Deregulation of Soluble Adhesion Molecules in Resistant Hypertension and Its Role in Cardiovascular Remodeling

Abstract

Background: Resistant hypertension (RHTN) and target organ damage are linked to increased inflammatory biomarkers, which may regulate adhesion molecules, such as intracellular adhesion molecule-1 (ICAM-1); vascular cell adhesion molecule-1 (VCAM-1); and the platelet (P-selectin) and endothelial (E-selectin) selectins. We investigated a previously unknown relationship between soluble P-selectin (sP-selectin), E-selectin (sE-selectin), ICAM-1 (sICAM-1) and VCAM-1 (sVCAM-1) with RHTN and target organ damage.

Methods and Results: We included 110 subjects diagnosed for true RHTN and 112 mild-moderate hypertensive (HTN) patients. Blood pressure parameters, pulse wave velocity and left ventricular mass index (LVMI) were measured. Adhesion molecules were measured on ELISA. Both sP-selectin and sE-selectin were increased; in contrast, sICAM-1 was reduced in RHTN compared with HTN patients, while similar sVCAM-1 was noted in the groups. sP-selectin and sVCAM-1 were elevated in the presence of arterial stiffness (sP-selectin: 104±47 vs. 89±45 ng/ml, P<0.05; sVCAM-1: 1,189±411 vs. 1,060±412 ng/ml, P<0.05) and cardiac hypertrophy (sP-selectin: 105±51 vs. 88±43 ng/ml, P<0.05; sVCAM-1: 1,170±433 vs. 1,040±383 ng/ml, P<0.05) in all HTN patients. sP-selectin was associated with target organ damage after adjustment for age and BP. Apart from potential confounders, sE-selectin was a significant indicator of RHTN.

Conclusions: The adhesion molecule sP-selectin plays a role in cardiovascular damage, and sE-selectin in resistance to antihypertensive therapy. (Circ J 2016; 80: 1196–1201)

Resistant hypertension (RHTN) is characterized by persistent blood pressure (BP) elevation despite treatment with multiple drugs.¹ It is not only associated with poor BP control, but also with high prevalence of target organ damage, obesity, diabetes and atherosclerosis.^1,2 Despite efforts to implement a novel interventional therapy to improve BP control, results from randomized clinical trials have shown no benefit.^3,4

The pathophysiology of RHTN is poorly understood although several suggested mechanisms include (1) hyperactivity of both sympathetic and renin-angiotensin-aldosterone systems;^5,6 (2) arterial stiffness;^7,8 (3) cardiac hypertrophy;⁹ and (4) inflammation.¹⁰ With regards to the last, hypertension and target organ damage are linked to increased levels of circulating inflammatory biomarkers,¹¹ which may regulate cell adhesion molecules (CAM).¹² CAM include intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) – which belong to the immunoglobulin superfamily, and the platelet (P-selectin) and endothelial (E-selectin) selectins. Several studies have shown that these are increased in the setting of endothelial dysfunction, vascular remodeling, and hypertension,¹³ suggesting their potential role as not only biomarkers, but also mediators of cardiovascular diseases.¹⁴

Based on the aforementioned considerations, we hypothesized that soluble adhesion molecules are deregulated in this difficult-to-treat group: RHTN. In this study, we investigated a previously unknown relationship between soluble forms of P-selectin (sP-selectin), E-selectin (sE-selectin), ICAM-1 (sICAM-1) and VCAM-1 (sVCAM-1) with RHTN and target organ damage.

Methods

Subjects

This cross-sectional study included 110 subjects diagnosed with true RHTN from the Specialized Outpatient Clinic in RHTN of the University of Campinas (UNICAMP, Campinas, Brazil) and 112 mild-moderate hypertension (HTN) patients from Hypertension Clinic of Valinhos (Valinhos, Brazil). We defined RHTN according to the American Heart Association Statement as (1) BP remaining above the goal level (≥140/90 mmHg) despite concurrent use of 3 or more antihypertensive drugs of different classes; or (2) controlled BP on 4 or more antihypertensive medications. Ideally, one of the agents should be a diuretic, and all agents should be prescribed at optimal doses.¹

The diagnosis of true RHTN was made after a 6-month clinic follow-up for screening and exclusion of secondary causes of hypertension (primary aldosteronism, pheochromocytoma, coarctation of the aorta, Conn’s or Cushing’s syndrome, renal artery stenosis). Pill counting and the Morisky questionnaire were used to exclude lack of BP control due to poor medication adherence, and ambulatory BP monitoring (ABPM) was performed to exclude white coat hypertension. We included patients >35 years old and excluded patients with symptomatic ischemic heart disease, impaired renal function, liver disease and history of stroke, myocardial infarction and peripheral vascular diseases. This study was approved by the Research Ethics Committee of the Faculty of Medical Sciences, University of Campinas (FCM-UNICAMP, Campinas, Brazil) and was performed in accordance with the Declaration of Helsinki. All participants provided written informed consent before being included in the study (approval n. 188.161/2013).

BP Measurement

BP measurements were performed according to the European Society of Hypertension guidelines.¹⁵ Office systolic BP (SBP) and diastolic BP (DBP) were evaluated using a validated digital sphygmomanometer (HEM-907XL, OMRON Healthcare, Bannockburn, IL, USA) with patients in the sitting position after a 10-min rest. Three consecutive measurements with a 3-min interval between them were assessed by a trained health professional. Twenty-four-hour ABPM was carried out using automatic oscillometric monitor (Spacelabs 90207, Spacelabs, Redmond, WA, USA). Patients were instructed to perform normal daily activities and to record activity in a personal diary during the 24-h recording.

Echocardiography

Left ventricular (LV) dimensions were measured using 2-D M-mode echocardiography according to the American Society of Echocardiography (ASE) recommendations.¹⁶ LV mass index (LVMI) was calculated, and patients grouped according to LVMI >95 g/m² (female patients) and >115 g/m² (male patients) for comparison of cardiac hypertrophy. Two blinded independent investigators evaluated the echocardiographic measurements using a cardio-vascular ultrasound machine (Siemens Acuson CV70, Munich, Bavaria, Germany) with a multi-frequency sector transducer (2–4 MHz). The intraobserver and interobserver coefficients of variation were <9.5% for LVMI.

Pulse Wave Velocity (PWV)

PWV is a non-invasive and reproducible method to estimate arterial stiffness. We used the Sphygmocor System (Artcor, Sidney, NSW, Australia) to assess pulse waves transcutaneously using the right common carotid and femoral arteries with patients in the supine position. PWV was calculated as the distance between the supra-sternal notch and the femoral recording site minus the distance from the supra-sternal notch to the carotid recording site, divided by the transit time (distance in meters/∆time in seconds).¹⁷ We used the mean of 2 PWV and defined PWV≥10 m/s as high arterial rigidity for comparison of vascular damage.¹⁸ We performed 3 consecutive readings and took the median, if the difference between the 2 measurements was >0.5 m/s.

Biochemistry

Blood samples were collected at 08.00 hours after overnight fasting with the patients in the seated position. Aldosterone and renin were measured on radioimmunoassay (Immunotech SAS, Marseille, France) and sP-selectin, sE-selectin, sICAM-1 and sVCAM-1 were measured using enzyme-linked immunosorbent assay (R&D Systems, Minneapolis, MN, USA), according to the manufacturer’s instructions.

Statistical Analysis

Continuous variables are expressed as mean±SD or median (IQR), according to Kolmogorov-Smirnov test. Clinical and biochemistry data for RHTN and HTN were compared using Student’s t-test or Mann-Whitney test. Categorical variables are presented as frequencies and percentages and were compared using chi-squared or Fisher’s exact test. Arterial and cardiac damage were categorized using the cut-offs PWV ≥10 m/s and LVMI >95 (for female patients) or >115 g/m² (for male patients) for all RHTN and HTN subjects. Multiple logistic regression analysis was used to evaluate the association of CAM with resistance to antihypertensive treatment, adjusting for potential confounders. Level of significance was set at 0.05.

Results

Table 1 lists the main clinical characteristics of both the HTN and RHTN subjects. RHTN subjects were found to have impaired glycemic and lipid profiles as well as higher aldosterone when compared with HTN subjects (Table 1). Antihypertensive use was also different between the groups. RHTN individuals used more antiplatelet drugs and a greater number of almost all the antihypertensive medication classes than their HTN counterparts. In contrast, the HTN group used more statins, and glucose-lowering drugs were similar between the groups (Table 2).

Table 1. Subject Characteristics

	HTN (n=112)	RHTN (n=110)
Age (years)	66 (59–72)	59 (52–65)*
Female	69 (62)	72 (65)
Black	16 (14)	51 (46)*
BMI (kg/m2)	27 (24–32)	31 (27–36)*
Waist circumference (cm)	93±12	101±15*
Office SBP (mmHg)	139 (130–148)	148 (134–163)*
Office DBP (mmHg)	81 (76–86)	83 (78–92)*
Office PP (mmHg)	57 (50–65)	64 (55–75)*
24-h ABPM SBP (mmHg)	127 (119–135)	130 (118–143)
24-h ABPM DBP (mmHg)	76 (67–81)	75 (70–85)
24-h ABPM PP (mmHg)	51 (46–59)	52 (45–61)
HR (beats/min)	66 (60–73)	66 (58–74)
PWV (m/s)	9.2 (7.5–10.9)	9.1 (7.6–11.5)
LVMI (g/m2)	100 (86–119)	115 (91–139)*
Glucose (mg/dl)	97 (90–107)	100 (88–130)
HbA1C (%)	6.0 (5.7–6.3)	6.2 (5.9–7.5)*
Cholesterol (mg/dl)	165 (142–185)	182 (154–210)*
LDL-C (mg/dl)	86 (67–105)	100 (83–127)*
HDL-C (mg/dl)	49 (40–57)	46 (39–56)
Triglycerides (mg/dl)	111 (81–150)	123 (89–185)
Urea (mg/dl)	34 (29–42)	35 (27–45)
Creatinine (mg/dl)	0.94 (0.80–1.10)	0.93 (0.79–1.17)
Renin (pg/ml)	31 (12–77)	24 (11–65)
Aldosterone (pg/ml)	65 (38–104)	92 (55–175)*
Urinary Na (mEq/24 h)	199±92	205±95
Creatinine clearance (ml/min/1.73 m2)	79 (60–96)	85 (67–100)

Data given as mean±SD, median (IQR) or n (%). *P<0.05. ABPM, ambulatory blood pressure monitoring; BMI, body mass index; DBP, diastolic blood pressure; HbA1C, glycated hemoglobin; HDL-C, high-density lipoprotein cholesterol; HR, heart rate; HTN, mild-moderate hypertension; LDL-C, low-density lipoprotein cholesterol; LVMI, left ventricular mass index; PP, pulse pressure; PWV, pulse wave velocity; RHTN, resistant hypertension; SBP, systolic blood pressure.

Table 2. Medication Use

	HTN (n=112)	RHTN (n=110)
AntiHTN drugs
No. classes	2±1	4±1*
Diuretics	77 (69)	96 (87)*
MRA	02 (02)	40 (36)*
ACEI	18 (16)	41 (37)*
ARB	82 (73)	58 (53)*
CCB	48 (43)	88 (80)*
β-blockers	15 (13)	76 (70)*
Others	01 (01)	31 (28)*
Statins	87 (78)	57 (52)*
Glucose-lowering drugs	42 (38)	53 (48)
Antiplatelet drugs	19 (17)	62 (56)*

Data given as mean±SD or n (%). *P<0.05. ACEI, angiotensin-converting enzyme inhibitors; AntiHTN, antihypertensive; ARB, angiotensin receptor blockers; CCB, calcium channel blockers; MRA, mineralocorticoid receptor antagonists. Other abbreviations as in Table 1.

In addition, both sP-selectin and sE-selectin were increased, while sICAM-1 was reduced in RHTN compared with HTN patients (Figure). Similar sVCAM-1 was seen between the groups.

Figure.

Level of soluble platelet selectin (sP-selectin), soluble endothelial selectin (sE-selectin), soluble intracellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) in mild-moderate hypertension (HTN) vs. resistant HTN (RHTN). *P<0.05.

sP-selectin and sVCAM-1 were elevated in all hypertensive patients with either arterial stiffness (PWV ≥10 m/s) or cardiac hypertrophy (Table 3), but sP-selectin was still associated with target organ damage after adjustment for age and BP. On logistic regression analysis. sP-selectin, sE-selectin and sICAM were independently associated with resistance to antihypertensive therapy. In another model, adjusted for both cardiac and vascular damage, only sE-selectin remained as a significant indicator (Table 4).

Table 3. Adhesion Molecule Level in Target Organ Damage (n=222)

	PWV		LVMI
	<10 m/s	≥10 m/s	<95/115 g/m2	≥95/115 g/m2
sP-selectin	89±45	104±47*,†	88±43	105±51*,‡
sE-selectin	43±17	47±16	44±16	45±17
sICAM-1	302±115	299±117	301±116	300±112
sVCAM-1	1,060±412	1,189±411*,†	1,040±383	1,170±433*,‡

*P<0.05 for ^†PWV ≥10 vs. PWV <10 m/s and ^‡LVMI ≥95/115 vs. LVMI <95/115 g/m². sE-selectin, soluble endothelial selectin; sICAM-1, soluble intracellular adhesion molecule-1; sP-selectin, soluble platelet selectin; sVCAM-1, soluble vascular cell adhesion molecule-1. Other abbreviations as in Table 1.

Table 4. Indicators of RHTN

Median cut-offs	OR (95% CI)	P-value
Model 1†
sP-selectin >89.14 (ng/ml)	2.58 (1.22–5.44)	0.01
sE-selectin >44.28 (ng/ml)	2.08 (1.03–4.20)	0.04
sICAM-1 <291.5 (ng/ml)	2.17 (1.05–4.49)	0.03
sVCAM-1 >1,068 (ng/ml)	1.20 (0.56–2.56)	0.64
Model 2‡
sP-selectin >89.14 (ng/ml)	1.32 (0.56–3.01)	0.53
sE-selectin >44.28 (ng/ml)	2.81 (1.23–6.44)	0.01
sICAM-1 <291.5 (ng/ml)	2.04 (0.88–4.72)	0.10
sVCAM-1 >1,068 (ng/ml)	1.32 (0.54–3.18)	0.54

^†Adjusted for age, gender, race and BMI; ^‡adjusted for age, gender, race, BMI, PWV and LVMI. Abbreviations as in Tables 1,3.

Discussion

Accumulating evidence suggests that RHTN is associated with inflammation¹⁰ and oxidative stress.^19,20 Because these processes are accompanied by infiltration of immune cells into target tissues including the perivascular sites and the kidney, adhesion molecules are likely to be deregulated in RHTN. Inflammatory cells release mediators including cytokines and metalloproteinases that promote cardiovascular remodelling.²¹ We found that sP-selectin and sE-selectin are increased, while sICAM-1 is reduced and sVCAM-1 is similar in RHTN compared with BP-controlled peers. Moreover, apart from potential confounders, sP-selectin was associated with target organ damage and sE-selectin with resistance to antihypertensive therapy.

Adhesion molecules play major roles in the preservation of tissue integrity, mediation of cellular interactions and supply of extracellular matrix contact. Studies have indicated higher levels of adhesion molecules in hypertension.^22,23 As an example, increased circulating levels have been observed in obese subjects and in patients with target organ damage with coexisting hypertension.^24,25 It is therefore not surprising that we observe even greater levels of these in RHTN, given that there is a high prevalence of obesity and cardiovascular remodeling in this condition.¹ The mechanisms leading to increases in these are unclear, and might not be similar for the specific markers.²⁶ In contrast, in vivo and in vitro studies have shown that levels of soluble CAM are elevated in states of increased cell membrane expression in response to endothelial structure and function.²⁷

sE-selectin is produced exclusively by endothelial cells, suggesting that it would provide a circulating surrogate indicator of endothelial activation and damage.²⁸ sE-selectin plays a major role in leukocyte attachment to the endothelium.²⁹ In doing this, the entry of leukocytes into the subendothelial space is increased, promoting oxidative stress and atherosclerosis.³⁰ A previous study has shown that sE-selectin is associated with higher SBP and DBP as well as body mass index (BMI), fasting glucose and C-reactive protein in otherwise healthy subjects,³¹ suggesting that E-selectin might be a useful biomarker for metabolic disorders related to RHTN. This supports the present finding that sE-selectin is associated with resistance to antihypertensive therapy and thus, increased sE-selectin is associated with high cardiovascular risk due to the lack of BP control.³² HTN might not be severely affected by elevated BP, or other risk factors may have to accompany HTN in order to increase E-selectin expression.

sP-selectin – a plasma marker of platelet activation that facilitates the adhesion of platelets to leukocytes and endothelium – is associated with hypertension³³ and adverse cardiovascular prognosis.³⁴ P-selectin was independently associated with arterial stiffness and intima-media thickness.³⁵ The present study identified the role of sP-selectin in cardiac and vascular damage in all hypertensive subjects (RHTN and HTN) after adjustment for age and BP, which are known to contribute to the development and progression of cardiovascular remodeling.^36,37 In this context, inhibition of neointimal formation after arterial injury in an experimental design of P-selectin deficiency,³⁸ and the secretion of thromboxane A2 by activated platelets, may explain the mechanism of involvement of sP-selectin in functional alteration of target organ damage. Moreover, synthesis of P-selectin is increased by some inflammatory mediators. Upregulation of this in endothelial cells has been attributed to tumor necrosis factor (TNF)-α,³⁹ being mediated by nuclear factor-κB transcription factor.⁴⁰ Indeed, we previously demonstrated that RHTN patients have increased TNF-α, as well as target organ damage compared with normotensive subjects,¹⁰ which could explain the present findings and also infer that increased platelet activation is occurring in the RHTN group. The relative contribution of inflammation and endothelial activation in the structural vascular and cardiac changes, however, beyond the BP-mediated effects, in hypertension remains unclear.

ICAM-1 and VCAM-1, identified as endothelial dysfunction biomarkers, play a key role in the early stages of the inflammatory response to facilitate leukocyte adhesion to vascular endothelial cells. Interestingly, soluble ICAM-1 and VCAM-1 did not change after the invasive procedure of renal denervation. It was suggested that the prolonged endothelial remodeling process in atherosclerotic lesions might cause the persistence of increased biomarker concentrations, even apart from sympathetic stimulus.¹⁴ We found that ICAM-1 is reduced in RHTN compared with HTN, probably by the chronic status of resistance to therapy, implying that in essential hypertension there is a very early activation of the endothelial adhesion molecules that favors atherosclerosis.⁴¹ In contrast, no change in sVCAM-1 was found between the present groups. In another study age, but not BP, was the primary determinant of sVCAM-1 level.⁴² Similarly, we found that age was correlated with sVCAM-1 in both the RHTN and HTN patients (r=0.30; P<0.001), which also may explain why the controlled subjects had similarly levels of sVCAM-1 as RHTN, given that the former group was older. Finally supporting this, the noted relationship between sVCAM-1 and target organ damage was no longer significant after age and BP adjustment.

Current antihypertensive approaches exert pleiotropic cardiovascular effects due to their anti-inflammatory properties.⁴³ Angiotensin-converting enzyme inhibitors (ACEI) and mineralocorticoid receptor antagonists, but not angiotensin receptor blockers, have significantly decreased plasma circulating adhesion molecule levels, including that of ICAM-1.^44,45 These findings, in part, may explain the higher ICAM-1, in contrast to the other soluble adhesion molecules, in controlled HTN compared with RHTN, due to the lower prevalence of ACEI and spironolactone use in controlled HTN. Indeed, this may support the change in the expression of soluble molecules between the groups. On multivariate linear regression analysis adjusted for age, race, BMI, gender and resistance to antihypertensive treatment, neither the different classes of antihypertensive drugs, nor statins, glucose-lowering and antiplatelet drugs were independently associated with adhesion molecules. The only 2 exceptions were: (1) diuretics were negatively associated with sE-selectin (β coefficient=–15.6; SE=5.4; P<0.01) and (2) β-blockers were positively associated with sICAM-1 (β coefficient=73.0; SE=31.2; P=0.02). These possible sources of interference, however, did not affect the results, given that RHTN subjects had increased sE-selectin and reduced sICAM-1, despite the greater prevalence of diuretic and β-blockers agents. It is worth noting that the lack of standard therapy in the present RHTN and HTN groups was due to the individualized care. In addition, the antihypertensive and non-antihypertensive drugs could not be withdrawn due to ethical concerns. Therefore, further large clinical studies are required to determine the potential favorable effects of hypertensive treatments to clarify whether these biomarker changes are related to BP reduction or to additional effects.

Some limitations should be mentioned. This was a cross-sectional study therefore causal relationship cannot be inferred. It is not evident whether the adhesion molecules promote the target organ damage and hypertension or whether the high BP causes cardiovascular remodeling which then initiates activation of cell adhesion cascade. The negative finding for sVCAM-1 may be attributed to low power to detect differences between the groups.

The present findings have clarified the effects of adhesion molecules, in particular sP-selectin on arterial stiffness and cardiac hypertrophy, and sE-selectin on resistance to antihypertensive therapy. These findings raise the question of whether early treatment and intensive monitoring of hypertension is crucial reducing the risk for cardiovascular complications and to achieve BP control, although a normotensive group is needed to confirm this hypothesis. Prospective studies are needed to establish the biological functions of soluble forms and their association with cardiovascular risk, and the regulation of the adhesion process itself.

Acknowledgments

This study was supported by the São Paulo Research Foundation (FAPESP), the National Council for Scientific and Technological Development (CNPq); and Coordination for the Improvement of Higher Education Personnel (CAPES), Brazil.

Disclosures

All authors declare no conflict of interest.

References

• 1.    Calhoun  DA,  Jones  D,  Textor  S,  Goff  DC,  Murphy  TP,  Toto  RD, et al. Resistant hypertension: Diagnosis, evaluation, and treatment: A scientific statement from the American Heart Association Professional Education Committee of the Council for High Blood Pressure Research. Hypertension 2008; 51: 1403–1419.
• 2.    Lotufo  PA,  Pereira  AC,  Vasconcellos  PS,  Santos  IS,  Mill  JG,  Bensenor  IM. Resistant hypertension: Risk factors, subclinical atherosclerosis, and comorbidities among adults – the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). J Clin Hypertens (Greenwich) 2015; 17: 74–80.
• 3.    Bhatt  DL,  Kandzari  DE,  O’Neill  WW,  D’Agostino  R,  Flack  JM,  Katzen  BT, et al. A controlled trial of renal denervation for resistant hypertension. N Engl J Med 2014; 370: 1393–1401.
• 4.    Kario  K,  Ogawa  H,  Okumura  K,  Okura  T,  Saito  S,  Ueno  T, et al. SYMPLICITY HTN-Japan: First randomized controlled trial of catheter-based renal denervation in Asian patients. Circ J 2015; 79: 1222–1229.
• 5.    DiBona  GF. Nervous kidney: Interaction between renal sympathetic nerves and the renin-angiotensin system in the control of renal function. Hypertension 2000; 36: 1083–1088.
• 6.    Sowers  JR,  Whaley-Connell  A,  Epstein  M. Narrative review: The emerging clinical implications of the role of aldosterone in the metabolic syndrome and resistant hypertension. Ann Intern Med 2009; 150: 776–783.
• 7.    Sutton-Tyrrell  K,  Newman  A,  Simonsick  EM,  Havlik  R,  Pahor  M,  Lakatta  E, et al. Aortic stiffness is associated with visceral adiposity in older adults enrolled in the study of health, aging, and body composition. Hypertension 2001; 38: 429–433.
• 8.    Tomiyama  H,  Matsumoto  C,  Kimura  K,  Odaira  M,  Shiina  K,  Yamashina  A. Pathophysiological contribution of vascular function to baroreflex regulation in hypertension. Circ J 2014; 78: 1414–1419.
• 9.    Salles  GF,  Fiszman  R,  Cardoso  CR,  Muxfeldt  ES. Relation of left ventricular hypertrophy with systemic inflammation and endothelial damage in resistant hypertension. Hypertension 2007; 50: 723–728.
• 10.    Barbaro  NR,  Fontana  V,  Modolo  R,  De Faria  AP,  Sabbatini  AR,  Fonseca  FH, et al. Increased arterial stiffness in resistant hypertension is associated with inflammatory biomarkers. Blood Press 2015; 24: 7–13.
• 11.    Yamaguchi  K,  Wakatsuki  T,  Soeki  T,  Niki  T,  Taketani  Y,  Oeduka  H, et al. Effects of telmisartan on inflammatory cytokines and coronary plaque component as assessed on integrated backscatter intravascular ultrasound in hypertensive patients. Circ J 2014; 78: 240–247.
• 12.    van Bussel  BC,  Schouten  F,  Henry  RM,  Schalkwijk  CG,  de Boer  MR,  Ferreira  I, et al. Endothelial dysfunction and low-grade inflammation are associated with greater arterial stiffness over a 6-year period. Hypertension 2011; 58: 588–595.
• 13.    Chae  CU,  Lee  RT,  Rifai  N,  Ridker  PM. Blood pressure and inflammation in apparently healthy men. Hypertension 2001; 38: 399–403.
• 14.    Dorr  O,  Liebetrau  C,  Mollmann  H,  Gaede  L,  Troidl  C,  Rixe  J, et al. Soluble fms-like tyrosine kinase-1 and endothelial adhesion molecules (intercellular cell adhesion molecule-1 and vascular cell adhesion molecule-1) as predictive markers for blood pressure reduction after renal sympathetic denervation. Hypertension 2014; 63: 984–990.
• 15.    Mancia  G,  Fagard  R,  Narkiewicz  K,  Redon  J,  Zanchetti  A,  Bohm  M, et al. 2013 ESH/ESC guidelines for the management of arterial hypertension: The Task Force for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC). Eur Heart J 2013; 34: 2159–2219.
• 16.    Sahn  DJ,  DeMaria  A,  Kisslo  J,  Weyman  A. Recommendations regarding quantitation in M-mode echocardiography: Results of a survey of echocardiographic measurements. Circulation 1978; 58: 1072–1083.
• 17.    Laurent  S,  Cockcroft  J,  Van Bortel  L,  Boutouyrie  P,  Giannattasio  C,  Hayoz  D, et al. Expert consensus document on arterial stiffness: Methodological issues and clinical applications. Eur Heart J 2006; 27: 2588–2605.
• 18.    Van Bortel  LM,  Laurent  S,  Boutouyrie  P,  Chowienczyk  P,  Cruickshank  JK,  De Backer  T, et al. Expert consensus document on the measurement of aortic stiffness in daily practice using carotid-femoral pulse wave velocity. J Hypertens 2012; 30: 445–448.
• 19.    Kirabo  A,  Fontana  V,  de Faria  AP,  Loperena  R,  Galindo  CL,  Wu  J, et al. DC isoketal-modified proteins activate T cells and promote hypertension. J Clin Invest 2014; 124: 4642–4656.
• 20.    de Faria  AP,  Fontana  V,  Modolo  R,  Barbaro  NR,  Sabbatini  AR,  Pansani  IF, et al. Plasma 8-isoprostane levels are associated with endothelial dysfunction in resistant hypertension. Clin Chim Acta 2014; 433: 179–183.
• 21.    Savoia  C,  Schiffrin  EL. Inflammation in hypertension. Curr Opin Nephrol Hypertens 2006; 15: 152–158.
• 22.    Buemi  M,  Allegra  A,  Aloisi  C,  Corica  F,  Alonci  A,  Ruello  A, et al. Cold pressor test raises serum concentrations of ICAM-1, VCAM-1, and E-selectin in normotensive and hypertensive patients. Hypertension 1997; 30: 845–847.
• 23.    Diep  QN,  El Mabrouk  M,  Cohn  JS,  Endemann  D,  Amiri  F,  Virdis  A, et al. Structure, endothelial function, cell growth, and inflammation in blood vessels of angiotensin II-infused rats: Role of peroxisome proliferator-activated receptor-gamma. Circulation 2002; 105: 2296–2302.
• 24.    Glowinska  B,  Urban  M,  Peczynska  J,  Florys  B. Soluble adhesion molecules (sICAM-1, sVCAM-1) and selectins (sE selectin, sP selectin, sL selectin) levels in children and adolescents with obesity, hypertension, and diabetes. Metabolism 2005; 54: 1020–1026.
• 25.    Nadar  SK,  Blann  AD,  Kamath  S,  Beevers  DG,  Lip  GY. Platelet indexes in relation to target organ damage in high-risk hypertensive patients: A substudy of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT). J Am Coll Cardiol 2004; 44: 415–422.
• 26.    Jekell  A,  Malmqvist  K,  Wallen  NH,  Mortsell  D,  Kahan  T. Markers of inflammation, endothelial activation, and arterial stiffness in hypertensive heart disease and the effects of treatment: Results from the SILVHIA study. J Cardiovasc Pharmacol 2013; 62: 559–566.
• 27.    Pigott  R,  Dillon  LP,  Hemingway  IH,  Gearing  AJ. Soluble forms of E-selectin, ICAM-1 and VCAM-1 are present in the supernatants of cytokine activated cultured endothelial cells. Biochem Biophys Res Commun 1992; 187: 584–589.
• 28.    Gearing  AJ,  Newman  W. Circulating adhesion molecules in disease. Immunol Today 1993; 14: 506–512.
• 29.    Kakkar  AK,  Lefer  DJ. Leukocyte and endothelial adhesion molecule studies in knockout mice. Curr Opin Pharmacol 2004; 4: 154–158.
• 30.    Moore  KJ,  Tabas  I. Macrophages in the pathogenesis of atherosclerosis. Cell 2011; 145: 341–355.
• 31.    Mochizuki  K,  Inoue  S,  Miyauchi  R,  Misaki  Y,  Shimada  M,  Kasezawa  N, et al. Plasma sE-selectin level is positively correlated with neutrophil count and diastolic blood pressure in Japanese men. J Nutr Sci Vitaminol (Tokyo) 2013; 59: 447–453.
• 32.    Pierdomenico  SD,  Lapenna  D,  Bucci  A,  Di Tommaso  R,  Di Mascio  R,  Manente  BM, et al. Cardiovascular outcome in treated hypertensive patients with responder, masked, false resistant, and true resistant hypertension. Am J Hypertens 2005; 18: 1422–1428.
• 33.    Spencer  CG,  Gurney  D,  Blann  AD,  Beevers  DG,  Lip  GY; Ascot Steering Committee, Anglo-Scandinavian Cardiac Outcomes Trial. Von Willebrand factor, soluble P-selectin, and target organ damage in hypertension: A substudy of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT). Hypertension 2002; 40: 61–66.
• 34.    Ridker  PM,  Buring  JE,  Rifai  N. Soluble P-selectin and the risk of future cardiovascular events. Circulation 2001; 103: 491–495.
• 35.    Koyama  H,  Maeno  T,  Fukumoto  S,  Shoji  T,  Yamane  T,  Yokoyama  H, et al. Platelet P-selectin expression is associated with atherosclerotic wall thickness in carotid artery in humans. Circulation 2003; 108: 524–529.
• 36.    Nurnberger  J,  Keflioglu-Scheiber  A,  Opazo Saez  AM,  Wenzel  RR,  Philipp  T,  Schafers  RF. Augmentation index is associated with cardiovascular risk. J Hypertens 2002; 20: 2407–2414.
• 37.    Kahan  T. The importance of left ventricular hypertrophy in human hypertension. J Hypertens Suppl 1998; 16: S23–S29.
• 38.    Smyth  SS,  Reis  ED,  Zhang  W,  Fallon  JT,  Gordon  RE,  Coller  BS. Beta(3)-integrin-deficient mice but not P-selectin-deficient mice develop intimal hyperplasia after vascular injury: Correlation with leukocyte recruitment to adherent platelets 1 hour after injury. Circulation 2001; 103: 2501–2507.
• 39.    Weller  A,  Isenmann  S,  Vestweber  D. Cloning of the mouse endothelial selectins: Expression of both E- and P-selectin is inducible by tumor necrosis factor alpha. J Biol Chem 1992; 267: 15176–15183.
• 40.    Pan  J,  McEver  RP. Regulation of the human P-selectin promoter by Bcl-3 and specific homodimeric members of the NF-kappa B/Rel family. J Biol Chem 1995; 270: 23077–23083.
• 41.    Cottone  S,  Mule  G,  Nardi  E,  Lorito  MC,  Guarneri  M,  Arsena  R, et al. Microalbuminuria and early endothelial activation in essential hypertension. J Hum Hypertens 2007; 21: 167–172.
• 42.    DeSouza  CA,  Dengel  DR,  Macko  RF,  Cox  K,  Seals  DR. Elevated levels of circulating cell adhesion molecules in uncomplicated essential hypertension. Am J Hypertens 1997; 10: 1335–1341.
• 43.    Marchesi  C,  Paradis  P,  Schiffrin  EL. Role of the renin-angiotensin system in vascular inflammation. Trends Pharmacol Sci 2008; 29: 367–374.
• 44.    Jilma  B,  Li-Saw-Hee  FL,  Wagner  OF,  Beevers  DG,  Lip  GY. Effects of enalapril and losartan on circulating adhesion molecules and monocyte chemotactic protein-1. Clin Sci (Lond) 2002; 103: 131–136.
• 45.    Rocha  R,  Rudolph  AE,  Frierdich  GE,  Nachowiak  DA,  Kekec  BK,  Blomme  EA, et al. Aldosterone induces a vascular inflammatory phenotype in the rat heart. Am J Physiol Heart Circ Physiol 2002; 283: H1802–H1810.