Background
Myocardial ischemia is the main reason for ischemic heart disease. Baicalin is a plant-derived flavonoid with cardio-protective activity. Herein, we tested the influences of baicalin on cardiomyocytes H9c2 apoptosis aroused by hypoxia stimulation.
Conclusion
Baicalin relieved cardiomyocytes H9c2 apoptosis aroused by hypoxia might be achieved through activating Nrf2/HO-1-mediated HIF1α/BNIP3 pathway. Highlights Baicalin mitigates H9c2 cell viability loss and apoptosis aroused by hypoxia; Baicalin activates HIF1a/BNIP3 pathway in hypoxia-exposed H9c2 cells; Silencing HIF1α weakens the influences of baicalin on hypoxia-exposed H9c2 cells; Baicalin promotes Nrf2/HO-1 pathway in hypoxia-exposed H9c2 cells; Promotion of Nrf2/HO-1 pathway is related to the up-regulation of HIF1α.
Methods
Firstly, H9c2 cells were subjected to hypoxia and/or baicalin exposure. Cell viability and apoptosis, along with hypoxia-inducible factor 1α (HIF1α) and Bcl-2/adenovirus E1B 19-KDa interacting protein 3 (BNIP3) expressions were tested respectively. Then, si-HIF1α was transfected into H9c2 cells to probe whether up-regulation of HIF1α attended to the influences of baicalin on hypoxia-stimulated H9c2 cells. Finally, the regulatory effect of nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway on HIF1α expression was analyzed.
Results
Hypoxia exposure aroused H9c2 cell viability reduction and apoptosis. Baicalin mitigated H9c2 cell viability reduction and apoptosis aroused by hypoxia. Moreover, HIF1α/BNIP3 pathway was further activated by baicalin in hypoxia-exposed H9c2 cells. Silencing HIF1α lowered the functions of baicalin on hypoxia-exposed H9c2 cells. Besides, baicalin enhanced hypoxia-caused activation of Nrf2/HO-1 pathway. Activation of Nrf2/HO-1 pathway was associated with the up-regulation of HIF1α and protective functions of baicalin on hypoxia-exposed H9c2 cells.