RESUMO
BACKGROUND: Matrix metalloproteinases (MMPs) are enzymes involved in cardiovascular (CV) remodeling and hypertension-mediated target organ damage (TOD). Genetic polymorphisms in matrix metalloproteinase 2 (MMP-2) gene [-1575G/A (rs243866); -1306C/T (rs243865); and -735C/T (rs2285053)] are associated with several CV conditions, however the relationship between MMP-2 polymorphisms and resistant hypertension (RH) is unknown. We evaluated whether these genetic single nucleotide polymorphisms (SNPs) in MMP-2 gene are associated with 1) MMP-2 and tissue inhibitor of metalloproteinase-2 (TIMP-2) levels in RH and mild to moderate hypertensive (HT) subjects, 2) left ventricular hypertrophy (LVH) and arterial stiffness and 3) the presence of RH. METHODS: One hundred and nineteen RH and 136 HT subjects were included in this cross-sectional study. Genotypes were determined by real-time PCR using TaqMan probes. Haplotypes were estimated using Bayesian method. RESULTS: The levels of MMP-2 and TIMP-2 were similar among genotypes and haplotypes for the three studied polymorphisms in HT and RH groups. RH showed higher frequency for GCC haplotype and lower frequency of GCT and ATC haplotypes (-1575G/A, -1306C/T and -735C/T, respectively) compared to HT (0.77 vs. 0.64; 0.09 vs. 0.17; 0.13 vs. 0.19, p=0.003 respectively). GCC haplotype was associated to RH apart from potential confounders (odds ratio (OR)=2.09; 95% confidence interval (CI)=1.20-3.64; p=0.01). In addition, CC genotype (OR=2.93; 95% CI=1.22-7.01; p=0.02) and C allele (OR=2.81; 95% CI=1.26-6.31; p=0.01) for -735C/T polymorphism were independently associated with RH. GCT haplotype was associated with reduced probability of having RH (OR=0.35; 95% CI=0.16-0.79; p=0.01). Finally, no relationship was found between studied MMP-2 SNPs and left ventricular hypertrophy and arterial stiffness in both groups. CONCLUSION: GCC haplotype carriers showed higher probability to have RH (odds ratio>1), while the GCT haplotype carriers showed lower probability to have RH, suggesting that the GCT haplotype may represent a protective genetic factor for the development of RH. These finds suggest that GCC and GCT haplotypes, and C allele and CC genotype of the -735C/T MMP-2 gene polymorphism may have a role in RH.
Assuntos
Hipertensão/genética , Metaloproteinase 2 da Matriz/genética , Polimorfismo de Nucleotídeo Único , Idoso , Brasil , Estudos de Casos e Controles , Feminino , Haplótipos , Humanos , Hipertensão/patologia , Masculino , Pessoa de Meia-Idade , Pacientes AmbulatoriaisRESUMO
Resistant hypertension (RH) is associated with organ damage and cardiovascular risk. Evidence suggests the involvement of matrix metalloproteinase 2 (MMP-2) and tissue inhibitor of metalloproteinase 2 (TIMP-2) in hypertension and in cardiovascular remodeling. The aim of this study was to assess the levels of MMP-2 and TIMP-2 in RH and its relation with organ damage, including arterial stiffness and cardiac hypertrophy. MMP-2 and TIMP-2 levels were compared among 19 patients with normotension (NT), 116 with nonresistant hypertension (HTN) and 116 patients with resistant HTN (RH). MMP-2 levels showed no differences among NT, HTN, and RH groups, while TIMP-2 levels were higher in RH compared with HTN and NT groups (90.0 [76.1-107.3] vs 70.1 [57.7-88.3] vs 54.7 [40.9-58.1] ng/mL, P<.01), respectively. MMP-2/TIMP-2 ratio was reduced in the RH group compared with the HTN and NT groups (2.7 [1.9-3.4] vs 3.3 [2.6-4.2] vs 4.9 [4.5-5.3], P<.01), respectively. No associations were found between MMP-2 levels, TIMP-2, and MMP-2/TIMP-2 ratio with cardiac hypertrophy and arterial stiffness in the RH and HTN groups. Finally, in a regression analysis, reduced MMP-2/TIMP-2 ratio and increased TIMP-2 levels were independently associated with RH. The present findings provide evidence that TIMP-2 is associated with RH and might be a possible biomarker for screening RH patients.
Assuntos
Hipertensão/sangue , Hipertensão/enzimologia , Metaloproteinase 2 da Matriz/sangue , Inibidor Tecidual de Metaloproteinase-2/sangue , Idoso , Estudos Transversais , Feminino , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Regulação para Cima , Rigidez Vascular , Remodelação VentricularRESUMO
Resistant hypertension (RHTN) is a multifactorial and polygenic disease, frequently associated with obesity. Low plasma adiponectin levels, a hormone produced by the adipose tissue, were associated with RHTN. Single nucleotide polymorphisms (SNPs) -11377C/G (rs266729) and +276G/T (rs1501299) in ADIPOQ (adiponectin gene) were associated with hypertension. This study evaluated the association between two SNPs (-11377C/G and +276G/T) and adiponectin levels in RHTN. This study comprised 109 patients with RHTN genotyped for both polymorphisms. A cross-sectional study was designed to compare features of CC homozygous versus G allele carriers for -11377C/G and GG homozygous versus T allele carriers for +276G/T. Office and ambulatory BP measurements were similar among genotypes subgroups in both SNPs as well as the markers of target organ damage (arterial stiffness, left ventricular mass index and microalbuminuria). Adiponectin concentrations were significantly higher in CC compared to G carrier for -11377C/G (CC:7.0 (4.0-10.2) versus G allele:5.5 (2.5-7.9), p = 0.04) and lower in GG compared to T carrier for +276G/T (GG:5.3 (2.3-7.7) versus T allele:7.1 (3.6-10.5), p = 0.04). Adjusting for systolic ambulatory BP, body mass index, age, gender, race and presence of type 2 diabetes, multiple linear regression analyses revealed that the minor alleles G (ß-coefficient= -0.14, SE=0.07, p = 0.03) and T (ß-coefficient=0.12, SE=0.06, p = 0.04) were independent predictors of adiponectin. The -11377C/G and +276G/T SNPs in ADIPOQ were associated with adiponectin levels in RHTN individuals.
Assuntos
Adiponectina/sangue , Adiponectina/genética , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/genética , Resistência a Medicamentos , Hipertensão/tratamento farmacológico , Hipertensão/genética , Polimorfismo de Nucleotídeo Único , Idoso , Biomarcadores/sangue , Estudos Transversais , Feminino , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Hipertensão/sangue , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Fatores de RiscoRESUMO
PURPOSE: Left ventricular hypertrophy and diastolic dysfunction (LVDD) remain highly frequent markers of cardiac damage and risk of progression to symptomatic heart failure, especially in resistant hypertension (RHTN). We have previously demonstrated that administration of sildenafil in hypertensive rats improves LVDD, restoring phosphodiesterase type 5 (PDE-5) inhibition in cardiac myocytes. METHODS: We hypothesized that the long-acting PDE-5 inhibitor tadalafil may be clinically useful in improving LVDD in RHTN independently of blood pressure (BP) reduction. A single blinded, placebo-controlled, crossover study enrolled 19 patients with both RHTN and LVDD. Firstly, subjects received tadalafil (20 mg) for 14 days and after a 2-week washout period, they received placebo orally for 14 days. Patients were evaluated by office BP and ambulatory BP monitoring (ABPM), endothelial function (FMD), echocardiography, plasma brain natriuretic peptide (BNP-32), cyclic guanosine monophosphate (cGMP) and nitrite levels. RESULTS: No significant differences were detected in BP measurements. Remarkably, at least four echocardiographic parameters related with diastolic function improved accompanied by decrease in BNP-32 in tadalafil use. Although increasing cGMP, tadalafil did not change endothelial function or nitrites. There were no changes in those parameters after placebo. CONCLUSION: The current findings suggest that tadalafil improves LV relaxation through direct effects PDE-5-mediated in the cardiomyocytes with potential benefit as an adjunct to treat symptomatic subjects with LVDD such as RHTN patients.
Assuntos
Carbolinas/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Inibidores da Fosfodiesterase 5/uso terapêutico , Disfunção Ventricular Esquerda/tratamento farmacológico , Idoso , Pressão Sanguínea/efeitos dos fármacos , Carbolinas/farmacologia , Estudos Cross-Over , GMP Cíclico/sangue , Diástole/efeitos dos fármacos , Resistência a Medicamentos , Feminino , Humanos , Hipertensão/sangue , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/sangue , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Nitritos/sangue , Inibidores da Fosfodiesterase 5/farmacologia , Método Simples-Cego , Tadalafila , Disfunção Ventricular Esquerda/sangue , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda/efeitos dos fármacosRESUMO
Obesity, arterial stiffness and high aldosterone levels can interact to cause resistant hypertension (RHTN). Lower adiponectin (APN) levels may be significantly associated with hypertension. However, the importance of hypoadiponectinemia as a complicating factor in the lack of blood pressure (BP) control in individuals with RHTN has not been demonstrated. Ninety-six RHTN patients were classified into uncontrolled (UCRHTN, n = 44) and controlled (CRHTN, n = 52) subgroups. Their APN and aldosterone levels, office and ambulatory BP (ABPM) measurements, endothelium-dependent brachial artery responses (flow-mediated dilation (FMD)), left ventricular mass index (LVMI) and pulse wave velocity (PWV) were evaluated. The UCRHTN subgroup had increased aldosterone levels, as well as higher LVMI and PWV. In addition, lower APN levels and impaired FMD response were found in this subgroup. The brachial and ABPM pulse pressures were inversely associated with the APN levels (r = -0.45, P = 0.002; r = -0.33, P = 0.03, respectively), as were the aldosterone levels and the PWV (r = -0.38, P = 0.01; r = -0.36, P = 0.02, respectively) in UCRHTN patients. The PWV was only significantly influenced by the APN level in the UCRHTN subgroup in the multivariate regression analysis. None of the correlations mentioned above were observed in the CRHTN subgroup. Hypoadiponectinemia and high aldosterone levels may therefore be implicated in resistance to antihypertensive therapy related to arterial stiffness.