Figure 1.
Effects of compounds on body weight and fasting glucose levels in db/db mice. Male C57BLKS/J db/db and db/m diabetic mice were left untreated or orally treated with metformin at 150 mg/kg, BB at 200 mg/kg, or BB at 200 mg/kg plus OPCs at 60 mg/kg, respectively. After treatment for 4 weeks, body weight (a) and fasting glucose (b) levels were measured. Data are presented as mean ± SEM of eight mice in each group. ** p < 0.01, *** p < 0.001 vs. untreated control.
Figure 1.
Effects of compounds on body weight and fasting glucose levels in db/db mice. Male C57BLKS/J db/db and db/m diabetic mice were left untreated or orally treated with metformin at 150 mg/kg, BB at 200 mg/kg, or BB at 200 mg/kg plus OPCs at 60 mg/kg, respectively. After treatment for 4 weeks, body weight (a) and fasting glucose (b) levels were measured. Data are presented as mean ± SEM of eight mice in each group. ** p < 0.01, *** p < 0.001 vs. untreated control.
Figure 2.
Effects of the 5 weeks administration of compounds in the (a) OGTT and (c) IPTT in db/db mice with diabetes. (a) After 14 h of fasting, 0.35 g of glucose per kilogram of body weight was gavaged into mice and calculated as 0 min. Blood glucose levels were measured at the indicated times shown in the graph. (c) After 6 h of fasting, blood glucose concentrations were measured at the indicated time following intraperitoneal injection of 1 IU of insulin per kilogram of body weight. AUCs for (b) OGTT and (d) IPTT are shown in the graph. Data are presented as mean ± SEM of eight mice in each group. *** p < 0.001 vs. untreated control.
Figure 2.
Effects of the 5 weeks administration of compounds in the (a) OGTT and (c) IPTT in db/db mice with diabetes. (a) After 14 h of fasting, 0.35 g of glucose per kilogram of body weight was gavaged into mice and calculated as 0 min. Blood glucose levels were measured at the indicated times shown in the graph. (c) After 6 h of fasting, blood glucose concentrations were measured at the indicated time following intraperitoneal injection of 1 IU of insulin per kilogram of body weight. AUCs for (b) OGTT and (d) IPTT are shown in the graph. Data are presented as mean ± SEM of eight mice in each group. *** p < 0.001 vs. untreated control.
Figure 3.
Effects of compounds on ALT, AST, TC, TG levels in db/db mice. The db/db mice were treated with the vehicle, 150 mg/kg of metformin, 200 mg/kg of BB and 200 mg/kg of BB plus 60 mg/kg of OPCs for 5 weeks. Then, the (a) ALT in the plasma. (b) AST in the plasma. (c) TC in the plasma. (d) TG in the plasma were measured. Data are presented as mean ± SEM of eight mice in each group. *** p < 0.001 vs. untreated control.
Figure 3.
Effects of compounds on ALT, AST, TC, TG levels in db/db mice. The db/db mice were treated with the vehicle, 150 mg/kg of metformin, 200 mg/kg of BB and 200 mg/kg of BB plus 60 mg/kg of OPCs for 5 weeks. Then, the (a) ALT in the plasma. (b) AST in the plasma. (c) TC in the plasma. (d) TG in the plasma were measured. Data are presented as mean ± SEM of eight mice in each group. *** p < 0.001 vs. untreated control.
Figure 4.
Cytotoxicity and reversing activity of BB and OPCs by MTT assay in Caco-2 cells. Cells were treated with various concentrations of BB (a) and OPCs (b) for 24 h for toxic determination. Data are presented as mean ± SEM of three independent experiments. *** p < 0.001 vs. control.
Figure 4.
Cytotoxicity and reversing activity of BB and OPCs by MTT assay in Caco-2 cells. Cells were treated with various concentrations of BB (a) and OPCs (b) for 24 h for toxic determination. Data are presented as mean ± SEM of three independent experiments. *** p < 0.001 vs. control.
Figure 5.
The effects of OPCs on R123 accumulation in Caco-2 cells were investigated at 108 mg/L. Verapamil (100 μM) was used as positive control. Data are presented as mean ± SEM of three independent experiments. ** p < 0.01, *** p < 0.001 vs. control.
Figure 5.
The effects of OPCs on R123 accumulation in Caco-2 cells were investigated at 108 mg/L. Verapamil (100 μM) was used as positive control. Data are presented as mean ± SEM of three independent experiments. ** p < 0.01, *** p < 0.001 vs. control.
Figure 6.
OPCs increased the uptake of BB in Caco-2 Cells. Caco-2 intestinal cells were treated with 25 μM of BB and BB with OPCs at 108 mg/L for different time (a) or BB with OPCs at 54 mg/L or 108 mg/L for 2 h (b). Verapamil (100 μM) was used as positive control, cells were harvested for determination of the uptake of BB. Quantities of BB in the cells were determined by LC–MS/MS. Data are presented as mean ± SEM of three independent experiments. * p < 0.05, ** p < 0.01, *** p < 0.001 vs. control (BB alone), # p < 0.05 108 mg/L of OPCs vs. verapamil.
Figure 6.
OPCs increased the uptake of BB in Caco-2 Cells. Caco-2 intestinal cells were treated with 25 μM of BB and BB with OPCs at 108 mg/L for different time (a) or BB with OPCs at 54 mg/L or 108 mg/L for 2 h (b). Verapamil (100 μM) was used as positive control, cells were harvested for determination of the uptake of BB. Quantities of BB in the cells were determined by LC–MS/MS. Data are presented as mean ± SEM of three independent experiments. * p < 0.05, ** p < 0.01, *** p < 0.001 vs. control (BB alone), # p < 0.05 108 mg/L of OPCs vs. verapamil.
Figure 7.
Effects of OPCs and verapamil on the apparent permeability (Papp) of BB across Caco-2 monolayers. The apical to basolateral permeability values PappA-B and basolateral to apical permeability values PappB-A were determined as the slope of the linear portion of each transport-time profile. Data are presented as mean ± SEM of three independent experiments with 2 transwell inserts each. *** p < 0.001 vs. control (BB alone).
Figure 7.
Effects of OPCs and verapamil on the apparent permeability (Papp) of BB across Caco-2 monolayers. The apical to basolateral permeability values PappA-B and basolateral to apical permeability values PappB-A were determined as the slope of the linear portion of each transport-time profile. Data are presented as mean ± SEM of three independent experiments with 2 transwell inserts each. *** p < 0.001 vs. control (BB alone).
Figure 8.
Effect of OPCs with different concentrations on P-gp expression for 24 h by Western blot. Representative blots were presented in the upper panel (a). Blots were scanned and quantified; the level of P-gp was normalized to that of β-Actin (ACTB) and plotted as percent of DMSO (b), which was designated as 100%. The quantitative data in histogram are presented as mean ± SEM of three independent experiments. ** p < 0.01 vs. control (DMSO).
Figure 8.
Effect of OPCs with different concentrations on P-gp expression for 24 h by Western blot. Representative blots were presented in the upper panel (a). Blots were scanned and quantified; the level of P-gp was normalized to that of β-Actin (ACTB) and plotted as percent of DMSO (b), which was designated as 100%. The quantitative data in histogram are presented as mean ± SEM of three independent experiments. ** p < 0.01 vs. control (DMSO).
Figure 9.
Pharmacokinetic Study. Male SD mice were orally administered with BB alone at 200 mg/kg, or 200 mg/kg of BB plus 120 mg/kg of OPCs, respectively. Blood samples were taken at 0, 0.083, 0.25, 0.5, 0.75, 1, 2, 4, 6, 8, 12, and 24 h after administration. Plasma concentrations of BB were determined by LC–MS/MS and plotted against time. Data are presented as mean ± SEM of six animals in each group. * p < 0.05 vs. that of the same time point.
Figure 9.
Pharmacokinetic Study. Male SD mice were orally administered with BB alone at 200 mg/kg, or 200 mg/kg of BB plus 120 mg/kg of OPCs, respectively. Blood samples were taken at 0, 0.083, 0.25, 0.5, 0.75, 1, 2, 4, 6, 8, 12, and 24 h after administration. Plasma concentrations of BB were determined by LC–MS/MS and plotted against time. Data are presented as mean ± SEM of six animals in each group. * p < 0.05 vs. that of the same time point.
Figure 10.
RP-HPLC chromatographic profile of OPCs detected at 280 nm. Peak 1 was A-type tetramer cassiatannin A, peaks 2 and 3 were A-type trimers, cinnamtannin D1 and cinnamtannin B1, respectively.
Figure 10.
RP-HPLC chromatographic profile of OPCs detected at 280 nm. Peak 1 was A-type tetramer cassiatannin A, peaks 2 and 3 were A-type trimers, cinnamtannin D1 and cinnamtannin B1, respectively.
Table 1.
Effects of drugs on the transport of BB across Caco-2 cell monolayers.
Table 1.
Effects of drugs on the transport of BB across Caco-2 cell monolayers.
| Papp(A-B, ×10−6) | Papp(B-A, ×10−6) | R = Papp(B-A)/Papp(A-B) |
---|
BB | 0.146 ± 0.012 | 1.001 ± 0.049 | 7.74 ± 1.13 |
BB + VER | 0.337 ± 0.040 *** | 0.654 ± 0.020 *** | 2.23 ± 0.41 *** |
BB + OPCs | 0.137 ± 0.021 | 0.489 ± 0.030 *** | 4.10 ± 0.78 ** |