Fig. 4

FoxO3 gain-of-function aggravates hepatic steatosis in mice fed a high-fat diet. a-d C57BL/6 J male mice (8 weeks old) were fed a high-fat diet and were housed under regular light/dark cycles. On day 5, mice were treated with 2 × 10⁹ plaque forming units of Ad-GFP (n = 8) or Ad-FoxO3 (n = 8) via the tail vein and sacrificed on day 20. a Western blot analysis of liver extracts from adenovirus-injected mice. b Oil red O staining of liver sections from representative livers of mice after an overnight fast. c Intrahepatic triglyceride contents were analyzed in the livers of mice after an overnight fast. d Gene expression analysis by RT-PCR in livers from Ad-GFP-treated mice (white bars) or Ad-FoxO3-treated mice (red bars). e and g Intraperitoneal glucose tolerance tests (IPGTT) and intraperitoneal insulin tolerance tests (IPITT) were performed on day 7 and day 12 respectively after overnight fast. Blood glucose levels were measured in Ad-GFP-treated mice (black line) or Ad-FoxO3-treated mice (red line) before and 15, 30, 60, and 120 min post-injection with 2 g/kg dextrose or 1 U/kg insulin intraperitoneally. f and h Area under the curve (AUC) of blood glucose profiles during IPGTT and IPITT. i Body weight analysis of mice. The data are presented as the mean ± SEM. ^*P < 0.05 versus Ad-GFP; ^**P < 0.01 versus Ad-GFP, ^***P < 0.001 versus Ad-GFP. FoxO1, Forkhead box class O 1; SREBP1c, sterol regulatory-element binding protein 1c; SCD1, stearyl-coenzyme A desaturase 1; FAS, fatty acid synthase; ACC1, acetyl-CoA carboxylase 1; GPAM, glycerol-3-phosphate acyltransferase; DGAT2, diacylglycerol acyltransferase 2; G6pc, glucose-6-phosphatase; Pck1, phosphoenolpyruvate carboxykinase