Toward Multitasking Pharmacological COX-Targeting Agents: Non-Steroidal Anti-Inflammatory Prodrugs with Antiproliferative Effects.

The antitumor activity of certain anti-inflammatory drugs is often attributed to an indirect effect based on the inhibition of COX enzymes. In the case of anti-inflammatory prodrugs, this property could be attributed to the parent molecules with mechanism other than COX inhibition, particularly through formulations capable of slowing down their metabolic conversion. In this work, a pilot docking study aimed at comparing the interaction of two prodrugs, nabumetone (NB) and its tricyclic analog 7-methoxy-2,3-dihydro-1H-cyclopenta[b]naphthalen-1-one (MC), and their common active metabolite 6-methoxy-2-naphthylacetic acid (MNA) with the COX binding site, was carried out. Cytotoxicity, cytofluorimetry, and protein expression assays on prodrugs were also performed to assess their potential as antiproliferative agents that could help hypothesize an effective use as anticancer therapeutics. Encouraging results suggest that the studied compounds could act not only as precursors of the anti-inflammatory metabolite, but also as direct antiproliferative agents.

Preparation, characterization and in vitro cytotoxicity of Fenofibrate and Nabumetone loaded solid lipid nanoparticles.

There is an increasing attention on solid lipid nanoparticles (SLNs) due to their high biocompatibility and ability to enhance bioavailability for poorly water-soluble drugs. Preparation of SLNs that are capable of high drug loading and sustained drug release through hot melt sonication method is reported here. SLNs of palmitic acid and stearic acid loaded with poorly water-soluble drugs, viz. fenofibrate (FF) and nabumetone (NBT) having spherical morphology and average particle size below 200 nm were prepared. Poloxamer 407 and pluronic® F-127 were used as surfactants. Particle size and spherical morphology was confirmed by dynamic light scattering, field emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. The chemical, crystal, and thermal properties of SLNs were studied by Fourier transform infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry, respectively. The palmitic acid-poloxamer 407 SLNs could entrap upto 13.8% FF with 80% entrapment efficiency while the stearic acid-pluronic® F-127 SLNs entrapped 13.6% NBT with 89% entrapment efficiency. The drug loaded in SLNs showed controlled release up to 3 days as confirmed by in-vitro drug release profile. Moreover, the drug loaded SLNs did not show any toxicity on macrophage cell line proving the use of these formulations as control drug delivery vehicles for the studied drugs.

Determination of the Absolute Configuration of the Nabumetone Metabolite 4-(6-Methoxy-2-naphthyl)butan-2-ol Using the Chiral Derivatizing Agent, 1-Fluoroindan-1-carboxylic Acid.

The absolute configuration of (+)-4-(6-methoxy-2-naphthyl)butan-2-ol ((+)-MNBO), a nabumetone metabolite, was determined using 1-fluoroindan-1-carboxylic acid (FICA). Both enantiomers of the FICA methyl esters were derivatized to diastereomeric esters of (+)-MNBO by an ester exchange reaction. The results of 1H- and 19F-NMR spectroscopy of the diastereomeric FICA esters of (+)-MNBO confirmed the absolute configuration of (+)-MNBO was (S).

Probing the Interplay between Amorphous Solid Dispersion Stability and Polymer Functionality.

Amorphous solid dispersions containing a polymeric component often impart improved stability against crystallization for a small molecule relative to the pure amorphous form. However, the relationship between side chain functionalities on a polymer and the ability of a polymer to stabilize against crystallization is not well understood. To shed light on this relationship, a series of polymers were functionalized from a parent batch of poly(chloromethylstyrene- co-styrene) to investigate the effect of functionality on the stability in amorphous solid dispersions without altering the physical parameters of polymers, such as the average molecular weight or backbone chain chemistry. The kinetics of the crystallization of the nonsteroidal anti-inflammatory drug nabumetone from amorphous solid dispersions containing each functionalized polymer were interpreted on the basis of two interactions: hydrogen bonding between the drug and the polymer and the solubility of the polymer in the amorphous drug. It was found that hydrogen bonding between functionalized polymers and nabumetone can impart stability against crystallization, but only if the polymer shows significant solubility in amorphous nabumetone. Methylation of a protic functionality can improve the ability of a polymer to inhibit nabumetone crystallization by increasing the solubility in the drug, even when the resulting polymer lacks hydrogen bonding functionalities to interact with the pharmaceutical. Furthermore, factors, such as the glass transition temperature of pure polymers, were uncorrelated with isothermal nucleation rates. These findings inform a framework relating polymer functionality and stability deconvoluted from the polymer chain length or backbone chemistry with the potential to aid in the design of polymers to inhibit the crystallization of hydrophobic drugs from amorphous solid dispersions.