Salidroside Inhibits HMGB1 Acetylation and Release through Upregulation of SirT1 during Inflammation

Figure 8

Salidroside reverses LPS-induced HMGB1 acetylation and nucleocytoplasmic translocation in SirT1 shRNA-transfected RAW264.7 cells. The cells were transfected with SirT1shRNA and control plasmids for 48 h; after the transfection, cells were pretreated with salidroside for 2 h and then treated with LPS for 12 h. (a) Nuclear and cytoplasmic and total protein were extracted, respectively; the levels of HMGB1 were detected by Western blotting. The histogram showed the relative expression of HMGB1 in nuclear and cytoplasmic protein normalized to lamin B1 or GAPDH, respectively. The experiments were done three times, and data were shown as mean ± SD. compared with the group stimulated without LPS in control plasmid-transfected cells. compared with the group stimulated with LPS in control plasmid-transfected cells. compared with the group stimulated without LPS in SirT1 shRNA-transfected cells. compared with the group stimulated with LPS in SirT1 shRNA-transfected cells. compared with the group stimulated with LPS in SirT1 shRNA-transfected cells. The localization of HMGB1 was visualized by confocal microscopy. (b) The cells were transfected with control plasmids and SirT1 shRNA plasmids; after 48 h transfection, cells were pretreated with salidroside for 2 h and then stimulated with LPS for another 4 h. HMGB1 acetylation was determined by IP. (c) The histogram showed the relative expression of acetylated HMGB1 normalized to total HMGB1. The experiments were done in triplicate, and data were shown as mean ± SD. compared with the group stimulated without LPS in control plasmid-transfected cells. compared with the group stimulated with LPS in control plasmid-transfected cells. compared with the group stimulated without LPS in SirT1 shRNA-transfected cells. compared with the group stimulated with LPS in SirT1 shRNA-transfected cells.

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