RESUMO
Myocardial infarction (MI) is the primary source of death in cardiovascular diseases. Myricitrin (MYR) is a phenolic compound known for its antioxidant properties. This study aimed to investigate the impact of MYR alone or combined with exercise on a rat model of MI and its underlying mechanism. Sprague-Dawley rats were randomized into 5 groups: sham-operated (Sham), MI-sedentary (MI-Sed), MI-exercise (MI-Ex), MI-sedentary + MYR (MI-Sed-MYR) and MI-exercise + MYR (MI-Ex-MYR). MI was induced through ligation of left anterior descending coronary artery. The treatment with exercise or MYR (30 mg/kg/d) gavage began one week after surgery, either individually or in combination. After 8 weeks, the rats were assessed for cardiac function. Myocardial injuries were estimated using triphenyltetrazolium chloride, sirius red and Masson staining. Changes in reactive oxygen species (ROS) levels, mitochondrial membrane potential (ΔΨm), apoptosis and Nrf2/HO-1 pathway were analyzed by ROS kit, JC-1 kit, TUNEL assay, Western blot and immunohistochemistry. Both MYR and exercise treatments improved cardiac function, reduced infarct size, suppressed collagen deposition, and decreased myocardial fibrosis. Additionally, both MYR and exercise treatments lowered ROS production induced by MI, restored ΔΨm, and attenuated oxidative stress and apoptosis in cardiomyocytes. Importantly, the combination of MYR and exercise showed greater efficacy compared to individual treatments. Mechanistically, the combined intervention activated the Nrf2/HO-1 signaling pathway. These findings suggest that the synergistic effect of MYR and exercise may offer a promising therapeutic approach for alleviating MI.
RESUMO
This study investigated the effects of amygdalin (AMY, a cyanogenic glycoside widely distributed in the fruits and seeds of Rosaceae plants) on cardiac performance and ventricular remodeling in a rat model of myocardial infarction (MI). We also investigated whether the combination of AMY with exercise training (ExT) has a beneficial synergistic effect in treating MI rats. MI was induced by the ligation of the left anterior descending coronary artery in male SD rats. ExT or AMY treatment was started 1 week after MI and continued for 1 week (short-term) or 8 weeks (long-term). Cardiac function was evaluated by echocardiographic and hemodynamic parameters. Heart tissues were harvested and subjected to 2,3,5-triphenyl-tetrazolium chloride, Masson's trichrome, hematoxylin-eosin, and immunohistochemical staining. Gene expression was determined by quantitative polymerase chain reaction. Western blot gave a qualitative assessment of protein levels. AMY or ExT improved cardiac function and reduced infarct size in MI rats. AMY or ExT also suppressed myocardial fibrosis and attenuated inflammation in the infarct border zone of hearts from MI rats, as evidenced by inhibition of collagen deposition, inflammatory cell infiltration, and pro-inflammatory markers (interleukin 1ß, interleukin 6, tumor necrosis factor-α, and cyclooxygenase 2). Notably, the effects of AMY combined with ExT were superior to those of AMY alone or ExT alone. Mechanistically, these beneficial functions were correlated with the inhibition of MI-induced activation of the transforming growth factor-ß/Smad pathway. Collectively, AMY and ExT exert a synergistic effect on improving cardiac performance and ameliorating cardiac inflammation and fibrosis after MI, and the effects of long-term intervention were better than short-term intervention.
Assuntos
Amigdalina , Infarto do Miocárdio , Animais , Ratos , Ratos Sprague-Dawley , Amigdalina/farmacologia , Infarto do Miocárdio/terapia , Inflamação/terapia , FibroseRESUMO
OBJECTIVE: To explore the effects of gender on treatment strategies for elderly patients with acute coronary syndrome (ACS). METHODS: March 2009 to March 2012, consecutive 619 aged ACS patients undergoing coronary angiography (CA) were screened at our hospital. There were 273 females and 346 males. Risk factors, ACS diagnosis, CA results, treatments and prognosis were compared between female and male groups. RESULTS: The risk factors of body mass index, stroke history, smoking history, hemoglobin (Hb), serum cholesterol (TC), low density lipoprotein (LDL-C) and blood uric acid (UA) levels were significantly lower in female group than those in male group (P < 0.05). The morbidity of diabetes in female group was obviously higher than that in male group (27.8% vs 18.5%, P < 0.05). The prevalence of myocardial infarction history, percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) history in male group were significantly greater than that in female group (48.0% vs 39.9%, P < 0.05; 30.6% vs 22.3%, P < 0.05; 19.9% vs 10.3%, P < 0.01). The rate of combined multiple risk factors (3 or higher) increased significantly in female group (41.8% vs 29.8%, P < 0.05). The incidence of unstable angina pectoris (UAP) and non-ST segment elevation myocardial infarction (NSTEMI) in female group was greater, but there was no statistical significance. The rate of 3-vessel and calcification lesions in female group was significantly elevated compared with male group (36.26% vs 28.61%, P < 0.05). Regarding the choice of treatment strategy, conservative treatment was common in females, but there was no statistical significance between them. PCI, emergency PCI and selective CABG operation were performed more frequently in female group compared with male group (26.0% vs 14.2%, P < 0.01; 14.7% vs 6.6%, P < 0.01; 19.1% vs 7.7%, P < 0.01). The prognosis had no statistical significance between two groups. CONCLUSION: The treatment strategies have certain limitations for female ACS patients. And an more aggressive treatment should be offered to improve the prognosis.