and obesity parameters namely body mass index (BMI) and waist circumference (WaC) and IR in healthy female subjects. Eighty one female subjects 20 years of age, having no diagnosis of glucose intolerance or diabetes, hypertension and dyslipidemia were chosen. The patients were divided into four groups according to their BMI and WaC values. Serum visfatin and HOMA-IR levels did not differ among groups. No correlation was detected between serum visfatin levels and obesity and metabolic parameters. In conclusion, we demonstrated that body fat distribution did not affect serum visfatin levels in healthy female subjects. Further studies are needed to clarify the exact factors influencing and determining serum visfatin levels and its clinical reflections.

Elevated peripheral visfatin levels in narcoleptic patients

OBJECTIVE

Narcolepsy is a severe sleep disorder that is characterized by excessive daytime sleepiness, cataplexies and a tendency towards obesity. Recent discoveries indicate that the major pathophysiology is a loss of hypocretin (orexin) producing neurons due to immunologically mediated degeneration. Visfatin is a recently described proinflammatory adipokine. It is identical to the immune modulating pre-B-cell colony enhancing factor (PBEF). Our study examines the hypothesis that visfatin levels are altered in narcoleptic patients.

METHODS

For the analysis, a total of n = 54 patients (n = 18 males and n = 36 females) with the diagnosis of narcolepsy according to DSM-IV and the International Classification of Sleep Disorders were examined (BMI mean 30.3+/-5.5, age mean 52.5+/-16.1 years). As a control group 39 unrelated (n = 12 males and n = 27 females) healthy volunteers with no sleep disorder according to DSM-IV were included (BMI mean 28.5+/-4.6, age mean 51.1+/-13.6 years). Peripheral visfatin levels were measured using a commercial enzyme immunoassay kit with a measurement range from 0.1-1000 ng/ml. Narcolepsy symptoms, severity and frequency of symptoms as well as the total duration of various aspects of the symptomatology were assessed by unstructured and structured clinical interviews in including the Stanford Center for Narcolepsy Sleep Inventory.

RESULTS

Circulating visfatin was found to be significantly increased in HLA DR2 positive narcoleptic patients compared to controls.

CONCLUSION

Taken together, our results add to the evidence of disturbed immunological regulation in patients with narcolepsy.