Mediterranean diet and cardioprotection: Wild artichoke inhibits metalloproteinase 9

Involvement of Bcl-2 Signal Pathway in the Protective Effects of Apigenin on Anoxia/Reoxygenation-induced Myocardium Injury

Apigenin is a type of flavonoids, which has been demonstrated to protect myocardium against ischemia/reperfusion (I/R) injury. However, the mechanism is still unclear. We hypothesized that the mechanism of cardioprotective action of apigenin on the I/R-induced injury might be caused via B-cell lymphoma (Bcl) signaling pathway. In this study, an in vitro I/R model was replicated on Langendorff-perfused heart and H9c2 cardiomyocytes by anoxia/reoxygenation (A/R) treatment. The recovery of cardiac contractile function, infarct size, lactate dehydrogenase (LDH) and creatine kinase (CK) in the perfusate, the expression and activity of Bcl-2 and caspase-3, and cardiomyocyte apoptosis were measured in the Langendorff heart undergoing A/R injury. In addition, the cell viability, LDH release, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (Δψm), expression of cytochrome c in the cytosol, and cell apoptosis were examined in the culture of H9c2 cardiomyocytes after the A/R. The results showed that apigenin significantly improved rat heart contractile function, reduced LDH release, infarct size and apoptotic rate, upregulated the expression of Bcl-2 and caspase-3, and downregulated the expression of cleaved caspase-3 after the A/R. Moreover, apigenin increased the cell viability and decreased the release of LDH, production of reactive oxygen species, release of mitochondrial cytochrome c into the cytosol, and cell apoptosis in the culture of H9c2 cardiomyocytes after the A/R. In addition, inhibition of Bcl-2 activity by ABT-737 markedly attenuated the protective effect of apigenin on the A/R-induced myocardium injury. Taken together, we firstly demonstrated that the effect of apigenin against A/R injury in cardiomyocytes involves Bcl-2 signal pathway and at least partly depends on its effect of upregulating the expression of Bcl-2.

Protective effect of apigenin on ischemia/reperfusion injury of the isolated rat heart

Apigenin (Api), a mainly bioactive component of Apium graveolens L. var. dulce DC. (a traditional Chinese medicinal herb), possesses a wide range of biological activities, including antioxidant effects. It also has been shown to associate with lower prevalence of cardiovascular diseases, but its mechanisms of action remain unclear. The aim of the present study is to investigate the role of Api in isolated rat heart model of ischemia/reperfusion (I/R). Langendorff-perfused isolated rat hearts were used in our study. Api was added to the perfusate before ischemia and during reperfusion in the isolated pulsed rat heart exposed to 30-min ischemia followed by 50-min reperfusion. The treatment with Api conferred a cardioprotective effect, and the treated hearts demonstrated an improved ischemic cardiac functional recovery, a decreased myocardial infarct size, a reduced activities of creatine kinase isoenzyme and lactate dehydrogenase in the coronary flow, a reduced number of apoptotic cardiomyocytes, a reduced activity of caspase-3, up-regulation of the anti-apoptotic protein Bcl-2 and down-regulation of the pro-apoptotic protein Bax. In addition, Api inhibited the phosphorylation of p38 MAPKS during I/R. In conclusion, these observations provide preliminary evidence that Api can protect cardiomyocytes from I-/R-induced injury, at least partially, through the inhibition of p38 MAPKS signaling pathway.

Apigenin attenuates myocardial ischemia/reperfusion injury via the inactivation of p38 mitogen‑activated protein kinase

Apigenin (Api) is a plant monomer associated with reducing the risk of heart disease. However, the mechanism of action remains to be fully elucidated. In the present study, it was hypothesized that API has cardioprotective effects by attenuating myocardial ischemia/reperfusion (I/R) injury. Rats were randomly subjected to sham operation, myocardial I/R alone or I/R + Api. Cardiac function was measured, and infarct size was evaluated by triphenyltetrazolium chloride staining following reperfusion. The myocardial enzyme leakage was analyzed for lactate dehydrogenase (LDH) and creatine kinase (CK). The myocardium was also assessed for total superoxide dismutase (SOD) activity and malondialdehyde (MDA) content. The phosphorylation of p38 mitogen‑activated protein kinase (MAPK) was analyzed by western blotting. The present study reported for the first time, to the best of our knowledge, that I/R significantly increased infarct size, induced CK and LDH release, inhibited the activity of SOD and increased the levels of MDA, all of which were prevented by treatment with Api. In addition, I/R increased the phosphorylation of p38 MAPK, which was significantly decreased in the Api‑treated heart tissue samples following I/R, compared with the untreated heart tissue samples. In conclusion, the results of the present study demonstrated that Api inhibited the p38 MAPK signaling pathway to protect cardiomyocytes from I/R‑induced injury.

Postischemic administration of liposome-encapsulated luteolin prevents against ischemia-reperfusion injury in a rat middle cerebral artery occlusion model

Oxidative stress-induced neuronal cell death has been implicated in neurodegenerative diseases; one such disease is ischemic stroke. Using reactive oxygen species (ROS)-insulted primary neurons, we screened neuroprotectants with clinical potential and then, using ischemia/reperfusion (I/R) model, investigated the anti-ischemic potential of candidate neuroprotectants. Here, we showed that luteolin, isolated from the ripe fruit of Perilla frutescens (L.) Britt, exhibited a neuroprotective action upon the in vitro platform, thus serving as candidate for in vivo pharmacological evaluation. Liposome-encapsulated luteolin produced dramatic preventing effects on I/R-induced behavioral and histological injuries after a 13-day post-ischemic treatment. Furthermore, this phytochemical not only lowered the increased level of mitochondrial ROS but also substantially up-regulated the decreased activity of catalase and glutathione in I/R rat brains. Collectively, luteolin as a neuroprotectant acts by anti-ischemic activity likely through a rebalancing of pro-oxidant/antioxidant status. Its multitarget mechanisms implicate potential effectiveness for clinically treating ischemia stroke.