Nonsteroid drug selectivities for cyclo-oxygenase-1 rather than cyclo-oxygenase-2 are associated with human gastrointestinal toxicity: a full in vitro analysis

Inherited human group IVA cytosolic phospholipase A2 deficiency abolishes platelet, endothelial, and leucocyte eicosanoid generation

Eicosanoids are important vascular regulators, but the phospholipase A₂ (PLA₂) isoforms supporting their production within the cardiovascular system are not fully understood. To address this, we have studied platelets, endothelial cells, and leukocytes from 2 siblings with a homozygous loss-of-function mutation in group IVA cytosolic phospholipase A₂ (cPLA₂α). Chromatography/mass spectrometry was used to determine levels of a broad range of eicosanoids produced by isolated vascular cells, and in plasma and urine. Eicosanoid release data were paired with studies of cellular function. Absence of cPLA₂α almost abolished eicosanoid synthesis in platelets (e.g., thromboxane A₂, control 20.5 ± 1.4 ng/ml vs. patient 0.1 ng/ml) and leukocytes [e.g., prostaglandin E₂ (PGE₂), control 21.9 ± 7.4 ng/ml vs. patient 1.9 ng/ml], and this was associated with impaired platelet activation and enhanced inflammatory responses. cPLA₂α-deficient endothelial cells showed reduced, but not absent, formation of prostaglandin I₂ (prostacyclin; control 956 ± 422 pg/ml vs. patient 196 pg/ml) and were primed for inflammation. In the urine, prostaglandin metabolites were selectively influenced by cPLA₂α deficiency. For example, prostacyclin metabolites were strongly reduced (18.4% of control) in patients lacking cPLA₂α, whereas PGE₂ metabolites (77.8% of control) were similar to healthy volunteer levels. These studies constitute a definitive account, demonstrating the fundamental role of cPLA₂α to eicosanoid formation and cellular responses within the human circulation.—Kirkby, N. S., Reed, D. M., Edin, M. L., Rauzi, F., Mataragka, S., Vojnovic, I., Bishop-Bailey, D., Milne, G. L., Longhurst, H., Zeldin, D. C., Mitchell, J. A., Warner, T. D. Inherited human group IVA cytosolic phospholipase A₂ deficiency abolishes platelet, endothelial, and leucocyte eicosanoid generation.

Novel nanosized formulations of two diclofenac acid polymorphs to improve topical bioavailability

In this work, nanocrystal formulations, containing two different diclofenac acid crystal forms, were developed with the aim to improve dermal drug bioavailability. Nanosuspensions were obtaining using wet media milling technique and were characterized in terms of size distribution, morphology, zeta potential, differential scanning calorimetry and X-ray powder diffractometry. The ability of the nanocrystals to improve dermal drug bioavailability was investigated in vitro using Franz diffusion vertical cells and newborn pig skin, in comparison with diclofenac acid coarse suspensions and a commercial topical formulation containing diclofenac sodium. Nanocrystals exhibited a mean diameter ranging between 279 and 315 nm and a PI lower than 0.25, as shown by PCS measurements. The XRDP and DSC analysis clearly indicated that the preparation process did not modify the diclofenac polymorphic forms. In vitro transdermal delivery experiments showed an improved skin deposition and permeation of the nanocrystals compared to coarse suspensions and diclofenac sodium commercial topical formulation. These results highlight the fundamental role of the crystal size on drug solubility and, thus, on the ability of a poorly soluble drug to cross the skin and accumulate in the deeper skin layers.

Low-dose SoluMatrix diclofenac : a review of safety across two Phase III studies in patients with acute and osteoarthritis pain

INTRODUCTION

Similar to other NSAIDs, diclofenac is associated with serious dose-related cardiovascular, gastrointestinal, and renal adverse events. Low-dose SoluMatrix diclofenac , containing submicron particles of diclofenac, was developed to provide effective analgesia at lower drug doses compared with currently available NSAIDs.

AREAS COVERED

The efficacy and safety of low-dose SoluMatrix diclofenac was evaluated in two randomized, placebo-controlled Phase III studies: a study in patients with acute pain following bunionectomy surgery and a study in patients with osteoarthritis pain of the hip or knee. In this review article, we summarize safety data from these studies.

EXPERT OPINION

The safety results from the Phase III studies indicate that all dosing regimens of low-dose SoluMatrix diclofenac up to 12 weeks are generally well tolerated. Few serious gastrointestinal, cardiovascular, renal, or hepatic adverse events commonly associated with NSAID use were reported in these studies. Although not directly compared, the safety of SoluMatrix diclofenac was similar to findings for other diclofenac drug products. The potential for safe and effective management of acute and chronic pain at reduced NSAID doses is attractive; definitive characterization of SoluMatrix diclofenac safety requires confirmation by long-term studies.

Advances in NSAID development: evolution of diclofenac products using pharmaceutical technology

Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) of the phenylacetic acid class with anti-inflammatory, analgesic, and antipyretic properties. Contrary to the action of many traditional NSAIDs, diclofenac inhibits cyclooxygenase (COX)-2 enzyme with greater potency than it does COX-1. Similar to other NSAIDs, diclofenac is associated with serious dose-dependent gastrointestinal, cardiovascular, and renal adverse effects. Since its introduction in 1973, a number of different diclofenac-containing drug products have been developed with the goal of improving efficacy, tolerability, and patient convenience. Delayed- and extended-release forms of diclofenac sodium were initially developed with the goal of improving the safety profile of diclofenac and providing convenient, once-daily dosing for the treatment of patients with chronic pain. New drug products consisting of diclofenac potassium salt were associated with faster absorption and rapid onset of pain relief. These include diclofenac potassium immediate-release tablets, diclofenac potassium liquid-filled soft gel capsules, and diclofenac potassium powder for oral solution. The advent of topical formulations of diclofenac enabled local treatment of pain and inflammation while minimizing systemic absorption of diclofenac. SoluMatrix diclofenac, consisting of submicron particles of diclofenac free acid and a proprietary combination of excipients, was developed to provide analgesic efficacy at reduced doses associated with lower systemic absorption. This review illustrates how pharmaceutical technology has been used to modify the pharmacokinetic properties of diclofenac, leading to the creation of novel drug products with improved clinical utility.

Molecular basis for nonspecificity of nonsteroidal anti-inflammatory drugs (NSAIDs)

Inhibition of the production of inflammatory mediators by the action of nonsteroidal anti-inflammatory drugs (NSAIDs) is highly accredited to their recognition of cyclooxygenase enzymes. Along with inflammation relief, however, NSAIDs also cause adverse effects. Although NSAIDs strongly inhibit enzymes of the prostaglandin synthesis pathways, several other proteins also serve as fairly potent targets for these drugs. Based on their recognition pattern, these receptors are categorised as enzymes modifying NSAIDs, noncatalytic proteins binding to NSAIDs and enzymes with catalytic functions that are inhibited by NSAIDs. The extensive binding of NSAIDs is responsible for their limited in vivo efficacy as well as the large spectrum of their effects. The biochemical nature of drugs binding to multiple protein targets and its implications on physiology are discussed.

[Postoperative non-opioid analgesics management]

Morphine, which is known as the reference analgesic, has shown its limits. Reducing morphine consumption and multimodal analgesia are integral parts of a modern management of postoperative pain. Combination of several analgesics aims for improving pain control and the ratio between the analgesic effect and the side effects. Nefopam, paracetamol, non-steroids anti-inflammatory drugs and steroids are the most frequently prescribed non-opioid analgesics in France. They can be administered alone or in combination with or without morphine in the postoperative setting. The analgesic benefit of each of these agents and their associations is variable and described in details in this manuscript.

Acetylsalicylic acid does not alter thermo-effector responses during mild whole-body passive heat stress in young men

Acetylsalicylic acid (ASA), aspirin, exerts potent systemic effects that may interfere with normal thermo-effector responses. We investigated the influence of commonly ingested ASA doses on measures of skin blood flow (SkBF) and local sweat rate (SR) during whole-body, passive heat stress. Seven male participants completed counter-balanced trials to compare ASA treatments (single dose 325 mg or 4 consecutive days 81 mg (4-d 81 mg)) to control (no ASA). Laser-Doppler flowmetry provided an index of SkBF. A ventilated capsule measured local sweat rate via capacitance hygrometry. Mean body temperature ([Formula: see text]) was increased by 1 °C above baseline using a water-perfused suit. [Formula: see text] was similar at the onset of cutaneous vasodilation among trials. Cutaneous vascular conductance, expressed as a percentage change from baseline, was not different among trials. Additionally, [Formula: see text] at the onset of local SR and SR sensitivity did not differ among trials. While ASA has previously been shown to influence SkBF during heat stress, it is possible our cohort's relatively young age may have contributed to our dissimilar results.

Comparison of selective and non selective cyclo-oxygenase 2 inhibitors in experimental colitis exacerbation: role of leukotriene B4 and superoxide dismutase

CONTEXT

Nonsteroidal anti-inflammatory drugs are considered one of the most important causes of reactivation of inflammatory bowel disease. With regard to selective cyclo-oxygenase 2 inhibitors, the results are controversial in experimental colitis as well as in human studies.

OBJECTIVES

The aim this study is to compare nonsteroidal anti-inflammatory drugs effects, selective and non selective cyclo-oxygenase 2 inhibitors, in experimental colitis and contribute to the understanding of the mechanisms which nonsteroidal anti-inflammatory drugs provoke colitis exacerbation.

METHODS

Six groups of rats: without colitis, with colitis, and colitis treated with celecoxib, ketoprofen, indometacin or diclofenac. Survival rates, hemoglobin, plasmatic albumin, colonic tissue of interleukin-1ß, interleukin-6, tumor necrosis factor alpha, prostaglandin E2, catalase, superoxide dismutase, thiobarbituric acid-reactive substances, chemiluminescence induced by tert-butil hydroperoxides, and tissue and plasmatic leukotriene B4 were determined.

RESULTS

The groups treated with diclofenac or indometacin presented lower survival rates, hemoglobin and albumin, higher tissue and plasmatic leukotriene B4 and tissue superoxide dismutase than the group treated with celecoxib. Ketoprofen presented an intermediary behavior between diclofenac/indometacin and celecoxib, concerning to survival rate and albumin. The groups without colitis, with colitis and with colitis treated with celecoxib showed leukotriene B4 and superoxide dismutase lower levels than the groups treated with nonselective cyclo-oxygenase 2 inhibitors.

CONCLUSIONS

Diclofenac and indometacin presented the highest degree of induced colitis exacerbation with nonsteroidal anti-inflammatory drugs, celecoxib did not show colitis exacerbation, and ketoprofen presented an intermediary behavior between diclofenac/indometacin and celecoxib. These results suggest that leukotriene B4 and superoxide dismutase can be involved in the exacerbation of experimental colitis by nonselective nonsteroidal anti-inflammatory drugs.

Intravenous non-opioid analgesia for peri- and postoperative pain management: a scientific review of intravenous acetaminophen and ibuprofen

Pain is a predictable consequence following operations, but the management of postoperative pain is another challenge for anesthesiologists and inappropriately controlled pain may lead to unwanted outcomes in the postoperative period. Opioids are indeed still at the mainstream of postoperative pain control, but solely using only opioids for postoperative pain management may be connected with risks of complications and adverse effects. As a consequence, the concept of multimodal analgesia has been proposed and is recommended whenever possible. Acetaminophen is one of the most commonly used analgesic and antipyretic drug for its good tolerance and high safety profiles. The introduction of intravenous form of acetaminophen has led to a wider flexibility of its use during peri- and postoperative periods, allowing the early initiation of multimodal analgesia. Many studies have revealed the efficacy, safety and opioid sparing effects of intravenous acetaminophen. Intravenous ibuprofen has also shown to be well tolerated and demonstrated to have significant opioid sparing effects during the postoperative period. However, the number of randomized controlled trials confirming the efficacy and safety is small and should be used in caution in certain group of patients. Intravenous acetaminophen and ibuprofen are important options for multimodal postoperative analgesia, improving pain and patient satisfaction.

Gastrointestinal injury associated with NSAID use: a case study and review of risk factors and preventative strategies

Nonsteroidal anti-inflammatory drugs (NSAIDs) are effective anti-inflammatory and analgesic agents and are among the most commonly used classes of medications worldwide. However, their use has been associated with potentially serious dose-dependent gastrointestinal (GI) complications such as upper GI bleeding. GI complications resulting from NSAID use are among the most common drug side effects in the United States, due to the widespread use of NSAIDs. The risk of upper GI complications can occur even with short-term NSAID use, and the rate of events is linear over time with continued use. Although gastroprotective therapies are available, they are underused, and patient and physician awareness and recognition of some of the factors influencing the development of NSAID-related upper GI complications are limited. Herein, we present a case report of a patient experiencing a gastric ulcer following NSAID use and examine some of the risk factors and potential strategies for prevention of upper GI mucosal injuries and associated bleeding following NSAID use. These risk factors include advanced age, previous history of GI injury, and concurrent use of medications such as anticoagulants, aspirin, corticosteroids, and selective serotonin reuptake inhibitors. Strategies for prevention of GI injuries include anti-secretory agents, gastroprotective agents, alternative NSAID formulations, and nonpharmacologic therapies. Greater awareness of the risk factors and potential therapies for GI complications resulting from NSAID use could help improve outcomes for patients requiring NSAID treatment.

Thiazole derivatives as inhibitors of cyclooxygenases in vitro and in vivo

Cyclooxygenases (COXs) are important membrane-bound heme containing enzymes important in platelet activation and inflammation. COX-1 is constitutively expressed in most cells whereas COX-2 is an inducible isoform highly expressed in inflammatory conditions. Studies have been carried out to evaluate thiazole derivatives as anti-inflammatory molecules. In this study, we investigated the in vitro and in vivo effects of two novel thiazole derivatives compound 1 (N-[4-(4-hydroxy-3-methoxyphenyl)-1,3-thiazol-2-yl] acetamide) and compound 2 (4-(2-amino-1,3-thiazol-4-yl)-2-methoxyphenol) on prostaglandin E2 (PGE2) production and COX activity in inflammatory settings. Our results reveal a potent inhibition of both compound 1 (IC50 9.01±0.01µM) and 2 (IC50 11.65±6.20µM) (Mean±S.E.M.) on COX-2-dependent PGE2 production. We also determined whether COX-1 activity was inhibited. Using cells stably over-expressing COX-1 and human blood platelets, we showed that compound 1 is a specific inhibitor of COX-1 with IC50 (5.56×10(-8)±2.26×10(-8)µM), whereas compound 2 did not affect COX-1. Both compounds exhibit anti-inflammatory effect in the dorsal air pouch model of inflammation as shows by inhibition of PGE2 secretion. Modeling analysis of docking in the catalytic site of COX-1 or COX-2 further confirmed the difference in the effect of these two compounds. In conclusion, this study contributes to the design of new anti-inflammatory agents and to the understanding of cyclooxygenase inhibition by thiazole.

NSAIDs: learning new tricks from old drugs

Nonsteroidal anti-inflammatory drugs (NSAIDs) comprise a heterogeneous group of pharmacological agents used for the symptomatic treatment of fever, pain, and inflammation. Although the main mechanism of action of NSAIDs consists of inhibiting prostaglandin synthesis by blocking the enzyme cyclooxygenase (COX), clinical, and experimental data strongly indicate the existence of additional mechanisms. Some of the COX-independent effects are related to the ability of NSAIDs to penetrate biological membranes and disrupt important molecular interactions necessary for a wide array of cellular functions, including cell adhesion. These effects, in particular those that interfere with L-selectin function in neutrophils during the inflammatory response, may contribute to the anti-inflammatory properties that NSAIDs exert in vivo. Recent contributions in this field have shown that the anti-L-selectin effect of NSAIDs is related to the NADPH-oxidase-dependent generation of superoxide anion at the plasma membrane. These findings might represent a novel approach for developing new and effective anti-inflammatory compounds with a better safety profile than the currently available NSAIDs.

Prediction of the potency of mammalian cyclooxygenase inhibitors with ensemble proteochemometric modeling

Cyclooxygenases (COX) are present in the body in two isoforms, namely: COX-1, constitutively expressed, and COX-2, induced in physiopathological conditions such as cancer or chronic inflammation. The inhibition of COX with non-steroideal anti-inflammatory drugs (NSAIDs) is the most widely used treatment for chronic inflammation despite the adverse effects associated to prolonged NSAIDs intake. Although selective COX-2 inhibition has been shown not to palliate all adverse effects (e.g. cardiotoxicity), there are still niche populations which can benefit from selective COX-2 inhibition. Thus, capitalizing on bioactivity data from both isoforms simultaneously would contribute to develop COX inhibitors with better safety profiles. We applied ensemble proteochemometric modeling (PCM) for the prediction of the potency of 3,228 distinct COX inhibitors on 11 mammalian cyclooxygenases. Ensemble PCM models ([Formula: see text], and RMSEtest = 0.71) outperformed models exclusively trained on compound ([Formula: see text], and RMSEtest = 1.09) or protein descriptors ([Formula: see text] and RMSEtest = 1.10) on the test set. Moreover, PCM predicted COX potency for 1,086 selective and non-selective COX inhibitors with [Formula: see text] and RMSEtest = 0.76. These values are in agreement with the maximum and minimum achievable [Formula: see text] and RMSEtest values of approximately 0.68 for both metrics. Confidence intervals for individual predictions were calculated from the standard deviation of the predictions from the individual models composing the ensembles. Finally, two substructure analysis pipelines singled out chemical substructures implicated in both potency and selectivity in agreement with the literature. Graphical AbstractPrediction of uncorrelated bioactivity profiles for mammalian COX inhibitors with Ensemble Proteochemometric Modeling.

Improving acute pain management in emergency medicine

Undertreatment of pain (oligoanalgesia) in the emergency department is common, and it negatively impacts patient care. Both failure of appropriate pain assessment and the potential for unsafe analgesic use contribute to the problem. As a result, achieving satisfactory analgesia while minimizing side effects remains particularly challenging for emergency physicians, both in the emergency department and after a patient is discharged. Improvements in rapid pain assessment and in evaluation of noncommunicative populations may result in a better estimation of which patients require analgesia and how much pain is present. New formulations of available treatments, such as rapidly absorbed, topical, or intranasal nonsteroidal anti-inflammatory drug formulations or intranasal opioids, may provide effective analgesia with an improved risk-benefit profile. Other pharmacological therapies have been shown to be effective for certain pain modalities, such as the use of antidepressants for musculoskeletal pain, γ-aminobutyric acid agonists for neuropathic and postsurgical pain, antipsychotics for headache, and topical capsaicin for neuropathic pain. Nonpharmacological methods of pain control include the use of electrical stimulation, relaxation therapies, psychosocial/manipulative therapies, and acupuncture. Tailoring of available treatment options to specific pain modalities, as well as improvements in pain assessment, treatment options, and formulations, may improve pain control in the emergency department setting and beyond.

Marginally designed new profen analogues have the potential to inhibit cyclooxygenase enzymes

The current structure-activity relationship of profens (i.e., 2-arylpropionic acid derivatives, a class of non-steroidal anti-inflammatory drugs) discusses the importance of α-monomethyl substitution on these compounds, since the activities obtained through their corresponding arylacetic acid derivatives (i.e., α-demethylated derivatives) or α,α-dimethyl-substituted compounds are less than what is observed for the parent profens. Unfortunately, this implies a generalization in structure-activity relationships of profens in such a way that a mono-(non-methyl)alkyl group or dialkyl substituent replaced at the α-position of a profen analogue results in abolished activity. Therefore, within this study, we aimed to question this generalization employing ibuprofen, flurbiprofen, and naproxen as model compounds. A series of α-(non-methyl)alkyl-substituted ibuprofen and flurbiprofen analogues as well as α,α-dialkyl-substituted ibuprofen, flurbiprofen, and naproxen derivatives were synthesized and screened for their potential to inhibit cyclooxygenase enzymes. In addition, since profens have negligible potential to inhibit lipoxygenase enzymes, the effect of such derivatization was also questioned in lipoxygenase inhibition assays. The findings only partially agreed with the current structure-activity approach of profens and the activity results of some compounds were found as beyond ordinary.

Multiple Colon Ulcers with Typical Small Intestinal Lesions Induced by Non-Steroidal Anti-Inflammatory Drugs

The diagnosis of NSAID-induced colon ulcers is difficult when the distribution or endoscopic findings are not typical. An 83-year-old woman was transferred to our hospital for hemorrhagic diarrhea. Colonoscopy showed multiple ulcers in the entire colon, particularly longitudinal ulcers in the transverse colon. These were unusual for NSAID-induced colopathy, although she had been on meloxicam. However, capsule endoscopy revealed multiple scars and erosions, characteristic of NSAIDs users. The final diagnosis was NSAID-induced enteropathy, and all lesions were in remission after meloxicam discontinuation. We herein emphasize the value of an endoscopic assessment of the entire digestive tract in the diagnosis of NSAID-induced mucosal lesions.

Synthesis, 3D pharmacophore, QSAR and docking studies of novel quinazoline derivatives with nitric oxide release moiety as preferential COX-2 inhibitors

Four novel series of quinazoline derivatives IIIa–c, VIa–c and their NO-hybrid molecules as nitrate esters Va–c and VIIIa–c have been synthesized and evaluated for their anti-inflammatory activity in vivo and in vitro.

Synthesis and evaluation of new benzimidazole-based COX inhibitors: a naproxen-like interaction detected by STD-NMR

Non-steroidal anti-inflammatory drugs exert their pharmacological activity through inhibition of cyclooxygenase 1 and 2 (COX-1 and COX-2).

International Union of Basic and Clinical Pharmacology. XCI. structure, function, and pharmacology of acid-sensing ion channels and the epithelial Na+ channel

The epithelial Na(+) channel (ENaC) and the acid-sensing ion channels (ASICs) form subfamilies within the ENaC/degenerin family of Na(+) channels. ENaC mediates transepithelial Na(+) transport, thereby contributing to Na(+) homeostasis and the maintenance of blood pressure and the airway surface liquid level. ASICs are H(+)-activated channels found in central and peripheral neurons, where their activation induces neuronal depolarization. ASICs are involved in pain sensation, the expression of fear, and neurodegeneration after ischemia, making them potentially interesting drug targets. This review summarizes the biophysical properties, cellular functions, and physiologic and pathologic roles of the ASIC and ENaC subfamilies. The analysis of the homologies between ENaC and ASICs and the relation between functional and structural information shows many parallels between these channels, suggesting that some mechanisms that control channel activity are shared between ASICs and ENaC. The available crystal structures and the discovery of animal toxins acting on ASICs provide a unique opportunity to address the molecular mechanisms of ENaC and ASIC function to identify novel strategies for the modulation of these channels by pharmacologic ligands.

Evidence that links loss of cyclooxygenase-2 with increased asymmetric dimethylarginine: novel explanation of cardiovascular side effects associated with anti-inflammatory drugs

Supplemental Digital Content is available in the text.

Background—

Cardiovascular side effects associated with cyclooxygenase-2 inhibitor drugs dominate clinical concern. Cyclooxygenase-2 is expressed in the renal medulla where inhibition causes fluid retention and increased blood pressure. However, the mechanisms linking cyclooxygenase-2 inhibition and cardiovascular events are unknown and no biomarkers have been identified.

Methods and Results—

Transcriptome analysis of wild-type and cyclooxygenase-2^−/− mouse tissues revealed 1 gene altered in the heart and aorta, but >1000 genes altered in the renal medulla, including those regulating the endogenous nitric oxide synthase inhibitors asymmetrical dimethylarginine (ADMA) and monomethyl-l-arginine. Cyclo-oxygenase-2^−/− mice had increased plasma levels of ADMA and monomethyl-l-arginine and reduced endothelial nitric oxide responses. These genes and methylarginines were not similarly altered in mice lacking prostacyclin receptors. Wild-type mice or human volunteers taking cyclooxygenase-2 inhibitors also showed increased plasma ADMA. Endothelial nitric oxide is cardio-protective, reducing thrombosis and atherosclerosis. Consequently, increased ADMA is associated with cardiovascular disease. Thus, our study identifies ADMA as a biomarker and mechanistic bridge between renal cyclooxygenase-2 inhibition and systemic vascular dysfunction with nonsteroidal anti-inflammatory drug usage.

Conclusions—

We identify the endogenous endothelial nitric oxide synthase inhibitor ADMA as a biomarker and mechanistic bridge between renal cyclooxygenase-2 inhibition and systemic vascular dysfunction.

Pharmacokinetic properties and tolerability of low-dose SoluMatrix diclofenac

PURPOSE

This study compared the pharmacokinetic properties and safety profile of low-dose (18- and 35-mg) diclofenac capsules manufactured using SoluMatrix Fine Particle Technology (Trademark of iCeutica Inc. (Philadelphia, Pennsylvania), and the technology is licensed to Iroko Pharmaceuticals, LLC (Philadelphia, Pennsylvania) for exclusive use in NSAIDs), which produces submicron-sized drug particles with enhanced dissolution properties, to those of diclofenac potassium immediate-release (IR) 50-mg tablets.

METHODS

This Phase 1, single-center, randomized, open-label, single-dose crossover study was conducted in 40 healthy volunteers. Subjects received, in randomized order, SoluMatrix diclofenac 18- or 35-mg capsules in the fasting condition, SoluMatrix diclofenac 35-mg capsules under fed conditions, and diclofenac potassium IR 50-mg tablets under fasting and fed conditions. Pharmacokinetic parameters (T(max), C(max), AUC(0-t), AUC(0-∞)) were calculated from the concentrations of diclofenac in the plasma. Absorption, food effect, and dose proportionality were determined using a mixed-model ANOVA for C(max), AUC(0-t), AUC(0-∞). Tolerability was assessed by recording adverse events, physical examination findings, vital sign measurements: clinical laboratory test results.

FINDINGS

Overall, 35 healthy volunteers aged 18 to 52 years completed the study. The mean age of the subjects was 33.4 years, and approximately half were men (47.5%). Median T(max) values were similar between the low-dose SoluMatrix diclofenac 35-mg capsules and the diclofenac potassium IR 50-mg tablets (both, ~1.0 hour). The mean maximum plasma concentration (C(max)) after the administration of low-dose SoluMatrix diclofenac 35-mg capsules was 26% lower than that with diclofenac potassium IR 50-mg tablets under fasting conditions (868.72 vs 1194.21 ng/mL). The administration of low-dose SoluMatrix diclofenac 35-mg capsules was associated with a 23% lower overall systemic exposure compared with that of diclofenac potassium IR 50-mg tablets under fasting conditions. Food decreased the rate but not the overall extent of absorption of SoluMatrix diclofenac. No serious AEs and no clinically significant abnormalities in physical examination findings, including vital sign measurements, or clinical laboratory test results, were noted during this study.

IMPLICATIONS

The pharmacokinetic properties of low-dose SoluMatrix diclofenac capsules in the healthy volunteers in this study suggest rapid diclofenac absorption as measured by T(max). Low-dose SoluMatrix diclofenac capsules represent a potential option for the management of acute and osteoarthritis-related pain.

Phospho-NSAIDs have enhanced efficacy in mice lacking plasma carboxylesterase: implications for their clinical pharmacology

PURPOSE

The purpose of the study was to evaluate the metabolism, pharmacokinetics and efficacy of phospho-NSAIDs in Ces1c-knockout mice.

METHODS

Hydrolysis of phospho-NSAIDs by Ces1c was investigated using Ces1c-overexpressing cells. The rate of phospho-NSAID hydrolysis was compared between wild-type, Ces1c+/- and Ces1c-/- mouse plasma in vitro, and the effect of plasma Ces1c on the cytotoxicity of phospho-NSAIDs was evaluated. Pharmacokinetics of phospho-sulindac was examined in wild-type and Ces1c-/- mice. The impact of Ces1c on the efficacy of phospho-sulindac was investigated using lung and pancreatic cancer models in vivo.

RESULTS

Phospho-NSAIDs were extensively hydrolyzed in Ces1c-overexpressing cells. Phospho-NSAID hydrolysis in wild-type mouse plasma was 6-530-fold higher than that in the plasma of Ces1c-/- mice. Ces1c-expressing wild-type mouse serum attenuated the in vitro cytotoxicity of phospho-NSAIDs towards cancer cells. Pharmacokinetic studies of phospho-sulindac using wild-type and Ces1c-/- mice demonstrated 2-fold less inactivation of phospho-sulindac in the latter. Phospho-sulindac was 2-fold more efficacious in inhibiting the growth of lung and pancreatic carcinoma in Ces1c -/- mice, as compared to wild-type mice.

CONCLUSIONS

Our results indicate that intact phospho-NSAIDs are the pharmacologically active entities and phospho-NSAIDs are expected to be more efficacious in humans than in rodents due to their differential expression of carboxylesterases.

The therapeutic use of analgesics in patients with liver cirrhosis: a literature review and evidence-based recommendations

CONTEXT

Pain management in cirrhotic patients is a major clinical challenge for medical professionals. Unfortunately there are no concrete guidelines available regarding the administration of analgesics in patients with liver cirrhosis. In this review we aimed to summarize the available literature and suggest appropriate evidence-based recommendations regarding to administration of these drugs.

EVIDENCE ACQUISITION

An indexed MEDLINE search was conducted in July 2014, using keywords "analgesics", "hepatic impairment", "cirrhosis", "acetaminophen or paracetamol", "NSAIDs or nonsteroidal anti-inflammatory drugs", "opioid" for the period of 2004 to 2014. All randomized clinical trials, case series, case report and meta-analysis studies with the above mentioned contents were included in review process. In addition, unpublished information from the Food and Drug Administration are included as well.

RESULTS

Paracetamol is safe in patients with chronic liver disease but a reduced dose of 2-3 g/d is recommended for long-term use. Non-steroidal anti-inflammatory drugs (NSAIDs) are best avoided because of risk of renal impairment, hepatorenal syndrome, and gastrointestinal hemorrhage. Most opioids can have deleterious effects in patients with cirrhosis. They have an increased risk of toxicity and hepatic encephalopathy. They should be administrated with lower and less frequent dosing in these patients and be avoided in patients with a history of encephalopathy or addiction to any substance.

CONCLUSIONS

No evidence-based guidelines exist on the use of analgesics in patients with liver disease and cirrhosis. As a result pain management in these patients generates considerable misconception among health care professionals, leading under-treatment of pain in this population. Providing concrete guidelines toward the administration of these agents will lead to more efficient and safer pain management in this setting.

Flavonoid fraction of Bergamot juice reduces LPS-induced inflammatory response through SIRT1-mediated NF-κB inhibition in THP-1 monocytes

Plant polyphenols exert anti-inflammatory activity through both anti-oxidant effects and modulation of pivotal pro-inflammatory genes. Recently, Citrus bergamia has been studied as a natural source of bioactive molecules with antioxidant activity, but few studies have focused on molecular mechanisms underlying their potential beneficial effects. Several findings have suggested that polyphenols could influence cellular function by acting as activators of SIRT1, a nuclear histone deacetylase, involved in the inhibition of NF-κB signaling. On the basis of these observations we studied the anti-inflammatory effects produced by the flavonoid fraction of the bergamot juice (BJe) in a model of LPS-stimulated THP-1 cell line, focusing on SIRT1-mediated NF-κB inhibition. We demonstrated that BJe inhibited both gene expression and secretion of LPS-induced pro-inflammatory cytokines (IL-6, IL-1β, TNF-α) by a mechanism involving the inhibition of NF-κB activation. In addition, we showed that BJe treatment reversed the LPS-enhanced acetylation of p65 in THP-1 cells. Interestingly, increasing concentrations of Sirtinol were able to suppress the inhibitory effect of BJe via p65 acetylation, underscoring that NF-κB-mediated inflammatory cytokine production may be directly linked to SIRT1 activity. These results suggest that BJe may be useful for the development of alternative pharmacological strategies aimed at reducing the inflammatory process.

Diclofenac potassium powder for oral solution: a review of its use in patients with acute migraine

Diclofenac potassium powder for oral solution (Voltfast(®), Catafast(®), Cambia(®); hereafter referred to as diclofenac potassium powder) is a non-steroidal anti-inflammatory drug (NSAID), and is indicated for the acute treatment of migraine. This article reviews the pharmacological properties of diclofenac potassium powder and its efficacy and tolerability in patients with acute migraine. Diclofenac potassium powder was clinically efficacious and generally well tolerated in placebo-controlled trials in patients with this indication; it was more effective than diclofenac potassium tablets with regard to the primary endpoint of 2-h pain relief as well as in several important secondary endpoints, such as time to onset of analgesic action. The oral powder-for-solution formulation of diclofenac potassium is a useful option in the acute treatment of migraine with or without aura.

Formulation of diclofenac for dermal delivery

Diclofenac (DF) was first synthesized in the 1960's and is currently available as ophthalmic, oral, parenteral, rectal and skin preparations. This review focuses on the administration of DF to the skin. As a member of the non-steroidal anti-inflammatory (NSAID) group of drugs the primary indications of DF are for the management of inflammation and pain but it is also used to treat actinic keratosis. The specific aims of this paper are to: (i) provide an overview of the pharmacokinetics and metabolism of DF following oral and topical administration; (ii) examine critically the various formulation approaches which have been investigated to enhance dermal delivery of DF; and (iii) identify new formulation strategies for enhanced DF skin penetration.

Perioperative nonselective non-steroidal anti-inflammatory drugs are not associated with anastomotic leakage after colorectal surgery

INTRODUCTION

Recent evidence raises concern about the use of perioperative non-steroidal anti-inflammatory drug (NSAID) use after colorectal resection. The purpose of this retrospective cohort study was to investigate the relationship between perioperative ketorolac use and anastomotic leakage after colorectal surgery.

METHODS

A retrospective review (2004-2011) was performed on patients who underwent elective colorectal surgery. Univariate analysis and multivariate logistic regression were used to evaluate the association between patients who did not receive any NSAIDs and those who received ketorolac within the first 5 days perioperatively and leak rate.

RESULTS

A total of 731 patients were identified as having resection with primary anastomosis: 376 (51.4 %) received no NSAIDs and 355 (48.6 %) received ketorolac perioperatively within 5 days after their surgery. There were 24 (3.3 %) leaks, with 12 in both the no NSAIDs (3.2 %) and ketorolac (3.4 %) groups, odds ratio (OR) 1.06 (0.43, 2.62; p = 0.886). Adjusting for smoking, steroid use, and age, there remained no significant difference between ketorolac use and leakage, OR 1.21 (0.52, 2.84; p = 0.660). In our multivariate model, only smoking was a significant predictor of postoperative leak, OR 3.34 (1.30, 8.62; p = 0.021).

CONCLUSIONS

There does not appear to be a significant association between perioperative ketorolac use and anastomotic leakage after colorectal surgery. However, further prospective studies are needed to confirm our findings before definitive guidelines on NSAID use perioperatively can be recommended.

The pharmacokinetics and in vitro/ex vivo cyclooxygenase selectivity of parecoxib and its active metabolite valdecoxib in cats

Parecoxib (PX) is an injectable prodrug of valdecoxib (VX, which is a selective cyclo-oxyganase-2 (COX-2)) inhibitor licensed for humans. The aim of the present study was to evaluate pharmacokinetics and in vitro/ex vivo cyclooxygenase selectivity of PX and VX in cats. In a whole blood in vitro study, PX did not affect either COX enzymes whereas VX revealed a COX-2 selective inhibitory effect in feline whole blood. The IC50 values of VX for COX-2 and COX-1 were 0.45 and 38.6 µM, respectively. Six male cats were treated with 2.5 mg/kg of PX by intramuscular injection. PX was rapidly converted to VX with a relatively short half-life of 0.4 h. VX achieved peak plasma concentration (2.79 ± 1.59 µg/mL) at 7 h following PX injection. The mean residence times for PX and VX were 0.43 ± 0.15 and 5.94 ± 0.88 h, respectively. In the ex vivo study, PX showed a COX-2 inhibition rate of about 70% in samples taken at 1, 2, 4 and 10 h after injection, with a significant difference compared to the control. In contrast, COX-1 was slightly inhibited, ranging from 0.7% to 9.7% of the control inhibition rate without any significant difference for 24 h after PX administration. The preliminary findings of the present research appear promising and encourage further studies to investigate whether PX can be successfully used in feline medicine.

SERCaMP: a carboxy-terminal protein modification that enables monitoring of ER calcium homeostasis

Depletion of ER calcium can lead to cell death and is implicated in numerous diseases. Secreted ER calcium-monitoring proteins (SERCaMPs) are secreted in response to ER calcium depletion. SERCaMPs identified ER calcium depletion in primary neurons exposed to glutamate, hyperthermia, and coxibs and in rat liver after a single exposure to thapsigargin.

Endoplasmic reticulum (ER) calcium homeostasis is disrupted in diverse pathologies, including neurodegeneration, cardiovascular diseases, and diabetes. Temporally defining calcium dysregulation during disease progression, however, has been challenging. Here we describe secreted ER calcium-monitoring proteins (SERCaMPs), which allow for longitudinal monitoring of ER calcium homeostasis. We identified a carboxy-terminal modification that is sufficient to confer release of a protein specifically in response to ER calcium depletion. A Gaussia luciferase (GLuc)–based SERCaMP provides a simple and sensitive method to monitor ER calcium homeostasis in vitro or in vivo by analyzing culture medium or blood. GLuc-SERCaMPs revealed ER calcium depletion in rat primary neurons exposed to various ER stressors. In vivo, ER calcium disruption in rat liver was monitored over several days by repeated sampling of blood. Our results suggest that SERCaMPs will have broad applications for the long-term monitoring of ER calcium homeostasis and the development of therapeutic approaches to counteract ER calcium dysregulation.

Role of prostaglandins in spinal transmission of the exercise pressor reflex in decerebrated rats

Previous studies found that prostaglandins in skeletal muscle play a role in evoking the exercise pressor reflex; however the role played by prostaglandins in the spinal transmission of the reflex is not known. We determined, therefore, whether or not spinal blockade of cyclooxygenase (COX) activity and/or spinal blockade of endoperoxide (EP) 2 or 4 receptors attenuated the exercise pressor reflex in decerebrated rats. We first established that intrathecal doses of a non-specific COX inhibitor Ketorolac (100 μg in 10 μl), a COX-2-specific inhibitor Celecoxib (100 μg in 10 μl), an EP2 antagonist PF-04418948 (10 μg in 10 μl), and an EP4 antagonist L-161,982 (4 μg in 10 μl) effectively attenuated the pressor responses to intrathecal injections of arachidonic acid (100 μg in 10 μl), EP2 agonist Butaprost (4 ng in 10 μl), and EP4 agonist TCS 2510 (6.25 μg in 2.5 μl), respectively. Once effective doses were established, we statically contracted the hind limb before and after intrathecal injections of Ketorolac, Celecoxib, the EP2 antagonist and the EP4 antagonist. We found that Ketorolac significantly attenuated the pressor response to static contraction (before Ketorolac: 23 ± 5 mmHg, after Ketorolac 14 ± 5 mmHg; p<0.05) whereas Celecoxib had no effect. We also found that 8 μg of L-161,982, but not 4 μg of L-161,982, significantly attenuated the pressor response to static contraction (before L-161,982: 21 ± 4 mmHg, after L-161,982 12 ± 3 mmHg; p<0.05), whereas PF-04418948 (10 μg) had no effect. We conclude that spinal COX-1, but not COX-2, plays a role in evoking the exercise pressor reflex, and that the spinal prostaglandins produced by this enzyme are most likely activating spinal EP4 receptors, but not EP2 receptors.

Lung inflammatory response syndrome after cardiac-operations and treatment of lornoxicam

The majority of patients survive after extracorporeal circulation without any clinically apparent deleterious effects. However, disturbances exist in various degrees sometimes, which indicate the harmful effects of cardiopulmonary bypass (CPB) in the body. Several factors during extracorporeal circulation either mechanical dependent (exposure of blood to non-biological area) or mechanical independent (surgical wounds, ischemia and reperfusion, alteration in body temperature, release of endotoxins) have been shown to trigger the inflammatory reaction of the body. The complement activation, the release of cytokines, the leukocyte activation and accumulation as well as the production of several "mediators" such as oxygen free radicals, metabolites of arachidonic acid, platelet activating factors (PAF), nitric acid, and endothelin. The investigation continues today on the three metabolites of lornoxicam (the hydroxylated metabolite and two other metabolites of unknown chemical composition) to search for potential new pharmacological properties and activities.

COX-2 protects against atherosclerosis independently of local vascular prostacyclin: identification of COX-2 associated pathways implicate Rgl1 and lymphocyte networks

Cyxlo-oxygenase (COX)-2 inhibitors, including traditional nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with increased cardiovascular side effects, including myocardial infarction. We and others have shown that COX-1 and not COX-2 drives vascular prostacyclin in the healthy cardiovascular system, re-opening the question of how COX-2 might regulate cardiovascular health. In diseased, atherosclerotic vessels, the relative contribution of COX-2 to prostacyclin formation is not clear. Here we have used apoE(-/-)/COX-2(-/-) mice to show that, whilst COX-2 profoundly limits atherosclerosis, this protection is independent of local prostacyclin release. These data further illustrate the need to look for new explanations, targets and pathways to define the COX/NSAID/cardiovascular risk axis. Gene expression profiles in tissues from apoE(-/-)/COX-2(-/-) mice showed increased lymphocyte pathways that were validated by showing increased T-lymphocytes in plaques and elevated plasma Th1-type cytokines. In addition, we identified a novel target gene, rgl1, whose expression was strongly reduced by COX-2 deletion across all examined tissues. This study is the first to demonstrate that COX-2 protects vessels against atherosclerotic lesions independently of local vascular prostacyclin and uses systems biology approaches to identify new mechanisms relevant to development of next generation NSAIDs.

The effects of cyclooxygenase inhibitors on the gastric emptying and small intestine transit in the male rats following traumatic brain injury

OBJECTIVES

This study was carried out to investigate the effects of COX-2 selective inhibitor (Celecoxib) or non-selective COX inhibitor (Ibuprofen) on gastrointestinal motility.

MATERIALS AND METHODS

THE RATS WERE RANDOMLY DIVIDED INTO FIVE GROUPS INCLUDING: intact, sham, traumatic brain injury (TBI) group (intact rats under TBI), Celecoxib group (10 mg/kg), Ibuprofen group (10 mg/kg). Rats of the treatment groups received gavages at 1 hr before the TBI induction. The TBI was moderate and diffused using the Marmarou method. The gastric emptying and small intestine transit were measured by phenol red method.

RESULTS

The gastric emptying didn't change following TBI induction compared to intact group. The consumption of ibuprofen or celecoxib didn't have any effect on gastric emptying compared to sham group. TBI induction didn't have any effect on the intestinal transit. Also, there was no significant difference between ibuprofen or celecoxib consumption vs. sham group (P>0.05).

CONCLUSION

The COX-2 selective inhibitor (celecoxib) or non-selective COX inhibitor (ibuprofen) have no effects on gastric or small bowel transit. Further work is necessary to investigate the effects of non-selective COX inhibitors and their impact on gastrointestinal motility disorders.

Toward an optimal docking and free energy calculation scheme in ligand design with application to COX-1 inhibitors

Cyclooxygenase-1 (COX-1) is one of the main targets of most pain-relieving pharmaceuticals. Although the enzyme is well characterized, it is known to be a difficult target for automated molecular docking and scoring. We collected from the literature a structurally diverse set of 45 nonsteroidal anti-inflammatory drugs (NSAIDs) and COX-2-selective inhibitors (coxibs) with a wide range of binding affinities for COX-1. The binding of this data set to a homology model of human COX-1 was analyzed with different combinations of molecular docking algorithms, scoring functions, and the linear interaction energy (LIE) method for estimating binding affinities. It is found that the computational protocols for estimation of binding affinities are extremely sensitive to the initial orientations of the ligands in the binding pocket. To overcome this limitation, we propose a systematic exploration of docking poses using the LIE calculations as a postscoring function. This scheme yields predictions in excellent agreement with experiment, with a mean unsigned error of 0.9 kcal/mol for binding free energies and structures of high quality. A significant improvement of the results is also seen when averaging over experimental data from several independent measurements.

δ-Amyrone, a specific inhibitor of cyclooxygenase-2, exhibits anti-inflammatory effects in vitro and in vivo of mice

The whole plant of Sedum lineare Thunb has been used as traditional folk medicines for the treatment of sore throat, persistent hepatitis, jaundice and dysentery. δ-Amyrone (13(18)-Oleanen-3-one), a pentacyclic triterpene compound from S. lineare Thunb, was found to possess a potent anti-inflammatory effect in different inflammation model animals. Pretreatment with δ-Amyrone (i.p.) inhibited the ear edema in xylene-induced mouse ear edema. δ-Amyrone also decreased the level of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-6 (IL-6) and leukocyte numbers in acetic acid-induced peritonitis in vivo. To clarify the possible mechanism of δ-Amyrone, we investigated the effect of δ-Amyrone in lipopolysaccharide (LPS) induced peritoneal macrophages. The data indicated that δ-Amyrone notably inhibited IL-6, TNF-α and NO production. In addition, the result showed that δ-Amyrone may control the cyclooxygenase-2 (COX-2) regulation and not the cyclooxygenase-1 (COX-1) at protein levels. These results suggest that δ-Amyrone is a bioactive agent which possesses anti-inflammatory effects, which may be relevant to the regulation of COX-2.