Fig. 5

Injection of a single dose of recombinant mouse IL-22 (rmIL-22) protein reduces blood glucose levels in HFD- and streptozotocin (STZ)-treated mice. a Mice were fed a HFD for 8 weeks and then injected with saline or rmIL-22 for 2 h. Blood glucose levels were detected 120 min post IL-22 injection. b, c C57BL/6 mice were injected with STZ for 5 consecutive days. Twenty eight days later, mice were injected with saline or rmIL-22, and sacrificed 2 h later. Pancreas weights and insulin levels were measured (panel b). Glucose levels were measured at various time points post rmIL-22 injection (panel c). Values represent the mean ± SEM (n = 10). *P < 0.05 and **P < 0.01 compared with the corresponding saline treated groups. d C57BL/6 mice were treated with rmIL-22 for 2 h, pancreas tissues were collected for immunostaining with anti-pSTAT3 antibody. Representative positive pSTAT3 nuclei in acinar cells are indicated by yellow arrows but not in islets (indicated by dotted lines)