Figure 4

Intra-peritoneal glucose (IPGTT), insulin levels and intra-peritoneal insulin tolerance tests (IPITT) in chow-fed mice. (a) IPGTT was performed on WT and transgenic mice at 2, 7, 10 and 12 months of age (n = 25 WT and 25 Tg^sAnk1.5/+; 22 WT and 24 Tg^sAnk1.5/+; 25 WT and 25 Tg^sAnk1.5/+; 15 WT and 16 Tg^sAnk1.5/+, respectively). Mice were fasted overnight for 17 h, and glucose (2 g/kg) was administered through intraperitoneal injection. Blood glucose concentration was measured at 0, 30-, 60-, 120-, and 180-min following injection. (b) AUC ± SD calculated from glycemic curves reported in (a). (c) Serum insulin levels (ng/ml ± SD) in WT and Tg^sAnk1.5/+ mice following 17 h of fasting, and 15 and 60 min after glucose administration (2 g/kg). (d) IPITT was performed on 12-month-old WT and transgenic mice. Mice were fasted daily for 5 h, and insulin (1 U/kg) was administered through intraperitoneal injection. Blood glucose concentration was measured at 0, 15-, 30-, 60-, 90-, and 120 min following injection. e: AUC ± SD calculated from glycemic curves reported in (d). (f) Western blot analyses of AKT phosphorylation at serine 473 in the gastrocnemius muscle from WT and Tg^sAnk1.5/+ mice. (g) Densitometric analysis of p-AKT^Ser473, p-AKT^Thr308 (see also Supplementary Fig. S2 online) and total AKT, using actin (ponceau S staining) as a normalizer, is expressed as fold levels of pAKT/totalAKT ratio ± SD, relative to WT mice. *p < 0.01, Student’s t-test. Original blots/gels are reported in Supplementary Fig. S2 online.