Fig. 1

Anti-viral and anti-inflammatory effects of acetylshikonin in vivo and in vitro. a The binding mode of acetylshikonin with PL pro (PDBID: 7LBR) predicted by the Autodock VINA program. Acetylshikonin is represented as a purple stick, while PL pro is represented as a ribbon diagram. The key residues interacting with the acetylshikonin are shown in line. b The affinity between acetylshikonin and PL pro. c Inhibitory rate of different concentrations of acetylshikonin on PL pro. d RAW264.7, BMDM and lung single cells were induced with poly (I:C) (16 µg/mL) and treated with different concentrations of acetylshikonin (0, 0.6, 1.25, 2.5 μM) for 12 h. The concentration of IL-6 in the cell supernatant was then quantified by ELISA assay. Data represented the concentration of IL-6. e The effect of acetylshikonin on NF-κB signaling in RAW264.7 cells was assessed by Western blot analysis followed by densitometric quantification. The cells were treated with poly (I:C) (16 µg/ml) and 0, 0.6, 1.25 or 5 μM acetylshikonin and harvested at 24 h and 48 h. Cell lysates were then subjected to Western blotting. The results showed the expression of phosphorylated P38 and phosphorylated NF-κB upon treatment with acetylshikonin. f Effect on the nuclear translocation of p-NF-κB and p-P38. Cells were treated with poly (I:C) (16 µg/ml) and different concentrations of acetylshikonin. g The concentrations of IL-6, TNF-α and IL-1α with 300 mg/kg acetylshikonin and 15 mg/kg anti-IL-6 mAb in an acute lung injury mouse model. h H&E staining of lung tissues. (magnification: ×40 m, ×100 m). i The binding of acetylshikonin with endogenous PRDX1 present in RAW264.7 cell lysate was determined via ex vivo pull down assay using Sepharose 4B and acetylshikonin-conjugated Sepharose 4B beads. j The expression of PRDX1 in RAW264.7 cells expressing shRNA-PRDX1 was evaluated by Western blotting. k The concentration of IL-6 and TNF-α with poly (I:C) in RAW264.7 by shRNA silencing of PRDX1. ns. Not significant; *. P ≤ 0.05; **. P ≤ 0.01; ***. P ≤ 0.001