A liquid chromatography/tandem mass spectrometry method for determination of aristolochic acid-I in rat plasma.

A sensitive, rapid and specific liquid chromatography-electrospray ionization-tandem mass spectrometry method was developed and validated for the determination of aristolochic acid-I (AA-I) in rat plasma. Finasteride was used as the internal standard (IS). The analyte was separated on a Zorbax Eclipse XDB-C(18) column by isocratic elution with methanol-10 mM ammonium acetate (75:25, v/v, pH = 7.3) at a flow rate of 0.25 mL/min, and analyzed by mass spectrometry in positive multiple reaction monitoring mode. The precursor-to-product ion transitions of m/z 359.0 --> 298.2 and m/z 373.1 --> 305.2 were used to detect AA-I and IS, respectively. Good linearity was achieved over a range of 0.4-600 ng/mL. Intra- and inter-day precisions measured as relative standard deviation were less than 13.5%, and accuracy ranged from 94.2 to 97.5%. The developed method was successfully applied in the pharmacokinetic study of AA-I in rats.

[Determination of ginsenoside Rd and its metabolites in rat urine by LC-MS].

AIM: To study the metabolic pathways of ginsenoside Rd in rats. METHODS: Urine samples were collected before and after 24 h of single oral administration of 150 mg and intravenous administration of 60 mg of ginsenoside Rd to six rats, separately. The samples were purified by SPE column and then were analyzed by liquid chromatography-ESI-mass spectrometry for putative metabolites. RESULTS: Parent drug and its seven metabolites were identified in rat urine based on comparing total ion chromatograms of the blank with the metalolic urine as well as mass spectra. Its main metabolic pathways and possible structures are elucidated. CONCLUSION: Oxidation, combination and deglucosylation were found to be the major metabolic pathway of ginsenoside Rd in rats.

Effect of Sanqi Oral Liquid on the expressions of CD4⁺, CD8⁺ and CD68⁺ cells in 5/6 nephrectomized rats with chronic renal failure.

OBJECTIVE: To explore the mechanisms of Chinese herbal medicine Sanqi Oral Liquid, composed of Astragalus membranaceus and Panpax notoginseng, in alleviating renal injury by observing its effect on the expressions of CD4(+), CD8(+) and CD68(+) cells in 5/6 nephrectomized rats with chronic renal failure. METHODS: A total of 102 SD rats were randomly divided into six groups: three treatment groups were administrated with high, medium and low dosage of Sanqi Oral Liquid respectively by gavage; a normal group, a 5/6 nephrectomized model group, and a group treated with coated aldehyde oxygenstarch were used as controls. Following oral administration of Sanqi Oral Liquid for 12 weeks, the general condition and renal pathological changes were observed, and the renal function, platelet count (PLT) and the expressions of CD4(+), CD8(+) and CD68(+) cells were determined for each group. RESULTS: There were proliferation of mesangial matrix, renaltubularnecrosis and obvious tubulointerstitial fibrosis in the model group, and they were much milder in the treatment groups. Compared with the model group, the amounts of blood urea nitrogen (BUN), serum creatinine (Scr) and PLT in the treatment groups decreased (P<0.05 for all); and in the group administrated of medium dosage of Sanqi Oral Liquid, the expression of CD4(+) cells was up-regulated and those of CD8(+) and CD68(+) cells were down-regulated (P<0.05 for all), leading to an increased ratio of CD4(+)/CD8(+)(P<0.01). CONCLUSION: Sanqi Oral Liquid has a significant effect on regulating lymphocyte subsets, reducing the infiltration of macrophages in renal tissues and alleviating tubulointerstitial fibrosis, and this may be one of mechanisms of Sanqi Oral Liquid in delaying the progression of chronic kidney diseases.

A randomized double blind, placebo controlled trial of topical Tripterygium wilfordii in rheumatoid arthritis: reanalysis using logistic regression analysis.

OBJECTIVE: To assess the efficacy of topical Tripterygium wilfordii (TW), a Chinese herbal therapy, in rheumatoid arthritis (RA). METHODS: A 6 week randomized double blind placebo controlled study of 61 patients with RA meeting American College of Rheumatology (ACR) criteria was conducted in China. The primary outcome was a modified ACR-20 response rate, analyzed by logistic regression analysis. RESULTS: The modified ACR-20 response rate differed significantly (topical TW 58% vs placebo 20%; p = 0.002). There was an 8.1-fold (95% CI 1.9-35.4) increase in the modified ACR-20 response for the TW compared to the placebo group, adjusted for age and erythrocyte sedimentation rate. CONCLUSION: Topical TW appears efficacious for the treatment of RA, but larger studies are needed.