Plasma visfatin/nicotinamide phosphoribosyltransferase levels in hypertensive elderly – results from the PolSenior substudy

Role of major adipokines in hypertension: A literature review

The incidence and prevalence of hypertension are increasing as a consequence of the obesity epidemic. Adipocytes and their variety of factors make contributions to the long-term regulation of blood pressure. The pathophysiologic states of hypertension, including obesity, are regulated by the production of adipocyte-derived factors. Increased body mass index was closely linked to elevated blood pressure. Mostly the hypertensive subjects were obese as well as overweight. There are numerous adipokines, however, this review article only focuses on the major adipokines including chemerin, visfatin, retinol-binding protein 4, plasminogen activator inhibitor-1, monocyte chemotactic protein-1, omentin-1, lipocalin-2, vaspin, progranulin, complement c1q tumor necrosis factor-related protein, and nesfatin-1 role in the pathogenesis of hypertension. This review article concludes the significant association of major adipokines in the pathogenesis of hypertensives. New research should be focused on other newly reported adipokine roles in hypertensive subjects and the management of these adipokines in hypertensive subjects. The discovery of this information could result in the creation of antihypertensive medications, particularly those that focus on obesity-related hypertension.

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/eNampt induces endothelial dysfunction in vivo: a role for Toll-Like Receptor 4 and NLRP3 inflammasome

Visfatin/extracellular-nicotinamide-phosphoribosyltranferase-(eNampt) is a multifaceted adipokine enhanced in type-2-diabetes and obesity. Visfatin/eNampt cause in vitro endothelial dysfunction and vascular inflammation, although whether the same effects are achieved in vivo is unknown. Toll-like receptor-4 (TLR4), a main surface pattern recognition receptor of innate immune system is a potential target for visfatin/eNampt. We studied its capacity to generate vascular dysfunction in vivo, focusing on TLR4 role and downstream activation of nod-like-receptor-protein-3 (NLRP3)-inflammasome. 4 month-old C57BL/6 mice were exposed to 7 days infusion of visfatin/eNampt, alone or together with FK 866 (Nampt enzymatic inhibitor), CLI 095 (TLR4 blocker), MCC 950 (NLRP3-inflammasome inhibitor), or anakinra (interleukin(IL)-1-receptor antagonist). Endothelial dysfunction was tested in isolated microvessels. In human umbilical endothelial cells (HUVEC), proteins related to the NLRP3-inflammasome phosphorylated p-65, NLRP3, caspase-1, pro-IL-1β, and mature IL-1β were determined by Western blot, while the inflammasome related apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC-specks) was studied by immunofluorescence. Impaired endothelium-dependent relaxations were observed in isolated mesenteric microvessels from visfatin/eNampt-infused mice. This effect was attenuated by co-treatment with FK 866 or CLI 095, supporting a role for Nampt enzymatic activity and TLR4 activation. Moreover, cultured HUVEC exposed to visfatin/eNampt showed higher expression and activation of NLRP3-inflammasome. Again, this effect relied on Nampt enzymatic activity and TLR4 activation, and it was abrogated by the inflammasome assembly blockade with MCC 950. The endothelial dysfunction evoked by visfatin/eNampt infusion in vivo was also sensitive to both MCC 950 and anakinra treatments, suggesting that the NLRP3-inflammasome-driven tissular release of IL-1β is the final mediator of endothelial damage. We conclude that Visfatin/eNampt produces in vivo vascular dysfunction in mice by a Nampt-dependent TLR4-mediated pathway, involving NLRP3-inflammasome and paracrine IL-1β. Thus, those targets may become therapeutic strategies for attenuating the adipokine-mediated vascular dysfunction associated to obesity and/or type-2-diabetes.

Visfatin induces the apoptosis of endothelial progenitor cells via the induction of pro-inflammatory mediators through the NF-κB pathway

Endothelial progenitor cells (EPCs) are an independent factor predicting cardiovascular events. Visfatin plays an important role in the pathogenesis of various metabolic disorders. In this study, we examined the effects of visfatin on the apoptosis of EPCs and the mechanisms underlying these effects. Cultured EPCs pre-treated with various concentrations of visfatin, FK866 (visfatin inhibitor) and BAY11-7085 [referred to as BAY11; nuclear factor-κB (NF-κB) inhibitor] were used to investigate the association between visfatin and EPC apoptosis. Following treatment with visfatin for 48 h, the EPCs exhibited a dose-dependent increase in apoptosis and an upregulated expression of Bax, caspase-3 and NF-κB at both the mRNA and protein level, and a decreased protein expression of Bcl-2. Compared with the untreated control group, the increase in EPC apoptosis, as well as in Bax and caspase-3 expression was significant following treatment with 150 ng/ml visfatin, which also induced a dose-dependent and significant increase in the protein expression of interleukin-6 (IL-6) and intercellular adhesion molecule-1 (ICAM-1). All the visfatin-induced effects were suppressed by pre-treatment with FK866. Pre-incubation of the EPCs with BAY11 for 1 h followed by treatment with visfatin (150 ng/ml) for 48 h also abolished visfatin-induced apoptosis; it also abolished the promoting effects of visfatin on the expression of caspase-3, Bax, ICAM-1 and IL-6, and its suppressive effects on the protein expression of Bcl-2. On the whole, our data indicate that visfatin induces EPC apoptosis by increasing the expression of pro-inflammatory mediators partly through the regulation of NF-κB.

Genetic associations of the visfatin G-948T polymorphism with obesity-related metabolic traits in an Iranian population

Background:

Obesity is a global public health problem. Visfatin, as an adipocytokine, is coded by a gene known as nicotinamide phosphoribosyltransferase. So far, results were conflicted regarding correlations of visfatin with obesity and metabolic variables. The present study aimed to explore the association between G-948T polymorphism of visfatin gene with obesity and lipid profile in a nationally representative sample of Iranian population.

Materials and Methods:

In this case–control study, we assessed 129 randomly selected patients with obesity and 182 healthy normal weight controls from participants of Isfahan Healthy Heart Program. Genomic DNA was isolated from peripheral blood cells, and high-resolution melt polymerase chain reaction was performed to explore the presence of G-948T polymorphism.

Results:

T carriers “GT + TT” were statistically more frequent in the obese patients than the controls (P = 0.013; odds ratio = 1.9, 95% confidence interval = 1.1–3.1). The serum levels of total cholesterol and low-density lipoprotein cholesterol (LDL-C) were significantly different between T carriers and GG homozygote genotype (P = 0.03 and 0.02, respectively).

Conclusion:

We concluded that visfatin G-948T polymorphism was correlated with obesity, total cholesterol, and LDL-C levels in our population.

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.

The influence of frailty syndrome on medication adherence among elderly patients with hypertension

BACKGROUND

Hypertension affects about 80% of people older than 80 years; however, diagnosis and treatment are difficult because about 55% of them do not adhere to treatment recommendations due to low socioeconomic status, comorbidities, age, physical limitations, and frailty syndrome.

AIMS

The purposes of this study were to evaluate the influence of frailty on medication adherence among elderly hypertensive patients and to assess whether other factors influence adherence in this group of patients.

METHODS AND RESULTS

The study included 296 patients (mean age 68.8±8.0) divided into frail (n=198) and non-frail (n=98) groups. The Polish versions of the Tilburg Frailty Indicator (TFI) for frailty assessment and 8-item Morisky Medication Adherence Scale for adherence assessment were used. The frail patients had lower medication adherence in comparison to the non-frail subjects (6.60±1.89 vs 7.11±1.42; P=0.028). Spearman's rank correlation coefficients showed that significant determinants with negative influence on the level of adherence were physical (rho =-0.117), psychological (rho =-0.183), and social domain (rho =-0.163) of TFI as well as the total score of the questionnaire (rho =-0.183). However, multiple regression analysis revealed that only knowledge about complications of untreated hypertension (β=0.395) and satisfaction with the home environment (β=0.897) were found to be independent stimulants of adherence level.

CONCLUSION

Frailty is highly prevalent among elderly hypertensive patients. Higher level of frailty among elderly patients can be considered as a determinant of lower adherence. However, social support and knowledge about complications of untreated hypertension are the most important independent determinants of adherence to pharmacological treatment.

The relationship between circulating visfatin/nicotinamide phosphoribosyltransferase, obesity, inflammation and lipids profile in elderly population, determined by structural equation modeling

BACKGROUND

The available literature suggests that circulating visfatin/Nicotinamide Phosphoribosyltransferase (NAMPT) level variability in humans is related to obesity, insulin resistance, inflammation, and lipid profile. The aim of the study was to assess the relationship between circulating visfatin/NAMPT, obesity, insulin resistance, inflammation, and lipid profile in a large population-based, elderly cohort, applying structural equation modeling.

MATERIALS AND METHODS

The analysis included 2983 elderly participants of the PolSenior study with assessed total blood count, fasting concentrations of lipids, glucose, insulin, hs-CRP, interleukin-6, and visfatin/NAMPT (by ELISA), and calculated HOMA-IR.

RESULTS

The circulating visfatin/NAMPT levels were higher in obese compared to normal weight subjects, in those with hs-CRP above 3 mg/L, with low serum HDL cholesterol, and in insulin resistant subjects. Based on results of the exploratory factor analysis, a baseline model of mutual relationship between four latent and measured variables was created and a final model was developed by maintaining only two significant categories. The important variables for 'latent inflammation' proved to be hs-CRP and IL-6 serum levels. In the case of 'nutritional status', important variables were BMI, waist circumference, and to a lesser extent insulin resistance. Additionally, the residual correlation between those two constructs was also statistically significant.

CONCLUSION

The structural equation modeling provided support for the existence of a link between nutritional status, inflammation and circulating visfatin/NAMPT level. This indicates that circulating visfatin/NAMPT can be considered as a novel surrogate marker of systemic inflammation associated with fat depot, especially visceral, in the elderly population.

Apelin and Visfatin Plasma Levels in Healthy Individuals With High Normal Blood Pressure

BACKGROUND

High normal blood pressure (BP; 130-139/85-89 mm Hg) is related with increased cardiovascular (CV) risk compared to normal BP (120-129/80-84 mm Hg) or/and optimal BP (<120/80 mm Hg). Low apelin plasma levels have been associated with arterial hypertension and atherosclerosis, while high visfatin plasma levels may promote vascular inflammation and atherosclerotic plaque destabilization and have been evaluated as a marker for identifying stages of essential hypertension. We sought to compare the apelin and visfatin plasma levels between subjects with high normal BP and subjects with normal or optimal BP matched for age, gender, smoking, and body mass index (BMI).

METHODS

Twenty-five subjects with high normal BP (office BP 136±3/88±2 mm Hg, age 57±4 years, 76% males, 32% smokers, BMI 24.0±1.7 kg/m2) and 35 subjects with normal or optimal BP (office BP 118±2/78±2 mm Hg, age 55±7 years, 63% males, 29% smokers, BMI 23.2±1.4 kg/m2) were studied. The apelin and visfatin plasma levels were determined with the enzyme-linked immunosorbent assay.

RESULTS

Compared to normal or optimal BP subjects, apelin levels were significantly lower (205±108 vs. 325±152 pg/ml, P < 0.001) and visfatin levels significantly higher (11.0±2.0 vs. 7.2±0.9 ng/ml, P = 0.002) in high normal BP subjects. No significant differences were found between the 2 groups (P = NS) regarding the basic clinical characteristics, the glycemic/lipid profile, and the renal function parameters.

CONCLUSIONS

The emerging, from the present study, data raise the hypothesis that lower apelin and higher visfatin plasma levels in high normal BP subjects compared to normal or optimal BP individuals could partially explain the higher CV risk of the high normal BP group.

Increased Circulating Visfatin Is Associated With Progression of Kidney Disease in Non-Diabetic Hypertensive Patients

BACKGROUD

Declining renal function is an independent risk factor for all-cause mortality in cardiovascular disease. Visfatin has been described as a marker of inflammation and endothelial dysfunction, but whether circulating visfatin levels are predictive to a subsequent decline in renal function remains unclear.

METHODS

In total, 200 nondiabetic, non-proteinuric hypertensive outpatients with initial serum creatinine (Scr) ≤1.5 mg/dl were enrolled. Plasma visfatin concentration and endothelial function estimated by brachial artery flow-mediated dilatation (FMD) were determined in the study subjects. The primary endpoints were the occurrence of renal events including doubling of Scr, 25% loss of glomerular filtration rate (GFR) from baseline values, and the occurrence of end-stage renal disease during follow-up.

RESULTS

The mean annual rate of GFR decline (ΔGFR/y) was -1.26±2.76 ml/min/1.73 m(2) per year during follow-up (8.6±2.5 years). At baseline, plasma visfatin was negatively correlated with estimated GFR. In longitudinal analysis, the ΔGFR/y was correlated with visfatin, baseline GFR, FMD, systolic blood pressure, and fasting blood glucose (FBG). Multivariate analysis indicated that increased visfatin (r = -0.331, P <0.001), baseline GFR (r = -0.234, P = 0.001), FMD (r = 0.163, P = 0.015), and FBG (r = -0.160, P = 0.015) are independent predictors of ΔeGFR/y. Cox regression model analysis showed that visfatin (hazard ratio (HR), 1.09; 95% confidence interval (CI), 1.05-1.13, P <0.001), FBG (HR, 1.01; 95% CI, 1.00-1.02, P = 0.020), and FMD (HR, 0.87; 95% CI, 0.76-1.00, P = 0.049) were independently associated with the risk of developing future renal events.

CONCLUSIONS

Increased circulating visfatin are associated with subsequent decline in renal function in nondiabetic hypertensive patients.