[Pharmacokinetic comparison between Tanreqing Capsules Substitute and Tanreqing Capsules in rats by LC-MS/MS].

Due to the limited resource of bear bile powder, the major raw material of Tanreqing Capsules(TRQ), cultured bear bile powder is used as a replacement to develop the Tanreqing Capsules Substitute(TRQS). An LC-MS/MS method was established in this study for simultaneous quantitation of 8 compounds from TRQS in rat plasma: tauroursodeoxycholic acid(TUDCA), taurocheno-deoxycholic acid(TCDCA), ursodeoxycholic acid(UDCA), chenodeoxycholic acid(CDCA), ferulic acid, wogonoside, baicalin, and forsythoside A. Thereby, the pharmacokinetic behaviors of TRQ and TRQS were evaluated. Concentration of endogenous compounds TUDCA, TCDCA, UDCA, and CDCA was determined with the stable isotope surrogate analytes: D4-TUDCA, D4-TCDCA, D4-UDCA, and D4-CDCA. Plasma samples were extracted by acetonitrile-induced protein precipitation. The LC conditions are as follows: Waters BEH C_(18) column(2.1 mm×100 mm, 1.7 µm), mobile phase of 10 mmol·L~(-1) ammonium formate aqueous solution(containing 0.01% formic acid) and acetonitrile-methanol mixture(1∶5). MS conditions are as below: multiple reaction monitoring(MRM), ESI~(+/-). Concentration of UDCA, CDCA, TUDCA, and TCDCA was corrected with a response factor, which is the ratio between the responses recorded for the surrogate and the authentic analyte at the equal concentration. Each of the plasma components showed good linearity(r > 0.995 1). Accuracy and precision met the criteria(inter-day RSD<7.0%, RE 89.98%-112.0%; intra-day RSD<12%, RE 90.41%-111.2%). The recovery was 64.83%-119.9% and matrix effect was 87.15%-113.8%. The validated method was applied for pharmacokinetic study of TRQS and TRQ(po, 0.94 g·kg~(-1)). There was no significant difference in C_(max) and AUC_(0-24 h) of baicalin, UDCA, TUDCA, and TCDCA between the two groups, indicating similar pharmacokinetic behaviors between TRQS and TRQ in rats.

Quantitative Proteomics Reveals the Protective Effects of Huangqi Decoction Against Acute Cholestatic Liver Injury by Inhibiting the NF-κB/IL-6/STAT3 Signaling Pathway.

Intrahepatic cholestasis (IC) is a common syndrome that affects the liver, with treatment options being limited. Huangqi decoction (HQD), a classic herbal medicine, has shown protective effects against IC. In this study, isobaric tags for relative and absolute quantification-based quantitative proteomics was performed to investigate the potential mechanism of action of HQD on α-naphthylisothiocyanate (ANIT)-induced IC, resulting in 2796 quantified proteins across all samples, including 270 differentially expressed proteins under HQD treatment. Fuzzy c-means clustering analysis of these 270 proteins assigned the proinflammatory proteins, such as LCN2, SAA1, FGG, FGA, and FGB, to Cluster 1 (upregulated by ANIT, and downregulated by HQD). Functional bioinformatics and protein-protein interaction network analyses indicated that these proinflammatory proteins were involved in the STAT3 signaling pathway. Further real-time PCR and Western blot experiments confirmed that the expression of these proteins was consistent with the proteomic results. Moreover, HQD treatment decreased the phosphorylation of STAT3, induced by ANIT. Western blot experiments revealed that HQD treatment decreased phosphorylation of NF-κB and downregulated the expression of the inflammatory gene IL-6 and therefore inhibited the IL-6/STAT3 signaling pathway. In summary, the present study suggested that HQD may ameliorate acute cholestatic liver injury via inhibition of the NF-κB/IL-6/STAT3 signaling pathway.

Subcellular drug distribution: mechanisms and roles in drug efficacy, toxicity, resistance, and targeted delivery.

After administration, drug molecules usually enter target cells to access their intracellular targets. In eukaryotic cells, these targets are often located in organelles, including the nucleus, endoplasmic reticulum, mitochondria, lysosomes, Golgi apparatus, and peroxisomes. Each organelle type possesses unique biological features. For example, mitochondria possess a negative transmembrane potential, while lysosomes have an intraluminal delta pH. Other properties are common to several organelle types, such as the presence of ATP-binding cassette (ABC) or solute carrier-type (SLC) transporters that sequester or pump out xenobiotic drugs. Studies on subcellular drug distribution are critical to understand the efficacy and toxicity of drugs along with the body's resistance to them and to potentially offer hints for targeted subcellular drug delivery. This review summarizes the results of studies from 1990 to 2017 that examined the subcellular distribution of small molecular drugs. We hope this review will aid in the understanding of drug distribution within cells.

Simultaneous quantification of multiple components in rat plasma by UPLC-MS/MS and pharmacokinetic study after oral administration of Huangqi decoction.

A rapid, sensitive and accurate UPLC-MS/MS method was developed for the simultaneous quantification of components of Huangqi decoction (HQD), such as calycosin-7-O-ß-d-glucoside, calycosin-glucuronide, liquiritin, formononetin-glucuronide, isoliquiritin, liquiritigenin, ononin, calycosin, isoliquiritigenin, formononetin, glycyrrhizic acid, astragaloside IV, cycloastragenol, and glycyrrhetinic acid, in rat plasma. After plasma samples were extracted by protein precipitation, chromatographic separation was performed with a C18 column, using a gradient of methanol and 0.05% acetic acid containing 4mm ammonium acetate as the mobile phase. Multiple reaction monitoring scanning was performed to quantify the analytes, and the electrospray ion source polarity was switched between positive and negative modes in a single run of 10 min. Method validation showed that specificity, linearity, accuracy, precision, extraction recovery, matrix effect and stability for 14 components met the requirements for their quantitation in biological samples. The established method was successfully applied to the pharmacokinetic study of multiple components in rats after intragastric administration of HQD. The results clarified the pharmacokinetic characteristics of multiple components found in HQD. This research provides useful information for understanding the relation between the chemical components of HQD and their therapeutic effects.

A Compositive Strategy to Study the Pharmacokinetics of TCMs: Taking Coptidis Rhizoma, and Coptidis Rhizoma-Glycyrrhizae Radix et Rhizoma as Examples.

Pharmacokinetic studies are crucial for elucidating the effective constituents and formula compatibility of traditional Chinese medicines (TCMs). However, studies have usually been limited to single dosages and detection of systemic blood concentrations. To obtain comprehensive pharmacokinetic information, here we propose a multi-dosage and multi-sampling (blood from portal vein or systemic circulation, and liver) strategy to comparatively study the pharmacokinetics of multi-form TCMs, i.e., pure constituents, TCMs, or TCM formula extracts. Based on this strategy, we studied the pharmacokinetics of pure berberine, berberine in CoptidisRhizoma (CRE), and berberine in CoptidisRhizoma-GlycyrrhizaeRadix etRhizoma extracts (CR-GRE). After simple calculation and comparison of the obtained area under the curve (AUC) values, the results revealed the drastically different pharmacokinetic properties of pure berberine compared to CRE and CR-GRE. The results contribute to explaining the pharmacological loss of berberine activity after purification and the compatibility of the CR-GR drug pair. The results also innovatively showed that it was intestinal absorption that differentiated the pharmacokinetics of CRE and pure berberine, and CRE and CR-GRE. In conclusion, we propose a composite strategy to comparatively study the pharmacokinetics of TCMs, which could provide sufficient information to obtain a comprehensive view, before follow-up mechanism-of-action studies.

Pharmacokinetic herb-drug interactions with traditional Chinese medicine: progress, causes of conflicting results and suggestions for future research.

Traditional Chinese medicine (TCM) has a long history of medical use in China and is still used worldwide. Unexpected herb-drug interactions (HDIs) may lead to adverse drug reactions or loss of therapeutic efficacy of the victim drug. Here, based on searches of Medline, EBSCO, Science Direct and Web of Science using various keywords, we summarize the TCM-derived pharmacokinetic HDIs that were reported from 1990 to 2015 and discuss the underlying mechanisms. In general, many pre-clinical and clinical pharmacokinetic HDIs have been reported. Our searches show that TCMs cause pharmacokinetic interactions with therapeutic drugs mainly by inhibiting or inducing drug-metabolizing enzymes and transporters. However, most of the interactions result from a small number of prescription medications and the actual potential for harm is low. Moreover, such HDIs can be avoided by discontinuing the TCMs. Despite the extensive number of reports on TCM-derived HDIs, the findings are frequently conflicting and can be confusing. The causes of the conflicts vary, but we classified them into three basic categories as follows: (1) complicated nature and poor quality control of TCMs, (2) different responses of various test systems to TCM exposure and (3) diverse study designs. Accordingly, we propose rational study designs for future HDI research. We also propose that a specific authoritative guide be established that provides recommendations for HDI studies. This review provides insights into the progress and challenges in TCM-derived pharmacokinetic HDI research.

[Effect of Huangqi decoction on entecavir pharmacokinetics in rat plasma].

Entecavir (ETV), a guanosine nucleotide antiviral agent with activity against hepatitis B virus (HBV) and Huangqi decoction (HQD) that exerts significant therapeutic effects in liver cirrhosis are used as an effective drug combination in the treatment of liver cirrhosis with HBV. Therefore, this study was designed to assess the effect of HQD on ETV pharmacokinetics in rat plasma. Spraque-Dawley (SD) rats were randomized into single- and 7-day-dose experimental groups. The ETV and ETV-HQD groups were administered ETV and a simultaneous combination of ETV and HQD, respectively while the ETV-HQD-2h group received HQD 2 h after ETV treatment, all administered via intragastric (i.g.) gavage. A rapid, sensitive, and efficient ultra-high- performance liquid chromatography-linear trap quadrupole (UHPLC-LTQ)-Orbitrap method was developed and validated to determine ETV in rat plasma from blood samples collected at different time points following treatment. The linearity, accuracy, precision, recovery, matrix effects and stability of ETV were all satisfactory. The ETV-HQD group exhibited a decrease in the maximum plasma concentration (Cmax), and a delay in time to achieve Cmax (tmax) following single- and multi-dose administrations, and decreased area under the concentration- time curve (AUC0­t) following single dosing. ETV pharmacokinetics did not change significantly between the ETV and ETV-HQD-2h groups. In vitro everted intestinal sac models experiments indicated that HQD decreased the absorption of ETV. HQD prevented ETV from accessing the intestinal mucosa epithelial surface, thereby decreasing its absorption in rats.

Icariin, a phosphodiesterase-5 inhibitor, improves learning and memory in APP/PS1 transgenic mice by stimulation of NO/cGMP signalling.

Phosphodiesterase-5 (PDE5) inhibitors are predominantly used in the treatment of erectile dysfunction, and have been recently shown to have a potential therapeutic effect for the treatment of Alzheimer's disease (AD) through stimulation of nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signalling by elevating cGMP, which is a secondary messenger involved in processes of neuroplasticity. In the present study, the effects of a PDE5 inhibitor, icarrin (ICA), on learning and memory as well as the pathological features in APP/PS1 transgenic AD mice were investigated. Ten-month-old APP/PS1 transgenic mice overexpressing human amyloid precursor protein (APP695swe) and presenilin 1 (PS1-dE9) were given ICA (30 and 60 mg/kg) or sildenafil (SIL) (2 mg/kg), age-matched wild-type (WT) mice were given ICA (60 mg/kg), and APP/PS1 and WT control groups were given an isovolumic vehicle orally twice a day for four months. Results demonstrated that ICA treatments significantly improved learning and memory of APP/PS1 transgenic mice in Y-maze tasks. The amyloid precursor protein (APP), amyloid-beta (Aß1-40/42) and PDE5 mRNA and/or protein levels were increased in the hippocampus and cortex of APP/PS1 mice, and ICA treatments decreased these physiopathological changes. Furthermore, ICA-treated mice showed an increased expression of three nitric oxide synthase (NOS) isoforms at both mRNA and protein levels, together with increased NO and cGMP levels in the hippocampus and cortex of mice. These findings demonstrate that ICA improves learning and memory functions in APP/PS1 transgenic mice possibly through the stimulation of NO/cGMP signalling and co-ordinated induction of NOS isoforms.

[Progress in the study of multidrug and toxin extrusion proteins].

Mammal multidrug and toxin extrusion proteins (MATEs) play an important role in the transport of organic cations in the body. MATEs mediate the final excretion step for multiple organic cation drug used clinically and important endogenous substances. This article reviews the discovery, type, gene coding and polymorphism, body distribution, classification of substrates and inhibitors and their research method of MATEs. The article also discusses the major research significance of MATEs with examples.

[Progress in methodology of establishing physiologically based pharmacokinetic models].

Physiologically based pharmacokinetic model (PBPK), a mechanistic mathematic model, which can simulate the absorption, distribution, metabolism and excretion of drugs, is being more widely used in pharmaceutical research and development areas. This article reviews primarily the recent advances in the procedure of establishing a PBPK model, including specifying of the PBPK model structure, specification of the tissue model, writing of equations, set of model parameters, simulation and evaluation. Application significance, major challenges and future developments of PBPK model in pharmaceutical areas are also discussed.

Differences in pharmacokinetics and anti-inflammatory effects between decoction and maceration of Sanhuang Xiexin Tang in rats and mice.

The pharmacokinetics and anti-inflammatory effects of Sanhuang Xiexin Tang, composed of Rhei Radix et Rhizoma, Scutellariae Radix, and Coptidis Rhizoma, prepared by decoction and maceration, were investigated and compared. Rats were orally administered with the decoction and maceration of Sanhuang Xiexin Tang at 30 g/kg. The concentrations of 10 active constituents (berberine, palmatine, jatrorrhizine, coptisine, wogonin, baicalin, wogonoside, emodin, aloe-emodin, and rhein) in plasma were determined by UPLC-MS/MS. Mice were orally administered decoctions and macerations of Sanhuang Xiexin Tang continuously for 7 days at three doses and stimulated with lipopolysaccharide. The plasma concentrations of IL-10 and TNF-α were determined by ELISA. Different preparation methods resulted in significant differences in the pharmacokinetic characteristics of the SXT constituents, especially the protoberberine alkaloids. Maceration decreased the absorption of flavones while promoting the absorption of anthraquinones. Bioavailability of both flavones and anthraquinones increased after administration of macerated Sanhuang Xiexin Tang, especially those of baicalin and rhein, which increased by 3.27 and 7.10 times. Results of ELISA indicated that both the decoction and maceration of Sanhuang Xiexin Tang could significantly increase IL-10 production (p < 0.01) as well as decrease TNF-α production (p < 0.01). Macerated Sanhuang Xiexin Tang has a slightly higher anti-inflammatory effect than the Sanhuang Xiexin Tang decoction. Different preparation methods affected the pharmacokinetic characteristics and anti-inflammatory effects of Sanhuang Xiexin Tang's active constituents.

UPLC-ESI/MS determination of 17 active constituents in two categorized formulas of traditional Chinese medicine, Sanhuang Xiexin Tang and Fuzi Xiexin Tang: application in comparing the differences in decoctions and macerations.

A rapid and sensitive UPLC-ESI/MS method was established and validated to determine 17 active constituents (aconitine, hypaconitine, mesaconitine, benzoylaconine, benzoylhypaconine, benzoylmesaconine, berberine, palmatine, jatrorrhizine, coptisine, baicalein, wogonin, baicalin, wogonoside, emodin, aloe-emodin and rhein) in Sanhuang Xiexin Tang (SXT) and Fuzi Xiexin Tang (FXT), which are two classic compound recipes from Xiexin Tang categorized formulas in traditional Chinese medicien. The separation was performed on a UPLC BEH C18 column gradient eluted using acetonitrile and 0.1% formic acid as mobile phase. ESI/MS was operated in positive ([M + H](+)) in selected ion recording mode for analysis of alkaloids and flavones, while in negative ([M - H](-)) selected ion recording mode for anthraquinones. All of the 17 constituents exhibited good linearity in a relatively wide concentration ranges with the lowest limits of detection of 0.38 ng/mL. All of the relative standard deviation values of intra- and inter-precisions and stabilities of 17 constituents were within 5%. The method was successfully applied to determine 17 active constituents in decoctions and macerations of SXT and FXT. The results indicated that different preparative methods resulted in significant diversity in concentrations of the 17 analytes. Herb-herb interaction appeared between aconitum alkaloids in Aconiti Lateralis Radix Preparata and another three herbs.

Simultaneous determination of eleven major components in Fugan Fang using high-performance liquid chromatography coupled with mass spectrometry.

Fugan fang (FGF) is a traditional Chinese medicine (TCM) prescription that has been used in treating hepatic illnesses for many years. In this study, an analytical method is developed for the quantitative analysis of the major components of FGF. This method is based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS) on a reverse-phase C18 column. Results show that 0.01% acetic acid and acetonitrile is the optimum mobile phase in gradient elution. All compounds showed good linearity (r(2) ≥ 0.9948). Recoveries measured at three concentration levels varied from 83.5 to 104.8%. The method was validated with respect to precision, repeatability and accuracy and was successfully applied in the quantification of the 11 components of FGF products. The validated HPLC-MS method provides a basis for assessing the quality of TCM prescriptions containing many bioactive components.

[Absorption and pharmacokinetics of radix rehmanniae in rats].

In this paper, absorption and pharmacokinetic study of Radix Rehmanniae was studied by liquid chromatography coupled with mass spectrometry method after oral administration to rats. By comparing the chromatograms of ultraviolet, full scan, extracted ion and selective reaction monitoring (SRM) of standard solution, Radix Rehmanniae, blank plasma and rat plasma post drug administration, catalpol and ajugol were found to be the main compounds absorbed from Radix Rehmanniae. Plasma concentrations of aucubin, dihydrocatalpol, rehmannioside A (or rehmannioside B/ melittoside) and rehmannioside D were very low. Quantitative method for catalpol and aucubin and semi-quantitative method for other compounds in rat plasma were established. The pharmacokinetic study of those absorbed components was conducted after oral administration of 6 g x kg(-1) Radix Rehmanniae water extract to rats. Cmax, t(1/2) and AUC(0-infinity) of catalpol and ajugol were (2349.05 +/- 1438.34) and (104.25 +/- 82.05) ng x mL(-1), (0.86 +/- 0.32) and (0.96 +/- 0.37) h, (4407.58 +/- 2734.89) and (226.66 +/- 188.38) ng x h x mL(-1), respectively. tmax was at 1.00 h for catalpol and ajugol. Both catalpol and ajugol were absorbed and excreted rapidly.

Increased systemic exposure to rhizoma coptidis alkaloids in lipopolysaccharide-pretreated rats attributable to enhanced intestinal absorption.

Rhizoma coptidis is a rhizome commonly used in traditional Chinese medicine. After oral administration of rhizoma coptidis extract, the plasma concentrations of its effective alkaloid constituents are so low that their systemic therapeutic actions cannot be explained. This study aimed to investigate the influence of lipopolysaccharide (LPS) on the pharmacokinetics of the rhizoma coptidis alkaloids. Pharmacokinetic experiments were performed with rats; both in vitro absorption and efflux experiments were carried out with everted rat gut sacs, whereas in vitro metabolism experiments were conducted with rat liver microsomes and intestinal S9 fractions. Mucosal changes were evaluated with light microscopy and transmission electron microscopy. The results showed that, in rat plasma, LPS pretreatment increased systemic alkaloid exposure. LPS pretreatment increased the in vitro absorption of the alkaloids and decreased their efflux. The efflux of vinblastine and rhodamine 123, P-glycoprotein substrates, also was decreased. The absorption of fluorescein isothiocyanate-labeled dextran (average molecular mass, 4 kDa), a gut paracellular permeability probe, was not influenced. Obvious damage was observed in the mucosa, but the tight junctions between epithelial cells remained intact. Intestinal, rather than hepatic, alkaloid metabolism was decreased. These findings indicated that LPS pretreatment increased systemic exposure to the alkaloids through enhancement of their absorption, which was related to decreased intestinal efflux and metabolism. The results add to the understanding of why rhizoma coptidis is active despite the low plasma concentrations of the rhizoma coptidis alkaloids measured in normal subjects and experimental animals.

[In vitro effect of banxiaxiexin-decoction and different combinations on the metabolic activities of baicalin and baicalein in rat liver microsomes].

OBJECTIVE: To study the metabolism kinetics of baicalin and baicalein from Scutellaria baicalensis in rat liver microsomes and compare the effect of Banxiaxiexin-Decoction with different combinations on the metabolic activities of the flavonoids (baicalin and baicalein). METHODS: An UPLC method was developed for determination of baicalin and baicalein in rat liver microsomes incubation system. The effect of Banxiaxiexin-Decoction and different combinations (pungent-swelling group, bitter-descending group, sweet-invigorating group) on the metabolic activities of the flavonoids was investigated by vivo-induction and vitro-incubation method. RESULTS: The elimination of the flavonoids was linear, and the metabolism of baicalin had significant eliminated linear within 60 min, baicalein within 10 min. The peak area showed good linear relation when baicalin and baicalein was the concentration of 0.5 - 25 microg/mL. Microsomal protein concentration had significant effect on the flavonoids metabolism with the gradient from 0.2 g/L to 1.0 g/L in their corresponding time, and showed linear elimination with the growth of the concentration. The metabolic rate of baicalein in the blank liver microsomes was bigger than that of baicalin. The effect on metabolic of baicalin and baicalein, comparing the blank group, all parts showed inhibition strongest among the combinations, bitter-descending group second of that, pungent-swelling group had no significant for both, and sweet-invigorating group was without inhibition for baicalin, no significant inhibition for baicalein. CONCLUSION: Banxiaxiexin-Decoction shows inhibition on the metabolic for baicalin and baicalein, and is stronger than other combinations. This provides important pharmacological basis for compound prescription reasonable and clinical compatibility which plays the effect of mutual promotion.

Yinchenzhufu decoction protects against alpha-naphthylisothiocyanate-induced acute cholestatic liver injury in mice by ameliorating disordered bile acid homeostasis and inhibiting inflammatory responses.

ETHNOPHARMACOLOGICAL RELEVANCE: Intrahepatic cholestasis is a common condition of many liver diseases with few therapies. Yinchenzhufu decoction (YCZFD) is a representative traditional Chinese herbal formula used for treating jaundice and liver disease. AIM OF THE STUDY: To investigate the hepatoprotective effect of YCZFD against cholestatic liver injury and reveal its potential mechanism. MATERIALS AND METHODS: Mice with alpha-naphthyl isothiocyanate (ANIT)-induced intrahepatic cholestasis were orally administered YCZFD at doses of 3, 6, and 12g crude drug/kg for 2 weeks followed by subsequent analyses. A serum metabolomics study was then performed to explore the different metabolites influenced by YCZFD using ultra-high-performance liquid chromatography coupled with linear ion trap-Orbitrap hybrid mass spectrometry (UPLC-LTQ-Orbitrap-MS/MS).The levels of individual bile acids in the serum, liver, and bile were determined by UPLC-MS/MS. The expression of metabolic enzymes, transporters, inflammatory factors, and cytokeratin-19 (CK-19) was determined by real-time PCR, western blotting, and immunohistochemistry. RESULTS: YCZFD administration decreased the serum biochemical indexes and ameliorated pathological damage, such as hepatic necrosis and inflammatory cell infiltration. Serum metabolomics revealed that the metabolites influenced by YCZFD were mainly associated with bile acid metabolism and inflammation. YCZFD administration effectively ameliorated the disordered bile acid homeostasis. The bile acid transporter, multidrug-resistance associated protein 2 (Mrp2), and the metabolic enzyme, cytochrome P450 2b10 (Cyp2b10), were upregulated in the YCZFD intervention group compared to those in the ANIT-induced group. YCZFD administration also significantly inhibited nuclear factor-κB (NF-κB) and its phosphorylation and decreased the expression of proinflammatory cytokines including tumor necrosis factor-α, interleukin-1ß, and intercellular adhesion molecule-1 in ANIT-induced cholestatic mice. Additionally, the level of CK-19 was lower in the YCZFD intervention group than in the ANIT-induced cholestatic mice. CONCLUSION: YCZFD administration ameliorated disordered bile acid homeostasis, inhibited NF-κB pathway-mediated inflammation, and protected the liver from bile duct injury. Therefore, YCZFD exerted a protective effect against cholestatic liver injury.

Protective effect of cultured bear bile powder against dimethylnitrosamine-induced hepatic fibrosis in rats.

Natural bear bile has been used for liver disease in East Asia for thousands of years. However, its use has restrictions. In the current study, the therapeutic effects and potential mechanisms of cultured bear bile powder (CBBP) against hepatic fibrosis were evaluated in a dimethylnitrosamine (DMN)-induced rat model. CBBP treatment significantly improved DMN-induced hepatic necrosis and inflammatory infiltration. Additionally, CBBP remarkably alleviated the increased hepatic collagen content and expression of alpha-smooth muscle actin. Serum metabolomics revealed that 14 serum metabolites, including docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were decreased in DMN-treated rats, which was reversed by CBBP. Pathway analyses revealed that the main metabolic pathways affected by CBBP were related to fatty acid biosynthesis and metabolism, and biosynthesis of unsaturated fatty acids. EPA and DHA are ligands of peroxisome proliferator activated receptors (PPARs). CBBP treatment significantly stimulated liver mRNA and protein expression of PPARα and PPARγ. CBBP also markedly increased liver expression of PPARα target genes, which are involved in fatty acid ß-oxidation, and down-regulated IL-6, a downstream inflammatory gene of PPARγ. In conclusion, CBBP has the potential to attenuate liver fibrosis and its mechanism involves the promotion of the liver expression of PPARα and PPARγ. Our results may help in the development of a novel substitute for bear bile and therapeutic strategies for fibrotic liver diseases.

Mitochondrial membrane potential played crucial roles in the accumulation of berberine in HepG2 cells.

Berberine is a natural alkaloid that has antineoplastic effects. However, in hepatoma cells like HepG2, the expressions of uptake transporters are minimal but efflux transporters are relatively high. Hence, how berberine enters and reaches a cytocidal concentration remains to be elucidated. In the present study, we revealed the accumulation mechanism of berberine in HepG2 cells. Cell organelles were isolated based on differential centrifugation; berberine concentration was measured using a liquid chromatography-tandem mass chromatography method or flow cytometry. Subcellular distribution of berberine was observed using a laser scanning confocal microscopy. The results showed that berberine was concentration-, temperature-, and time-dependently taken up and accumulated in HepG2 cells. Membrane drug transporters and cell membrane potential had limited effects in berberine uptake. However, qualitative and quantitative studies showed that berberine was enriched in the mitochondria; inhibition of mitochondrial membrane potential (MMP) by carbonyl cyanide 3-chlorophenylhydrazone (CCCP) significantly decreased the intracellular berberine by up to 70%. More importantly, MMP not only significantly enhanced berberine uptake driven by cell membrane potential (P<0.01) but also inhibited p-glycoprotein (P-gp)-mediated berberine efflux (P<0.01). In brief, our results for the first time showed that MMP played crucial roles in berberine accumulation in HepG2 cells.

Protective effect of herbal medicine Huangqi decoction against chronic cholestatic liver injury by inhibiting bile acid-stimulated inflammation in DDC-induced mice.

BACKGROUND: Huangqi decoction (HQD), a classic traditional herbal medicine, has been used for liver fibrosis, but its effect on intrahepatic chronic cholestatic liver injury remains unknown. PURPOSE: In the present study, we investigated the hepatoprotective effect of HQD and the underlying molecular mechanisms in 3, 5-diethoxycarbonyl-1, 4-dihydroxychollidine (DDC)-induced chronic cholestatic mice. METHODS: The DDC-induced cholestatic mice were administrated HQD for 4 or 8 weeks. Serum biochemistry and morphology were investigated. The serum and liver bile acid (BA) levels were detected by ultra performance liquid chromatography-tandem mass spectrometry. The liver expression of BA metabolizing enzymes and transporters, and inflammatory and fibrotic markers was measured by real-time polymerase chain reaction, western blotting, and immunohistochemistry. RESULTS: HQD treatment for 4 or 8 weeks ameliorated DDC-induced liver injury by improving impaired hepatic function and tissue damage. HQD treatment for 8 weeks further decreased the liver expression of cytokeratin 19, tumor growth factor (TGF)-ß, collagen I, and α-smooth muscle actin, and ameliorated ductular reaction and liver fibrosis. HQD markedly decreased the accumulation of serum and liver BA. The expression of BA-metabolizing enzymes, cytochrome P450 2b10 and UDP glucuronosyltransferase 1 A1, and multidrug resistance-associated protein 2, Mrp3, and Mrp4 involved in BA homeostasis was increased by 4 weeks of HQD treatment. The expression of BA uptake transporter Na+-taurocholate cotransporting polypeptide was decreased and that of Mrp4 was increased after 8 weeks of HQD treatment. Nuclear factor-E2-related factor-2 (Nrf2) was remarkably induced by HQD treatment. Additionally, HQD treatment for 8 weeks decreased the liver expression of inflammatory factors, interleukin (IL)-6, IL-1ß, tumor necrosis factor-α, monocyte chemoattractant protein-1, and intracellular adhesion molecule-1. HQD suppressed the nuclear factor (NF)-κB pathway. CONCLUSION: HQD protected mice against chronic cholestatic liver injury and biliary fibrosis, which may be associated with the induction of the Nrf2 pathway and inhibition of the NF-κB pathway, ameliorating BA-stimulated inflammation.