RESUMO
There is an increase in oxidative stress and apoptosis signaling during the transition from hypertrophy to right ventricular (RV) failure caused by pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT). In this study, it was evaluated the action of copaiba oil on the modulation of proteins involved in RV apoptosis signaling in rats with PAH. Male Wistar rats (±170 g, n = 7/group) were divided into 4 groups: control, MCT, copaiba oil, and MCT + copaiba oil. PAH was induced by MCT (60 mg/kg intraperitoneally) and, 7 days later, treatment with copaiba oil (400 mg/kg by gavage) was given for 14 days. Echocardiographic and hemodynamic measurements were performed, and the RV was collected for morphometric evaluations, oxidative stress, apoptosis, and cell survival signaling, and eNOS protein expression. Copaiba oil reduced RV hypertrophy (24%), improved RV systolic function, and reduced RV end-diastolic pressure, increased total sulfhydryl levels and eNOS protein expression, reduced lipid and protein oxidation, and the expression of proteins involved in apoptosis signaling in the RV of MCT + copaiba oil as compared to MCT group. In conclusion, copaiba oil reduced oxidative stress, and apoptosis signaling in RV of rats with PAH, which may be associated with an improvement in cardiac function caused by this compound.
Assuntos
Apoptose/efeitos dos fármacos , Fármacos Cardiovasculares/farmacologia , Fabaceae , Hipertensão Pulmonar/tratamento farmacológico , Hipertrofia Ventricular Direita/prevenção & controle , Monocrotalina , Miocárdio , Óleos de Plantas/farmacologia , Disfunção Ventricular Direita/prevenção & controle , Função Ventricular Direita/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Animais , Fármacos Cardiovasculares/isolamento & purificação , Modelos Animais de Doenças , Fabaceae/química , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Hipertrofia Ventricular Direita/induzido quimicamente , Hipertrofia Ventricular Direita/metabolismo , Hipertrofia Ventricular Direita/patologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Óleos de Plantas/isolamento & purificação , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Disfunção Ventricular Direita/induzido quimicamente , Disfunção Ventricular Direita/metabolismo , Disfunção Ventricular Direita/patologia , Proteína X Associada a bcl-2/metabolismoRESUMO
BACKGROUND: Tumour Necrosis Factor alpha (TNFalpha) has been shown to contribute to heart failure (CHF) progression. AIMS: We have tried to antagonise the detrimental effects of TNFalpha on skeletal muscle apoptosis, by using thalidomide, a drug that inhibits its biosynthesis. METHODS: CHF was induced in 20 rats by injecting monocrotaline, which determines right ventricle (RV) failure. After 2 weeks, when CHF developed, 12 rats were treated with thalidomide 3.5.mg/kg per day for 2 weeks. Eight had saline and served as CHF controls. RESULTS: Thalidomide failed to decrease TNFalpha and its second messenger sphingosine (SPH), but was able to prevent the shift toward the fast myosin heavy chains. In the Tibialis Anterior muscle of the thalidomide group, the degree of atrophy, the number of apoptotic nuclei and the levels of caspases, were similar to those of the CHF controls. CONCLUSIONS: Thalidomide, at the doses used in this study, which are the same employed for the treatment of tubercolosis, leprosy, AIDS and cancer in humans, did not lower either TNFalpha or SPH and only marginally influenced the apoptosis-induced muscle atrophy. Since other TNFalpha blockers are under investigation for improving the clinical status of patients with CHF, the present data could be relevant in the design of randomised clinical trials in humans.