AMANDA APARECIDA RIBEIRO
Projetos de Pesquisa
Unidades Organizacionais
5 resultados
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- Pyridostigmine Bromide: Autonomic Nervous System Modulation Reduces Adipose and Splenic Tissue Weight in Leptin-Deficienty Ob/Ob Mice(2020) RIBEIRO, Amanda; SANTOS, Fernando dos; ARNOLD, Alexandre; BARBOSA, Maikon; JENSEN, Leonardo; IRIGOYEN, Maria Costa
- Aerobic Training Is Better Than Resistance Training on Cardiac Function and Autonomic Modulation in Female ob/ob Mice(2019) CONTI, Filipe Fernandes; IRIGOYEN, Maria-Claudia; SARTORI, Michelle; RIBEIRO, Amanda Aparecida; SANTOS, Fernando dos; MACHI, Jacqueline Freire; FIGUEROA, Diego Mendrot Taboas; RODRIGUES, Bruno; ANGELIS, Katia DeObjective: This study evaluated the effects of aerobic, resistance, and combined exercise training on cardiac function and autonomic modulation in female ob/ob mice. Methods: Four-week-old female wild type and obese (ob/ob) mice were divided into five groups (n = 8): control (WT), obese (OB) obese + aerobic training (OBA), obese + resistance training (OBR), and obese + combined training (OBC). The exercise training was performed on treadmill and/or ladder at 40-60% maximum test during 8 weeks. Cardiac function was measured using echo machine. Heart rate variability (HRV) was evaluated in the time and frequency domain. Results: OB group presented higher body weight gain (similar to 600%), glycemia (similar to 44%) and glucose intolerance (similar to 150%), reduction of cardiac vagal modulation, evidenced by a lower RMMSD (similar to 56%), total power and high frequency band, and a higher isovolumic relaxation time (IVRT) (similar to 24%) in relation to the WT group. Aerobic and combined training led to a lower IVRT (OBA: similar to 14%; OBC: similar to 14%) and myocardial global index (OBA: similar to 37%; OBC: similar to 44%). The OBA group presented an increased in vagal indexes of HRV than the other ob/ob groups. A negative correlation was observed between the delta of aerobic exercise capacity and MPI (r = 0.45; p = 0.002) and exercise capacity and body weight gain (r = 0.39; p = 0.002). Conclusion: Only the obese females underwent to aerobic exercise training showed improvement in cardiac function and HRV. Moreover, the aerobic exercise capacity as well as a greater responsivity to aerobic exercise training is intimately associated with these improvements, reinforcing the importance of aerobic exercise training to this population.
- THE EFFECTS OF PYRIDOSTIGMINE BROMIDE ON AUTONOMIC, HEMODYNAMIC AND METABOLIC PARAMETERS IN FEMALE OVARIECTOMIZED C57BL/6 MICE(2018) RIBEIRO, Amanda; SILVA, Maikon; ARNOLD, Alexandre Jose; JENSEN, Leonardo; SANTOS, Fernando; IRIGOYEN, Maria-Claudia
- 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.
- Nicotinamide attenuates streptozotocin-induced diabetes complications and increases survival rate in rats: role of autonomic nervous system(2021) CRUZ, Paula L.; MORAES-SILVA, Ivana C.; RIBEIRO, Amanda A.; MACHI, Jacqueline F.; MELO, Marcelo Dantas Tavares de; SANTOS, Fernando dos; SILVA, Maikon Barbosa da; STRUNZ, Celia Maria Cassaro; CALDINI, Elia Garcia; IRIGOYEN, Maria-ClaudiaBackground To evaluate the effect of nicotinamide prior to streptozotocin-induced (STZ) diabetes in baroreflex sensitivity and cardiovascular autonomic modulation, and its association with hemodynamics and metabolic parameters. Methods Methods: Male Wistar rats were divided into control (Cont) and STZ-induced diabetes (Diab). Half of the rats from each group received a single dose of nicotinamide (100 mg/Kg) before STZ injection (Cont+NicA and Diab+NicA). All groups were followed-up for 5 weeks. Results Body weight loss of more than 40% was observed in Diab throughout the period (Diab: 271.00 +/- 12.74 g; Diab+NicA: 344.62 +/- 17.82). Increased glycemia was seen in Diab rats (541.28 +/- 18.68 mg/dl) while Diab+NicA group had a slight decrease (440.87 +/- 20.96 mg/dl). However, insulin resistance was observed only in Diab. In relation to Cont, heart rate, mean blood pressure and diastolic function were reduced when compared to Diab, together with parasympathetic modulation and baroreflex sensitivity. All of these parameters were improved in Diab+NicA when compared to Diab. Improved baroreflex sensitivity and parasympathetic modulation were correlated with glycemia, insulin resistance, and body weight mass. Additionally, Diab+NicA group increased survival rate. Conclusions Results suggest that the association of nicotinamide in STZ-induced diabetic rats prevents most of the expected derangements mainly by preserving parasympathetic and baroreflex parameters.