Hyperoside protects against hypoxia/reoxygenation induced injury in cardiomyocytes by suppressing the Bnip3...

Role of hyperoside in protecting cardiomyocytes from ischemia/reperfusion induced injury has been proved. However, possible protecting mechanisms remain unclear. To fix the problem, an essential pro-apoptotic protein Bnip3 was studied in our experiments.

Neonatal rat cardiomyocytes were used and submitted to hypoxia for 8h followed by reoxygenation for 2h to simulate the ischemia/reperfusion injury. Hypoxia/reoxygenation(H/R) induced damage to cardiomyocytes and the protective effect of hyperoside were examined by means of MTT assay. H/R-induced apoptosis was assessed by Terminal-deoxynucleoitidyl Transferase Mediated Nick End Labeling(TUNEL) and DNA Ladder assay. mRNA expression of Bnip3 was determined by use of quantitative real-time reverse transcription polymerase chain reaction assay. Protein levels of Bnip3, Bax, Bcl-2 and cleaved caspase-3 were examined using western-blot assay. Our results showed that H/R caused great damage to cardiomyocytes, upregulated the protein expressions of Bnip3, Bax, cleaved caspase3, and decreased the expression of the anti-apoptotic protein of Bcl-2. Whereas, compared with the H/R group, a decrease in activities of Bnip3, Bax, cleaved caspase3, and a promoting expression of Bcl-2 were detected in the H/R goup pretreated with hyperoside.

It was concluded in our study that H/R-induced apoptotic effect in cardiomyocytes could be attenuated by hyperoside, and the protective role of hyperoside, if not completely, could be partly through the suppression of the pro-apoptotic gene Bnip3.