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Molecular Pharmaceutics Nov 2019The preparative resolution by preferential crystallization (PC) of proxyphylline has been achieved despite the existence of a stable racemic compound. This is enabled...
The preparative resolution by preferential crystallization (PC) of proxyphylline has been achieved despite the existence of a stable racemic compound. This is enabled through the careful selection of a solvent in which both the racemic compound and the metastable conglomerate possess a low nucleation rate. Induction time measurements in isobutyl alcohol show that a highly supersaturated solution (β = 2.3) remains clear for almost 1 h at 20 mL scale, revealing a slow nucleation rate. Seeding the supersaturated solution with the pure enantiomer triggered its crystallization both isothermal and polythermic modes of PC were successfully implemented. Alongside the reported case of diprophylline, this study opens opportunities to broaden the application of PC toward slowly crystallizing racemic compounds.
Topics: Butanols; Crystallization; Crystallography, X-Ray; Dyphylline; Solubility; Solutions; Solvents; Stereoisomerism; Theophylline; X-Ray Diffraction
PubMed: 31545612
DOI: 10.1021/acs.molpharmaceut.9b00805 -
AAPS PharmSciTech Apr 2019The aims of this study were to prepare hydrogenated soybean phosphatidylcholine (HSPC) matrices by hot melt extrusion and to evaluate resulting matrix potential to...
The aims of this study were to prepare hydrogenated soybean phosphatidylcholine (HSPC) matrices by hot melt extrusion and to evaluate resulting matrix potential to extend drug release in regard to drug loading and solubility for oral drug delivery of water-soluble drugs. The liquid crystalline nature of HSPC powder allowed its extrusion at 120°C, which was below its capillary melting point. Model drugs with a wide range of water solubilities (8, 20 and 240 mg/mL) and melting temperatures (160-270°C) were used. Extrudates with up to 70% drug loading were prepared at temperatures below the drugs' melting points. The original crystalline state of the drugs remained unchanged through the process as confirmed by XRPD and hot-stage microscopy. The time to achieve 80% release (t) from extrudates with 50% drug loading was 3, 8 and 18 h for diprophylline, caffeine and theophylline, respectively. The effect of matrix preparation method (extrusion vs. compression) on drug release was evaluated. For non-eroding formulations, the drug release retarding properties of the HSPC matrix were mostly not influenced by the preparation method. However, with increasing drug loadings, compressed tablets eroded significantly more than extruded matrices, resulting in 2 to 11 times faster drug release. There were no signs of erosion observed in extrudates with different drugs up to 70% loadings. The mechanical robustness of HSPC extrudates was attributed to the formation of a skin-core structure and was identified as the main reason for the drug release controlling potential of the HSPC matrices produced by hot melt extrusion.
Topics: Administration, Oral; Delayed-Action Preparations; Drug Delivery Systems; Excipients; Hot Temperature; Hydrogenation; Phosphatidylcholines; Solubility; Glycine max; Technology, Pharmaceutical; Theophylline
PubMed: 30968304
DOI: 10.1208/s12249-019-1366-3 -
Oncology Letters Jan 2019Diprophylline (DPL) is identified as a methylxanthine (MX) derivative. A number of MX derivatives are reported to have anti-tumor effects. However, it is not clear...
Diprophylline (DPL) is identified as a methylxanthine (MX) derivative. A number of MX derivatives are reported to have anti-tumor effects. However, it is not clear whether DPL has a therapeutic effect on non-small cell lung cancer (NSCLC). The aim of the present study was to investigate the effects of DPL on NSCLC and to elucidate the potential underlying mechanism. A Cell Counting Kit-8 assay was used to evaluate the potential effect of DPL on A549 cell proliferation. Transwell invasion and migration assays were performed to assess the effect of DPL on A549 cell migration and invasion. Furthermore, the percentage of apoptotic cells was detected by flow cytometric analysis, and proteins associated with apoptosis, including apoptosis regulator Bcl-2, apoptosis regulator BAX and active caspase-3, were examined by western blotting. Finally, the expression levels of molecules relevant to phosphoinositide 3-kinase (PI3K) signaling were detected by western blot analysis. The present study demonstrated that DPL may significantly inhibit A549 cell proliferation, migration and invasion. Furthermore, treatment with DPL may significantly induce A549 cell apoptosis. Finally, the protein expression levels associated with the PI3K signaling pathway were significantly inhibited in A549 cells following treatment with DPL. In conclusion, DPL may inhibit the proliferation and migration of NSCLC by inactivating the PI3K signaling pathway, and DPL is a promising novel therapeutic drug for NSCLC.
PubMed: 30655839
DOI: 10.3892/ol.2018.9678 -
Open Access Macedonian Journal of... May 2018Blocking effect of leukotriene biosynthesis-zileuton and blocking the effect of phosphodiesterase enzyme-diprophylline in the treatment of patients with bronchial asthma...
AIM
Blocking effect of leukotriene biosynthesis-zileuton and blocking the effect of phosphodiesterase enzyme-diprophylline in the treatment of patients with bronchial asthma and bronchial increased reactivity, and tiotropium bromide as an antagonist of the muscarinic receptor studied in this work.
METHODS
Parameters of the lung function are determined with Body plethysmography. The resistance of the airways (Raw) was registered and measured was intrathoracic gas volume (ITGV), and specific resistance (SRaw) was also calculated. For the research, administered was zileuton (tabl. 600 mg) and diprophylline (tabl. 150 mg).
RESULTS
Two days after in-house administration of leukotriene biosynthesis blocker-zileuton (4 x 600 mg orally), on the day 3 initial values of patients measured and afterwards administered 1 tablet of zileuton, and again measured was Raw and ITGV, after 60, 90 and 120 min. and calculated was SRaw; (p < 0.01). Diprophylline administered 7 days at home in a dose of (2 x 150 mg orally), on the day 8 to same patients administered 1 tablet of diprophylline, and performed measurements of Raw, ITGV, after 60, 90 and 120 min, and calculated the SRaw (p < 0.05). Treatment of the control group with tiotropium bromide - antagonist of the muscarinic receptor (2 inh. x 0.18 mcg), is effective in removal of the increased bronchomotor tonus, by also causing the significant decrease of the resistance (Raw), respectively of the specific resistance (SRaw), (p < 0.05).
CONCLUSION
Effect of zileuton in blocking of leukotriene biosynthesis is not immediate after oral administration, but the effect seen on the third day of cys-LTs' inhibition, and leukotriene B4 (LTB4) and A4 (LTA4) in patients with bronchial reactivity and bronchial asthma, which is expressed with a high significance, (p < 0.01). Blockage of phosphodiesterase enzyme-diprophylline decreases the bronchial reactivity, which is expressed with a moderate significance, (p < 0.05).
PubMed: 29875845
DOI: 10.3889/oamjms.2018.187 -
Chemical & Pharmaceutical Bulletin 2018A mixture of pharmaceuticals having a xanthine skeleton, theophylline, proxyphylline, diprophylline and (-)-epigallocatechin-3-O-gallate (EGCg) in water created a sticky...
A mixture of pharmaceuticals having a xanthine skeleton, theophylline, proxyphylline, diprophylline and (-)-epigallocatechin-3-O-gallate (EGCg) in water created a sticky precipitates, which were thought to be 2 : 2 complexes of the pharmaceuticals and EGCg. The molecular capture ability of the pharmaceuticals having a xanthine skeleton by EGCg was estimated by the amount of the pharmaceuticals included in the precipitates of the complexes, and measured by the integrated value of proton signals in the quantitative H-NMR spectra. Based on changes in chemical shifts of proton signals of the pharmaceuticals with a xanthine skeleton in H-NMR spectra by adding standard amounts of EGCg, the xanthine skeleton of the pharmaceuticals was considered to exist in the hydrophobic space formed by the three aromatic A, B, B' rings of EGCg, and a part of the proxyphylline and diprophylline side chains existed out of the hydrophobic space. In the H-NMR spectra of the mixture of (R)- and (S)-proxyphylline, (R)- and (S)-diprophylline and an equimolecular amount of EGCg, the N-CH signal of (R)- and (S)-proxyphylline, and (R)- and (S)-diprophylline was clearly observed as two singlets. This suggested that EGCg recognized the chirality of proxyphylline and diprophylline in water.
Topics: Catechin; Molecular Structure; Pharmaceutical Preparations; Stereoisomerism; Water; Xanthine
PubMed: 29863063
DOI: 10.1248/cpb.c18-00027 -
Journal of Cellular Physiology Jun 2018Osteoporosis is a common skeletal disorder characterized by low bone mass leading to increased bone fragility and fracture susceptibility. Identification of factors... (Comparative Study)
Comparative Study
Osteoporosis is a common skeletal disorder characterized by low bone mass leading to increased bone fragility and fracture susceptibility. Identification of factors influencing osteoblast differentiation and bone formation is very important. Previously, we identified parbendazole to be a novel compound that stimulates osteogenic differentiation of human mesenchymal stromal cells (hMSCs), using gene expression profiling and bioinformatic analyzes, including the Connectivity Map (CMap), as an in-silico approach. The aim for this paper is to identify additional compounds affecting osteoblast differentiation using the CMap. Gene expression profiling was performed on hMSCs differentiated to osteoblasts using Illumina microarrays. Our osteoblast gene signature, the top regulated genes 6 hr after induction by dexamethasone, was uploaded into CMap (www.broadinstitute.org/cmap/). Through this approach we identified compounds with gene signatures positively correlating (withaferin-A, calcium folinate, amylocaine) or negatively correlating (salbutamol, metaraminol, diprophylline) to our osteoblast gene signature. All positively correlating compounds stimulated osteogenic differentiation, as indicated by increased mineralization compared to control treated cells. One of three negatively correlating compounds, salbutamol, inhibited dexamethasone-induced osteoblastic differentiation, while the other two had no effect. Based on gene expression data of withaferin-A and salbutamol, we identified HMOX1 and STC1 as being strongly differentially expressed . shRNA knockdown of HMOX1 or STC1 in hMSCs inhibited osteoblast differentiation. These results confirm that the CMap is a powerful approach to identify positively compounds that stimulate osteogenesis of hMSCs, and through this approach we can identify genes that play an important role in osteoblast differentiation and could be targets for novel bone anabolic therapies.
Topics: Bone Density; Bone Density Conservation Agents; Cell Differentiation; Computational Biology; Gene Expression Profiling; Gene Expression Regulation; Gene Regulatory Networks; Glycoproteins; Heme Oxygenase-1; Humans; Mesenchymal Stem Cells; Oligonucleotide Array Sequence Analysis; Osteoblasts; Osteogenesis; Protein Interaction Maps; Signal Transduction
PubMed: 29194609
DOI: 10.1002/jcp.26298 -
BMC Pharmacology & Toxicology Nov 2017Zebrafish embryos are emerging as a model for pharmacological and toxicological studies. We used zebrafish embryos to study the general toxicity and cardiovascular...
BACKGROUND
Zebrafish embryos are emerging as a model for pharmacological and toxicological studies. We used zebrafish embryos to study the general toxicity and cardiovascular effects of eight methylxanthines: aminophylline, caffeine, diprophylline, doxofylline, etophylline, 3-isobutyl-1-methylxanthine (IBMX), pentoxifylline and theophylline.
METHODS
Microinjections of the eight methylxanthines were performed in 1-2 cell stage zebrafish embryos and the general toxicity and cardiovascular effects were analyzed at different time points. Embryotoxicity and teratogenicity were evaluated to understand the general toxicity of these compounds. Structural and functional alterations of the heart were evaluated to assess the cardiovascular effects.
RESULTS
Our results showed different activity patterns of the methylxanthines drugs. Caffeine, IBMX, pentoxifylline and theophylline were highly embryotoxic and teratogenic; aminophylline, doxofylline and etophylline were embryotoxic and teratogenic only at higher doses, and diprophylline showed a minimal (<10%) embryotoxicity and teratogenicity. Most of these drugs induced structural alteration of the heart in 20-40% of the injected embryos with the maximum dose. This structural alteration was fatal with the embryos ultimately dying within 120 hpf. All the drugs induced a transient increase in heart rate at 48 hpf which returned to baseline within 96 hpf. This functional effect of methylxanthines showed similarity to the studies done in humans and other vertebrates.
CONCLUSION
Our results indicate the potential toxicity and teratogenicity of different methylxanthines in the embryos during embryonic development, the most sensitive period of life. Although interspecies differences need to be considered before drawing any conclusion, our study elucidated that a single exposure of methylxanthines at therapeutic range could induce cardiac dysfunction besides causing embryotoxicity and teratogenicity. Of all the drugs, diprophylline appeared to be safer, with lower degree of embryotoxicity, teratogenicity and cardiac toxicity as compared to other methylxanthines.
Topics: Animals; Embryo, Nonmammalian; Heart; Heart Rate; Xanthines; Zebrafish
PubMed: 29141695
DOI: 10.1186/s40360-017-0179-9 -
The Journal of Physical Chemistry. B Aug 2017A dielectric relaxation spectroscopy (DRS) study was performed to investigate the molecular mobility of amorphous chiral diprophylline (DPL). For this purpose, both...
A dielectric relaxation spectroscopy (DRS) study was performed to investigate the molecular mobility of amorphous chiral diprophylline (DPL). For this purpose, both racemic DPL and a single enantiomer of DPL were considered. After fast cooling from the melt at very low temperature (-140 °C), progressive heating below and above the glass transition (T ≈ 37 °C) induces two secondary relaxations (γ- and δ-) and primary relaxations (α-) for both enantiomeric compositions. After chemical purification of our samples by means of cooling recrystallization, no γ-process could be detected by DRS. Hence, it was highlighted that the molecular mobility in the glassy state is influenced by the presence of theophylline (TPH), the main impurity in DPL samples. We also proved that the dynamic behavior of a single enantiomer and the racemic mixture of the same purified compound are quasi-identical. This study demonstrates that the relative stability and the molecular mobility of chiral amorphous drugs are strongly sensitive to chemical purity.
Topics: Crystallization; Dielectric Spectroscopy; Pharmaceutical Preparations; Phase Transition; Stereoisomerism; Temperature; Theophylline
PubMed: 28726403
DOI: 10.1021/acs.jpcb.7b05667 -
European Journal of Pharmaceutical... Oct 2017The aim of this study was to evaluate the suitability of saturated phosphatidylcholine (Phospholipon® 90H) as extended release excipient in matrix tablets for three...
The aim of this study was to evaluate the suitability of saturated phosphatidylcholine (Phospholipon® 90H) as extended release excipient in matrix tablets for three model drugs with different aqueous solubility (theophylline, caffeine and diprophylline). The tablets could be prepared by direct compression because of the favorable phospholipid powder flow properties (Carr's index: 12.64 and angle of repose: 28.85) and good compactibility. Tablets of low porosity were formed already at low pressure of 40MPa and with drug loadings up to 70% due to high plasticity of the phospholipid. Extended drug release was achieved with the drugs of different solubility and at various drug loadings. For example, the caffeine release time (t) from 8mm tablets ranged from 1.5h to 18h at 70% and 10% drug loading, respectively. The drug release was governed by diffusion and could therefore be modelled by Fick's law of diffusion. Drug release profiles were thus a function of drug solubility, drug loading and tablet dimension. Matrix tablets of caffeine (20% drug loading) showed robust dissolution with regard to agitation (50-100rpm) and ionic strength of the release media (100-600 mOsmol/kg). Caffeine release was pH-dependent with a faster drug release at acidic pH, which was attributed to a protonization of the phosphatidyl group of the matrix-former and thus a higher hydrophilicity.
Topics: Administration, Oral; Caffeine; Chemistry, Pharmaceutical; Diffusion; Drug Delivery Systems; Drug Liberation; Excipients; Hydrophobic and Hydrophilic Interactions; Nanoparticles; Osmolar Concentration; Particle Size; Phosphatidylcholines; Porosity; Solubility; Tablets; Theophylline
PubMed: 28716757
DOI: 10.1016/j.ejps.2017.07.017