High blood pressure. Causes, symptoms, treatments

Mixture toxicity of the anti-inflammatory drugs diclofenac, ibuprofen, naproxen, and acetylsalicylic acid.

2017-04-29

Although ibuprofen [2-(4-isobutylphenyl)-propionic acid] is one of the most widely consumed drugs in the world, little is known regarding its degradation by environmental bacteria. Sphingomonas sp. strain Ibu-2 was isolated from a wastewater treatment plant based on its ability to use ibuprofen as a sole carbon and energy source. A slight preference toward the R enantiomer was observed, though both ibuprofen enantiomers were metabolized. A yellow color, indicative of meta-cleavage, accumulated transiently in the culture supernatant when Ibu-2 was grown on ibuprofen. When and only when 3-flurocatechol was used to poison the meta-cleavage system, isobutylcatechol was identified in the culture supernatant via gas chromatography-mass spectrometry analysis. Ibuprofen-induced washed-cell suspensions also metabolized phenylacetic acid and 2-phenylpropionic acid to catechol, while 3- and 4-tolylacetic acids and 2-(4-tolyl)-propionic acid were metabolized to the corresponding methyl catechols before ring cleavage. These data suggest that, in contrast to the widely distributed coenzyme A ligase, homogentisate, or homoprotocatechuate pathway for metabolism of phenylacetic acid and similar compounds, Ibu-2 removes the acidic side chain of ibuprofen and related compounds prior to ring cleavage.

Recent studies have shown potential for phenotypic-driven therapies for the management of preschool children with asthma. Targeting airway bacteria has emerged as a promising therapeutic approach, but its effect on antibiotic resistance still needs to be investigated. Finally, more studies are required to evaluate if oral corticosteroids provide any benefits for acute episodic wheeze.

The cancer chemopreventive properties and gastrointestinal toxicity of ibuprofen are well documented. Modification of existing NSAIDs has improved on the chemopreventive efficacy of this agent and reduced its toxicity. In this study, ibuprofen and a modified derivative (phospho-modified ibuprofen or p-ibuprofen) were used in a chemically induced model of colon cancer. Fisher 344 rats were injected with azoxymethane then treated with either ibuprofen (500 ppm) or p-ibuprofen (900 ppm) for 20 weeks to observe aberrant crypt foci (ACF) or 40 weeks to evaluate tumor incidence and multiplicity. β-catenin and p65 were measured in colonic tissues by immunofluorescence staining. Equal molar doses of ibuprofen (75 and 670 mg/kg) and p-ibuprofen (135 and 1,215 mg/kg) were administered to rats for 7 days to assess acute toxicity. The in vitro effect of p-ibuprofen on COX-2 and PGE(2) synthesis, β-catenin expression and NF-κB activity were examined in RAW 264.7 macrophage and HCT 116 colon cancer cells. At week 20, p-ibuprofen and ibuprofen significantly reduced the multiplicity of ACF compared with control (p<0.05); 31.2 and 37.9%, respectively. At week 40, p-ibuprofen and ibuprofen reduced the multiplicity of colon tumors compared with control (p<0.01) by 47.2 and 56.6%, respectively. Equal molar concentrations of ibuprofen (670 mg/kg) and p-ibuprofen (1,215 mg/kg) resulted in stomach ulceration in 85.7% (6 out of 7) and 14.3% (1 out of 7) of rats, respectively, with p<0.01. Immunofluoresence staining and western blot analysis demonstrated that both ibuprofen and p-ibuprofen suppressed β-catenin nuclear translocation in colon cancer cells. In addition, p-ibuprofen but not ibuprofen inhibited NF-κB activation in colon cancer cells. Collectively, these results suggest that p-ibuprofen is a potential effective novel drug for long-term use in colon cancer prevention.

A simple, sensitive, and rapid liquid chromatographic method was developed and validated using diode array detection for the determination of five commonly used antimalarial drugs in pharmaceutical formulations and in human plasma. Chromatographic separation of antimalarial drugs and internal standard (ibuprofen) was achieved on a C18 column with a mobile phase composed of 10 mM dipotassium orthophosphate at pH 3.0, methanol, and acetonitrile in a ratio of 20:38:42 v/v, at a flow rate of 1 mL/min. The analytes were monitored at 220 nm and separated in ˂10 min. The method was validated for linearity, accuracy, precision, limit of quantification, and robustness. Both intra- and interday precisions (in terms of %RSD) were lower than 3% and accuracy ranged from 98.1 to 104.5%. Extraction recoveries were ≥96% in plasma. The limits of quantitation for artemether, lumefantrine, pyrimethamine, sulfadoxine, and mefloquine were 0.3, 0.03, 0.06, 0.15, and 0.15 μg/mL in human plasma. Stability under various conditions was also investigated. The method was successfully applied for quantification of antimalarial drugs in marketed formulations and in spiked human plasma. The method can be employed for routine QC purposes and in pharmacokinetic investigations.

National Institute of Health and Clinical Excellence (NICE) guidance stated that a new form of non-steroidal anti-inflammatory drug (NSAID) (selective COX-2 inhibitors) should only be an option for arthritis patients at high risk of a gastro-intestinal (GI) event. Total expenditure on NSAIDs has risen by 57% over five years, to 247 pounds sterling million in 2004. We assess whether this expenditure increase can be accounted for by substitution--an increased prescribing of two (more expensive) selective COX-2 inhibitors (celecoxib and rofecoxib) and a simultaneous equivalent reduction in the prescribing volume of three (cheaper) older NSAIDs (diclofenac, ibuprofen and naproxen).