Fig. 6

LMY reduces hepatic lipid accumulation in a FOXM1-dependent manner via Yap1 activity(A) Typical oil red O staining images showing the alleviation of lipid accumulation in LMY cells treated with or without FOXM1 inhibitors (RCM-1 and Thiostrepton). The numbers in each image refer to the number of fish in each treatment group. (B) Quantification of the alleviating effect of LMY on lipid accumulation in the presence or absence of FOXM1 inhibitors. The average oil red O staining intensity of HCF-fed zebrafish treated with DMSO was defined as 100%. (C) GSEA curve of genes associated with the Hippo signaling pathway. (D) Heatmap of the DEGs within the Hippo and FOXM1 signaling pathways. All these experiments were conducted three times in a double-blind manner, and the quantification results are presented as the mean±SEM. *P<0.05, **P <0.01, ***P<0.001, and ****P<0.0001. ns, no significance. LMY ameliorates lipid accumulation through the inhibition of Yap1 activity Interestingly, FOXM1 activation is closely related to Yap1, and Yap1 was also recently proven to stimulate lipid synthesis [57]; therefore, we further investigated whether Yap1 is involved in the therapeutic effect of LMY on NAFLD. The results demonstrated that the expression of Hippo pathway genes was significantly reduced in the livers of LMY-treated zebrafish according to the GSEA results (Figure 6C,D). To investigate the importance of Yap1 in the therapeutic effect of LMY on NAFLD, the Yap1 inhibitor verteporfin was used to block the activation of Yap1. The results demonstrated that LMY significantly reduced hepatic lipids, while the therapeutic effect of LMY was not significant in the presence of verteporfin (Figure 7A,B), indicating that Yap1 activity is vital for the hepatic lipid-reducing effect of LMY.