Fig. 5

STAT3 involved in the downregulation of NPC1L1 by diosgenin. A Heatmap show of differentially expressed genes found in RNA-Seq between diosgenin treated Caco2 cells and the control cells. B Bubble chart of differentially expressed genes KEGG enrichment. C Venn diagram demonstrated the intersections of genes between differentially expressed genes and STAT3 target genes. D Predicted 3D structures of STAT3 protein in interaction with diosgenin. E The effect of IL6 and diosgenin on STAT3 phosphorylation. F The NPC1L1 promoter activity was measured by firefly luciferase activity and normalized by renilla luciferase activity. STAT3 overexpression plasmid was induced to enhance the NPC1L1 promoter activity. G Analysis of Chromatin immunoprecipitations (CHIP)-Seq data of STAT3 from published database. The peaks ahead of NPC1L1 RefSeq referrred to enrichment of STAT3 target sequence. H CHIP assay was performed with IL6 treated in Caco2 cells. The enriched DNA was quantified by real-time PCR. Human c-Fos promoter was used as positive control. The result was represented as signal relative to the total amount of input chromatin and adjusted by IgG group which was equivalent to one. I Intestinal STAT3 phosphorylation of DG gavage mice compared to control group by Western blot. The gray value ratio was plotted on the side. J The mRNA expression of STAT3 downstream gene c-Fos in small intestine from DG gavage mice compared to that from the control group. Data are expressed as mean ± SEM (n = 5 in each group). *P < 0.05, ****P < 0.0001