Effect of 5-lipoxygenase inhibitor, VIA-2291 (Atreleuton), on epicardial fat volume in patients with recent acute coronary syndrome.

BACKGROUND AND AIMS: The association between inflammation and atherosclerosis has been well described in the literature. There is now mounting evidence in support of adipose tissue as a reservoir for inflammatory markers. Epicardial adipose tissue (EAT) has been shown to associate with coronary atherosclerosis and found to be a predictor of future adverse cardiovascular events. This study, VIA-EAT, assesses the change in epicardial fat volume (EFV) after treatment with an investigational anti-inflammatory agent (VIA-2291) in a cohort of post-acute coronary syndrome (ACS) patients. METHODS: This study is derived from a post-hoc analysis of a previously conducted randomized clinical trial (NCT00358826). Patients were recruited for a prospective, double-blind, multi-center randomized trial of a 5-lipooxygenase inhibitor or placebo in a 3:1 randomization, including doses of placebo, and 25 mg, 50 mg and 100 mg of active treatment. Cardiac computed tomography was performed at baseline and at 24 weeks after treatment with VIA-2291. EAT and pericardial adipose tissue (PAT) were measured using previously published methodology. A Pearson correlation test was used to determine the relationship between change in epicardial fat and change in plaque composition. RESULTS: We analyzed 54 pre- and post-treatment scans. There were no major differences between traditional cardiovascular risk factors among the 4 randomized study arms. There was a significant decrease in EAT and PAT in patients in the treatment arms vs. placebo, -3.0 ± 8.2mm3 and -3.9 ± 10.9mm3 vs. 1.7 ± 7.5mm3 and 1.4 ± 10.7mm3 (p = 0.001), respectively. The changes in EAT and PAT were more pronounced in patients taking 100 mg of the drug vs. placebo: 4.2 ± 9.6mm3, -7.6 ± 8.5mm3, p = 0.0001, respectively. In a subgroup analysis, reduction in epicardial fat volume correlated with reduction in total atherosclerotic plaque volume across all VIA treatment groups, r = 0.52 (p = 0.004). CONCLUSIONS: After adjustment for traditional cardiovascular risk factors including age, gender, body mass index, dyslipidemia and smoking, VIA-2291 decreases EAT and PAT in individuals with recent ACS. Treatment with the drug also appears to alter plaque volume and composition.

Ambient fine particulate matter inhibits 15-lipoxygenases to promote lung carcinogenesis.

BACKGROUND: Epidemiological observations have demonstrated that ambient fine particulate matter with dp < 2.5 µm (PM2.5) as the major factor responsible for the increasing incidence of lung cancer in never-smokers. However, there are very limited experimental data to support the association of PM2.5 with lung carcinogenesis and to compare PM2.5 with smoking carcinogens. METHODS: To study whether PM2.5 can contribute to lung tumorigenesis in a way similar to smoking carcinogen 4-methylnitrosamino-l-3-pyridyl-butanone (NNK) via 15-lipoxygenases (15-LOXs) reduction, normal lung epithelial cells and cancer cells were treated with NNK or PM2.5 and then epigenetically and post-translationally examined the cellular and molecular profiles of the cells. The data were verified in lung cancer samples and a mouse lung tumor model. RESULTS: We found that similar to smoking carcinogen NNK, PM2.5 significantly enhanced cell proliferation, migration and invasion, but reduced the levels of 15-lipoxygenases-1 (15-LOX1) and 15-lipoxygenases-2 (15-LOX2), both of which were also obviously decreased in lung cancer tissues. 15-LOX1/15-LOX2 overexpression inhibited the oncogenic cell functions induced by PM2.5/NNK. The tumor formation and growth were significantly higher/faster in mice implanted with PM2.5- or NNK-treated NCI-H23 cells, accompanied with a reduction of 15-LOX1/15-LOX2. Moreover, 15-LOX1 expression was epigenetically regulated at methylation level by PM2.5/NNK, while both 15-LOX1 and 15-LOX2 could be significantly inhibited by a set of PM2.5/NNK-mediated microRNAs. CONCLUSION: Collectively, PM2.5 can function as the smoking carcinogen NNK to induce lung tumorigenesis by inhibiting 15-LOX1/15-LOX2.

Synthesis, pharmacological screening and computational analysis of some 2-(1H-Indol-3-yl)-N'-[(un)substituted phenylmethylidene] acetohydrazides and 2-(1H-Indol-3-yl)-N'-[(un)substituted benzoyl/2-thienylcarbonyl]acetohydrazides.

The undertaken research was initiated by transforming 2-(1H-Indol-3-yl)acetic acid (1) in catalytic amount of sulfuric acid and ethanol to ethyl 2-(1H-Indol-3-yl)acetate (2), which was then reacted with hydrazine monohydrate in methanol to form 2-(1H-Indol-3-yl)acetohydrazide (3). Further, The reaction scheme was designed into two pathways where, first pathway involved The reaction of 3 with substituted aromatic aldehydes (4a-o) in methanol with few drops of glacial acetic acid to generate 2-(1H-Indol-3-yl)-N'-[(un)substitutedphenylmethylidene]acetohydrazides (5a-o) and in second pathway 3 was reacted with acyl halides (6a-e) in basic aqueous medium (pH 9-10) to afford 2-(1H-Indol-3-yl)-N'-[(un)substitutedbenzoyl/2-thienylcarbonyl]acetohydrazides (7a-e). All The synthesized derivatives were characterized by IR, EI-MS and 1H-NMR spectral techniques and evaluated for their anti-bacterial potentials against Gram positive and Gram negative bacterial strains and it was found that compounds 7a-d exhibited antibacterial activities very close to standard Ciprofloxacin. The synthesized derivatives demonstrated moderate to weak anti-enzymatic potential against α-Glucosidase and Butyrylcholinesterase (BChE) where, compounds 7c and 5c exhibited comparatively better inhibition against these enzymes respectively. Compounds 7a, 7d and 7e showed excellent anti-enzymatic potentials against Lipoxygenase (LOX) and their IC50 values were much lower than the reference standard Baicalein. Enzyme inhibitory activities were also supported by computational docking results. Compounds 5c, 7a, 7b and 7c also showed low values of % hemolytic activity as well, showing that these molecules were not toxic, indicating that these molecules can be utilized as potential therapeutic agents against inflammatory ailments.

Synthesis, biological evaluation, docking study and ulcerogenicity profiling of some novel quinoline-2-carboxamides as dual COXs/LOX inhibitors endowed with anti-inflammatory activity.

A series of novel quinoline-2-carboxamides 15-28 was synthesized and evaluated in vitro as dual COXs/LOX inhibitors. Compounds 19 and 27 exhibited the highest potency and selectivity for COX-2 inhibitory activity (IC50 = 1.21 and 1.13 µM, respectively; selectivity index (COX-1/COX-2) = 6.52 and 7.61, respectively) in comparison to the reference drug celecoxib (COX-2 IC50 = 0.88 µM; selectivity index (COX-1/COX-2) = 8.31). The anti-inflammatory activity of the newly synthesized compounds was further assessed in vivo using carrageenan induced paw edema assay. Interestingly, the in vitro results of COXs inhibitory assay were consistent with that of the in vivo assay where compounds 19 and 27 showed the highest anti-inflammatory activity with edema inhibition percentages of 59.38% and 65.03%, respectively compared to celecoxib (71.21%) after 5 h. Moreover, it was found that compounds 19 and 27 have a superior gastric safety profile comparable to indomethacin. The molecular docking study of compounds 19 and 27 into COX-2 active site suggested that these hits assumed binding pattern and interactions similar to that of bromocelecoxib (S-58) as a cocrystallized ligand explaining their remarkable COX-2 inhibitory activity and selectivity. Taken together, these results indicated that these derivatives are good leads for subsequent development into potential anti-inflammatory agents with least gastric damage.

Synthesis of new thiazolo-celecoxib analogues as dual cyclooxygenase-2/15-lipoxygenase inhibitors: Determination of regio-specific different pyrazole cyclization by 2D NMR.

Two new series of 1,5-diaryl pyrazoles (5a, 5b, 7a, 7b and 10) and 1,5-diaryl pyrazoline (12a and 12b) were prepared as both Cyclooxygenase-2 and 15-lipoxygenase inhibitors. Carrageenan-induced rat paw edema, ulcer index and anti-COX-1/COX-2 and 15-LOX inhibition assays were also included. Cyclization of different pyrazoles was discussed using 2D NMR such as HSQC, HMBC and NOSEY determinations. Compound 5a is more effective with ED50 = 0.98 and 3.98 µM against COX-2 and 15-lipoxygenase respectively, than the references celecoxib (1.54 µM) and meclofenamate sodium (5.64 µM).

A phase 2 randomized, double-blind, placebo-controlled study of the effect of VIA-2291, a 5-lipoxygenase inhibitor, on vascular inflammation in patients after an acute coronary syndrome.

OBJECTIVE: Arachidonate 5-lipoxygenase (5-LO) is a key enzyme in the synthesis of leukotrienes. VIA-2291 is a potent 5-LO inhibitor, which has been shown to reduce hsCRP and noncalcified coronary plaque volume following an acute coronary syndrome (ACS). We aim to evaluate the effect of VIA-2291 on vascular inflammation compared to placebo using FDG-PET. METHODS: A Phase II, randomized, double-blind, parallel-group study was conducted in 52 patients with recent ACS assigned 1:1 to either 100 mg VIA-2291 or placebo for 24 weeks. The primary outcome was the effect of VIA-2291 relative to placebo on arterial inflammation detected by (18)fluorodeoxyglucose positron emission tomography (FDG-PET) within the index vessel after 24 weeks of daily treatment, compared to baseline. RESULTS: VIA-2291 was relatively well tolerated and was associated with a significant inhibition of the potent chemo-attractant LTB4, with a mean inhibition of activity of 92.8% (p<0.0001) at 6 weeks in the VIA-2291 group, without further significant change in inhibition at 24 weeks. However, for VIA-2291 was not associated with significant difference in inflammation (target-to-background ratio) compared to placebo at 24 weeks or 6 weeks of treatment. Further, VIA-2291 was not associated with a significant reduction in hsCRP from baseline after either 6 or 24 weeks of treatment. CONCLUSIONS: VIA-2291 is well-tolerated and effectively reduces leukotriene production. However, inhibition of 5-LO with VIA-2291 is not associated with significant reductions in vascular inflammation (by FDG-PET) or in blood inflammatory markers. Accordingly, this study does not provide evidence to support a significant anti-inflammatory effect of VIA-2291 in patients with recent ACS.

Randomized trial of zileuton for treatment of COPD exacerbations requiring hospitalization.

RATIONALE: Leukotrienes have been implicated in the pathogenesis of acute exacerbations of COPD, but leukotriene modifiers have not been studied as a possible therapy for exacerbations. OBJECTIVE: We sought to test the safety and efficacy of adding oral zileuton (a 5-lipoxygenase inhibitor) to usual treatment for acute exacerbations of COPD requiring hospitalization. METHODS: Randomized double-blind, placebo-controlled, parallel group study of zileuton 600 mg orally, 4 times daily versus placebo for 14 days starting within 12 hours of hospital admission for COPD exacerbation. Primary outcome measure was hospital length of stay; secondary outcomes included treatment failure and biomarkers of leukotriene production. MAIN FINDINGS: Sixty subjects were randomized to zileuton and 59 to placebo (the study was stopped short of enrollment goals because of slow recruitment). There was no difference in hospital length of stay (3.75 +/- 2.19 vs. 3.86 +/- 3.06 days for zileuton vs. placebo, p = 0.39) or treatment failure (23% vs. 27% for zileuton vs. placebo, p = 0.63) despite a decline in urinary LTE(4) levels in the zileuton-treated group as compared to placebo at 24 hours (change in natural log-transformed ng/mg creatinine -1.38 +/- 1.19 vs. 0.14 +/- 1.51, p < 0.0001) and 72 hours (-1.32 +/- 2.08 vs. 0.26 +/- 1.93, p<0.006). Adverse events were similar in both groups. PRINCIPAL CONCLUSIONS: While oral zileuton during COPD exacerbations that require hospital admission is safe and reduces urinary LTE(4) levels, we found no evidence suggesting that this intervention shortened hospital stay, with the limitation that our sample size may have been insufficient to detect a modest but potentially meaningful clinical improvement.

Activity and potential role of licofelone in the management of osteoarthritis.

Osteoarthritis is the most common form of arthritis. It is a progressive joint disease associated with aging. It may be found in the knees, hips, or other joints. It is estimated that costs associated with osteoarthritis exceed 2% of the gross national product in developed countries. Nonsteroidal anti-inflammatory drugs (NSAIDs) are a mainstay in the treatment of inflammatory disease and are among the most widely used drugs worldwide. The main limitation in using NSAIDs consists in their side-effects, including gastrointestinal ulcerogenic activity and bronchospasm. The mechanism of action of these drugs is attributed to the inhibition of cyclooxygenase (COX), and, consequently, the conversion of arachidonic acid into prostaglandins. It is hypothesized that the undesirable side-effects of NSAIDs are due to the inhibition of COX-1 (constitutive isoform), whereas the beneficial effects are related to the inhibition of COX-2 (inducible isoform). Arachidonic acid can also be converted to leukotrienes (LTs) by the action of 5-lipoxygenase (5-LOX). Licofelone, a LOX/COX competitive inhibitor, decreases the production ofproinflammatory leukotrienes and prostaglandins (which are involved in the pathophysiology of osteoarthritis and in gastrointestinal (GI) damage induced by NSAIDs) and has the potential to combine good analgesic and anti-inflammatory effects with excellent GI tolerability. Preliminary data with this drug seem promising, but further well-designed clinical trials of this agent in the elderly will be necessary before a final evaluation is possible.

Clinical pattern of zileuton-associated liver injury: results of a 12-month study in patients with chronic asthma.

OBJECTIVE: Zileuton is a 5-lipoxygenase inhibitor approved by the US FDA in 1996 for the treatment of asthma in adults and children. During phase II/III clinical trials, zileuton was generally well tolerated, although elevations in ALT and AST levels were noted in some patients, and a single treated patient developed hepatocellular jaundice. To more fully characterise the hepatic effects of zileuton, and to establish appropriate monitoring guidelines, a 12-month open-label, safety surveillance study was conducted prior to FDA approval. PATIENTS AND METHODS: In this study, 2458 patients with asthma received zileuton 600mg four times daily in addition to usual asthma care, and 489 patients were treated with usual asthma care only. All patients had their liver biochemistry checked monthly for the first 5 months, and at months 7, 10 and 12 thereafter. RESULTS: A total of 109 patients (4.4%) receiving zileuton treatment had elevations in ALT levels to > or =3 x the upper limit of normal (ULN), including 31 patients (1.3%) who had levels elevated to > or =8 x ULN, compared with 5 of 480 patients in the usual care alone group (1.0%) who had levels elevated to > or =3 x ULN, of whom 1 (0.2%) had levels elevated to > or =8 x ULN. Elevations in ALT levels were generally not associated with increases in alkaline phosphatase and/or total bilirubin levels. Therefore, the hepatic injury was predominantly hepatocellular. The majority of elevations in ALT level to > or =3 x ULN (64.2%) in the zileuton-treated group occurred within the first 3 months of treatment. There was no correlation between the time of onset of ALT level elevation and the height of the peak ALT level observed. There was no overall difference in the occurrence of elevations in ALT level to > or =3 x ULN between men (4.5%) and women (4.7%), but more women than men experienced an ALT level > or =8 x ULN (1.8% vs 0.5%). Women aged > or =65 years appeared to be at higher risk of elevated ALT levels than those aged <65 years (a rate of 10.1% compared with 4.1%). Patients who experienced ALT levels of > or =3 x ULN but <5 x ULN were allowed to remain on treatment and 52.5% of these patients were able to continue zileuton therapy and experienced resolution of the elevation (a reduction in level to <2 x ULN). In each of the patients who discontinued treatment because of elevated ALT levels, the ALT level returned towards baseline, with a mean time to resolution (defined as a reduction in levels to <2 x ULN) of 4 weeks. No patient in this study developed clinically apparent jaundice or liver failure. Two patients (0.1%) experienced total bilirubin levels > or =1.5 x ULN in association with serum ALT levels exceeding 3 x ULN. CONCLUSIONS: This study established that liver chemistry monitoring is most effective in detecting elevation of ALT levels during the first 3 months of zileuton therapy and that with appropriate monitoring the risk of irreversible liver injury appears to be low.

The safety and efficacy of zileuton controlled-release tablets as adjunctive therapy to usual care in the treatment of moderate persistent asthma: a 6-month randomized controlled study.

This study was conducted to assess the safety and efficacy of zileuton controlled release [CR] 1,200 mg BID added to usual care (UC) in 926 patients with moderate asthma (619 patients randomized to zileuton CR and 307 to placebo). Sustained improvements in AM and PM peak expiratory flow (PEF) were observed in the zileuton CR group compared to placebo. The adverse event profile was similar in the two treatment groups. Eleven patients (1.8%) receiving zileuton CR and 2 (0.7%) receiving placebo experienced elevations of alanine aminotransferase (ALT) >or= 3X the upper limit of normal (ULN). These elevations typically occurred (81.8%) during the first 3 months of exposure and most resolved within 21 days after discontinuation.

The classical vs nonclassical NSAIDs: can the reduction in pain overcome the thrombotic risk?

The advent of cyclooxygenase-2 inhibitors has been both a blessing and a curse for pain management. An in-depth understanding of the biological molecules in the arachidonic acid metabolism may alleviate pain without risk.

Combined lipoxygenase/cyclo-oxygenase inhibition in the elderly: the example of licofelone.

One of the categories of drugs most frequently used by the elderly, and probably the most commonly self-prescribed class of drug in this age group, is NSAIDs. However, NSAIDs are one of the primary causes of adverse drug reactions and are notorious for their gastric toxicity. They also inhibit renal function and reduce the efficacy of diuretics and ACE inhibitors, drugs that are commonly used by elderly patients. Recent studies have shown that cyclo-oxygenase (COX)-2 is important in renal physiology. This means that selective COX-2 inhibitors, while undoubtedly safer than NSAIDs in terms of gastric toxicity, are not devoid of renal toxicity (in addition to their now clearly established adverse effects on coronary heart disease risk). Both the gastric and renal toxicities induced by traditional NSAIDs and selective COX-2 inhibitors seem to be related to inhibition of prostaglandin, but not leukotriene, synthesis. Maintaining the correct balance between prostaglandins and leukotrienes is essential for continuing good health, but both classes of mediators also play an important role in the pathogenesis of several diseases.Recently, a new class of anti-inflammatory drugs, the lipoxygenase (LOX)/COX inhibitors, has been developed as a means of simultaneously inhibiting the synthesis of prostaglandins, thromboxanes and leukotrienes. Inhibition of leukotriene synthesis increases anti-inflammatory efficacy, particularly in rheumatic diseases, while reducing the risk of gastric damage. The LOX/COX inhibitor licofelone, which is currently in phase III trials, is the first of this new class and in the most advanced stage of development. Preliminary data with this drug seem promising, but further well designed clinical trials of this agent in the elderly will be necessary before a final evaluation is possible.

The effects of a 5-lipoxygenase inhibitor on acute mountain sickness and urinary leukotriene e4 after ascent to high altitude.

BACKGROUND: Elevated urine and blood leukotriene levels have been reported after ascent to high altitude in association with acute mountain sickness (AMS) and high-altitude pulmonary edema. Zileuton is an inhibitor of the enzyme 5-lipoxygenase that catalyzes conversion of arachidonic acid to leukotrienes. Study objectives and design: The objectives of this randomized, double-blind, placebo-controlled clinical trial were to determine whether zileuton (600 mg po qid) is effective prophylaxis for AMS, and to measure the effect of ascent to high altitude and zileuton on urinary leukotriene E(4) levels. SETTING AND PARTICIPANTS: The study group consisted of volunteers from among climbers on the West Buttress of Mt. McKinley (Denali), Alaska. After baseline urine samples at sea level, subjects flew by airplane to 2,300 m, and then ascended to the 4,200-m camp in 5 to 10 days. MEASUREMENTS AND RESULTS: Using an enzyme immunoassay, urinary leukotriene E(4) was found to decrease after ascent to high altitude in both the zileuton and placebo groups. Urinary leukotriene E(4) in the zileuton group (n = 9) decreased from 67 +/- 35 pg/mg creatinine at sea level to 33 +/- 22 pg/mg creatinine at high altitude (p = 0.003) [mean +/- SD]. Urinary leukotriene E(4) in the placebo group (n = 9) decreased from 97 +/- 82 pg/mg creatinine at sea level to 44 +/- 21 pg/mg creatinine at high altitude (p = 0.045). One subject in the zileuton group and three subjects in the placebo group met Lake Louise criteria for AMS after arriving at 4,200 m (p = 0.257). CONCLUSIONS: Elevated leukotrienes are not associated with ascent to high altitude. In subjects with AMS, urinary leukotrienes were not elevated, suggesting that leukotrienes may not be a component of the pathophysiology of AMS. The low incidence of AMS and the small sample size in this study prevented determination of whether zileuton is effective prophylaxis for AMS.

Zileuton, a 5-lipoxygenase inhibitor, increases production of thromboxane A2 and platelet aggregation in patients with asthma.

Leukotrienes, generated from arachidonic acid via the lipoxygenase pathway, play an important role in the pathophysiology of asthma. Therefore, leukotriene inhibitors, such as Zileuton, are used in the treatment of asthma. However, thromboxanes, generated from arachidonic acid via the cyclooxygenase pathway, play an important role in platelet aggregation and thrombosis. Therefore, we studied whether Zileuton, by shifting arachidonic acid to the cyclooxygenase pathway, enhances thromboxane production and, hence, platelet aggregation. Blood samples were collected from 10 asthmatic patients before and 2 weeks after standard Zileuton treatment. Spontaneous platelet aggregation was measured in platelet-rich plasma. Platelet-rich plasma was also used to determine thromboxane B(2), a stable metabolite of thromboxane A(2), as the indirect measure of thromboxane A(2) because thromboxane A(2) is too unstable for assay. Baseline thromboxane B(2) and platelet aggregation values in the 10 asthmatic patients were normal. Treatment with Zileuton for 2 weeks significantly increased thromboxane B(2) levels from baseline levels of 267 +/- 54 microg/l to 389 +/- 62 microg/l after 2 weeks of treatment (P < 0.0002). Spontaneous platelet aggregation also increased significantly from baseline values of 4.2 +/- 2.4% to 6.8 +/- 2.8% after 2 weeks of treatment (P < 0.0001). These results establish that Zileuton, an effective drug for asthma, adversely affects in vitro platelet function. The findings suggest that this drug, and perhaps related agents also, may pose a thrombotic risk; clinical attention will be needed to address this possibility.

Recurrent panniculitis in a man with asthma receiving treatment with leukotriene-modifying agents.

Leukotriene-modifying drugs are novel agents introduced recently to treat asthma. Both 5-lipoxygenase inhibitors, such as zileuton, and leukotriene receptor antagonists, such as zafirlukast and montelukast, have proved effective in the treatment of asthma. To our knowledge, there have been no detailed reports regarding dermatologic manifestations of this class of drugs. This article describes an unusual case of erythema nodosum in a 46-year-old asthmatic man who received 2 different leukotriene modifiers.

5-Lipoxygenase inhibition: a new treatment strategy for Sjögren-Larsson syndrome.

The Sjögren-Larsson syndrome (SLS) is a severe neurocutaneous disorder due to fatty aldehyde dehydrogenase (FALDH) deficiency. The recent discovery of the role of FALDH in the degradation of leukotriene B4 (LTB4) opened the way to the development of a new therapeutic strategy for SLS, i.e. 5-lipoxygenase inhibition. We treated one SLS patient with zileuton during five weeks. During the treatment period we found decreased values of LTB4 and omega-OH-LTB4. The severity of the pruritus diminished, and favorable changes in the child's behavior were observed. The height of the prominent "lipid peak" of cerebral white matter (that is characteristically found on proton magnetic resonance spectroscopy in SLS patients) decreased during treatment, and increased again when treatment was stopped. In conclusion, the beneficial effects of 5-lipoxygenase inhibition in SLS are very promising and encourage further research.