Nitro-arginine methyl ester, a non-selective inhibitor of nitric oxide synthase reduces ibuprofen-induced gastric mucosal injury in the rat

Ibuprofen-Induced Renal Tubular Acidosis: Case Report on a Not-So-Basic Clinical Conundrum

Rationale

Renal tubular acidosis (RTA) is a cause of non-anion gap metabolic acidosis (NAGMA) that is infrequently diagnosed and is due to various underlying etiologies that impair the kidney's ability to retain bicarbonate or excrete acid. Ibuprofen is an over-the-counter non-steroidal anti-inflammatory medication that is used by patients widely for a variety of reasons. Although it is well known that ibuprofen and other non-steroidal anti-inflammatory drugs may have nephrotoxic effects, the role of ibuprofen as a cause of RTA and hypokalemia is not well recognized.

Presenting Concerns

A 66-year-old man with chemotherapy-treated lymphoma in remission and ongoing heavy ibuprofen use for chronic pain presented to hospital with a 1-week history of increasing lethargy and otherwise unremarkable review of systems. Investigations showed acute kidney injury, hypokalemia, hyperchloremia, and NAGMA with elevated urinary pH and positive urine anion gap.

Diagnoses

The final diagnosis of distal RTA secondary to ibuprofen was made after ruling out gastrointestinal bicarbonate loss and additional secondary causes of RTA, including other medications, autoimmune conditions, and obstructive uropathy.

Interventions

The patient was admitted and treated with intravenous sodium bicarbonate for 24 hours with correction of hypokalemia via oral supplementation. His ibuprofen-containing medication was discontinued.

Outcomes

His acute kidney injury and electrolyte abnormalities resolved within 48 hours of initiating treatment with concurrent resolution of his lethargy. He was discharged home and advised to stop taking ibuprofen.

Lessons Learned

We report a case of patient with hypokalemia and NAGMA secondary to ibuprofen and highlight the importance of monitoring for this side effect in patients taking ibuprofen.

ROS-responsive copolymer micelles for inflammation triggered delivery of ibuprofen

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used for the treatment of pain, inflammation and fever. However, most NSAIDs are poorly water soluble, making it difficult to be administered thus high doses are required to reach the intended therapeutic effect, resulting in associated side effects. In this study, ROS-responsive micellar systems based on a block copolymer consisting of methylpropyl thioether (MTPA) and N'N-dimethylacrylamide was developed and loaded with ibuprofen (IBU). Using lipopolysaccharide activated RAW 264.7 macrophage like cells, we demonstrated that IBU was released from the copolymer, specifically in the presence of ROS. Interestingly, IBU encapsulated in ROS-responsive nanoparticles exhibited greater anti-inflammatory potency compared to its free form. The work highlights the potential of the ROS-responsive micellar system developed in this work to be used as carrier of NSAIDs for the treatment of relevant inflammatory conditions.

Seasonal Occurrence of Ibuprofen in Sediment, Water, and Biota in River Owena and Ogbese, and its Ecological Risk Assessment

The volume of pharmaceuticals discharged into the environment increases daily as a consequence of human life. In the present study, the seasonal variation of ibuprofen in sediment, biota, water, and their exposure risk were investigated in River Owena and Ogbese, Nigeria. The high-performance liquid chromatography coupled to a mass spectrometer (HPLC-MS/MS) was used to analyze the samples after clean up and pre-concentration by solid-phase extraction. The mean concentration of IBU in the samples spanned a range of 1.75 - 2.75 μg/g in sediment, 0.01 – 15.00 μg/g in fish, and 0.00002 – 0.005 μg/ml in water. The measurement of IBU in the sediment and water was significantly elevated in the dry season than the wet season, whereas the opposite was the case in biota. There was a significant interaction between season, media, and rivers with respect to IBU occurrence in the sampled rivers. The calculated bio-water accumulation factor (BWAF) was as high as 750,000 μg/g in fish, proving IBU is extremely bio-accumulative. The ecotoxicological risk assessment for average and worst possible outcome showed that the risk quotient (RQ) for IBU present in the water was sufficient to cause toxicity to fish in both freshwater bodies. The potential bioavailability of IBU to aquatic fauna for prolonged periods spanning several months can result in its circling back into the food web afterward. The baseline info provided by this study in these freshwaters may provide valuable information for the implementation of safety limits for the management of IBU influx into the environment.

Soy Protein Microparticles for Enhanced Oral Ibuprofen Delivery: Preparation, Characterization, and In Vitro Release Evaluation

The objective of this work was to evaluate soy protein isolate (SPI) and acylated soy protein (SPA) as spray-drying encapsulation carriers for oral pharmaceutical applications. SPI acylation was performed by the Schotten-Baumann reaction. SPA, with an acylation rate of 41%, displayed a decrease in solubility in acidic conditions, whereas its solubility was unaffected by basic conditions. The drug encapsulation capacities of both SPI and SPA were tested with ibuprofen (IBU) as a model poorly soluble drug. IBU-SPI and IBU-SPA particles were obtained by spray-drying under eco-friendly conditions. Yields of 70 to 87% and microencapsulation efficiencies exceeding 80% were attained for an IBU content of 20 to 40% w/w, confirming the excellent microencapsulation properties of SPI and the suitability of the chemical modification. The in vitro release kinetics of IBU were studied in simulated gastrointestinal conditions (pH 1.2 and pH 6.8, 37°C). pH-sensitive release patterns were observed, with an optimized low rate of release in simulated gastric fluid for SPA formulations, and a rapid and complete release in simulated intestinal fluid for both formulations, due to the optimal pattern of pH-dependent solubility for SPA and the molecular dispersion of IBU in soy protein. These results demonstrate that SPI and SPA are relevant for the development of pH-sensitive drug delivery systems for the oral route.

Polyelectrolyte complex nanoparticles based on chitosan and methoxy poly(ethylene glycol) methacrylate-co-poly(methylacrylic acid) for oral delivery of ibuprofen

In this study, the copolymer of methoxy poly(ethylene glycol) methacrylate-co-poly(methylacrylic acid) [poly(mPEGMA-co-MAA)] was synthesized via radical polymerization. Based on this copolymer, novel chitosan-modified poly(mPEGMA-co-MAA) nanoparticles (CS/NPs) were developed to improve the bio-availability of ibuprofen (IBU). Fourier transform infrared spectroscopy (FTIR) and ¹H nuclear magnetic resonance (¹H NMR) spectra were used to confirm the synthesis of the copolymers. The morphology of CS/NPs was investigated with transmission electron microscopy (TEM). Thermogravimetric analysis (TGA) was used to reveal the thermodynamic properties of the CS/NPs. The cytotoxicity of CS/NPs was assessed by the cell viability of 293T cells. FTIR and ¹H NMR spectra confirmed the synthesis of the novel copolymer. TEM photographs showed that the CS/NPs had a core-shell structure. High cell viability indicated that the CS/NPs were nontoxic. The in vitro release profiles suggested that the CS/NPs released IBU in pH 7.4 buffer in a continuous manner. Furthermore, the IBU-CS/NPs showed a long antifebrile effect. Animal experiments showed that the IBU-CS/NPs had obvious antifebrile effects. Therefore, CS/NPs could reduce the dosing frequency of IBU, and improve its bio-availability.

Translational initiation regulated by ATM in dendritic cells development

Ataxia telangiectasia mutated (ATM) protein has been implicated in multiple pathways such as DNA repair, cell cycle checkpoint, cell growth, development, and stem cell renewal. In this study, we demonstrate evidence that ATM is involved in granulocyte macrophage colony-stimulating factor (GM-CSF)-induced dendritic cell (DC) development from bone marrow (BM) cells. Inactivation of ATM protein results in decreased BM proliferation, leading to reduced DC development and their activity for T cell activation. Expression of Jak2, STAT5, and mTOR is suppressed in both wild-type and ATM-null BM prior to GM-CSF stimulation. Activation of those proteins is delayed and prolonged hypophosphorylation of 4EBP1 is observed in ATM-null BM when treated with GM-CSF, although Erk and p38 are similarly expressed and activated in both wild-type and ATM-null BM cell types. Akt is also suppressed in wild-type BM, and transduction of constitutively active Akt or STAT5 in ATM-null BM restores DC development. Together, these results illustrate that ATM deficiency causes impaired initiation of protein translation in BM, leading to immature development of DC.

Role of chemoprophylaxis with either NSAIDs or statins in patients with Barrett's esophagus

The incidence of esophageal adenocarcinoma, a poor prognosis neoplasia, has risen dramatically in recent decades. Barrett's esophagus represents the best-known risk factor for esophageal adenocarcinoma development. Non-steroidal anti-inflammatory drugs through cyclooxygenase-2 inhibition and prostaglandin metabolism regulation could control cell proliferation, increase cell apoptosis and regulate the expression of growth and angiogenic factors. Statins can achieve equivalent effects through prenylation and subsequently control of cellular signaling cascades. At present, epidemiological studies are small and underpowered. Their data could not justify either medication as a chemo-preventive agent. Population based studies have shown a 43% reduction of the odds of developing an esophageal adenocarcinoma, leaving out or stating a 25% reduction in patients consuming non-aspirin nonsteroidal anti-inflammatory drugs and a 50% reduction in those patients consuming aspirin. They have also stated a 19% reduction of esophageal cancer incidence when statins have been used. Observational studies have shown that non-steroidal anti-inflammatory drugs could reduce the adenocarcinoma incidence in patients with Barrett's esophagus by 41%, while statins could reduce the risk by 43%. The cancer preventive effect has been enhanced in those patients taking a combination of non-steroidal anti-inflammatory drugs and statins (a 74% decrease). Observational data are equivocal concerning the efficacy of non-steroidal anti-inflammatory drug subclasses. Non-steroidal anti-inflammatory drugs clearly have substantial potential for toxicity, while statins are rather safe drugs. In conclusion, both non-steroidal anti-inflammatory drugs and statins are promising chemopreventive agents and deserve further exploration with interventional studies. In the meanwhile, their use is justified only in patients with cardiovascular disease.

Cubic phase nanoparticles for sustained release of ibuprofen: formulation, characterization, and enhanced bioavailability study

In order to improve the oral bioavailability of ibuprofen, ibuprofen-loaded cubic nanoparticles were prepared as a delivery system for aqueous formulations. The cubic inner structure was verified by cryogenic transmission electron microscopy. With an encapsulation efficiency greater than 85%, the ibuprofen-loaded cubic nanoparticles had a narrow size distribution around a mean size of 238 nm. Differential scanning calorimetry and X-ray diffraction determined that ibuprofen was in an amorphous and molecular form within the lipid matrix. The in vitro release of ibuprofen from cubic nanoparticles was greater than 80% at 24 hours, showing sustained characteristics. The pharmacokinetic study in beagle dogs showed improved absorption of ibuprofen from cubic nanoparticles compared to that of pure ibuprofen, with evidence of a longer half-life and a relative oral bioavailability of 222% (P < 0.05). The ibuprofen-loaded cubic nanoparticles provide a promising carrier candidate with an efficient drug delivery for therapeutic treatment.

An overview of clinical pharmacology of Ibuprofen

Ibuprofen was the first member of Propionic acid derivatives introduced in 1969. It is a popular domestic and over the counter analgesic and antipyretic for adults and children. Ibuprofen has been rated as the safest conventional NSAID by spontaneous adverse drug reaction reporting systems in the UK. This article summarizes the main pharmacological effects, therapeutical applications and adverse drug reactions, drug-drug interactions and food drug interactions of ibuprofen that have been reported especially during the last 10 years.