Fig. 2

Detection of glucose metabolic parameters and hippocampal insulin signaling pathway. No statistical difference was discovered among the five groups in IPGTT results (a, b). As for ITT, it presented that CUMS mice got larger AUC than that of the control group, while the AUC of CUMS + Glb group was smaller as compared to that of CUMS + Veh (c, d) (^# p < 0.05 vs. Control, ^** p < 0.01 vs. CUMS + Veh). In GSIS test, it showed that before the injection of glucose, CUMS and CUMS + Veh mice got higher levels of plasma insulin; besides, 30 min after glucose administration, non-stressed control but not stressed mice showed a significant increase of plasma insulin (e) (^# p < 0.05, ^* p < 0.05). Although not significantly enough, there existed a rising trend of HOMA-IR index in stressed mice, especially that of CUMS and CUMS + Veh groups as compared with Control mice (f). In comparison, CUMS and CUMS + Veh mice presented more phosphorylation of IRS(Ser307) and less phosphorylation of AKT(Ser473) in hippocampi than that of Control, remarkably, CUMS + Glb reversed those changes meaningfully (g–i) (^# p < 0.05, ^## p < 0.01, ^### p < 0.001 vs. Control, ^* p < 0.05 vs. CUMS + Veh). Data presented as mean ± SEM, n = 6 for a–f, n = 4 for g–i