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Dendritic cells (DCs) play an important role in T cell alterations in primary hypertension (PH). We determined the numbers and maturation markers of peripheral blood total DCs (tDCs), myeloid cells (mDCs), and plasmacytoid cells (pDCs) and their association with hypertension-mediated organ damage (HMOD) markers and selected immune parameters in 30 adolescents with white coat hypertension (WCH), 25 adolescents with PH and a group of 35 age- and sex-matched children with normotension. Using multicolor flow cytometry, expression of maturation markers (CD86 and CD83) in tDCs (Lin1 - /HLA-DR + ), myeloid DCs (Lin1 - /HLA-DR + /CD11c + ) (mDCs), and plasmacytoid DCs (Lin1 - /HLA-DR + /CD123 + ) (pDCs) and the distribution of peripheral Th17-bearing and T-reg cells were defined. In subjects with hypertension, carotid intima-media thickness (cIMT), left ventricular mass index (LVMI), and pulse wave velocity (PWV) were assessed. Compared with WCH and subjects with normotension, subjects with hypertension had reduced tDC and pDC numbers, an increased percentage of mDC subsets, an elevated mDC/pDC ratio, an increased population of mature mDC and pDC subsets bearing CD83 of high density, a decreased subset of CD86-bearing pDCs, and increased expression of DC activation markers (HLA-DR, CD86), as well as CD11c (mDCs) and CD123 (pDCs). PWV, LVMI, and cIMT values correlated negatively with tDCs and pDCs and positively with mDC numbers. Expression of DC maturation/activation markers (CD83, CD86, HLA-DR, CD11c, and CD123) correlated positively with PWV. Certain DC characteristics of WCH subjects resembled those of PH subjects (decreased tDC frequency and upregulation of activation marker expression). These changes correlated with HMOD. WCH subjects presented a DC phenotype that was intermediate between the normotensive and hypertensive phenotypes., (© 2021. The Author(s), under exclusive licence to The Japanese Society of Hypertension.)

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) play an important role in cardiovascular remodeling. The aim of the study was to analyze MMP/TIMP genes expression in peripheral blood leukocytes of 80 hypertensive children (15.1 ± 2.0 years) in comparison with age-matched 78 normotensive children (14.6 ± 2.0 years; n.s.). TIMP and MMP expression in peripheral blood leukocytes was assessed by quantitative real-time PCR. Hypertensive children independently of age, sex, and body mass index had greater expression of MMP-2 than normotensive controls (p = 0.0001). Patients with left ventricular hypertrophy had greater expression of MMP-14 than patients with normal left ventricular mass (p = 0.006) and TIMP-2 expression correlated with carotid wall cross-sectional area (p = 0.03; r = 0.238). MMP-14 expression correlated with BMI-SDS (p = 0.001; r = 0.371), waist circumference-SDS (p = 0.016; r = 0.290), hsCRP (p = 0.003; r = 0.350), serum HDL-cholesterol (p = 0.008; r = -0.304), and serum uric acid (p = 0.0001; r = 0.394). In conclusion, hypertensive adolescents presented significant alterations of MMP/TIMP expression pattern in comparison with normotensive peers. Moreover, altered MMP/TIMP expression was associated with hypertensive target organ damage and metabolic abnormalities.

Background: Matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) are involved in cardiovascular remodeling in hypertension. Because metabolic abnormalities typical of metabolic syndrome is the dominant phenotype of primary hypertension in children, we hypothesized that MMP-9 and TIMP-1 plasma concentrations are altered in hypertensive children and correlate with metabolic abnormalities and target organ damage., Method: A total of 109 children (15.6, 10-17 years) with untreated primary hypertension were included to the study. The control group consisted of 74 healthy, normotensive children., Results: Plasma MMP-9, TIMP-1 concentrations, and MMP-9/TIMP-1 ratio were significantly elevated in hypertensive boys in comparison with normotensive boys (P = 0.0001, P = 0.04, and P = 0.001, respectively), whereas there were no differences between hypertensive and normotensive girls. The levels of MMP-9 and TIMP-1 as well as MMP-9/TIMP-1 ratio were not associated either with hypertension stage, left ventricular hypertrophy, or carotid intima-media thickness. However, in a subgroup of 30 hypertensive patients in whom arterial stiffness was measured, TIMP-1 concentrations correlated with aortic pulse pressure (P < 0.05; r = 0.367), augmentation pressure (P < 0.05; r = 0.428), and augmentation index (P < 0.05; r = 0.404).Only hypertensive boys presented negative correlations of both MMP-9 and TIMP-1 levels with high-density lipoprotein cholesterol (r = -0.254, P = 0.01 and r = -0.241, P = 0.02, respectively)., Conclusion: Hypertensive boys but not girls had elevated MMP-9 and TIMP-1 plasma concentrations, which indicates sex-related role of MMP/TIMP system in pediatric hypertension. The correlation between serum TIMP-1 and markers of arterial stiffness indicates on the involvement of TIMPs in arterial remodeling.

There is an increasing amount of data indicating that primary hypertension (PH) is not only a hemodynamic phenomenon but also a complex syndrome involving abnormal fat tissue distribution, over-activity of the sympathetic nervous system (SNS), metabolic abnormalities, and activation of the immune system. In children, PH usually presents with a typical phenotype of disturbed body composition, accelerated biological maturity, and subtle immunological and metabolic abnormalities. This stage of the disease is potentially reversible. However, long-lasting over-activity of the SNS and immuno-metabolic alterations usually lead to an irreversible stage of cardiovascular disease. We describe an intermediate phenotype of children with PH, showing that PH is associated with accelerated development, i.e., early premature aging of the immune, metabolic, and vascular systems. The associations and determinants of hypertensive organ damage, the principles of treatment, and the possibility of rejuvenation of the cardiovascular system are discussed.

With the rise in obesity epidemic primary hypertension (PH) is now one of the most common chronic diseases in adolescence. In contrast to hypertensive adults, hypertensive children usually are not exposed to other comorbidities such as diabetes, chronic kidney disease and atherosclerosis. Thus, PH in children and adolescents can be treated as the early stage of development of cardiovascular disease. There is increasing amount of data indicating that PH is not only hemodynamic phenomenon but a complex syndrome involving disturbed activity of sympathetic nervous system, metabolic abnormalities and activation of innate and adaptive immune system. We discuss results of the studies on clinical, metabolic and immunological phenotype of hypertensive children, associations between metabolic and immunological abnormalities with target organ damage and results of antihypertensive treatment.

Renin-angiotensin system, metabolic abnormalities, and immune activity have a role in the pathogenesis of primary hypertension. We assessed the leukocyte mRNA expression of angiotensinogen, angiotensin converting enzyme, renin, angiotensin 2 type 1 receptor, CD14 molecule, adiponectin type 1 receptor, and leptin receptor in hypertensive children before and after nonpharmacological treatment. Leukocyte mRNA expression was measured by means of quantitative real-time reverse transcriptase-polymerase chain reaction in 23 hypertensive children before and after 6 months of nonpharmacological treatment based on dietary advice and physical activities. Twenty-three normotensive children matched for age, sex, and body mass index served as a control group. Before treatment patients had elevated expression of angiotensin converting enzyme and CD14 mRNA, decreased expression of angiotensinogen and angiotensin type 1 receptor mRNA, and unchanged expression of renin, adiponectin, and leptin receptors mRNA as compared with controls. Renin mRNA negatively correlated with 24-hour mean arterial pressure and carotid intima-media thickness. Six months of nonpharmacological treatment caused decrease of blood pressure and normalization of metabolic abnormalities. Renin, adiponectin, and leptin receptors mRNA expression decreased and were lower than in control group. Changes in blood pressure, left ventricular mass, carotid intima-media thickness, body mass index, and waist circumference did not correlate with changes in the expression of renin-angiotensin system genes, CD14, leptin, and adiponectin receptors mRNA. We conclude that leukocytes of hypertensive children displayed alterations in the expression of renin-angiotensin system genes as well as those of CD14. Nonpharmacological treatment resulted in downregulation of genes involved in renin-angiotensin activation and those engaged in leukocyte responses to adipokines.

Low-grade inflammation plays a role in the pathogenesis of primary hypertension (PH) and target organ damage (TOD). We evaluated the profile of inflammatory mediators (CRP, RANTES, MIP-1beta, MIP-1alpha, MCP-1, IL-6, angiogenin, adiponectin) in 30 healthy children (12.7 +/- 3.3 years) and 44 patients with untreated PH (13.7 +/- 2.7 years; n.s). Patients had greater concentrations of CRP, MIP-1beta, and RANTES than controls (all p < 0.05). Children with metabolic syndrome (MS) had greater CRP than children without MS (p = 0.007) and CRP correlated with number of MS criteria, body mass index (BMI), visceral fat, deep subcutaneous fat assessed by magnetic resonance imaging, carotid intima-media thickness (cIMT), left ventricular mass index, and markers of oxidative stress. RANTES correlated with cholesterol, LDL cholesterol, ApoB, and ApoB/ApoA1. Angiogenin correlated with BMI, waist circumference, visceral fat, uric acid, and patients with cIMT>2SD had greater concentration of angiogenin than those with normal cIMT (p = 0.03). Adiponectin was lower in patients with cIMT>2SD than in those with normal cIMT (p = 0.02). No model explaining variability of TOD has been built. Elevated RANTES and MIP-1beta and normal IL-6 and TNF-alpha levels indicate a vascular inflammatory process. Lack of correlation between CRP and chemokines suggests that vascular inflammation in PH precedes the systemic inflammatory changes.