Protective effects of Ruscus extract in combination with ascorbic acid and hesperidine methylchalcone on increased leukocyte-endothelial interaction and macromolecular permeability induced by ischemia reperfusion injury.

Background: Despite the well-recognized effectiveness of Ruscus aculetus extract combined or not with ascorbic acid (AA) and hesperidine methyl chalcone (HMC) on ischemia reperfusion (I/R) injury protection, little is known about the contribution of each constituent for this effect.

Objective: To investigate the effects of AA and HMC combined or not with Ruscus extract on increased macromolecular permeability and leukocyte-endothelium interaction induced by I/R injury.

Methods: Hamsters were treated daily during two weeks with filtered water (placebo), AA (33, 100 and 300 mg/kg/day) and HMC (50, 150 and 450 mg/kg/day) combined or not with Ruscus extract (50, 150 and 450 mg/kg/day).

Peripheral microvascular dysfunction is also present in patients with ischemia and no obstructive coronary artery disease (INOCA).

Background: In patients with ischemia and no obstructive coronary artery disease (INOCA), coronary microvascular dysfunction is associated with higher rate of major adverse cardiovascular events.

Objective: To demonstrate if microvascular dysfunction present in coronary microcirculation of patients with INOCA may be detected noninvasively in their peripheral circulation.

Methods: 25 patients with INOCA and 25 apparently healthy individuals (controls) were subjected to nailfold videocapillaroscopy (NVC) and venous occlusion plethysmography (VOP) to evaluate peripheral microvascular function and blood collection for biomarkers analysis, including soluble vascular cell adhesion molecule-1 (sVCAM-1), endothelin-1 (ET-1) and C-reactive protein (CRP).

Effects of Ruscus extract on muscarinic receptors: Is there a role for endothelium derived relaxing factors on macromolecular permeability protection and microvascular diameter changes?

Background: Protective effects of Ruscus extract on macromolecular permeability depend on its capacity to stimulate muscarinic receptors on endothelial cells and induce the release of endothelium derived relaxing factors (EDRFs).

Objective: To investigate if these effects depend only on activation of muscarinic receptors or if EDRFs release are also necessary. We have also investigated the participation of Ruscus extract on muscarinic-induced release of EDRFs on microvascular diameters.

Obesity blunts cephalic-phase microvascular responses to food.

Neurally mediated anticipatory responses, also named cephalic-phase responses, and microcirculatory regulation are two important mechanisms to maintain metabolic homeostasis. Altered cephalic-phase responses in obesity and its metabolic consequences have been proposed. There is, however, a lack of studies focusing on in vivo assessment of the microcirculation during this phase in patients with obesity.

Clinical and laboratory markers associated with anti-TNF-alpha trough levels and anti-drug antibodies in patients with inflammatory bowel diseases.

Monitoring anti-TNF agents in inflammatory bowel disease (IBD) patients may be helpful in optimizing outcomes. We aimed to evaluate potential correlations among demographic, clinical, laboratory, or imaging parameters, as well as serum levels of infliximab (IFX) and adalimumab (ADA) and their respective antibodies, in the clinical management of IBD patients.A cross-sectional study of 95 patients with Crohn's disease (CD) or ulcerative colitis (UC) in maintenance therapy with infliximab or adalimumab was performed.

Dissociation between macro- and microvascular parameters in the early phase of hemorrhagic shock.

Hemorrhagic shock (HS) therapy is based on macrohemodynamic improvement, but it is not clear if this therapy correlates directly with increases in tissue perfusion. Aiming to clarify this point, we compared norepinephrine (NE, a vasoconstrictor), sodium nitroprusside (NP, a vasodilator) and levosimendan (LEV, an inodilator) treatments on macro and microvascular parameters using the hamster dorsal skinfold chamber preparation. One hour after HS, animals received Ringer's lactate (RL) solution within 10 min, then animals received RL, NP, NE and LEV during 90 min via jugular vein.

Dipeptidyl Peptidase 4 Activity Is Related to Body Composition, Measures of Adiposity, and Insulin Resistance in Subjects with Excessive Adiposity and Different Degrees of Glucose Tolerance.

Background: The enzyme dipeptidyl peptidase 4 (DPP4) has been recently recognized as an adipo-myokine. However, studies that associate its constitutive activity with body composition, anthropometry, and insulin resistance (IR) are very scarce and included only healthy people.

Methods: First, we investigated the relationships of constitutive DPP4 activity, body composition (assessed by bioelectrical impedance analysis), and measures of adiposity and IR in fifty-two subjects of both sexes, 18-50 years, and BMI ≥25.

Effects of Selenium in the Microcirculation of Fructose-Fed Hamsters.

Background And Aims: Fructose intake is directly related to vascular dysfunction and it is a risk factor for the development of metabolic and cardiovascular diseases, such as obesity, diabetes, and hypertension. Selenium, a component of antioxidant enzymes, improves hyperglycemia and vascular function in diabetic animals. The aim of this study was to evaluate the effects of dietary selenium supplementation on microcirculatory and metabolic parameters of fructose-fed hamsters.

Microcirculation and biomarkers in patients with resistant or mild-to-moderate hypertension: a cross-sectional study.

Microcirculation influences peripheral vascular resistance and therefore contributes to arterial blood pressure. The aim of this study was to investigate the correlation between serum markers of inflammation and microcirculatory parameters observed by nailfold videocapillaroscopy (NVC) in patients with resistant (RH, 58 [50-63] years, n = 25) or mild-to-moderate hypertension (MMH, 56 [47-64] years, n = 25) compared to normotensive patients (control group (CG), 33 [27-52] years, n = 25). C-reactive protein (CRP), endothelin, adiponectin, I-CAM and V-CAM levels were obtained by laboratory analysis.

Evaluation of endothelial function by VOP and inflammatory biomarkers in patients with arterial hypertension.

Hypertension is associated with microcirculatory impairment. Our objectives were to evaluate endothelial function and inflammatory biomarkers in patients with resistant (RH) and mild to moderate (MMH) arterial hypertension in comparison to normotensives (control group-CG). Three groups, 25 patients each, have been investigated, by anamnesis, venous occlusion plethysmography (VOP) and serum determination of adhesion molecules (VCAM, ICAM), adiponectin, endothelin and C-reactive protein (CRP).

Increment of body mass index is positively correlated with worsening of endothelium-dependent and independent changes in forearm blood flow.

Obesity is associated with the impairment of endothelial function leading to the initiation of the atherosclerotic process. As obesity is a multiple grade disease, we have hypothesized that an increasing impairment of endothelial and vascular smooth muscle cell functions occurs from lean subjects to severe obese ones, creating a window of opportunities for preventive measures. Thus, the present study was carried out to investigate the grade of obesity in which endothelial dysfunction can be detected and if there is an increasing impairment of endothelial and vascular smooth muscle cell functions as body mass index increases.

α-Tocopherol Improves Microcirculatory Dysfunction on Fructose Fed Hamsters.

Fructose, an everyday component of western diet associated to chronic hyperglycemia and enhanced free radical production, impairs endothelial function and supplementation with antioxidants might improve it. In this study we investigated if vitamin E could reverse the microvascular damage elicited by fructose. Male Syrian golden hamsters drank either 10% fructose solution (F) or filtered water (C), combined with three concentrations of vitamin E in their chows [zero, normal (VE) or 5X (5XVE)] during 60 days.

Beneficial effects of the micronized purified flavonoid fraction (MPFF, Daflon® 500 mg) on microvascular damage elicited by sclerotherapy.

Objectives: To evaluate if the micronized purified flavonoid fraction (MPFF) treatment could reduce the side effects of sclerotherapy (a procedure frequently used to treat venous disease manifestations) by minimizing the inflammatory response within the surrounding tissues.

Method: Twenty-two male New Zealand rabbits were treated by gavage with micronized purified flavonoid fraction (MPFF; 300 mg/kg/day) or vehicle (10% lactose solution) during 21 consecutive days, starting 7 days before sclerotherapy. The sclerotherapy consisted of an injection containing 5% ethanolamine oleate solution in the rabbit's dorsal ear vein.

Chronic aerobic exercise associated to dietary modification improve endothelial function and eNOS expression in high fat fed hamsters.

Obesity is epidemic in the western world and central adipose tissue deposition points to increased cardiovascular morbidity and mortality, independently of any association between obesity and other cardiovascular risk factors. Physical exercise has been used as non-pharmacological treatment to significantly reverse/attenuate obesity comorbidities. In this study we have investigated effects of exercise and/or dietary modification on microcirculatory function, body composition, serum glucose, iNOS and eNOS expression on 120 male hamsters treated for 12 weeks with high fat chow (HF, n = 30) starting on the 21st day of birth.

Arteriolar diameter and spontaneous vasomotion: importance of potassium channels and nitric oxide.

Arterioles display cyclic variations in diameter, termed vasomotion initiated by smooth muscle cells (SMCs), but the endothelium should also be evaluated due to its modulatory role on vessel tone. Since nitric oxide (NO) and prostacyclin (PGI2) regulate SMC tone and activate K(+) currents, we have investigated their role on vasomotion, by observing effects of topical application of N(ω)-nitro-l-arginine (L-NA, NO synthesis inhibitor), glibenclamide (KATP channel inhibitor), sodium nitroprusside (SNP, NO donor), iloprost (PGI2 analogue) and methylene blue (MB, cGMP production inhibitor) on the cheek pouch preparation of anesthetized male hamsters. L-NA (10(-10)-10(-6)M) induced vasoconstriction, reduction and abolition of vasomotion.

Effects of babassu nut oil on ischemia/reperfusion-induced leukocyte adhesion and macromolecular leakage in the microcirculation: observation in the hamster cheek pouch.

Background: The babassu palm tree is native to Brazil and is most densely distributed in the Cocais region of the state of Maranhão, in northeastern Brazil. In addition to the industrial use of refined babassu oil, the milk, the unrefined oil and the nuts in natura are used by families from several communities of African descendants as one of the principal sources of food energy. The objective of this study was to evaluate the effects of babassu oil on microvascular permeability and leukocyte-endothelial interactions induced by ischemia/reperfusion using the hamster cheek pouch microcirculation as experimental model.

Novel findings in the cephalic phase of digestion: a role for microcirculation?

The cephalic phase of digestion (CPD) has been extensively investigated in terms of digestion and metabolism. Nevertheless, microcirculatory changes required to prepare peripheral tissues in order to dispose nutrients have never been assessed. In this study, microvascular function has been evaluated to determine its behavior and potential association to hormonal secretions during CPD.

High fat diet induces central obesity, insulin resistance and microvascular dysfunction in hamsters.

Microvascular dysfunction is an early finding in obesity possibly related to co-morbidities like diabetes and hypertension. Therefore we have investigated changes on microvascular function, body composition, glucose and insulin tolerance tests (GTT and ITT) on male hamsters fed either with high fat (HFD, n=20) or standard (Control, n=21) diet during 16 weeks. Total body fat and protein content were determined by carcass analysis, aorta eNOS and iNOS expression by immunoblotting assay and mean blood pressure (MAP) and heart rate (HR) by an arterial catheter.

Substitution of drinking water by fructose solution induces hyperinsulinemia and hyperglycemia in hamsters.

Purpose: To test the possibility of obtaining a practical and stable model of hyperinsulinemia and hyperglycemia in hamsters, substituting the drinking water by 10% or 20% fructose solutions for a period of 2, 4, or 6 months.

Methods: Male hamsters were divided into 3 main groups, further divided in 3 subgroups: Two months: Group Ia control (n = 51) received filtered water, Group Ib (n = 49) received 10% fructose solution instead of water, Group Ic (n=8) received 20% fructose solution instead of water. Four months: Group IIa control (n=8), Group IIb 10% fructose (n = 7), Group IIc 20% fructose (FIIc, n = 7).