Fig. 7

Norharman promoted Rftn1 transcription by inhibiting the enzymatic activity of HDACs to increase H3K9/14 acetylation. A, B Norharman significantly increased Rftn1 mRNA and protein expression by qPCR and western blot (n = 5). C Norharman did not bind directly to the Rftn1 promoter region, as verified by a dual-luciferase reporter assay (n = 6). D Norharman significantly inhibited the enzymatic activity of HDAC1-4 by measuring the enzymatic activity of HDAC1-4 (n = 4). E The detailed 3D binding mode of HDAC1-4 with norharman by molecular docking analysis. The compound is colored yellow, the surrounding residues in the binding pockets are colored cyan, and the backbone of the receptor is depicted as a slate cartoon. The hydrogen bonds are depicted as yellow dashed lines. F The Rftn1 promoter region (− 2000/ + 500) was truncated into 9 segments. G, H Norharman increased active H3K9/14Ac signals at the Rftn1 promoter by ChIP assay (n = 4). Data are presented as the mean ± SEM; *P < 0.05 and **P < 0.01 vs. the IgG (LPS), Ctrl or LPS group; ^#P < 0.05 and ^##P < 0.01 vs. the IgG (LPS + Nor) group; ^&P < 0.05 and ^&&P < 0.01 vs. the LPS group