Activity Screening of Fatty Acid Mimetic Drugs Identified Nuclear Receptor Agonists.

Fatty acid mimetics (FAM) are bioactive molecules acting through the binding sites of endogenous fatty acid metabolites on enzymes, transporters, and receptors. Due to the special characteristics of these binding sites, FAMs share common chemical features. Pharmacological modulation of fatty acid signaling has therapeutic potential in multiple pathologies, and several FAMs have been developed as drugs. We aimed to elucidate the promiscuity of FAM drugs on lipid-activated transcription factors and tested 64 approved compounds for activation of RAR, PPARs, VDR, LXR, FXR, and RXR. The activity screening revealed nuclear receptor agonism of several FAM drugs and considerable promiscuity of NSAIDs, while other compound classes evolved as selective. These screening results were not anticipated by three well-established target prediction tools, suggesting that FAMs are underrepresented in bioactivity data for model development. The screening dataset may therefore valuably contribute to such tools. Oxaprozin (RXR), tianeptine (PPARδ), mycophenolic acid (RAR), and bortezomib (RAR) exhibited selective agonism on one nuclear receptor and emerged as attractive leads for the selective optimization of side activities. Additionally, their nuclear receptor agonism may contribute relevant and valuable polypharmacology.

Oxaprozin-Loaded Lipid Nanoparticles towards Overcoming NSAIDs Side-Effects.

PURPOSE: Nanostructured Lipid Carriers (NLCs) loading oxaprozin were developed to address an effective drug packaging and targeted delivery, improving the drug pharmacokinetics and pharmacodynamics properties and avoiding the local gastric side-effects. Macrophages actively phagocyte particles with sizes larger than 200 nm and, when activated, over-express folate beta receptors - features that in the case of this work constitute the basis for passive and active targeting strategies. METHODS: Two formulations containing oxaprozin were developed: NLCs with and without folate functionalization. In order to target the macrophages folate receptors, a DSPE-PEG2000-FA conjugate was synthesized and added to the NLCs. RESULTS: These formulations presented a relatively low polydispersity index (approximately 0.2) with mean diameters greater than 200 nm and zeta potential inferior to -40 mV. The encapsulation efficiency of the particles was superior to 95% and the loading capacity was of 9%, approximately. The formulations retained the oxaprozin release in simulated gastric fluid (only around 10%) promoting its release on simulated intestinal fluid. MTT and LDH assays revealed that the formulations only presented cytotoxicity in Caco-2 cells for oxaprozin concentrations superior to 100 µM. Permeability studies in Caco-2 cells shown that oxaprozin encapsulation did not interfered with oxaprozin permeability (around 0.8 × 10(-5) cm/s in simulated intestinal fluid and about 1.45 × 10(-5) cm/s in PBS). Moreover, in RAW 264.7 cells NLCs functionalization promoted an increased uptake over time mainly mediated by a caveolae uptake mechanism. CONCLUSIONS: The developed nanoparticles enclose a great potential for oxaprozin oral administration with significant less gastric side-effects.

Synthesis of extended oxazoles II: Reaction manifold of 2-(halomethyl)-4,5-diaryloxazoles.

2-(Halomethyl)-4,5-diphenyloxazoles are effective, reactive scaffolds which can be utilized for synthetic elaboration at the 2-position. Through substitution reactions, the chloromethyl analogue is used to prepare a number of 2-alkylamino-, 2-alkylthio- and 2-alkoxy-(methyl) oxazoles. The 2-bromomethyl analogue offers a more reactive alternative to the chloromethyl compounds and is useful in the C-alkylation of a stabilized (malonate) carbanion as exemplified by a concise synthesis of Oxaprozin.

Transition metal(II) complexes with the non-steroidal anti-inflammatory drug oxaprozin: Characterization and biological profile.

A series of copper(II), nickel(II) and cobalt(II) complexes with the non-steroidal anti-inflammatory drug oxaprozin (Hoxa) have been synthesized and characterized by diverse techniques. The crystal structures of two copper(II) complexes, namely the dinuclear complex [Cu2(oxa)4(DMF)2] (1) and the polymeric complex {[Cu2(oxa)4]·2MeOH·0.5MeOH}2 (12) were determined by single-crystal X-ray diffraction studies. In order to evaluate in vitro the antioxidant activity of the resultant complexes, their scavenging ability towards 1,1-diphenyl-picrylhydrazyl (DPPH), hydroxyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals was investigated revealing their high effectiveness against these radicals. The binding of the complexes to bovine serum albumin and human serum albumin was examined and the corresponding determined albumin-binding constants showed a tight and reversible interaction. The interaction of the complexes with calf-thymus DNA was monitored by diverse techniques including UV-vis spectroscopy, cyclic voltammetry, DNA-viscosity measurements and competitive studies with ethidium bromide. Intercalation may be proposed as the most possible DNA-interaction mode of the complexes.

Nonsteroidal Anti-inflammatory Drug Oxaprozin is Beneficial Against Seizure-induced Memory Impairment in an Experimental Model of Seizures in Rats: Impact On Oxidative Stress and Nrf2/HO-1 Signaling Pathway.

There is substantial evidence that anti-inflammatory agents and antioxidants have neuroprotective properties and may be useful in the treatment of neurodegenerative disorders. In this regard, the effects of oxaprozin (OXP) (a nonsteroidal anti-inflammatory drug) on the experimental model of seizure and memory impairment caused by seizures in rats were investigated in the present study. Seizures in male Wistar rats (200-250 g, 8 weeks) were induced by pentylenetetrazol (PTZ, 60 mg/kg). The anticonvulsant effects of OXP (100, 200, and 400 mg/kg, administered intraperitoneally) were evaluated in the seizure model. The effect on memory was assessed using the passive avoidance (PA) test. After behavioral tests, the animals underwent deep anesthesia and were euthanized painlessly. Animal serum was isolated for antioxidant assays (MDA and GPx). The animals' brains (hippocampus) were also isolated to gauge the relative expression of genes in the oxidative stress pathway (Nrf2/HO-1). Intraperitoneal injection of OXP decreased the mean score on the Racine scale compared to the PTZ group. Moreover, in the PA test, OXP caused a significant increase in retention latency (RL) and total time spent in the light compartment (TLC) compared to the PTZ group. Biochemical tests showed that OXP was able to significantly increase GPx serum levels and significantly reduce MDA serum levels compared to the PTZ group. Quantitative polymerase chain reaction (qPCR) results also revealed that OXP counteracted the negative effects of PTZ by significantly increasing the expression of the Nrf2 and Hmox1 genes. Overall, this study suggests the potential neuroprotective effects of the nonsteroidal anti-inflammatory drug OXP in a model of memory impairment caused by seizures via inhibition of the oxidative stress pathway.

Development and In vitro and In vivo Evaluations of a Microemulsion Formulation for the Oral Delivery of Oxaprozin.

BACKGROUND: Oxaprozin is labeled as a Class II drug in the biopharmaceutical classification system, and its poor solubility in the entire gastrointestinal tract may be the main reason for its insufficient oral absorption capacity. OBJECTIVE: The purpose of this study was to develop an oxaprozin formulation to enhance its oral absorption. METHODS: Oxaprozin-loaded microemulsions were prepared using the titration method and pseudoternary phase diagram. Characterization experiments were performed on microemulsion preparations, including pH, particle size, shape, zeta potential, and stability (thermodynamic, dilution, and differential scanning calorimetry). Then, the in vitro release of the microemulsion and in vivo pharmacokinetics in rats were evaluated. RESULTS: Several microemulsion formulations were prepared. The optimal formulation was 15% oleoyl macrogolglycerides, 35% Tween 20/isopropanol (Km=2), and 50% distilled water. Its particle size met the requirements, and it had a spherical shape with a negatively charged surface. This microemulsion-loaded drug was applied to in vitro release and in vivo pharmacokinetic experiments at 7.47 mg/mL. In vitro release of the oxaprozin-loaded microemulsion best fit the firstorder model, while the microemulsion preparation had a certain sustained-release effect. In vivo pharmacokinetic experiments indicated that the microemulsion formulation significantly delayed the peak time of the blood concentration and simultaneously prolonged the half-life of drug elimination. CONCLUSION: The obtained data revealed satisfactory results for this novel microemulsion of oxaprozin, which is very meaningful for clinical trials.

The study of ultrasound and iontophoresis on oxaprozin transdermal penetration using surface-enhanced Raman spectroscopy.

The potential for physicochemical driving forces facilitating topical transport of the lipid-soluble drug oxaprozin (OXA) was investigated using surface-enhanced Raman spectroscopy (SERS) in this study. Azone, iontophoresis (IP), and sonophoresis (SP) were combined and performed on mouse skin for the OXA transdermal penetration, and the synergistic effect was analyzed using Raman spectroscopy. The data of characteristic peak intensity were processed with overlapping peak resolving and standard normalization. The results showed that Azone promoted the transdermal penetration of OXA (5.9-fold greater than the OXA concentration of normal penetration); SP enhanced OXA transdermal penetration (5.5-fold); IP enhanced OXA transdermal penetration (4.2-fold); the combined application of Azone and SP (Azone+SP) and SP+IP can improve the enhancement coefficient of OXA transdermal penetration (8.4-fold and 6.1-fold, > 5.9, > 5.5, > 4.2), and their combined application has a synergistic effect; Azone+IP does not have a synergistic effect while the enhancement coefficient of Azone+IP (5.3-fold, < 5.9) and Azone+SP+IP (7.2-fold, < 8.4) was slightly reduced. As for the drug OXA, Azone+SP is an effective method of transdermal penetration.

Zinc-oxaprozin compounds: Synthesis, structure and biological activity.

Four novel zinc complexes, namely [Zn(oxa)2(MeOH)4] (1), [Zn(oxa)2(H2O)(bipy)]·MeOH·2.5H2O (2·MeOH·2.5H2O), [Zn(oxa)2(bipyam)]·1.25MeOH (3·1.25MeOH) and [Zn(oxa)2(phen)] (4), with the non-steroidal anti-inflammatory drug oxaprozin (Hoxa) and a N,N'-donor heterocyclic ligand, such as 2,2'­bipyridylamine (bipyam), 1,10­phenanthroline (phen) or 2,2'­bipyridine (bipy), were characterized with physicochemical techniques, various spectroscopies and single-crystal X-ray crystallography. In these coordination compounds, the oxaprozin ligands are coordinated to zinc ion in a monodentate or a bidentate chelating binding mode. The antioxidant activity of the complexes was evaluated via their ability to scavenge in vitro 1,1­diphenyl­2­picrylhydrazyl, hydroxyl and 2,2'­azinobis­(3­ethylbenzothiazoline­6­sulfonic acid) radicals. The complexes bind to calf-thymus DNA via intercalation as suggested via a series of studies employing UV-vis spectroscopy, DNA-viscosity measurements and competition with ethidium bromide. The complexes may bind to serum albumins tightly and reversibly in order to get transferred through the bloodstream.

Oxaprozin: A new hope in the modulation of matrix metalloproteinase 9 activity.

Oxaprozin (4,5-diphenyl-2-oxazolepropionic acid) is a non-steroidal, analgesic and antipyretic propionic acid derivative, whose activity in treating inflammatory disorders is well known. The aim of this study was to investigate the ability of oxaprozin to modulate the activity of matrix metalloproteinase 9 (MMP-9), a zinc-dependent endopeptidase involved in a wide range of physiological and pathological events associated with extracellular matrix (ECM) remodelling. The interaction between oxaprozin and MMP-9 was firstly investigated in silico by molecular docking and analysis with LIGPLOT software. Subsequently, the potential inhibitory activity of oxaprozin against MMP-9 and the possible mechanism of the ligand-enzyme interaction were investigated in vitro. Taking into account the in silico findings, MMP-9 can be considered a potential target of oxaprozin, which seems to be able to chelate the catalytic zinc ion through the nitrogen of the oxazole ring and the carboxylate moiety. Moreover, one of the phenyl rings interact with the S1' inhibitor-binding pocket through hydrophobic interaction. Gelatin zymography and enzymatic inhibition assay confirmed the potential role of oxaprozin as a competitive inhibitor of MMP-9. These observations sound particularly interesting if we consider the pathological role of MMP-9, especially evident in inflammatory conditions and cancer. This work may represent a starting point to improve the understanding of the role of oxaprozin, as well as its structural analogues, in modulating the MMP-9 function.

Development and characterization of fast dissolving tablets of oxaprozin based on hybrid systems of the drug with cyclodextrins and nanoclays.

Previous studies highlighted an increase of the randomly-methylated-ß-cyclodextrin (RAMEB) solubilizing power towards oxaprozin when used in combination with L-arginine (ARG) or sepiolite nanoclay (SV). Therefore, the aim of this work was to investigate the possibility of maximising the RAMEB solubilizing efficacy by a joined approach based on the entrapment in SV of the drug-RAMEB-ARG complex. The quaternary nanocomposite was prepared by different techniques and characterized for solid state and dissolution properties, compared to ternary drug combinations with RAMEB-ARG, RAMEB-SV or ARG-SV. The dissolution rank order was drug-RAMEB-ARG-SV>>drug-RAMEB-ARG≈drug-RAMEB-SV>>drug-ARG-SV. The new hybrid nanocomposite enabled an increase from 60 up to 90% of oxaprozin dissolution parameters compared to the ternary systems with RAMEB-ARG and RAMEB-SV. Moreover, the lowest solubilizing efficacy of ternary systems with ARG-SV evidenced the specific synergic effect of both ARG and SV with RAMEB in enhancing oxaprozin dissolution properties. The superior performance of the quaternary nanocomposite was maintained after incorporation in a tablet formulation. In vivo studies on rats proved that the developed fast-dissolving tablet formulation, containing oxaprozin as cofused system with RAMEB, ARG and SV was more effective than the marketed tablet in terms of faster and more intense pain relieving effect in the treatment of adjuvant-induced arthritis.

Hybrid systems based on "drug - in cyclodextrin - in nanoclays" for improving oxaprozin dissolution properties.

A combined approach based on drug complexation with cyclodextrins, and complex entrapment in nanoclays has been investigated, to join in a single delivery system the benefits of these carriers and potentiate their ability to improve the dissolution properties of oxaprozin (OXA), a poorly water-soluble anti-inflammatory drug. Based on previous studies, randomly methylated ß-cyclodextrin (RAMEB) was chosen as the most effective cyclodextrin for OXA complexation. Adsorption equilibrium studies performed on three different clays (sepiolite, attapulgite, bentonite) allowed selection of sepiolite (SV) for its greater adsorption power towards OXA. DSC and XRPD studies indicated drug amorphization in both binary OXA-RAMEB coground and OXA-SV cofused products, due to its complexation or very fine dispersion in the clay structure, respectively. The drug amorphous state was maintained also in the ternary OXA-RAMEB-SV cofused system. Dissolution studies evidenced a clear synergistic effect of RAMEB complexation and clay nanoencapsulation in improving the OXA dissolution properties, with an almost 100% increase in percent dissolved and dissolution efficiency compared to the OXA-RAMEB coground system. Therefore, the proposed combined approach represents an interesting tool for improving the therapeutic effectiveness of poorly soluble drugs, and reducing the CD amount necessary for obtaining the desired drug solubility and dissolution rate increase.

Analysis of physicochemical properties of ternary systems of oxaprozin with randomly methylated-ß-cyclodextrin and l-arginine aimed to improve the drug solubility.

The influence of l-arginine on the complexing and solubilizing power of randomly-methylated-ß-cyclodextrin (RameßCD) towards oxaprozin, a very poorly soluble anti-inflammatory drug, was examined. The interactions between the components were investigated both in solution, by phase-solubility analysis, and in the solid state, by differential scanning calorimetry, FTIR and X-ray powder diffractometry. The morphology of the solid products was examined by Scanning Electron Microscopy. Results of phase-solubility studies indicated that addition of arginine enhanced the RameßCD complexing and solubilizing power of about 3.0 and 4.5 times, respectively, in comparison with the binary complex (both at pH≈6.8). The effect of arginine was not simply additive, but synergistic, being the ternary system solubility higher than the sum of those of the respective drug-CD and drug-arginine binary systems. Solid equimolar ternary systems were prepared by physical mixing, co-grinding, coevaporation and kneading techniques, to explore the effect of the preparation method on the physicochemical properties of the final products. The ternary co-ground product exhibited a dramatic increase in both drug dissolution efficiency and percent dissolved at 60min, whose values (83.6 and 97.1, respectively) were about 3 times higher than the sum of those given by the respective drug-CD and drug-aminoacid binary systems. Therefore, the ternary co-ground system with arginine and RameßCD appears as a very valuable product for the development of new more effective delivery systems of oxaprozin, with improved safety and bioavailability.

Comparison of liposomal and NLC (nanostructured lipid carrier) formulations for improving the transdermal delivery of oxaprozin: Effect of cyclodextrin complexation.

The combined strategy of drug-cyclodextrin (CD) complexation and complex loading into nanocarriers (deformable liposomes or nanostructured lipid carriers (NLC)), was exploited to develop effective topical formulations for oxaprozin transdermal administration. Oxaprozin was loaded as ternary complex with randomly-methylated-ßCD and arginine, selected as the best system in improving drug solubility. The colloidal dispersions, characterized for particle size, zeta-potential and entrapment efficiency, were investigated for drug permeation properties in comparison with a plain drug aqueous suspension, a ternary complex aqueous solution and a plain drug liposomal or NLC dispersion. Experiments with artificial membranes showed that the joined use of CD and both liposomes or NLC enabled a marked increase of the drug permeability (16 and 8 times, respectively) and was significantly more effective (P<0.05) than the drug as ternary complex (3.2 times increase), and the corresponding liposomal or NLC dispersion of plain drug (5.6 and 4.3 times increase, respectively). Experiments with excised human skin confirmed the significantly (P<0.05) better performance of deformable liposomes than NLC in promoting drug permeation; moreover, they evidenced a more marked permeability increase compared to the plain drug (24 and 12 fold, respectively), attributed to a possible enhancer effect of the nanocarriers components and/or of the randomly-methylated-ßCD.

Relative Bioavailability of 2 Kinds of Oxaprozin Enteric Tablets / 中国药房

OBJECTIVE:To compare the relative bioavailability of 2 kinds of domestic oxaprozin enteric tablets.METHODS:20 healthy volunteers were administered with single oral dose of trial tablet 400g and reference tablet 400g by crossover design,whose plasma oxaprozin level was determined by HPLC.The pharmacokinetic parameters and bioavailability of oxaprozin enterosoluble tablets were calculated by 3p97 software.RESULTS:The pharmacokinetic parameters of tested enteric tablets vs.reference tablets were as follows,t 1/2?(73.468?24.354),(73.556?24.406)h,t max(13.275?8.012),(13.200?15.154)h,C max(44.283?7.535)、(45.429?15.107)?g/ml,AUC 0～Tn(4471.792?1387.724),(4234.328?1741.380)(?g?h)/ml,AUC 0～inf(5040.407?2092.744),(4858.292?2423.656)(?g?h)/ml;No significant differences were noted between 2 tablets.The relative bioavailability of tested tablet was(112.8?38.5)%.CONCLUSION:2 kinds of oxaprozin enterosoluble tablets were bioequivalent.

Study on Base Material Optimization of Oxaprozin Gel / 中国药房

OBJECTIVE: To observe the effects of different types of carbomers on percutaneous permeability of oxaprozin gels in vitro and to opitmize the formulation of oxaprozin gel. METHODS: The permeability test in vitro was carried out by using Franz diffusion cell with rats' ex vivo skin as barrier. RESULTS: The ex vivo permeability of oxaprozin gel was the best when the carbomer 940 used as its base material with its ex vivo permeability coefficient at 22.77?g/ (cm2?h) . CONCLUSION : The optimized gel base material can act as bases for the production of oxaprozin gel.

The bioequivalence of oxaprozin enteric tablet in healthy volunteers measured with HPLC / 中国药理学通报

Aim An HPLC method was established for the study on pharmacokinetics and bioequivalence of oxaprozin enteric tablet in healthy volunteers.Methods The oxaprozin in plasma was determined using HPLC method following a single oral dose of 400 mg of oxaprozin given respectively to 18 healthy male volunteers in an open randomized crossover design.The pharmacokinetic parameters and relative bioavailability were calculated to evaluate the bioequivalence of 2 preparations.Results AUC_(0-240 h) of oxaprozin tested tablet and reference tablet were(2852.86?871.00)and (2992.84?854.02)?g?L~(-1)?h,C_(max) were(33.48?11.36)and (32.70?7.30)?g?L~(-1),T_(max) were(12.1?5.7)and(13.8?5.8)h,T_(1[]2ke) were(57.11?8.51)and(60.98?7.97)h,respectively.These main pharmacokinetic parameters obtained showed no statistically significant difference between the 2 products.Conclusion The method is simple and sensitive.Both preparations are bioequivalent.

Preparation of Chitosan-oxaprozin Sustained Release Tablets / 中国药房

OBJECTIVE: To study the preparation and quality standard of chitosan-oxaprozin sustained release tablets, and observe the rule of in vitro release of oxaprozin. METHODS:The content of oxaprozin in the tablets was determined by UV - spectrophotometry. RESULTS:The linear range was 2. 5- 15. 0ug/ml. The average recovery was 99. 79% with a RSD of 0. 38%. CONCLUSION: The preparation process of chitosan-oxaprozin sustained release tablet is simple. It is worth expanding the app- lication in clinical practice.