Fig. 3

Serum glucose levels and area under the curve of glucose and insulin during oral glucose tolerance test (OGTT). Control, OVX rats fed a high-fat diet with 2 % dextrin; APP, OVX rats fed a high fat diet with 2 % Artemisia princeps Pamp water extract; LJH, OVX rats fed a high fat diet with 2 % Leonurus japonicas Houtt water extract; GJE, OVX rats fed a high fat diet with 2 % Gardenia jasminoides Ellis water extract; positive-control, OVX rats fed a high fat diet with 30 μg/kg body weight 17β-estradiol + 2 % dextrose. At 7th week, an OGTT was conducted in overnight-fasted animals by orally administering 2 g glucose/kg body weight. After glucose loading, blood samples were taken by tail bleeding at 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 120 min to measure serum glucose levels (a) and serum insulin levels were measured at 0, 20, 40, 60, 90 and 120 min (c). Serum glucose levels had significant time and treatment effects but not interaction effects (P < 0.05) in two-way repeated measures ANOVA whereas serum insulin levels exhibited significant effect of time and treatment effects and their interaction effect (P < 0.05). During OGTT area under the curve (AUC) of serum glucose (b) and insulin (d) in the first part (0–40 min), second part (40–120 min) and total parts were given. Bars or dots and error bars represent means ± SD (n = 12). ^a,b,c Significantly different among all groups by Tukey’s test at p < 0.05