Figure 1.

ANRIL upregulates SIRT1 expression following H/R injury. (A-C) H9c2 cardiomyocytes were cultured under a normoxic condition (normoxia) or exposed to hypoxia for 4 h followed by reoxygenation (H/R) for 2 to 24 h, as indicated. (A) ANRIL and (B) SIRT1 mRNA expression levels were determined by reverse transcription-quantitative PCR analysis. β-actin served as an internal control. Results are expressed as relative to the normoxia group. (C) SIRT1 protein expression was detected by an immunoblotting assay. β-actin served as a loading control. Results are representative of three independent experiments. (D-G) H9c2 cardiomyocytes were transiently transfected with pcDNA3.1-vector or pcDNA3.1-ANRIL plasmids (1, 2 or 4 µg per well). At 2 days after transfection, cells were cultured under normoxia or exposed to H/R (4 h hypoxia followed by 8 h reoxygenation) as indicated. The expression of (D) ANRIL following transfection was detection. (E) ANRIL and (F) SIRT1 mRNA expression levels, and (G) SIRT1 protein expression were determined. Data are presented as the mean ± SD. n=3. **P<0.01 vs. control group. NS, not significant; ANRIL, antisense non-coding RNA in the INK4 locus; SIRT1, sirtuin 1; H/R, hypoxia/reoxygenation.