A double-blind, placebo-controlled trial to assess the efficacy of quetiapine fumarate XR in very heavy-drinking alcohol-dependent patients

Background: Despite advances in developing medications to treat alcohol dependence, few such medications have been approved by the Food and Drug Administration. Identified molecular targets are encouraging and can lead to the development and testing of new compounds. Atypical antipsychotic medications have been explored with varying results. Prior research suggests that the antipsychotic quetiapine may be beneficial in an alcohol‐dependent population of very heavy drinkers. Methods: In this double‐blind, placebo‐controlled trial, 224 alcohol‐dependent patients who reported very heavy drinking were recruited across 5 clinical sites. Patients received either quetiapine or placebo and Medical Management behavioral intervention. Patients were stratified on gender, clinical site, and reduction in drinking prior to randomization. Results: No differences between the quetiapine and placebo groups were detected in the primary outcome, percentage heavy‐drinking days, or other drinking outcomes. Quetiapine significantly reduced depressive symptoms and improved sleep but had no effect on other nondrinking outcomes. Results from a subgroup analysis suggest that patients who reduced their drinking prior to randomization had significantly better drinking outcomes during the maintenance phase (p < 0.0001). No significant interactions, however, were observed between reducer status and treatment group. Finally, quetiapine was generally well tolerated. Statistically significant adverse events that were more common with quetiapine versus placebo include dizziness (14 vs. 4%), dry mouth (32 vs. 9%), dyspepsia (13 vs. 2%), increased appetite (11 vs. 1%), sedation (15 vs. 3%), and somnolence (34 vs. 9%). Conclusions: This multisite clinical trial showed no efficacy for quetiapine compared with placebo at reducing alcohol consumption in heavy‐drinking alcohol‐dependent patients.     

Repeated Multimodality Ablative Therapies for Oligorecurrent Pulmonary Metastatic Disease

Stereotactic body radiotherapy (SBRT) and percutaneous thermal ablation (TA) are alternatives to surgery for the management of pulmonary oligometastases. In this collaborative work, we retrospectively analyzed patients who had undergone iterative focal ablative treatments of pulmonary oligometastases. We hypothesized that repeated ablative therapies could benefit patients with consecutive oligometastatic relapses. Patients treated with SBRT and/or TA for pulmonary oligometastases in two French academic centers between October 2011 and November 2016 were included. A total of 102 patients with 198 lesions were included; 45 patients (44.1%) received repeated focal treatments at the pulmonary site for an oligorecurrent disease (the “multiple courses” group). Median follow-up was 22.5 months. The 3-year overall survival rates of patients who had a single treatment sequence (the “single course” group) versus the “multiple courses” were 73.9% and 78.8%, respectively, which was not a statistically significant difference (p = 0.860). The 3-year systemic therapy-free survival tended to be longer in the “multiple courses” group (50.4%) than in the “single course” group (44.7%) (p = 0.081). Tolerance of repeated treatments was excellent with only one grade 4 toxicity. Thereby, multimodality repeated ablative therapy is effective in patients with pulmonary oligorecurrent metastases. This strategy may delay the use of more toxic systemic therapy.     

Effect of the major glycosides of Harpagophytum procumbens (Devil's Claw) on epidermal cyclooxygenase-2 (COX-2) in vitro

Harpagophytum procumbens, commonly known as Devil's Claw, is indigenous to southern Africa, and extracts of the tubers have been used for centuries in the treatment of a variety of inflammatory disorders. Its major active components, harpagoside (1), harpagide (2), 8-coumaroylharpagide (3), and verbascoside (4), are believed to interact either synergistically or antagonistically in modulating the enzymes responsible for inducing inflammation, although this has not been probed hitherto. In the current work, the ability of these compounds to inhibit the expression of COX-2 following administration to freshly excised porcine skin has been investigated. An ethanol-soluble extract of H. procumbens tubers and two of the pure compounds tested showed promising activity in Western blotting and immunocytochemical assays, with harpagoside (1) and 8-coumaroylharpagide (3) exhibiting greater reductions in COX-2 expression than verbascoside (4). Harpagide (2) caused a significant increase in the levels of COX-2 expression after 6 h of topical application. The data suggest that the efficacy of H. procumbens is dependent upon the ratios of compounds 1-4 present, which is inconsistent with some current official monograph specifications based solely on harpagoside (1) content.     

Isradipine, a dihydropyridine-class calcium channel antagonist, attenuates some of d-methamphetamine’s positive subjective effects: a preliminary study

  Rationale: Dopamine (DA) pathways in the midbrain mediate d-methamphetamine’s rewarding effects associated with its abuse liability. Isradipine, a dihydropyridine-class calcium channel antagonist, reduces the rewarding effects of psychostimulants such as cocaine and d-amphetamine, presumably by antagonizing these central DA pathways. This is the first experiment to test the hypothesis that the rewarding effects of d-methamphetamine, like other psychostimulants, can be reduced by isradipine. Objective: We studied the effects of high dose isradipine (0.21 mg/kg orally), on the positive subjective effects associated with the abuse liability of low and high dose d-methamphetamine (0.21 mg/kg and 0.42 mg/kg orally, respectively). Methods: Using a double-blind, double-dummy, placebo-controlled, Latin-Square, cross-over design, 18 healthy male and female volunteers received each of the following six treatments separated by a rest period of 2–7 days: a) placebo+placebo; b) low-dose d-methamphetamine+placebo); c) high-dose d-methamphetamine+placebo; d) high dose isradipine+placebo); e) low-dose d-methamphetamine+high dose isradipine, and f) high-dose d-methamphetamine+high dose isradipine. Results: d-Methamphetamine produced orderly increases in positive subjective measures of both stimulation and mood. Pre-treatment with isradipine significantly reduced some of these positive subjective effects and craving for d-methamphetamine. Conclusion: Isradipine as an anti-reward or craving reducing medication is a promising therapeutic agent for the treatment of d-methamphetamine dependence. Received: 17 November 1998 / Final version: 4 February 1999     

From Drug Screening to Target Deconvolution: a Target-Based Drug Discovery Pipeline Using Leishmania Casein Kinase 1 Isoform 2 To Identify Compounds with Antileishmanial Activity

Existing therapies for leishmaniases present significant limitations, such as toxic side effects, and are rendered inefficient by parasite resistance. It is of utmost importance to develop novel drugs targeting Leishmania that take these two limitations into consideration. We thus chose a target-based approach using an exoprotein kinase, Leishmania casein kinase 1.2 (LmCK1.2) that was recently shown to be essential for intracellular parasite survival and infectivity. We developed a four-step pipeline to identify novel selective antileishmanial compounds. In step 1, we screened 5,018 compounds from kinase-biased libraries with Leishmania and mammalian CK1 in order to identify hit compounds and assess their specificity. For step 2, we selected 88 compounds among those with the lowest 50% inhibitory concentration to test their biological activity on host-free parasites using a resazurin reduction assay and on intramacrophagic amastigotes using a high content phenotypic assay. Only 75 compounds showed antileishmanial activity and were retained for step 3 to evaluate their toxicity against mouse macrophages and human cell lines. The four compounds that displayed a selectivity index above 10 were then assessed for their affinity to LmCK1.2 using a target deconvolution strategy in step 4. Finally, we retained two compounds, PP2 and compound 42, for which LmCK1.2 seems to be the primary target. Using this four-step pipeline, we identify from several thousand molecules, two lead compounds with a selective antileishmanial activity.     

PD-L2 is expressed on activated human T cells and regulates their function

T-cell activation and proliferation are regulated by cosignaling adhesion molecules involved in positive or negative signals. Programmed death (PD)-1 is one of immune inhibitory molecules that is expressed in activated T cells and is a promising target for immunotherapy. Both PD-1 ligands, PD-L1 and PD-L2 are expressed on antigen presenting cells (APCs) involved in the dialogue between a T cell and an APC. Here, we analysed the expression of these ligands, especially for PD-L2, on T cells. PD-L2 appears to be expressed on activated CD4 and CD8T cell subsets. Moreover, as PD-1 molecule, PD-L2 engagement at the surface of T cells is able to down-modulate cytokine production and cell proliferation. These observations indicate that PD-L2 is expressed following activation and is involved in the regulation of T cell function, highlighting the level of complexity in the T cell cosignaling network.     

Comorbid alcohol and nicotine dependence: from the biomolecular basis to clinical consequences

This article represents the proceedings of a symposium presented at the 12th Congress of the International Society for Biomedical Research on Alcoholism held in Heidelberg/Mannheim, Germany, on October 1, 2004. The organizers and cochairs were Nassima Ait‐Daoud, MD, and Gerhard A. Wiesbeck, MD. The presentations included the following: (1) The Role of Nicotinic Acetylcholine Receptors in Alcohol‐Seeking Behavior, by Przemyslaw Bienkowski, MD, PhD; (2) Utilization of Linkage Analysis Combined with Microarray Technology to Identify Genes and Mechanisms Underlying Nicotine and Alcohol Use and Abuse in Humans and Rodents, by Ming D. Li, PhD; (3) Smoking and Alcoholic Chronic Pancreatitis: The Underestimated Risk?, by Roland H. Pfützer, MD; (4) Anticraving Medication in Alcohol and Nicotine Dependence, by Otto M. Lesch, MD, PhD; and (5) Pharmacotherapy for Promotion of Abstinence from Nicotine Among Alcohol‐Dependent Individuals, by Bankole A. Johnson, DSc, MD, PhD.     

TRPC6 channel translocation into phagosomal membrane augments phagosomal function

Defects in the innate immune system in the lung with attendant bacterial infections contribute to lung tissue damage, respiratory insufficiency, and ultimately death in the pathogenesis of cystic fibrosis (CF). Professional phagocytes, including alveolar macrophages (AMs), have specialized pathways that ensure efficient killing of pathogens in phagosomes. Phagosomal acidification facilitates the optimal functioning of degradative enzymes, ultimately contributing to bacterial killing. Generation of low organellar pH is primarily driven by the V-ATPases, proton pumps that use cytoplasmic ATP to load H⁺ into the organelle. Critical to phagosomal acidification are various channels derived from the plasma membrane, including the anion channel cystic fibrosis transmembrane conductance regulator, which shunt the transmembrane potential generated by movement of protons. Here we show that the transient receptor potential canonical-6 (TRPC6) calcium-permeable channel in the AM also functions to shunt the transmembrane potential generated by proton pumping and is capable of restoring microbicidal function to compromised AMs in CF and enhancement of function in non-CF cells. TRPC6 channel activity is enhanced via translocation to the cell surface (and then ultimately to the phagosome during phagocytosis) in response to G-protein signaling activated by the small molecule (R)-roscovitine and its derivatives. These data show that enhancing vesicular insertion of the TRPC6 channel to the plasma membrane may represent a general mechanism for restoring phagosome activity in conditions, where it is lost or impaired.Chronic infection and inflammation in the airways in cystic fibrosis (CF), as well as chronic obstructive pulmonary disease (COPD), tuberculosis, and asthma are now among the most common chronic diseases. Pulmonary infection associated with these diseases has historically been treated with antibiotics that kill bacteria but also select for development of resistance in the pathogen in the chronically infected lung (1, 2). One solution to antimicrobial drug resistance is to target the host rather than the pathogen. This strategy necessitates finding alternative targets or signaling strategies amplifying or restoring bactericidal capacity in the cells charged with the task of resolving chronic infection.Mononuclear phagocytes orchestrate the innate immune response in the lung through the combinatorial interplay between the phagocytic uptake and killing of bacterial invaders, clearance of apoptotic cells, antigen presentation, and secretion of vesicle-bound signaling molecules to recruit help in the resolution of infection. Ionic fluxes across the phagosomal membrane that encloses the pathogen produce a hostile acidic environment developed through the action of a V-ATPase proton translocation. However, a positive intraphagosomal membrane potential generated by proton translocation minimizes the proton content of the phagosome. An influx of Cl⁻ via Cl⁻ channels reduces the membrane potential generated by the proton pump, thereby, allowing maximal acidification of the phagolysosomal compartment, which in turn maximizes the activation of lysosomal degradative enzymes, generation of hypochlorous acid, and consequent bacterial killing (3, 4). We have previously demonstrated that murine alveolar macrophages (AMs) use the anion channel cystic fibrosis transmembrane conductance regulator (CFTR) as a Cl⁻ permeation pathway in the phagosomal membrane. In CF, loss of functional CFTR in the AM alkalinizes the phagosomal lumen and allows antimicrobial-resistant bacterial pathogens to survive macrophage surveillance.Not all tissue macrophages use CFTR as a charge compensation pathway in phagolysosomal acidification (4). In fact, recent data suggest that multiple V-ATPase charge-shunt pathways can exist in diverse macrophage lineages (5) via lysosomal recruitment and membrane insertion upon particle uptake. This observation led us to search for possible alternative charge-shunt pathways in pulmonary macrophages and how they might be activated or targeted to the maturing phagosome. Could a pharmacological tool circumvent the defect in CF AMs and activate alternative pathways to rescue both organellar acidification and bactericidal activity in cells expressing mutations in CFTR? Such a tool might activate parallel charge-shunt pathways used in peritoneal macrophages for maximum acidification, thereby allowing them to clear bacteria independently of CFTR expression as well as amplify the microbicidal response in the presence of functional CFTR. The transport proteins and channels active in peritoneal macrophage bacterial clearance have not been described but may involve a K⁺/H⁺ exchanger important in promoting excitatory synaptic vesicle filling (6) or a cation channel moving positive charge out of the phagolysosomal compartment, as has been suggested for macrophage cell lines (7).We began our investigations pursuing a novel pharmacological strategy to identify compounds that would resolve bacterial infection in the CF lung without the use of antimicrobials. We picked a cellular defect in CF because of the availability of animal models and extended our observations to non-CF human pulmonary cells. We designed screening assays of phagosome function, which could be used in a clinical setting as both diagnostic and investigational tools. We interrogated host function by studying surface receptor-mediated mechanisms that might provide parallel signaling pathways in subcellular organellar function in the resolution of disease.We report that a series of small molecules first identified in chemotherapeutics, (R)-roscovitine [2-(R)-(1-ethyl-2-hydroxyethylamino)-6-benzylamino-9-isopropylpurine] and its derivatives, restore microbicidal function to compromised AMs in CF and enhance function in non-CF cells. The compounds use a G protein-mediated signaling pathway, which results in the mobilization of transient receptor potential canonical-6 (TRPC6) calcium-permeable, nonselective cation channels to the plasma membrane and subsequently to the phagosomal membrane. Members of the TRP channel family have been implicated in a number of critical phagocytic functions, including particle uptake, migration, and reactive oxygen species (ROS) production (5, 8–11). Numerous studies (12–15) have suggested TRP channels as potential targets for the development of therapies in pulmonary inflammation because of their abundant and diverse cellular expression throughout the respiratory tree. Although TRPC6 channels have been previously identified in lung macrophages and shown to be up-regulated in COPD, their precise role in the pathophysiology of the disease is yet to be determined (16). Perhaps more relevant to our study, a TRPC6-mediated Ca²⁺ influx is increased in human CF airway epithelial cells, possibly because of a functional association between CFTR and TRPC6 that is lost in CF (17), with unknown consequences. To our knowledge, this study is the first to associate TRPC6 channels a specific drug-targeting strategy for the resolution chronic pulmonary infection.     

Molecular Heterogeneity of β-Thalassemia in Algeria: How to Face Up to a Major Health Problem

This study concerns the molecular characterization of β-thalassemia (β-thal) alleles in 210 chromosomes. In the studied population, mutations were detected in 98% of the β-thalassemic chromosomes. Twenty-one molecular defects have been found, where the five dominant mutations, IVS-I-110 (G>A), nonsense mutation at codon 39 (C>T), the frameshift codon (FSC) 6 (?A), IVS-I-1 (G>A), and IVS-I-6 (T>C), account for 80% of the independent chromosomes. Among the remaining alleles, 16 different mutations were identified, half of them being described for the first time in Algeria. These include the ?101 (C>T) and the ?90 (C>T) mutations in the distal and proximal promoter elements, respectively, the FSC 8 (?AA), IVS-I-5 (G>T), IVS-I-128 (T>G), FSC 47 (+A), IVS-II-1 (G>A), and the substitution in the polyadenylation signal (poly A) site AATAAA>AATGAA. Haplotype analyses on rare variants were performed. The possible origin of these mutations either by founder effect or by migrations is discussed, and raises the question of an adequate strategy to be used adapted to socio-economical status.