Evaluation of Selective 5-HT2C Agonists in Acute Seizure Models.

The 5-HT releaser/reuptake inhibitor fenfluramine has been recently reported to provide benefit as an adjunctive treatment for Dravet and Lennox-Gastaut syndromes, two types of severe childhood epilepsy. Despite its enhancement of 5-HT function, many effects of fenfluramine have been demonstrated to be dependent on 5-HT2C receptor activation, suggesting that 5-HT2C receptor activation may have an anticonvulsant property. The present study was designed to evaluate fenfluramine and 5-HT agonists of varying 5-HT2C agonist selectivity, the relatively nonselective mCPP and Ro 60-0175, and the selective 5-HT2C agonists lorcaserin and CP-809101 across a variety of acute seizure tests conducted in adult rats and mice, which have been instrumental in identifying the majority of clinically efficacious antiepileptic drugs. Tests included the maximal electroshock seizure (MES), MES threshold, and 6 Hz electrical convulsive seizure models and the chemoconvulsant pentylenetetrazole test. The effect of mCPP, lorcaserin, and CP-809101 against electrically evoked seizures in amygdala kindled rats was also investigated. Overall, at doses known to interact with 5-HT2CR, there was no clear class-related effect of these agonists in any test. The only notable antiseizure effect of fenfluramine was inhibition of MES-induced tonic seizures in the rat. The current preclinical studies using the classical acute seizure tests and an amygdala kindling model do not identify a reliable antiseizure effect of fenfluramine, an agent now used in the treatment of human epilepsies, including Dravet syndrome and Lennox-Gastaut syndrome. Given the nature of these epilepsies, early life and/or genetic models may have better construct validity and be more appropriate for further study.

Reversal effect of Riparin IV in depression and anxiety caused by corticosterone chronic administration in mice.

Mental disorders have a multifactorial etiology and stress presents as one of the causal factors. In depression, it is suggested that high cortisol concentration contributes directly to the pathology of this disease. Based on that, the study aims to evaluate the potential antidepressant effect of Riparin IV (Rip IV) in mice submitted to chronic stress model by repeated corticosterone administration. Female Swiss mice were selected into four groups: control (Ctrl), corticosterone (Cort), Riparin IV (Cort + Rip IV) and fluvoxamine (Cort + Flu). Three groups were administrated subcutaneously (SC) with corticosterone (20 mg/kg) during twenty-one days, while the control group received only vehicle. After the fourteenth day, groups were administrated tested drugs: Riparin IV, fluvoxamine or distilled water, by gavage, 1 h after subcutaneous injections. After the final treatment, animals were exposed to behavioral models such as forced swimming test (FST), tail suspension test (TST), open field test (OFT), elevated plus maze (EPM) and sucrose preference test (SPT). The hippocampus was also removed for the determination of BDNF levels. Corticosterone treatment altered all parameters in behavioral tests, leading to a depressive- and anxious-like behavior. Riparin IV and fluvoxamine exhibit antidepressant effect in FST, TST and SPT. In EPM and OFT, treatment displayed anxiolytic effect without alteration of locomotor activity. Corticosterone administration decreased BDNF levels and Riparin IV could reestablish them, indicating that its antidepressant effect may be related to ability to ameliorate hippocampal neurogenesis. These findings suggest that Riparin IV improves the depressive and anxious symptoms after chronic stress and could be a new alternative treatment for patients with depression.

Therapeutic effects and anti-metastasis effects of cationic liposomes against pancreatic cancer metastasis in vitro and in vivo.

The anti-metastatic effects of cationic liposomes (CL) composed of 87 mol% dimyristoylphosphatidylcholine (DMPC), 8 mol% O,O'-ditetradecanoyl-N-(α-trimethylammonioacetyl) diethanolamine chloride (2C14ECl) and 5 mol% polyoxyethylene(21) dodecyl ether (C12(EO)21) was investigated for human pancreatic cancer (BxPC-3) cells. The inhibitory effect of CL on the migration of BxPC-3 cells was observed based on a wound scratch assay. CL suppressed pseudopodium formation of BxPC-3 cells. The anti-invasive effect of CL against BxPC-3 cells was observed via a Matrigel invasion assay. The anti-invasive effect of CL for BxPC-3 cells was found to occur through the inhibition of MMP2, MMP9, and MMP14. Overall, the results of this study revealed for the first time, the therapeutic effects and anti-metastasis activity of CL in xenograft mouse models for peritoneal metastasis of human pancreatic cancer.

Synthesis and Biological in vitro and in vivo Evaluation of 2-(5-Nitroindazol-1-yl)ethylamines and Related Compounds as Potential Therapeutic Alternatives for Chagas Disease.

Chagas disease, a neglected tropical disease caused by infection with the protozoan parasite Trypanosoma cruzi, is a potentially life-threatening illness that affects 5-8 million people in Latin America, and more than 10 million people worldwide. It is characterized by an acute phase, which is partly resolved by the immune system, but then develops as a chronic disease without an effective treatment. There is an urgent need for new antiprotozoal agents, as the current standard therapeutic options based on benznidazole and nifurtimox are characterized by limited efficacy, toxicity, and frequent failures in treatment. In vitro and in vivo assays were used to identify some new low-cost 5-nitroindazoles as a potential antichagasic therapeutic alternative. Compound 16 (3-benzyloxy-5-nitro-1-vinyl-1H-indazole) showed improved efficiency and lower toxicity than benznidazole in both in vitro and in vivo experiments, and its trypanocidal activity seems to be related to its effect at the mitochondrial level. Therefore, compound 16 is a promising candidate for the development of a new anti-Chagas agent, and further preclinical evaluation should be considered.

Pharmacological interventions for benzodiazepine discontinuation in chronic benzodiazepine users.

BACKGROUND: Prolonged treatment with benzodiazepines is common practice despite clinical recommendations of short-term use. Benzodiazepines are used by approximately 4% of the general population, with increased prevalence in psychiatric populations and the elderly. After long-term use it is often difficult to discontinue benzodiazepines due to psychological and physiological dependence. This review investigated if pharmacological interventions can facilitate benzodiazepine tapering. OBJECTIVES: To assess the benefits and harms of pharmacological interventions to facilitate discontinuation of chronic benzodiazepine use. SEARCH METHODS: We searched the following electronic databases up to October 2017: Cochrane Drugs and Alcohol Group's Specialised Register of Trials, CENTRAL, PubMed, Embase, CINAHL, and ISI Web of Science. We also searched ClinicalTrials.gov, the WHO ICTRP, and ISRCTN registry, and checked the reference lists of included studies for further references to relevant randomised controlled trials. SELECTION CRITERIA: We included randomised controlled trials comparing pharmacological treatment versus placebo or no intervention or versus another pharmacological intervention in adults who had been treated with benzodiazepines for at least two months and/or fulfilled criteria for benzodiazepine dependence (any criteria). DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: We included 38 trials (involving 2543 participants), but we could only extract data from 35 trials with 2295 participants. Many different interventions were studied, and no single intervention was assessed in more than four trials. We extracted data on 18 different comparisons. The risk of bias was high in all trials but one. Trial Sequential Analysis showed imprecision for all comparisons.For benzodiazepine discontinuation, we found a potential benefit of valproate at end of intervention (1 study, 27 participants; risk ratio (RR) 2.55, 95% confidence interval (CI) 1.08 to 6.03; very low-quality evidence) and of tricyclic antidepressants at longest follow-up (1 study, 47 participants; RR 2.20, 95% CI 1.27 to 3.82; low-quality evidence).We found potentially positive effects on benzodiazepine withdrawal symptoms of pregabalin (1 study, 106 participants; mean difference (MD) -3.10 points, 95% CI -3.51 to -2.69; very low-quality evidence), captodiame (1 study, 81 participants; MD -1.00 points, 95% CI -1.13 to -0.87; very low-quality evidence), paroxetine (2 studies, 99 participants; MD -3.57 points, 95% CI -5.34 to -1.80; very low-quality evidence), tricyclic antidepressants (1 study, 38 participants; MD -19.78 points, 95% CI -20.25 to -19.31; very low-quality evidence), and flumazenil (3 studies, 58 participants; standardised mean difference -0.95, 95% CI -1.71 to -0.19; very low-quality evidence) at end of intervention. However, the positive effect of paroxetine on benzodiazepine withdrawal symptoms did not persist until longest follow-up (1 study, 54 participants; MD -0.13 points, 95% CI -4.03 to 3.77; very low-quality evidence).The following pharmacological interventions reduced symptoms of anxiety at end of intervention: carbamazepine (1 study, 36 participants; MD -6.00 points, 95% CI -9.58 to -2.42; very low-quality evidence), pregabalin (1 study, 106 participants; MD -4.80 points, 95% CI -5.28 to -4.32; very low-quality evidence), captodiame (1 study, 81 participants; MD -5.70 points, 95% CI -6.05 to -5.35; very low-quality evidence), paroxetine (2 studies, 99 participants; MD -6.75 points, 95% CI -9.64 to -3.86; very low-quality evidence), and flumazenil (1 study, 18 participants; MD -1.30 points, 95% CI -2.28 to -0.32; very low-quality evidence).Two pharmacological treatments seemed to reduce the proportion of participants that relapsed to benzodiazepine use: valproate (1 study, 27 participants; RR 0.31, 95% CI 0.11 to 0.90; very low-quality evidence) and cyamemazine (1 study, 124 participants; RR 0.33, 95% CI 0.14 to 0.78; very low-quality evidence). Alpidem decreased the proportion of participants with benzodiazepine discontinuation (1 study, 25 participants; RR 0.41, 95% CI 0.17 to 0.99; number needed to treat for an additional harmful outcome (NNTH) 2.3 participants; low-quality evidence) and increased the occurrence of withdrawal syndrome (1 study, 145 participants; RR 4.86, 95% CI 1.12 to 21.14; NNTH 5.9 participants; low-quality evidence). Likewise, magnesium aspartate decreased the proportion of participants discontinuing benzodiazepines (1 study, 144 participants; RR 0.80, 95% CI 0.66 to 0.96; NNTH 5.8; very low-quality evidence).Generally, adverse events were insufficiently reported. Specifically, one of the flumazenil trials was discontinued due to severe panic reactions. AUTHORS' CONCLUSIONS: Given the low or very low quality of the evidence for the reported outcomes, and the small number of trials identified with a limited number of participants for each comparison, it is not possible to draw firm conclusions regarding pharmacological interventions to facilitate benzodiazepine discontinuation in chronic benzodiazepine users. Due to poor reporting, adverse events could not be reliably assessed across trials. More randomised controlled trials are required with less risk of systematic errors ('bias') and of random errors ('play of chance') and better and full reporting of patient-centred and long-term clinical outcomes. Such trials ought to be conducted independently of industry involvement.

Antiviral activity of novel oseltamivir derivatives against some influenza virus strains.

The aim of this study was to investigate the in vitro cytotoxicity of oseltamivir derivatives and determine their activity against A/H1N1/PR/8/34 and A/H3N2/HongKong/8/68 - strains of influenza virus. Antiviral activity of these compounds was determined by using two methods. MTT staining was used to assess the viability of MDCK cells infected with influenza viruses and treated with various concentrations of drugs. In parallel, the effect of drugs on viral replication was assessed using the hemagglutination test. The most toxic compounds were: OS-64, OS-35, OS-29, OS-27 and OS-25, whereas OS-11, OS-20 and OS-23 were the least toxic ones. Statistically significant antiviral effect at a higher virus dose was shown by compounds: OS-11, OS-20, OS-27, OS-35, and OS-64. H3N2 virus was sensitive to 10-times lower concentrations of OS-11 and OS-35 than H1N1. At a lower infection dose, the antiviral activity was observed for OS-11, OS 27, OS-35 and OS-20. OS-64 turned out to be effective only at a high concentration. OS-23 showed no antiviral effect.

Effect of ring-constrained phenylpropyloxyethylamines on sigma receptors.

A series of ring-constrained phenylpropyloxyethylamines, partial opioid structure analogs and derivatives of a previously studied sigma (σ) receptor ligand, was synthesized and evaluated at σ and opioid receptors for receptor selectivity. The results of this study identified several compounds with nanomolar affinity at both σ receptor subtypes. Compounds 6 and 9 had the highest selectivity for both σ receptor subtypes, compared to µ opioid receptors. In addition, compounds 6 and 9 significantly reduced the convulsive effects of cocaine in mice, which would be consistent with antagonism of σ receptors.

Structure guided P1' modifications of HEA derived ß-secretase inhibitors for the treatment of Alzheimer's disease.

The synthesis and SAR of a series of BACE-1 hydroxyethyl amine inhibitors containing substitutions on a spirocyclobutyl moiety is described. Selectivity against cathepsin D, a related aspartyl protease with potential off target toxicity, and improved microsomal stability is exemplified.

An ex vivo, assessor blind, randomised, parallel group, comparative efficacy trial of the ovicidal activity of three pediculicides after a single application--melaleuca oil and lavender oil, eucalyptus oil and lemon tea tree oil, and a "suffocation" pediculicide.

BACKGROUND: There are two components to the clinical efficacy of pediculicides: (i) efficacy against the crawling-stages (lousicidal efficacy); and (ii) efficacy against the eggs (ovicidal efficacy). Lousicidal efficacy and ovicidal efficacy are confounded in clinical trials. Here we report on a trial that was specially designed to rank the clinical ovicidal efficacy of pediculicides. Eggs were collected, pre-treatment and post-treatment, from subjects with different types of hair, different coloured hair and hair of different length. METHOD: Subjects with at least 20 live eggs of Pediculus capitis (head lice) were randomised to one of three treatment-groups: a melaleuca oil (commonly called tea tree oil) and lavender oil pediculicide (TTO/LO); a eucalyptus oil and lemon tea tree oil pediculicide (EO/LTTO); or a "suffocation" pediculicide. Pre-treatment: 10 to 22 live eggs were taken from the head by cutting the single hair with the live egg attached, before the treatment (total of 1,062 eggs). TREATMENT: The subjects then received a single treatment of one of the three pediculicides, according to the manufacturers' instructions. Post-treatment: 10 to 41 treated live eggs were taken from the head by cutting the single hair with the egg attached (total of 1,183 eggs). Eggs were incubated for 14 days. The proportion of eggs that had hatched after 14 days in the pre-treatment group was compared with the proportion of eggs that hatched in the post-treatment group. The primary outcome measure was % ovicidal efficacy for each of the three pediculicides. RESULTS: 722 subjects were examined for the presence of eggs of head lice. 92 of these subjects were recruited and randomly assigned to: the "suffocation" pediculicide (n = 31); the melaleuca oil and lavender oil pediculicide (n = 31); and the eucalyptus oil and lemon tea tree oil pediculicide (n = 30 subjects). The group treated with eucalyptus oil and lemon tea tree oil had an ovicidal efficacy of 3.3% (SD 16%) whereas the group treated with melaleuca oil and lavender oil had an ovicidal efficacy of 44.4% (SD 23%) and the group treated with the "suffocation" pediculicide had an ovicidal efficacy of 68.3% (SD 38%). CONCLUSION: Ovicidal efficacy varied substantially among treatments, from 3.3% to 68.3%. The "suffocation" pediculicide and the melaleuca oil and lavender oil pediculicide (TTO/LO) were significantly more ovicidal than eucalyptus oil and lemon tea tree oil pediculicide (EO/LTTO) (P < 0.0001). Ranking: 1. "Suffocation" pediculicide (68.3% efficacy against eggs); 2. Melaleuca oil and lavender oil (44.4%) pediculicide; 3. Eucalyptus oil and lemon tea tree oil (3.3%) pediculicide. The "suffocation" pediculicide and TTO/LO are also highly efficacious against the crawling-stages. Thus, the "suffocation" pediculicide and TTO/LO should be recommended as first line treatments.

Effects of the 5-HT(6) receptor agonist ST 1936 on depression- and anhedonia-like experimental models.

Serotonin 5-HT(6) receptor agonists and antagonists have been proposed as possible useful compounds in the treatment of psychiatric disorders such as depression. This study was aimed at characterizing ST 1936, a new 5-HT(6) receptor agonist, as a possible antidepressant/anti-anhedonic drug by studying its effects on three experimental models of depression. These models are based on the behavioral sequelae induced in rats by unavoidable stressors that result in decreased reactivity to avoidable stressors (escape deficit, ED) and an anhedonia-like condition based on the disruptive effect of stress on the competence to acquire an instrumental vanilla sugar-sustained appetitive behavior (VAB). The repeated administration of ST 1936 prevented the development of ED, but did not revert a condition of chronic ED. The protective effect of ST 1936 was antagonized by co-administration of SB 271046, a 5-HT(6) receptor antagonist, indicating that the 5-HT(6) receptor stimulation is crucial for triggering a plasticity process that resulted in the prevention of ED development. ST 1936 administration in rats undergoing VAB training did not interfere with its acquisition, whereas SB 271046 administered in similar conditions prevented VAB acquisition. Moreover, ST 1936 administration in rats trained in the Y-maze while exposed to a chronic stress protocol consistently antagonized the stress-disrupting effect, and also this effect was antagonized by SB 271046 coadministration. It was concluded that a tonic 5-HT(6) receptor activity was crucial for VAB acquisition, and that pharmacological stimulation of 5-HT(6) receptors reinstated a stress-reduced hedonic competence with an efficacy similar to that of classical antidepressant drugs.

Impulsive action induced by amphetamine, cocaine and MK801 is reduced by 5-HT(2C) receptor stimulation and 5-HT(2A) receptor blockade.

Previous work has shown that 5-HT(2C) receptor agonists and 5-HT(2A) receptor antagonists reduce impulsive action, as well as the locomotor stimulant effect of psychomotor stimulants. Since psychomotor stimulants also increase impulsive action we examined the effects of the 5-HT(2C) receptor agonist Ro60-0175, and the 5-HT(2A) receptor antagonist M100907 on impulsive action induced by amphetamine, cocaine and the NMDA receptor antagonist MK801 (dizocilpine). Impulsive action was measured in adult male Long-Evans rats as premature responding in the 5-choice serial reaction time (5-CSRT) test. Initially, we determined that amphetamine (0.3 mg/kg), cocaine (15 mg/kg) and MK801 (0.03 mg/kg) induced comparable premature response rates of approximately 50-70 per session, compared to 10-15 responses under baseline conditions. Each drug and its vehicle were then tested in combination with Ro60-0175 (0.1 and 0.6 mg/kg) or its vehicle, or M100907 (0.5 mg/kg) or its vehicle. At 0.1 mg/kg Ro60-0175 did not modify the effects of amphetamine, cocaine or MK801. In contrast, the 0.6 mg/kg dose reduced premature responses induced by amphetamine, cocaine and MK801. M100907 also reduced premature responding induced by all three of these drugs. In general, treatment with Ro60-0175 or M100907 by itself did not consistently alter any of the other aspects of task performance in the 5-CSRT test including number of trials completed, and accuracy of responding. These data show that activation of 5-HT(2C) receptors and blockade of 5-HT(2A) receptors have seemingly similar functional effects on a measure of impulsive action.

BACE-1 hydroxyethylamine inhibitors using novel edge-to-face interaction with Arg-296.

Inhibition of the aspartyl protease BACE-1 has the potential to deliver a disease-modifying therapy for Alzheimer's disease. Herein, is described a series of potent inhibitors based on an hydroxyethylamine (HEA) transition state mimetic template. These inhibitors interact with the non prime side of the enzyme using a novel edge-to-face interaction with Arg-296.

A plant-derived glucocorticoid receptor modulator attenuates inflammation without provoking ligand-induced resistance.

BACKGROUND: Acquired resistance to glucocorticoids constitutes a major clinical challenge, often overlooked in the search for improved alternatives to classic steroids. We sought to unravel how two glucocorticoid receptor-activating compounds, dexamethasone and Compound A, influence glucocorticoid receptor levels and how this can be correlated to their gene regulatory potential. METHODS: Compound A and dexamethasone were applied in a short-term and long-term treatment protocol. By quantitative PCR analysis in fibroblast-like synoviocytes (FLS) the gene regulatory potential of both compounds in the two experimental conditions was analysed. A parallel Western blot assay revealed the glucocorticoid receptor protein levels in both conditions (ex vivo). In addition, this study examined the effect of systemic administration of dexamethasone and Compound A, in concentrations effective to inhibit collagen-induced arthritis, in DBA/1 mice on glucocorticoid receptor levels (in vivo). RESULTS: Compound A does not induce a homologous downregulation of glucocorticoid receptor in vivo and ex vivo, thereby retaining its anti-inflammatory effects after prolonged treatment in FLS. This is in sharp contrast to dexamethasone, showing a direct link between prolonged dexamethasone treatment, decreasing glucocorticoid receptor levels, and the abolishment of inflammatory gene repression in FLS. It was also observed that the acquired low receptor levels after prolonged dexamethasone treatment are still sufficient to sustain the transactivation of endogenous glucocorticoid-responsive element-driven genes in FLS, a mechanism partly held accountable for the metabolic side-effects. CONCLUSION: Compound A is less likely to evoke therapy resistance, as it does not lead to homologous glucocorticoid receptor downregulation, which is in contrast to classic glucocorticoids.

Novel N-(3-carboxyl-9-benzyl-beta-carboline-1-yl)ethylamino acids: synthesis, anti-tumor evaluation, intercalating determination, 3D QSAR analysis and docking investigation.

Sixteen novel N-(3-carboxyl-9-benzyl-beta-carboline-1-yl)ethylamino acids (6a-p) were synthesized as intercalating lead compounds. In the in vitro cytotoxic assay their IC(50) values against five human carcinoma cell lines ranged from 10.95 microM to about 400 microM. On S180 mouse model eight of them exhibited anti-tumor action, four of them showed the same anti-tumor potency as that of cytarabine. The preliminary toxicity evaluation revealed that the LD(50) values of 6a-p should be more than 500 mg/kg. With CT DNA as model system an intercalating mechanism was explored. Using 3D QSAR analysis the relationship of the in vivo anti-tumor activity and the structure was quantitatively described. By docking 6a-p onto d(CGATCG)(2) oligonucleotides the intercalation was demonstrated.

Investigation of the photostability properties of memoquin, a quinone derivative for the treatment of Alzheimer's disease.

The photostability properties of memoquin, a multifunctional compound in preclinical development for the treatment of Alzheimer's disease (AD) were investigated in solutions exposed to radiations, using a xenon arc lamp to simulate the natural sunlight. Reversed phase liquid chromatography coupled with diode array detection and electrospray ionization mass spectrometry (LC-UV/DAD-ESI-MS/MS) was applied to follow the photodegradation and disappearance of memoquin after irradiation. Under optimized chromatographic conditions, memoquin was separated with high resolution from the photoproducts formed in the photoexposed solutions. The results showed that memoquin is more stable at physiological and acid pHs, while it has a slow degradation pattern at more drastic conditions such as basic pH (t(1/2)=389 min) and in methanolic solutions (t(1/2)=465 min). In the irradiated solutions the appearance of photoproducts with lower retention times and molecular weight than memoquin was observed, thus indicating that some fragments were lost from its structure. The photodegradation products were characterized by LC-ESI-MS/MS and LC-UV/DAD analysis. The photoreactive centers were found on the amino groups of the side chains while the 1,4-benzoquinone functionality was maintained. Conversely, memoquin was found to be stable in the dark. These results suggest that, with appropriate handling and storage, memoquin's activity is not impaired.

MTDL design strategy in the context of Alzheimer's disease: from lipocrine to memoquin and beyond.

The multifunctional nature of Alzheimer's disease (AD) provides the logical foundation for the development of an innovative drug design strategy centered on multi-target-directed-ligands (MTDLs). In recent years, the MTDL concept has been exploited to design different ligands hitting different biological targets. Our first rationally designed MTDL was the polyamine caproctamine (1), which provided a synergistic cholinergic action against AD by antagonizing muscarinic M(2) autoreceptors and inhibiting acetylcholinesterase (AChE). Lipocrine (7) represented the next step in our research. Due to its ability to inhibit AChE catalytic and non-catalytic functions together with oxidative stress, 7 emerged as an interesting pharmacological tool for investigating the neurodegenerative mechanism underlying AD. Memoquin (9) is a quinone-bearing polyamine endowed with a unique multifunctional profile. With its development, we arrived at the proof of concept of the MTDL drug discovery approach. Experiments in vitro and in vivo confirmed its multimodal mechanisms of action and its interaction with different end-points of the neurotoxic cascade leading to AD. More recently, the MTDL approach led to carbacrine (12). In addition to the multiple activities displayed by 7, 12 displayed an interesting modulation of NMDA receptor activity. The pivotal role played by this target in AD pathogenesis suggests that 12 may be a promising new chemical entity in the MTDL gold rush.

Memoquin: a multi-target-directed ligand as an innovative therapeutic opportunity for Alzheimer's disease.

Alzheimer's disease is currently thought to be a complex, multifactorial syndrome, unlikely to arise from a single causal factor; instead, a number of related biological alterations are thought to contribute to its pathogenesis. This may explain why the currently available drugs, developed according to the classic drug discovery paradigm of "one-molecule-one-target," have turned out to be palliative. In light of this, drug combinations that can act at different levels of the neurotoxic cascade offer new avenues toward curing Alzheimer's and other neurodegenerative diseases. In parallel, a new strategy is emerging-that of developing a single chemical entity able to modulate multiple targets simultaneously. This has led to a new paradigm in medicinal chemistry, the "multi-target-directed ligand" design strategy, which has already been successfully exploited at both academic and industrial levels. As a case study, we report here on memoquin, a new molecule developed following this strategy. The in vitro and in vivo biological profile of memoquin demonstrates the suitability of the new strategy for obtaining innovative drug candidates for the treatment of neurodegenerative diseases.

Structure-activity relationships of the cycloalkanol ethylamine scaffold: discovery of selective norepinephrine reuptake inhibitors.

Further exploration of the cycloalkanol ethylamine scaffold, of which venlafaxine ( 1) is a member, was undertaken to develop novel and selective norepinephrine reuptake inhibitors (NRIs) for evaluation in a variety of predictive animal models. These efforts led to the discovery of a piperazine-containing analogue, 17g (WY-46824), that exhibited potent norepinephrine reuptake inhibition, excellent selectivity over the serotonin transporter, but no selectivity over the dopamine transporter. Synthesis and testing of a series of cyclohexanol ethylpiperazines identified ( S)-(-)- 17i (WAY-256805), a potent norepinephrine reuptake inhibitor (IC 50 = 82 nM, K i = 50 nM) that exhibited excellent selectivity over both the serotonin and dopamine transporters and was efficacious in animal models of depression, pain, and thermoregulatory dysfunction.

Synthesis and antihyperglycemic activity of novel N-acyl-2-arylethylamines and N-acyl-3-coumarylamines.

A series of novel N-acyl-2-arylethylamines and N-acyl-3-coumarylamines were synthesized and evaluated for their antihyperglycemic activity. Compounds 3g and 6d exhibited lowering of postprandial plasma glucose by 30.7%, 23.3% in SLM and 25.6%, 25.4% in STZ models respectively which is significant compared to metformin and glybenclamide. Other compounds exhibited moderate to good activity ranging from 19.5% to 32.8% in SLM and 3.26% to 25.4% in STZ models.