ABSTRACT
Morus alba L. (mulberry) is a well-known deciduous tree, belonging to the genus of Morus of Moraceae famlily. Its leaves, twigs, roots (bark) and fruits are widely used in the traditional Chinese medicine. The active constituents of mulberry contained flavonoids, alkaloids, steroids, coumarins, with the significant hypoglycemic, hypolipidemic, antihypertension, anti-oxidation, anti-inflammatory, anti-bacterial, anti-tumor and immunomodulatory activities. This review summarized the research progress of the major pharmacological activity, pharmacokinetics and drug-drug interaction based on CYPs and transporters of mulberry and its active constituents.
ABSTRACT
It is valuable to establish a chemical-pharmacokinetic (PK)-pharmacodynamics (PD) fingerprint of traditional Chinese medicine (TCM) for comprehensively understanding the TCM integrated conception and revealing the material foundation. The chemical, metabolic in vitro, and PK/PD in vivo fingerprints of Schisandra chinensis (SC) alcoholic extract were established and comparatively analyzed using HPLC-UV-MS method, rat liver microsomes in vitro and CCl4 intoxicated rats in vivo. Four known effective lignans, schisandrin, schisantherin A, deoxyschizandrin and gamma-schisandrin, were detected as the standard references in SC alcoholic extract with high concentration. SC alcoholic extract and four lignans when incubated with rat liver microsomes produced several metabolites in NAPDH-dependent manner. Chemical fingerprint of some components with bioactivities were also identified in PK and PD fingerprints in normal and ALI rats that explained the material foundation of SC alcoholic extract for multiple pharmacological effects. Schisandrin, schisantherin A, deoxyschizandrin and gamma-schisandrin could be considered as the "PK marker" of SC alcoholic extract or its relevant preparations, while two metabolites of the four lignans, 7, 8-dihydroxy-schizandrin and another one (M(W) 432), could be recognized as drug-metabolism (DM) Marker. This work provides experimental data for the further studies of metabolism or material foundation of SC components.
ABSTRACT
A simple, rapid and sensitive method was developed for the quantification of tenofovir in plasma of Beagle dogs using HPLC-MS/MS analysis. The analytes tenofovir and internal standard (IS) adefovir were separated on a Zorbax SB-C18 column (3.5 microm, 100 mm x 2.1 mm, Agilent, USA) with mobile phase of methanol/water containing 0.3% formic acid using a gradient elution mode at a flow rate of 0.2 mL x min(-1). The plasma sample preparation was a simple deproteinization by the addition of 20% trichloroacetic acid followed by centrifugation. The detection was performed in positive selected reaction monitoring (SRM) mode with an electrospray ionization (ESI) source. The reactions monitored were m/z 288.1-176.2 for tenofovir and m/z 274.1-162.2 for adefovir (IS). Linear detection responses were obtained for tenofovir ranging from 10 to 5 000 ng x mL(-1). The intra- and inter-day precisions (RSD%) was no more than 6.3% with high recovery and good stability for the quantification, indicating the present method was specific, fast, accurate and reliable. The method was successfully applied to the pharmacokinetic study of two tenofovir agents. Tenofovir dipivoxil fumarate (BP0018, test agent) and tenofovir disoproxil fumarate (reference agent) were orally administrated to 8 Beagle dogs according to the 2 x 2 crossover design. Comparing with the reference agent, the longer MRT and t1/2 were obtained in the group of BP0018, while no significant difference was observed in AUC(0-t), AUC(0-infinity), C(max) and t(max) between them, suggesting that tenofovir dipivoxil fumarate was bioequivalent to the tenofovir disoproxil fumarate in Beagle dogs.
ABSTRACT
Effects of constituents from Schisandra chinensis (Wuweizi) on six liver microsomal CYP450 isozymes (CYP1A2, CYP2C6, CYP2C11, CYP2D2, CYP2E1 and CYP3A1/2) were studied in rats in vivo and in vitro. The in vitro incubation was conducted using liver microsomes of rats after multiple dosing of alcoholic/water extract from Schisandra chinensis. A HPLC-MS method was applied to determine the metabolites formation of six CYP450s probe substrates (phenacetin-CYP1A2, dextromethorphan-CYP2D2, diclofenac sodium-CYP2C6, mephenytoin-CYP2C11, chlorzoxazone-CYP2E1 and midazolam-CYP3A1/2) in rat liver microsomal incubations. The activity of CYP450 isozymes were represented by the formation of metabolites. Alcoholic extract of Schisandra chinensis (28-120 microg x mL(-1)) showed significant inhibitory effect on six CYP450 isozymes to a certain extent in vitro. Multiple dosing of Schisandra chinensis alcoholic extract (1.5 g x kg(-1), qd x 7d) had significant induction on CYP2E1 and CYP3A1/2, inhibition on CYP2D2 and CYP2C11, and no effect on CYP2C6 and CYP1A2. Water extract of Schisandra chinensis (100-500 microg x mL(-1)) also exhibited inhibition on the activity of CYP450 isozymes in vitro, whereas multiple administrations (1.5 g x kg(-1), qd x 7d) had significant induction of CYP2E1 and inhibition on CYP2D2, no effect on CYP2C6, CYP3A1/2, CYP1A2 or CYP2C11. The results suggested that the constituents from Schisandra chinensis exhibited the inhibition and induction on six rat liver microsomal CYP450 isozymes to a certain extent in vivo and in vitro. The possibility of interaction between Schisandra chinensis and coadministrative drugs will be considered base on the levels and subtype of CYP450 involved in the drug metabolism.
ABSTRACT
Clinical nursing needs not only skill,but also high moral level,which is important to guarantte the quality of medical care.According to the ethical difficulty and moral problems in clinical nursing,the article makes primary research and discussion on nurse's psychological quality,skill and ability,sense of responsibility and the relationships.It also expounds the importance of nursing in clinic and the relationship between doctor and patient from the two aspects of improving nurse's technique skill level and ethical moral level to promote the development of clinical work and nursing.