Inhibitory effect of flavonoids on multidrug and toxin extrusion protein 1 function: Implications for food/herb-drug interaction and drug-induced kidney injury.

Multidrug and toxin extrusion protein 1 (MATE1), an efflux transporter mainly expressed in renal proximal tubules, mediates the renal secretion of organic cationic drugs. The inhibition of MATE1 will impair the excretion of drugs into the tubular lumen, leading to the accumulation of nephrotoxic drugs in the kidney and consequently potentiating nephrotoxicity. Screening and identifying potent MATE1 inhibitors can predict or minimize the risk of drug-induced kidney injury. Flavonoids, a group of polyphenols commonly found in foodstuffs and herbal products, have been reported to cause transporter-mediated food/herb-drug interactions. Our objective was to investigate the inhibitory effects of flavonoids on MATE1 in vitro and in vivo and to assess the effects of flavonoids on cisplatin-induced kidney injury. Thirteen flavonoids exhibited significant transport activity inhibition (>50%) on MATE1 in MATE1-MDCK cells. Among them, the six strongest flavonoid inhibitors, including irisflorentin, silymarin, isosilybin, sinensetin, tangeretin, and nobiletin, markedly increased cisplatin cytotoxicity in these cells. In cisplatin-induced in vivo renal injury models, irisflorentin, isosilybin, and sinensetin also increased serum creatinine and blood urea nitrogen levels to different degrees, especially irisflorentin, which exhibited the most potent nephrotoxicity with cisplatin. The pharmacophore model indicated that the hydrogen bond acceptors at the 3, 5, and 7 positions may play a critical role in the inhibitory effect of flavonoids on MATE1. Our findings provide helpful information for predicting the potential risks of flavonoid-containing food/herb-drug interactions and avoiding the exacerbation of drug-induced kidney injury via MATE1 mediation.

Inhibitory interaction of flavonoids with organic anion transporter 3 and their structure-activity relationships for predicting nephroprotective effects.

The organic anion transporter 3 (OAT3), an important renal uptake transporter, is associated with drug-induced acute kidney injury (AKI). Screening and identifying potent OAT3 inhibitors with little toxicity in natural products, especially flavonoids, in reducing OAT3-mediated AKI is of great value. The five strongest OAT3 inhibitors from the 97 flavonoids markedly decreased aristolochic acid I-induced cytotoxicity and alleviated methotrexate-induced nephrotoxicity. The pharmacophore model clarified hydrogen bond acceptors and hydrophobic groups are the critical pharmacophores. These findings would provide valuable information in predicting the potential risks of flavonoid-containing food/herb-drug interactions and optimizing flavonoid structure to alleviate OAT3-related AKI.

Targeting the Subpocket Enables the Discovery of Thiadiazole-Pyridazine Derivatives as Glutaminase C Inhibitors.

As glutaminase C (GAC) has become an attractive target for cancer treatment by regulating glutaminolysis, thus, interest in GAC inhibitors has risen in recent years. Herein, a potential binding subpocket comprising basic residues was identified, and through extensive structure-activity relationship studies, promising inhibitors 11 and 39 were identified with robust GAC inhibitory activity and A549 cell antiproliferative activity. X-ray crystallography of the 11-GAC and 27-GAC complexes revealed a novel binding mode against GAC. The potency of 11 and 27 against GACK320A further highlighted the importance of the binding. Notably, compounds 11 and 39 regulated the cellular metabolite, thereby increasing reactive oxygen species by blocking glutamine metabolism. Compound 11 also exhibited excellent antiproliferative activity in the A549 cell xenograft model. We further proved that 11 is a safe GAC allosteric inhibitor. A basic subpocket is proposed that might provide new strategies for the development of novel GAC inhibitors in the future.

A synthetic derivative of bioactive constituents from Isatis indigotica ameliorates hypersensitivity and arthritis by inhibiting JAK2-STAT3 pathway in mice.

The JAK-STAT pathway plays a crucial role in the signaling cascade associated with various cytokines that have been implicated in the pathogenesis of inflammatory diseases and myeloproliferative neoplasms (MPN). Among the isoforms of JAKs, the JAK2 subtype is primarily responsible for the function of hematopoietic system cells, making it a significant target in the treatment of MPN. However, the precise regulatory role of JAK2 in inflammatory diseases requires further investigation and confirmation. The current study employed a selective JAK2 inhibitor, ZT55, derived from Isatis indigotica roots, to examine its regulatory effects on inflammatory and immune responses in delayed-type hypersensitivity (DTH) and arthritis in mice. To evaluate the efficacy of ZT55 treatment, DNFB-induced DTH and collagen-induced arthritis (CIA) mouse models were utilized. T cells were cultured and subsequently analyzed for proliferation and activation using flow cytometry and EdU assay. Additionally, the maturation and function of dendritic cells were assessed through flow cytometry and ELISA. Our findings indicate that ZT55 significantly reduced DNFB-induced DTH and attenuated inflammation, cartilage degradation, and bone destruction in CIA mice. Moreover, ZT55 was found to inhibit the proliferation and activation of T cells and the maturation of dendritic cells by regulating the JAK2-STAT3 signaling pathway. These results suggest that selectively targeting the JAK2 isoform could have anti-inflammatory and immunosuppressive effects by regulating the adaptive and innate immune responses via the JAK2-STAT3 signaling pathway. Therefore, ZT55 has the potential to be a promising pharmaceutical candidate for the treatment of inflammatory and autoimmune diseases.

Inhibitory effects of flavonoids on glucose transporter 1 (GLUT1): From library screening to biological evaluation to structure-activity relationship.

Glucose transporter 1 (GLUT1) is mainly responsible for glucose uptake and energy metabolism, especially in the aerobic glycolysis process of tumor cells, which is closely associated with the advancement of tumors. Numerous studies have demonstrated that the inhibition of GLUT1 can decrease the growth of tumor cells and enhance drug sensitivity, so GLUT1 is considered to be a promising therapeutic target for cancer treatment. Flavonoids are a group of phenolic secondary metabolites present in vegetables, fruits, and herbal products, some of which were reported to increase cancer cells' sensitivity to sorafenib by inhibiting GLUT1. Our objective was to screen potential inhibitors of GLUT1 from 98 flavonoids and assess the sensitizing effect of sorafenib on cancer cells. and illuminate the structure-activity relationships of flavonoids with GLUT1. Eight flavonoids, including apigenin, kaempferol, eupatilin, luteolin, hispidulin, isosinensetin, sinensetin, and nobiletin exhibited significant inhibition (>50%) on GLUT1 in GLUT1-HEK293T cells. Among them, sinensetin and nobiletin showed stronger sensitizing effects and caused a sharp downward shift of the cell viability curves in HepG2 cells, illustrating these two flavonoids might become sensitizers to enhance the efficacy of sorafenib by inhibiting GLUT1. Molecular docking analysis elucidated inhibitory effect of flavonoids on GLUT1 was related to conventional hydrogen bonds, but not Pi interactions. The pharmacophore model clarified the critical pharmacophores of flavonoids inhibitors are hydrophobic groups in 3'positions and hydrogen bond acceptors. Thus, our findings would provide useful information for optimizing flavonoid structure to design novel GLUT1 inhibitors and overcome drug resistance in cancer treatment.

Structure-activity relationship study of amidobenzimidazole derivatives as stimulator of interferon genes (STING) agonists.

Stimulator of interferon genes (STING) is a crucial adaptor protein that can regulate the innate immune response by inducing the secretion of type Ι interferons and other cytokines after recognizing endogenous or exogenous DNA. Due to the key role of STING in the innate immune system, the activation of STING pathway is expected to be an efficacious immunotherapeutic tactic to treat cancer. In this study, we performed a structure-activity relationship study of amidobenzimidazole monomer, led to a series of ABZI STING agonist derivatives with potent STING-activating effects. Among them, compound 72, as a representative compound, markedly activated the STING-TBK1-IRF3 signaling pathway and significantly increased the mRNA and protein levels of IFN-ß, CXCL10 and IL-6 in both WT THP-1 cells and human peripheral blood mononuclear cells (hPBMCs). In addition, it was confirmed that compound 72 was highly selective for human STING, specifically targeting human STING signaling and showing no activation of m-STING.

Simultaneous determination of NTB-3119, a novel anti-tuberculosis agent, and its major metabolites in mouse plasma by LC-MS/MS and its application in preclinical pharmacokinetics study.

NTB-3119, a novel benzothiopyranone derivative, has been developed as a potential anti-tuberculosis(TB) drug with strong activity. In this study, three major metabolites of NTB-3119 were firstly identified in vitro and in vivo. A sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established for the quantitative analysis of NTB-3119 and its major metabolites NTB-3190, NTB-3202 and NTB-3204 in mouse plasma. The plasma samples were processed by protein precipitation with organic solvent. NTB-3119, NTB-3190, NTB-3202, NTB-3204 and NTB-4A (Internal Standard, IS) were separated by a Zorbax-SB C18 column (100 mm × 2.1 mm, 3.5 µm) with a gradient mobile phase of acetonitrile/water at a flow rate of 0.25 mL/min. The analytes were detected by electrospray positive ion mode in Parallel Reaction Monitoring (PRM) mode on a high resolution mass spectrum (HRMS, Thermo Q Executive). The monitored transitions were m/z 456.15632 → 360.06137 for NTB-3119, m/z 426.18214 → 246.01891 for NTB-3190, m/z 472.15124 → 360.06143 for NTB-3202, m/z 442.17706 → 246.01903 for NTB-3204 and m/z 337.13691 → 163.02081 for NTB-4A, respectively. Good linearity was conducted in the range of 5-2000 ng/mL for NTB-3119, NTB-3202 and NTB-3204 as well as 2.5-1000 ng/mL for NTB-3190. The inter- and intra-batch precision (RSD%) were both lower than 13.3 %, with the accuracy ranged from 88.0 % to 108.1 %. The analytes were proved to be stable during all samples storage, preparation and analytic procedures. The validated method was successfully applied to study the pharmacokinetics and bioavailability of NTB-3119 after oral treatment in Balb/c mouse.

Quantification of 2-NBDG, a probe for glucose uptake, in GLUT1 overexpression in HEK293T cells by LC-MS/MS.

The growth and proliferation of most cancer cells involve the excessive uptake of glucose mediated by glucose transporters. An effective strategy for cancer therapy has been to inhibit the GLUTs that are usually overexpressed in a variety of tumor cells. 2-NBDG is a GLUT1 substrate that can be used as a probe for GLUT1 inhibitors. An accurate and simple assay for 2-NBDG in a HEK293T cell model overexpressing GLUT1 was developed using liquid chromatography-tandem mass spectrometry. Chromatographic separation was achieved using a Xbridge® Amide column (3.5 µm, 2.1 mm × 150 mm, Waters) with acetonitrile-water containing 2 µM ammonium acetate (80:20, v/v) at a flow rate of 0.25 mL/min. Mass detection was conducted in the parallel reaction monitoring (PRM) mode. The calibration curve for 2-NBDG showed good linearity in the concentration range of 5-500 ng/mL with satisfactory precision, a relative standard deviation ranging from 2.92 to 9.59% and accuracy with a relative error ranging from -13.14 to 7.34%. This method was successfully applied to quantify the uptake of GLUT1-mediated 2-NBDG, and the results clearly indicated inhibition of GLUT1 by WZB117 and quercetin (two potent glucose transporter inhibitors) in the GLUT1-HEK293T cell model. This study provides a convenient and accurate method for high-throughput screening of selective and promising GLUT1 inhibitors.

Oral SMEDDS promotes lymphatic transport and mesenteric lymph nodes target of chlorogenic acid for effective T-cell antitumor immunity.

BACKGROUND: Mesenteric lymph nodes (MLNs) are critical draining lymph nodes of the immune system that accommodate more than half of the body's lymphocytes, suggesting their potential value as a cancer immunotherapy target. Therefore, efficient delivery of immunomodulators to the MLNs holds great potential for activating immune responses and enhancing the efficacy of antitumor immunotherapy. Self-microemulsifying drug delivery systems (SMEDDS) have attracted increasing attention to improving oral bioavailability by taking advantage of the intestinal lymphatic transport pathway. Relatively little focus has been given to the lymphatic transport advantage of SMEDDS for efficient immunomodulators delivery to the MLNs. In the present study, we aimed to change the intestinal lymphatic transport paradigm from increasing bioavailability to delivering high concentrations of immunomodulators to the MLNs. METHODS: Chlorogenic acid (CHA)-encapsulated SMEDDS (CHA-SME) were developed for targeted delivery of CHA to the MLNs. The intestinal lymphatic transport, immunoregulatory effects on immune cells, and overall antitumor immune efficacy of CHA-SME were investigated through in vitro and in vivo experiments. RESULTS: CHA-SME enhanced drug permeation through intestinal epithelial cells and promoted drug accumulation within the MLNs via the lymphatic transport pathway. Furthermore, CHA-SME inhibited tumor growth in subcutaneous and orthotopic glioma models by promoting dendritic cell maturation, priming the naive T cells into effector T cells, and inhibiting the immunosuppressive component. Notably, CHA-SME induced a long-term immune memory effect for immunotherapy. CONCLUSIONS: These findings indicate that CHA-SME have great potential to enhance the immunotherapeutic efficacy of CHA by activating antitumor immune responses.

Simultaneous determination of a novel oxazolidinone anti-tuberculosis OTB-658 and its metabolites in monkey blood by LC-MS/MS.

OTB-658, a novel oxazolidinone anti-tuberculosis agent, has potent antibacterial activity against Mycobacterium tuberculosis, especially multi-drug resistant tuberculosis (MDR-TB) in vitro and in vivo. In this study, after metabolite identification of parent drug OTB-658, a specific and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established and validated to quantify OTB-658 and its metabolites OTB-665 and OTB-698 in monkey blood. HHY-1442, an analogue compound of OTB-658, was used as the internal standard. Blood samples were prepared by direct protein precipitation. Separation was performed on a Zorbax SB C18 column (50 mm × 2.1 mm, 3.5 µm) with a gradient mobile phase of methanol/water at a flow rate of 0.3 mL/min. The detection was conducted by a positive electrospray ionization in multiple-reaction monitoring mode on a triple quadrupole MS. The monitored transitions were m/z 382.2 â†’ 221.1 for OTB-658, m/z 398.2 â†’ 308.1 for OTB-665, m/z 414.1 â†’ 372.3 for OTB-698 and m/z 418.2 â†’ 311.3 for HHY-1442, respectively. Good linearity was observed over the range of 10-2000 ng/mL for OTB-658 and OTB-665, and 5-1000 ng/mL for OTB-698. All the intra-day and inter-day precision for the three analytes was below 8.4%, and the accuracy ranged from 96.0% to 106.0%. All analytes were stable during storage, preparation, and analytical procedures. The validated method was successfully applied to pharmacokinetic and bioavailability studies of OTB-658 in cynomolgus monkeys and the absolute bioavailability of OTB-658 was 25.0% at an oral dose of 10 mg/kg.

Drug interaction study of flavonoids toward OATP1B1 and their 3D structure activity relationship analysis for predicting hepatoprotective effects.

Organic anion transporting polypeptide 1B1 (OATP1B1), a liver-specific uptake transporter, was associated with drug induced liver injury (DILI). Screening and identifying potent OATP1B1 inhibitors with little toxicity is of great value in reducing OATP1B1-mediated DILI. Flavonoids are a group of polyphenols ubiquitously present in vegetables, fruits and herbal products, some of them were reported to produce transporter-mediated DDI. Our objective was to investigate potential inhibitors of OATP1B1 from 99 flavonoids, and to assess the hepatoprotective effects on bosentan induced liver injury. Eight flavonoids, including biochanin A, hispidulin, isoliquiritigenin, isosinensetin, kaempferol, licochalcone A, luteolin and sinensetin exhibited significant inhibition (>50 %) on OATP1B1 in OATP1B1-HEK293 cells, which reduced the OATP1B1-mediated influx of methotrexate, accordingly decreased its cytotoxicity in OATP1B1-HEK293 cells and increased its AUC0-t in different extents in rats, from 28.27%-82.71 %. In bosentan-induced rat liver injury models, 8 flavonoids reduced the levels of serum total bile acid (TBA) and the liver concentration of bosentan in different degrees. Among them, kaempferol decreased the concentration most significantly, by 54.17 %, which indicated that flavonoids may alleviate bosentan-induced liver injury by inhibiting OATP1B1-mediated bosentan uptake. Furthermore, the pharmacophore model indicated the hydrogen bond acceptors and hydrogen bond donors may play critical role in the potency of flavonoids inhibition on OATP1B1. Taken together, our findings would provide helpful information for predicting the potential risks of flavonoid-containing food/herb-drug interactions in humans and alleviating bosentan -induced liver injury by OATP1B1 regulation.

Simultaneous determination of a promising anti-brain tumor agent CAT3 and its two major metabolites in mouse plasma and brain by a LC-MS/MS method.

A rapid and reproducible method with high selectivity was developed for simultaneous determination of a promising anti-brain tumor agent CAT3 and its two metabolites PF403 and GLU-PF403 in mouse plasma and brain. An economic deproteinization with septuple acetonitrile (v/v) was applied to pretreat the samples in this study. All analytes were well retained and separated on a CAPCELL CORE PC (2.7 µm, 2.1 mm I.D. × 150 mm, SHISEIDO Technologies) column with an eluting solvent of acetonitrile /water containing 0.1 % formic acid (v/v) at the flow rate of 0.2 mL per minute. The detection was carried out on a Q Exactive high resolution mass spectrometer equipped with a HESI ion source in parallel reaction monitoring (PRM) mode. The corresponding transitions for quantitation were 434.23→ 70.07 for CAT3, 350.17→70.07 for PF403, 526.21→70.07 for GLU-PF403, 364.19→70.07 for IS-1 and 625.18→317.07 for IS-2, respectively. A well-linear fit curve was achieved among the range of 0.1∼50 ng/mL for CAT3, 0.2∼100 ng/mL for PF403 and 2.5∼600 ng/mL for GLU-PF403 both in mouse plasma and brain homogenate. The intra-/inter-day accuracies of three analytes were within ±14.5 % and precisions were below to 13.44 %. The mean values of recovery of three compounds in mouse plasma and brain homogenate were among 98.06 ∼ 118.63 % and 81.04∼108.69 %. The analytes in NaF-treated ice cold blood of mouse was stable within tested 30 min. Plasma and brain homogenate samples had no obvious changes during all storage, sample treatment and analytic process of mouse plasma sample. The reproducible and reliable method was well employed to the research of CAT3 pharmacokinetic characteristics in mouse plasma and brain after a single intragastric administration at dose of 10 mg/kg.

Evaluation of inhibitory effects of flavonoids on breast cancer resistance protein (BCRP): From library screening to biological evaluation to structure-activity relationship.

Flavonoids are a group of polyphenols ubiquitously present in vegetables, fruits and herbal products, despite various known pharmacological activities, few researches have been done about the interaction of flavonoids with breast cancer resistance protein (BCRP). The present study was designed to investigate the inhibitory effects of 99 flavonoids on BCRP in vitro and in vivo and to clarify structure-activity relationships of flavonoids with BCRP. Eleven flavonoids, including amentoflavone, apigenin, biochanin A, chrysin, diosimin, genkwanin, hypericin, kaempferol, kaempferide, licochalcone A and naringenin, exhibited significant inhibition (>50%) on BCRP in BCRP-MDCKII cells, which reduced the BCRP-mediated efflux of doxorubicin and temozolomide, accordingly increased their cytotoxicity. In addition, co-administration of mitoxantrone with the 11 flavonoids increased the AUC0-t of mitoxantrone in different extents in rats. Among them, chrysin increased the AUC0-t most significantly, by 81.97%. Molecular docking analysis elucidated the inhibition of flavonoids on BCRP might be associated with Pi-Pi stacked interactions and/or potential Pi-Alkyl interactions, but not conventional hydrogen bonds. The pharmacophore model indicated the aromatic ring B, hydrophobic groups and hydrogen bond acceptors may play critical role in the potency of flavonoids inhibition on BCRP. Thus, our findings would provide helpful information for predicting the potential risks of flavonoid-containing food/herb-drug interactions in humans.

Inhibitory effects of flavonoids on P-glycoprotein in vitro and in vivo: Food/herb-drug interactions and structure-activity relationships.

Flavonoids are a class of polyphenol antioxygen, despite various known biological activities and therapeutic potential, scattered but not much is known about their interactions with drug transporters. P-glycoprotein (P-gp) as a cellular defense mechanism by effluxing its substrates has been widely investigated. The aim of this study was to investigate the inhibitory effects of 75 flavonoids on P-gp in vitro and in vivo and to illuminate the structure-activity relationships of flavonoids with P-gp. Five flavonoids, including tangeretin, sinensetin, isosinensetin, sciadopitysin and oroxylin A exhibited significant inhibition on P-gp in MDR1-MDCKIIcells, which reduced the P-gp-mediated efflux of paraquat and taxol and consequently increased their cell toxicity. In addition, co-administration of digoxin with five flavonoids increased the AUC0-t of digoxin in different extents in rats, from 19.84% to 81.51%. Molecular docking assays elucidated the inhibitory effect of flavonoids might be related to Pi interactions, but not hydrogen bonds. The pharmacophore model suggested the hydrophobic groups in B benzene ring may play a vital role in the potency of flavonoids inhibition on P-gp. Taken together, our findings would provide the basis for a reliable assessment of the potential risks of flavonoid-containing food/herb-drug interactions in humans.

Dendritic cells loaded with HeLa-derived exosomes simulate an antitumor immune response.

The aim of the present study was to investigate the effect of loading dendritic cells (DCs) with HeLa-derived exosomes on cytotoxic T-lymphocyte (CTL) responses, and the cytotoxic effects of CTL responses on the HeLa cell line. Ultrafiltration centrifugation combined with sucrose density gradient ultracentrifugation was applied to isolate exosomes (HeLa-exo) from the supernatant of HeLa cells. Morphological features of HeLa-exo were identified by transmission electron microscopy (TEM), and the expression of cluster of differentiation (CD)63 was detected by western blotting. Next, monocytes were isolated from peripheral blood and cultured with the removal of adherent cells to induce DC proliferation. DCs were then phenotypically characterized by flow cytometry. Finally, MTT assays were performed to analyze the effects of DCs loaded with HeLa-exo on T cell proliferation and cytotoxicity assays to evaluate the effect of CTL responses on HeLa cells. TEM revealed that HeLa-exo exhibit typical cup-shaped morphology with a diameter range of 30-100 nm. It was also identified that the CD63 surface antigen is expressed on HeLa-exo. Furthermore, monocyte-derived DCs were able to express CD1a, suggesting that DC induction was a success. DCs exhibited hair-like protrusions and other typical dendritic cell morphology. Furthermore, DCs loaded with HeLa-exo could enhance CTL proliferation and the cytotoxic activity of CTLs compared with DCs without HeLa-exo (P<0.05). In conclusion, DCs loaded with HeLa-exo may promote T cell proliferation and induce CTL responses to inhibit the growth of cervical cancer cells in vitro.

Simultaneous quantification of 2',3',5'-tri-O-acetyl-N6-(3-hydroxylaniline)adenosine and its principal metabolites in hamster blood by LC-MS/MS and its application in pharmacokinetics study.

2',3',5'-Tri-O-acetyl-N6-(3-hydroxylaniline)adenosine (IMM-H007, once called WS070117) is being developed as a novel anti-hyperlipidemia agent for its high efficacy and low toxicity. In this study, a sensitive and specific liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was established for the simultaneous quantification of IMM-H007 and its two major metabolites (3S,4R,5R)-2-(hydroxymethyl)-5-(6-((3-hydroxyphenyl)amino)-9H-purin-9-yl)tetrahdrofuran-3,4-diol (M1) and ((2R,3S,4R,5R)-3,4-dihydroxy-5-(6-((3-hydroxyphenyl)amino)-9H-purin-9-yl)tetrahydrofuran-2-yl)methyl dihydrogen phosphate (MP) in hamster blood. An analogue of IMM-H007, WS070119 was used as the internal standard. Blood samples were prepared by a simple protein precipitation with acetonitrile. The chromatographic separation was performed on a ReproSil-Pur 120C18 column (3µm, 2mm×100mm) with a gradient mobile phase of methanol/water containing 0.1% formic acid (v/v) in a flow rate of 0.2mL/min. Detection was carried out on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization (ESI) in positive ion selective reaction monitoring (SRM) mode. The monitored transitions were 486.2→228.1 for IMM-H007, 360.0→228.0 for M1, 440.0→228.0 for MP and 374.1→242.0 for the internal standard, respectively. Satisfactory linearity was obtained for the analytes over the range of 1-500ng/mL for IMM-H007, 2-1000ng/mL for M1 and 10-5000ng/mL for MP. The lower limits of the quantification (LLOQs) were 1ng/mL for IMM-H007, 2ng/mL for M1 and 10ng/mL for MP. The intra-day and inter-day precisions (RSD, %) of the analytes were within 14.2%, and the accuracy (RE, %) ranged from -9.4% to 10.7%. The average recoveries of the analytes were more than 80.0%. The analytes were proved to be stable during given storage, preparation, and analytic procedures. The method was successfully applied to the pharmacokinetic study in hamsters after oral administration of IMM-H007.

Measures of reducing obstetric emergencies hysterectomy incidence.

To study the obstetric emergency hysterectomy which can reduce the incidence of measures. In maternity of Xinxiang Central Hospital, the total number of deliveries cases has been up to 50,526 in 20 years, of which 48 cases were retrospectively analyzed for the clinical data of Emergency uterine surgery cases. Cases underwent obstetric emergency hysterectomy accounted for 0.095% of total deliveries (48/50 526), in which 11 cases of vaginal delivery, 37 cases of cesarean section. The indications for surgery: 27 cases were cased by placental factors accounted for 56.25%; 14 cases of uterine inertia, accounting for 29.17%; uterine rupture in 4 cases, accounting for 8.33%; 3 cases of coagulopathy, accounting for 6.25%. Where the maternal placental factors hysterectomy is the most common (69.70%, 23/33) and the predominant factor is early maternal uterine inertia (60.00%, 9/15). There are 74.09% (20/27) of patients with placental abnormalities history of previous cesarean section or uterine surgery. The major risk factors leading to obstetric emergency hysterectomy is placental factors. Preventing the occurrence of placental abnormalities planting actively can effectively reduce the rate of obstetric hysterectomy.

Quantitative determination of 2-amino-2-(2-(4'-(2-propyloxazol-4-yl)-[1,1'-biphenyl]-4-yl)ethyl)propane-1,3-diol and its active phosphorylated metabolite in rat blood by LC-MS/MS and application to PK/PD analysis.

A sensitive and specific LC-MS/MS method was developed and validated for simultaneous determination of 2-amino-2-(2-(4'-(2-propyloxazol-4-yl)-[1,1'-biphenyl]-4-yl)ethyl)propane-1,3-diol (SYL930) and its active phosphate metabolite (SYL930-P) in rat blood using SYL927, an analogue of SYL930 as the internal standard. Blood samples were prepared by a simple protein precipitation with acetonitrile. The chromatographic separation was performed on a ZorbaxSB-C18 column (3.5 µm, 2.1 × 100 mm) with a gradient mobile phase of methanol/water containing 0.1 % formic acid (v/v) at a flow rate of 0.2 mL/min. The detection was carried out on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization (ESI) in multiple reactions monitoring mode (MRM). The monitored transitions were 381.2 → 364.2 for SYL930, 461.2 → 334.2 for SYL930-P, and 367.1 → 350.4 for the internal standard, respectively. Good linearity was obtained for the analytes over the range of 0.2-100 ng/mL for SYL930 and 0.5-100 ng/mL for SYL930-P. The lower limits of quantitation (LLOQs) for SYL930 and SYL930-P were 0.2 and 0.5 ng/mL, respectively. The intra-day and inter-day precisions (RSD, %) of analytes were within 9.87 %, and the accuracy (RE, %) ranged from -7.04 to 13.15 %. The mean recoveries for two compounds in rat blood were 87.9-109 %. The analytes were proved to be stable during all sample storage, preparation, and analytic procedures. The validated method was successfully applied to pharmacokinetic and PK/PD studies of SYL930 and SYL930-P in rats after oral administration of SYL930. Graphical Abstract Quantitative determination of SYL930 and its active phosphorylated metabolite in rat blood by LCMS/MS and application to PK/PD analysis.

[Advances in the pharmacological study of Morus alba L].

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.

Simultaneous quantification of MTC-220 and its metabolites in beagle dog plasma by liquid chromatography-tandem mass spectrometry.

A sensitive LC-ESI-MS/MS method for simultaneous determination of MTC-220 and its metabolites (paclitaxel and MDA-linker) in dog plasma has been developed and validated. After addition of docetaxel (internal standard), plasma samples containing MTC-220, paclitaxel and MDA-linker were prepared based on a simple protein precipitation by adding two volumes of acetonitrile. The separation was performed on a ZorbaxSB-C18 column (3.5µm, 2.1mm×100mm) at a flow rate of 0.2ml/min, using acetonitrile/water containing 0.1% formic acid (v/v) as mobile phase. The detection was performed on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization (ESI) by selected reaction monitoring (SRM). The MS/MS ion transit ions monitored were 1444.4→623.8 for MTC-220, 876.4→307.9 for paclitaxel, 631.2→531.2 for MDA-linker and 830.2→549.1 for the internal standard. Linear detection responses were obtained for MTC-220, paclitaxel and MDA-linker ranging from 10 to 5000, 5 to 2500 and 5 to 500ng/ml, respectively. The lower limits of quantitation (LLOQs) for MTC-220, paclitaxel and MDA-linker were 10, 5 and 5ng/ml, respectively. The intra-day and inter-day precisions (RSD, %) of the three analytes do not exceed 10.9% except for LLOQs (≤17.50), and the accuracy (RE, %) were within ±17.5% for LLOQs and ±12.6% for the others. The average recoveries of three compounds were greater than 85.0%. The analytes were proved to be stable during all sample storage, preparation and analytic procedures. The validated method was successfully applied to pharmacokinetic studies of MTC-220 and its metabolites in beagle dogs after intravenous infusion of MTC-220 at 2.5mg/kg.