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Energy drinks are nonalcoholic beverages whose main ingredients are sugar, taurine, and caffeine. The consumption of energy drinks is increasing worldwide, but only a few conflicting studies have investigated the vascular effects of energy drinks in young adults. The aim of this study was to evaluate microvascular reactivity before and after energy drinks consumption in young healthy male volunteers. This was a cross-sectional prospective study. Microvascular reactivity signals were evaluated in the skin of the forearm using laser speckle contrast imaging with acetylcholine (ACh) iontophoresis before and 90 and 180 min after the randomized consumption of one ED or the same volume of water (control), followed by a postocclusive reactive hyperemia (PORH) test. Thirty-two volunteers were evaluated (age: 25.4±4.3 years). Energy drink consumption prevented the rest-induced reduction in cutaneous vascular conductance over time that was observed in the control group. In the control group, there were significant reductions in microvascular vasodilation at 90 and 180 min compared to baseline (P=0.004), but this was not the case in the energy drink group (P=0.76). Our results demonstrated that the reduction in microvascular conductance associated with prolonged immobility can be prevented by the consumption of one energy drink, highlighting the vasodilator effects of this beverage in young individuals at rest. The between-study variability in terms of the brand of energy drinks and the ingested volume, as well as the method of vascular evaluation and the inclusion criteria, may explain the discrepancies among previous studies on the vascular effects of energy drinks.
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BACKGROUND: This study aimed to evaluate whether soluble vascular cytoadhesive molecule-1 (sVCAM-1), intracellular cytoadhesive molecule-1 (sICAM-1), and endothelial function as assessed by EndoPat outweighed traditional risk factors for the presence of diabetic retinopathy (DR) in patients with type 1 diabetes (T1D). METHODS: Patients aged ≥ 12 years completed a clinical-epidemiological questionnaire. Fasting venous blood samples were obtained (lipid profile, glycemic control, and C-reactive protein levels). Vascular reactivity was assessed via peripheral arterial tonometry performed by supplying the reactive hyperemia index (RHI) through the EndoPAT device. sVCAM-1 and sICAM-1 levels were measured using multiplex assays. RESULTS: Data were obtained from 187 patients (51.3% female), aged 32 ± 13 years with a disease duration of 14 (6-15) years and mean hemoglobin A1c (HbA1c) of 9.1% ± 2.1%. After adjustments were made, age, HbA1c, arterial blood pressure, and use of drugs that could interfere with endothelial function were found to be associated with DR. No association was noted with sVCAM-1 and sICAM-1 levels and RHI. CONCLUSIONS: In our sample, sVCAM-1, sICAM and EndoPAT did not outweigh the traditional DR risk factors, such as age, high HbA1c, arterial blood pressure, and use of drugs that could interfere with endothelial function and are significantly associated with DR. Further prospective studies should evaluate if markers of endothelial dysfunction could predict diabetes-related micro and macrovascular complications in T1D.
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Endothelial dysfunction is a well-known component of the pathophysiology of heart failure (HF), with proven prognostic value. Dietary supplementation with whey protein (WP) has been widely used to increase skeletal muscle mass, but it also has vascular effects, which are less understood. This study aimed to evaluate the effects of WP supplementation on the systemic microvascular function of HF patients. This was a blinded, randomized, placebo-controlled clinical trial that evaluated the effects of 12-week WP dietary supplementation on systemic microvascular function, in patients with HF New York Heart Association (NYHA) classes I/II. Cutaneous microvascular flow and reactivity were assessed using laser speckle contrast imaging, coupled with pharmacological local vasodilator stimuli. Fifteen patients (aged 64.5±6.2 years, 11 males) received WP supplementation and ten patients (aged 68.2±8.8 years, 8 males) received placebo (maltodextrin). The increase in endothelial-dependent microvascular vasodilation, induced by skin iontophoresis of acetylcholine, was improved after WP (P=0.03) but not placebo (P=0.37) supplementation. Moreover, endothelial-independent microvascular vasodilation induced by skin iontophoresis of sodium nitroprusside, was also enhanced after WP (P=0.04) but not placebo (P=0.42) supplementation. The results suggested that dietary supplementation with WP improved systemic microvascular function in patients with HF.
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Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Vasodilatação , Insuficiência Cardíaca/tratamento farmacológico , Pele , Vasodilatadores/farmacologia , Endotélio Vascular , Projetos Piloto , Suplementos Nutricionais , Proteínas do Soro do Leite/farmacologia , MicrocirculaçãoRESUMO
COVID-19, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), while having lung injury as its most prominent feature, has been increasingly shown to affect endothelial cell function and the microvasculature. In this report, a woman with COVID-19, cardiac valve disease and spherocytosis was assessed with laser Doppler perfusion monitoring. Systemic microvascular reactivity was impaired during a worsening phase of COVID-19, but improved after clinical recovery; microcirculatory dysfunction paralleled systemic inflammation and pulmonary involvement. The assessment of systemic microcirculatory function may therefore provide insights on COVID-19 pathophysiology.
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OBJECTIVE: Adults with congenital heart disease share some features with those with chronic heart failure. Although microvascular endothelial dysfunction has been described in chronic heart failure, evaluation of the microcirculation in adults with congenital heart disease is lacking. The present study aimed to investigate systemic microvascular reactivity in adults with congenital heart disease. INTERVENTIONS: The patients initially underwent cardiopulmonary exercise testing. Then, the cutaneous microvascular reactivity was evaluated in these patients using a laser speckle contrast imaging system coupled with skin iontophoresis of endothelial-dependent (acetylcholine) or -independent (sodium nitroprusside) vasodilators and postocclusive reactive hyperemia (PORH) and compared with healthy controls matched for age and sex. RESULTS: Thirty-one patients and 29 healthy controls were evaluated. The basal microvascular flow (P < .0001) and area under the curve in response to acetylcholine (P < .0001) were higher in the patients than in the healthy volunteers. The increase in cutaneous vascular conductance in response to sodium nitroprusside was reduced in the patients compared to the healthy volunteers (P = .0031). No difference in the microvascular response was observed during postocclusive reactive hyperemia. The basal microvascular flow of patients with peak oxygen consumption below 16.0 mL kg-1 min-1 was superior to that of patients with values greater than 16.0 mL kg-1 min-1 (P = .0046). CONCLUSIONS: Adults with congenital heart disease present a higher baseline cutaneous microvascular blood flow than healthy controls and do not present systemic microvascular endothelial dysfunction. Nevertheless, endothelium-independent microvascular reactivity is blunted, suggesting an altered vascular smooth muscle response or vascular structural alterations. Finally, patients with a lower functional capacity presented a greater microvascular basal blood flow than subjects with a higher functional capacity.
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Endotélio Vascular/fisiopatologia , Cardiopatias Congênitas/fisiopatologia , Microcirculação/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Vasodilatação/fisiologia , Adulto , Capilares/fisiopatologia , Estudos Transversais , Teste de Esforço , Feminino , Cardiopatias Congênitas/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Nitroprussiato/farmacologia , Estudos Retrospectivos , Vasodilatadores/farmacologia , Adulto JovemRESUMO
BACKGROUND: Chronic venous disease of the lower limbs is a common public health problem worldwide with negative impact on quality of life and results with drugs used to treat it are sparse, probably due to lack of good experimental models. OBJECTIVE: In this investigation we have tested the effects of two commonly used venotonic substances, Ruscus extract and micronized diosmine, on the microcirculation in vivo. METHODS: These substances were given orally, by gavage, during two weeks, twice daily and observations were made using the hamster cheek pouch preparation. RESULTS: The drugs elicited a dose-dependent inhibition of (1) macromolecular permeability increase induced by histamine or ischemia followed by reperfusion, being the Ruscus extract more active on both and (2) leukocyte-endothelium interaction, again being the Ruscus extract more effective in the inhibition of the number of adherent and rolling leukocytes. About the duration of the effect after the end of the treatment, both drugs had similar effects but Ruscus extract showed greater permanence of its effect on all observed parameters. CONCLUSIONS: Our results suggest that both drugs have antioxidant and anti-inflammatory properties being Ruscus extract more active. It should be added that only Ruscus extract showed a significant venular constriction.
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Microcirculação/efeitos dos fármacos , Extratos Vegetais/química , Ruscus/química , Insuficiência Venosa/tratamento farmacológico , Animais , Feminino , MesocricetusRESUMO
No study has shown the effects of acute resistance exercise on vasodilatory capacity of patients with peripheral artery disease. The aim of this study was to analyse the effects of a single session of resistance exercise on blood flow, reactive hyperemia, plasma nitrite, and plasma malondialdehyde in patients with peripheral artery disease. Fourteen peripheral artery disease patients underwent, in a random order, 2 experimental sessions: control (rest for 30 min) and resistance exercise (8 exercises, 2 sets of 10 repetitions at an intensity of 5-7 in the OMNI Resistance Exercise Scale). Blood flow, reactive hyperemia, plasma nitrite, and malondialdehyde were measured before and 40 min after the interventions in both sessions. Data were compared between sessions by analysis of covariance, using pre-intervention values as covariates. The increases in blood flow, reactive hyperemia, and log plasma nitrite were greater (p ≤ 0.05) after resistance exercise than the control session (3.2 ± 0.1 vs. 2.7 ± 0.1 mL · 100 mL(-1) tissue · min(-1), 8.0 ± 0.1 vs. 5.7 ± 0.1 AU, and 1.36 ± 0.01 vs. 1.26 ± 0.01 µmol â L(-1), respectively). On the other hand, malondialdehyde was similar between sessions (p > 0.05). In peripheral arterial disease patients, a single session of resistance exercise increases blood flow and reactive hyperemia, which seems to be mediated, in part, by increases in nitric oxide release.
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Claudicação Intermitente/terapia , Perna (Membro)/irrigação sanguínea , Fluxo Sanguíneo Regional , Treinamento Resistido , Vasodilatação , Idoso , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Hiperemia/etiologia , Hipertensão/etiologia , Claudicação Intermitente/etiologia , Claudicação Intermitente/metabolismo , Claudicação Intermitente/fisiopatologia , Peroxidação de Lipídeos , Masculino , Malondialdeído/sangue , Microvasos/metabolismo , Microvasos/fisiopatologia , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Nitritos/sangue , Nitritos/metabolismo , Doença Arterial Periférica/fisiopatologia , Treinamento Resistido/efeitos adversosRESUMO
OBJECTIVES: Estrogen has been shown to play an important protective role in non-reproductive systems, such as the cardiovascular system. Our aim was to observe gender differences in vivo with regard to the increase in macromolecular permeability and leukocyte-endothelium interaction induced by ischemia/reperfusion as well as in microvascular reactivity to vasoactive substances using the hamster cheek pouch preparation. METHODS: Thirty-six male and 36 female hamsters, 21 weeks old, were selected for this study, and their cheek pouches were prepared for intravital microscopy. An increase in the macromolecular permeability of post-capillary venules was quantified as a leakage of intravenously injected fluorescein-labeled dextran, and the leukocyte-endothelium interaction was measured as the number of fluorescent rolling leukocytes or leukocytes adherent to the venular wall, labeled with rhodamin G, during reperfusion after 30 min of local ischemia. For microvascular reactivity, the mean internal diameter of arterioles was evaluated after the topical application of different concentrations of two vasoconstrictors, phenylephrine (α1-agonist) and endothelin-1, and two vasodilators, acetylcholine (endothelial-dependent) and sodium nitroprusside (endothelial-independent). RESULTS: The increase in macromolecular permeability induced by ischemia/reperfusion was significantly lower in females compared with males [19 (17-22) leaks/cm2 vs. 124 (123-128) leaks/cm2, respectively, p<0.001), but the number of rolling or adherent leukocytes was not different between the groups. Phenylephrine-induced arteriolar constriction was significantly lower in females compared with males [77 (73-102)% vs. 64 (55-69)%, p<0.04], but there were no detectable differences in endothelin-1-dependent vasoreactivity. Additionally, arteriolar vasodilatation elicited by acetylcholine or sodium nitroprusside did not differ between the groups. CONCLUSION: The ...
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Animais , Cricetinae , Feminino , Masculino , Sistema Cardiovascular/metabolismo , Estrogênios/metabolismo , Microcirculação/fisiologia , Acetilcolina/farmacologia , Permeabilidade Capilar , Adesão Celular/fisiologia , Bochecha/irrigação sanguínea , Endotélio Vascular/fisiologia , Leucócitos/fisiologia , Nitroprussiato/farmacologia , Fenilefrina/farmacologia , Traumatismo por Reperfusão/metabolismo , Fatores Sexuais , Fatores de TempoRESUMO
A fase cefálica de secreção de insulina (FCSI) ocorre dentro da fase cefálica da digestão, em aproximadamente dez minutos entre a estimulação oro-sensorial pelo alimento e o início da absorção deste e determina um incremento rápido dos níveis basais de insulina. A FCSI parece ser importante para a tolerância normal à glicose. A hipótese deste estudo é de que a insulina secretada na fase cefálica da digestão teria ações direcionadas para o tecido microvascular, com conseqüente recrutamento capilar. Estudos recentes com indivíduos sadios têm mostrado a associação entre função microvascular e componentes dietéticos. Padrões alimentares saudáveis e intervenções nutricionais com alimentos específicos representam estratégias preventivas e terapêuticas não-farmacológicas para redução da inflamação e do risco metabólico e cardiovascular associados. O estudo de consumo alimentar inserido nesta pesquisa objetivou identificar associações entre componentes dietéticos e a função microvascular em indivíduos saudáveis. Após avaliação clínica e laboratorial, 39 voluntários saudáveis foram submetidos a dois exames de videocapilaroscopia do leito ungueal, com um intervalo de dez minutos entre os mesmos. Neste intervalo, conforme randomização, uma refeição com ótima apresentação e aroma foi apresentada (estímulo sendorial) ou não (controle). Coletas sangüíneas foram realizadas aos 3, 9 e 15 minutos após a apresentação do estímulo, para avaliação dos níveis de insulina e polipeptídeo pancreático (PP), marcadores bioquímicos da fase cefálica da digestão. Durante todo o exame, medidas de fluxo e vasomotricidade foram realizadas pela técnica de laser-Doppler fluxometria. Após o exame, foi realizada iontoforese transdérmica de insulina. Todos os participantes responderam a um questionário de freqüência alimentar (QFA), relativo ao hábito de consumo dietético dos últimos 12 meses. O estudo da resposta microvascular à fase cefálica comparou as diferenças de densidade capilar...
The cephalic phase of insulin secretion (CPIS) occurs within the cephalic phase of digestion, in approximately ten minutes between the oral-sensorial stimulation elicited by the food to be consumed and the beginning of its absorption. It determines a rapid increase in insulin levels. The CPIS is believed to be important for normal glucose tolerance. The hypothesis of this study is that insulin secreted during cephalic phase would also have actions targeting microvascular tissue, with resulting capillary recruitment. Recent studies with healthy subjects have shown an association between microvascular function and dietary factors. Healthy eating patterns and nutritional interventions with specific food items represent non-pharmacological preventive and therapeutic strategies for reducing inflammation and cardio-metabolic associated risk factors. The study of food intake included in this research aimed to identify associations between dietary intake and microvascular function in healthy subjects. After clinical and laboratorial assessment, 39 healthy men underwent two nailfold videocapillaroscopies, with an interval of 10 minutes between them. In this interval, according to radomization, they were subjected to a great-looking breakfast tray (CPIS group) or to nothing (control group). Blood samples were drawn at 3, 9 and 15 minutes after the stimulus presentation to assess insulin and pancreatic polypeptide (PP) levels, which are markers of cephalic phase of digestion. Throughout the exam, microflow and vasomotion were measured by laser-Doppler flowmetry. After the exam insulin iontophoresis was performed. All participants answered a food-frequency questionnaire (FFQ) regarding their dietary intake in the last 12 months. The assessment of microvascular response to CPIS compared differences in functional capillary density (FCD) and microflow in the CPIS and control groups, pre- and post-stimulus and their correlations with changes in insulin and PP...