Mechanism for effect of tanshinone IIA on alleviating cardiomyocyte injury induced by oxygen glucose deprivation.

OBJECTIVES: Tanshinone IIA has a wide range of myocardial protective effects. AK003290 is a long noncoding RNA (lncRNA) that is highly expressed in myocardial tissue, and its expression is down-regulated when myocardial injury occurs. This study aims to explore the mechanism for tanshinone IIA in alleviating myocardial cell damage induced by oxygen glucose deprivation (OGD). METHODS: OGD model was established in rat H9C2 cardiomyocytes. siRNA was transfected to reduce AK003290 expression. H9C2 cells were divided into 6 groups: A control group, a tanshinone IIA (TAN) group, an OGD group, a tanshinone IIA+OGD (TAN+OGD) group, a scrambled siRNA transfection+tanshinone IIA+OGD (scrambled siRNA+TAN+OGD) group, and a AK003290 siRNA transfection+tanshinone IIA+OGD (AK003290 siRNA+TAN+OGD) group. H9C2 cells in the TAN group were treated with 40 μmol/L tanshinone IIA for 12 h. The TAN+OGD group was treated with 40 μmol/L tanshinone IIA for 12 h, followed by OGD treatment for 12 h. The scrambled siRNA+TAN+OGD group and AK003290 siRNA+TAN+OGD group were transfected with the scrambled siRNA or AK003290 siRNA. Twenty-four hours later, the cells were treated with tanshinone IIA and OGD. Real-time RT-PCR was used to detect the expression of AK003290. Spectrophotometry was used to detect the content of lactate dehydrogenase (LDH) in cell culture medium to reflect LDH leakage rate, and enzyme-linked immunosorbent assay (ELISA) was used to detect the content of interleukin-1β (IL-1β) and interleukin-18 (IL-18). Western blotting was used to detect the protein expression of phospho-nuclear factor- κB (p-NF-κB). RESULTS: Compared with the control group, the leakage rate of LDH, the content of IL-1β and IL-18 in culture medium, and the protein expression level of p-NF-κB were increased in the OGD group (P<0.01 or P<0.001). Compared with the OGD group, the leakage rate of LDH, the content of IL-1β and IL-18 in culture medium, and the protein expression level of p-NF-κB were decreased in the TAN+OGD group (P<0.05 or P<0.01). Compared with the control group, the AK003290 expression was increased in the TAN group (P<0.01) and it was decreased in the OGD group (P<0.05). Compared with the OGD group, the AK003290 expression was increased in the TAN+OGD group (P<0.05). Compared with the scrambled siRNA+TAN+OGD group, the leakage rate of LDH, the content of IL-1β and IL-18 in culture medium, and the protein expression level of p-NF-κB were increased in the AK003290 siRNA+TAN+OGD group (P<0.05 or P<0.01). CONCLUSIONS: Tanshinone IIA inhibits NF-κB activity and attenuates OGD-induced inflammatory injury of cardiomyocytes through up-regulating AK003290.