Theranostic Fibers for Simultaneous Imaging and Drug Delivery.

New methods for creating theranostic systems with simultaneous encapsulation of therapeutic, diagnostic, and targeting agents are much sought after. This work reports for the first time the use of coaxial electrospinning to prepare such systems in the form of core-shell fibers. Eudragit S100 was used to form the shell of the fibers, while the core comprised poly(ethylene oxide) loaded with the magnetic resonance contrast agent Gd(DTPA) (Gd(III) diethylenetriaminepentaacetate hydrate) and indomethacin as a model therapeutic agent. The fibers had linear cylindrical morphologies with clear core-shell structures, as demonstrated by electron microscopy. X-ray diffraction and differential scanning calorimetry proved that both indomethacin and Gd(DTPA) were present in the fibers in the amorphous physical form. This is thought to be a result of intermolecular interactions between the different components, the presence of which was suggested by infrared spectroscopy. In vitro dissolution tests indicated that the fibers could provide targeted release of the active ingredients through a combined mechanism of erosion and diffusion. The proton relaxivities for Gd(DTPA) released from the fibers into tris buffer increased (r1 = 4.79-9.75 s(-1) mM(-1); r2 = 7.98-14.22 s(-1) mM(-1)) compared with fresh Gd(DTPA) (r1 = 4.13 s(-1) mM(-1) and r2 = 4.40 s(-1) mM(-1)), which proved that electrospinning has not diminished the contrast properties of the complex. The new systems reported herein thus offer a new platform for delivering therapeutic and imaging agents simultaneously to the colon.

Comprehensive metabolite profiling of Plantaginis Semen using ultra high performance liquid chromatography with electrospray ionization quadrupole time-of-flight tandem mass spectrometry coupled with elevated energy technique.

Plantaginis Semen is commonly used in traditional medicine to treat edema, hypertension, and diabetes. The commercially available Plantaginis Semen in China mainly comes from three species. To clarify the chemical composition and distinct different species of Plantaginis Semen, we established a metabolite profiling method based on ultra high performance liquid chromatography with electrospray ionization quadrupole time-of-flight tandem mass spectrometry coupled with elevated energy technique. A total of 108 compounds, including phenylethanoid glycosides, flavonoids, guanidine derivatives, terpenoids, organic acids, and fatty acids, were identified from Plantago asiatica L., P. depressa Willd., and P. major L. Results showed significant differences in chemical components among the three species, particularly flavonoids. This study is the first to provide a comprehensive chemical profile of Plantaginis Semen, which could be involved into the quality control, medication guide, and developing new drug of Plantago seeds.

Metabolic profiles of 20(S)-protopanaxadiol in rats after oral administration using ultra-performance liquid chromatography/quadrupole time-of-flight tandem mass spectrometry.

RATIONALE: 20(S)-Protopanaxadiol (PPD), a dammarane-type triterpenoid sapogenin, acts as the pharmacophore of ginsenosides which are considered as the principal bioactive components in Chinese ginseng. To fully understand the mechanism of action of PPD, it is important to study its metabolic profiles in vivo. METHODS: Plasma, urine, fece and bile were collected after administration of PPD formulated in 0.5% aqueous Tween-80 to rats (150 mg/kg). Samples were analyzed by using a sensitive and reliable method based on ultra-performance liquid chromatography/quadrupole time-of-flight tandem mass spectrometry (UPLC/Q-TOF-MS/MS) in both positive and negative ion mode. The chemical structures of metabolites were elucidated by comparing the retention time, accurate molecular mass, and fragmentation patterns of analytes with those of PPD. RESULTS: In total 29 metabolites, including 10 new metabolites (M20-M29), were tentatively identified and characterized. Among them, two metabolites (M3 and M4) were unambiguously identified by matching their retention times and fragmentation patterns with their standards. Principal metabolites, namely, 20, 24-oxide metabolites (M3 and M4), 26/27-carboxylic acid derivatives (M22 and M23) and a glucuronidated product (M28), were found in the rat plasma. CONCLUSIONS: The results showed that phase I metabolites are monooxygenation, dioxygenation and oxidative dehydrogenation metabolites, and phase II metabolic pathways were demonstrated to be cysteine conjugation and glucuronidation. The newly identified metabolites are useful to understand the mechanism of elimination of PPD and, in turn, its effectiveness and toxicity.

Quinolone alkaloids from Fructus Euodiae show activity against methicillin-resistant Staphylococcus aureus.

Fructus Euodiae is used in traditional Chinese medicine to treat infection. In this study, four of the quinolone alkaloids isolated from Fructus Euodiae showed activity against methicillin-resistant Staphylococcus aureus (MRSA). The minimum inhibitory concentrations (MIC) were 8-128 µg/mL, which were equivalent to or lower than the control antibiotics, oxacillin, erythromycin and tetracycline (MIC ≥128 µg/mL). Among these isolated quinolone alkaloids, evocarpine with a 13 carbon alkenyl chain substituent at position-2 showed the best activity against MRSA. This study has demonstrated the potential of quinolone alkaloids from Fructus Euodiae as anti-MRSA compounds and supports the traditional use of the fruit as a treatment for bacterial infections.

Characterization of two homogalacturonan pectins with immunomodulatory activity from green tea.

Two natural homogalacturonan (HG) pectins (MW ca. 20 kDa) were isolated from green tea based on their immunomodulatory activity. The crude tea polysaccharides (TPS1 and TPS2) were obtained from green tea leaves by hot water extraction and followed by 40% and 70% ethanol precipitation, respectively. Two homogenous water soluble polysaccharides (TPS1-2a and TPS1-2b) were obtained from TPS1 after purification with gel permeation, which gave a higher phagocytic effect than TPS2. A combination of composition, methylation and configuration analyses, as well as NMR (nuclear magnetic resonance) spectroscopy revealed that TPS1-2a and TPS1-2b were homogalacturonan (HG) pectins consisting of a backbone of 1,4-linked α-D-galacturonic acid (GalA) residues with 28.4% and 26.1% of carboxyl groups as methyl ester, respectively. The immunological assay results demonstrated that TPS1-2, which consisted mainly of HG pectins, showed phagocytosis-enhancing activity in HL-60 cells.

Debrisoquine metabolism and CYP2D expression in marmoset liver microsomes.

The objective of this study was to define CYP2D enzymes in marmoset (Callithrix jacchus) liver microsomes, both at the activity level using debrisoquine as the model substrate and at the protein level using antibodies raised to human CYP2D6. Marmoset liver microsomes were incubated with [(14)C]debrisoquine, and the structure of the generated metabolites was determined using liquid chromatography-tandem mass spectrometry and NMR. Marmoset liver microsomes were very effective in hydroxylating debrisoquine at various positions. Although 4-hydroxydebrisoquine was formed, in contrast to rat and human it was only a minor metabolite. Debrisoquine was more extensively hydroxylated in the 7, 5, 6, and 8 positions. In addition to the monohydroxylated metabolites, a dihydroxy metabolite, namely 6,7-dihydroxydebrisoquine, was identified. Finally, metabolites that had undergone ring opening were also detected but were not investigated further. Antibodies to CYP2D6 immunoreacted with protein in marmoset and human but not rat hepatic microsomes. In conclusion, we demonstrate that marmoset liver microsomes are effective in hydroxylating debrisoquine at various positions and that they contain a protein that is immunorelated to human CYP2D6.

Identification of metabolites of geniposide in rat urine using ultra-performance liquid chromatography combined with electrospray ionization quadrupole time-of-flight tandem mass spectrometry.

Geniposide, an iridoid glycoside, is an important and characteristic compound in the fruits of Gardenia jasminoides Ellis, a commonly used medicinal herb in Chinese traditional and folk medicine for the treatment of inflammation and jaundice. However, few studies have been carried out on the metabolism of geniposide. In this study, we have established a rapid and sensitive method using ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC/ESI-QTOF-MS) for analysis of the metabolic profile of geniposide in rat urine after oral administration. A total of ten metabolites were detected and identified by comparing their fragmentation patterns with that of geniposide using Metabolynx™ and MassFragment™ software tools. The results revealed that the principal metabolism pathways of geniposide in rat occurred after deglycosylation of the irdoid glycoside take place and this is followed by glucuronidation and the pyran-ring cleavages. The major metabolite, the glucuronic acid conjugate of genipin as observed in vivo, was further confirmed by the in vitro enzymatic study. The results of this work have demonstrated the feasibility of the UPLC/ESI-QTOF-MS approach for rapid and reliable characterization of metabolites from iridoid compounds.

Synthesis and characterisation of a novel tubulin-directed DO3A-colchicine conjugate with potential theranostic features.

Colchicine is a known tubulin binding agent enabling necrosis in tumors. A novel tubulin-directed DO3A-colchicine conjugate and its Gd(III) complex were prepared from N-deacetylcolchicine, coupling alkaloid and polyaza-alicyclic functions via a peptide coupling methodology. The longitudinal proton relaxivity of the Gd(III) complex in water at 4.7 T is 2.86 mM(-1) s(-1) and a similar efficacy as colchicine towards ovarian carcinoma cells in vitro.

Improving polymer nanofiber quality using a modified co-axial electrospinning process.

Based on a modified coaxial electrospinning process and suitable selection of solvent mixtures as sheath fluid, a new strategy is presented for systematically improving polymer nanofiber quality. A concentric spinneret with an indented inner capillary is designed for the modified coaxial electrospinning. With a solution of 12% w/v PVP K60 in ethanol as the core electrospinning fluid, six solvents are used as sheath fluids to investigate the impact of solvent properties on the resultant PVP nanofiber quality. The PVP nanofiber quality is closely related to solvent physical-chemical properties. High quality PVP nanofibers of average diameter 130 ±10 nm with homogeneous structures and smooth surfaces are created using a solvent mixture of acetone, ethanol and DMAc in the ratio of 3:1:1(v/v/v).

Acetate Induces Growth Arrest in Colon Cancer Cells Through Modulation of Mitochondrial Function.

Acetate is one of the main short chain fatty acids produced in the colon when fermentable carbohydrates are digested. It has been shown to affect normal metabolism, modulating mitochondrial function, and fatty acid oxidation. Currently, there is no clear consensus regarding the effects of acetate on tumorigenesis and cancer metabolism. Here, we investigate the metabolic effects of acetate on colon cancer. HT29 and HCT116 colon cancer cell lines were treated with acetate and its effect on mitochondrial proliferation, reactive oxygen species, density, permeability transition pore, cellular bioenergetics, gene expression of acetyl-CoA synthetase 1 (ACSS1) and 2 (ACSS2), and lipid levels were investigated. Acetate was found to reduce proliferation of both cell lines under normoxia as well as reducing glycolysis; it was also found to increase both oxygen consumption and ROS levels. Cell death observed was independent of ACSS1/2 expression. Under hypoxic conditions, reduced proliferation was maintained in the HT29 cell line but no longer observed in the HCT116 cell line. ACSS2 expression together with cellular lipid levels was increased in both cell lines under hypoxia which may partly protect cells from the anti-proliferative effects of reversed Warburg effect caused by acetate. The findings from this study suggest that effect of acetate on proliferation is a consequence of its impact on mitochondrial metabolism and during normoxia is independent of ACCS1/2 expression.

HPLC fingerprints combined with principal component analysis, hierarchical cluster analysis and linear discriminant analysis for the classification and differentiation of Peganum sp. indigenous to China.

INTRODUCTION: Seeds of wild Peganum harmala Linn., P. multisectum (Maxim) Bobr., P. nigellastrum Bunge and a probable indeterminate species, herein referred to as P. variety, are commonly used in Chinese medicine. These seeds cannot be differentiated based on morphology. OBJECTIVE: Seeds of P. harmala Linn., P. multisectum (Maxim) Bobr., P. nigellastrum Bunge and P. variety were collected in different provinces in China and their HPLC profiles were recorded for statistical analysis and pattern recognition.Methodology - HPLC chromatograms of seed extracts were recorded under the same conditions. Individual HPLC chromatograms for each species were evaluated against the mean chromatogram for the same species generated using a similarity evaluation computer program. Data from chromatographic fingerprints were also processed using principal component analysis (PCA), hierarchical cluster analysis (HCA) and linear discriminant analysis (LDA). RESULTS: The Peganum sp. seed extracts had similar HPLC fingerprints but with some inter-specific differences. The chromatographic fingerprints combined with PCA, HCA and LDA could distinguish the seeds of the different species of Peganum investigated. CONCLUSION: HPLC fingerprints can be used to authenticate and differentiate the seeds of three different species of genus Peganum indigenous to China. The results indicated that the unidentified P. variety might indeed be a new species or variety.

Comparative study of electrospun crystal-based and composite-based drug nano depots.

Complex nanostructures are increasingly becoming important in the development of novel functional nanomaterials. Nano drug depots, characterized by core-shell structures with core drug reservoirs, are drawing increasing attention because of its potential applications in furnishing drug-sustained release profiles. In the present study, two kinds of nano drug depots, one containing a crystal drug reservoir and the other having a medicated composite drug reservoir, were prepared through modified triaxial electrospinning. Their drug-sustained release performances were compared in terms of initial burst release, middle linear release, and the late tailing off release. Although both depots had a linear morphology, clear core-shell nanostructures and the same cellulose acetate shell layer, they provided considerably different tailing off release performances, and thus different sustained release profiles. The composite-based drug depots showed a smaller tailing off drug amount of 2.2%, a shorter time period of 12 h, and a better zero-order controlled release kinetics in general than the crystal-based drug depots, whose tailing off amount was 9.3% over a time period of 36 h. The mechanism was proposed, which had a close relationship with the state of drug in the core reservoir. The present protocols open a new way for producing medicated structural nanomaterials.

Identification of metabolites of adonifoline, a hepatotoxic pyrrolizidine alkaloid, by liquid chromatography/tandem and high-resolution mass spectrometry.

Hepatotoxic pyrrolizidine alkaloid (HPA)-containing plants have always been a threat to human and livestock health worldwide. Adonifoline, a main HPA in Senecio scandens Buch.-Ham. ex D. Don (Qianli guang), was used officially as an infusion in cases of oral and pharyngeal infections in China. In this study in vivo metabolism of adonifoline was studied for the first time by identifying the metabolites of adonifoline present in bile, urine and feces of rats using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS(n)) (ion trap) as well as liquid chromatography/electrospray ionization high-resolution mass spectrometry (LC/ESI-HRMS) (quadrupole-time of flight). In total 19 metabolites were identified and, among them, retronecine-N-oxides were confirmed by matching their fragmentation patterns with their fully characterized synthetic compounds. These metabolites are all involved in both phase I and phase II metabolic processes and the principal in vivo metabolism pathways of adonifoline were proposed.

Oral fast-dissolving drug delivery membranes prepared from electrospun polyvinylpyrrolidone ultrafine fibers.

Oral fast-dissolving drug delivery membranes (FDMs) for poorly water-soluble drugs were prepared via electrospinning technology with ibuprofen as the model drug and polyvinylpyrrolidone (PVP) K30 as the filament-forming polymer and drug carrier. Results from differential scanning calorimetry, x-ray diffraction, and morphological observations demonstrated that ibuprofen was distributed in the ultrafine fibers in the form of nanosolid dispersions and the physical status of drug was an amorphous or molecular form, different from that of the pure drug and a physical mixture of PVP and ibuprofen. Fourier-transform infrared spectroscopy results illustrated that the main interactions between PVP and ibuprofen were mediated through hydrogen bonding. Pharmacotechnical tests showed that FDMs with different drug contents had almost the same wetting and disintegrating times, about 15 and 8 s, respectively, but significantly different drug dissolution rates due to the different physical status of the drug and the different drug-release-controlled mechanisms. 84.9% and 58.7% of ibuprofen was released in the first 20 s for FDMs with a drug-to-PVP ratio of 1:4 and 1:2, respectively. Electrospun ultrafine fibers have the potential to be used as solid dispersions to improve the dissolution profiles of poorly water-soluble drugs or as oral fast disintegrating drug delivery systems.

Organophosphorus compounds: intervention in mechanisms of signal transduction relevant to proliferative, immunological and circulatory disorders.

Literature publications reporting the development of organophosphorus compounds, targeting aspects of signal transduction to the titled therapeutic ends, are reviewed. With respect to extracellular targets, the development of ligands to purinergic (P2), and endothelial differentiation-gene receptors (of S1P- and LPA-receptor subtypes) is charted, along with inhibitors of the production and release of tumour necrosis factor-alpha (TNF-alpha). Reported also are inhibitors of the ectoenzymes aminopeptidase N, aminopeptidase A and dipeptidyl peptidase IV, the proteolytic enzyme thrombin, ligands to "apoptosis-receptors" and gammadelta T-cell activators. In addition, disruption of intracellular signalling chains mediated through reversible coupling of proteins via phosphorylation of Tyr residues and docking of pTyr residues in SH2-binding domains is covered. In particular, the development of ligands to SH2-binding domains in tyrosine kinases Src and lck, adaptor protein Grb2, and also ZAP70 protein are reported along with inhibitors to relevant phosphatases. SAR studies of ligands to Ins(1,4,5)-P3- and ryanodine-type receptors of intracellular Ca2+-storage organelles are described including analogues to secondary messengers cyclic-ADP-ribose (cADPR) and myo-inositol-1,4,5-triphosphate. Inhibitors of phosphatidyl inositol 3-kinase (PI3K) and sphingomyelinase are also reported, as are inhibitors of farnesyl transferase, the enzyme involved in protein-prenylation.

Cytotoxic sesquiterpenes from Ligularia platyglossa.

Four sesquiterpene lactones including an eremophilenolide dimer, named as biligulaplenolide, 1, 8beta-hydroxy-1-oxo-(14alpha,15alpha eremophil-7(11),9(10)-dien-12,8alpha-olide, 2, 1-hydroxy-2-oxo-(14alpha,15alpha eremophil-1(10),7(11),8(9)-trien-12,8-olide, 3, 4alpha,8beta,9alpha-trihydroxy- 5alphaEta-7(11)-eudesmen-12,8alpha-olide, 4, along with two known ones, 10alpha-hydroxy-1-oxo-eremophil-7(11),8(9)-dien-12,8-olide, 5, and furanoeremophil-1(10)-ene-2,9-dione, 6, were isolated from the underground organs of Ligularia platyglossa (Franch.) Hand.-Mazz. Their structures were elucidated by spectroscopic methods including single-crystal X-ray diffraction analysis (2 and 3). Their in vitro cytotoxicities against seven cancer cell lines (BGC-823, A549, HL-60, B16, SMMC-7721, BEL7402, Hela) were evaluated. Compounds 2, 3, 5 showed cytotoxic activities on HL-60 cancer cells with IC50 in the range of 24.0 to 51.1 microM, whereas compound 3 exhibited only weak cytotoxic activity against the B16, BEL7402 and Hela cancer cells. Flow cytometric analysis indicated that compound 3 induces Hela cells to apoptotic death after 48 h treatment with 0.38 mM of this compound.

Sulfated beta-glucan derived from oat bran with potent anti-HIV activity.

China is a major producer of oats; the annual harvested area of 350,000 ha yields approximately 465,000 tons, giving an average yield of 1.33 tons/ha. The bran is not used for animal feed as it is of poor digestibility and low nutritive content and is considered a waste byproduct. Therefore, it is advantageous to produce a value-added product from the bran. We extracted the native polysaccharide, a linear (1-3)-, (1-4)-linked beta-glucan (OBG) from the oat bran and synthesized a sulfated derivative OBGS containing 36.5% sulfate. OBGS had potent activity against a primary isolate of human immunodeficiency virus (HIV-1) in peripheral blood mononuclear cells at a concentration (EC(50)=5.98 x 10(-4) microM) approximately 15,000 times below its cytotoxic concentration. OBGS was also active postinfection (EC(50)=5.3 x 10(-4) microM) and protected pretreated peripheral mononuclear cells (EC(50)=5.2 x 10(-2) microM) washed free of the compounds prior to infection. Thus, OBGS has potential as a vaginal microbicide and is the first such report for oat bran derived sulfated beta-glucan.

Pharmacokinetics and bioavailability of gentiopicroside from decoctions of Gentianae and Longdan Xiegan Tang after oral administration in rats--comparison with gentiopicroside alone.

The pharmacokinetics and bioavailability of gentiopicroside (GPS), an active component of the Gentian plant species, from orally administered decoctions of Gentianae (DG), or in combination with other plants in the prescription of Longdan Xiegan Tang (LXT), was compared in rats with oral administration of GPS alone, using doses adjusted to deliver equivalent amounts of GPS (150 mg/kg). Changes in plasma levels of GPS following oral administration of GPS or DG could be fitted to a one compartment open model with elimination half times (T(1/2)Ke) of 3.35+/-0.76 h and 6.21+/-3.07 h, respectively. Kinetics of plasma GPS following oral administration of LXT could be fitted to a two compartments open model with an elimination half time (T((1/2)beta)) of 3.83+/-1.54 h. The bioavailability of GPS from DG was markedly better, and that from LXT markedly worse, compared with GPS alone, as judged by the area under concentration-time curve (AUC) values of 70.0+/-13.9 microgh/ml (DG), 32.7+/-12.9 microgh/ml (GPS) and 19.1+/-5.9 microgh/ml (LXT). The study demonstrates the marked variability in pharmacokinetics and bioavailability of an active component from different herbal preparations.

Pharmacokinetic behavior of gentiopicroside from decoction of Radix Gentianae, Gentiana macrophylla after oral administration in rats: a pharmacokinetic comaprison with gentiopicroside after oral and intravenous administration alone.

The pharmacokinetics in rats of gentiopicroside (GPS) from orally administered decoctions of Radix Gentianae (DRG) and Gentiana macrophlla (DGM) were compared with that of GPS alone administered at 150 mg/kg orally and 30 mg/kg intravenously. The metabolic profile of GPS after intravenous injection could be fitted to two-compartment model whereas oral administration decoctions DRG or DGM, or GPS alone, could all be fitted to a one-compartment model. After oral administration of GPS alone, GPS was absorbed quickly and reached a maximum plasma concentration (Cmax) value, 5.78 +/- 2.24 microg/mL within 0.75 +/- 0.62 h. The plasma level of GPS declined with a T1/2ke, 3.35 +/- 0.76 h. After oral administration of decoctions DRG and DGM, GPS was absorbed and reached significantly higher maximum concentrations of 10.53 +/- 3.20 microg/mL (p < 0.01) and 7.43 +/- 1.64 microg/mL (p < 0.05) at later time points 1.60 +/- 0.76 (p < 0.01) and 2.08 +/- 0.74 h (p < 0.05), for DRG and DGM respectively, compared with oral GPS alone. Significantly larger AUC values were found for decoctions of GPS (83.49 +/- 20.8 microgxh/mL for DRG and 59.43 +/- 12.9 microgxh/mL for DGM) compared with oral GPS alone (32.67 +/- 12.9 microgxh/mL). The results demonstrate that the bioavailability of GPS was markedly improved when administered as a decoction than as purified GPS. The decoction from Radix Gentianae provided 2.5 times better bioavailability and that from Gentiana macrophlla 1.8 times higher. The study confirms the importance of careful pharmacokinetic analysis in the characterization of herbal medicines when applied for future clinical applications.

Core-Sheath Nanofibers as Drug Delivery System for Thermoresponsive Controlled Release.

In this work, a smart drug delivery system of core-sheath nanofiber is reported. The core-sheath nanofibers were prepared with thermoresponsive poly-(N-isopropylacrylamide) (as core) and hydrophobic ethyl cellulose (as sheath) by coaxial electrospinning. Analogous medicated fibers were prepared by loading with a model drug ketoprofen (KET). The fibers were cylindrical without phase separation and have visible core-sheath structure as shown by scanning and transmission electron microscopy. X-ray diffraction patterns demonstrated the drug with the amorphous physical form was present in the fiber matrix. Fourier transform infrared spectroscopy analysis was conducted, finding that there were significant intermolecular interactions between KET and the polymers. Water contact angle measurements proved that the core-sheath fibers from hydrophilic transformed into hydrophobic when the temperature reached the lower critical solution temperature. In vitro drug-release study of nanofibers with KET displayed that the coaxial nanofibers were able to synergistically combine the characteristics of the 2 polymers producing a temperature-sensitive drug delivery system with sustained-release properties. In addition, they were established to be nontoxic and suitable for cell growth. These findings show that the core-sheath nanofiber is a potential candidate for controlling drug delivery system.