ABSTRACT
To study the metabolic products of main compounds of Chuankezhi injection in rat, 12 Sprague Dawley rats were classed into 2 groups, a blank control group and an intermuscular administration group, respectively. Rat feces and urine samples were collected from 0-24 h and 24-48 h after administration. All the samples were ultrasonically treated with methanol and then analyzed using LC-LTQ Orbitrap MSn. By comparison with the total ion chromatogram of samples from the blank control group, the metabolites in the samples of drug-treated group were screened. These metabolites were further analyzed by multistage product ion scanning and comparison of retention time with reference substances. As a result, a total of 12 flavonoid metabolites were tentatively identified from the rat feces and no metabolite was discovered in the rat urine. Epimedin C and icariin were detected in the rat blood samples after 30 min of administration, but their metabolites and other original flavones were not detected. Furthermore, no original flavones and their metabolites were detected in rat blood samples after 2 and 4 h of administration. The potential metabolism paths were further characterized and the principal in vivo transformation of flavones from Chuankezhi injection were deglycosylation, dehydration, methylation, oxidation and isomerization in rats.
ABSTRACT
A quantitative method for epimedin A, B, C and icariin in rat plasma was established using LC-MS/MS after intermuscular administration of Chuankezhi injection to rat. Chromatographic separation was performed on an Agilent Eclipse XDB-C18 column (150 mm×2.1 mm, 5.0 μm) at 40℃. Mobile phase consisted of acetonitrile -0.1% formic acid in water (35:65), and the flow rate was 0.22 mL·min-1. The LC effluent was detected and analyzed using an ESI-triple quadrupole tandem mass spectrometer under the multiple reaction monitoring (MRM) in the negative ion mode. The plasma samples were treated with solid phase extraction prior to LC-MS/MS analysis. As a result, all of the four analytes displayed a good linearity over the concentration of 1-1000 ng·mL-1. The RSDs of intra-day and inter-day assays were less than 5.99% and 10.16%, respectively. The relative recovery of each analyte was between 88.1%-101.1% with RSD<7.9% and the absolute recovery was between 72.0%-86.6% (RSD<6.3%). In conclusion, the established method shows good specificity, sensitivity and efficiency for quantifying the four flavonoid glycosides contained in rat plasma.
ABSTRACT
To study pharmacokinetic characteristics of epimedin A, B, C and icariin after intermuscular administration of Chuankezhi injection to rat. The established RRLC-MS/MS method was applied for simultaneous determination of four analytes in rat plasma and calculating their pharmacokinetic parameters. As a result, each analyte showed a good linear relationship in the concentration range of 1-1 000 μg•L⁻¹.The intra-day precise was 96.9%-107.5% with RSD<5.99%, inter-day precise was 92.3%-105.0% with RSD<10.16%. The relative recovery of four analytes was 88.1%-101.1% with RSD<7.9% and their absolute recovery was 72.0%-86.6% with RSD<6.3%. After intermuscular administration of Chuankezhi injection, the plasma concentration of four flavonoid glycosides rapidly arose to peaks at about 10 min, and then quickly declined in rat. Tmax of epimedin A, B, C and icariin was 0.21, 0.19, 0.16 and 0.49 h, respectively, and their mean elimination half-life(t1/2z) was 0.60, 0.62, 0.47 and 0.49 h. The established method was validated to be sensitive, rapid and specific for determination of the four analytes. Serum concentration of 4 species of epimedium flavonoids in Chuankezhi injection was low, and their absorption and elimination seem quickly, displaying similar pharmacokinetic characteristics in this study.
ABSTRACT
Objective To explore the synergistic effects of substrate stiffness and cytokine TGF-β1 on phenotypic transformation of hepatocytes by establishing an in vitro culture model with the substrate stiffness that is relevant to hepatic cells physiologically and pathologically. Methods Immunofluorescence and Western blotting were adopted to observe the morphological adjustment, motion characteristics, cytoskeleton arrangement of hepatocytes on polyacrylamide substrates with different stiffness, as well as the changes in expression of integrin and phenotypic markers E-cadherin, albumin and alpha-smooth muscle actin (α-SMA). Image analysis software was also used for quantitative study on the obtained data. Results On the 3.6 kPa substrates, the scattered single cells were actively deformed and relocated, but the bulk cell population had little change in polarization and microfilament organization. Muscle actin was assembled as cortical ring in cell periphery. There was more abundant expression of E-cadherin and albumin, but less expression of integrin and α-SMA in TGF-β1 treated group as compared to the control group. On the 30 kPa substrates, the motion and deformation of cells were not so active, and expression of both E-cadherin and albumin in TGF-β1 treated group was decreased, while that of α-SMA was increased as compared to the control group. For 30 kPa and 3.6 kPa control groups and 30 kPa and 3.6 kPa TGF-β1 treated groups, expression of both E-cadherin and albumin was reduced (P<0.05), but that of alpha-SMA was increased (P<0.05), while no significant differences were found in both 10 kPa control group and TGF-β1 treated group, as well as in 30 kPa and 3.6 kPa control groups and TGF-β1 treated groups. Conclusions The increase of substrate stiffness can induce transformation of hepatocyte phenotype and promote the influence of TGF-beta 1 on behavior of hepatocyte metabolism.