2.4.2 ∣. Intraperitoneal glucose tolerance test (IPGTT)

Beginning at 12-weeks-of-age, IPGTTs were performed by an expert technician blinded to the experimental group of each mouse every 4 weeks until and 28-weeks-of-age, and again at 39 weeks (ie, end of life). In line with optimal conditions for assessing glucose tolerance,²² mice were fasted for 6 h during the light cycle (0800-1300) on alpha-dri bedding with ad libitum access to water. IPGTTs were performed by an expert technician blinded to the experimental group of each mouse. Baseline (t = 0-min) blood glucose levels were obtained by tail snip from conscious unrestrained mice using a hand-held glucometer (ReliOn). Subsequently, the mice received an IP injection of 20% dextrose (2 g/Kg body weight) and blood glucose levels were measured at t = 15-, 30-, 60-, and 120-minutes post-injection.