RESUMO
OBJECTIVE: We investigated sex differences in blood pressure (BP) response to transcutaneous electrical nerve stimulation (TENS) during orthostatic stress (ORT). METHODS: Seventeen healthy young adults (males = 9; females = 8) underwent TENS or SHAM stimulus applied in the cervicothoracic region for 30 min in the supine position followed by 10 min in the orthostatic position. Electrocardiogram and BP were continuously recorded at rest and during ORT. Stroke volume (SV), cardiac output (CO) and total peripheral resistance (TPR) were calculated from the BP signal. RESULTS: Orthostatic challenge decreased BP similarly for both sexes during ORT, a deeper drop in CO and a slight increase in heart rate were found in women compared with men ( P = 0.03 and 0.05, respectively). TENS evoked a pronounced fall in SBP in men compared with the SHAM condition ( P < 0.05). TENS has no effect on SBP in women compared with the SHAM condition. CONCLUSION: This finding suggests a possible modulatory effect by one cervicothoracic TENS session on sympathetic tonus in healthy men.
Assuntos
Estimulação Elétrica Nervosa Transcutânea , Pressão Sanguínea/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Caracteres Sexuais , Resistência Vascular , Adulto JovemRESUMO
The present study was performed in order to investigate the safety and efficacy of different vasoactive drugs combined with enteral nutrition in terms of treating elderly patients with sepsis. A total of 75 elderly patients with sepsis treated with enteral nutrition in our hospital were randomly divided into three groups: group A (n = 25), group B (n = 25) and group C (n = 25). The three groups were treated with dopamine, dobutamine and norepinephrine respectively. One week after treatment, the therapeutic effects of the three groups were compared, the vascular elastic indexes, hemodynamic indexes and levels of inflammatory factors of the three groups were measured. After treatment, the clinical effective rate of group C was evidently higher than that of group A and group B. The vascular elasticity coefficient and stiffness coefficient in group C were significantly lower than those in group A and group B, and the arterial compliance in group C was significantly higher than that in group A and group B (P < 0.05). The levels of MAP and PVRI in group C were significantly higher than those in group A and B, and the levels of CI, CVP and HR in group C were significantly lower than those in group A and group B (P < 0.05). Norepinephrine elicited greater effects in terms of improving hemodynamic indexes, vascular elasticity and reducing the level of inflammatory factors compared with dopamine and dobutamine in elderly patients harboring sepsis.
Assuntos
Dobutamina/uso terapêutico , Dopamina/uso terapêutico , Nutrição Enteral/métodos , Norepinefrina/uso terapêutico , Choque Séptico/terapia , Simpatomiméticos/uso terapêutico , Idoso , Pressão Arterial , Débito Cardíaco , Pressão Venosa Central , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Sepse/fisiopatologia , Sepse/terapia , Choque Séptico/fisiopatologia , Resultado do Tratamento , Resistência Vascular , Rigidez VascularRESUMO
Arterial hypercapnia reduces renal perfusion. Beetroot juice (BRJ) increases nitric oxide bioavailability and may improve renal blood flow. We tested the hypothesis that acute consumption of BRJ attenuates both decreases in blood velocity and increases in vascular resistance in the renal and segmental arteries during acute hypercapnia. In fourteen healthy young adults, blood velocity and vascular resistance were measured with Doppler ultrasound in the renal and segmental arteries during five minutes of breathing a carbon dioxide gas mixture (CO2) before and three hours after consuming 500 mL of BRJ. There was no difference between pre- and post-BRJ consumption in the increase in the partial pressure of end-tidal CO2 during CO2 breathing (pre: +4 ± 1 mmHg; post: +4 ± 2 mmHg, p = 0.4281). Segmental artery blood velocity decreased during CO2 breathing in both pre- (by -1.8 ± 1.9 cm/s, p = 0.0193) and post-BRJ (by -2.1 ± 1.9 cm/s, p = 0.0079), but there were no differences between pre- and post-consumption (p = 0.7633). Segmental artery vascular resistance increased from room air baseline during CO2 at pre-BRJ consumption (by 0.4 ± 0.4 mmHg/cm/s, p = 0.0153) but not post-BRJ (p = 0.1336), with no differences between pre- and post-consumption (p = 0.7407). These findings indicate that BRJ consumption does not attenuate reductions in renal perfusion during acute mild hypercapnia in healthy young adults.
Assuntos
Beta vulgaris , Sucos de Frutas e Vegetais , Hemodinâmica/efeitos dos fármacos , Hipercapnia/fisiopatologia , Rim/irrigação sanguínea , Raízes de Plantas , Adulto , Pressão Arterial , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Dióxido de Carbono , Ingestão de Líquidos/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Artéria Renal/fisiopatologia , Respiração/efeitos dos fármacos , Volume de Ventilação Pulmonar/efeitos dos fármacos , Ultrassonografia Doppler , Resistência Vascular/efeitos dos fármacosRESUMO
Hypertensive-induced renal damage (HRD) is an important public health and socioeconomic problem worldwide. The herb pair Radix Astragali- (RA-) Radix Salviae Miltiorrhizae (RS) is a common prescribed herbal formula for the treatment of HRD. However, the underlying mechanisms are unclear. The purpose of our study is to explore the mechanism of combination of Radix Astragali (RA) and Radix Salviae Miltiorrhizae (RS) ameliorating HRD by regulation of the renal sympathetic nerve. Thirty 24-week-old spontaneously hypertensive rats (SHRs) as the experimental group were randomly divided into the RA group, the RS group, the RA+RS group, the valsartan group, and the SHR group and six age-matched Wistar Kyoto rats (WKY) as the control group. After 4 weeks of corresponding drug administration, venipuncture was done to collect blood and prepare serum for analysis. A color Doppler ultrasound diagnostic instrument was used to observe renal hemodynamics. Enzyme-linked immunosorbent assay was used to detect norepinephrine (NE), epinephrine (E), angiotensin II (Ang II), and B-type brain natriuretic peptide (BNP). Simultaneously, the kidneys were removed immediately and observed under a transmission electron microscope to observe the ultrastructural changes. And the concentration of transforming growth factor-ß1 (TGF-ß1), angiotensin type 1 receptor (AT1), and nitric oxide (NO) was detected by immunohistochemistry. Our results showed that renal ultrasonography of rats showed no significant difference in renal size among groups. The RA+RS group had obviously decreased vascular resistance index. The levels of NE, E, BNP, Ang II, AT1, and TGF-ß1 were decreased (P < 0.05), and the density of NO was increased. Pathological damage of the kidney was alleviated. In conclusion, the results of the present study suggested sympathetic overexpression in the pathogenesis of HRD. The combination of RA and RS may inhibit the hyperexcitability of sympathetic nerves and maintain the normal physiological structure and function of kidney tissue and has a protective effect on the cardiovascular system.
Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Hipertensão/tratamento farmacológico , Rim/patologia , Salvia miltiorrhiza/química , Animais , Astragalus propinquus , Biomarcadores/sangue , Medicamentos de Ervas Chinesas/farmacologia , Hemodinâmica/efeitos dos fármacos , Hipertensão/sangue , Hipertensão/fisiopatologia , Rim/diagnóstico por imagem , Rim/fisiopatologia , Rim/ultraestrutura , Masculino , Modelos Biológicos , Óxido Nítrico/metabolismo , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptor Tipo 1 de Angiotensina/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Resistência Vascular/efeitos dos fármacosRESUMO
BACKGROUND: Obstruction of coronary microcirculation can lead to myocardial ischemia and poor prognosis. Salvianolate exerts cardiovascular protection at cellular levels. However, no studies have confirmed the effect of salvianolate on stable coronary heart disease (CHD) with high fractional flow reserve (FFR) and myocardial microcirculatory disturbances. METHODS/DESIGN: This study will enroll 78 patients who have stable coronary disease with 50 to 70% stenosis in major coronary arteries and whose FFR > 0.80 and index of microcirculatory resistance (IMR) > 25. Patients will be randomly divided into the salvianolate group or the placebo group. After above evaluations, salvianolate 200 mg will be intravenously dripped immediately for the next 30 min and subsequent 7 days in the salvianolate group, and matching 0.9% normal saline will be arranged in the placebo group. IMR will be reevaluated in immediate phase after first 30 min of salvianolate or placebo treatment. The primary end point will be the IMR change in this phase, and the secondary end points will be the total ischemic burden assessed by the Seattle angina scale, quality of life scale, Holter electrocardiography, and 6-min walk test after 7 days before discharge. DISCUSSION: This study will firstly clarify the improvement effect of salvianolate on coronary microcirculation and provide an effective treatment method for stable CHD patients with high FFR and myocardial microcirculatory disturbance. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1800018772 . Registered on 9 October 2018 and updated on 2 March 2020.
Assuntos
Doença das Coronárias , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Intervenção Coronária Percutânea , Angiografia Coronária , Doença das Coronárias/diagnóstico , Doença das Coronárias/tratamento farmacológico , Vasos Coronários , Humanos , Microcirculação , Extratos Vegetais , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Resistência VascularRESUMO
The aim of this study was to investigate the possible beneficial effects of exercise training (ET) with omega-3/Calanus oil supplementation on cardiorespiratory and adiposity parameters in elderly women. Fifty-five women (BMI: 19-37 kg/m2, 62-80 years old) were recruited and randomly assigned to the 4 month intervention with ET and omega-3 supplementation (Calanus oil, ET-Calanus) or ET and the placebo (sunflower oil; ET-Placebo). The body composition was determined by dual-energy X-ray absorptiometry (DXA), and cardiorespiratory parameters were measured using spiroergometry and PhysioFlow hemodynamic testing. Both interventions resulted in an increased lean mass whereas the fat mass was reduced in the leg and trunk as well as the android and gynoid regions. The content of trunk fat (in percent of the total fat) was lower and the content of the leg fat was higher in the ET-Calanus group compared with the ET-Placebo. Although both interventions resulted in similar improvements in cardiorespiratory fitness (VO2max), it was explained by an increased peripheral oxygen extraction (a-vO2diff) alone in the ET-Placebo group whereas increased values of both a-vO2diff and maximal cardiac output (COmax) were observed in the ET-Calanus group. Changes in COmax were associated with changes in systemic vascular resistance, circulating free fatty acids, and the omega-3 index. In conclusion, Calanus oil supplementation during a 4 month ET intervention in elderly women improved the cardiorespiratory function, which was due to combined central and peripheral cardiodynamic mechanisms.
Assuntos
Envelhecimento/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Suplementos Nutricionais , Exercício Físico/fisiologia , Ácidos Graxos Ômega-3/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Composição Corporal , Débito Cardíaco , Feminino , Humanos , Pessoa de Meia-Idade , Plâncton/química , Resistência VascularRESUMO
BACKGROUND: Finnish sauna bathing habits are associated with a decreased risk of cardiovascular mortality. The physiologic adaptations mediating this association remain to be fully elucidated. This study tested the hypothesis that Finnish sauna bathing acutely improves peripheral flow-mediated dilation (FMD) in middle-aged and older adults with stable coronary artery disease (CAD). METHODS: Twenty-two adults (20 male, 2 female; 67 ± 10 years) with stable CAD underwent 2 periods of 10 minutes in a Finnish sauna (81.3 ± 2.7°C, 23 ± 3% humidity) separated by 10 minutes of thermoneutral rest. Before and 51 ± 8 minutes after sauna bathing, brachial artery FMD and postocclusive reactive hyperemia (PORH) were evaluated by means of Doppler ultrasound. RESULTS: Sauna bathing increased core temperature (mean +0.66°C [95% CI 0.54-0.77], P < 0.01) and heart rate (+27 beats/min [24-29], P < 0.01), and decreased systolic (-19 mm Hg [-31 to -6]; P < 0.01) and diastolic (-6 mm Hg [-11 to -1], P < 0.01) blood pressures. Brachial artery FMD was greater after sauna bathing (+1.21% [0.16-2.26], P = 0.04), whereas PORH was unchanged (peak: +0.51 mL/min/mm Hg [-0.13 to 1.15], P = 0.11; area under the curve: +0.21 mL/mm Hg [-0.12 to 0.54]; P = 0.19). CONCLUSIONS: A typical Finnish sauna bathing session acutely improves peripheral FMD in middle-aged and older adults with stable CAD.
Assuntos
Artéria Braquial/fisiopatologia , Doença da Artéria Coronariana/fisiopatologia , Frequência Cardíaca/fisiologia , Banho a Vapor , Resistência Vascular/fisiologia , Idoso , Artéria Braquial/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia DopplerRESUMO
Supplementation with anthocyanin-rich blackcurrant increases blood flow, cardiac output, and stroke volume at rest. It is not known whether cardiovascular responses can be replicated over longer timeframes in fed trained cyclists. In a randomized, double-blind, crossover design, 13 male trained cyclists (age 39 ± 10 years, VËO2max 55.3 ± 6.7 ml·kg-1·min-1) consumed two doses of New Zealand blackcurrant (NZBC) extract (300 and 600 mg/day for 1 week). Cardiovascular parameters were measured during rest and submaximal cycling (65% VËO2max) on day 1 (D1), D4, and D7. Data were analyzed with an RM ANOVA using dose (placebo vs. 300 vs. 600 mg/day) by time point (D1, D4, and D7). Outcomes from placebo were averaged to determine the coefficient of variation within our experimental model, and 95% confidence interval (CI) was examined for differences between placebo and NZBC. There were no differences in cardiovascular responses at rest between conditions and between days. During submaximal exercise, no positive changes were observed on D1 and D4 after consuming NZBC extract. On D7, intake of 600 mg increased stroke volume (3.08 ml, 95% CI [-2.08, 8.26]; d = 0.16, p = .21), cardiac output (0.39 L/min, 95% CI [-1.39, .60]; d = 0.14, p = .40) (both +2.5%), and lowered total peripheral resistance by 6.5% (-0.46 mmHg·min/ml, 95% CI [-1.80, .89]; d = 0.18, p = .46). However, these changes were trivial and fell within the coefficient of variation of our study design. Therefore, we can conclude that NZBC extract was not effective in enhancing cardiovascular function during rest and submaximal exercise in endurance-trained fed cyclists.
Assuntos
Ciclismo/fisiologia , Suplementos Nutricionais , Hemodinâmica/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Ribes , Adulto , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Consumo de Oxigênio/efeitos dos fármacos , Descanso , Volume Sistólico/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacosRESUMO
BACKGROUND & AIMS: In advanced chronic liver disease (ACLD), deregulated hepatic necroinflammatory processes play a key role in the development of liver microvascular dysfunction, fibrogenesis, and increased hepatic vascular tone, resulting in progression of ACLD and portal hypertension. Given the current lack of an effective treatment, we aimed to characterise the effects of the pan-peroxisome proliferator-activated receptor (pan-PPAR) agonist lanifibranor in 2 preclinical models of ACLD, as well as in liver cells from patients with ACLD. METHODS: Cirrhotic rats (thioacetamide or common bile duct ligation; TAA or cBDL) randomly received lanifibranor (100 mg/kg/day, po) or vehicle for 14 days (n = 12/group). PPAR expression, systemic and hepatic haemodynamics, presence of ascites, liver sinusoidal endothelial cell (LSEC) phenotype, hepatic stellate cell (HSC) activation, serum transaminases and albumin, hepatic macrophage infiltration, cytokine expression, and liver fibrosis were determined. Hepatic cells were isolated from the livers of patients with cirrhosis and their phenotype was evaluated after treatment with either lanifibranor or vehicle. RESULTS: TAA-cirrhotic rats receiving lanifibranor showed significantly lower portal pressure compared with vehicle-treated animals (-15%; p = 0.003) without decreasing portal blood flow, indicating improved hepatic vascular resistance. Moreover, lanifibranor-treated TAA-rats showed decreased ascites, improved LSEC and HSC phenotypes, ameliorated hepatic microvascular function, reduced hepatic inflammation, and significant fibrosis regression (-32%; p = 0.020). These findings were confirmed in the cBDL rat model as well as in human liver cells from patients with cirrhosis, which exhibited phenotypic improvement upon treatment with lanifibranor. CONCLUSIONS: Lanifibranor ameliorates fibrosis and portal hypertension in preclinical models of decompensated cirrhosis. Promising results in human hepatic cells further support its clinical evaluation for the treatment of ACLD. LAY SUMMARY: Advanced chronic liver disease (ACLD) constitutes a serious public health issue for which safe and effective treatments are lacking. This study shows that lanifibranor improves portal hypertension and liver fibrosis, 2 key elements of the pathophysiology of ACLD, in preclinical models of the disease. Evaluation of lanifibranor in liver cells from patients with ACLD further supports its beneficial effects.
Assuntos
Benzotiazóis/farmacologia , Hipertensão Portal , Cirrose Hepática , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Sulfonamidas/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Antifibróticos/farmacologia , Anti-Hipertensivos/farmacologia , Células Cultivadas , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Humanos , Hipertensão Portal/tratamento farmacológico , Hipertensão Portal/etiologia , Hipertensão Portal/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Pressão na Veia Porta/efeitos dos fármacos , Ratos , Resistência Vascular/efeitos dos fármacosRESUMO
BACKGROUND: In cirrhosis, the nitric oxide-soluble guanylyl cyclase (sGC)-cyclic guanosine monophosphate (cGMP) pathway is impaired, which contributes to increased intrahepatic vascular resistance (IHVR) and fibrogenesis. We investigated if sGC stimulation (riociguat (RIO)), sGC activation (cinaciguat (CINA)) or phosphodiesterase (PDE)-5 inhibition (tadalafil (TADA)) improves portal hypertension (PHT) and liver fibrosis. METHODS: Fifty male Sprague-Dawley rats underwent bile-duct ligation (BDL) or sham operation. RIO (0.5 mg/kg), CINA (1 mg/kg), TADA (1.5 mg/kg) or vehicle (VEH) was administered from weeks 2 to 4 after BDL. At week 4, invasive haemodynamic measurements were performed, and liver fibrosis was assessed by histology (chromotrope-aniline blue (CAB), Picro-Sirius red (PSR)) and hepatic hydroxyproline content. RESULTS: Cirrhotic bile duct-ligated rats presented with PHT (13.1 ± 1.0 mmHg) and increased IHVR (4.9 ± 0.5 mmHgâ min/mL). Both RIO (10.0 ± 0.7 mmHg, p = 0.021) and TADA (10.3 ± 0.9 mmHg, p = 0.050) decreased portal pressure by reducing IHVR (RIO: -41%, p = 0.005; TADA: -21%, p = 0.199) while not impacting heart rate, mean arterial pressure and portosystemic shunting. Hepatic cGMP levels increased upon RIO (+239%, p = 0.006) and TADA (+32%, p = 0.073) therapy. In contrast, CINA dosed at 1 mg/kg caused weight loss, arterial hypotension and hyperlactataemia in bile duct-ligated rats. Liver fibrosis area was significantly decreased by RIO (CAB: -48%, p = 0.011; PSR: -27%, p = 0.121) and TADA (CAB: -21%, p = 0.342; PSR: -52%, p = 0.013) compared to VEH-treated bile duct-ligated rats. Hepatic hydroxyproline content was reduced by RIO (from 503 ± 20 to 350 ± 30 µg/g, p = 0.003) and TADA (282 ± 50 µg/g, p = 0.003), in line with a reduction of the hepatic stellate cell activation markers smooth-muscle actin and phosphorylated moesin. Liver transaminases decreased under RIO (AST: -36%; ALT: -32%) and TADA (AST: -24%; ALT: -27%) treatment. Hepatic interleukin 6 gene expression was reduced in the RIO group (-56%, p = 0.053). CONCLUSION: In a rodent model of biliary cirrhosis, the sGC stimulator RIO and the PDE-5 inhibitor TADA improved PHT. The decrease of sinusoidal vascular resistance was paralleled by a reduction in liver fibrosis and hepatic inflammation, while systemic haemodynamics were not affected.
Assuntos
Hipertensão Portal/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Inibidores da Fosfodiesterase 5/uso terapêutico , Guanilil Ciclase Solúvel/antagonistas & inibidores , Animais , Benzoatos/farmacologia , Benzoatos/uso terapêutico , Ductos Biliares/cirurgia , Modelos Animais de Doenças , Humanos , Hipertensão Portal/diagnóstico , Hipertensão Portal/etiologia , Hipertensão Portal/fisiopatologia , Ligadura/efeitos adversos , Cirrose Hepática/etiologia , Masculino , Inibidores da Fosfodiesterase 5/farmacologia , Pressão na Veia Porta/efeitos dos fármacos , Pressão na Veia Porta/fisiologia , Sistema Porta/efeitos dos fármacos , Sistema Porta/fisiopatologia , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Guanilil Ciclase Solúvel/metabolismo , Tadalafila/farmacologia , Tadalafila/uso terapêutico , Resistência Vascular/efeitos dos fármacos , Resistência Vascular/fisiologiaRESUMO
A mass of evidence has identified a promoting of nitric oxide (NO) production in endothelial cells using natural products as a potential strategy to prevent and treat hypertension. This study investigated whether the aqueous extract of Moringa oleifera leaves (MOE) could lower mean arterial pressure (MAP) and relax mesenteric arterial beds in rats via stimulating endothelium-derived NO production. Intravenous administration of MOE (1-30 mg/kg) caused a dose-dependent reduction in MAP in anesthetized rats. In rats pretreated with the NO-synthase inhibitor, Nω-nitro-L-arginine methyl ester (L-NAME, 30 mg/kg, i.v.), the effect of MOE on MAP was significantly reduced. MOE (0.001-3 mg) induced relaxation in methoxamine (10 µM) pre-contracted mesenteric arterial beds, which was abolished by endothelium denudation. This endothelium-dependent vasorelaxation was reduced by L-NAME (100 µM) or the NO-sensitive guanylyl cyclase inhibitor, 1H- [1,2,4]-oxadiazolo-[4,3-a]-quinoxalin-1-one (10 µM). In primary human pulmonary artery endothelial cells, MOE (3-30 µg/mL) induced NO production, which was inhibited by L-NAME (100 µM) pretreatment. These findings show that MOE stimulates the endothelium-derived NO release for driving its vasorelaxation to lower arterial blood pressure. These suggest the development of MOE as a natural antihypertensive supplement.
Assuntos
Pressão Arterial/efeitos dos fármacos , Artérias/efeitos dos fármacos , Moringa oleifera/química , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/biossíntese , Extratos Vegetais/farmacologia , Resistência Vascular/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Masculino , Relaxamento Muscular/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Ratos , Ratos Wistar , Guanilil Ciclase Solúvel/antagonistas & inibidores , Circulação Esplâncnica/efeitos dos fármacosRESUMO
BACKGROUND: Endothelial dysfunction in the nitric oxide-cyclic guanosine monophosphate pathway is a potential contributor to perioperative myocardial ischemia. The nitric oxide precursor, L-arginine, and the cyclic guanosine monophosphate degradation blocker, sildenafil, have vasodilatory effects under high dosage. OBJECTIVE: This study examined the hemodynamic safety and effect profiles of the combined administration of L-arginine and sildenafil using an in-vivo pig model. METHODS: Hemodynamic safety including mean arterial pressure, central venous pressure, heart rate, coronary vascular resistance, and systemic vascular resistance, as well as effect profiles including cardiac output and left anterior descending blood flow were measured in ten female swine after administrations of L-arginine, sildenafil, as well as combined L-arginine and sildenafil. Measurements were compared using repeated-measures analysis of variance and linear mixed models. RESULTS: The combination of L-arginine and sildenafil produced a significant dose-dependent increase in left anterior descending flow and cardiac output. In contrast, mean arterial pressure, heart rate, central venous pressure, coronary vascular resistance, and systemic vascular resistance did not show any significant changes. No significant change in serum osmolality was observed after administrations of L-arginine. CONCLUSIONS: The combined intravenous administration of sildenafil and L-arginine in a porcine animal model was safe, well tolerated, and had at least additive effects on left anterior descending artery blood flow. Simultaneous application of both drugs might have dose-sparing effects leading to desired coronary effects at lower and safer sildenafil and L-arginine plasma concentrations. Hyperosmolality was only a minor factor in L-arginine hemodynamic effects.
Assuntos
Arginina/administração & dosagem , Arginina/efeitos adversos , Quimioterapia Combinada/efeitos adversos , Citrato de Sildenafila/administração & dosagem , Citrato de Sildenafila/efeitos adversos , Vasodilatadores/administração & dosagem , Vasodilatadores/efeitos adversos , Administração Intravenosa , Animais , Arginina/uso terapêutico , Circulação Coronária/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Modelos Animais , Citrato de Sildenafila/uso terapêutico , Suínos , Resistência Vascular/efeitos dos fármacos , Vasodilatadores/uso terapêuticoRESUMO
BACKGROUNDS/AIMS: The present study explores the potential of chronic treatment with the Foresaid X receptor (FXR) agonist obeticholic acid (OCA), which inhibits oxidative stress-related pathogenesis, in ascitic cirrhotic rats with hepatorenal syndrome (HRS) developed 6 weeks after bile duct ligation (BDL). METHODS: Systemic, splanchnic, and renal hemodynamics and pathogenic cascades were measured in ascitic BDL and sham rats receiving 2-weeks of either vehicle or OCA treatments (sham-OCA and BDL-OCA groups), and NRK-52E cells, rat kidney tubular epithelial cells. RESULTS: Chronic OCA treatment significantly normalized portal hypertension, glomerular filtration rate, urine output, renal blood flow; decreased ascites, renal vascular resistance, serum creatinine, and the release of renal tubular damage markers, including urinary neutrophil gelatinase-associated lipocalin (uNGAL) and kidney injury moleculae-1 (uKim-1) in BDL-OCA rats. In the BDL group, inhibition of the renal oxidative stress (8-iso-PGF2α)-activated cyclooxygenase-thromboxane A2 [COX-TXA2] pathway, apoptosis, and tubular injury accompanied by a decrease in hyper-responsiveness to the vasoconstrictor 8-iso-PGF2α in perfused kidneys. In vitro experiments revealed that 8-iso-PGF2α induced oxidative stress, release of reactive oxygen species, and cell apoptosis, which were reversed by concomitant incubation with the FXR agonist. CONCLUSIONS: Through the inhibition of renal 8-iso-PGF2α production and the down-regulation of the COX-TXA2 pathway, our study suggests that chronic OCA treatment can ameliorate the HRS in ascitic cirrhotic rats. Thus, OCA is an agent with antioxidative stress, antivasoconstrictive, antiapoptotic properties which benefit ascitic, cirrhotic rats with systemic, hepatic, and renal abnormalities.
Assuntos
Ácido Quenodesoxicólico/análogos & derivados , Síndrome Hepatorrenal/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Ácido Quenodesoxicólico/farmacologia , Ácido Quenodesoxicólico/uso terapêutico , Dinoprosta/análogos & derivados , Dinoprosta/metabolismo , Avaliação Pré-Clínica de Medicamentos , Glutationa/metabolismo , Síndrome Hepatorrenal/etiologia , Cirrose Hepática/complicações , Masculino , Ratos Sprague-Dawley , Receptores Citoplasmáticos e Nucleares/agonistas , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Tromboxano A2/metabolismo , Resistência Vascular/efeitos dos fármacosRESUMO
AIMS: Vitamin E (Vit-E) may preferentially improve cardiovascular risk in haptoglobin 2-2 (Hp2-2) genotype diabetes individuals. We studied the impact of Vit-E supplementation on vascular function in diabetes individuals stratified by haptoglobin genotype in Singapore. METHODS: In this 24-week, double blind, placebo-controlled RCT, we recruited 187 subjects (101 Hp2-2, 86 non-Hp2-2). INTERVENTION: alpha-tocopherol-400 IU. PRIMARY OUTCOME: Change in EndoPAT-derived reactive-hyperaemia index (RHI) and augmentation index (AIx); Secondary Outcomes: Pulse-Wave velocity (Sphygmocor-PWV), carotid intima media thickness (CIMT), inflammation (hsCRP), derivatives of reactive-oxygen metabolites (dROMs), biological antioxidant-potential (BAPs), HbA1c, LDL-C, HDL-C and oxidised LDL-C (ox-LDL). RESULTS: Overall, with Vit-E supplementation no significant change in RHI, PWV, CIMT, hsCRP, dROMS, BAPs, HDL-C and HbA1c was observed (p > 0.05); an increase in LDL-C with concomitant decrease in ox-LDL, and incidentally increase in eGFR was observed (p < 0.05). No interaction effect with haptoglobin genotype was seen for all outcomes (p > 0.05). Subgroup analysis: In the non-Hp-2-2 group, Vit-E supplementation led to a higher EndoPAT-derived AIx, accompanied by higher LDL and ox-LDL concentrations (p < 0.05); Hp2-2 group: Vit-E supplementation led to higher eGFR when compared to the non-Hp2-2 group (exploratory) (p < 0.05). We observed an interaction effect for baseline haptoglobin concentration (threshold > 119 mg/dl) with intervention in terms of increased EndoPAT-derived AIx in the Hp > 119 mg/dl group whereas no change in the group with Hp ≤ 119 mg/dl. CONCLUSION: Vit-E supplementation did not show any preferential benefit or deleterious effect on vascular function in Hp2-2 diabetes subjects in Singapore. A possible deleterious effect of an increase in arterial stiffness in individuals with Hp > 119 mg/dl was observed. Future studies should consider personalisation based on baseline Hp concentrations in patients with T2DM rather than just Hp2-2 genotype to evaluate impact on the detailed lipid pathways, cardiac and renal physiology. The impact of ethnic differences needs to be explored in greater details.
Assuntos
Circulação Sanguínea/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Haptoglobinas/genética , Resistência Vascular/efeitos dos fármacos , Vitamina E/administração & dosagem , Idoso , Antioxidantes/administração & dosagem , Espessura Intima-Media Carotídea , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Genótipo , Haptoglobinas/metabolismo , Humanos , Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , SingapuraRESUMO
BACKGROUND: Acupuncture has long been used for asthma treatment but the underlying mechanism remains unclear. Previous study showed that metallothionein-2 (MT-2) was significantly decreased in asthmatic lung tissue. However, the relationship between acupuncture treatment and MT-2 expression during asthma is still unknown, and the detailed effect analysis of MT-2 on phosphorylation in airway smooth muscle cells (ASMCs) is also unclear. METHODS: The acupuncture effect on pulmonary resistance (RL) was investigated in a rat model of asthma, and the mRNA and protein levels of MT-2 in lung tissue were detected. Primary ASMCs were isolated and treated with MT-2 recombinant protein to study the MT-2 effects on ASMC relaxation. A Phospho Explorer antibody microarray was applied to detect protein phosphorylation changes associated with MT-2-induced ASMC relaxation. Bioinformatic analysis were performed with PANTHER database, DAVID and STRING. Phosphorylation changes in key proteins were confirmed by Western blot. RESULTS: Acupuncture significantly reduced RL at 2-5â¯min (Pâ¯<â¯0.05 vs asthma) in asthmatic rats. Acupuncture continued to increase MT-2 mRNA expression in lung tissue for up to 14 days (Pâ¯<â¯0.05 vs asthma). The MT-2 protein expression was significantly decreased in the asthmatic rats (Pâ¯<â¯0.05 vs control), while MT-2 protein expression was significantly increased in the asthmatic model group treated with acupuncture (Pâ¯<â¯0.05 vs asthma). Primary ASMCs were successfully isolated and recombinant MT-2 protein (100, 200, 400â¯ng/ml) significantly relaxed ASMCs (Pâ¯<â¯0.05 vs control). MT-2 induced phosphorylation changes in 51 proteins. Phosphorylation of 14 proteins were upregulated while 37 proteins were downregulated. PANTHER classification revealed eleven functional groups, and the phosphorylated proteins were identified as transferases (27.8 %), calcium-binding proteins (11.1 %), etc. DAVID functional classification showed that the phosphorylated proteins could be attributed to eight functions, including protein phosphorylation and regulation of GTPase activity. STRING protein-protein interaction network analysis showed that Akt1 was one of the most important hubs for the phosphorylated proteins. The phosphorylation changes of Akt1 and CaMK2ß were consistent in both the Phospho Explorer antibody microarray and Western blot. CONCLUSION: Acupuncture can significantly ameliorate RL, and the MT-2 mRNA and protein levels in lung tissue are increased during treatment. MT-2 significantly relaxes ASMCs and induces a series of protein phosphorylation. These phosphorylation changes, including Akt1 and CaMK2ß, may play important roles in the therapeutic effects of acupuncture on asthma.
Assuntos
Terapia por Acupuntura , Asma/fisiopatologia , Asma/terapia , Pulmão/fisiopatologia , Metalotioneína/metabolismo , Animais , Asma/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Pulmão/metabolismo , Masculino , Metalotioneína/genética , Relaxamento Muscular , Miócitos de Músculo Liso/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Resistência VascularRESUMO
OBJECTIVE: This study aimed to investigate the effect of nifedipine on radial artery (RA) relaxation before puncture for coronary intervention. METHODS: In all, 120 patients were randomly assigned to nifedipine or control group. The diameter, resistance index (RI), and peak systolic velocity (PSV) of the RA were observed at 5, 15, and 30 min after nifedipine administration by a Doppler ultrasound examination. RESULTS: The greatest effect on RA diameter, PSV and resistance index (RI) was observed 5 minutes after sublingual nifedipine administration. The RA parameter were associated with the baseline diameter. CONCLUSIONS: Sublingual nifedipine administration before RA puncture has an obvious dilatation effect on small diameter RAs.
Assuntos
Nifedipino/uso terapêutico , Intervenção Coronária Percutânea/métodos , Pré-Medicação , Artéria Radial/cirurgia , Vasodilatadores/uso terapêutico , Administração Sublingual , Pressão Arterial , Velocidade do Fluxo Sanguíneo , Frequência Cardíaca , Humanos , Punções , Ultrassonografia Doppler , Resistência VascularRESUMO
The purpose of the present study was to analyze the actions of transient receptor potential vanilloid type 1 (TRPV1) agonist capsaicin (CS) and of its antagonist capsazepine (CZ), on cardiac function as well as endothelial biomarkers and some parameters related with nitric oxide (NO) release in L-NG-nitroarginine methyl ester (L-NAME)-induced hypertensive rats. NO has been implicated in the pathophysiology of systemic arterial hypertension (SAHT). We analyzed the levels of nitric oxide (NO), tetrahydrobiopterin (BH4), malondialdehyde (MDA), total antioxidant capacity (TAC), cyclic guanosin monophosphate (cGMP), phosphodiesterase-3 (PDE-3), and the expression of endothelial nitric oxide synthase (eNOS), guanosine triphosphate cyclohydrolase 1 (GTPCH-1), protein kinase B (AKT), and TRPV1 in serum and cardiac tissue of normotensive (118±3 mmHg) and hypertensive (H) rats (165 ± 4 mmHg). Cardiac mechanical performance (CMP) was calculated and NO was quantified in the coronary effluent in the Langendorff isolated heart model. In hypertensive rats capsaicin increased the levels of NO, BH4, cGMP, and TAC, and reduced PDE-3 and MDA. Expressions of eNOS, GTPCH-1, and TRPV1 were increased, while AKT was decreased. Capsazepine diminished these effects. In the hypertensive heart, CMP improved with the CS treatment. In conclusion, the activation of TRPV1 in H rats may be an alternative mechanism for the improvement of cardiac function and systemic levels of biomarkers related to the bioavailability of NO.
Assuntos
Coração/efeitos dos fármacos , Hipertensão/metabolismo , Miocárdio/metabolismo , Óxido Nítrico/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Biomarcadores/sangue , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Pressão Sanguínea , Capsaicina/análogos & derivados , Capsaicina/farmacologia , Capsaicina/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Hipertensão/tratamento farmacológico , Masculino , NG-Nitroarginina Metil Éster , Óxido Nítrico Sintase Tipo III , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt , Ratos , Ratos Wistar , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/antagonistas & inibidores , Resistência VascularRESUMO
INTRODUCTION: Many women undergoing coronary angiography for chest pain have no or only minimal coronary artery disease (CAD). However, despite the lack of obstructive CAD, they still have an increased risk of major adverse cardiovascular events. Pleiotropic effects of statins may influence microvascular function, but if statins improve microvascular function in unselected chest pain patients is not well studied. This study assessed microvascular function by using the thermodilution-derived test "the index of microvascular resistance" (IMR) with the aim of determining the (i) IMR level in women with chest pain and non-obstructive CAD and if (ii) IMR is modified by high-dose statin treatment in these patients. Additional objectives were to identify the influence of statins on the health status as assessed with generic health questionnaires and on biomarkers of endothelial activation. MATERIALS AND METHODS: The study was a randomized, double-blind, single-center trial comparing 6 months of rosuvastatin treatment with placebo. In total, 66 women without obstructive CAD were included. Mean age was 52.7 years and 55.5 years in the placebo and rosuvastatin group, respectively. Microvascular function was assessed using the IMR, health status was assessed using the SF-36 and EQ-5D questionnaires, and biochemical values were assessed at baseline and 6 months later. RESULTS AND CONCLUSIONS: In the placebo group IMR was 14.6 (SD 5.7) at baseline and 14.4 (SD 6.5) at follow-up. In the rosuvastatin group IMR was 16.5 (SD 7.5) at baseline and 14.2 (SD 5.8) at follow-up. IMR did not differ significantly between the two study groups at follow-up controlled for preintervention values. C-reactive protein (CRP) was comparable between the groups at baseline, while at follow-up CRP was significantly lower in the rosuvastatin group compared to placebo [0.6 (±0.5) mg/L vs. 2.6 (±3.0) mg/L; p = 0.002]. Whereas rosuvastatin treatment for 6 months attenuated CRP levels, it did not improve microvascular function as assessed by IMR (Clinical Trials.gov NCT01582165, EUDRACT 2011-002630-39.3tcAZ).
Assuntos
Circulação Coronária/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Microcirculação/efeitos dos fármacos , Angina Microvascular/tratamento farmacológico , Rosuvastatina Cálcica/administração & dosagem , Resistência Vascular/efeitos dos fármacos , Adulto , Idoso , Método Duplo-Cego , Feminino , Nível de Saúde , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Angina Microvascular/diagnóstico , Angina Microvascular/fisiopatologia , Pessoa de Meia-Idade , Noruega , Projetos Piloto , Rosuvastatina Cálcica/efeitos adversos , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Luehea divaricata Mart. (Malvaceae) is an important medicinal species widely used by indigenous and riverside populations of the Brazilian Pantanal region. It has been shown that the several extracts obtained from leaves of this species have important cardioprotective effects. Nevertheless, the secondary metabolites responsible for this activity, as well as the molecular mechanisms responsible for their pharmacological effects remain unknown. PURPOSE: To carry out a biomonitoring study to identify possible active metabolites present in different ESLD fractions and evaluate the mechanisms responsible for the vasodilatory effects on isolated perfused mesenteric beds. METHODS: First, ESLD was obtained from L. divaricata leaves and a liquid-liquid fractionation was performed. The resulting fractions were analyzed by liquid chromatography-mass spectrometry. Then, the possible vasodilatory effects of ESLD, chloroform, ethyl acetate, n-butanolic and aqueous fractions on perfused arterial mesenteric vascular beds were evaluated. Finally, the molecular mechanisms involved in vasodilator responses of the aqueous fraction and its chemical component, isovitexin, on the mesenteric arteriolar tone were also investigated. RESULTS: In preparations with functional endothelium ESLD, n-butanolic, aqueous fraction and isovitexin dose-dependently reduced the perfusion pressure in mesenteric vascular beds. Endothelium removal or inhibition of nitric oxide synthase enzymes by L-NAME reduced the vasodilatory effects induced by aqueous fraction and isovitexin. Perfusion with nutritive solution containing 40 mM KCl abolished the vasodilatory effect of all aqueous fractions and Isovitexin doses. Treatment with glibenclamide, a Kir6.1 (ATP-sensitive) potassium channels blocker, tetraethylammonium, a non-selective KCa (calcium-activated) potassium channels blocker, or apamin, a potent blocker of small conductance Ca2+-activated (SK KCa) potassium channels reduced by around 70% vasodilation induced by all aqueous fractions and isovitexin doses. In addition, association of tetraethylammonium and glibenclamide, or L-NAME and glibenclamide, fully inhibited aqueous fraction and Isovitexin -induced vasodilation. CONCLUSION: This study showed that AqueFr obtained from Luehea divaricata and its metabolite - isovitexin - has important vasodilatory effects on MVBs. Apparently, these effects are dependent on endothelium-NO release and both SK KCa K+ channels and Kir6.1 ATP-sensitive K+ channels activation in the vascular smooth muscle.