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- ItemInfluência dos capsinóides sobre a reatividade e estresse oxidativo vascular de ratos com obesidade(Universidade Federal do Espírito Santo, 2024-11-12) Cordeiro, Evellyn Rodrigues; Leopoldo, André Soares ; https://orcid.org/0000-0001-5999-2671; http://lattes.cnpq.br/5912424547697713; https://orcid.org/0009-0001-5847-2786; http://lattes.cnpq.br/8393859318309960; Santos, Roger Lyrio dos ; https://orcid.org/0000-0003-4316-7196; http://lattes.cnpq.br/1122196233280741; Nunes, Karolini Zuqui ; https://orcid.org/0000-0003-3433-4925; http://lattes.cnpq.br/6888896554912256; Camacho, Camila Renata Corrêa ; https://orcid.org/0000-0001-8493-5329; http://lattes.cnpq.br/8515265257310064; Nascimento, Thiago Bruder do ; https://orcid.org/0000-0001-5671-318X; http://lattes.cnpq.br/2679070556021956Obesity is one of the biggest public health problems and its pathophysiology involves metabolic, structural and functional changes in different tissues due to several mechanisms. Such changes can modify vascular homeostasis and are associated with the development of cardiovascular diseases such as arterial hypertension, coronary disease and atherosclerosis, as well as type 2 diabetes mellitus, which increase the risk of mortality. The deleterious effects observed in obesity include the process of dysfunctional vascular remodeling with consequent rigidity after structural and functional modifications in the intima, media and adventitial layers of blood vessels. In addition, oxidative stress, an important pathological mechanism involved in obesity, contributes to the development of pro-oxidant and pro-inflammatory states in the vasculature, which promote dysfunctional remodeling and vascular stiffness, increasing the risk of pathological outcomes observed in cardiovascular events. Studies have shown that capsinoids, bioactive peptides present in pepper, are potent antioxidants and antiobesogenics, playing a role in modulating oxidative stress induced by obesity. However, no research was found that analyzed their effects on oxidative stress and vascular remodeling caused by obesity. Therefore, the aim of the present study was to investigate the effects of chronic administration of capsinoids on vascular reactivity, morphology and oxidative stress in the aorta of obese rats induced by a saturated high-fat diet. Wistar rats (n=18, 30 days) were randomized into 2 groups: standard diet (fed with standard diet; DP = 8) and high-fat diet (fed with saturated diet rich in fat; DH = 10). Control = C (fed with standard diet) and obese = Ob (fed with saturated high-fat diet). The experimental protocol lasted 27 consecutive weeks, consisting of two moments: 1) Induction (4 weeks) and maintenance of obesity (19 weeks) and; 2) Chronic exposure to treatment with capsinoids (8 weeks). After 19 weeks, DP and DH animals were redistributed and randomly renamed into four distinct groups according to the absence and/or presence of capsinoids (Cap) and obesity (Ob): Control (C); Obese (Ob); Control with capsinoids (Ccap); Obese with capsinoids (ObCap). Chronic administration of capsinoids (10 mg/kg) was performed daily by orogastric gavage. Body composition was assessed by monitoring mass, fat and body adiposity index. Vascular morphology was determined by analyzing remodeling and vascular collagen deposition. Vascular reactivity was analyzed in the aorta by pharmacological assays involving the analysis of eNOS bioavailability, production of reactive oxygen species, participation of NADPH oxidase, AT1 receptors and the COX pathway. The results show that obesity increased body mass and adiposity index, however, chronic administration of capsinoids was not able to restore these parameters. Considering the glycemic and lipid profiles, obesity altered glycemia and total cholesterol, however treatment with capsinoids was also not able to restore these changes. The results also indicate that no changes were observed in plasma biomarkers of oxidative stress. In the vascular context, obesity increased reactivity through an increase in reactive oxygen species, especially superoxide anion, activation of AT1 receptors and release of contractile prostanoids via COX. Treatment with capsinoids reduced obesity-induced vascular reactivity through the participation of eNOS, in addition to reducing superoxide anion and COX-derived prostanoids. It was also able to increase the medial layer of vascular smooth muscle and reduce collagen deposition, preventing obesity-induced pathological remodeling. In conclusion, chronic administration of capsinoids at a dose of 10 mg/kg restores vascular reactivity parameters in obesity through vasodilation via eNOS and reduction of oxidative stress. Furthermore, it also shows that the treatment was able to prevent the pathological vascular remodeling process caused by obesity
- ItemEfeitos da sobrecarga crônica de ferro sobre a estrutura e função de artéria coronária de ratos(Universidade Federal do Espírito Santo, 2023-09-29) Rodrigues, Sabrina Bertoli; Santos, Leonardo dos; https://orcid.org/0000-0002-4340-6364; http://lattes.cnpq.br/4132087001362623; https://orcid.org/0000-0003-1134-5349; http://lattes.cnpq.br/8927452634782526; Bissoli, Nazaré Souza; https://orcid.org/0000-0002-3456-2437; http://lattes.cnpq.br/8865368585732583; Santos, Paulo Caleb Júnior de Lima; http://lattes.cnpq.br/7270343730265469; Furieri, Lorena Barros; https://orcid.org/0000000338592227; http://lattes.cnpq.br/0526203649991750; Rossoni, Luciana VenturiniIron is an essential mineral for several cellular processes, mainly due toitsabilitytoparticipate in reactions in which it receives or donates electrons. For thesamereason, when free and in excess, it is a great precursor in the generationof reactiveoxygen species, damaging tissues, organs and systems. Several studiesdemonstrate that iron overload is capable of causing cardiovascular damage, andaprobable relationship between the level of body iron and coronary artery diseasehaseven been suggested. In this study, we aimed to test the hypothesis that chronicironoverload, per se, causes damage to the coronary vasculature, associatedwiththegenerated oxidative stress and endothelial dysfunction. Serum, tissues andcoronaryvessels of male Wistar rats from the Ct and Fe groups were analyzed, inwhichsalinesolution (NaCl 0.9%) or iron-dextran (200 mg/kg/day) were administeredintraperitoneally, respectively, 5 times a week for 28 days. After euthanasia, bloodand organs were collected to assess serum and tissue iron, and vasoreactivity,fluorescence for reactive oxygen species and nitric oxide, histolomorphometrywereperformed in isolated coronary arteries. Finally, the modified Langedorff techniquetoassess the coronary bed was performed in a new set of experimental rats. Asexpected, iron overload increased serum and tissue iron levels, as well asreducedthe weight gain of animals in the Fe group compared to the Ct group. Furthermore,there was an increase in reactivity and a reduction in the vasodilator responseintheisolated rings of coronary arteries in the Fe group, associated with an increaseinthegeneration of superoxide anion, probably mediated by the AT1 receptor. Ironoverloadalso significantly reduced the bioavailability of nitric oxide in the coronary arteries. Inaddition to functional alterations, remodeling of arteries in the irongroupwasobserved, with collagen deposits and the presence of perivascular macrophages;together with this, alteration of the vascular endothelium with cell detachment wasevidenced, which suggests a denudation of this layer. In the analysis of theisolatedcoronary vascular bed, an increase in coronary perfusion pressure was observedinthis same Fe group, probably as a consequence of the increaseinvascularresistance and vasculopathy from iron overload. Our results demonstratethat chroniciron overload induces coronary endothelial dysfunction, probably duetooxidativestress and the imbalance between relaxing and contractile factors synthesizedbythedamaged endothelium.
- ItemO antioxidante mitocondrial, mitoquinona, previne a disfunção cardíaca 7 dias após infarto do miocárdio em rato(Universidade Federal do Espírito Santo, 2023-08-08) Ximenes, Carolina Falcão; Stefanon, Ivanita; https://orcid.org/0000-0003-2638-5183; http://lattes.cnpq.br/8456612999765726; https://orcid.org/0000-0001-6619-2285; http://lattes.cnpq.br/3613329548109549; Bissoli, Nazaré Souza; https://orcid.org/0000-0002-3456-2437; http://lattes.cnpq.br/8865368585732583; Baldo, Thaís de Oliveira Faria; https://orcid.org/0000-0001-8391-6177; http://lattes.cnpq.br/2809630268648026; Fonseca, Silvia Carolina Guatimosim; https://orcid.org/0000-0001-8386-3722; http://lattes.cnpq.br/7958786029463633Myocardial Infarction (AMI) is considered the main cause of heart failure (HF). It is believed that oxidative stress (ROS) plays a crucial role in the myocardium adjacent to the infarcted area and in the progression of left ventricular remodeling. At 7 days post-AMI, the decrease in myocardial contractility is associated with changes in the pathway of calcium (Ca2+) and ROS. However, the impact of mitochondrial ROS as a source of controlled dysfunction during the early phase of AMI will remains unknown. We hypothesize that MitoQ mitochondrial antioxidant treatment for 7 days after AMI will improve contractile function dependent on the reduction in mitochondrial ROS production in the acute phase of AIM. Therefore, our objective was to analyze the effect of treatment, for 7 days, with the specific mitochondrial antioxidant, MitoQ, on contractile dysfunction in the acute phase after AMI in rats. Wistar rats aged 12 weeks were divided into Sham, Infarto, Sham MitoQ and Infarto MitoQ (CEUA 16/2021). At the end of treatment with MitoQ for 7 days in drinking water (100 µM), analyzes of myocardial contractility “in vivo” were performed in hemodynamic parameters and “in vitro” measured in isolated papillary left ventricle (LV) with muscle length in which the active voltage is maximum (Lmáx); in presence of different extracellular concentrations of MitoQ; Ca2+ and isoproterenol. Cardiomyocytes isolated from the LV were used to measure morphological and temporal parameters of contractile function and transient Ca2+. Superoxide anion (O2 •- ) production was quantified using Dihydroethidium (DHE) and mitochondrial O2 •- using MitoSox Red. Statistical analysis used ANOVA two-way and post-hoc de Tukey’s and test t student, for p<0,05. Treatment with MitoQ did not change the area of infarction, However, it prevented the decrease in body weight gain and prevented the hemodynamic changes observed in the infarction group in the following parameters: systolic blood pressure (SBP) Sham: 113 ± 3; Infarto: 93 ± 4; Sham MitoQ: 108 ± 4; Infarto MitoQ: 108 ± 3*, mmHg *p<0.05); diastolic blood pressure (DBP) (Sham: 84 ± 3; Infarto: 68 ± 3; Sham MitoQ: 81 ± 3; Infarto MitoQ: 108 ± 3*, mmHg*p<0.05); left ventricular systole pressure (LVSP) (Sham: 116 ± 4.5; Infarto: 79 ± 2.7; Sham MitoQ: 115.8 ± 6; Infarto MitoQ: 100 ± 4.4*, mmHg *p<0.05); left ventricular end-diastolic pressure (LVDP) (Sham: 5 ± 0.4; Infarto: 10 ± 1; Sham MitoQ: 3 ± 1; Infarto MitoQ: 5 ± 0.5*, mmHg *p<0.05); first derivate of maximum pressure (dP/dtmáx) (Sham: 3993 ± 199; Infarto: 2480 ± 58; Sham MitoQ: 3326 ± 265; Infarto MitoQ: 2738 ± 103*, mmHg/s *p<0.05) and first derivate of minimum (dP/dtmin) (Sham: -3273 ± 227; Infarto: -1486 ± 41; Sham MitoQ: -2703 ± 88; Infarto MitoQ: -2083 ± 88*, mmHg/s *p<0,05). Treatment with MitoQ (100 uM) for 7 days was able to prevent the reduction of the isometric force of contraction of the animals in the infarction group (Sham: 0.56 ± 0.06; Infarto: 0.29 ± 0.05; Sham MitoQ: 0.47 ± 0.07; Infarto MitoQ: 0.73 ± 0.08* g/mg, *p<0.05), the reduction of the maximum positive derivative of force (+dF/dtmáx) (Sham: 25 ± 2.18; Infarto: 14.43 ± 2.20; Sham MitoQ: 16.88 ± 2.16; Infarto MitoQ: 24.17 ± 1.75 g/g/s, *p<0.05) and reduced contractility to extracellular Ca2+ influx (1,25 mM – Sham: 444 ± 49.86; Infarto: 229.83 ± 68.28; Sham MitoQ: 357.38 ± 29.97; Infarto MitoQ: 640.17 ± 60.9* g/g, *p<0.05). Morphometric analyses observed that treatment with MitoQ prevented the increase in cell area (Sham: 3846 ± 105; Infarto: 4309 ± 107; Sham MitoQ: 4107 ± 134; Infarto MitoQ: 3782 ± 116* µm2 , *p<0.05) and increased cell length (Sham: 141 ± 2.8; Infarto: 153 ± 1.95; Sham MitoQ: 144 ± 2.25; Infarto MitoQ: 137 ± 2.25* µm, *p<0,05) of cardiomyocytes in the initial stage of AMI. The cardiomyocytes contractility was increased in the Infarto group, which were prevented by MitoQ treatment such as cardiomyocyte shortening (Sham: 610 ± 26; Infarto: 815 ± 30; Sham MitoQ: 653,5 ± 25; Infarto MitoQ: 553,6 ± 30* µm2 , *p<0.05). MitoQ treatment prevented the increase in [Ca2+]i transient amplitude (Sham: 2.58 ± 0.04; Infarto: 3.15 ± 0.07; Sham MitoQ: 2.65 ± 0.08; Infarto MitoQ: 2.30 ± 0.05* F/F0, *p<0.05). The in-situ production of O2 •- , demonstrated by fluorescence intensity, was higher in the Infarto group, but treatment with MitoQ for 7 days prevented this increase in ROS. Mitochondrial O2 •- formation in isolated cardiomyocytes was greater in the Infarto group compared to the Sham group (p<0.01), and MitoQ treatment restored redox homeostasis. Our results demonstrated that MitoQ treatment prevented contractile dysfunction, confirming the involvement of mitochondrial ROS participation in the development of HF after AMI. In this way, find the most effective and safe way to modulate mitochondrial function and dynamics in HF after AMI in its initial phase represents a potential therapeutic target and an important step for the future of research in the treatment of cardiovascular diseases.
- ItemUso da espectroscopia FT-IR ATR e métodos de quimiometria em biofluidos para diagnósticos clínicos: efeito da diluição da amostra no diagnóstico da doença de Fabry(Universidade Federal do Espírito Santo, 2023-05-30) Leal, Leonardo Barbosa; Barauna, Valerio Garrone; https://orcid.org/0000000328320922; http://lattes.cnpq.br/1583882564447423; https://orcid.org/0000-0003-0968-4202; http://lattes.cnpq.br/1630453093149668; Graeff, Carlos Frederico de Oliveira; https://orcid.org/0000-0003-0162-8273; http://lattes.cnpq.br/5268607684223281; Mill, Jose Geraldo; https://orcid.org/000000020987368X; http://lattes.cnpq.br/2497419234600362; Teixeira, Carlos Graeff; https://orcid.org/0000000327250061; http://lattes.cnpq.br/0464152494769261; Valderrama, Patricia; Lima, Kassio Michell Gomes deFourier Transform Infrared Spectroscopy (ATR-FTIR) emerges as a powerful tool to aid the area of clinical medicine. The FTIR technique provides accurate, real-time results for clinical/diagnostic screening tests. This study aimed to study the effect of plasma sample dilution on Fabry disease classification. Fabry disease (FD), a rare X cromossome disorder with alpha-galactosidase A (α-GAL-A) deficiency. The equipment used was the Agilent Cary 630 spectrometer, equipped with a diamond crystal, Total Attenuated Reflection (ATR) system. The range between 400 to 4000 cm-1 was analyzed with a resolution of 4cm-1 with 32 raster and background scans. Analyzes of volume, drying time and dilution were carried out. Once the best dilution point was located, plasma samples from patients with SCD were analyzed in their total and diluted form. Average spectra in triplicates were obtained and analyzed in separate regions, FG fingerprint (800-1800cm-1 ) and high HW wavenumber (2800-4000cm-1 ) and pre-processed by line vector normalization. Unsupervised analyzes were performed, such as principal component analysis (PCA) and Unsupervised Random Forest (URF) and classification analysis such as GA-LDA along with Monte Carlo Method with 500 models, Support Vector Machine (SVM), K-near Neighbor (KNN) and PLS-DA (Partial Least Squres – Discriminated Analysis) were used to obtain the results. The results suggested that the ideal drying time for plasma analysis is from 18 minutes and a volume of 10µl. For dilution, the best result was 25%. Both models built with diluted and undiluted samples were able to identify patients with SCD with specificity and sensitivity above 80%. Models built with undiluted samples were able to generate the best predictive model for PD. However, it is still necessary to investigate the effect of dilution in the making of predictive models created from other biological samples, such as, for example, urine.
- ItemEfeitos da testosterona sobre a reatividade vascular de ratos hipertensos(Universidade Federal do Espírito Santo, 2023-02-15) Gonçalves, Leticia Tinoco; Santos, Roger Lyrio dos; https://orcid.org/0000-0003-3399-3523; http://lattes.cnpq.br/1122196233280741; https://orcid.org/0000-0003-2202-8541; http://lattes.cnpq.br/0836713525136907; Ceravolo, Graziela Scalianti; https://orcid.org/0000-0001-7558-6294; http://lattes.cnpq.br/0517142252318597; Padilha, Alessandra Simao; https://orcid.org/0000-0002-9585-1347; http://lattes.cnpq.br/7658998034219799; Bonaventura, Daniella; https://orcid.org/0000-0001-5253-4918; http://lattes.cnpq.br/9290907947235226; Santos, Leonardo dos; http://lattes.cnpq.br/4132087001362623The abusive use of testosterone is considered a global public health problem, with several side effects. In the cardiovascular system, its effects are still controversial, ranging from protective to deleterious actions. Because testosterone is a hormone that can be converted to 17 β-estradiol and dihydrotestosterone (DHT), part of the effects found with supraphysiological doses can be attributed to its metabolites. Therefore, we investigated the hypothesis that a supraphysiological dose of testosterone impairs the endothelium-dependent vasodilation of mesenteric resistance arteries, as well as its repercussions on oxidative stress (OS) and blood pressure (BP). We also evaluated the participation of 17 β-estradiol and DHT in the responses found. We used Spontaneously Hypertensive Rats (SHR), aged 8 to 10 weeks, divided into 5 groups: intact (SHAM), orchiectomized (ORX), intact testosterone-treated (TTO; 3 mg/Kg/day/s.c.), intact treated with testosterone and anastrozole [aromatase enzyme inhibitor (TTO+ANA; 0.1 mg/Kg/day)] and intact treated with testosterone and finasteride [5α-reductase enzyme inhibitor (TTO+FIN; 5 mg/Kg/day)] for 4 weeks. BP was assessed by tail cuff plethysmography. We performed concentration-response curves to acetylcholine (ACh, 0.1 nM - 10 µM) in mesenteric arteries using a wire myograph, in the absence and presence of pharmacological inhibitors. Also testosterone, 17 β-estradiol and dihydrotestosterone concentrations were evaluated. Vascular detection of superoxide anion (O2 •- ) and endothelium ultrastructure were analyzed by DHE and scanning electron microscopy (SEM), respectively. Data were expressed as mean ± standard error of the mean, and analyzed by Student's t-test or one-way or two-way ANOVA, followed by Tukey's post hoc test (p < 0.05). Orchiectomy reduced levels of testosterone, 17 β-estradiol and dihydrotestosterone, impaired ACh vasodilation, increased OS, altered endothelial morphology without altering BP. Testosterone treatment did not impair ACh vasodilation compared to the SHAM group, however it altered the endothelial pathways of relaxation, with lesser participation of NO and greater participation of prostanoids, possibly derived from COX-1. In addition, in the TTO group, the participation of EDH was greater compared to SHAM, indicating that EETs, H2O2 and K+ channels contributed to this vasodilator response. In the TTO+ANA group, the reduction in 17 β-estradiol levels did not impair ACh vasodilation, however, it decreased the participation of nitric oxide, prostanoids and increased EDH, and increased O2•- levels with alteration of endothelial morphology. TTO+FIN showed impairment in the vasodilator response to ACh, with an increased participation of NO and a lower participation of prostanoids. Regarding EDH, with a decrease in dihydrotestosterone, there was no increase in the participation of EETs, H2O2 and K+ channels compared to TTO. DHT seems to contribute to the decrease of NO and estrogen seems to stimulate the action of the NO pathway and prostanoids. In estrogen reduction, testosterone maintains endothelial vasodilation by greater stimulation of EDH, with more action of EETs, H2O2 and K+ channels, with greater formation of O2 •- . These results may contribute to the elucidation of the modulating role of testosterone on endothelial function, even in treatment with a supraphysiological dose, in addition to showing the importance of the presence of estrogen for the cardiovascular system in situations of endothelial dysfunction.