Impact of extended ginsenoside Rb1 on early chronic kidney disease: a randomized, placebo-controlled study.

Ginsenoside Rb1 (GS-Rb1) is a well-known antioxidant derived from traditionally used herbal medicine ginseng. It has been suggested that reactive oxygen species (ROS) is involved in chronic kidney disease (CKD) in which GS-Rb1 may play a protective role. The aim of this study was to evaluate prospectively the effects of GS-Rb1 in patients with early chronic kidney disease. 197 patients who have been diagnosed with early CKD (stage 2 or 3) were recruited and randomly assigned to receive GS-Rb1 (500 mg daily oral administration, n = 103) or placebo (n = 94) for consecutive 6 months. Analytical procedures performed at baseline, the end of the treatments, and 6 months after the treatments included renal function evaluation (creatinine and urea clearance), oxidative stress measurement, inflammation assessment, and lipid profile. Of 177 patients completing the study, the GS-Rb1 group (n = 91) showed a positive response in significantly alleviating renal function impairments compared to the placebo group (n = 86). In addition, GS-Rb1 treatment was effective in reducing the extent of oxidative stress and inflammation in CKD patients, whereas continued deterioration was observed in the placebo group. Thus, extended treatment of patients using GS-Rb1 may present an antioxidant-based approach to slow the progression of CKD at the early stages.

Application of an in vitro DDASS to evaluate oral absorption of two chemicals simultaneously: establishment of a level A in vitro-in vivo correlation.

The aim of this study was to evaluate the oral absorption of two chemicals simultaneously using a drug dissolution/absorption simulating system (DDASS), and to establish a correlation between DDASS and in vivo absorption to clarify the prediction of this in vitro model. Ferulic acid (FA) and tetrahydropalmatine (THP), the components of Angelicae Sinensis Radix and Corydalis Yanhusuo Rhizoma, respectively, were chosen as model compounds. Three groups including FA, THP, and FA and THP together (FA + THP) were studied in DDASS. The corresponding in vivo pharmacokinetics study was performed in rats. Then the correlation was analysed between DDASS permeation in vitro and rat absorption data in vivo. A strong level A correlation (r > 0.84) was obtained after a correlation coefficient test (p < 0.05 or 0.01). Moreover, when FA and THP were used together in DDASS, the cumulative permeation of FA increased by 38.5%, while THP permeation decreased by 25.8%. In rats, the area under the concentration-time curve from time to infinity for FA increased 2.6-fold, while THP decreased 19.6%. The changes in rat intestinal permeation modeled by the DDASS were consistent with the absorption changes in rats. We conclude that DDASS is a valid in vitro model to evaluate oral absorption of two drug components simultaneously and reflect the in vivo characteristics of drug absorption accurately.

Pharmacokinetic study of borneol and menthol in rats after oral administration of qingyan drop pills.

Both borneol and menthol are bioactive substances derived from Chinese herbal medicines. In order to understand the pharmacokinetics of borneol and menthol in Qingyan drop pills, a rapid, sensitive, and simple gas chromatographic (GC) method with flame ionization detection (FID) was developed for the simultaneous determination of borneol and menthol in rat plasma. Sample preparations were carried out by liquid-liquid extraction (LLE) with an internal standard solution of naphthalene. The analytes and internal standard (IS, naphthalene) were separated well on an HP-1 capillary column. The pharmacokinetic parameters were estimated by a compartmental method using the Phoenix WinNonlin software program (Version 6.0). The standard curves were linear over a wide concentration range of 2.5-50.0 ng/µL ( R = 0.9963), 8.7-62.2 ng/µL ( R = 0.9994) for both borneol and menthol in plasma, respectively. The limits of quantification (LOQ) of borneol and menthol in plasma were 2.4 ng/µL and 5.0 ng/µL, respectively. The intra-day precisions for borneol and menthol were < or = 10.0 % R. S. D. at the LOQ and < or = 6.0 % at higher concentrations. The average value of CMAX was 18.97 ± 2.71 ng/µL with a TMAX at 20.00 ± 0.00 min for borneol after oral administration of the drop pills; for menthol, the average value of CMAX was 79.02 ± 11.40 ng/µL with a TMAX at 25.00 ± 4.40 min. This validated assay method was successfully applied to a pharmacokinetic study of borneol and menthol after oral administration of Qingyan drop pills in rat. The results showed that the kinetics of borneol and menthol can be described by an open one-compartment model. The pharmacokinetic parameters provide some information for clinical administration of Qingyan drop pills.