FIG. 5.

PPP1R3G knockdown slows down postprandial blood glucose clearance in the mouse. A: Knockdown of PPP1R3G in the mouse liver. Male C57BL/6 J mice at 8 weeks of age were infected with shRNA adenovirus as indicated via tail-vein injection. At 15 days post-infection, animals were killed in the fasted state (overnight fasting). Liver proteins were used in immunoblotting with the antibodies as indicated. B: Liver glycogen content was measured from mice as in A after fasting and feeding for the time as indicated. Data are shown as mean ± SD. ***P < 0.001 between groups as indicated. C–E: Glucose tolerance test (for C) and insulin tolerance test (for E) were performed at 4 days post-infection (n = 6 for Ad-Scrambled-shRNA and n = 8 for Ad-PPP1R3G-shRNA). Mice were fasted for 12 h before the test. AUC (for D) was calculated from the glucose tolerance test. Data are shown as mean ± SD. *P < 0.05, **P < 0.01, and ***P < 0.001 between the two groups. F: Postprandial newly synthesized liver glycogen using D-[3-³H]glucose as a tracer was measured with mice at 7 days post-infection (n = 8 for both Ad-Scrambled-shRNA and Ad-PPP1R3G-shRNA groups). Mice were fasted for 12 h and intraperitoneally injected with glucose (2 g/kg body wt) containing trace amount of D-[3-³H]glucose. Mice were killed in 1 h, and liver glycogen was isolated and used in scintillation counting. Data are shown as mean ± SE. **P < 0.01 between the two groups.