Pleiotropic Effects of Simvastatin on Some Calcium Regulatory and Myofibrillar Proteins in Ischemic/Reperfused Heart: Causality of Statins Cardioprotection?

Background: It is known that statins possess beneficial cardioprotective effects irrespective of lipidlowering action and that cardiac injury due ischemia/reperfusion is associated with Ca2+ dysregulation resulting in contractile dysfunction.

Objective: With this background, we tested a hypothesis that simvastatin influences signaling of Ca2+/calmodulindependent protein kinase IIδ (CaMKIIδ), a protein kinase regulating both Ca2+ homeostasis and thick filament function, and thereby might underlie the mitigation of ischemia/reperfusion (I/R)-induced cardiac dysfunction.

Method: Isolated hearts of control and simvastatin-treated (p.

Impact of age and sex on response to ischemic preconditioning in the rat heart: differential role of the PI3K-AKT pathway.

Sex and aging represent important factors that determine morbidity and mortality due to cardiovascular diseases in the human population. This study aimed to investigate the impact of aging on the response to ischemia-reperfusion in male and female rat hearts, and to explore a potential role of the PI3K-Akt pathway in the cardioprotective effects of ischemic preconditioning (IPC) in the myocardium of younger and older adult males and females. Langendorff-perfused nonpreconditioned and preconditioned hearts of 12- and 18-week-old male and female Wistar rats were subjected to regional ischemia and reperfusion with or without prior perfusion with the PI3K inhibitor wortmannin for the evaluation of ischemia-induced arrhythmias and the size of myocardial infarction (infarct size; IS).

Activation of Akt kinase accompanies increased cardiac resistance to ischemia/reperfusion in rats after short-term feeding with lard-based high-fat diet and increased sucrose intake.

High-fat or high-carbohydrate food consumption contributes to changes in myocardial tolerance to ischemia. However, with respect to experimental models, most studies used diets with very high doses of cholesterol, saturated fatty acids, or fructose. In our study, we fed rats a high-fat diet based on lard in combination with administration of a sweet beverage (30% sucrose solution) (high-fat sucrose diet [HFS]).

Hemidesmus indicus and Hibiscus rosa-sinensis Affect Ischemia Reperfusion Injury in Isolated Rat Hearts.

Hemidesmus indicus (L.) R. Br.

Acute treatment with polyphenol quercetin improves postischemic recovery of isolated perfused rat hearts after global ischemia.

Quercetin is a plant-derived bioflavonoid with potentially beneficial effects on the cardiovascular system. Studies focused on the efficiency of flavonoids against ischemia-reperfusion (I/R) injury have demonstrated that quercetin exerts robust protective effects in renal, cerebral, and hepatic I/R models. However, there is only limited evidence about the effect of quercetin on myocardial I/R injury.

Mitochondrial KATP opening confers protection against lethal myocardial injury and ischaemia-induced arrhythmias in the rat heart via PI3K/Akt-dependent and -independent mechanisms.

Opening of mitochondrial KATP channels (mitoKATP) has been reported to underlie protection against ischaemia-reperfusion injury induced by ischaemic preconditioning (I-PC); however, the molecular mechanisms of its antiarrhythmic effect have not been fully elucidated. We explored the involvement of phosphatidylinositol 3-kinase (PI3K)/Akt in the PC-like effect of mitoKATP opener diazoxide with particular regard to its role in protection against ischaemia-induced arrhythmias. Langendorff-perfused rat hearts were subjected to 30 min LAD occlusion with or without a prior 15 min of perfusion with diazoxide (50 micromol/L) given either alone (D-PC) or in combination with the PI3K/Akt inhibitor wortmannin (100 nmol/L).

Changes in PPAR gene expression and myocardial tolerance to ischaemia: relevance to pleiotropic effects of statins.

Peroxisome proliferator-activated receptors (PPAR), which are key transcriptional regulators of lipid metabolism and energy production, have been suggested to play an important role in myocardial ischaemia-reperfusion (I/R) injury. Their role in cardioprotection, however, is not yet fully elucidated. Statins have shown beneficial effects on I/R damage beyond lipid lowering, and some of their cardioprotective cholesterol-independent effects may be related to the regulation of PPAR.

Oxytocin exerts protective effects on in vitro myocardial injury induced by ischemia and reperfusion.

Among the cardiovascular pathologies, ischemic heart disease is a serious medical problem that can result in cardiac injury and (or) heart failure. The aim of the present study was to test the hypothesis that neuropeptide oxytocin induces cardioprotective effects on ischemia-reperfusion-induced myocardial damage. The functional parameters of isolated Langendorff-perfused rat hearts were recorded before and after global 25 min ischemia and subsequent reperfusion.