RESUMO
BACKGROUND: Increased nerve activity causes hypertension and kidney disease. Recent studies suggest that renal denervation reduces BP in patients with hypertension. Renal NE release is regulated by prejunctional α2A-adrenoceptors on sympathetic nerves, and α2A-adrenoceptors act as autoreceptors by binding endogenous NE to inhibit its own release. However, the role of α2A-adrenoceptors in the pathogenesis of hypertensive kidney disease is unknown. METHODS: We investigated effects of α2A-adrenoceptor-regulated renal NE release on the development of angiotensin II-dependent hypertension and kidney disease. In uninephrectomized wild-type and α2A-adrenoceptor-knockout mice, we induced hypertensive kidney disease by infusing AngII for 28 days. RESULTS: Urinary NE excretion and BP did not differ between normotensive α2A-adrenoceptor-knockout mice and wild-type mice at baseline. However, NE excretion increased during AngII treatment, with the knockout mice displaying NE levels that were significantly higher than those of wild-type mice. Accordingly, the α2A-adrenoceptor-knockout mice exhibited a systolic BP increase, which was about 40 mm Hg higher than that found in wild-type mice, and more extensive kidney damage. In isolated kidneys, AngII-enhanced renal nerve stimulation induced NE release and pressor responses to a greater extent in kidneys from α2A-adrenoceptor-knockout mice. Activation of specific sodium transporters accompanied the exaggerated hypertensive BP response in α2A-adrenoceptor-deficient kidneys. These effects depend on renal nerves, as demonstrated by reduced severity of AngII-mediated hypertension and improved kidney function observed in α2A-adrenoceptor-knockout mice after renal denervation. CONCLUSIONS: Our findings reveal a protective role of prejunctional inhibitory α2A-adrenoceptors in pathophysiologic conditions with an activated renin-angiotensin system, such as hypertensive kidney disease, and support the concept of sympatholytic therapy as a treatment.
Assuntos
Hipertensão Renal/etiologia , Hipertensão Renal/prevenção & controle , Nefrite/etiologia , Nefrite/prevenção & controle , Receptores Adrenérgicos alfa 2/fisiologia , Sistema Nervoso Simpático/fisiopatologia , Transmissão Sináptica/fisiologia , Angiotensina II , Animais , Modelos Animais de Doenças , Hipertensão Renal/fisiopatologia , Camundongos , Camundongos Knockout , Nefrite/fisiopatologia , SimpatectomiaRESUMO
Macrophage-mediated renal injury promotes the development of diabetic nephropathy. Blockade of chemokine (C-C motif) receptor 2 (CCR2) inhibits kidney macrophage accumulation and early glomerular damage in diabetic animals. This study tested early and late interventions with a CCR2 antagonist (CCR2A) in a model of progressive diabetic glomerulosclerosis and determined whether CCR2A provides added benefit over conventional treatment with an angiotensin-converting enzyme inhibitor (ACEi). Diabetes was induced in hypertensive endothelial nitric oxide synthase (Nos3)-deficient mice by administration of five low-dose streptozotocin (STZ) injections daily. Groups of diabetic Nos3-/- mice received a CCR2A (30 mg·kg-1·day-1 PF-04634817 in chow) as an early intervention (weeks 2-15 after STZ). The late intervention (weeks 8-15 after STZ) involved PF-04634817 alone, ACEi (captopril in water 10 mg·kg-1·day-1) alone, or combined ACEi + CCR2A. Control diabetic and nondiabetic Nos3-/- mice received normal chow and water. Early intervention with a CCR2A inhibited kidney inflammation and glomerulosclerosis, albuminuria, podocyte loss, and renal function impairment but not hypertension in diabetic Nos3-/- mice. Late intervention with a CCR2A also inhibited kidney inflammation, glomerulosclerosis, and renal dysfunction but did not affect albuminuria. ACEi alone suppressed hypertension and albuminuria and partially reduced podocyte loss and glomerulosclerosis but did not affect renal dysfunction. Compared with ACEi alone, the combined late intervention with ACEi + CCR2A provided better protection against kidney damage (inflammation, glomerulosclerosis, and renal function impairment) but not albuminuria. In conclusion, this study demonstrates that combining CCR2A and ACEi provides broader and superior renal protection than ACEi alone in a model of established diabetic glomerulosclerosis with hypertension.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Nefropatias Diabéticas/prevenção & controle , Óxido Nítrico Sintase Tipo III/genética , Receptores CCR2/antagonistas & inibidores , Albuminúria/prevenção & controle , Animais , Compostos Azabicíclicos/uso terapêutico , Captopril/uso terapêutico , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/patologia , Progressão da Doença , Hipertensão Renal/etiologia , Hipertensão Renal/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase Tipo III/deficiência , Podócitos/patologia , Pirimidinas/uso terapêuticoRESUMO
The aim of this study was to investigate the renoprotective effect of bardoxolone methyl (BM), a nuclear factor erythroid 2-related factor 2 (Nrf2) activator with an antioxidant effect, in a salt-sensitive hypertension model induced by aldosterone (Ald) and salt. Tubulointerstitial damage with urinary liver-type fatty acid-binding protein (L-FABP) was evaluated using human L-FABP chromosomal transgenic (L-FABP+/-) male mice. The mice in the Ald group (n=7) received systemic Ald infusions via an osmotic minipump and were given 1% NaCl water for 35 days. Those in the Ald-BM group (n=8) were administered BM intraperitoneally in addition to an injection of Ald and salt. The dose of BM was gradually increased every 7 days up to 10 mg kg-1 per day, which was maintained for 14 days. The administration of BM significantly increased renal expression of the Nrf2 target antioxidant gene. Tubulointerstitial damage was significantly ameliorated in the Ald-BM group compared to the Ald group. The increase in reactive oxygen species (ROS) and upregulation of angiotensinogen expression in the kidneys of the Ald group was significantly prevented in the Ald-BM group. The upregulation of human L-FABP expression induced in the kidneys and increase in urinary L-FABP in the Ald group were significantly suppressed by BM administration. In conclusion, BM ameliorated tubulointerstitial damage in the Ald- and salt-induced hypertension model through suppression of both ROS production and intrarenal renin-angiotensin system activation. Urinary L-FABP may be a useful marker reflecting the therapeutic efficacy of BM.
Assuntos
Proteínas de Ligação a Ácido Graxo/urina , Hipertensão Renal/prevenção & controle , Fator 2 Relacionado a NF-E2/metabolismo , Ácido Oleanólico/análogos & derivados , Substâncias Protetoras/uso terapêutico , Sistema Renina-Angiotensina/efeitos dos fármacos , Aldosterona/efeitos adversos , Angiotensinogênio/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Hipertensão Renal/induzido quimicamente , Hipertensão Renal/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Camundongos , Ácido Oleanólico/farmacologia , Ácido Oleanólico/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Sistema Renina-Angiotensina/fisiologia , Cloreto de Sódio/efeitos adversos , Regulação para Cima/efeitos dos fármacosAssuntos
Humanos , Masculino , Feminino , Antagonistas Adrenérgicos beta/uso terapêutico , Hipertensão Renal/prevenção & controle , Falência Renal Crônica/prevenção & controle , Anti-Hipertensivos/uso terapêutico , Fatores de Risco , Diálise Renal , Progressão da Doença , Relação Dose-Resposta a Droga , Hipertensão Renal/etiologia , Falência Renal Crônica/terapia , Falência Renal Crônica/epidemiologiaRESUMO
Importance: The optimal blood pressure (BP) target remains debated in nondiabetic patients with chronic kidney disease (CKD). Objective: To compare intensive BP control (<130/80 mm Hg) with standard BP control (<140/90 mm Hg) on major renal outcomes in patients with CKD without diabetes. Data Sources: Searches of PubMed, MEDLINE, Embase, and Cochrane Library for publications up to March 24, 2016. Study Selection: Randomized clinical trials that compared an intensive vs a standard BP target in nondiabetic adults with CKD, reporting changes in glomerular filtration rate (GFR), doubling of serum creatinine level, 50% reduction in GFR, end-stage renal disease (ESRD), or all-cause mortality. Data Extraction and Synthesis: Random-effects meta-analyses for pooling effect measures. Meta-regression and subgroup analyses for exploring heterogeneity. Main Outcomes and Measures: Differences in annual rate of change in GFR were expressed as mean differences with 95% CIs. Differences in doubling of serum creatinine or 50% reduction in GFR, ESRD, composite renal outcome, and all-cause mortality were expressed as risk ratios (RRs) with 95% CIs. Results: We identified 9 trials with 8127 patients and a median follow-up of 3.3 years. Compared with standard BP control, intensive BP control did not show a significant difference on the annual rate of change in GFR (mean difference, 0.07; 95% CI, -0.16 to 0.29 mL/min/1.73 m2/y), doubling of serum creatinine level or 50% reduction in GFR (RR, 0.99; 95% CI, 0.76-1.29), ESRD (RR, 0.96; 95% CI, 0.78-1.18), composite renal outcome (RR, 0.99; 95% CI, 0.81-1.21), or all-cause mortality (RR, 0.95; 95% CI, 0.66-1.37). Nonblacks and patients with higher levels of proteinuria showed a trend of lower risk of kidney disease progression with intensive BP control. Conclusions and Relevance: Targeting BP below the current standard did not provide additional benefit for renal outcomes compared with standard treatment during a follow-up of 3.3 years in patients with CKD without diabetes. However, nonblack patients or those with higher levels of proteinuria might benefit from the intensive BP-lowering treatments.
Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Hipertensão Renal/prevenção & controle , Falência Renal Crônica/prevenção & controle , Falência Renal Crônica/terapia , Progressão da Doença , Relação Dose-Resposta a Droga , Feminino , Humanos , Hipertensão Renal/etiologia , Falência Renal Crônica/epidemiologia , Masculino , Diálise Renal , Fatores de RiscoAssuntos
Nefropatias/prevenção & controle , Rim/crescimento & desenvolvimento , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/patologia , Peso ao Nascer , Idade Gestacional , Humanos , Hipertensão Renal/embriologia , Hipertensão Renal/patologia , Hipertensão Renal/prevenção & controle , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Rim/embriologia , Rim/patologia , Nefropatias/embriologia , Nefropatias/patologia , Néfrons/patologia , Vigilância da População/métodos , Cuidado Pré-Natal/métodosRESUMO
Questions remain regarding the potential negative effects of dietary high protein (HP) on kidney health, particularly in the context of obesity in which the risk for renal disease is already increased. To examine whether some of the variability in HP effects on kidney health may be due to source of protein, obese fa/fa Zucker rats were given HP (35% of energy from protein) diets containing either casein, soy protein, or a mixed source of animal and plant proteins for 12 weeks. Control lean and obese rats were given diets containing casein at normal protein (15% of energy from protein) levels. Body weight and blood pressure were measured, and markers of renal structural changes, damage, and function were assessed. Obesity alone resulted in mild renal changes, as evidenced by higher kidney weights, proteinuria, and glomerular volumes. In obese rats, increasing the protein level using the single, but not mixed, protein sources resulted in higher renal fibrosis compared with the lean rats. The mixed-protein HP group also had lower levels of serum monocyte chemoattractant protein-1, even though this diet further increased kidney and glomerular size. Soy and mixed-protein HP diets also resulted in a small number of damaged glomeruli, while soy compared with mixed-protein HP diet delayed the increase in blood pressure over time. Since obesity itself confers added risk of renal disease, an HP diet from mixed-protein sources that enables weight loss but has fewer risks to renal health may be advantageous.
Assuntos
Proteínas Alimentares/efeitos adversos , Rim/patologia , Obesidade/patologia , Insuficiência Renal/etiologia , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Biomarcadores/urina , Caseínas/administração & dosagem , Caseínas/efeitos adversos , Quimiocina CCL2/sangue , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/uso terapêutico , Ingestão de Energia , Fibrose , Hipertensão Renal/etiologia , Hipertensão Renal/fisiopatologia , Hipertensão Renal/prevenção & controle , Rim/metabolismo , Rim/fisiopatologia , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Glomérulos Renais/fisiopatologia , Masculino , Obesidade/metabolismo , Obesidade/fisiopatologia , Obesidade/urina , Tamanho do Órgão , Proteinúria/etiologia , Distribuição Aleatória , Ratos Zucker , Insuficiência Renal/fisiopatologia , Insuficiência Renal/prevenção & controle , Índice de Gravidade de Doença , Proteínas de Soja/administração & dosagem , Proteínas de Soja/efeitos adversos , Proteínas de Soja/uso terapêutico , Aumento de PesoRESUMO
The Renin-Angiotensin-Aldosterone System (RAAS) is profoundly involved in the pathogenesis of renal and cardiovascular organ damage, and has been the preferred therapeutic target for renal protection for over 30 years. Monotherapy with either an Angiotensin Converting Enzime Inhibitor (ACE-I) or an Angiotensin Receptor Blocker (ARB), together with optimal blood pressure control, remains the mainstay treatment for retarding the progression toward end-stage renal disease. Combining ACE-Is and ARBs, or either one with an Aldosterone Receptor Antagonist (ARA), has been shown to provide greater albuminuria reduction, and to possibly improve renal outcome, but at an increased risk of potentially severe side effects. Moreover, combination therapy has failed to provide additional cardiovascular protection, and large prospective trials on hard renal endpoints are lacking. Therefore this treatment should, at present, be limited to selected patients with residual proteinuria and high renal risk. Future studies with novel agents, which directly act on the RAAS at multiple levels or have a more favourable side effect profile, are greatly needed to further explore and define the potential for and the limitations of profound pharmacologic RAAS inhibition.
Assuntos
Quimioterapia Combinada/normas , Insuficiência Renal Crônica/tratamento farmacológico , Sistema Renina-Angiotensina/efeitos dos fármacos , Amidas/farmacologia , Amidas/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Quimioterapia Combinada/métodos , Fumaratos/farmacologia , Fumaratos/uso terapêutico , Humanos , Hipertensão Renal/enfermagem , Hipertensão Renal/prevenção & controle , Estudos Prospectivos , Proteinúria/fisiopatologia , Insuficiência Renal Crônica/complicaçõesAssuntos
Anti-Hipertensivos/administração & dosagem , Pressão Sanguínea , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Hipertensão/complicações , Expectativa de Vida , Fibrilação Atrial/prevenção & controle , Pressão Sanguínea/efeitos dos fármacos , Determinação da Pressão Arterial/normas , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Demência Vascular/prevenção & controle , Quimioterapia Combinada , Insuficiência Cardíaca/prevenção & controle , Humanos , Hipertensão/fisiopatologia , Hipertensão/prevenção & controle , Hipertensão Renal/prevenção & controle , Nefrite/prevenção & controleRESUMO
BACKGROUND: Inhibition of transcription factor nuclear factor-kappa B (NFκB) is beneficial in various models of hypertension and renal disease. We hypothesized first that NFκB inhibition during renal development ameliorates hereditary hypertensive renal disease and next whether this was mediated via suppression of peroxisome proliferator-activated receptor (PPAR)γ coactivator 1α (PGC-1α). METHODS AND RESULTS: Prior to the development of renal injury in fawn-hooded hypertensive (FHH) rats, a model of hypertension, glomerular hyperfiltration, and progressive renal injury, NFkB activity, measured by nuclear protein expression of NFkB subunit p65, was enhanced twofold in 2-day-old male and female FHH kidneys as compared to normotensive Wistar-Kyoto (WKY) rats (P < 0.05). Treating FHH dams with pyrrolidine di thio carbamate (PDTC), an NFκB inhibitor, from 2 weeks before birth to 4 weeks after birth diminished NFkB activity in 2-day-FHH offspring to 2-day-WKY levels (P < 0.01). Perinatal PDTC reduced systolic blood pressure from 20 weeks onwards by on average 25 mm Hg (P < 0.001) and ameliorated proteinuria (P < 0.05) and glomerulosclerosis (P < 0.05). In kidneys of 2-day-, 2-week-, and adult offspring of PDTC-treated FHH dams, PGC-1α was induced on average by 67% (quantitative polymerase chain reaction (qPCR)) suggesting that suppression of this factor by NFkB could be involved in renal damage. Follow-up experiments with perinatal pioglitazone (Pio), a PPARγ agonist, failed to confer persistent antihypertensive or renoprotective effects. CONCLUSIONS: Perinatal inhibition of enhanced active renal NFκB in 2-day FHH had persistent antihypertensive and renoprotective effects. However, this was not the case for PPARγ stimulation. NFkB stimulation is therefore involved in renal damage in the FHH model of proteinuric renal disease by pathways other than via PPARγ.
Assuntos
Anti-Hipertensivos/uso terapêutico , Regulação da Expressão Gênica no Desenvolvimento , Hipertensão Renal/tratamento farmacológico , NF-kappa B/genética , Nefrite/prevenção & controle , RNA/genética , Animais , Animais Recém-Nascidos , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Hipertensão Renal/complicações , Hipertensão Renal/genética , Hipertensão Renal/metabolismo , Hipertensão Renal/fisiopatologia , Hipertensão Renal/prevenção & controle , Masculino , NF-kappa B/antagonistas & inibidores , NF-kappa B/biossíntese , Nefrite/genética , Nefrite/fisiopatologia , Ratos , Ratos Endogâmicos WKY , Circulação RenalRESUMO
Medication compliance among individuals with hypertension symbolizes a growing concern within the medical community. It is said that roughly 50% of hypertensive patients in the United States do not comply with their medication regimen. Uncontrolled hypertension in turn can lead to kidney failure and other complications. Because compliance to medication regimens is complex and difficult to ascertain, solutions to this problem must be multifactorial.
Assuntos
Hipertensão Renal/tratamento farmacológico , Falência Renal Crônica/complicações , Adesão à Medicação , Humanos , Hipertensão Renal/etiologia , Hipertensão Renal/prevenção & controle , Estilo de Vida , Adesão à Medicação/psicologia , Adesão à Medicação/estatística & dados numéricos , MotivaçãoRESUMO
Decreasing sodium intake has been associated with improvements in blood pressure (BP) and proteinuria, two important risk factors for CVD and chronic kidney disease (CKD) progression. We aimed to investigate the role of sodium intake by examining the effect of changes in sodium intake over 1 year on BP and proteinuria in people with early stage CKD. From thirty-two general practices, 1607 patients with previous estimated glomerular filtration rate of 59-30 ml/min per 1.73 m² and mean age of 72.9 (sd 9.0) years were recruited. Clinical assessment, urine and serum biochemistry testing were performed at baseline and after 1 year. Sodium intake was estimated from early morning urine specimens using an equation validated for this study population. We found that compared with people who increased their sodium intake from ≤ 100 to >100 mmol/d over 1 year, people who decreased their intake from >100 to ≤ 100 mmol/d evidenced a greater decrease in all BP variables (Δmean arterial pressure (ΔMAP) = -7.44 (SD 10.1) v. -0.23 (SD 10.4) mmHg; P<0.001) as well as in pulse wave velocity (ΔPWV = -0.47 (SD 1.3) v. 0.08 (SD 1.88) m/s; P<0.05). Albuminuria improved only in albuminuric patients who decreased their sodium intake. BP improved in people who maintained low sodium intake at both times and in those with persistent high intake, but the number of anti-hypertensive increased only in the higher sodium intake group, and PWV improved only in participants with lower sodium intake. Decreasing sodium intake was an independent determinant of ΔMAP. Although more evidence is needed, our results support the benefits of reducing and maintaining sodium intake below 100 mmol/d (2.3-2.4 g/d) in people with early stages of CKD.
Assuntos
Dieta Hipossódica , Hipertensão Renal/prevenção & controle , Cooperação do Paciente , Insuficiência Renal Crônica/dietoterapia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Terapia Combinada , Progressão da Doença , Inglaterra/epidemiologia , Feminino , Seguimentos , Humanos , Hipertensão Renal/epidemiologia , Hipertensão Renal/etiologia , Perda de Seguimento , Masculino , Pessoa de Meia-Idade , Pacientes Desistentes do Tratamento , Atenção Primária à Saúde , Estudos Prospectivos , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/urina , Fatores de Risco , Índice de Gravidade de Doença , Sódio/urinaRESUMO
We investigated the involvement of cyclooxygenase-2 (COX-2) and the renin-angiotensin system in N(G)-nitro-L-arginine methyl ester (L-NAME)-induced hypertension. Male Wistar rats were treated with L-NAME (75.0 mg·(kg body mass)(-1)·day(-1), in their drinking water) for different durations (1-33 days). COX-2 and renin mRNA were measured using real-time PCR in the renal cortex, and prostanoids were assessed in the renal perfusate, whereas angiotensin II (Ang II) and Ang (1-7) were quantified in plasma. In some rats, nitric oxide synthase inhibition was carried out in conjunction with oral administration of captopril (30.0 mg·kg(-1)·day(-1)) or celecoxib (1.0 mg·kg(-1)·day(-1)) for 2 or 19 days. We found a parallel increase in renocortical COX-2 and renin mRNA starting at day 2 of treatment with L-NAME, and both peaked at 19-25 days. In addition, L-NAME increased renal 6-Keto-PGF(1α) (prostacyclin (PGI2) metabolite) and plasma Ang II from day 2, but reduced plasma Ang (1-7) at day 19. Captopril prevented the increase in blood pressure, which was associated with lower plasma Ang II and increased COX-2-derived 6-Keto-PGF(1α) at day 2 and plasma Ang (1-7) at day 19. Celecoxib partially prevented the increase in blood pressure; this effect was associated with a reduction in plasma Ang II. These findings indicate that renal COX-2 expression increased in parallel with renin expression, renal PGI2 synthesis, and plasma Ang II in L-NAME-induced hypertension.
Assuntos
Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hipertensão Renal/metabolismo , Córtex Renal/metabolismo , Renina/metabolismo , 6-Cetoprostaglandina F1 alfa/sangue , 6-Cetoprostaglandina F1 alfa/metabolismo , Angiotensina I/sangue , Angiotensina I/metabolismo , Angiotensina II/sangue , Angiotensina II/metabolismo , Animais , Anti-Hipertensivos/uso terapêutico , Captopril/uso terapêutico , Celecoxib/uso terapêutico , Ciclo-Oxigenase 2/química , Ciclo-Oxigenase 2/genética , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Hipertensão Renal/sangue , Hipertensão Renal/prevenção & controle , Córtex Renal/efeitos dos fármacos , Córtex Renal/enzimologia , Masculino , NG-Nitroarginina Metil Éster , Óxido Nítrico/metabolismo , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/metabolismo , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos Wistar , Renina/genéticaRESUMO
OBJECTIVES: The aim of study was to determine the renal effects of glucose transporter 4 (GLUT4) in a hypertensive nephropathy rat model. BACKGROUND: GLUT4 has been implicated in insulin resistance and hypertension in several animal models; however its role in hypertensive nephropathy still remains unclear. METHODS: Hypertensive nephropathy was induced by Nω-nitro-L-arginine (L-NNA), a nitric oxide (NO) synthase inhibitor, 100 mg/ml in drinking water and high salt (HS) diet (4 % NaCl), for 15 days in the presence of insulin, a GLUT 4 agonist (1 U/day) and indinavir, a GLUT4 inhibitor (80 mg/kg/day). RESULTS: Decreased basal renal medullary and cortical blood flow was enhanced in LNNA/HS/indinavir group (p < 0.01) but attenuated (p < 0.05) by insulin. Proteinuria was increased (p < 0.01) in LNNA/HS/indinavir group but attenuated (p < 0.01) by insulin. Insulin-treated rats decreased urine NO (p < 0.01) and urine Na2+ (p < 0.01) compared to other treated animals. In indinavir-treated animals, urine Na2+ was increased by benzamil, an epithelial sodium channel (ENaC) inhibitor (p < 0.01) and hydrochlorothiazide, a sodium/chloride co-transporter (NCC) inhibitor (p < 0.05). CONCLUSION: GLUT4 exerts a renoprotective role which may be related to increase NO production. The antinatriuretic effects of GLUT4 appear to be due to enhancement of ion transport activity of ENaC and NCC at the renal tubules (Fig. 9, Ref. 34).
Assuntos
Transportador de Glucose Tipo 4/metabolismo , Hipertensão Renal/metabolismo , Hipertensão Renal/prevenção & controle , Rim/efeitos dos fármacos , Nefrite/metabolismo , Nefrite/prevenção & controle , Óxido Nítrico/biossíntese , Animais , Arginina/análogos & derivados , Transportador de Glucose Tipo 4/antagonistas & inibidores , Hipertensão Renal/induzido quimicamente , Insulina/metabolismo , Insulina/farmacologia , Rim/irrigação sanguínea , Masculino , Nefrite/induzido quimicamente , Compostos Nitrosos , Ratos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Cloreto de Sódio na DietaRESUMO
Severe renal artery stenosis may cause renovascular hypertension; in case of bilateral narrowing or in a stenotic solitary or transplant kidney, renal insufficiency (ischemic renal disease) or rarely pulmonary flash edema may occur. In most cases arteriosclerotic disease is the underlying cause; less prevalent are the various manifestations of fibromuscular disease. Renal artery stenosis may be treated by revasularization, using either percutaneous (balloon angioplasty, stenting) or rarely open surgical procedures, both with excellent primary patency rates. However, randomized trials of renal artery angioplasty or stenting in patients with arteriosclerotic lesions have failed to demonstrate a longer-term benefit with regard to hypertension control and renal dysfunction over medical management alone. Careful patient selection is essential to maximize the potential benefit (e.g., in patients with refractory hypertension, progressive renal failure or recurrent pulmonary flash edema).
Assuntos
Hipertensão Renal/etiologia , Hipertensão Renal/prevenção & controle , Isquemia/cirurgia , Rim/irrigação sanguínea , Obstrução da Artéria Renal/complicações , Obstrução da Artéria Renal/cirurgia , Humanos , Hipertensão Renal/diagnóstico , Isquemia/complicações , Isquemia/diagnóstico , Obstrução da Artéria Renal/diagnóstico , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/métodosRESUMO
The aim of this study was to observe the effects of uric acid lowering therapy (UALT), febuxostat and allopurinol, on blood pressure (BP) and serum creatinine level. Post-hoc data were derived from a phase-III, randomised, double-blind, 4-week trial of male gouty patients that compared the safety and efficacy of febuxostat and allopurinol in adults with gout. The subjects were randomly assigned to one of five groups, 35-37 in each group (febuxostat: 40, 80, 120 mg/d; allopurinol: 300 mg/d; control group: placebo). Blood pressure and serum creatinine level were measured at baseline and at weeks 2 and 4. Diastolic BP and creatinine level had decreased significantly in the UALT groups compared to the control group at week 4. Diastolic BP had decreased significantly in the allopurinol group and serum creatinine level had decreased significantly in the febuxostat groups at week 4. After adjusting for confounding variables, serum uric acid changes were found to be significantly correlated with changes in serum creatinine level but were not associated with changes in systolic or diastolic BP. UALT in gouty subjects significantly decreased diastolic BP and serum creatinine level. Changes in uric acid were significantly correlated with those in serum creatinine level, suggesting the feasibility of renal function improvement through UALT in gouty men.
Assuntos
Alopurinol/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Creatinina/sangue , Gota/tratamento farmacológico , Hipertensão Renal/prevenção & controle , Tiazóis/administração & dosagem , Biomarcadores/sangue , Relação Dose-Resposta a Droga , Febuxostat , Supressores da Gota/administração & dosagem , Humanos , Hipertensão Renal/diagnóstico , Hipertensão Renal/etiologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do TratamentoRESUMO
BACKGROUND: Nitric oxide (NO) deficiency occurs in humans and animals with hypertension and chronic kidney disease (CKD). An inhibitor of NO synthase, N(G)-nitro-l-arginine methyl ester (L-NAME) exacerbates kidney damage in the adult spontaneously hypertensive rat (SHR). We examined whether L-NAME exacerbated hypertensive nephrosclerosis in young SHRs and whether melatonin protects SHRs against kidney damage by restoration of the asymmetric dimethylarginine (ADMA)-NO pathway. METHODS: Rats aged 4 weeks were randomly assigned into three groups (n = 10 for each group): Group 1 (control), SHRs without treatment; Group 2 (L-NAME), SHRs received L-NAME (80 mg/L) in drinking water; and Group 3 (L-NAME + melatonin), SHRs received L-NAME (80 mg/L) and 0.01% melatonin in drinking water. All rats were sacrificed at 10 weeks of age. RESULTS: L-NAME exacerbates the elevation of blood pressure, renal dysfunction, and glomerular sclerosis in young SHRs. L-NAME induced an increase of ADMA and a decrease of arginine-to-ADMA ratio in the SHR kidney. Melatonin therapy prevented L-NAME-exacerbated hypertension and nephrosclerosis in young SHRs. In addition, melatonin restored L-NAME-induced reduction of dimethylarginine dimethylaminohydrolase (DDAH; ADMA-metabolizing enzymes) activity in the SHR kidney. Next, melatonin decreased renal ADMA concentrations, increased renal arginine-to-ADMA ratio, and restored NO production in L-NAME-treated young SHRs. Moreover, melatonin reduced the degree of oxidative damaged DNA product, 8-hydroxydeoxyguanosine immunostaining in L-NAME-treated SHR kidney. CONCLUSION: Our results indicated that L-NAME/SHR is a useful model for hypertensive nephrosclerosis in young rats. The blood pressure-lowering and renoprotective effects of melatonin is due to increases of DDAH activity, decreases of ADMA, and reduction of oxidative stress in L-NAME-treated SHR kidney. Specific therapy targeting the DDAH-ADMA pathway may be a promising approach to slowing chronic kidney disease progression in children.
Assuntos
Antioxidantes/farmacologia , Hipertensão Renal/prevenção & controle , Rim/enzimologia , Melatonina/farmacologia , Nefrite/prevenção & controle , 8-Hidroxi-2'-Desoxiguanosina , Amidoidrolases/metabolismo , Animais , Arginina/análogos & derivados , Arginina/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Desoxiguanosina/análogos & derivados , Humanos , Hipertensão/metabolismo , Hipertensão/prevenção & controle , Hipertensão Renal/metabolismo , Masculino , NG-Nitroarginina Metil Éster/toxicidade , Nefrite/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Endogâmicos SHRRESUMO
Severe renal artery stenosis may cause renovascular hypertension; in case of bilateral narrowing or in a stenotic solitary kidney, renal insufficiency (ischemic kidney disease) or rarely pulmonary flush edema may occur. Renal artery stenosis may be treated by revascularization, using either percutaneous (balloon angioplasty, stenting) or less common open surgical procedures, both with excellent primary patency rates. However, randomized trials of renal artery angioplasty or stenting have failed to demonstrate a longer-term benefit with regard to blood pressure control and renal function over medical management alone (except for fibromuscular disease). Furthermore, endovascular procedures are associated with substantial risks. It has not yet been demonstrated that renal revascularization leads to a prolongation of event-free survival. Careful patient selection is essential to maximize the potential benefit.
Assuntos
Angioplastia/métodos , Hipertensão Renal/diagnóstico , Hipertensão Renal/prevenção & controle , Obstrução da Artéria Renal/diagnóstico , Obstrução da Artéria Renal/cirurgia , Ensaios Clínicos como Assunto , Medicina Baseada em Evidências , Humanos , Hipertensão Renal/etiologia , Obstrução da Artéria Renal/complicações , Resultado do TratamentoRESUMO
PURPOSE: To retrospectively evaluate and compare the long term patency and antihypertensive effect of angioplasty and stent insertion in renal artery stenosis caused by Takayasu arteritis, with CT angiography and clinical follow-up. MATERIALS AND METHODS: We retrospectively analyzed and compared effects on hypertension and patency of renal artery in 16 patients (age ranging from 16 to 58 years, mean: 32.1 years) with renovascular hypertension caused by Takayasu arteritis who underwent endovascular treatment including angioplasty (n=13) and stent placement (n=9) for 22 stenotic renal arteries. RESULTS: Technical success was 95% (21/22) without major complications. In the last follow-up CT angiogram (mean 85 ± 41 months), restenosis was 8% (1/12) in angioplasty and 66% (6/9) in stent. Patency rates of angioplasty were 100%, 91.7%, 91.7% and primary unassisted and primary assisted patency rates of stent placement were 55.6%, 33.3%, 33.3% and 88.9%, 66.7%, 55.6% at 1-, 3- and 5-years, respectively. In clinical follow-up (mean 120 ± 37.8 months, range 48-183 months), beneficial effects on hypertension were obtained in 87% of patients (13/15) and there was no significant difference between the patients who were treated by only angioplasty and the patients who received stent placement in at least one renal artery, regardless of whether or not angioplasty had been performed in the other renal artery. CONCLUSION: Compared with stent placement, angioplasty demonstrated better long term patency and similar clinical benefit on renovascular hypertension in renal artery stenosis of Takayasu arteritis. We suggest that stent placement should be reserved for obvious angioplasty failure.
Assuntos
Angioplastia , Hipertensão Renal/prevenção & controle , Obstrução da Artéria Renal/complicações , Obstrução da Artéria Renal/cirurgia , Stents , Arterite de Takayasu/complicações , Arterite de Takayasu/cirurgia , Adolescente , Adulto , Angiografia/métodos , Prótese Vascular , Feminino , Seguimentos , Humanos , Hipertensão Renal/diagnóstico , Hipertensão Renal/etiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obstrução da Artéria Renal/diagnóstico por imagem , Estudos Retrospectivos , Arterite de Takayasu/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Significant renal artery stenosis (RAS) may lead to left ventricle (LV) hypertrophy and diastolic function (DF) impairment through complex mechanisms: activation of cytokines and/or systolic and diastolic blood pressure (SBP, DBP) increase. AIM: To assess interrelations between LV mass (LVM), DF and cytokines in patients undergoing renal artery stenting (PTA, percutaneous angioplasty of renal artery). METHODS: The study group comprised 72 subjects (44.4% men), 64.1 ± 9.9 years with RAS referred to PTA. SBP, DBP, transforming growth factor beta1 (TGF-ß1), aldosterone, B-type natriuretic peptide (BNP) levels and change in LVM and LVM index (LVMI) and DF (E(vel), e'(vel), E/A ratio, E/e' ratio, Ar(time)-A(time)) on echocardiography were assessed preprocedurally, and three and 12 months postprocedurally. RESULTS: TGF-ß1 level decreased from 13.3 ± 14.9 to 8.6 ± 8.0 ng/mL (p = 0.027), while BNP increased from 89.1 ± 86.3 to 131 ± 105 pmol/mL (p < 0.001). A significant reduction in LVMI in women (79.4 ± 16.9 vs. 95.7 ± 18.5 g/m², p < 0.001) and men (77.2 ± 16.8 vs. 100.1 ± 19.7 g/m², p < 0.001) was found at 12 months vs. baseline. Degree of LVM reduction correlated with baseline LVM (p < 0.001; r = -0.612) and e'(vel) (p = 0.05; r = 0.230), but not with BP values. Among DF parameters, only e'(vel) increased significantly at 12 months (5.54 ± 1.57 vs. 5.92 ± 1.65 cm/s; p = 0.039), while A/E and E/e' ratio, Ar(time)-A(time) remained similar (p = 0.457, p = 0.283 and p = 0.258). Factors associated with e'(vel) increase ≥ 0.3 cm/s at 12 months were baseline LVM < 165 g (p = 0.043, RR = 1.39, CI 1.01-1.46), E(vel) (p = 0.015, RR = 1.26, CI 1.15-1.52), e'(vel) (p < 0.001, RR = 1.42, CI 1.18-1.7), DBP decrease > 10 mm Hg (p = 0.055, RR = 1.2, CI 1.0-1.44) and TGF-ß1 > 8 ng/mL (p = 0.024, RR = 1.24, CI 1.03-1.49) at 12 months. CONCLUSIONS: Significant LVMI reduction was observed after PTA of RAS, but it was independent of BP reduction. e'(vel) increase was independently associated with baseline LVM, E(vel), e'(vel), and 12 month decrease in DBP > 10 mm Hg.