Effects of 24R-epimer and 24S-epimer on P-gp expression levels in Caco-2 cells.

<p>Cells were exposed to 24R-epimer or 24S-epimer at concentrations of 1 µM (A) and 10 µM (B), and 1% of DMSO as a solvent control for 48 and 72 h. The bar graphs show the P-gp protein band intensity corrected by that of β-actin.</p

Analytical conditions in LC-MS/MS analysis of 24R-epimer, 24S-epimer and digoxin.

<p>CID, collision induced decomposition voltage; IS, internal standard.</p

Pharmacokinetic parameters of 24R-epimer and 24S-epimer in rat plasma after oral administration and intravenous administration of 24R-epimer or 24S-epimer, respectively.

<p>(n = 5 per group).</p><p>iv, intravenous group; BA, bioavailability.</p

Effects of 24R-epimer and 24S-epimer on the transport of P-gp substrate digoxin across Caco-2 cell monolayers.

<p>Cells were preincubated for 1-epimer (1 and 10 µM) or 24S-epimer (1 and 10 µM), and followed by co-incubation for 2 h in the presence of 5 µM digoxin. Data are the mean ± S.E. of three independent experiments. ^*<i>p</i><0.01 versus control, ^#<i>p</i><0.01 between groups.</p

Effects of 24R-epimer and 24S-epimer on the accumulation of rhodamine 123 in Caco-2 cells.

<p>Cells were preincubated for 1-epimer or 24S-epimer at concentrations of 1, 5 and 10 µM, respectively; and followed by co-incubation for 2 h in the presence of 5 µM rhodamine 123. Data are the mean ± S.E. of three independent experiments. ^*<i>p</i><0.05 versus control; ^**<i>p</i><0.01 versus control.</p

The effect of 24R-epimer and 24S-epimer on Caco-2 cell viability.

<p>Cells were incubated with 24R-epimer or 24S-epimer for 48 h at the concentration range of 1–100 µM, respectively; and the cell viability was measured by MTT assay. Data are the mean ± S.E. of three independent experiments.</p

Plasma concentration-time profiles of 24R-epimer and 24S-epimer in rats.

<p>The intragastric administration groups were administered 24R-epimer (A) or 24S-epimer (B) at doses of 5, 10 and 20 mg/kg, respectively. The intravenous groups were presented in smaller figure administered 1 mg/kg of 24R-epimer or 24S-epimer, respectively. n = 5 per group.</p

The uptake concentration-time profiles of 24R-epimer and 24S-epimer in Caco-2 cells.

<p>24R-epimer and 24S-epimer concentrations: 1, 5 and 20 µM, respectively. Data are the mean ± S.E. of three independent experiments.</p

Proposed possible metabolism pathway of ginsenoside Rg3 and its deglycosylated metabolites.

<p>Proposed possible metabolism pathway of ginsenoside Rg3 and its deglycosylated metabolites.</p

The apparent permeability (P_app) and efflux ratio (ER) of 24R-epimer and 24S-epimer across Caco-2 monolayers.

<p>Data are the mean ± S.E. of three independent experiments.</p