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PURPOSE: Oxidative stress and apoptosis contribute to the pathological basis of doxorubicin (DOX)-induced cardiotoxicity. Columbianadin (CBN) is one of the main bioactive constituents isolated from the root of Angelica pubescens. Herein, we intended to explore the potential role and molecular basis of CBN in DOX-induced cardiotoxicity. METHODS: C57BL/6 mice were subjected to DOX (15 mg/kg/day, i.p.) to generate DOX-induced cardiotoxicity. CBN (10 mg/kg/day, i.p.) was administered for four week following DOX injection. RESULTS: DOX administered markedly dampened cardiac function, increased cardiac injury, excessive reactive oxygen species (ROS) production, and cardiomyocyte loss. These alterations induced by DOX significantly alleviated by CBN treatment. Mechanistically, our results demonstrated that the CBN exerts cardioprotection role against DOX by up-regulating silent information regulator 1 (Sirt1) and decreasing acetylation of forkhead box O1 (FOXO1). Moreover, Sirt1 inhibition with Ex-527 significantly blunt the beneficial effect of CBN on DOX-induced cardiotoxicity, including cardiac dysfunction, ROS, and apoptosis. CONCLUSION: Collectively, CBN attenuated oxidative stress and cardiomyocyte apoptosis in DOX-induced cardiotoxicity through maintaining Sirt1/FOXO1 signaling pathway. Our results demonstrated that CBN might be used to treat DOX-related cardiotoxicity.

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Pyrethroids (PY) are synthetic pesticides used in many applications ranging from large-scale agriculture to household maintenance. Their classical mechanisms of action are associated with binding to the sodium channel of insect neurons, disrupting its inactivation, ensuring their use as insecticides. However, PY can also lead to toxicity in vertebrates, including humans. In most toxicological studies, the impact of PY on heart function is neglected. Acute exposure to a high dose of PY causes enhancement of the late sodium current (INaL), which impairs the action potential waveform and can cause severe cardiac arrhythmias. Moreover, long-term, low-dose exposure to PY displays oxidative stress in the heart, which could induce tissue remodeling and impairment. Isolated and preliminary evidence supports that, for acute exposure to PY, an antiarrhythmic therapy with ranolazine (an INaL blocker), can be a promising therapeutic approach. Besides, heart tissue remodeling associated with low doses and long-term exposure to PY seems to benefit from antioxidant therapy. Despite significant leaps in understanding the mechanical details of PY intoxication, currently, few studies are focusing on the heart. In this review, we present what is known and what are the gaps in the field of cardiotoxicity induced by PY.

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Balancing safety and efficacy is a major consideration for cancer treatments, especially when combining cancer immunotherapy with other treatment modalities such as chemotherapy. Approaches that induce immunogenic cell death (ICD) are expected to eliminate cancer cells by direct cell killing as well as activation of an antitumor immune response. We have developed a gene therapy approach based on p19Arf and interferon-ß gene transfer that, similar to conventional inducers of ICD, results in the release of DAMPS and immune activation. Here, aiming to potentiate this response, we explore whether association between our approach and treatment with doxorubicin (Dox), a known inducer of ICD, could further potentiate treatment efficacy without inducing cardiotoxicity, a critical side effect of Dox. Using central composite rotational design analysis, we show that cooperation between gene transfer and chemotherapy killed MCA205 and B16F10 cells and permitted the application of reduced viral and drug doses. The treatments also cooperated to induce elevated levels of ICD markers in MCA205, which correlated with improved efficacy of immunotherapy in vivo. Treatment of subcutaneous MCA205 tumors associating gene transfer and low dose (10 mg/kg) chemotherapy resulted in inhibition of tumor progression. Moreover, the reduced dose did not cause cardiotoxicity as compared to the therapeutic dose of Dox (20 mg/kg). The association of p19Arf/interferon-ß gene transfer and Dox chemotherapy potentiated antitumor response and minimized cardiotoxicity.

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Although liposomal doxorubicin (LPD) is widely used for cancer treatment, knowledge concerning the toxicity induced by this drug in healthy organs and tissues is limited. LPD-induced toxicity studies relative to free doxorubicin (DOX) have focused on cardiotoxicity in tumor-bearing animals. On the other hand, the results on DOX-induced cardiotoxicity depending on gender are controversial. One of the manifestations of toxicity is tissue inflammation. 67Ga-citrate has been used for decades to assess inflammation in various pathologies. In this work, the ex vivo biodistribution of 67Ga-citrate is used to evaluate induced multi-organ toxicity in healthy 10-week-old male and female CD1 mice treated for 5 weeks with LPD. Toxicity in males, determined by 67Ga-citrate, was evident only in the target organs of liposomes (spleen, liver, kidneys, and lungs); the average weight loss was 11% and mortality was 14%. In female mice, 67Ga-citrate revealed a cytotoxic effect in practically all organs, the average weight loss was 37%, and the mortality after the last dose of LPD was 66%. These results confirm the usefulness of 67Ga-citrate and the importance of stratifying by sex in the toxicological evaluation of drugs.

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Abstract Background Various studies are ongoing related to the radioprotective agents. Herbal preparations are currently becoming popular because of their beneficial effects with fewer side effects compared to the synthetic/semi-synthetic medicines, and Nigella sativa oil (NSO) is only one of them. Objective To investigate NSO for its antioxidant effects on the heart tissue of rats exposed to ionizing radiation (IR). Methods Thirty six male albino Wistar rats, divided into four groups, were designated to group I (IR plus NSO group) that received both 5 Gray of gamma IR to total cranium and NSO; group II (IR alone group) that received IR plus saline, group III (control group of NSO) that received saline and did not receive NSO or IR; group IV (control group) that received only sham IR. Alterations in Total antioxidant status (TAS) and Total oxidant status (TOS), Oxidative stres index (OSI), Sulhydryl group (SH), Lipid hydroperoxide (LOOH), Paraoxonase (PON) levels, Arylesterase (ARE) and Ceruloplasmin (CER) activities in homogenized heart tissue of rats were measured by biochemical methods. Results In heart tissue of the rats in the IR alone group (group II) LOOH, TOS and OSI levels were found to be higher, ARE activity and TAS level were found to be lower than all of the other groups (p < 0.01). These results also support that IR increases oxidative stress and NSO's protective effect. Conclusion NSO would reduce the oxidative damage in the irradiated heart tissue in the experimental rat model.

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ß-Cyfluthrin, a class II Pyrethroid, is an insecticide used worldwide in agriculture, horticulture (field and protected crops), viticulture, and domestic applications. ß-Cyfluthrin may impair the function of biological systems; however, little information is available about its potential cardiotoxic effect. Here, we explored the acute toxicity of ß-Cyfluthrin in isolated heart preparations and its cellular basis, using isolated cardiomyocytes. Moreover, ß-Cyfluthrin effects on the sodium current, especially late sodium current (INa-L), were investigated using human embryonic kidney cells (HEK-293) cells transiently expressing human NaV1.5 channels. We report that ß-Cyfluthrin raised INa-L in a dose-dependent manner. ß-Cyfluthrin prolonged the repolarization of the action potential (AP) and triggered oscillations on its duration. Cardiomyocytes contraction and calcium dynamics were disrupted by the pesticide with a marked incidence of non-electronic-stimulated contractions. The antiarrhythmic drug Ranolazine was able to reverse most of the phenotypes observed in isolated cells. Lastly, ventricular premature beats (VPBs) and long QT intervals were found during ß-Cyfluthrin exposure, and Ranolazine was able to attenuate them. Overall, we demonstrated that ß-Cyfluthrin can cause significant cardiac alterations and Ranolazine ameliorated the phenotype. Understanding the insecticides' impacts upon electromechanical properties of the heart is important for the development of therapeutic approaches to treat cases of pesticides intoxication.

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Purpose: The present study explored the role of melatonin in cisplatin-induced cardiac injury along with the possible role of brain-derived neurotrophic factor (BDNF) in melatonin-mediated effects. Methods: Wistar rats were administered cisplatin (10 mg/kg), and cardiac injury was assessed by measuring the levels of cardiac troponin (cTnT) and lactate dehydrogenase (LDH-1).The extent of apoptosis was measured by measuring caspase-3 (pro-apoptotic) and Bcl-2 (anti-apoptotic) in hearts. The levels of BDNF, tumour necrosis factor α (TNF-α) and reduced glutathione were measured in heart. Melatonin (5 and 10 mg/kg) was administered for 15 days, and the role of BDNF was identified by co-administering BDNF inhibitor, ANA-12 (0.25 and 0.5 mg/kg). Results: Melatonin attenuated cTnT and LDH-1 levels along with reduction in caspase-3 and increase in Bcl-2. It also increased cisplatin-induced decrease in BDNF, increase in TNF-α and decrease in reduced glutathione levels. Moreover, ANA-12 abolished the cardioprotective effects, anti-inflammatory and antioxidant effects of melatonin suggesting the role of BDNF in melatonin-mediated effects in cisplatin-induced cardiac injury. Conclusions: Melatonin is useful in cisplatin-induced cardiac injury, which may be due to an increase in BDNF, decrease in inflammation and increase in antioxidant activities.

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Introducción: Con el protocolo LPM-TOA para tratamiento de la leucemia promielocítica, se han obtenido excelentes resultados, ya que se logra sobrevida global prolongada y posible curación de los enfermos. En la inducción se utilizan dos drogas cardiotóxicas: las antraciclinas y el trióxido de arsénico y en la consolidación los enfermos reciben una dosis elevada de arsénico. Objetivo: Evaluar la toxicidad cardíaca tardía en pacientes con leucemia promielocítica tratados según el protocolo LPM-TOA. Métodos: Se realizó un estudio observacional descriptivo, prospectivo y longitudinal que incluyó 20 pacientes tratados con protocolo LPM-TOA, seguidos en consulta entre enero y julio 2019. Los pacientes tenían más de dos años de haber recibido las drogas cardiotóxicas. Se revisaron las historias clínicas y se determinó la fracción de eyección ventricular izquierda y la deformidad longitudinal global, mediante ecocardiograma. Resultados: Se presentaron hombres y mujeres con igual frecuencia, edad promedio 41,5 ± 11,0 años. Durante la inducción, en menos de la mitad de los enfermos se suspendió el arsénico por elevación del segmento QT corregido; en la mayoría solo se suspendió por uno o dos días. La mayor parte de los pacientes tuvo la fracción de eyección ventricular izquierda con valores entre 61 y 70 por ciento y la deformidad longitudinal global fue - 24 - 22 por ciento Conclusiones: En los pacientes estudiados, el tiempo de haber recibido el trióxido de arsénico y la dosis recibida, no influyó en la función cardíaca(AU)

Introduction: The PML-ATO protocol for the treatment of promyelocytic leukemia has obtained excellent results, achieving high overall survival rates and the possible healing of patients. Two cardiotoxic drugs are used in the induction process: anthracyclines and arsenic trioxide, whereas during consolidation patients receive a high dose of arsenic. Objective: Evaluate the late cardiotoxicity in patients with promyelocytic leukemia treated by the PML-ATO protocol. Methods: An observational prospective longitudinal descriptive study was conducted of 20 patients treated with the PML-ATO protocol and followed-up in outpatient consultation from January to July 2019. More than two years had elapsed since the patients received the cardiotoxic drugs. A review was carried out of the patients' medical records and echocardiographic determination was made of left ventricular ejection fraction and overall longitudinal deformity. Results: Men and women presented the same frequency; mean age was 41.5 ± 11.0 years. During induction, arsenic was suspended in less than half the patients due to corrected QT elevation. In most it was only suspended for one or two days. Most patients had left ventricular ejection fraction values between 61 percent and 70 percent, whereas overall longitudinal deformity was - 24 percent - 22 percent. Conclusions: In the patients studied, cardiac function was not affected by the time elapsed since arsenic trioxide administration or the dose received(AU)

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Las nuevas terapias oncológicas han logrado aumentar la sobrevida del paciente con cáncer, observando, sin embargo, un incremento de la morbilidad y mortalidad vinculadas a sus efectos secundarios. El desarrollo de eventos cardiovasculares adversos impacta negativamente en el pronóstico durante el tratamiento del cáncer, pero también en los supervivientes al cáncer, donde las enfermedades cardiovasculares (ECV) y las segundas neoplasias son la principal causa de muerte1-5. La cardiotoxicidad inducida por el tratamiento del cáncer se define como el conjunto de ECV derivadas de los tratamientos oncológicos. Su manifestación es variada e incluye el desarrollo de disfunción ventricular, insuficiencia cardíaca (IC), isquemia miocárdica, hipertensión arterial (HTA) y arritmias, entre otras. Puede ser consecuencia tanto del efecto directo del tratamiento sobre la estructura y función cardíacas, como del desarrollo acelerado de enfermedad cardiovascular6-9. Con frecuencia, se utiliza el término cardiotoxicidad como sinónimo de disfunción ventricular por quimioterapia (DV-QT). Dado que la cardiotoxicidad abarca un espectro más amplio de afectación cardiovascular, creemos conveniente hablar de DV-QT para referirnos a la afectación de la función sistólica del ventrículo izquierdo. La DV-QT y el desarrollo de IC representan una de las complicaciones más temidas por su impacto pronóstico en la esfera cardiovascular y oncológica, dado que limitan el arsenal terapéutico para el tratamiento del cáncer5,10. Han sido creadas diversas sociedades de cardio-onco-hematología con el fin de generar recomendaciones de práctica clínica y formar profesionales capacitados para el manejo de las complicaciones CV del tratamiento del cáncer11. La cardio-oncología es una disciplina en creciente y continuo desarrollo. Creemos que es fundamental realizar tareas de formación médica continua, así como también estimular el trabajo conjunto de diversas especialidades para brindar una mejor asistencia. Este texto es el resultado del trabajo de un equipo multidisciplinario que incluye cardiólogos, hematólogos y oncólogos, y pretende brindar información a los integrantes del equipo de salud involucrados en la asistencia de pacientes oncológicos. Debido a la extensión del presente texto, hemos decidido fraccionar el contenido en tres partes para facilitar su difusión.

New oncological therapies have been successful in increasing cancer patient survival, but they have also led to an increase in morbidity and mortality linked to their side effects. During cancer treatment, the development of cardiovascular side effects has a negative impact in prognosis, but also in cancer survivors, in whom cardiovascular diseases and secondary malignancies are the main cause of death. Cancer related cardiotoxicity is defined as the development of cardiovascular diseases related to cancer treatment. Clinical presentation is broad involving ventricular dysfunction, heart failure, myocardial ischemia, arterial hypertension and arrhythmias among others. This may result from the direct cardiovascular effect of a cancer treatment or accelerated development of cardiovascular diseases. Frequently, in the literature cardiotoxicity and chemotherapy related ventricular dysfunction are used as synonyms. However, cardiotoxicity includes a broad spectrum of cardiovascular manifestations, thus in this text we refer to chemotherapy related ventricular dysfunction as the presence of left ventricular systolic impairment. Chemotherapy related ventricular dysfunction and heart failure are two of the most feared complications of cancer treatment due to its impact on cardiovascular and oncological prognosis, affecting treatment options. Numerous worldwide cardio-onco-hematology societies have emerged to generate clinical practice guidelines and improve the diagnosis and evaluation of cardiovascular cancer treatment side effects. Cardio-Oncology is a discipline in continuous growth and development. We strongly believe that continuum medical education and a multidisciplinary approach is necessary to provide a quality health care. This text is the result of a multidisciplinary work involving cardiologists, hematologists and oncologists. It is our goal to provide information to the health care team involved in the assistance of cancer patients. Due to its extension, it will be divided in three parts.

O desenvolvimento de novas terapias oncológicas levou a um aumento na sobrevida dos pacientes, mas ao mesmo tempo traz consigo morbidades relacionadas aos tratamentos. O desenvolvimento de efeitos cardiovasculares adversos tem um impacto negativo no prognóstico dos pacientes em tratamento, bem como nos pacientes considerados curados, nos quais doença cardiovascular e malignidades secundárias são as principais causas de morte. Cardiotoxicidade relacionada ao câncer é definida como o desenvolvimento de doença cardiovascular secundária ao tratamento. A gama de apresentações clínicas é ampla, podendo se manifestar como disfunção ventricular, insuficiência cardíaca, isquemia miocárdica, hipertensão arterial, arritmias, entre outras. Isto pode ser resultante de desenvolvimento e progressão acelerados de doença cardiovascular ou por efeito direto das terapias. Frequentemente é dito na literatura que cardiotoxicidade e disfunção ventricular relacionada à quimioterapia são sinônimos. Entretanto, cardiotoxicidade engloba um amplo espectro de manifestações cardiovasculares. Neste texto, portanto, nos referimos à disfunção ventricular causada por quimioterápicos exclusivamente como a presença de disfunção sistólica ventricular esquerda. Disfunção ventricular relacionada à quimioterapia e insuficiência cardíaca são duas das mais temidas complicações do tratamento oncológico devido ao seu impacto no prognóstico cardiovascular e oncológico, podendo afetar ainda a escolha e manutenção das opções terapêuticas. Diversas sociedades cardio-onco-hematológicas surgiram ao redor do mundo com o objetivo de gerar diretriz clínicas práticas e melhorar o diagnóstico e tratamento das complicações cardiovasculares resultantes das terapias oncológicas. A cardio-oncologia é uma disciplina em contínuo crescimento e desenvolvimento. Nós acreditamos fortemente que educação médica continuada e uma abordagem multidisciplinar são necessárias para um cuidado médico de qualidade. Este texto é o resultado de um trabalho multidisciplinar envolvendo cardiologistas, hematologistas e oncologistas. Nosso objetivo é de oferecer informação à equipe de cuidados em saúde envolvido na assistência destes pacientes. Devido à sua extensão, este texto será dividido em três partes.

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El uso de medicamentos que prolongan el QT aumenta el riesgo de arritmias cardiacas, en especial taquicardia ventricular polimórfica tipo torsión de puntas (TdP), dando lugar a estancias hospitalarias prolongadas, consulta a servicios de urgencias o incluso la muerte, lo que hace importante conocerlos para prevenir este tipo de reacciones adversas incluso antes de la prescripción. Esta revisión está enfocada hacia los medicamentos de uso común tanto hospitalarios como ambulatorios que puedan producir prolongación del QT y TdP, el mecanismo por el cual se desarrolla este tipo de comorbilidad, los factores de riesgo en el paciente, el enfoque para su prevención y en caso de que se presente cómo debe ser su manejo. Los medicamentos que pueden causar prolongación del QT deben ser identificados y debidamente estudiados por parte del personal hospitalario y ambulatorio para de esta manera evitar reacciones adversas.

The use of drugs that prolong the QT interval is associated with increased risk of cardiac arrhythmias, especially torsades de pointes (TdP) type polymorphic ventricular tachycardia, leading to long hospital stays, consultation to emergency services or even death. Thus, knowing about these drugs is important to prevent this type of reactions even before prescription. This review focuses on commonly used drugs that prolong the QT interval and may induce TdP in the hospital as well as in the outpatient setting, mechanisms of QT drug-induced prolongation, pre-disposing risk factors, prevention interventions and management for these arrhythmias. The drugs inducing prolonged QT must be identified and duly studied by the hospital staff as well as the outpatient clinic staff to prevent adverse reactions.

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This study evaluated the activity of the ethanolic extract of pequi peel (EEPP) and immunostaining with matrix metalloproteinases 2 and 9 (MMP2 and MMP9), and tissue inhibitor of metalloproteinases 1 and 2 (TIMP1 and TIMP2) in the myocardium of rats subjected to acute cardiotoxicity using doxorubicin (DOX). Thirty Wistar rats (six groups of five animals) were used as follows: sham group (SG), water and saline; group G1, 16 mg/kg of DOX and 300 mg/kg of EEPP for 17 days; group G2, 16 mg/kg of DOX and 600 mg/kg of EEPP for 17 days; group G3, 16 mg/kg of DOX and 300 mg/kg of EEPP for 10 days; group G4, 16 mg/kg of DOX and 600 mg/kg of EEPP for 10 days; and control group (CG), 16 mg/kg of DOX. Three days after administering DOX (day 17), euthanasia was performed, and samples were collected for anatomopathological analysis. Myocyte vacuolar degeneration, cardiomyocyte disorganization and myofibrillar fragmentation, necrosis, mononuclear inflammatory infiltrate, Anitschkow cells, fibrosis, congestion, and edema were observed in the hearts of DOX recipients. In G1 and G2, EEPP attenuated myocyte vacuolar degeneration whereas in G4, EEPP attenuated cardiomyocyte disorganization. The percentage of cells immunoreactive for TIMP1 was higher in G1. It was concluded that EEPP minimizes the deleterious effects of DOX on rat myocardium. Doses of 300 and 600 mg/kg for 17 days attenuate the vacuolar degeneration of myocytes. The dose of 600 mg/kg for 10 days reduced cardiomyocyte disorganization, and the dose of 300 mg/kg for 17 days increased TIMP1 expression in the myocardium of DOX-treated rats.(AU)

Avaliou-se a ação do extrato etanólico da casca do pequi (EECP) e a imunomarcação de metaloproteinases de matriz 2 e 9 (MMP2 e MMP9), e inibidores teciduais das metaloproteinases de matriz 1 e 2 (TIMP1 e TIMP2), no miocárdio de ratos submetidos à cardiotoxicidade aguda pela doxorrubicina (DOX). Utilizaram-se 30 ratos Wistar, em seis grupos de cinco animais, sendo Grupo Sham (GS) água e salina; (G1) 16 mg/kg de DOX e 300 mg/kg de EECP por 17 dias; (G2) 16 mg/kg de DOX e 600 mg/kg de EECP por 17 dias; (G3) 16 mg/kg de DOX e 300 mg/kg de EECP por 10 dias; (G4) 16 mg/kg de DOX e 600 mg/kg de EECP por 10 dias; e grupo controle (GC) 16 mg/kg de DOX. Três dias após a aplicação da DOX, no dia 17, realizaram-se a eutanásia e colheita de amostras para análises antomopatológicas. No coração dos ratos que receberam DOX observaram-se degeneração vacuolar miocítica, desorganização dos cardiomiócitos e fragmentação das miofibrilas, necrose, infiltrado inflamatório mononuclear, células de Anitschkow, fibrose, congestão e edema. Nos grupos G1 e G2 o EECP atenuou a degeneração vacuolar miocítica e no G4 atenuou a desorganização dos cardiomiócitos. TIMP1 foi constatada em maior porcentagem de células marcadas no grupo de ratos que recebeu 300 mg/kg do EECP por 17 dias. Conclui-se que o EECP minimiza os efeitos deletérios da DOX no miocárdio de ratos. Nas doses de 300 e 600 mg/kg por 17 dias atenua a degeneração vacuolar miocítica, a 600 mg/kg por 10 dias reduz a desorganização dos cardiomiócitos e a 300 mg/kg por 17 dias aumenta a expressão de TIMP1 no miocárdio de ratos tratados com DOX.(AU)

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This study evaluated the activity of the ethanolic extract of pequi peel (EEPP) and immunostaining with matrix metalloproteinases 2 and 9 (MMP2 and MMP9), and tissue inhibitor of metalloproteinases 1 and 2 (TIMP1 and TIMP2) in the myocardium of rats subjected to acute cardiotoxicity using doxorubicin (DOX). Thirty Wistar rats (six groups of five animals) were used as follows: sham group (SG), water and saline; group G1, 16 mg/kg of DOX and 300 mg/kg of EEPP for 17 days; group G2, 16 mg/kg of DOX and 600 mg/kg of EEPP for 17 days; group G3, 16 mg/kg of DOX and 300 mg/kg of EEPP for 10 days; group G4, 16 mg/kg of DOX and 600 mg/kg of EEPP for 10 days; and control group (CG), 16 mg/kg of DOX. Three days after administering DOX (day 17), euthanasia was performed, and samples were collected for anatomopathological analysis. Myocyte vacuolar degeneration, cardiomyocyte disorganization and myofibrillar fragmentation, necrosis, mononuclear inflammatory infiltrate, Anitschkow cells, fibrosis, congestion, and edema were observed in the hearts of DOX recipients. In G1 and G2, EEPP attenuated myocyte vacuolar degeneration whereas in G4, EEPP attenuated cardiomyocyte disorganization. The percentage of cells immunoreactive for TIMP1 was higher in G1. It was concluded that EEPP minimizes the deleterious effects of DOX on rat myocardium. Doses of 300 and 600 mg/kg for 17 days attenuate the vacuolar degeneration of myocytes. The dose of 600 mg/kg for 10 days reduced cardiomyocyte disorganization, and the dose of 300 mg/kg for 17 days increased TIMP1 expression in the myocardium of DOX-treated rats.

Avaliou-se a ação do extrato etanólico da casca do pequi (EECP) e a imunomarcação de metaloproteinases de matriz 2 e 9 (MMP2 e MMP9), e inibidores teciduais das metaloproteinases de matriz 1 e 2 (TIMP1 e TIMP2), no miocárdio de ratos submetidos à cardiotoxicidade aguda pela doxorrubicina (DOX). Utilizaram-se 30 ratos Wistar, em seis grupos de cinco animais, sendo Grupo Sham (GS) água e salina; (G1) 16 mg/kg de DOX e 300 mg/kg de EECP por 17 dias; (G2) 16 mg/kg de DOX e 600 mg/kg de EECP por 17 dias; (G3) 16 mg/kg de DOX e 300 mg/kg de EECP por 10 dias; (G4) 16 mg/kg de DOX e 600 mg/kg de EECP por 10 dias; e grupo controle (GC) 16 mg/kg de DOX. Três dias após a aplicação da DOX, no dia 17, realizaram-se a eutanásia e colheita de amostras para análises antomopatológicas. No coração dos ratos que receberam DOX observaram-se degeneração vacuolar miocítica, desorganização dos cardiomiócitos e fragmentação das miofibrilas, necrose, infiltrado inflamatório mononuclear, células de Anitschkow, fibrose, congestão e edema. Nos grupos G1 e G2 o EECP atenuou a degeneração vacuolar miocítica e no G4 atenuou a desorganização dos cardiomiócitos. TIMP1 foi constatada em maior porcentagem de células marcadas no grupo de ratos que recebeu 300 mg/kg do EECP por 17 dias. Conclui-se que o EECP minimiza os efeitos deletérios da DOX no miocárdio de ratos. Nas doses de 300 e 600 mg/kg por 17 dias atenua a degeneração vacuolar miocítica, a 600 mg/kg por 10 dias reduz a desorganização dos cardiomiócitos e a 300 mg/kg por 17 dias aumenta a expressão de TIMP1 no miocárdio de ratos tratados com DOX.

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