Fig. 7: IL-12 regulates the IRS/FoxO1/FGF21 pathway in the liver.

Liver and plasma samples and primary hepatocytes were isolated from male WT mice (C57BL/6J) treated with IL-12 (0.25 µg/hour) or saline (C, Control) for molecular analyses. A Liver IRS-2 protein levels measured using Jess Multiplexed Western Blot System (n = 3 Controls and 4 IL12-treated mice). B RT-qPCR analysis of IRS-2, FoxO1, and protein-tyrosine phosphatase SHP1 (Ptpn6) mRNA levels in the liver. (n = 3 per group) C Liver FoxO1 protein levels measured using Jess Western Blot System. (n = 4 Controls and 5 IL12-treated mice). D-F Primary hepatocytes were isolated from male WT mice at 4 ~ 5 months of age following a 4-hour intravenous infusion of IL-12 (0.25 µg/hour; n = 4) or saline (Control; n = 4) for RT-qPCR analysis of IRS-2, FoxO1, and fibroblast growth factor 21 (FGF21). mRNA levels were normalized to HPRT and shown relative to controls. G Plasma FGF21 levels using ELISA. (n = 4 per group). H & I Liver samples were collected from male Lyz-IFNγR2^−/− and WT mice after 20 weeks of CDAHFD or GAN diet for RT-qPCR analysis of IRS-1, IRS-2, FoxO1, and FGF21 mRNA levels in the liver. (n = 4 per genotype for CDAHFD-fed mice and n = 5 per genotype for GAN diet-fed mice). J Plasma FGF21 levels were measured using ELISA in male Lyz-IFNγR2^−/− and WT mice after 12 and 20 weeks of the GAN diet. (n = 3 ~ 5 WT and 5 Lyz-IFNγR2^−/− mice) All protein levels were normalized to β-actin as a loading control. All mRNA levels were normalized to HPRT as a housekeeping gene and shown relative to controls. Data are presented as mean ± SEM values. The statistical significance of the difference in mean values was determined using a two-tailed Student’s t-test.