Adiponectin Intervention to Regulate Betatrophin Expression, Attenuate Insulin Resistance and Enhance Glucose Metabolism in Mice and Its Response to Exercise

Figure 1. Effect of adiponectin knockout on betatrophin expression. (A) Plasma concentrations of adiponectin and betatrophin determined using ELISA at the end of the interventions (n = 6–8 in each group). (B) Western blot analysis of adiponectin and betatrophin expression in mouse liver. Data from at least three independent experiments are shown and are expressed as the mean ± standard deviation. Student’s t test: * p < 0.05, ** p < 0.01.

Figure 2. Effect of exercise on adiponectin and betatrophin expression in livers of wild type (CON) and Adipoq−/− mice. (A) Plasma concentrations of adiponectin and betatrophin determined using ELISA at the end of the interventions (n = 6–8 in each group). (B) Western blot analysis of betatrophin expression in the mouse liver. Data from at least three independent experiments are shown, and all data are expressed as the mean ± standard deviation. Student’s t test: * p < 0.05, ** p < 0.01.

Figure 3. Exercise and adiponectin co-intervention reduces betatrophin expression in mouse liver. (A) mRNA levels of Lkb1, Ppargc1a, and Angptl8 were measured using RT-qPCR. All PCRs were performed in at least three independent experiments, in triplicate. (B) Plasma concentrations of adiponectin and betatrophin determined using ELISA at the end of the interventions (n = 6–8 in each group). (C–F) Western blot analysis of LKB1, p-AMPK, PGC-1α, and betatrophin expression (Wild type [CON] and Adipoq−/− mice received an i.p. injection of either Acrp30 [28 µg kg−1 day−1] or saline for 1 week. Data from at least three independent experiments are shown, and all data are expressed as the mean ± standard deviation. Student’s t test: * p < 0.05, ** p < 0.01.

Figure 4. Exercise inhibits betatrophin expression and improves insulin sensitivity in obese mice. Mice fed a high-fat diet (HFD) were randomly allocated to HFD, HFD + Acrp30, HFD + EXE, or HFD + Acrp30 + EXE groups. (A) Body weights of HFD mice in the different intervention groups were recorded at regular intervals. (B) Fasting blood glucose concentration. (C) Serum insulin levels. (D,E) Plasma concentrations of adiponectin and betatrophin determined using ELISA at the end of the interventions (n = 6–8 in each group). (F) mRNA expression levels of Lkb1, Ppargc1a, and Angptl8 in the liver were measured using RT-qPCR. All PCRs were performed in triplicates in at least three independent experiments. (G–J) Western blot analysis of LKB1, p-AMPK, PGC-1α, and betatrophin expression in mouse liver. The HFD+Acrp30+EXE group received an i.p. injection of either Acrp30 (28 µg kg−1 day−1) or saline for the last week of exercise training. Data from at least three independent experiments are shown, and all data are expressed as the mean ± standard deviation. Student’s t test: * p < 0.05, ** p < 0.01, ## p < 0.01.

Figure 5. Schemata of the animal experimental set-up. CON, control; EXE, exercise; WT, wild type; Acrp30, adiponectin; HFD, high-fat diet; Adipoq, mouse adiponectin gene; Adipoq−/−, adiponectin gene knockout mice.