DEFAR - Artigos publicados em periódicos
URI permanente para esta coleçãohttp://www.hml.repositorio.ufop.br/handle/123456789/531
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Item Spironolactone and eplerenone are cardioprotective during early phase of ischemia in rats submitted to acute coronary occlusion.(2022) Amancio, Gabriela de Cássia Sousa; Hermidorff, Milla Marques; Alvarenga, Ana Cláudia; Lima, Wanderson Geraldo de; Guimarães, Homero Nogueira; Rodrigues, Henrique Resende; Silva, Emília Calil; Assis, Leonardo Vinícius Monteiro de; Guimarães, Andrea Grabe; Isoldi, Mauro CésarIntroduction: Mineralocorticoid receptor antagonists (MRAs) are effective in reducing left ventricle remodeling and sudden death after acute myocardial infarction (AMI). Objectives: MRAs in vitro display cardioprotective effects, independent of MR; however, it is unknown whether the rapid effects of MRAs are cardioprotective in vivo. This study evaluated the acute effects of spironolactone and eplerenone in the first minutes of AMI. Methods: Wistar Rats, submitted or not to bilateral adrenalectomy, were treated orally with spironolactone (20 mg/kg) or eplerenone (10 mg/kg), and submitted to the left coronary ligation, under anesthesia. Electrocardiogram (ECG) recordings were obtained to evaluate ST-T segment, QT, and QTc intervals. Arterial pressure was also measured before (baseline) and after coronary ligation. Results: Spironolactone or eplerenone given, one hour before coronary ligation, prevented ST- T segment elevation in adrenalectomized and non-adrenalectomized. QT interval analysis showed that MRAs prevented its prolongation after coronary ligation. QT and QTc intervals remained similar to baseline and were smaller than the values displayed by the non-treated group. Animals treated with spironolactone, regardless of adrenalectomy, showed a 3-fold reduced mortality rates compared to the control group. Conclusion: MRAs display acute cardioprotective effects in early phase of AMI, which are independent of aldosterone.Item Toxicological study of a new doxorubicin-loaded pH-sensitive liposome : a preclinical approach.(2018) Silva, Juliana de Oliveira; Miranda, Sued Eustaquio Mendes; Leite, Elaine Amaral; Sabino, Adriano de Paula; Borges, Karina Braga Gomes; Cardoso, Valbert Nascimento; Cassali, Geovanni Dantas; Guimarães, Andrea Grabe; Oliveira, Mônica Cristina de; Barros, André Luís Branco deDoxorubicin (DOX) is widely used in cancer treatment, however, the use of this drug is often limited due to its cardiotoxic side effects. In order to avoid these adverse effects, the encapsulation of DOX into nanosystems has been used in the last decades. In this context, pH-sensitive liposomes have been shown promising for delivering cytotoxic agents into tumor cells, however, the lack of information about in vivo toxicity of this nanocarrier has impaired translational studies. Therefore, the aim of this work was to investigate the acute toxicity and cardiotoxicity of DOX-loading pH-sensitive liposomes (SpHL-DOX). To achieve this, female BALB/c mice, after intravenous administration, were monitored by means of clinical, laboratory, histopathological and electrocardiographic (ECG) analyses. Results indicate that SpHL was able to prevent renal toxicity and the hepatic injury was less extensive than free DOX. In addition, lower body weight loss was associated with less ECG QT interval prolongation to animals receiving SpHL-DOX (14.6 ± 5.2%) compared to animals receiving free DOX (35.7 ± 4.0%) or non-pH-sensitive liposomes (nSpHL-DOX) (47.0 ± 9.8%). These results corroborate with SpHL-DOX biodistribution studies published by our group. In conclusion, the SpHL-DOX showed less toxic effects on mice compared to free DOX or nSpHL-DOX indicating that SpHL-DOX is a promising strategy to reduce the serious cardiotoxic effects of DOX.Item Reduced cardiotoxicity and increased oral efficacy of artemether polymeric nanocapsules in Plasmodium berghei-infected mice.(2018) Souza, Ana Carolina Moreira; Mosqueira, Vanessa Carla Furtado; Silveira, Ana Paula Amariz; Antunes, Lidiane Rodrigues; Richard, Sylvain; Guimarães, Homero Nogueira; Guimarães, Andrea GrabeArtemether (ATM) cardiotoxicity, its short half-life and low oral bioavailability are the major limiting factors for its use to treat malaria. The purposes of this work were to study free-ATM and ATM-loaded poly-ε-caprolactone nanocapules (ATM-NC) cardiotoxicity and oral efficacy on Plasmodium berghei-infected mice. ATM-NC was obtained by interfacial polymer deposition and ATM was associated with polymeric NC oily core. For cardiotoxicity evaluation, male black C57BL6 uninfected or P. berghei-infected mice received, by oral route twice daily/4 days, vehicle (sorbitol/carboxymethylcellulose), blank-NC, free-ATM or ATMNC at doses 40, 80 or 120 mg kg−1 . Electrocardiogram (ECG) lead II signal was obtained before and after treatment. For ATM efficacy evaluation, female P. berghei-infected mice were treated the same way. ATM-NC improved antimalarial in vivo efficacy and reduced mice mortality. Free-ATM induced significantly QT and QTc intervals prolongation. ATMNC (120 mg kg−1 ) given to uninfected mice reduced QT and QTc intervals prolongation 34 and 30%, respectively, compared with free-ATM. ATM-NC given to infected mice also reduced QT and QTc intervals prolongation, 28 and 27%, respectively. For the first time, the study showed a nanocarrier reducing cardiotoxicity of ATM given by oral route and it was more effective against P. berghei than free-ATM as monotherapy.Item Prolonged cardioprotective effect of pyridostigmine encapsulated in liposomes.(2010) Vidal, Alessandra Teixeira; Guimarães, Homero Nogueira; Paula, Danielle Cristiane Correa de; Frezard, Frederic Jean Georges; Barcellos, Neila Marcia Silva; Guimarães, Andrea GrabeAims: The purpose of the present work was to investigate the ability of pyridostigmine encapsulated in longcirculating liposomes, to protect against ECG(electrocardiogram) alterations induced by sympathetic stimulation in rats. Main methods: The encapsulation of pyridostigmine was carried out by freeze–thaw and extrusion. Blood pressure and ECG (limb lead II) were monitored in anaesthetized male Wistar rats. The formulation containing pyridostigmine was intravenously administrated in 0.1, 0.3 and 1.0 mg/kg doses, and sympathetic stimulation was conducted by administration of 1 or 3 μg of noradrenaline (NA) after 1, 2, 4 or 6 h. The obtained cardiovascular parameters were compared to animals that received intravenous injection of pyridostigmine in free form or saline. Key findings: After saline, NA induced a significant increase in QT interval (22.3% after 3.0 μg). Previous administration of free pyridostigmine significantly prevented the increase of QT interval after sympathetic stimulation and the most prominent effect was observed after 1h for the dose of 0.3 mg/kg (6.8% after 3.0 μg of NA) and was no longer observed after 2 h of the treatment. On the other hand, the maximum effect of pyridostigmine in liposomal formulation preventing QT interval increasewas observed 2 h after treatment (9.7% after 3.0 μg of NA) and was still present until 6 h when 1 mg/kg was previous administrated. Significance: The results of the present study, beyond to confirm the cardioprotective action of pyridostigmine, suggest that liposomal pyridostigmine may be a potential therapeutic alternative to prevent cardiovascular disturbances resulting from sympathetic hyperactivity.