Resveratrol activates PI3K/AKT to reduce myocardial cell apoptosis and mitochondrial oxidative damage caused by myocardial ischemia/reperfusion injury.

Resveratrol is a kind of iPolyphenols widely existing in herbal medicine. Here we aim to investigate whether resveratrol can reduce the degree of myocardial ischemia/reperfusion (IR) injury and inhibit the development of oxidative stress, and elucidate the molecular mechanism of resveratrol in protecting myocardial cells. The primary rat cardiomyocytes were used to establish an ischemia/reperfusion model in vitro, and a series of routine biochemical experiments were conducted to explore the antioxidant and anti-apoptotic effects of resveratrol in myocardial ischemia-reperfusion injury. Compared with that of the simulated ischemia-refusion (SIR) group, cell viability in the SIR and resveratrol co-treatment groups increased significantly (P < 0.001), the release of lactate dehydrogenase (LDH) and creatine kinase MB (CKMB) decreased, the positive rate of reactive oxygen species (ROS) in cardiomyocytes decreased, and the concentration of catalase and glutathione peroxidase increased significantly (P < 0.001). Besides, resveratrol can activate PI3K/AKT signaling pathway. PI3K siRNA can inhibit the PI3K/AKT signaling mediated by resveratrol. The addition of resveratrol can significantly increase the activity of mitochondrial superoxide dismutase (SOD) and reduce the malondialdehyde (MDA), which indicates that the oxidative damage of mitochondria induced by resveratrol was significantly weakened. The mitochondrial functional changes induced by resveratrol can be reversed by PI3K siRNA. In conclusion, our study shows that resveratrol can reduce ROS in cardiomyocytes by PI3K/AKT signaling pathway activation, and effectively inhibit the apoptosis of cardiomyocytes, thus having a direct protective effect on cardiomyocytes under SR.

Chrysin attenuates cardiomyocyte apoptosis and loss of intermediate filaments in a mouse model of mitoxantrone cardiotoxicity.

Chrysin (CHR) is a natural flavonoid and is present in high concentration in honey, propolis and many plant extracts. The aim of the present study was to evaluate the effects of CHR to reduce cardiomyocyte apoptosis and loss of intermediate filaments in a mouse model of mitoxantrone cardiotoxicity. Morphology of the cardiomyocytes was determined by optic and transmission electron microscopy and biochemistry methods. The expression of Bcl-2, Bax and Caspase-3 were assessed by immunofluorecence. Tunel assay was used to assess apoptosis in cardiomyocytes. In addition, the distribution of desmin protein was evaluated using immunohistochemistry. Our results show that MTX treatment significantly increased serum levels of creatine kinase isoenzyme (CK-MB), indicator of cardiac injury and withdrawn under CHR protection. Expression levels of Bcl-2 decreased, while those of Bax and caspase-3 increased following MTX treatment. 50 mg/kg of daily CHR intake reduced Bax and caspase-3 immunopositivity and restored Bcl-2 levels to a value comparable to the control. TUNEL (+) cardiomyocyte nuclei of MTX group showed typical signs of apoptosis which almost completely disappeared in response to 50 mg/kg CHR treatment. In parallel, an irregular distribution and a weak expression of desmin is associated with MTX induced cardiotoxic effects which was also restored by CHR treatment. In conclusion chrysin inhibits MTX-triggered cardiomyocyte apoptosis via multiple pathways, including decrease of the Bax/Bcl-2 ratio and caspase-3 expression along with preservation of the desmin disarray.

Myocardial infarction marker levels are influenced by prothrombin and tumor necrosis factor-α gene polymorphisms in young patients.

Polymorphisms of genes encoding key factors for the control and activation of inflammatory response and coagulation cascade regulation may play a role in genetic susceptibility to acute myocardial infarction (AMI). This study sought to analyze the effect of TNF -308G/A and pro-thrombin (FII) 20210G/A polymorphisms on the laboratory parameters of young patients affected by AMI. Results indicated that TNF -308A positive genotype frequencies were increased in these patients and that a genetically determined higher production of TNF-α is associated in young subjects to a more severe cardiac damage as depicted by higher levels of troponin, Creatine kinase-MB Isoenzyme (mCK-MB) and a significant increased plasma fibrinogen levels. Similar and probably additive effects on might have a genetically determined increased production of pro-thrombin even if no significant differences in genotype frequencies of pro-thrombin (FII) 20210G/A polymorphisms were observed in this study. All together these results, indicating the relationship among genetically determined TNFα and FII production and increased levels of tissue damage markers of AMI, suggest that a complex genetic background, might be involved in susceptibility to AMI in young men influencing the extension and severity of the disease.

Usefulness of heart-type fatty acid-binding protein in patients with severe sepsis.

PURPOSE: The purpose of the study was to evaluate the value of heart-type fatty acid-binding protein (hFABP) as a novel clinical biomarker in patients with severe sepsis. METHODS: Serum concentrations of hFABP and traditional cardiac biomarkers including cardiac troponin I, creatine kinase-MB, and B-type natriuretic peptides levels were measured within 6 hours after admission in 93 severe septic patients. The value of hFABP for the diagnosis of sepsis-related myocardial dysfunction (SRMD) and for the prediction of 28-day mortality was evaluated by receiver operating characteristics curve analysis. The prognostic value of elevated hFABP was subsequently confirmed by multivariate Cox proportional hazards analysis and Kaplan-Meier survival analysis. RESULTS: Heart-type fatty acid-binding protein was elevated (≥ 4.5 ng/mL) in 58 (62.4%) patients; patients with elevated hFABP appeared more likely to have SRMD (84.5% vs 31.4%, P < .001) and have higher prevalence of 28-day death (37.9% vs 8.6%, P = .002). Heart-type fatty acid-binding protein offered superior value over conventional biomarkers in both diagnosis of SRMD (area under the curve, 0.767; P < .001) and prediction of 28-day death (area under the curve, 0.805; P < .001). CONCLUSIONS: Serum hFABP is frequently elevated among patients with severe sepsis and appears to be associated with SRMD. Elevated hFABP independently predicts 28-day mortality in severe sepsis.

High serum levels of pro-brain natriuretic peptide (pro BNP) identify cardioembolic origin in undetermined stroke.

BACKGROUND: Stroke subtype diagnosis leads to specific therapies to reduce recurrences. Because nearly one third of patients remain with unknown etiology after a complete screening workup, we aim to investigate whether molecular markers of myocardial damage were associated with cardioembolic stroke and if they were useful to reclassify strokes of undetermined etiology. METHODS: We included 262 patients with first ischemic stroke within the first 12 hours. Stroke subtype was evaluated by TOAST criteria. Stroke of undetermined origin were reclassified into likely atherothrombotic or likely cardioembolic according to a predefined non-validated algorithm. Blood samples were obtained on admission to determine serum levels of molecular markers (pro-BNP, pro-ANP and CK-MB) of myocardial damage. RESULTS: Patients with cardioembolic infarct showed higher levels of pro-BNP, pro-ANP and CK-MB. Pro-BNP > 360 pg/mL was independently associated with cardioembolic stroke (OR: 28.51, CI95%: 5.90-136.75, p< 0.0001). Stroke etiology was undetermined in 82 patients (31%); 34 were reclassified as likely cardioembolic, 22 as likely atherothrombotic, and 26 remained as undetermined. Pro-BNP > 360 pg/mL was the only factor independently associated with likely cardioembolic stroke. CONCLUSIONS: Pro-BNP levels higher than 360 pg/mL are associated with cardioembolic stroke and may be useful to reclassify undetermined strokes as of cardioembolic origin.