Figure 5. Phloretin restoring SIRT1 to inhibit hyperglycemia-induced inflammation and fibrosis in H9C2 cells. (A) The cytotoxicity of PHL in H9C2 cell. (B-C) H9C2 (1*10^6) cells were pre-treated with PHL (20 μM) for 1 h and then incubated with HG (33 mM) for 24 h. The cell lysates were immunoblotted for SIRT1, with GAPDH as a loading control. (D-H) H9C2 cells pre-treated with PHL for 1 h were stimulated by HG (33 mM). Total RNAs were extracted and the mRNA levels of IL-6 and TNF-α in 12 h (D-E) or ANP, COL-1A1 and TGF-β (F-H) in 36 h were detected by RT-qPCR. Data are presented as means ± SEM. *P < 0.05, **P < 0.01 v.s. HG group; #P < 0.05, ##P < 0.01 v.s. DMSO group.