A new series of pyridazinone-based thioderivatives and pyridazine analogs was synthesized and tested for their ability to bind to the three human formyl peptide receptor (FPR) isoforms (FPR1, FPR2, and FPR3) and to activate intracellular calcium mobilization and chemotaxis in human neutrophils. Among the pyridazin-3(2H)-one derivatives tested, analogs 8b and 8c were mixed FPR1/FPR2 agonists, with median effective concentration values in the micromolar range, and were able to activate chemotaxis and Ca²⁺ flux in human neutrophils in the low micromolar range. Molecular docking studies showed that interaction of a ligand with Arg205 of FPR1 is important for FPR1 agonist activity. For FPR2, differences in activity between oxygen-containing compounds and their thio-analogs were due to steric bulkiness of sulfur-containing groups.

The Aurora family of serine/threonine kinases plays important roles in process of cell division or mitosis. Overexpression of Aurora A, B, and C has been identified in many human cancers including colon carcinoma cells. To date, a number of small molecular inhibitors have been developed for reducing Aurora kinases activities of tumor cells in preclinical and clinical trials. In this study, we describe the properties of AM-005, a novel and orally active Aurora A/B kinase inhibitor. AM-005 irreversibly inhibited the proliferation and levels of phospho-Histone H3 in human colon carcinoma cell lines. Defective mitosis was also visualized in AM-005-treated HT29 cells by microscopy. Flow cytometric analysis showed that AM-005 induced the accumulation of HT29 cells with >4N DNA content in a time or concentration-dependent manner, and HT29 cells underwent severe apoptosis at 72 h. Moreover, AM-005 given intragastrically led to suppression of the proliferative response in the xenograft model of colon carcinoma. These results indicate the utility of AM-005 as a promising noncytotoxic agent for treating human colon carcinoma.

The aim of the present study was to evaluate the antinociceptive activity of the main metamizol (MET) metabolites, 4-methylaminoantipyrine (MAA), 4-aminoantipyrine (AA), 4-formylaminoantipyrine (FAA), and 4-acetylaminoantipyrine (AAA) using the “pain-induced functional impairment in rat” model (PIFIR model). The antinociceptive efficacies of MAA and AA were 288.3% h and 281.1% h, respectively, close to the efficacy of MET (333.80% h). The effective dose to attain 50% of the maximum response (ED₅₀) values for MET, MAA and AA were 126.1, 124.9, and 110.7 mg/kg, respectively. FAA and AAA were essentially inactive in this experimental model. Part of the antinociceptive effect showed by MET in this study might be attributed to the effect of the metabolites MAA and AA on cyclooxygenases COX-1 and COX-2 activity.

The penta-ethyl ester of diethylenetriamine pentaacetic acid (DTPA), a DTPA prodrug designated as C2E5 intended for transdermal delivery for radionuclide decorporation, was first screened with a prototype cream formulation and a hydrocarbon base ointment with C2E5 concentration ranging from 1% to 20%. C2E5 experienced rapid degradation in the cream matrix and C2E5 ointment formulation underwent phase separation due to components incompatibility. Nonaqueous gel matrix comprised of ethyl cellulose/Miglyol 840^® was utilized to formulate C2E5 at different ethyl cellulose and C2E5 content levels. Differential scanning calorimetry (DSC) and scanning electron microscope (SEM) imaging were applied for analysis of the prepared C2E5 gel formulation. C2E5 was stabilized in the nonaqueous gel matrix and ethyl cellulose solubilization by dispersion media was confirmed by DSC and SEM results. Selected C2E5 nonaqueous gel formulations were evaluated in a rodent ²⁴¹Am wound contamination model at a dose level of 200 mg C2E5/kg. The enhanced decorporation over no treatment control on total decorporation, decorporation by urine, and decorporation by feces was 142%, 181%, and 86%, respectively. The nonaqueous gel matrix composed of ethyl cellulose/Miglyol 840 was successfully employed to stabilize the hydrolysis prone C2E5. C2E5 was delivered transdermally and achieved enhanced decorporation for the proof of hypothesis.

The purpose of this study was to evaluate the antinociceptive interaction between acetaminophen and lysine clonixinate in the formalin test, and the possible role of opioidergic and nitric oxide pathways in the interaction. The effect of individual drugs and their combination was evaluated using the 3% formalin test in mice. Acetaminophen (31.6, 100, 178, and 316 mg/kg, i.p.) or lysine clonixinate (5.6, 10, 17.8, and 31.6 mg/kg, i.p.) were administered 10 min before formalin injection. To assess the possible mechanism(s) of action for the combination, naloxone (1 mg/kg) and N (G)-nitro-L-arginine methyl ester (L-NAME) (3 mg/kg) were used. Isobolographic analysis and the interaction index showed a synergistic effect. The experimental ED₃₀ was lower when compared with theoretical ED₃₀. Naloxone, but not L-NAME, reduced the antinociceptive effect of the combination. Administration of antagonists alone did not modify formalin-induced nociception. These data suggest that the acetaminophen–lysine clonixinate combination produces a synergistic effect involving opioid receptors.

Danoprevir is a macrocyclic hepatitis C virus protease inhibitor in clinical development in combination with ritonavir. This study investigated whether ritonavir-boosted danoprevir (DNVr) affects cardiac repolarization, as measured by study-specific corrected QT (QTcS) interval. This was a single-center, single-dose, randomized, double-blind, double-dummy, four-way crossover study. Healthy subjects received a single dose of each treatment (therapeutic-dose DNVr 100/100 mg; supratherapeutic-dose DNVr 400/100 mg; positive control [moxifloxacin 400 mg]; placebo) by randomized sequence, at least 7 days apart. Triplicate readings by continuous Holter 12-lead digital electrocardiogram (Mortara Instruments, Inc., Milwaukee, WI) were obtained during day 1 and 24 h postdose. There was no clinically relevant increase in QTcS interval with DNVr compared with placebo in 52 subjects. The upper one-sided 95% confidence interval for placebo-subtracted change from baseline QTcS was <10 ms at all time points for both DNVr doses. Pronounced increase in QTcS with moxifloxacin treatment confirmed the ECG assay sensitivity. There was no trend for a concentration-dependent effect of danoprevir on QTcS. DNVr doses were well tolerated. This thorough QTc study demonstrates no clinically or statistically significant effect on cardiac repolarization with administration of a single dose of danoprevir (up to 400 mg) with low-dose ritonavir (100 mg) in healthy subjects.

As part of a research program to identify compounds with potent antihypertensive properties, a new series of dihydropyridazin-3(2H)-one analogs was synthesized and evaluated for vasodilator activity in rat thoracic aortic rings. Most of the newly synthesized compounds displayed good vasorelaxant activity as compared with SK&F-93741 and hydralazine, with the N2-unsubstituted 4-isobutyramidophenylpyridazinone derivative 5 being the most potent vasorelaxant, producing vasorelaxation greater than that of hydralazine and equipotent to SK&F-93741. A significant effect of the 6-phenyl substituents and substitution at N-2 position of pyridazinone nucleus on the vasodilatory activity was observed.

Virtual screening is the computational mirror image of high-throughput screening and refers to the in silico evaluation of the biological activity of different molecular entities. Various virtual screening strategies and workflows have been adopted to enhance the process of identification of potential hits. Structure-based scoring relies solely on the interactions between the ligand and the target protein. Conversely, pharmacophore-based scoring relies on the shape complementation of each ligand candidate to a three-dimensional reference ligand. Herewith, we report a systematic integrated hybrid approach, along with the use of well-defined physicochemical and biological filters, to enhance high-ranking hit structures complementing the binding site architecture while also mimicking the three-dimensional features of known active ligands.

With a lack of experimental data on the South African HIV protease enzyme (C-SA HIV PR), very limited research has been conducted to design inhibitors against this enzyme variant. In this paper, a focused integrated structure- and pharmacophore-based virtual screening protocol is introduced to identify potential leads to assist toward designing potent inhibitors against the C-SA PR variant. This rapid and systematic approach can potentially be implemented for the design and discovery of inhibitors against a wide range of biological targets.

In the development of cardiovascular diseases, vascular smooth muscle cells (VSMCs) undergo transition from a contractile to a synthetic phenotype. Notch- and Wnt-dependent signaling pathways play a critical role during this process. Curcumin has potential for clinical use including anti-inflammatory and antitumor actions. However, the effect of curcumin on VSMC phenotype transition remains unclear. In VSMCs isolated from the thoracic aorta of Sprague Dawley rats, curcumin (5–20 μM) produced a concentration-dependent inhibition of serum-elicited VSMC migration. Furthermore, curcumin, at the dose of 20 μM, partially reversed the repression of VSMC markers induced by serum stimulation, an effect associated with attenuation of Jagged-1 and Notch-1 levels and downregulation of the downstream gene Hey-1. Downregulation of Wnt-4 was also observed after curcumin treatment in the presence of serum, which was followed by inhibition of nuclear β-catenin translocation and cyclin D1 expression. These data suggest that curcumin is a potent regulator of VSMCs phenotype transition and may play a critical role in regulating these events after vascular injury.

TRIM, a selective neuronal NOS inhibitor, had anxiolytic effects in the elevated plus-maze (EPM) test. The aim of the present study was to evaluate the involvement of serotonergic system in the anxiolytic-like effect of TRIM in the EPM test, a widely used animal model of anxiety. The anxiolytic-like effect of TRIM (50 mg/kg, i.p.) in adult Wistar albino male rats in the EPM test was antagonized by pretreatment with the 5-HT depleting agent; parachlorophenylalanine methyl ester (3 × 150 mg/kg i.p.) that inhibits 5-HT synthesis; methiothepin (0.1 mg/kg, i.p.), a nonselective 5-HT receptor antagonist; WAY 100635 (0.1 mg/kg i.p.), a selective 5-HT_1A receptor antagonist; GR 127935 (3 mg/kg i.p.), a selective 5-HT_1B/1D receptor antagonist; cyproheptadine (3 mg/kg i.p.), a 5-HT₂ receptor antagonist; or ketanserin (5 mg/kg i.p.), a 5-HT_2A/2C receptor antagonist. The anxiolytic-like effects of TRIM thus appear to be mediated in part by 5-HT₁ and 5-HT₂ receptors.

Nonalcoholic fatty liver disease (NAFLD) is a common aspect of metabolic syndrome, which includes a wide spectrum of liver damage and is closely associated with insulin resistance and lipid peroxidation. The current study aimed to evaluate the protective effect of Ilexgenin A (IA), obtained from Ilex hainanensis Merr., on NAFLD and investigate the underlying mechanisms. Sprague-Dawley rats were fed a high-fat (HF) diet for 3 weeks to induce NAFLD. They were divided into HF diet rats and HF-IA-treated rats, which were treated with IA (80 mg/kg p.o.) for 2 weeks. IA alleviated hepatic steatosis and insulin resistance and reduced plasma levels of alanine transaminase, aspartate aminotransferase, triglyceride, total cholesterol, low-density lipoprotein-cholesterol, malondialdehyde, interleukin 6, and tumor necrosis factor-α, while increasing plasma levels of high-density lipoprotein-cholesterol and superoxide dismutase (SOD). IA decreased hepatic triglycerides, total cholesterol, malondialdehyde, and restored the abnormal down-regulation of SOD. IA also decreased Cytochrome P450 2E1 expression and up-regulated peroxisome proliferator-activated receptor α (PPARα) expression in liver. These results suggested that IA had the potential to attenuate NAFLD by improving lipid metabolism, insulin resistance, inflammation, and oxidative stress, as well as adjusting the expression of Cytochrome P450 2E1 and PPARα.

The antileishmanial activity of compounds inspired by naphthoquinone secondary metabolites from Bignoniaceae is presented. Three structural series of compounds from a common biosynthetic pathway were evaluated against Leishmania major. Compound (15), an analog of the natural product pinnatal, was more active than amphotericin B against L. major. When tested against L. (Viannia) braziliensis and L. infantum, compound 15 showed similar activity to amphotericin B.

The occurrence of convulsions in nonclinical safety studies during development of a new drug often complicates further development of the compound. Based on experiences with a previous development project at H. Lundbeck A/S, where convulsions were noted in animals, a structured approach to investigate possible mechanisms behind the convulsions is suggested. Because it is typically difficult to determine the exact reason for convulsions, it is important to focus on the assessment of possible human risk rather than finding the exact mechanism behind the convulsions. The suggested investigations include the following: calculation of safety margin and assessment of human risk, evaluation of data already captured in performed studies such as clinical chemistry data, description of clinical signs, batches of compound used, expert advice on activities that could enable further development of the compound, investigation of extended in vitro receptor profiles of parent compound and major metabolites, extended histopathology on brain sections, seizure threshold tests of parent compound and major metabolites (in vivo/in vitro), evaluation of electroencephalograms, and finally contact with authorities to discuss a plan for continued clinical development.

A new series of 5-aryl and 5-arylethenylisoxazole carboxylate derivatives was synthesized and evaluated for in vitro activity against Mycobacterium tuberculosis H₃₇R_v. Several compounds exhibited minimum inhibitory concentrations in the low micromolar range (2.3–11.4 μM). A variety of substituents introduced around the isoxazole ring allowed the delineation of preliminary SARs for this new series of compounds.

The basic hemodynamic, electrophysiological, and pharmacological effects of EGIS-7229 (E-7229) were evaluated and compared with those of a pure “Class III“ antiarrhythmic drug (GLG-V-13) in conscious rabbits. Both compounds decreased heart rate dose-dependently. Mean arterial blood pressure was not influenced by E-7229; however, GLG-V-13 produced a significant elevation on this parameter. Left ventricular end-diastolic pressure was gradually increased by E-7229, while GLG-V-13 induced more considerable elevation on that at intermediate doses. QT and QT_cb were lengthened by both compounds; however, higher doses of E-7229 resulted in shortening of the prolonged QT and QT_cb. Ventricular effective refractory period (VERP) was significantly prolonged by either drug studied. Threshold doses to produce QT_50%, QT_max, VERP_50%, and VERP_max were significantly higher for E-7229 compared with GLG-V-13. Significantly higher doses were required for E-7229 to induce arrhythmias. The safety ratio was comparable for both of the compounds. E-7229 can exert multiple actions on cardiac ion channels with minimal influence on hemodynamic parameters and reduced proarrhytmic profile in our preclinical model.

Glucagon-like peptide-1 (GLP-1) is an attractive lead for antidiabetic drug development but its utility is limited due to poor in vivo stability. In this study, we developed a C-terminal site-specific PEGylated analog of GLP-1 based on the structure-activity relationship of GLP-1. Using three steps of chromatography, we obtained the conjugate with a high purity. Polyethylene glycol (PEG) conjugation greatly enhanced GLP-1 potency in vivo without changing its original conformation. In streptozotosin diabetic mice, this conjugate had an improved antidiabetic effect, as measured by fasting glucose/insulin/glycosylated serum protein, oral glucose tolerance test, and histochemical studies. Additionally, this PEG-conjugated peptide delayed gastric emptying without significant effects on body weight gain. Our data indicate that this conjugate may be a promising lead for the development of antidiabetic drugs.

In the present study, we investigated the antiarrhythmic potential of the multichannel blocker CPUY11018 (CY18) in rat cardiac hypertrophy, induced using 7-day treatment with isoproterenol (ISO) (2.5 mg/kg day, s.c.). Arrhythmias were produced using a coronary ligation-reperfusion procedure. CY18 (3 and 10 mg/kg per day, i.p.) and valsartan (10 mg/kg per day, p.o.) were administrated on days 4–7 of ISO treatment. Heart weight index, hemodynamic parameters, electrocardiogram (ECG II) parameters, and arrhythmic scores were monitored and recorded. We examined the ability of CY18 to block the IKr channel under conditions of acidosis and excess reactive oxygen species production in CHO cells expressing the hERG. CY18 had strong antiarrhythmic effects, potentially due to multichannel inhibition. The protective role of CY18 against ISO-induced myocardial hypertrophy was further confirmed using ECG. Incidences of ventricular tachycardia and ventricular fibrillation, heart weight/body weight ratios, and arrhythmic scores were higher in the model group and were suppressed with CY18 treatment. Under simulated pathological conditions, the inhibitory effect of CY18 was impaired in cells treated with 30 μM H₂O₂, which was more effective than acidosis in attenuating CY18-induced inhibition of hERG channel activity.

The present study was undertaken to investigate whether chronic agomelatine treatment which acts as an agonist of melatonergic MT₁ and MT₂ receptors would block unpredictable chronic mild stress (UCMS)-induced depression-like behavior in mice as compared with fluoxetine and melatonin. Male inbred BALB/c mice were treated with agomelatine (10 mg/kg i.p.), melatonin (10 mg/kg ip), fluoxetine (15 mg/kg ip), or vehicle for 5 weeks. All compounds tested blocked the stress-induced deficit in coat state during the UCMS procedure, increased total latency of grooming in the splash test, decreased attack frequency in the resident/intruder test, and reduced immobility time in the tail suspension and forced swimming tests. All compounds also reduced the levels of plasma adrenocorticotropic hormone, interleukin 6, and tumor necrosis factor-alpha in stressed mice. The results of this study indicate that agomelatine, which has a novel mode of action, can be as effective as fluoxetine for the treatment of depression.

Lymphatic filariasis is a disfiguring disease caused by parasitic worms that destroy the human lymphatic system leading to substantial morbidity. The current drug of choice for the treatment of filariasis is diethylcarbamazine and ivermectin with albendazole which are only effective against the microfilaria, leaving the adult worm unaffected, requiring the development of “adulticidal drugs.” Thirty amino substituted 2-hydroxy/5-hydroxy/2-methyl-1,4-naphthoquinones were synthesized via the reaction of 2-hydroxy/5-hydroxy/2-methyl-1,4-naphthoquinones with different primary and secondary amines. Compounds 1–30 were evaluated for in vitro antifilarial activity against the adult bovine filarial worm Setaria digitata as assessed by worm motility and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) reduction assays. The mutagenecity, tumerogenecity, irritantancy, reproductive toxicity, drug score, druglike, and cLogP properties were calculated using OSIRIS property predictor. Ten compounds showed macrofilaricidal activity with ED₅₀ values ranging between 0.086 and 7.6 μM. Taking into account the biological effects and the promising drug-like profiles of these compounds, these represent valid leads for the development of antifilarial agents against adult filarial worm.