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1.
Physiol Rev ; 100(3): 1119-1147, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32347156

RESUMO

Intercalated cells (ICs) are found in the connecting tubule and the collecting duct. Of the three IC subtypes identified, type B intercalated cells are one of the best characterized and known to mediate Cl- absorption and HCO3- secretion, largely through the anion exchanger pendrin. This exchanger is thought to act in tandem with the Na+-dependent Cl-/HCO3- exchanger, NDCBE, to mediate net NaCl absorption. Pendrin is stimulated by angiotensin II and aldosterone administration via the angiotensin type 1a and the mineralocorticoid receptors, respectively. It is also stimulated in models of metabolic alkalosis, such as with NaHCO3 administration. In some rodent models, pendrin-mediated HCO3- secretion modulates acid-base balance. However, of probably more physiological or clinical significance is the role of these pendrin-positive ICs in blood pressure regulation, which occurs, at least in part, through pendrin-mediated renal Cl- absorption, as well as their effect on the epithelial Na+ channel, ENaC. Aldosterone stimulates ENaC directly through principal cell mineralocorticoid hormone receptor (ligand) binding and also indirectly through its effect on pendrin expression and function. In so doing, pendrin contributes to the aldosterone pressor response. Pendrin may also modulate blood pressure in part through its action in the adrenal medulla, where it modulates the release of catecholamines, or through an indirect effect on vascular contractile force. In addition to its role in Na+ and Cl- balance, pendrin affects the balance of other ions, such as K+ and I-. This review describes how aldosterone and angiotensin II-induced signaling regulate pendrin and the contribution of pendrin-positive ICs in the kidney to distal nephron function and blood pressure.


Assuntos
Rim/citologia , Rim/fisiologia , Transportadores de Sulfato/metabolismo , Equilíbrio Ácido-Base/efeitos dos fármacos , Equilíbrio Ácido-Base/fisiologia , Aldosterona/farmacologia , Angiotensina II/farmacologia , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Humanos
2.
J Biosoc Sci ; 56(1): 50-62, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-36794341

RESUMO

Blood pressure (BP) control is a key intervention to decrease cardiovascular diseases (CVD), the main cause of death in low and middle-income countries (MIC). Scarce data on the determinants of BP control in Latin America are available. Our objective is to explore the role of gender, age, education, and income as social determinants of BP control in Argentina, a MIC with a universal health care system. We evaluated 1184 persons in two hospitals. Blood pressure was measured using automatic oscillometric devices. We selected those patients treated for hypertension. The average BP of less than 140/90 mmHg was considered a controlled BP. We found 638 hypertensive individuals, of whom 477 (75%) were receiving antihypertensive drugs, and of those, 248 (52%) had controlled BP. The prevalence of low education was more frequent in uncontrolled patients (25.3% vs. 16.1%; P < .01). We did not find association between household income, gender, and BP control. Older patients had less BP control (44% of those older than 75 years vs. 60.9% of those younger than 40; test for trend P < .05). Multivariate regression indicates low education (OR 1.71 95% CI [1.05, 2.79]; P = .03) and older age (OR 1.01; 95% IC [1.00, 1.03]) as independent predictors of the lack of BP control. We conclude that rates of BP control are low in Argentina. In a MIC with a universal health care system low education and old age but not household income are independent predictors of the lack of BP control.


Assuntos
Hipertensão , Determinantes Sociais da Saúde , Humanos , Pressão Sanguínea , América Latina/epidemiologia , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Anti-Hipertensivos/uso terapêutico , Anti-Hipertensivos/farmacologia
3.
Curr Cardiol Rep ; 23(12): 177, 2021 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-34657205

RESUMO

PURPOSE OF REVIEW: Isolated diastolic hypertension (IDH) is a frequent hypertension phenotype. We review IDH pathophysiology, risk stratification, and therapeutic decisions. RECENT FINDINGS: Recent guidelines lowering blood pressure cutoff levels have increased IDH prevalence and likely decreased associated cardiovascular risk. Long-term cardiovascular risk and pharmacological intervention in IDH are controversial. Narrow pulse pressure and other physiological and epidemiological characteristics are shared with a systodiastolic hypertension (SDH) subgroup. We propose that IDH be incorporated into a broader category, predominantly diastolic hypertension (PDH), defined by pulse pressure ≤ 45 mmHg and includes IDH and SDH with a narrow pulse pressure. IDH-PDH is associated with cardiovascular risk in the long term, especially in young patients. Standardization of the IDH definition and population may contribute to future research to understand genetics, pathophysiology, and eventually therapy in this important subgroup of hypertensive patients.


Assuntos
Hipertensão , Pressão Sanguínea , Humanos , Hipertensão/tratamento farmacológico , Fenótipo , Prevalência , Fatores de Risco
4.
J Am Soc Nephrol ; 31(3): 483-499, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32054691

RESUMO

BACKGROUND: Aldosterone activates the intercalated cell mineralocorticoid receptor, which is enhanced with hypokalemia. Whether this receptor directly regulates the intercalated cell chloride/bicarbonate exchanger pendrin is unclear, as are potassium's role in this response and the receptor's effect on intercalated and principal cell function in the cortical collecting duct (CCD). METHODS: We measured CCD chloride absorption, transepithelial voltage, epithelial sodium channel activity, and pendrin abundance and subcellular distribution in wild-type and intercalated cell-specific mineralocorticoid receptor knockout mice. To determine if the receptor directly regulates pendrin, as well as the effect of serum aldosterone and potassium on this response, we measured pendrin label intensity and subcellular distribution in wild-type mice, knockout mice, and receptor-positive and receptor-negative intercalated cells from the same knockout mice. RESULTS: Ablation of the intercalated cell mineralocorticoid receptor in CCDs from aldosterone-treated mice reduced chloride absorption and epithelial sodium channel activity, despite principal cell mineralocorticoid receptor expression in the knockout mice. With high circulating aldosterone, intercalated cell mineralocorticoid receptor gene ablation directly reduced pendrin's relative abundance in the apical membrane region and pendrin abundance per cell whether serum potassium was high or low. Intercalated cell mineralocorticoid receptor ablation blunted, but did not eliminate, aldosterone's effect on pendrin total and apical abundance and subcellular distribution. CONCLUSIONS: With high circulating aldosterone, intercalated cell mineralocorticoid receptor ablation reduces chloride absorption in the CCD and indirectly reduces principal cell epithelial sodium channel abundance and function. This receptor directly regulates pendrin's total abundance and its relative abundance in the apical membrane region over a wide range in serum potassium concentration. Aldosterone regulates pendrin through mechanisms both dependent and independent of the IC MR receptor.


Assuntos
Aldosterona/metabolismo , Proteínas de Transporte de Ânions/fisiologia , Túbulos Renais Coletores/metabolismo , Potássio/sangue , Receptores de Mineralocorticoides/metabolismo , Transportadores de Sulfato/genética , Angiotensina II/farmacologia , Animais , Células Cultivadas , Antiportadores de Cloreto-Bicarbonato/metabolismo , Células Epiteliais/metabolismo , Canais Epiteliais de Sódio/metabolismo , Técnicas In Vitro , Transporte de Íons/fisiologia , Túbulos Renais Coletores/citologia , Camundongos , Camundongos Knockout , Sensibilidade e Especificidade , Transdução de Sinais/efeitos dos fármacos , Canais de Sódio/genética
5.
Am J Physiol Renal Physiol ; 316(6): F1218-F1226, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30838873

RESUMO

Afferent arteriole (Af-Art) diameter regulates pressure and flow into the glomerulus, which are the main determinants of the glomerular filtration rate. Thus, Af-Art resistance is crucial for Na+ filtration. Af-Arts play a role as integrative centers, where systemic and local systems interact to determine the final degree of resistance. The tubule of a single nephron contacts an Af-Art of the same nephron at two locations: in the transition of the thick ascending limb to the distal tubule (macula densa) and again in the connecting tubule. These two sites are the anatomic basis of two intrinsic feedback mechanisms: tubule-glomerular feedback and connecting tubule-glomerular feedback. The cross communications between the tubules and Af-Arts integrate tubular Na+ and water processing with the hemodynamic conditions of the kidneys. Tubule-glomerular feedback provides negative feedback that tends to avoid salt loss, and connecting tubule-glomerular feedback provides positive feedback that favors salt excretion by modulating tubule-glomerular feedback (resetting it) and increasing glomerular filtration rate. These feedback mechanisms are also exposed to systemic modulators (hormones and the nervous system); however, they can work in isolated kidneys or nephrons. The exaggerated activation or absence of any of these mechanisms may lead to disequilibrium in salt and water homeostasis, especially in extreme conditions (e.g., high-salt diet/low-salt diet) and may be part of the pathogenesis of some diseases. In this review, we focus on molecular signaling, feedback interactions, and the physiological roles of these two feedback mechanisms.


Assuntos
Canais Epiteliais de Sódio/metabolismo , Taxa de Filtração Glomerular , Glomérulos Renais/irrigação sanguínea , Túbulos Renais/metabolismo , Circulação Renal , Sódio/metabolismo , Equilíbrio Hidroeletrolítico , Animais , Retroalimentação Fisiológica , Hemodinâmica , Humanos , Túbulos Renais/fisiopatologia , Desequilíbrio Hidroeletrolítico/metabolismo , Desequilíbrio Hidroeletrolítico/fisiopatologia
6.
Am J Physiol Renal Physiol ; 316(1): F195-F203, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30403163

RESUMO

The antifibrotic peptide N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is released from thymosin-ß4 (Tß4) by the meprin-α and prolyl oligopeptidase (POP) enzymes and is hydrolyzed by angiotensin-converting enzyme (ACE). Ac-SDKP is present in urine; however, it is not clear whether de novo tubular release occurs or if glomerular filtration is the main source. We hypothesized that Ac-SDKP is released into the lumen of the nephrons and that it exerts an antifibrotic effect. We determined the presence of Tß4, meprin-α, and POP in the kidneys of Sprague-Dawley rats. The stop-flow technique was used to evaluate Ac-SDKP formation in different nephron segments. Finally, we decreased Ac-SDKP formation by inhibiting the POP enzyme and evaluated the long-term effect in renal fibrosis. The Tß4 precursor and the releasing enzymes meprin-α and POP were expressed in the kidneys. POP enzyme activity was almost double that in the renal medulla compared with the renal cortex. With the use of the stop-flow technique, we detected the highest Ac-SDKP concentrations in the distal nephron. The infusion of a POP inhibitor into the kidney decreased the amount of Ac-SDKP in distal nephron segments and in the proximal nephron to a minor extent. An ACE inhibitor increased the Ac-SDKP content in all nephron segments, but the increase was highest in the distal portion. The chronic infusion of a POP inhibitor increased kidney medullary fibrosis, which was prevented by Ac-SDKP. We conclude that Ac-SDKP is released by the nephron and is part of an important antifibrotic system in the kidney.


Assuntos
Nefropatias/metabolismo , Medula Renal/metabolismo , Néfrons/metabolismo , Oligopeptídeos/metabolismo , Animais , Modelos Animais de Doenças , Fibrose , Nefropatias/patologia , Nefropatias/prevenção & controle , Medula Renal/patologia , Masculino , Metaloendopeptidases/metabolismo , Prolil Oligopeptidases , Ratos Sprague-Dawley , Serina Endopeptidases/metabolismo , Transdução de Sinais , Timosina/metabolismo
7.
Curr Hypertens Rep ; 21(1): 8, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-30659366

RESUMO

PURPOSE OF REVIEW: In this review, we summarized the current knowledge of connecting tubule-glomerular feedback (CTGF), a novel mechanism of renal microcirculation regulation that integrates sodium handling in the connecting tubule (CNT) with kidney hemodynamics. RECENT FINDINGS: Connecting tubule-glomerular feedback is a crosstalk communication between the CNT and the afferent arteriole (Af-Art), initiated by sodium chloride through the epithelial sodium channel (ENaC). High sodium in the CNT induces Af-Art vasodilation, increasing glomerular pressure and the glomerular filtration rate and favoring sodium excretion. CTGF antagonized and reset tubuloglomerular feedback and thus increased sodium excretion. CTGF is absent in spontaneous hypertensive rats and is overactivated in Dahl salt-sensitive rats. CTGF is also modulated by angiotensin II and aldosterone. CTGF is a feedback mechanism that integrates sodium handling in the CNT with glomerular hemodynamics. Lack of CTGF could promote hypertension, and CTGF overactivation may favor glomerular damage and proteinuria. More studies are needed to explore the alterations in renal microcirculation and the role of these alterations in the genesis of hypertension and glomerular damage in animals and humans. KEY POINTS: • CTGF is a vasodilator mechanism that regulates afferent arteriole resistance. • CTGF is absent in spontaneous hypertensive rats and overactivated in Dahl salt-sensitive rats. • CTGF in excess may promote glomerular damage and proteinuria, while the absence may participate in sodium retention and hypertension.


Assuntos
Glomérulos Renais/fisiologia , Túbulos Renais/fisiologia , Microcirculação/fisiologia , Circulação Renal/fisiologia , Animais , Retroalimentação , Humanos , Hipertensão/fisiopatologia , Proteinúria/fisiopatologia , Ratos , Sódio/metabolismo
8.
Eur Heart J Suppl ; 21(Suppl D): D8-D10, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31043864

RESUMO

Hypertension is a growing concern worldwide, causing over 10 million deaths each year. The prevalence of high blood pressure (BP) in Argentina is 36.3% and 38% of these are unaware of their disease. Half of the hypertensive patients are on pharmacological treatment and only a quarter of them are controlled. The International Society of Hypertension initiated the May Measurement Month (MMM) as a global campaign to raise awareness on high BP that may also serve as a temporary solution to the lack of global screening programs worldwide. A volunteer cross-sectional survey was carried out in May 2017 across 56 health centres. Blood pressure measurement, definition of hypertension and statistical analysis followed the MMM protocol. For this awareness campaign, the Argentine Society of Hypertension coined the slogan: 'Know and control your blood pressure'. A total of 32 346 individuals aged at least 18 years were screened during MMM17. After imputation, 16 263 (50.4%) were hypertensive. Of the 12 156 receiving antihypertensive medication 5400 (44.4%) still had uncontrolled BP. MMM17, called in our country 'Know and control your blood pressure', was the largest BP screening campaign done in Argentina. Almost 6 out of 10 hypertensive patients were either not on treatment or were not controlled to the BP goal. These results suggest that appropriate screening can help to identify a significant number of people with high BP.

9.
Am J Physiol Renal Physiol ; 314(1): F99-F106, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28978533

RESUMO

Renal blood flow (RBF) provides important information regarding renal physiology and nephropathies. Arterial spin labeling-magnetic resonance imaging (ASL-MRI) is a noninvasive method of measuring blood flow without exogenous contrast media. However, low signal-to-noise ratio and respiratory motion artifacts are challenges for RBF measurements in small animals. Our objective was to evaluate the feasibility and reproducibility of RBF measurements by ASL-MRI using respiratory-gating and navigator correction methods to reduce motion artifacts. ASL-MRI images were obtained from the kidneys of Sprague-Dawley (SD) rats on a 7-Tesla Varian MRI system with a spin-echo imaging sequence. After 4 days, the study was repeated to evaluate its reproducibility. RBF was also measured in animals under unilateral nephrectomy and in renal artery stenosis (RST) to evaluate the sensitivity in high and low RBF models, respectively. RBF was also evaluated in Dahl salt-sensitive (SS) rats and spontaneous hypertensive rats (SHR). In SD rats, the cortical RBFs (cRBF) were 305 ± 59 and 271.8 ± 39 ml·min-1·100 g tissue-1 in the right and left kidneys, respectively. Retest analysis revealed no differences ( P = 0.2). The test-retest reliability coefficient was 92 ± 5%. The cRBFs before and after the nephrectomy were 296.8 ± 30 and 428.2 ± 45 ml·min-1·100 g tissue-1 ( P = 0.02), respectively. The kidneys with RST exhibited a cRBF decrease compared with sham animals (86 ± 17.6 vs. 198 ± 33.7 ml·min-1·100 g tissue-1; P < 0.01). The cRBFs in SD, Dahl-SS, and SHR rats were not different ( P = 0.35). We conclude that ASL-MRI performed with navigator correction and respiratory gating is a feasible and reliable noninvasive method for measuring RBF in rats.


Assuntos
Processamento de Imagem Assistida por Computador , Nefropatias/diagnóstico por imagem , Nefropatias/patologia , Imageamento por Ressonância Magnética , Animais , Meios de Contraste , Rim/irrigação sanguínea , Rim/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Ratos Sprague-Dawley , Artéria Renal/patologia , Circulação Renal/fisiologia , Marcadores de Spin
10.
Am J Physiol Renal Physiol ; 313(6): F1209-F1215, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28835421

RESUMO

Afferent arteriole (Af-Art) resistance is modulated by two intrinsic nephron feedbacks: 1) the vasoconstrictor tubuloglomerular feedback (TGF) mediated by Na+-K+-2Cl- cotransporters (NKCC2) in the macula densa and blocked by furosemide and 2) the vasodilator connecting tubule glomerular feedback (CTGF), mediated by epithelial Na+ channels (ENaC) in the connecting tubule and blocked by benzamil. High salt intake reduces Af-Art vasoconstrictor ability in Dahl salt-sensitive rats (Dahl SS). Previously, we measured CTGF indirectly, by differences between TGF responses with and without CTGF inhibition. We recently developed a new method to measure CTGF more directly by simultaneously inhibiting NKCC2 and the Na+/H+ exchanger (NHE). We hypothesize that in vivo during simultaneous inhibition of NKCC2 and NHE, CTGF causes an Af-Art dilatation revealed by an increase in stop-flow pressure (PSF) in Dahl SS and that is enhanced with a high salt intake. In the presence of furosemide alone, increasing nephron perfusion did not change the PSF in either Dahl salt-resistant rats (Dahl SR) or Dahl SS. When furosemide and an NHE inhibitor, dimethylamiloride, were perfused simultaneously, an increase in tubular flow caused Af-Art dilatation that was demonstrated by an increase in PSF. This increase was greater in Dahl SS [4.5 ± 0.4 (SE) mmHg] than in Dahl SR (2.5 ± 0.3 mmHg; P < 0.01). We confirmed that CTGF causes this vasodilation, since benzamil completely blocked this effect. However, a high salt intake did not augment the Af-Art dilatation. We conclude that during simultaneous inhibition of NKCC2 and NHE in the nephron, CTGF induces Af-Art dilatation and a high salt intake failed to enhance this effect.


Assuntos
Arteríolas/fisiopatologia , Glomérulos Renais/irrigação sanguínea , Túbulos Renais/fisiopatologia , Circulação Renal , Cloreto de Sódio na Dieta/efeitos adversos , Vasodilatação , Amilorida/análogos & derivados , Amilorida/farmacologia , Animais , Arteríolas/efeitos dos fármacos , Arteríolas/metabolismo , Canais Epiteliais de Sódio/efeitos dos fármacos , Canais Epiteliais de Sódio/metabolismo , Retroalimentação Fisiológica , Furosemida/farmacologia , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Masculino , Ratos Endogâmicos Dahl , Circulação Renal/efeitos dos fármacos , Trocadores de Sódio-Hidrogênio/antagonistas & inibidores , Trocadores de Sódio-Hidrogênio/metabolismo , Membro 1 da Família 12 de Carreador de Soluto/antagonistas & inibidores , Membro 1 da Família 12 de Carreador de Soluto/metabolismo , Fatores de Tempo , Resistência Vascular , Vasoconstrição , Vasodilatação/efeitos dos fármacos
11.
Am J Physiol Renal Physiol ; 310(10): F1026-34, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26962108

RESUMO

N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is a natural tetrapeptide with anti-inflammatory and antifibrotic properties. Previously, we have shown that prolyl oligopeptidase (POP) is involved in the Ac-SDKP release from thymosin-ß4 (Tß4). However, POP can only hydrolyze peptides shorter than 30 amino acids, and Tß4 is 43 amino acids long. This indicates that before POP hydrolysis takes place, Tß4 is hydrolyzed by another peptidase that releases NH2-terminal intermediate peptide(s) with fewer than 30 amino acids. Our peptidase database search pointed out meprin-α metalloprotease as a potential candidate. Therefore, we hypothesized that, prior to POP hydrolysis, Tß4 is hydrolyzed by meprin-α. In vitro, we found that the incubation of Tß4 with both meprin-α and POP released Ac-SDKP, whereas no Ac-SDKP was released when Tß4 was incubated with either meprin-α or POP alone. Incubation of Tß4 with rat kidney homogenates significantly released Ac-SDKP, which was blocked by the meprin-α inhibitor actinonin. In addition, kidneys from meprin-α knockout (KO) mice showed significantly lower basal Ac-SDKP amount, compared with wild-type mice. Kidney homogenates from meprin-α KO mice failed to release Ac-SDKP from Tß4. In vivo, we observed that rats treated with the ACE inhibitor captopril increased plasma concentrations of Ac-SDKP, which was inhibited by the coadministration of actinonin (vehicle, 3.1 ± 0.2 nmol/l; captopril, 15.1 ± 0.7 nmol/l; captopril + actinonin, 6.1 ± 0.3 nmol/l; P < 0.005). Similar results were obtained with urinary Ac-SDKP after actinonin treatment. We conclude that release of Ac-SDKP from Tß4 is mediated by successive hydrolysis involving meprin-α and POP.


Assuntos
Rim/metabolismo , Metaloendopeptidases/metabolismo , Oligopeptídeos/metabolismo , Serina Endopeptidases/metabolismo , Timosina/metabolismo , Animais , Pressão Sanguínea , Captopril , Ácidos Hidroxâmicos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Prolil Oligopeptidases , Distribuição Aleatória , Ratos Sprague-Dawley
13.
Am J Hypertens ; 37(2): 127-133, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-37777195

RESUMO

BACKGROUND: Nocturnal hypertension (NH) is a potent cardiovascular risk factor described frequently in people with HIV (PWH). Isolated NH (INH) is less well reported in PWH because of the need for ambulatory blood pressure monitoring (ABPM) in office normotensive patients. We aim to document the prevalence of NH and INH and the clinical factors associated with these phenotypes. METHODS: Cross-sectional study from an HIV program in Argentina. Office and ABPM measurements, as well as clinical and laboratory exploration, were performed. We defined INH as NH with daytime normotension in patients with office normotension. RESULTS: We obtained ABPM in 66 PWH, 60% male, aged 44.7 (IQR 27-69) years; 87% receiving antiretroviral therapy, and 86.2% virologically suppressed. ABPM-based hypertension prevalence was 54.7% (95% CI: 42.5-66.3). The prevalence of NH was 48.5% (32/66), while the INH prevalence was 19.7% (95% CI: 11.7-30.9). No differences were found regarding sex, HIV viral load, CD4+ T lymphocytes count, or years of infection between normotensive and INH patients. Multiple linear regression model adjusted for sex and age determined that body mass index (ß = 0.93, P < 0.01), plasma uric acid (ß = 0.25, P = 0.04), plasma potassium (ß = -10.1, P = 0.01), and high-sensitivity C-reactive protein (hs-CRP) (ß = 0.78, P = 0.02) independently predicted nocturnal systolic blood pressure (BP) in PWH. In a multiple logistic regression model adjusted for age and sex, the presence of sedentariness, plasma potassium <4 mEq/L, BMI, and hs-CRP levels were predictors of INH. CONCLUSION: INH is highly prevalent in PWH. Metabolic and inflammatory markers predict nocturnal SBP in PWH.


Assuntos
Infecções por HIV , Hipertensão , Humanos , Masculino , Feminino , Estudos Transversais , Monitorização Ambulatorial da Pressão Arterial , HIV , Proteína C-Reativa , Ritmo Circadiano , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipertensão/etiologia , Pressão Sanguínea/fisiologia , Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Potássio
14.
bioRxiv ; 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38106229

RESUMO

Background: N-methyl-D-aspartate receptor (NMDAR) are amino acid receptors that are well studied in brain physiology; however, their role in kidney is poorly understood. Nonetheless, NMDAR inhibitors can increase serum K+ and reduce GFR, which suggests they have an important physiological role in the kidney. We hypothesized that NMDARs in the distal nephron induce afferent-arteriole vasodilation through the vasodilator mechanism connecting-tubule-glomerular feedback (CNTGF) that involves ENaC activation. Methods and results: Using a tubule-specific transcriptome database combined with molecular biology and microscopy techniques, we showed kidney expression of NMDAR subunits along the nephron and specifically in ENaC-positive cells. This receptor is expressed in both male and female mice, with higher abundance in females (p=0.02). Microperfusing NMDAR agonists into the connecting tubule induced afferent-arteriole vasodilation (EC50 10.7 vs. 24.5 mM; p<0.001) that was blunted or eliminated with the use of NMDAR blocker MK-801 or with the ENaC inhibitor Benzamil, indicating a dependence on CNTGF of the NMDAR-induced vasodilation. In vivo, we confirmed this CNTGF-associated vasodilation using kidney micropuncture (Stop-flow pressure 37.9±2.6 vs. 28.6±1.9 mmHg, NMDAR agonist vs vehicle; p<0.01). We explored NMDAR and ENaC channel interaction by using mpkCCD cells and split-open connecting tubules. We observed increased amiloride-sensitive current following NMDAR activation that was prevented by MK-801 (1.14 vs. 0.4 µAmp; p=0.03). In split-open tubules, NMDAR activation increased ENaC activity (Npo Vehicle vs. NMDA; p=0.04). Conclusion: NMDARs are expressed along the nephron, including ENaC-positive cells, with higher expression in females. Epithelial NMDAR mediates renal vasodilation through the connecting-tubule-glomerular feedback, by increasing ENaC activity.

15.
J Hypertens ; 41(9): 1446-1455, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37337866

RESUMO

BACKGROUND: Raised blood pressure (BP) remains the biggest risk factor contributing to the global burden of disease and mortality, despite the COVID-19 pandemic. May Measurement Month (MMM), an annual global screening campaign aims to highlight the importance of BP measurement by evaluating global awareness, treatment and control rates among adults with hypertension. In 2021, we assessed the global burden of these rates during the COVID-19 pandemic. METHODS: Screening sites were set up in 54 countries between May and November 2021 and screenees were recruited by convenience sampling. Three sitting BPs were measured, and a questionnaire completed including demographic, lifestyle and clinical data. Hypertension was defined as a systolic BP at least 140 mmHg and/or a diastolic BP at least 90 mmHg (using the mean of the second and third readings) or taking antihypertensive medication. Multiple imputation was used to impute the average BP when readings were missing. RESULTS: Of the 642 057 screenees, 225 882 (35.2%) were classified as hypertensive, of whom 56.8% were aware, and 50.3% were on antihypertensive medication. Of those on treatment, 53.9% had controlled BP (<140/90 mmHg). Awareness, treatment and control rates were lower than those reported in MMM campaigns before the COVID-19 pandemic. Minimal changes were apparent among those testing positive for, or being vaccinated against COVID-19. Of those on antihypertensive medication, 94.7% reported no change in their treatment because of the COVID-19 pandemic. CONCLUSION: The high yield of untreated or inadequately treated hypertension in MMM 2021 confirms the need for systematic BP screening where it does not currently exist.


Assuntos
COVID-19 , Hipertensão , Adulto , Humanos , Pressão Sanguínea , Anti-Hipertensivos/uso terapêutico , Pandemias , COVID-19/diagnóstico , COVID-19/epidemiologia , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia
16.
Cardiovasc Res ; 119(2): 381-409, 2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-36219457

RESUMO

ABSTRACT: Raised blood pressure (BP) is the leading cause of preventable death in the world. Yet, its global prevalence is increasing, and it remains poorly detected, treated, and controlled in both high- and low-resource settings. From the perspective of members of the International Society of Hypertension based in all regions, we reflect on the past, present, and future of hypertension care, highlighting key challenges and opportunities, which are often region-specific. We report that most countries failed to show sufficient improvements in BP control rates over the past three decades, with greater improvements mainly seen in some high-income countries, also reflected in substantial reductions in the burden of cardiovascular disease and deaths. Globally, there are significant inequities and disparities based on resources, sociodemographic environment, and race with subsequent disproportionate hypertension-related outcomes. Additional unique challenges in specific regions include conflict, wars, migration, unemployment, rapid urbanization, extremely limited funding, pollution, COVID-19-related restrictions and inequalities, obesity, and excessive salt and alcohol intake. Immediate action is needed to address suboptimal hypertension care and related disparities on a global scale. We propose a Global Hypertension Care Taskforce including multiple stakeholders and societies to identify and implement actions in reducing inequities, addressing social, commercial, and environmental determinants, and strengthening health systems implement a well-designed customized quality-of-care improvement framework.


Assuntos
COVID-19 , Doenças Cardiovasculares , Hipertensão , Humanos , Pressão Sanguínea , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Renda
17.
Medicina (B Aires) ; 80(5): 453-461, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-33048789

RESUMO

Cardiovascular diseases (CVD) are a growing cause of mortality between human immunodeficiency virus (HIV) infected patients. Hypertension (HTN) and metabolic syndrome (MS) are important causes of CVD. The prevalence of HTN and MS in HIV infected patients in Córdoba, Argentina is unknown. Our aim is to determine the prevalence of HTN and MS in HIV patients in Córdoba and their association with immunological state, inflammation and highly active antiretroviral therapy (HAART) in an observational study. Sixty-five HIV infected patients from the provincial HIV program were randomly selected. Fifty-seven (87%) were on HAART, 39 (60%) were males. The mean age was 44.7 ± 10 years. Mean CD4+ T lymphocytes (CD4+T) count was 404.4 ± 289.6 cells/ml. Viral load (VL) was undetectable in 56 (86.2%). The prevalence of HTN was 40%, and it was associated with the duration of HAART (p < 0.05). There was no association between years of HIV infection, CD4+T, VL and blood pressure. The prevalence of MS was 38.5% (25/65). MS was more frequent between those with HAART (OR: 1.80; CI 95%; 1.43-2.28; p = 0.02). Patients on HAART had higher rates of hypertriglyceridemia, impaired glucose tolerance and lower levels of HDLc (p < 0.01). MS was associated with the HAART duration (p < 0.01). HIV infected patients had a high prevalence of HTN and MS. HAART was associated with both HTN and MS, but there was no association between immunological status, VL or inflammatory markers.


La enfermedad cardiovascular y sus factores de riesgos como hipertensión arterial (HTA) y síndrome metabólico (SM), son una creciente causa de mortalidad entre los infectados con HIV. Nuestros objetivos fueron determinar la prevalencia HTA y SM en pacientes HIV positivos de la ciudad de Córdoba su asociación con el estado inmunológico, inflamación y terapia antirretroviral (TARAA). Fue un estudio aleatorizado de corte transversal. Se incluyeron 65 pacientes HIV positivos del programa provincial HIV-Córdoba, 57 (87%) recibían TARAA, 39 (60%) eran masculinos, con edad promedio de 44.7 ± 10 años. La concentración de linfocitos T CD4+ (LTCD4+) fue 404.4 ± 289.6 cel./ml. La carga viral (CV) fue indetectable en 56 (86.2%). La prevalencia de HTA fue de 40% (26/65) y se asoció a la duración de TARAA (p < 0.05). No hubo asociación entre años de infección por HIV, LTCD4+ y CV con HTA. La prevalencia de SM fue de 38.5% (25/65). El uso de TARAA fue más frecuente en aquellos con SM (OR: 1.80; IC95%: 1.43-2.28; p = 0.02). Pacientes bajo TARAA presentaron alta tasa de hipertrigliceridemia, intolerancia a la glucosa y niveles bajos de HDL (todos p < 0.01). SM se asoció a la duración de TARAA (p < 0.01). La TARAA se asoció a HTA y SM, no encontrándose relación con estado inmunológico, CV o marcadores de inflamación.


Assuntos
Infecções por HIV/epidemiologia , Hipertensão/epidemiologia , Adulto , Terapia Antirretroviral de Alta Atividade , Argentina/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade
18.
Am J Hypertens ; 32(12): 1186-1191, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31350551

RESUMO

BACKGROUND: Hypertension (HTN) is responsible for a significant disease burden in Jamaica. We are reporting the results of the 2017 blood pressure (BP) screening campaign May Measurement Month in Jamaica that aimed to increase the awareness of HTN. METHODS: Adults, 18 years old and older, from different parishes of Jamaica were invited to participate during May to June 2017. Demographic data were collected. BP, weight, and height were measured and recorded. RESULTS: Five hundred sixty-six participants (n = 566) were enrolled, 91.6% (519) from urban areas, and 72.6% (410) were females. The average age was 53.7 (18-95) years old and body mass index was 28.2 ± 6.6 kg/m2. The prevalence of HTN was 47.3% (267/566), without gender or living areas differences (both P > 0.1). Prevalence of HTN was lower in those who self-identified as Interracial ethnicity, in comparison with Afro-Caribbean (33% vs. 48.3%; P = 0.04). About third of the hypertensive patients were not aware of the high BP (89/267; 35.6%). Between hypertensive patients, 64.4% (172/267) were receiving antihypertensive drugs. The rate of BP control was 32% of the hypertensive patients and 50% of those receiving antihypertensive medication. Significant lower BP control was observed between diabetic vs. nondiabetic patients (34.3% vs. 60%; P < 0.001). CONCLUSION: We found a high prevalence of HTN in this population, especially in patients with diabetes or previous cardiovascular diseases. We report an increase in HTN awareness in Jamaica but more advances need to be performed to increase HTN treatment and control.


Assuntos
Determinação da Pressão Arterial , Pressão Sanguínea , Promoção da Saúde , Hipertensão/diagnóstico , Programas de Rastreamento , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/etnologia , Hipertensão/fisiopatologia , Jamaica/epidemiologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Fatores de Risco , Fatores de Tempo , Adulto Jovem
19.
Hypertension ; 71(6): 1133-1142, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29632102

RESUMO

Thymosin ß4 (Tß4), a ubiquitous peptide, regulates several cellular processes that include cell morphology, wound healing, and inflammatory response. Administration of exogenous Tß4 is protective in diabetic nephropathy and in a unilateral ureteral obstruction model. However, the role of endogenous Tß4 in health and disease conditions remains unclear. To elucidate the pathophysiological role of endogenous Tß4 in hypertension, we examined angiotensin-II (Ang-II)-induced renal and cardiac damage in Tß4 knockout (Tß4 KO) mice. Tß4 KO and wild-type C57BL/6 mice were infused continuously for 6 weeks with either vehicle or Ang-II (980 ng/kg per minute). At baseline, Tß4 deficiency did not affect renal and cardiac function. Systolic blood pressure in the Ang-II group was similar in wild-type and Tß4 KO mice (wild-type Ang-II, 179.25±10.11 mm Hg; Tß4 KO Ang-II, 169.81±6.54 mm Hg). Despite the similar systolic blood pressure after Ang-II infusion, Tß4-deficient mice had dramatically increased albuminuria and decreased nephrin expression in the kidney (P<0.005). In the heart of Tß4 KO mice, Ang-II reduced ejection fraction and shortening fraction (ejection fraction: wild-type Ang-II 77.95%±1.03%; Tß4 KO Ang-II 62.58%±3.25%; P<0.005), which was accompanied by cardiac hypertrophy and left ventricular dilatation. In addition, renal and cardiac infiltration of CD68 macrophages, intercellular adhesion molecule-1, and total collagen content were increased after Ang-II infusion in Tß4 KO mice (P<0.005). Overall, our data indicate that endogenous Tß4 is crucial in preventing tissue injury from Ang-II-induced hypertension. This study gives new insights into the protective role of endogenous Tß4 in hypertensive end-organ damage.


Assuntos
Injúria Renal Aguda/fisiopatologia , Pressão Sanguínea/fisiologia , Cardiomiopatias/fisiopatologia , Hipertensão/fisiopatologia , Timosina/administração & dosagem , Timosina/deficiência , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/prevenção & controle , Angiotensina II/toxicidade , Animais , Cardiomiopatias/metabolismo , Cardiomiopatias/prevenção & controle , Hipertensão/induzido quimicamente , Hipertensão/metabolismo , Infusões Intravenosas , Masculino , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos , Distribuição Aleatória , Ratos
20.
Am J Hypertens ; 31(8): 902-909, 2018 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-29722788

RESUMO

BACKGROUND: Obesity is a public health problem, associated with salt sensitive hypertension, kidney inflammation, and fibrosis. N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is a tetra peptide with anti-inflammatory and anti-fibrotic properties. However, its effect on preventing kidney damage in obesity is unknown. We hypothesized that Zucker obese (ZO) rats on a high-salt (HS) diet develop renal damage, inflammation, fibrosis, and this is prevented with Ac-SDKP treatment. METHODS: Zucker lean (ZL) and ZO rats (8 weeks old) were treated with Ac-SDKP (1.6 mg/kg/day) while maintained on either a normal-salt (NS; 0.4%) or HS (4%) diet for 8 weeks. Systolic blood pressure (SBP), albuminuria, renal inflammation, and fibrosis were evaluated. RESULTS: HS diet increased macrophage infiltration in the kidneys of both ZL and ZO rats but was significantly higher in ZO rats receiving the HS diet (ZL + NS, 13.9 ± 1.3 vs. ZL + HS, 19.14 ± 1.5 and ZO + NS, 25.5 ± 1.4 vs. ZO + HS, 87.8 ± 10.8 cells/mm2; P < 0.05). Ac-SDKP prevented macrophage infiltration in ZO rats (ZO + HS + Ac-SDKP, 32.18 ± 2.4 cells/mm2; P < 0.05). Similarly, glomerulosclerosis, cortical, and medullary interstitial fibrosis were increased in ZO rats fed the HS diet, and Ac-SDKP attenuated these alterations (P < 0.05). SBP was increased in ZO rats fed the HS diet (ZO + NS, 121.3 ± 8.9 vs. ZO + HS, 164 ± 6.9 mm Hg; P < 0.05), and it was significantly decreased with Ac-SDKP treatment (ZO + HS + Ac-SDKP, 144.05 ± 14.1 mm Hg; P = 0.004). Albuminuria was higher in ZO rats than in ZL rats; however, neither HS nor Ac-SDKP treatment affected it. CONCLUSIONS: Ac-SDKP treatment in ZO rats fed a HS diet prevented renal damage by reducing inflammation, fibrosis, and SBP.


Assuntos
Anti-Inflamatórios/farmacologia , Anti-Hipertensivos/farmacologia , Glomerulonefrite/prevenção & controle , Hipertensão/prevenção & controle , Rim/efeitos dos fármacos , Obesidade/tratamento farmacológico , Oligopeptídeos/farmacologia , Cloreto de Sódio na Dieta , Albuminúria/etiologia , Albuminúria/fisiopatologia , Albuminúria/prevenção & controle , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Fibrose , Glomerulonefrite/etiologia , Glomerulonefrite/patologia , Glomerulonefrite/fisiopatologia , Hipertensão/etiologia , Hipertensão/fisiopatologia , Rim/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Obesidade/complicações , Obesidade/fisiopatologia , Ratos Zucker
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