Protective Effect and Mechanism of Traditional Chinese Medicine on Myocardial Ischemia Reperfusion Injury

Puerarin from Pueraria lobate attenuates ischemia-induced cardiac injuries and inflammation in vitro and in vivo: The key role of miR-130a-5p/HMGB2 pathway

Acute myocardial infarction (AMI) is a common cardiovascular disease and puerarin (Pue) is an active compound from Pueraria lobate with cardio-protective potential. In the current study, the mechanism underlying the cardio-protective effects of Pue was explored by focusing miR-130a-5p/HMGB2 pathway. MiR expression profile was determined and myocardial infarction was induced in cardiomyocytes and rats, which was treated with Pue. The role of miR-130a-5p and downstream HMGB2/NF-κB axis in the cardio-protective effects of Pue was also explored. Pue increased viability and suppressed inflammation in OGD cardiomyocytes, which was associated with the deactivation of HMGB2/NF-κB pathway. After the suppression of miR-130a-5p, the cardio-protective effects of Pue were compromised. In rat models, Pue attenuated structure deterioration and inflammatory response in heart. At the molecular level, miR-130a-5p was up-regulated, and HMGB2 were down-regulated. It was demonstrated that Pue induced the expression of miR-130a-5p, which suppressed the activity of HMGB2/NF-κB, contributing to the attenuation of infarct heart tissues.

Asiaticoside attenuates oxygen-glucose deprivation/reoxygenation-caused injury of cardiomyocytes by inhibiting autophagy

Asiaticoside is a natural triterpene compound derived from Centella asiatica, possessing confirmed cardioprotective property. However, the roles of asiaticoside in regulating oxygen-glucose deprivation/reoxygenation (OGD/R)-caused cardiomyocyte dysfunction remain largely obscure. Human cardiomyocyte AC16 cells were stimulated with OGD/R to mimic myocardial ischemia/reperfusion injury and treated with asiaticoside. Cytotoxicity was investigated by CCK-8 assay and lactate dehydrogenase (LDH) release analysis. Autophagy- and Wnt/β-catenin signaling-related protein levels were measured via western blotting. Asiaticoside (0-20 μM) did not induce cardiomyocyte cytotoxicity. Asiaticoside (20 μM) mitigated OGD/R-induced autophagy, cytotoxicity, oxidative stress, and myocardial injury. Rapamycin, an autophagy inductor, reversed the influences of asiaticoside on autophagy, cytotoxicity, oxidative stress, and myocardial injury, whereas 3-methyadanine, an autophagy inhibitor, played an opposite effect. Asiaticoside (20 μM) attenuated OGD/R-induced Wnt/β-catenin signaling inactivation, which was reversed after transfection with si-β-catenin. Transfection with si-β-catenin attenuated the influences of asiaticoside on autophagy, cytotoxicity, oxidative stress, and myocardial injury. In conclusion, asiaticoside protected against OGD/R-induced cardiomyocyte cytotoxicity, oxidative stress, and myocardial injury via blunting autophagy through activating the Wnt/β-catenin signaling, indicating the therapeutic potential of asiaticoside in myocardial ischemia/reperfusion injury.

Antioxidant Activity of Aqueous Extract of Leaves and Seeds of Datura metel (Solanaceae) in Frog's Heart Failure Model

Objective

The aim of this work was to evaluate the antioxidant potential of Datura metel.

Materials and Methods

Heart failure was induced in the frog's heart by continuous perfusion of hydrogen peroxide. Survival time and some heart tissue parameters of oxidative stress were recorded in the presence of aqueous extracts of the leaves and seeds of Datura metel. Ascorbic acid was used as a reference drug.

Results

H2O2-enriched Ringer's solution inhibited the negative inotropic and chronotropic effects of acetylcholine, indicating the desensibilization of muscarinic receptors due to H2O2-induced oxidative stress. These hearts had a relatively short survival time (14 minutes). In the presence of the aqueous extract of the leaves and seeds of Datura metel (1.5 and 2.5 mg/mL), the time necessary to cause the cardiac arrest was extended to 35 and 37 minutes, respectively, versus 29 minutes for ascorbic acid and 14 minutes for H2O2. Furthermore, antioxidant parameters (MDA, SOD, and CAT) were significantly improved in plant extract-treated hearts, compared to peroxidized hearts.

Conclusion

Aqueous extract of the leaves and seeds of D. metel can extend heart survival time through antioxidant mechanisms.