LEANDRO EZIQUIEL DE SOUZA
Índice h a partir de 2011
7
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina
11 resultados
Resultados de Busca
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conferenceObject Effects of aerobic exercise training on obese female mice: metabolic and autonomic evaluation(2013) SARTORI, Michelle; SOUZA, Leandro Eziquiel de; SOUZA, Pamella Ramona de; SANTOS, Fernando; ANGELIS, Katia De; IRIGOYEN, Maria ClaudiaThe aim of this study was to evaluate the metabolic and autonomic parameters in trained youth obese mice. Female ob/ob mice (4 weeks old) were randomized into sedentary (OS, n=11) or trained (OT, n=8) (treadmill,5 days/w, 60 min/d, during 8 wks) groups. Blood glucose was measured by reagent strips. Blood pressure signals were recorded using a data acquisition system. The OT group had higher exercise capacity compared to the OS group. OT group had reduced body weight, white adipose tissue and blood glucose (45±2g, 6.1±1g and 133±3g mg/dL) compared to OS group (50±2g, 6.1±1g and 169±8 mg/dL). Exercise training improved glucose tolerance in trained group (OS: 27961±6501 vs. OT: 18258±6283 mg/dL/min). Mean arterial pressure and heart rate were similar between groups. The trained group showed increase in heart rate variability compared with sedentary group (OT: 50±12 vs. OS: 33±8ms2). Blood pressure variability and low frequency band were higher in OS group (23 ± 3mmHg2 and 7 ± 1 mmHg2) compared to OT (15 ± 2 mmHg2 and 5 ± 1 mmHg2). Moreover, the spontaneous baroreflex sensitivity, represented by alpha index, was lower in sedentary group (1.2 ± 0.3 ms/mmHg) compared to trained group (1.9 ± 0.2 ms/mmHg). In conclusion, our results suggest that physical training during lifespan can be effective inattenuating the increase in weight and blood glucose and improving blood pressure variability in obese mice.- Cardiovascular autonomic dysfunction in non-obese diabetic mice(2013) MORAES, Oscar A.; COLUCCI, Juliana A.; SOUZA, Leandro E.; SCAPINI, Katia B.; MORAES-SILVA, Ivana C.; MOSTARDA, Cristiano; ANGELIS, Katia De; CASARINI, Dulce E.; IRIGOYEN, Maria ClaudiaIt is known that diabetes is associated with autonomic dysfunction; however, data about autonomic function in non-obese diabetic mice (NOD) remain scarce. We evaluated the autonomic profile of NOD mice. Female mice, 24-28 week old, were divided in two groups: NOD (n = 6) and control (n = 6, Swiss mice). NOD mice with glycemia >= 300 mg/dl were used. Heart rate variability (HRV) and arterial pressure variability (APV) in time and frequency domains, symbolic analysis of heart rate (HR) and baroreflex sensitivity were evaluated. HR and arterial pressure (AP) were similar between the groups; however, HRV (total variance of RR interval: NOD = 21.07 +/- 3.75 vs. C = 42.02 +/- 6.54 ms(2)) and the vagal modulation index RMSSD were lower in NOD group (4.01 +/- 032 vs. 8.28 +/- 0.97 ms). Moreover, the absolute and normalized low-frequency (LF) components were also enhanced in NOD (normalized = 61.0 +/- 4.0%) as compared to control mice (normalized = 20.0 +/- 4.0%). Both the absolute and normalized high-frequency (HF) components were lower in NOD (normalized = 39.0 +/- 4.0%) when compared to the control group (normalized = 80.0 +/- 4.0). In the symbolic analysis the 0V pattern, an indication of sympathetic activity, was higher in NOD and 2LV pattern, an indication of parasympathetic activity, was lower in the NOD than in the control group. Both bradycardic and tachycardic responses were decreased in NOD (3.01 +/- 0.72 vs. 4.54 +/- 0.36 bpm/mm Hg and 2.49 +/- 031 vs. C = 3.43 +/- 033 bpm/mm Hg) when compared to the control group. Correlation analysis showed negative correlations between vagal indexes (RMSSD, %HF and 2LV) and glycemic levels. In conclusion, NOD mice develop severe diabetes correlated with autonomic dysfunction.
- Interval and continuous aerobic exercise training similarly increase cardiac function and autonomic modulation in infarcted mice (vol 13, pg 257, 2017)(2017) ABAD, Cesar Cavinato Cal; NASCIMENTO, Ademir Manuel do; SOUZA, Leandro Eziquiel de; FIGUEROA, Diego; RAMONA, Pamella; SARTORI, Michele; SCAPINI, Katia B.; ALBUQUERQUE, Oscar; MORAES-SILVA, Ivana Cinthya; COELHO-JUNIOR, Helio Jose; RODRIGUES, Bruno; MOSTARDA, Cristiano Teixeira; ANGELIS, Katia De; IRIGOYEN, Maria Claudia
conferenceObject Interval training program improves cardiac function and physical performance in heart failure mice(2013) ABAD, Cesar Cavinato Cal; MOSTARDA, Cristiano Teixeira; NASCIMENTO, Ademir Manuel; SANTOS, Mirailton Alves dos; SOUZA, Leandro Eziquiel; FIGUEROA, Diego M. T.; SANTOS, Fernando; SOUZA, Pamella Ramona Moraes de; ANGELIS, Katia De; IRIGOYEN, Maria ClaudiaThis study was designed to verify the effect of an eight week interval training program (IT) in systolic and diastolic functions and physical performance in heart failure mice (C57B16, n=24). The animals were divided in three groups: 1) Intact sedentary (C), 2) infarcted sedentary (MI-s); and 3) infarcted trained (MI-i). At the begining (M1) and at the end of IT (M2), time of maximal running performance (Tvmáx) was quantified. The ejection fraction (EF), shortening fraction (SF) and isovolumetric relaxation time (IVRT) were accessed by echocardiography in M2. At 60 days after coronary artery occlusion the IT was started (4min at 80% Vmáx x 4min at 40% Vmáx during 60min). The results are presented in mean and SEM. Myocardial infarction area was not different between groups in both evaluation time (M1vsM2). The EF and SF in MI-s were lower than C (44±3.7vs58±3.0% and 22±2vs31±2%, respectively; p≤0.05) but similar between MI-i and C (56±5vs58±3% and 25±3vs31±2%, respectively). The IVRT was higher (p≤0.05) in MI-s (25.6±4ms) than C (13±1ms) while similar in MI-i (15±0.8ms) and C. At the M1 both MI-s and MI-i Tvmáx decreased in comparison with C (620±16 and 644±28vs840±17s, respectively). At the M2, Tvmáx delta percent was higher in MI-i than MI-s (64±8vs15±6%, respectively; p≤0.05) and C (0.53±3%). The results suggest that IT improves cardiac function and physical performance in heart failure mice.- Tonin Overexpression in Mice Diminishes Sympathetic Autonomic Modulation and Alters Angiotensin Type 1 Receptor Response(2019) JARA, Zaira Palomino; ICIMOTO, Marcelo Yudi; YOKOTA, Rodrigo; RIBEIRO, Amanda Aparecida; SANTOS, Fernando dos; SOUZA, Leandro Ezequiel de; WATANABE, Ingrid Kazue Mizuno; FRANCO, Maria do Carmo; PESQUERO, Jorge Luiz; IRIGOYEN, Maria Claudia; CASARINI, Dulce ElenaBackground: Tonin, a serine-protease that forms Angiotensin II (AngII) from angiotensinogen, is increased in failing human heart samples. Increased blood pressure (BP) and decreased heart rate (HR) variabilities are associated with higher risk of cardiovascular morbidity. Losartan has been used to reduce hypertension and, therefore, lowers the risk of fatal and non-fatal cardiovascular events. Determination of tonin's impact on BP and HR variabilities as well as the impact of losartan remain questions to be elucidated. Aim: Evaluation of cardiovascular autonomic profile in transgenic mice overexpressing the rat tonin enzyme TGM'(rton) and the impact of AT1 receptor blocker, losartan. Methods: Male C57BL/6 (WT) and TGM'(rTon) mice were cannulated for recording BP (Windaq, 4 MHz) for 30min at baseline and 30min after losartan injection (20 mg/kg). BP and HR variabilities were analyzed in time and frequency domain method. Low-frequency (LF) and high-frequency (HF) components were identified for sympathetic and parasympathetic modulations analysis. Ang I, AngII, and Ang1-7 were quantified by high performance liquid chromatography method. The total enzymatic activity for AngI, AngII, and Ang1-7 formation was evaluated in the heart and plasma by Liquid chromatography mass spectrometry (LC-MS/MS). Results: At the baseline TGM'(rTon) exhibited higher BP, lower cardiac LF, higher cardiac HF, lower LF/HF, and lower alpha index than wild type (WT). After losartan injection, TGM'(rTon) mice presented an additional decrease in cardiac LF and increase in HF in relation to baseline and WT. In the vasculature, losartan caused decreased in BP and LF of systolic BP in WT mice in relation to its baseline. A similar effect was observed in the BP of TGM'(rTon) mice; however, LF of systolic BP increased compared to baseline. Our data also indicates that AT1R receptor signaling has been altered in TGM'(rTon) mice. Interestingly, the dynamics of the renin-angiotensin system kinetics change, favoring production of Ang1-7. Conclusion: Autonomic evaluation of TGM'(rTon) mice indicates an unclear prognosis for diseases that affect the heart. HR variability in TGM'(rTon) mice indicates high risk of morbidity, and sympathetic and parasympathetic modulation indicate low risk of morbidity. The low risk of morbidity could be the biased production of Ang1-7 in the heart and circulation; however, the altered response of AT1R in the TGM'(rTon) remains to be elucidated, as well aswhether that signaling is pro-protection or pro-pathology.
- Effects of sympathectomy on myocardium remodeling and function(2021) JORDAO, Mauricio Rodrigues; PESSOA, Fernanda G.; FONSECA, Keila C. B.; ZANONI, Fernando; SALEMI, Vera M. C.; SOUZA, Leandro E.; RIBEIRO, Orlando N.; FERNANDES, Fabio; IRIGOYEN, Maria Claudia; MOREIRA, Luiz Felipe P.; MADY, Charles; RAMIRES, Felix Jose AlvarezOBJECTIVES: To evaluate the effects of sympathectomy on the myocardium in an experimental model. METHODS: The study evaluated three groups of male Wistar rats: control (CT; n=15), left unilateral sympathectomy (UNI; n=15), and bilateral sympathectomy (BIL; n=31). Sympathectomy was performed by injection of absolute alcohol into the space of the spinous process of the C7 vertebra. After 6 weeks, we assessed the chronotropic properties at rest and stress, cardiovascular autonomic modulation, myocardial and peripheral catecholamines, and beta-adrenergic receptors in the myocardium. The treadmill test consisted of an escalated protocol with a velocity increment until the maximal velocity tolerated by the animal was reached. RESULTS: The bilateral group had higher levels of peripheral catecholamines, and consequently, a higher heart rate (HR) and blood pressure levels. This suggests that the activation of a compensatory pathway in this group may have deleterious effects. The BIL group had basal tachycardia immediately before the exercise test and increased tachycardia at peak exercise (p<0.01); the blood pressure had the same pattern (p=0.0365). The variables related to autonomic modulation were not significantly different between groups, with the exception of the high frequency (HF) variable, which showed significant differences in CT vs UNI. There was no significant difference in beta receptor expression between groups. There was a higher concentration of peripheral norepinephrine in the BIL group (p=0.0001), and no significant difference in myocardial norepinephrine (p=0.09). CONCLUSION: These findings suggest that an extra cardiac compensatory pathway increases the sympathetic tonus and maintains a higher HR and higher levels of peripheral catecholamines in the procedure groups. The increase in HF activity can be interpreted as an attempt to increase the parasympathetic tonus to balance the greater sympathetic activity.
conferenceObject CARDIORENAL DYSFUNCTION IN MICE SUBMITTED TO AORTIC STENOSIS AND TREATED WITH SODIUM OXALATE(2023) SILVA, Amanda; MARQUES, Juliana; NASCIMENTO, Bruno; SOUZA, Leandro; SILVA, Maikon; BENETTI, Acaris; IRIGOYEN, Maria Claudia- (Pro)renin receptor expression in myocardial infarction in transgenic mice expressing rat tonin(2018) RIBEIRO, Amanda A.; AMORIM, Rebeca Padrao; PALOMINO, Zaira J.; LIMA, Mercia de Paula; MORAES-SILVA, Ivana Cinthya; SOUZA, Leandro Ezequiel; PESQUERO, Jorge Luiz; IRIGOYEN, Maria Claudia; CASARINI, Dulce E.The (pro)renin receptor [(P)RR] has been implicated as a renin/prorenin receptor, and plays a role in local renin angiotensin system activation. Our goal was to investigate whether a transgenic mouse that expresses rat tonin [TGM'(rTon)] can regulate (P)RR mRNA levels. Control (C) and TGM'(rTon) animals were subdivided into the C sham, C MI, TGM'(rTon) sham, and TGM'(rTon) MI groups. The levels of tonin, (P)RR, and renin were determined using RT-PCR mRNA. Tonin activity as determined by RIE was significantly increased in the TGM'(rTon) sham group as compared to the C sham group in the atrium (AT) and right ventricle (RV), respectively. In most mice, tonin mRNA levels were significantly reduced compared to those in the TGM'(rTon) sham group in the atria. In this structure, the (P)RR mRNA levels were statistically significantly reduced in the TGM'(rTon) sham and TGM'(rTon) MI groups compared to the control groups. However, the (P)RR mRNA values were significantly increased when we compared the TGM'(rTon) MI vs TGM'(rTon) sham groups. In the RV, the renin mRNA levels in the TGM'(rTon) sham group were significantly reduced compared to the C sham group. Tonin overexpression may act in the regulation of (P)RR mRNA levels during MI.
conferenceObject Ventricular disfunction induces morphofunctional changes in adrenal glands(2016) ANDRADE, Thulio Ramos de; SILVA, Juliane; SOUZA, Leandro; JORDAO, Camila; FERRELRA, Tatiane; NEGRAO, Carlos; BRUM, Patricia; IRIGOYEN, Maria Claudia; LACCHINI, Silvia; ALVES, Maria JanieireconferenceObject Markers of acute cardiovascular inflammation induced by angiotensin II in a murine model(2013) SANTANA, Andre Bento Chaves; SOUZA-OLIVEIRA, Thais; BARAUNA, Valerio; SOUZA, Leandro; IRIGOYEN, Maria Claudia; CAMPOS, Luciene; KRIEGER, Jose Eduardo; LACCHINI, SilviaAngiotensin II has important physiological functions for the homeostasis of the cardiovascular system and may also induce to inflammatory responses. The aim of this study was to evaluate the effetc of subpressor angiotensin II (AngII) on expression of inflammatory markers in cardiac vessels. Were used C57Bl/6J male mice, treated with subpressor dose of AngII (30ng/kg IP), confirmed by carotid catheterization and arterial pressure measure after 10, 30, 60min, and 2 and 6hours of AngII injection (n=5/saline; n=5/AngII). Inflammatory markers were evaluated in cardiac vessels (TGF-beta, IL-6 and iNOS) by western blot, and localized in vessels by immunohistochemistry. Mice were evaluated after 1 and 24 hours to identify acute responses. Results were compared by ANOVA, using p≤0.05 as significant. Blood pressure measurements showed no changes in arterial pressure and heart rate. Protein analysis showed an increase of inflammatory markers in cardiac tissue after 1 hour TGF-beta (84%), IL-6 (90%) and iNOS (70%). However, these markers were unchanged after 24 hours. Immunohistochemistry analysis showed a specific increase in these markers associated to cardiac vessels. The results suggests that, independently on hemodynamic influences, Angiotensin II leads to expression of inflammatory markers in cardiac vessels in a short period, and this may represent a direct pro-inflammatory action mediated by angiotensin II.