Journal: JHEP Reports
Article Title: FGF1 ameliorates hepatic steatosis through acute activation of the unfolded protein response and VLDL production
doi: 10.1016/j.jhepr.2025.101660
Figure Lengend Snippet: FGF1 hyperactivates the UPR in the liver and hepatocytes. (A) Hepatic protein levels of the three UPR branch markers XBP1s, ATF6 (ATF6-U: unspliced & ATF6-N nuclear) and Perk phosphorylation 14 h after FGF1 injection of ob/ob showing UPR activation. In addition, XBP1s and ATF6 in nuclear extracts from these livers. (B) Hepatic expression levels of UPR chaperones ( Grp78 , Erp72 , Erdj3 , Grp94 , and Pdi ), ER-associated protein degradation genes ( Edem and Herp ), and PERK–ATF4–CHOP pathway genes ( Chop and Gadd34 ) in ob/ob mouse liver (Mann-Whitney U test; ∗ p < 0.05, ∗∗ p < 0.01). (C) Hepatic protein levels of Grp78, Grp94, Erp72, Erp57, Pdi and Chop 14 h after FGF1 injection of ob/ob mice. (D) Effect of 3 or 6 h FGF1 on UPR sensors in glucosamine-stressed HepG2 cells, showing Xbp1 mRNA (uXBP1: unspliced & sXBP: spliced), Ire1 and Perk phosphorylation, XBP1s and Atf6 protein levels (unspliced & nuclear) (E) Hyperactivation of UPR chaperone expression levels but not ERAD genes by 6 h FGF1 treatment in glucosamine-stressed (2 h) primary rat hepatocytes. ∗ p < 0.05 glucosamine vs. control, # p < 0.05 glucosamine vs. glucosamine + FGF1 (Kruskal-Wallis test). (F) UPR chaperone protein induction after FGF1 treatment in HepG2 cells with and without glucosamine pre-treatment. UPR, unfolded protein response.
Article Snippet: Mice were treated with vehicle (PBS), recombinant FGF1 (0.5 mg/kg, R&D Systems) or the FGF1 K133E variant (kind gift by Birgitte Andersen, Novo Nordisk, Bagsværd Denmark) by intraperitoneal (i.p.) injection.
Techniques: Phospho-proteomics, Injection, Activation Assay, Expressing, MANN-WHITNEY, Control