Preventive effects of oleuropein against cardiac remodeling after myocardial infarction in Wistar rat through inhibiting angiotensin-converting enzyme activity.

OBJECTIVE: Myocardial infarction remains the major cause of global death due to cardiovascular diseases. This study aimed to assess the protective role of oleuropein in attenuating the cardiac remodeling in isoproterenol-induced myocardial infarction in rats. METHODS AND RESULTS: Male Wistar rats were randomly divided into four groups, control, isoproterenol (Isop) and pretreated animals with oleuropein at two different doses (20 and 40 mg/kg) orally for 7 days and intoxicated with isoproterenol (Isop+Oleu20) and (Isop+Oleu40) groups. The subcutaneous injection of isoproterenol (100 mg/kg body weight) to untreated rats for two consecutive days showed significant increases in ST-segment elevation, heart weight index and alteration in the ECG pattern and hemodynamic function. Else, serum levels of cardiac troponin-T, creatine kinase isoenzyme (CK-MB), lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) underwent a notable rise in serum of Isop group by (345, 82, 73 and 106%, respectively) as compared to normal rats. Isoproterenol-induced myocardial injury was evidenced by alteration in serum lipids profile and increased activities of pancreatic lipase by 94% and angiotensin-converting enzyme (ACE) by 78% which reflects the occurrence of cardiac remodeling process. The histopathological findings of the infarcted group showed myocardium necrosis and cells inflammatory infiltration. However, the treatment with oleuropein gave a good protection of the myocardium by decreasing cardiac injury markers specially troponin-T, restoring hemodynamic parameters and attenuating cardiac remodeling process through inhibition of ACE activity. CONCLUSION: Oleuropein offers high preventive effects from cardiac remodeling process in rats with acute myocardial infarction.

[Acute myocardial infarction in elderly patients]. / Infarctus du myocarde chez le sujet âgé.

BACKGROUND: Age is the most important determinant of outcome for patients with acute coronary syndromes (ACS) and ischemic heart disease is the leading cause of death among elderly patients. AIM: To determine the epidemiologic particularities, the clinical presentation, and the treatment of Acute Myocardial Infarction (AMI) in patients over 65 years. METHODS: One hundred patients >65 years of age with myocardial infarction were hospitalized in intensive care of cardiologic unit of Military Hospital of Tunis between 2000 and 2008. Clinical characteristics, reperfusion therapy and outcomes of in-hospital period and for one year follow-up were seen for every patient. RESULTS: The mean age of our population was 77 years. Sex-ratio was 3/1.Our population was divided into tow groups; patients aged between 65 and 75 years (48 patients) and those aged more than 75 years (52 patients). Only 44 % of our patients had arrived at the hospital within the first 12 hours. STEMI was found in 65 % of our patients. At admission, 40 % had congestive heart failure (³ Killip II), 10 % were in cardiogenic shock. Urgent reperfusion therapy was given to 58 % of our patients; 33% received a thrombolytic therapy and 25 % were allocated to primary PCI. During in-hospital period, 40 % have developed congestive heart failure, 20 % have had a cardiogenic shock and 12 % were died. All these events were more frequent in patients aged over 75 years and reperfusion therapy was associated with best outcome. CONCLUSION: In our study invasive treatment such as fibrinolysis and PCI was associated to better outcome in acute period and at 12 months of follow up in elderly patients treated for AMI.

Protective Effect of Hydroxytyrosol Against Cardiac Remodeling After Isoproterenol-Induced Myocardial Infarction in Rat.

The present study aimed to investigate the cardioprotective effect of hydroxytyrosol (HT) against isoproterenol-induced myocardial infarction in rats. Male rats were randomly divided into four groups, control, isoproterenol (Isop) and pretreated animals with HT in two different doses (2 and 5 mg/kg) orally for 7 days and intoxicated with isoproterenol (Isop + HT1) and (Isop + HT2) groups. Myocardial infarction in rats was induced subcutaneously by isoproterenol (100 mg/kg, s.c.) at an interval of 24 h on 6th and 7th day. On 8th day, electrocardiographic (ECG) pattern, gravimetric and biochemical parameters were assessed. Isoproterenol exhibited changes in ECG pattern, including significant ST-segment elevation and increase in the serum troponin-T level by 317 % as compared to control rats. Moreover, cardiac injury markers (creatine kinase-MB, lactate dehydrogenase, alanine aminotransferase) underwent a notable rise in serum of infarcted animals. Else, a disturbance in lipids profile and significant increase in lipase and angiotensin-converting enzyme (ACE) activities and heart weight ratio were observed in isoproterenol group. However, pre- and co-treatment with HT (2 and 5 mg/kg) improved the myocardium injury, restored the hemodynamic function and inhibited the ACE activity that prevent cardiac hypertrophy and remodeling. Overall, these findings demonstrated that HT exerted a potent cardioprotective effect against isoproterenol-induced myocardial infarction.

Anti-inflammatory, Antithrombotic and Cardiac Remodeling Preventive Effects of Eugenol in Isoproterenol-Induced Myocardial Infarction in Wistar Rat.

This study aimed to evaluate the antithrombotic, anti-inflammatory and anti-cardiac remodeling properties of eugenol in isoproterenol-induced myocardial infarction in rats. Male Wistar rats were randomly divided into four groups, control, iso [100 mg/kg body weight was injected subcutaneously into rats at an interval of 24 h for 2 days (6th and 7th day) to induce MI] and pretreated animals with clopidogrel (0.2 mg/kg) and eugenol (50 mg/kg) orally for 7 days and intoxicated with isoproterenol (Iso + Clop) and (Iso + EG) groups. Isoproterenol-induced myocardial infarcted rats showed notable changes in the ECG pattern, increase in heart weight index, deterioration in the hemodynamic function and rise in plasma level of troponin-T, CK-MB and LDH and ALT by 316, 74, 172 and 45 %, respectively, with histological myocardium necrosis and cells inflammatory infiltration. In addition, significant increases in plasma levels of inflammatory biomarkers such as fibrinogen, α1, α2, ß1, ß2 and γ globulins with decrease level of albumin were observed in infarcted rats as compared to normal ones. Else, the angiotensin-converting enzyme (ACE) activity in plasma, kidney and heart of the isoproterenol-induced rats was significantly increased by 34, 47 and 93 %, respectively, as compared to normal group. However, the administration of eugenol induced a clear improvement in cardiac biomarkers injury, reduced inflammatory mediators proteins, increased heart activities of superoxide dismutase and glutathione peroxidase with reduce in thiobarbituric acid-reactive substances content and inhibition of ventricular remodeling process through inhibition of ACE activity. Overall, eugenol evidences high preventive effects from cardiac remodeling process.