Determination of paeoniflorin, calycosin-7-O-β-d-glucoside, ononin, calycosin and formononetin in rat plasma after oral administration of Buyang Huanwu decoction for their pharmacokinetic study by liquid chromatography-mass spectrometry

Buyang Huanwu Decoction ameliorates atherosclerosis by regulating TGF-β/Smad2 pathway to promote the differentiation of regulatory T cells

ETHNOPHARMACOLOGICAL RELEVANCE

As a classic prescription of Traditional Chinese Medicine in Correction on the Errors of Medical Works, Buyang Huanwu Decoction (BYHWD) has a good curative effect on prevention of atherosclerosis (AS).

AIM OF THE STUDY

This study aims to elucidate the anti-atherosclerosis mechanism of BYHWD, which may promote the differentiation of regulatory T cells by regulating the TGF-β/Smad2 pathway.

MATERIALS AND METHODS

ApoE-/- mice were fed a high-fat diet for 12 weeks, then drugs group were given BYHWD with intragastric administration once a day for 4 weeks. The effect of BYHWD on lipid content in peripheral blood and plaque was evaluated by blood lipid test and oil red O staining. The number of Tregs in peripheral blood was tested by flow cytometry, and that in the spleen was evaluated by immunohistochemistry methods. Gene and protein expression relating with Tregs differentiation pathway in mice were checked by RT-PCR and Western blot experiments. CD4+T cells were isolated and interfered by BYHWD drug-loaded serum. The proportion of Tregs was evaluated by flow cytometry. The chemical compositions of BYHWD and rat drug-loaded serum were analyzed by ultra-high performance liquid chromatograph and liquid chromatography-tandem mass spectrometry.

RESULTS

BYHWD significantly reduced plaque area and cholesterol accumulation, increased the number of Tregs in spleen and peripheral blood of ApoE-/- AS mice, raised the proportion of Tregs in CD4+T cells, and regulated the levels of inflammatory factors. It also increased the TGF-β and Smad2 mRNA and protein levels relating with Tregs differentiation pathway in vivo. The mRNA levels of Foxp3/TGF-β/Smad2 were enhanced via BYHWD in vitro.

CONCLUSIONS

BYHWD regulates TGF-β/Smad2 signaling pathway to promotes the peripheral differentiation of Tregs, increases the number of Tregs, restores the immune balance between CD4+T cells, regulates lipid metabolism, inhibits inflammatory reaction and possesses the potential of enhancing plaque stability.

Comparative pharmacokinetic study on three formulations of Astragali Radix by an LC-MS/MS method for determination of formononetin in human plasma

Astragali Radix (AR) is a widely used traditional Chinese medicine for healing the cardiovascular, liver and immune systems. Recently, superfine pulverizing technology has been applied to developing novel formulations to improve bioavailability of the active constituents in herbs, such as ultrafine granular powder of AR. In this study, a universal and sensitive quantitative method based on LC-MS/MS was employed for determining formononetin, the main flavonoid in AR, in human plasma for comparative pharmacokinetics of three oral formulations of AR. Formononetin and IS (quercetin) were extracted by ethyl acetate from human plasma and were separated on a C₁₈ column with a mobile phase consisting of acetonitrile and 0.1% formic acid. Positive-ion electrospray-ionization mode was applied in mass spectrometric detection. The quantitative method was validated with regards to selectivity, linearity, accuracy and precision, matrix effect, extraction recovery and stability, and was applied to comparing the pharmacokinetics of ultrafine granular powder (UGP), ultrafine powder (UP) and traditional decoction pieces (TDP) of AR after oral administration. The peak concentration and areas under the concentration-time curve of formononetin in UGP and UP were significantly higher than those of TDP. UGP and UP could significantly improve the bioavailability of AR in human compared with TDP after oral administration.

Simultaneous determination of major components of Huangqi-Honghua extract in rat plasma using LC-MS/MS and application to a pharmacokinetic study

A sensitive and reliable LC-MS/MS method was developed and validated for simultaneous quantification of the major components of Huangqi-Honghua extact in rat plasma, including hydroxysafflor yellow A (HSYA), astragaloside IV (ASIV), calycosin-7-O-β-d-glucoside (CAG), calycosin, calycosin-3'-O-glucuronide (C-3'-G) and calycosin-3'-O-sulfate (C-3'-S). After extraction by protein precipitation with acetonitrile and methanol from plasma, the analytes were separated on a Hypersil BDS C₁₈ column by gradient elution with acetonitrile and 5 mM ammonium acetate. The detection was carried out on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization source switched between negative and positive modes. HSYA was monitored in negative ionization mode from 0 to 4.9 min, and ASIV, CAG, calycosin, C-3'-G and C-3'-S were determined in positive ionization mode from 4.9 to 10 min. The lower limits of quantification of the analytes were 6.25 ng/mL for HSYA, 0.781 ng/mL for CAG and 1.56 ng/mL for ASIV and calycosin. The intra- and inter-assay precision (RSD) values were within 13.43%, and accuracy (RE) ranged from -8.75 to 9.92%. The validated method was then applied to the pharmacokinetic study of HSYA, ASIV, CAG, calycosin, C-3'-G and C-3'-S in rat after an oral administration of Huangqi-Honghua extract.

Advancement in the chemical analysis of Paeoniae Radix (Shaoyao)

Paeoniae Radix Alba (baishao or white peony root) and Paeoniae Radix Rubra (chishao or red peony root) are two highly valuable traditional Chinese medicines (TCMs) usually indicated for painful conditions, menstrual disorders and viral infections. These two TCMs are collectively referred to as shaoyao (Paeoniae Radix) due to their close origins and similar chemical compositions. Modern research indicates that monoterpene glycosides, polyphenols and paeonols are the three main types of compounds related to the pharmacological activities of Paeoniae Radix. This review summarizes recent advances in the chemical analysis of Paeoniae Radix and the related traditional Chinese medicine formulas/preparations, including methods used for sample pretreatment, qualitative analysis, quantitative analysis and biological sample analysis. More than 120 papers are discussed in this review, focusing on the chemical analysis of Paeoniae Radix, and various analytical techniques (such as HPLC, LC-MS, IR, near IR and quantitative NMR), as well as their advantages/disadvantages, are described. It is our hope that this paper can provide necessary information for improving the quality evaluation methods currently available for Paeoniae Radix and offer a scientific basis for the future in-depth study of the pharmacokinetics and pharmacodynamics of Paeoniae Radix.

Pharmacokinetics and Bioavailability of the Isoflavones Formononetin and Ononin and Their in Vitro Absorption in Ussing Chamber and Caco-2 Cell Models

Formononetin and its glycoside ononin are bioactive isoflavones widely present in legumes. The present study investigated the pharmacokinetics, bioavailability, and in vitro absorption of formononetin and ononin. After an oral administration to rats, formononetin showed a higher systemic exposure over ononin. The oral bioavailability of formononetin and ononin were 21.8% and 7.3%, respectively. Ononin was more bioavailable than perceived, and its bioavailability reached 21.7% when its metabolite formononetin was taken into account. Both formononetin and ononin exhibited better absorption in large intestine segments than that in small intestine segments. Formononetin displayed a better permeability in all intestinal segments over ononin. Transport of formononetin across Caco-2 cell monolayer was mainly through passive diffusion, while ononin was actively pumped out by MRP2 but not P-gp. The results provide evidence for better understanding of the pharmacological actions of formononetin and ononin, which advocates more in vivo evaluations or human trials.

Buyang Huanwu Decoction attenuates H2O2-induced apoptosis by inhibiting reactive oxygen species-mediated mitochondrial dysfunction pathway in human umbilical vein endothelial cells

Background

Apoptosis of endothelial cells caused by reactive oxygen species plays an important role in ischemia/reperfusion injury after cerebral infarction. Buyang Huanwu Decoction (BYHWD) has been used to treat stroke and stroke-induced disability, however, the mechanism for this treatment remains unknown. In this study, we investigated whether BYHWD can protect human umbilical vein endothelial cells (HUVECs) from H₂O₂-induced apoptosis and explored the underlying mechanisms.

Methods

To investigate the effect of BYHWD on the apoptosis of HUVECs, we established a H₂O₂-induced oxidative stress model and detected apoptosis by Hoechst 33342 and propidium iodide staining. JC-1 and DCFH-DA assays,western blotting and electron microscopy were used to examine the mechanism of BYHWD on apoptosis.

Results

Pretreatment with BYHWD significantly inhibited H₂O₂-induced apoptosis and protein caspase-3 expression in a concentration-dependent manner. In addition, BYHWD reduced reactive oxygen species production and promoted endogenous antioxidant defenses. Furthermore, loss of mitochondrial membrane potential and structural disruption of mitochondria were both rescued by BYHWD.

Conclusions

BYHWD protects HUVECs from H₂O₂-induced apoptosis by inhibiting oxidative stress damage and mitochondrial dysfunction. These findings indicate that BYHWD is a promising treatment for cerebral ischemia diseases.

Pharmacokinetic comparison of seven major bio-active components in normal and blood deficiency rats after oral administration of Danggui Buxue decoction by UPLC-TQ/MS

ETHNOPHARMACOLOGICAL RELEVANCE

Blood deficiency is commonly encountered among women, and is the root of many gynecological disorders. Danggui Buxue Decoction (DBD), a classical traditional Chinese formula which is composed of Astragali Radix (AR) and Angelicae Sinensis Radix (ASR) at the ratio of 5:1 (w/w), is widely used in TCM clinics for treatment of blood deficiency syndrome. This study is to compare the in vivo pharmacokinetic properties of seven major bio-active components in normal and blood deficiency rats after oral administration of DBD.

MATERIALS AND METHODS

Blood deficiency rats were induced by bleeding from orbit at the dosages of 5.0mL/kg each day for 12 days. Normal and blood deficiency rats were administrated of DBD on the 12th day at the dosage of 20g/kg, and blood was collected at different time points after then. Concentrations of ferulic acid, caffeic acid, butylphthalide, ligustilide, calycosin-7-O-β-glucoside, ononin, and astragaloside IV in plasma were quantified by UPLC-TQ/MS, and the main pharmacokinetic parameters were calculated by DAS 2.0.

RESULTS

It was found that Cmax, Tmax and MRT0~T of astragaloside IV, Cmax, T1/2Z, AUC0~T and MRT0~T of calycosin-7-O-β-glucoside, T1/2Z and AUC0~T of ferulic acid, T1/2Z, AUC0~T and MRT0~T of ononin, and MRT0~T of ligustilide, butylphthalide, and caffeic acid in blood deficiency rats was significantly different (P<0.05) from normal rats.

CONCLUSIONS

This study was the first report about pharmacokinetic investigation in blood deficiency animals which was conducted by bleeding. And the results demonstrated that the seven DBD constituents in normal and blood deficiency rats had obvious differences in some pharmacokinetic characteristics, suggesting that the rate and extent of drug metabolism were altered in blood deficiency animals.

HPLC-MS/MS analysis of a traditional Chinese medical formulation of Bu-Yang-Huan-Wu-Tang and its pharmacokinetics after oral administration to rats

Bu-yang-huan-wu-tang (BYHWT) is one of the most popular formulated traditional Chinese medicine prescriptions, and is widely for prevention of ischemic cardio-cerebral vascular diseases and stroke-induced disability. A specific high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) has been developed and validated for simultaneous quantification of the nine main bioactive components, i.e., astragaloside I, astragaloside II, astragaloside IV, formononetin, ononin, calycosin, calycosin-7-O-β-d-glucoside, ligustilide and paeoniflorin in rat plasma after oral administration of BYHWT extract. This method was applied to investigate the pharmacokinetics in conscious and freely moving rats. No significant matrix effects were observed. The overall analytical procedure was rapid and reproducible, which makes it suitable for quantitative analysis of a large number of samples. Among them, three astragalosides and four isoflavones in A. membranaceus, ligustilide in Radix Angelicae Sinensis and Rhizoma Ligustici Chuanxiong and paeoniflorin in Radix Paeoniae Rubra were identified. This developed method was then successfully applied to pharmacokinetic studies of the nine bioactive constituents after oral administration of BYHWT extracts in rats. The pharmacokinetic data demonstrated that astragaloside I, astragaloside II, astragaloside IV and ligustilide presented the phenomenon of double peaks. The other herbal ingredients of formononetin, ononin, calycosin, calycosin-7-O-β-d-glucoside and paeoniflorin appeared together in a single and plateau absorption phase. These phenomenona suggest that these components may have multiple absorption sites, regulation of enterohepatic circulation or the gastric emptying rate, or there is ingredient-ingredient interaction. These pharmacokinetic results provide a constructive contribution to better understand the absorption mechanism of BYHWT and to support additional clinical evaluation.

Identification of metabolites of Buyang Huanwu decoction in rat urine using liquid chromatography-quadrupole time-of-flight mass spectrometry

In the present study, rapid resolution liquid chromatography was coupled with quadrupole time-of-flight tandem mass spectrometry (RRLC-Q-TOF-MS) to identify the absorbed components and metabolites in rat urine after oral administration of Buyang Huanwu decoction (BYHWD). After oral administration of BYHWD, urine samples were collected and pretreated by solid phase extraction. The mass measurements were accurate within 5 ppm of error for all the protonated molecules, and subsequent fragment ions offered higher quality structural information for interpretation of the fragmentation pathways of various compounds. A total of 50 compounds were detected in rat urine samples within 20 min, including 12 parent compounds and 38 metabolites. Except for three prototype components (Hydroxysafflor yellow A, Paeoniflorin, and Amygdalin), the metabolites identified mainly came from Radix Astragali, Radix Angelicae Sinensis, and Rhizoma Chuanxiong. The results indicated that glucuronidation and sulfation were the major metabolic pathways of isoflavonoids, while glutathione conjugation, glucuronidation and sulfation were the main metabolic pathways of phthalides. No saponin-related metabolites were detected. The present study provided important structural information on the metabolism of BYHWD. Furthermore, the results of this work have demonstrated the feasibility of the RRLC/ESI-Q-TOF-MS approach for rapid and reliable characterization of metabolites from herbal medicines.