Potentilla reptans L. preconditioning regulates H19 and MIAT long noncoding RNAs in H9C2 myoblasts Ischemia/Reperfusion model

The present study aimed to evaluate the effect of the ethyl acetate fraction of P. reptans root (PEF) preconditioning on expressions of lncRNAs H19 and MIAT in H9C2 myoblasts I/R injury.H9C2 cells were treated with different concentrations ranging from (10-400 µg/ml) of PEF for 24 h, followed by simulation of I/R condition. For I/R experiments, H9C2 cells were subjected with the oxygen and glucose deprivation for 2 h.H9C2 cell viability was significantly enhanced by PEF preconditioning under I/R condition in a concentration-dependent manner up to 200 µg/ml as a EC₅₀. The PEF significantly diminished the expression of lncRNA MIAT and rate of apoptosis against the I/R group. In addition, PEF pretreated before stimulation I/R condition increased H19 expression compared to the normal PEF group with no statistically significant differences between groups. Hence, the results suggest that PEF can protect cardiomyocytes during hypoxia-induced myocardial cell injury by targeting specific involved genes.

Sigma-1 Receptor Stimulation with PRE-084 Ameliorates Myocardial Ischemia-Reperfusion Injury in Rats

BACKGROUND

The sigma receptors are a relatively novel receptor group with respect to knowledge of their effect on health. Although the sigma-1 receptor agonist PRE-084 exhibits a cardioprotective effect in some studies, the benefits in cases of myocardial ischemia/reperfusion (I/R) are not clear. The aim of this study was to explore the mechanism of action and assess the effect of PRE-084 on myocardial I/R injury in rats.

METHODS

In this study, rats were assigned randomly to three groups with computer (n = 14 for each group): a sham group, an I/R group, and a PRE-084 group. In the PRE-084 group, rats were administered PRE-084 1 h before operation. In the myocardial I/R model, the left anterior descending branch of rats was ligated and opened half an hour later. Cardiac function was assessed, and the apoptosis index was evaluated. The mechanisms of the cardioprotective effects of PRE-084 were explored.

RESULTS

PRE-084 pretreatment preserved cardiac function and reduced myocardial apoptosis (F = 86.0, P < 0.01) with Western blotting analysis, showing significantly reduced expression of Bax (F = 75.7, P < 0.01) and cleaved-caspase 3 (F = 44.7, P < 0.01), along with increased expression of the Bcl-2 protein (P < 0.01) and phosphorylated protein kinase B (p-Akt) (P < 0.01) and phosphorylated-endothelial nitric oxide synthase (p-eNOS; P < 0.01).

CONCLUSION

PRE-084 preserved cardiac function and reduced myocardial apoptosis through the activation of Akt and eNOS.

Crocin-Elicited Autophagy Rescues Myocardial Ischemia/Reperfusion Injury via Paradoxical Mechanisms

Crocin, the main effective component of saffron, exerts protective effects against ischemia/reperfusion injury during strokes. However, the effects of crocin in myocardial ischemia/reperfusion injury, and the mechanisms involved, remain unknown. Pretreated with crocin for 7 days, C57BL/6N mice were subjected to 30 min of myocardial ischemia followed by 12[Formula: see text]h of reperfusion (for cardiac function and infarct size, cell apoptosis and necrosis). Neonatal mouse cardiomyocytes were subjected to 2 h of hypoxia followed by 4 h of reoxygenation. NMCM's survival was assessed during hypoxia and reoxygenation in the presence or absence of the autophagy inhibitor 3-methyladenine or the inducer rapamycin. Western blotting was used to evaluate AMPK, Akt, and autophagy-related proteins. Autophagosome was observed using electron microscopy. In the in vivo experiment, crocin pretreatment significantly attenuated infarct size, myocardial apoptosis and necrosis, and improved left ventricular function following ischemia/reperfusion. In vitro data revealed that autophagy was induced during hypoxia, the levels of which were intensely elevated during reoxygenation. Crocin significantly promoted autophagy during ischemia, accompanied with the activation of AMPK. In contrast, crocin overtly inhibited autophagy during reperfusion, accompanied with Akt activation. Induction and inhibition of autophagy mitigated crocin induced protection against NMCMs injury during hypoxia and reoxygenation, respectively. Our data suggest that crocin demonstrated a myocardial protective effect via AMPK/mTOR and Akt/mTOR regulated autophagy against ischemia and reperfusion injury, respectively.