LB100 ameliorates nonalcoholic fatty liver disease via the AMPK/Sirt1 pathway

Figure 2 LB100 inhibits serine/threonine protein phosphatase 2A activity, upregulates the expression of proteins involved in fatty acid β-oxidation, downregulates the protein levels of lipogenesis genes, and activates the AMPK/Sirt1 signaling pathway in the liver tissues of high fat diet-fed mice. A: Serine/threonine protein phosphatase 2A (PP2A) activity tested by a commercial assay (upper), protein expression of methylated PP2A and PP2A C subunit (lower) of mouse livers from the four groups; B: Western blot analysis of phosphorylated AMP-activated protein kinase α, phosphorylated AMP-activated protein kinase α, and Sirtuin 1; C: Proteins involved in lipid synthesis, such as fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), sterol regulatory element-binding protein 1 (SREBP1) and stearoyl-CoA desaturase-1 (SCD1); D: Proteins involved in fatty acid β-oxidation, such as peroxisome proliferator-activated receptor α, peroxisome proliferator-activated receptor gamma coactivator-1α, carnitine palmitoyltransferase 1α, uncoupling protein 2, and acyl-CoA oxidase 1; E: Gene expression levels of SREBP1, FAS, ACC1 and SCD1 were determined using real-time PCR. Three independent experiments were analyzed, and the data are presented as the mean ± standard deviation. ^aP < 0.05, ^bP < 0.01 vs standard chow diet mice; ^cP < 0.05, ^dP < 0.01 vs HFD mice. PP2A: Serine/threonine protein phosphatase 2A; P AMPK α: Phosphorylated AMP-activated protein kinase α; Sirt1: Sirtuin 1; FAS: Fatty acid synthase; ACC: Acetyl-CoA carboxylase; SREBP1: Sterol regulatory element-binding protein 1; SCD1: Stearoyl-CoA desaturase-1; PPARα: Peroxisome proliferator-activated receptor α; PGC1α: Peroxisome proliferator-activated receptor gamma coactivator-1α; CPT1α: Carnitine palmitoyltransferase 1α; UCP2: Uncoupling protein 2; ACOX1: Acyl-CoA oxidase 1; SCD: Standard chow diet; HFD: High fat diet.