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1.
Clin Cancer Res ; 28(13): 2854-2864, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35522533

RESUMEN

PURPOSE: We designed a comprehensive multiple myeloma targeted sequencing panel to identify common genomic abnormalities in a single assay and validated it against known standards. EXPERIMENTAL DESIGN: The panel comprised 228 genes/exons for mutations, 6 regions for translocations, and 56 regions for copy number abnormalities (CNA). Toward panel validation, targeted sequencing was conducted on 233 patient samples and further validated using clinical FISH (translocations), multiplex ligation probe analysis (MLPA; CNAs), whole-genome sequencing (WGS; CNAs, mutations, translocations), or droplet digital PCR (ddPCR) of known standards (mutations). RESULTS: Canonical immunoglobulin heavy chain translocations were detected in 43.2% of patients by sequencing, and aligned with FISH except for 1 patient. CNAs determined by sequencing and MLPA for 22 regions were comparable in 103 samples and concordance between platforms was R2 = 0.969. Variant allele frequency (VAF) for 74 mutations were compared between sequencing and ddPCR with concordance of R2 = 0.9849. CONCLUSIONS: In summary, we have developed a targeted sequencing panel that is as robust or superior to FISH and WGS. This molecular panel is cost-effective, comprehensive, clinically actionable, and can be routinely deployed to assist risk stratification at diagnosis or posttreatment to guide sequencing of therapies.


Asunto(s)
Mieloma Múltiple , Variaciones en el Número de Copia de ADN , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/genética , Mutación , Translocación Genética , Secuenciación Completa del Genoma
2.
Eur J Pharm Sci ; 154: 105493, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32730846

RESUMEN

Toll-like receptor 4 (TLR4) recognizes various endogenous and microbial ligands and is an essential part in the innate immune system. TLR4 signaling initiates transcription factor NF-κB and production of proinflammatory cytokines. TLR4 contributes to the development or progression of various diseases including stroke, neuropathic pain, multiple sclerosis, rheumatoid arthritis and cancer, and better therapeutics are currently sought for these conditions. In this study, a library of 140 000 compounds was virtually screened and a resulting hit-list of 1000 compounds was tested using a cellular reporter system. The topoisomerase II inhibitor mitoxantrone and its analogues pixantrone and mitoxantrone (2-hydroxyethyl)piperazine were identified as inhibitors of TLR4 and NF-κB activation. Mitoxantrone was shown to bind directly to the TLR4, and pixantrone and mitoxantrone (2-hydroxyethyl)piperazine were shown to inhibit the production of proinflammatory cytokines such as tumor necrosis factor alpha (TNFα) in primary microglia. The inhibitory effect on NF-κB activation or on TNFα production was not mediated through cytotoxity at ≤ 1 µM concentration for pixantrone and mitoxantrone (2-hydroxyethyl)piperazine treated cells, as assessed by ATP counts. This study thus identifies a new mechanism of action for mitoxantrone, pixantrone, and mitoxantrone (2-hydroxyethyl)piperazine through the TLR4.


Asunto(s)
Isoquinolinas , FN-kappa B , Piperazina , Receptor Toll-Like 4 , Isoquinolinas/farmacología , Microglía , Mitoxantrona/farmacología , FN-kappa B/efectos de los fármacos , Piperazina/farmacología , Receptor Toll-Like 4/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo
3.
Neurosci Lett ; 729: 134932, 2020 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-32224226

RESUMEN

The brain histaminergic and dopaminergic systems closely interact, and some evidence also suggests significant involvement of histamine in Parkinson's disease (PD), where dopaminergic neurons degenerate. To further investigate histamine-dopamine interactions, particularly in the context of PD, a genetic lack of histamine and a mouse model of PD and levodopa-induced dyskinesia were here combined. Dopaminergic lesions were induced in histidine decarboxylase knockout and wildtype mice by 6-hydroxydopamine injections into the medial forebrain bundle. Post-lesion motor dysfunction was studied by measuring drug-induced rotational behavior and dyskinesia. Striatal tissue from both lesioned and naïve animals was used to investigate dopaminergic, serotonergic and histaminergic biomarkers. Histamine deficiency increased amphetamine-induced rotation but did not affect levodopa-induced dyskinesia. qPCR measurements revealed increased striatal expression of D1 and D2 receptor, DARPP-32, and H3 receptor mRNA, and synaptosomal release experiments in naïve mice indicated increased dopamine release. A lack of histamine thus causes pre- and postsynaptic upregulation of striatal dopaminergic neurotransmission which may be reflected in post-lesion motor behavior. Disturbances or manipulations of the histaminergic system may thus have significant consequences for dopaminergic neurotransmission and motor behavior in both healthy and disease conditions. The findings also represent new evidence for the complex interplay between dopamine and histamine within the nigrostriatal pathway.


Asunto(s)
Neuronas Dopaminérgicas/metabolismo , Discinesia Inducida por Medicamentos/metabolismo , Levodopa/farmacología , Transmisión Sináptica/efectos de los fármacos , Animales , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Discinesia Inducida por Medicamentos/genética , Ratones , Oxidopamina/metabolismo , Enfermedad de Parkinson/metabolismo , Regulación hacia Arriba/efectos de los fármacos
4.
Pharmacy (Basel) ; 7(1)2019 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-30813453

RESUMEN

The Pharmacy Education in Europe (PHARMINE) project studies pharmacy practice and education in the European Union (EU) member states. The work was carried out using an electronic survey sent to chosen pharmacy representatives. The surveys of the individual member states are now being published as reference documents for students and staff interested in research on pharmacy education in the EU, and in mobility. This paper presents the results of the PHARMINE survey on pharmacy practice and education in Finland. Pharmacies have a monopoly on the dispensation of medicines. They can also provide diagnostic services. Proviisori act as pharmacy owners and managers. They follow a five-year (M.Sc. Pharm.) degree course with a six-month traineeship. Farmaseutti, who follow a three-year (B.Sc. Pharm.) degree course (also with a six-month traineeship), can dispense medicines and counsel patients in Finland. The B.Sc. and the first three years of the M.Sc. involve the same course. The current pharmacy curriculum (revised in 2014) is based on five strands: (1) pharmacy as a multidisciplinary science with numerous opportunities in the working life, (2) basics of pharmaceutical sciences, (3) patient and medication, (4) optional studies and selected study paths, and (5) drug development and use. The learning outcomes of the pharmacy graduates include (1) basics of natural sciences: chemistry, physics, technology, biosciences required for all the students (B.Sc. and M.Sc.), (2) medicine and medication: compounding of medicines, holism of medication, pharmacology and biopharmaceutics (side-effects and interactions), patient counseling, efficacy and safety of medicines and medication, (3) comprehensive and supportive interactions of the various disciplines of pharmacy education and research: the role and significance of pharmacy as a discipline in society, the necessary skills and knowledge in scientific thinking and pharmaceutical research, and (4) basics of economics and management, multidisciplinarity, hospital pharmacy, scientific writing skills, management skills. In addition, teaching and learning of "general skills", such as the pharmacist's professional identity and the role in society as a part of the healthcare system, critical and creative thinking, problem-solving skills, personal learning skills and life-long learning, attitude and sense of responsibility, and communication skills are developed in direct association with subject-specific courses. Professional specialization studies in industrial pharmacy, and community and hospital pharmacy are given at the post-graduate level at the University of Helsinki.

5.
BMC Neurosci ; 19(1): 77, 2018 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-30497382

RESUMEN

BACKGROUND: The treatment of Parkinson's disease is often complicated by levodopa-induced dyskinesia (LID). Nicotinic acetylcholine receptor agonists can alleviate LID in animal models but may be less effective in conditions of severe dopaminergic denervation. While the mechanisms of LID remain incompletely understood, elevated corticostriatal levels of the brain-derived neurotrophic factor (BDNF) have been suggested to play a role. Here, female mice with near-total unilateral 6-hydroxydopamine-induced nigrostriatal lesions were chronically treated with levodopa, and the effects of the α7 nicotinic receptor partial agonist AZD0328 and nicotine on LID were assessed. At the end of the experiment, BDNF protein levels in the prefrontal cortex and striatum were measured. RESULTS: Five-day treatments with three escalating doses of AZD0328 and a 10-week treatment with nicotine failed to alleviate LID. BDNF levels in the lesioned striatum correlated positively with LID severity, but no evidence was found for a levodopa-induced elevation of corticostriatal BDNF in the lesioned hemisphere. The nicotine treatment decreased BDNF levels in the prefrontal cortex but had no effect on striatal BDNF. CONCLUSIONS: The findings suggest that treatment of LID with nicotinic agonists may lose its effectiveness as the disease progresses, represent further evidence for a role for BDNF in LID, and expand previous knowledge on the effects of long-term nicotine treatment on BDNF.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Dopaminérgicos/farmacología , Discinesia Inducida por Medicamentos/tratamiento farmacológico , Discinesia Inducida por Medicamentos/metabolismo , Agonistas Nicotínicos/farmacología , Trastornos Parkinsonianos/tratamiento farmacológico , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Dopamina/deficiencia , Dopaminérgicos/efectos adversos , Discinesia Inducida por Medicamentos/patología , Femenino , Furanos/farmacología , Levodopa/efectos adversos , Levodopa/farmacología , Ratones Endogámicos C57BL , Nicotina/farmacología , Trastornos Parkinsonianos/metabolismo , Trastornos Parkinsonianos/patología , Quinuclidinas/farmacología , Distribución Aleatoria , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
6.
Neuropharmacology ; 138: 371-380, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29940207

RESUMEN

Preclinical studies suggest the involvement of various subtypes of nicotinic acetylcholine receptors in the pathophysiology of Parkinson's disease, a neurodegenerative disorder characterized by the death of dopaminergic neurons in the substantia nigra pars compacta (SNC). We studied for the first time the effects of α5 nicotinic receptor subunit gene deletion on motor behavior and neurodegeneration in mouse models of Parkinson's disease and levodopa-induced dyskinesia. Unilateral dopaminergic lesions were induced in wild-type and α5-KO mice by 6-hydroxydopamine injections into the striatum or the medial forebrain bundle. Subsequently, rotational behavior induced by dopaminergic drugs was measured. A subset of animals received chronic treatments with levodopa and nicotine to assess levodopa-induced dyskinesia and antidyskinetic effects by nicotine. SNC lesion extent was assessed with tyrosine hydroxylase immunohistochemistry and stereological cell counting. Effects of α5 gene deletion on the dopaminergic system were investigated by measuring ex vivo striatal dopamine transporter function and protein expression, dopamine and metabolite tissue concentrations and dopamine receptor mRNA expression. Hemiparkinsonian α5-KO mice exhibited attenuated rotational behavior after amphetamine injection and attenuated levodopa-induced dyskinesia. In the intrastriatal lesion model, dopaminergic cell loss in the medial cluster of the SNC was less severe in α5-KO mice. Decreased striatal dopamine uptake in α5-KO animals suggested reduced dopamine transporter function as a mechanism of attenuated neurotoxicity. Nicotine reduced dyskinesia severity in wild-type but not α5-KO mice. The attenuated dopaminergic neurodegeneration and motor dysfunction observed in hemiparkinsonian α5-KO mice suggests potential for α5 subunit-containing nicotinic receptors as a novel target in the treatment of Parkinson's disease.


Asunto(s)
Neuronas Dopaminérgicas/metabolismo , Actividad Motora/fisiología , Enfermedades Neurodegenerativas/metabolismo , Trastornos Parkinsonianos/metabolismo , Receptores Nicotínicos/deficiencia , Anfetamina/farmacología , Animales , Antiparkinsonianos/efectos adversos , Antiparkinsonianos/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Estimulantes del Sistema Nervioso Central/farmacología , Dopamina/metabolismo , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/patología , Discinesia Inducida por Medicamentos/metabolismo , Femenino , Lateralidad Funcional , Levodopa/efectos adversos , Levodopa/farmacología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Actividad Motora/efectos de los fármacos , Enfermedades Neurodegenerativas/patología , Oxidopamina , Trastornos Parkinsonianos/tratamiento farmacológico , Trastornos Parkinsonianos/patología , ARN Mensajero/metabolismo , Receptores Dopaminérgicos/metabolismo , Receptores Nicotínicos/genética
7.
Neurosci Lett ; 672: 40-45, 2018 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-29474871

RESUMEN

The treatment of Parkinson's disease is often complicated by levodopa-induced dyskinesia (LID), and antidyskinetic treatment options are currently sparse. Nicotinic acetylcholine receptors have been suggested as potential targets for treatment of LID, as nicotinic agonists have been reported to alleviate LID in animal models. We aimed at the first independent replication of an antidyskinetic effect by nicotine using a mouse model of LID, and at investigation of its mechanisms by studying the release of [3H]dopamine from synaptosomes prepared from the dorsal and ventral striatum. Chronic nicotine treatment in drinking water inhibited the development of LID in mice lesioned unilaterally with 6-hydroxydopamine and treated chronically with levodopa and benserazide. The antidyskinetic nicotine treatment had no effect on [3H]dopamine release mediated by α4ß2* nicotinic receptors, but decreased α6ß2*-mediated [3H]dopamine release in the lesioned dorsal striatum and the ventral striatum. In addition, nicotine treatment restored [3H]dopamine release in the lesioned ventral striatum to intact levels. The results support a role for nicotinic receptors as drug targets for treatment of LID, and suggest that striatal presynaptic α6ß2* receptors are important mediators of nicotine's antidyskinetic effect.


Asunto(s)
Cuerpo Estriado/efectos de los fármacos , Dopamina/metabolismo , Discinesia Inducida por Medicamentos/tratamiento farmacológico , Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Sinaptosomas/metabolismo , Animales , Cuerpo Estriado/metabolismo , Discinesia Inducida por Medicamentos/metabolismo , Levodopa/farmacología , Ratones , Nicotina/uso terapéutico , Agonistas Nicotínicos/uso terapéutico
8.
Neuroscience ; 376: 188-203, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29374538

RESUMEN

Histamine H3 receptors are widely distributed Gi-coupled receptors whose activation reduces neuronal activity and inhibits release of numerous neurotransmitters. Although these receptors are abundantly expressed in the striatum, their modulatory role on activity-dependent dopamine release is not well understood. Here, we observed that histamine H3 receptor activation indirectly diminishes dopamine overflow in the ventral striatum by reducing cholinergic interneuron activity. Acute brain slices from C57BL/6 or channelrhodopsin-2-transfected DAT-cre mice were obtained, and dopamine transients evoked either electrically or optogenetically were measured by fast-scan cyclic voltammetry. The H3 agonist α-methylhistamine significantly reduced electrically- evoked dopamine overflow, an effect blocked by the nicotinic acetylcholine receptor antagonist dihydro-ß-erythroidine, suggesting involvement of cholinergic interneurons. None of the drug treatments targeting H3 receptors affected optogenetically evoked dopamine overflow, indicating that direct H3-modulation of dopaminergic axons is unlikely. Next, we used qPCR and confirmed the expression of histamine H3 receptor mRNA in cholinergic interneurons, both in ventral and dorsal striatum. Activation of H3 receptors by α-methylhistamine reduced spontaneous firing of cholinergic interneurons in the ventral, but not in the dorsal striatum. Resting membrane potential and number of spontaneous action potentials in ventral-striatal cholinergic interneurons were significantly reduced by α-methylhistamine. Acetylcholine release from isolated striatal synaptosomes, however, was not altered by α-methylhistamine. Together, these results indicate that histamine H3 receptors are important modulators of dopamine release, specifically in the ventral striatum, and that they do so by decreasing the firing rate of cholinergic neurons and, consequently, reducing cholinergic tone on dopaminergic axons.


Asunto(s)
Acetilcolina/metabolismo , Dopamina/metabolismo , Interneuronas/metabolismo , Receptores Histamínicos H3/metabolismo , Estriado Ventral/metabolismo , Animales , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Femenino , Agonistas de los Receptores Histamínicos/farmacología , Interneuronas/efectos de los fármacos , Masculino , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Metilhistaminas/farmacología , Ratones Endogámicos C57BL , Ratones Transgénicos , Optogenética , ARN Mensajero/metabolismo , Sinaptosomas/metabolismo , Técnicas de Cultivo de Tejidos , Estriado Ventral/efectos de los fármacos
9.
Pharmacy (Basel) ; 5(2)2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28970441

RESUMEN

In order to meet the expectations to act as an expert in the health care profession, it is of utmost importance that pharmacy education creates knowledge and skills needed in today's working life. Thus, the planning of the curriculum should be based on relevant and up-to-date learning outcomes. In the University of Helsinki, a university wide curriculum reform called 'the Big Wheel' was launched in 2015. After the reform, the basic degrees of the university are two-cycle (Bachelor-Master) and competence-based, where the learning outcomes form a solid basis for the curriculum goals and implementation. In the Faculty of Pharmacy, this curriculum reform was conducted in two phases during 2012-2016. The construction of the curriculum was based on the most relevant learning outcomes concerning working life via high quality first (Bachelor of Science in Pharmacy) and second (Master of Science in Pharmacy) cycle degree programs. The reform was kicked off by interviewing all the relevant stakeholders: students, teachers, and pharmacists/experts in all the working life sectors of pharmacy. Based on these interviews, the intended learning outcomes of the Pharmacy degree programs were defined including both subject/contents-related and generic skills. The curriculum design was based on the principles of constructive alignment and new structures and methods were applied in order to foster the implementation of the learning outcomes. During the process, it became evident that a competence-based curriculum can be created only in close co-operation with the stakeholders, including teachers and students. Well-structured and facilitated co-operation amongst the teachers enabled the development of many new and innovative teaching practices. The European Union funded PHAR-QA project provided, at the same time, a highly relevant framework to compare the curriculum development in Helsinki against Europe-wide definitions of competences and learning outcomes in pharmacy education.

10.
Alcohol Clin Exp Res ; 40(2): 329-34, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26842251

RESUMEN

BACKGROUND: The aim of this study was to examine possible differences in nicotinic acetylcholine receptors and responses in rats with genetic preference or avoidance for alcohol. This was done by using 2 rat lines with high alcohol preference (Alko Alcohol [AA]) or alcohol avoidance (Alko Non-Alcohol [ANA]). METHODS: Locomotor activity was measured following nicotine and histamine H3 receptor (H3R) antagonist treatment. In situ hybridization and receptor ligand binding experiments were used in drug-naïve animals to examine the expression of different α nicotinic receptor subunits. RESULTS: The AA rats were found to be more sensitive to the stimulatory effect of a low dose of nicotine than ANA rats, which were not significantly activated. Combination of histamine H3R antagonist, JNJ-39220675, and nicotine resulted to similar locomotor activation as nicotine alone. To further understand the mechanism underlying the difference in nicotine response in AA and ANA rats, we studied the expression of α5, α6, and α7 nicotinic receptor subunits in specific brain areas of AA and ANA rats. We found no differences in the expression of α5 nicotinic receptor subunits in the medial habenula and hippocampus or in α6 subunit in the ventral tegmental area and substantia nigra. However, the level of α7 nicotinic receptor subunit mRNA was significantly lower in the tuberomamillary nucleus of posterior hypothalamus of alcohol-preferring AA rats than in alcohol-avoiding ANA rats. Also the hypothalamic [125I-α-bungarotoxin binding was lower in AA rats indicating lower levels of α7 nicotinic receptors. CONCLUSIONS: The lower expression and receptor binding of α7 nicotinic receptors in the tuberomamillary nucleus of AA rats suggest a difference in the regulation of brain histamine neurons between the rat lines since the α7 nicotinic receptors are located in histaminergic neurons. Stronger nicotine-induced locomotor response, mediated partially via α7 receptors, and previously described high alcohol consumption in AA rats could be explained by the found difference in tuberomamillary α7 receptor levels.


Asunto(s)
Consumo de Bebidas Alcohólicas/fisiopatología , Hipotálamo/fisiología , Nicotina/farmacología , Receptor Nicotínico de Acetilcolina alfa 7/fisiología , Abstinencia de Alcohol , Animales , Azepinas/farmacología , Antagonistas de los Receptores Histamínicos/farmacología , Área Hipotalámica Lateral/química , Área Hipotalámica Lateral/fisiología , Hipotálamo/química , Hibridación in Situ , Masculino , Actividad Motora/efectos de los fármacos , Nicotina/administración & dosificación , Piridinas/farmacología , Ratas , Receptor Nicotínico de Acetilcolina alfa 7/análisis , Receptor Nicotínico de Acetilcolina alfa 7/antagonistas & inhibidores , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
11.
Biochem Pharmacol ; 97(4): 542-549, 2015 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-26231941

RESUMEN

Methadone is a long-acting opioid agonist that is frequently prescribed as a treatment for opioid addiction. Almost all methadone maintenance patients are smokers, and there is a correlation between smoking habit and use of methadone. Methadone administration increases tobacco smoking, and heavy smokers use higher doses of methadone. Nevertheless, methadone maintenance patients are willing to quit smoking although their quit rates are low. Studies on nicotine-methadone interactions provide an example of the bedside-to-bench approach, i.e., observations in clinical settings have been studied experimentally in vivo and in vitro. In vivo studies have revealed the interplay between nicotine and the endogenous opioid system. At the receptor level, methadone has been shown to be an agonist of human α7 nAChRs and a non-competitive antagonist of human α4ß2 and α3* nAChRs. These drugs do not have significant interactions at the level of drug metabolism, and thus the interaction is most likely pharmacodynamic. The net effect of the interaction may depend on individual characteristics because pharmacogenetic factors influence the disposition of both methadone and nicotine.


Asunto(s)
Analgésicos Opioides/farmacología , Metadona/farmacología , Fumar , Humanos , Agonistas Nicotínicos/farmacología , Cese del Hábito de Fumar , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
12.
Basic Clin Pharmacol Toxicol ; 116(4): 321-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25196810

RESUMEN

Nicotine-methadone interactions have been studied in human beings and in various experimental settings regarding addiction, reward and pain. Most methadone maintenance treatment patients are smokers, and methadone administration has been shown to increase cigarette smoking. Previous in vitro studies have shown that methadone is a non-competitive antagonist at rat α3ß4 nicotinic acetylcholine receptors (nAChR) and an agonist at human α7 nAChRs. In this study, we used cell lines expressing human α4ß2, α7 and α3* nAChRs to compare the interactions of methadone at the various human nAChRs under the same experimental conditions. A [(3) H]epibatidine displacement assay was used to determine whether methadone binds to the nicotinic receptors, and (86) Rb(+) efflux and changes in intracellular calcium [Ca(2+) ]i were used to assess changes in the functional activity of the receptors. Methadone displaced [(3) H]epibatidine from nicotinic agonist-binding sites in SH-EP1-hα7 and SH-SY5Y cells, but not in SH-EP1-hα4ß2 cells. The Ki values for methadone were 6.3 µM in SH-EP1-hα7 cells and 19.4 µM and 1008 µM in SH-SY5Y cells. Methadone increased [Ca(2+) ]i in all cell lines in a concentration-dependent manner, and in SH-EP1-hα7 cells, the effect was more pronounced than the effect of nicotine treatment. In SH-EP1-hα4ß2 cells, the effect of methadone was negligible compared to that of nicotine. Methadone pre-treatment abolished the nicotine-induced response in [Ca(2+) ]i in all cell lines expressing nAChRs. In SH-EP1-hα4ß2 and SH-SY5Y cells, methadone had no effect on the (86) Rb(+) efflux, but it antagonized the nicotine-induced (86) Rb(+) ion efflux in a non-competitive manner. These results suggest that methadone is an agonist at human α7 nAChRs and a non-competitive antagonist at human α4ß2 and α3* nAChRs. This study adds further support to the previous findings that opioids interact with nAChRs, which may underlie their frequent co-administration in human beings and might be of interest to the field of drug discovery.


Asunto(s)
Metadona/farmacología , Narcóticos/farmacología , Antagonistas Nicotínicos/farmacología , Receptores Nicotínicos/efectos de los fármacos , Unión Competitiva/efectos de los fármacos , Compuestos Bicíclicos Heterocíclicos con Puentes/metabolismo , Calcio/metabolismo , Células Cultivadas , Humanos , Agonistas Nicotínicos/metabolismo , Piridinas/metabolismo , Radioisótopos de Rubidio
13.
J Neurochem ; 130(2): 185-98, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24661093

RESUMEN

Nicotinic acetylcholine receptors (nAChR) of the α6ß2* subtype (where *indicates the possible presence of additional subunits) are prominently expressed on dopaminergic neurons. Because of this, their role in tobacco use and nicotine dependence has received much attention. Previous studies have demonstrated that α6ß2*-nAChR are down-regulated following chronic nicotine exposure (unlike other subtypes that have been investigated - most prominently α4ß2* nAChR). This study examines, for the first time, effects across a comprehensive chronic nicotine dose range. Chronic nicotine dose-responses and quantitative ligand-binding autoradiography were used to define nicotine sensitivity of changes in α4ß2*-nAChR and α6ß2*-nAChR expression. α6ß2*-nAChR down-regulation by chronic nicotine exposure in dopaminergic and optic-tract nuclei was ≈three-fold more sensitive than up-regulation of α4ß2*-nAChR. In contrast, nAChR-mediated [(3) H]-dopamine release from dopamine-terminal region synaptosomal preparations changed only in response to chronic treatment with high nicotine doses, whereas dopaminergic parameters (transporter expression and activity, dopamine receptor expression) were largely unchanged. Functional measures in olfactory tubercle preparations were made for the first time; both nAChR expression levels and nAChR-mediated functional measures changed differently between striatum and olfactory tubercles. These results show that functional changes measured using synaptosomal [(3) H]-DA release are primarily owing to changes in nAChR, rather than in dopaminergic, function. This study examined dose-response relationships for murine α6ß2*-nicotinic acetylcholine receptor (nAChR) down-regulation by chronic nicotine treatment. The ID50 value for α6ß2* down-regulation (35 nM) is ≈ 3x lower than the ED50 value for α4ß2* nAChR up-regulation (95 nM), both well within the range reached by human smokers. Chronic nicotine treatment altered α6ß2*- and α4ß2*-nAChR-mediated [(3) H]-dopamine release from striatal and olfactory tubercle synaptosomes, but dopaminergic parameters were largely unaffected. We conclude that functional changes are primarily driven by altered nAChR activity.


Asunto(s)
Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Receptores Nicotínicos/efectos de los fármacos , Alcaloides/farmacología , Animales , Autorradiografía , Azocinas/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/metabolismo , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo/efectos de los fármacos , Técnicas In Vitro , Ratones , Ratones Noqueados , Neostriado/citología , Neostriado/efectos de los fármacos , Neostriado/metabolismo , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Bulbo Olfatorio/citología , Bulbo Olfatorio/efectos de los fármacos , Bulbo Olfatorio/metabolismo , Piridinas/metabolismo , Piridinas/farmacología , Quinolizinas/farmacología , Ensayo de Unión Radioligante , Sinaptosomas/efectos de los fármacos , Sinaptosomas/metabolismo
14.
Front Cell Neurosci ; 7: 135, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24009556

RESUMEN

Glutamate uptake, mediated by electrogenic glutamate transporters largely localized in astrocytes, is responsible for the clearance of glutamate released during excitatory synaptic transmission. Glutamate uptake also determines the availability of glutamate for extrasynaptic glutamate receptors. The efficiency of glutamate uptake is commonly estimated from the amplitude of transporter current recorded in astrocytes. We recorded currents in voltage-clamped hippocampal CA1 stratum radiatum astrocytes in rat hippocampal slices induced by electrical stimulation of the Schaffer collaterals. A Ba(2+)-sensitive K(+) current mediated by inward rectifying potassium channels (Kir) accompanied the transporter current. Surprisingly, Ba(2+) not only suppressed the K(+) current and changed holding current (presumably, mediated by Kir) but also increased the transporter current at lower concentrations. However, Ba(2+) did not significantly increase the uptake of aspartate in cultured astrocytes, suggesting that increase in the amplitude of the transporter current does not always reflect changes in glutamate uptake.

15.
Neuropharmacology ; 73: 19-30, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23688922

RESUMEN

Nicotinic acetylcholine receptors (nAChRs) containing either the α4 and/or α6 subunit are robustly expressed in dopaminergic nerve terminals in dorsal striatum where they are hypothesized to modulate dopamine (DA) release via acetylcholine (ACh) stimulation from cholinergic interneurons. However, pharmacological blockade of nAChRs or genetic deletion of individual nAChR subunits, including α4 and α6, in mice, yields little effect on motor behavior. Based on the putative role of nAChRs containing the α4 subunit in modulation of DA in dorsal striatum, we hypothesized that mice expressing a single point mutation in the α4 nAChR subunit, Leu9'Ala, that renders nAChRs hypersensitive to agonist, would exhibit exaggerated differences in motor behavior compared to WT mice. To gain insight into these differences, we challenged WT and Leu9'Ala mice with the α4ß2 nAChR antagonist dihydro-ß-erythroidine (DHßE). Interestingly, in Leu9'Ala mice, DHßE elicited a robust, reversible motor impairment characterized by hypolocomotion, akinesia, catalepsy, clasping, and tremor; whereas the antagonist had little effect in WT mice at all doses tested. Pre-injection of nicotine (0.1 mg/kg) blocked DHßE-induced motor impairment in Leu9'Ala mice confirming that the phenotype was mediated by antagonism of nAChRs. In addition, SKF82958 (1 mg/kg) and amphetamine (5 mg/kg) prevented the motor phenotype. DHßE significantly activated more neurons within striatum and substantia nigra pars reticulata in Leu9'Ala mice compared to WT animals, suggesting activation of the indirect motor pathway as the circuit underlying motor dysfunction. ACh evoked DA release from Leu9'Ala striatal synaptosomes revealed agonist hypersensitivity only at α4(non-α6)* nAChRs. Similarly, α6 nAChR subunit deletion in an α4 hypersensitive nAChR (Leu9'Ala/α6 KO) background had little effect on the DHßE-induced phenotype, suggesting an α4(non-α6)* nAChR-dependent mechanism. Together, these data indicate that α4(non-α6)* nAChR have an impact on motor output and may be potential molecular targets for treatment of disorders associated with motor impairment.


Asunto(s)
Conducta Animal/fisiología , Receptores Nicotínicos/fisiología , Acetilcolina/farmacología , Anfetamina/farmacología , Animales , Conducta Animal/efectos de los fármacos , Benzazepinas/farmacología , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/fisiología , Dihidro-beta-Eritroidina/antagonistas & inhibidores , Dihidro-beta-Eritroidina/farmacología , Dopamina/metabolismo , Agonistas de Dopamina/farmacología , Femenino , Técnicas de Sustitución del Gen , Masculino , Ratones , Ratones Noqueados , Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Antagonistas Nicotínicos/farmacología , Mutación Puntual , Receptores Nicotínicos/efectos de los fármacos , Receptores Nicotínicos/genética , Sustancia Negra/efectos de los fármacos , Sustancia Negra/fisiología , Sinaptosomas/efectos de los fármacos , Sinaptosomas/metabolismo
16.
Eur J Pharmacol ; 701(1-3): 57-64, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23340223

RESUMEN

Nicotine and opioids share several behavioral and rewarding properties. Although both opioids and nicotine have their own specific mechanism of action, there is empirical and experimental evidence of interactions between these drugs. We studied receptor-level interactions of nicotine and morphine at α4ß2, α7 and α3(⁎) nicotinic acetylcholine receptors. [(3)H]epibatidine displacement was used to determine if morphine binds competitively to nicotinic acetylcholine receptors. Functional interactions of morphine and nicotine were studied with calcium fluorometry and (86)Rb(+) efflux assays. Morphine displaced [(3)H]epibatidine from nicotinic agonist binding sites in all cell lines studied. The Ki values for morphine were 13.2µM in SH-EP1-hα4ß2 cells, 0.16µM and 126µM in SH-SY5Y cells and 43.7µM in SH-EP1-hα7 cells. In SH-EP1-hα4ß2 cells expressing α4ß2 nicotinic acetylcholine receptors, morphine acted as a partial agonist of (86)Rb(+) efflux comparable to cytisine (with EC50 values of 53.3µM for morphine and 5.38µM for cytisine). The effect of morphine was attenuated concentration-dependently by the nicotinic antagonist mecamylamine. In the SH-SY5Y cell line expressing several subtypes of nicotinic acetylcholine receptors morphine had an inhibitory effect on nicotine induced (86)Rb(+) ion efflux mediated by α3(⁎) nicotinic acetylcholine receptors. These results suggest that morphine acts as a partial agonist at α4ß2 nicotinic acetylcholine receptors and as a weak antagonist at α3(⁎) nicotinic acetylcholine receptors.


Asunto(s)
Morfina/farmacología , Nicotina/farmacología , Receptores Nicotínicos/metabolismo , Unión Competitiva , Compuestos Bicíclicos Heterocíclicos con Puentes/metabolismo , Calcio/metabolismo , Línea Celular Tumoral , Interacciones Farmacológicas , Humanos , Morfina/metabolismo , Nicotina/metabolismo , Piridinas/metabolismo , Radioisótopos de Rubidio/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7
17.
Nicotine Tob Res ; 14(6): 720-33, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22241830

RESUMEN

INTRODUCTION: The role of the nicotinic acetylcholine receptor gene cluster on chromosome 15q24-25 in the etiology of nicotine dependence (ND) is still being defined. In this study, we included all 15 tagging single nucleotide polymorphisms (SNPs) within the CHRNA5-CHRNA3-CHRNB4 cluster and tested associations with 30 smoking-related phenotypes. METHODS: The study sample was ascertained from the Finnish Twin Cohort study. Twin pairs born 1938-1957 and concordant for a history of cigarette smoking were recruited along with their family members (mainly siblings), as part of the Nicotine Addiction Genetics consortium. The study sample consisted of 1,428 individuals (59% males) from 735 families, with mean age 55.6 years. RESULTS: We detected multiple novel associations for ND. DSM-IV ND symptoms associated significantly with the proxy SNP Locus 1 (rs2036527, p = .000009) and Locus 2 (rs578776, p = .0001) and tolerance factor of the Nicotine Dependence Syndrome Scale (NDSS) showed suggestive association to rs11636753 (p = .0059), rs11634351 (p = .0069), and rs1948 (p = .0071) in CHRNB4. Furthermore, we report significant association with DSM-IV ND diagnosis (rs2036527, p = .0003) for the first time in a Caucasian population. Several SNPs indicated suggestive association for traits related to ages at smoking initiation. Also, rs11636753 in CHRNB4 showed suggestive association with regular drinking (p = .0029) and the comorbidity of depression and ND (p = .0034). CONCLUSIONS: We demonstrate novel associations of DSM-IV ND symptoms and the NDSS tolerance subscale. Our results confirm and extend association findings for other ND measures. We show pleiotropic effects of this gene cluster on multiple measures of ND and also regular drinking and the comorbidity of ND and depression.


Asunto(s)
Familia de Multigenes , Proteínas del Tejido Nervioso/genética , Receptores Nicotínicos/genética , Tabaquismo/genética , Edad de Inicio , Alelos , Cromosomas Humanos Par 15/genética , Cromosomas Humanos Par 15/metabolismo , Estudios de Cohortes , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Frecuencia de los Genes , Sitios Genéticos , Pleiotropía Genética , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/metabolismo , Fenotipo , Polimorfismo de Nucleótido Simple , Receptores Nicotínicos/metabolismo , Fumar/genética , Tabaquismo/metabolismo , Población Blanca/genética
18.
Nicotine Tob Res ; 13(8): 686-90, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21498873

RESUMEN

INTRODUCTION: Genetic effects contribute to individual differences in smoking behavior. Persistence to smoke despite known harmful health effects is mostly driven by nicotine addiction. As the physiological effects of nicotine are mediated by nicotinic acetylcholine receptors (nAChRs), we aimed at examining whether single nucleotide polymorphisms (SNPs) residing in nAChR subunit (CHRN) genes, other than CHRNA3/CHRNA5/CHRNB4 gene cluster previously showing association in our sample, are associated with smoking quantity or serum cotinine levels. METHODS: The study sample consisted of 485 Finnish adult daily smokers (age 30-75 years, 59% men) assessed for the number of cigarettes smoked per day (CPD) and serum cotinine level. We first studied SNPs residing on selected nAChR subunit genes (CHRNA2, CHRNA4, CHRNA6/CHRNB3, CHRNA7, CHRNA9, CHRNA10, CHRNB2, CHRNG/CHRND) genotyped within a genome-wide association study for single SNP and multiple SNP associations by ordinal regression. Next, we explored individual haplotype associations using sliding window technique. RESULTS: At one of the 8 loci studied, CHRNG/CHRND (chr2), single SNP (rs1190452), multiple SNP, and 2-SNP haplotype analyses (SNPs rs4973539-rs1190452) all showed statistically significant association with cotinine level. The median cotinine levels varied between the 2-SNP haplotypes from 220 ng/ml (AA haplotype) to 249 ng/ml (AG haplotype). We did not observe significant associations with CPD. CONCLUSIONS: These results provide further evidence that the γ-δ nAChR subunit gene region is associated with cotinine levels but not with the number of CPD, illustrating the usefulness of biomarkers in genetic analyses.


Asunto(s)
Frecuencia de los Genes/genética , Predisposición Genética a la Enfermedad/epidemiología , Polimorfismo de Nucleótido Simple/genética , Receptores Nicotínicos/genética , Fumar/genética , Tabaquismo/genética , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Finlandia/epidemiología , Estudio de Asociación del Genoma Completo , Haplotipos , Humanos , Desequilibrio de Ligamiento/genética , Masculino , Persona de Mediana Edad , Fumar/epidemiología , Tabaquismo/epidemiología
19.
J Pharmacol Exp Ther ; 337(1): 187-200, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21228066

RESUMEN

Chronic nicotine treatment elicits a brain region-selective increase in the number of high-affinity agonist binding sites, a phenomenon termed up-regulation. Nicotine-induced up-regulation of α4ß2-nicotinic acetylcholine receptors (nAChRs) in cell cultures results from increased assembly and/or decreased degradation of nAChRs, leading to increased nAChR protein levels. To evaluate whether the increased binding in mouse brain results from an increase in nAChR subunit proteins, C57BL/6 mice were treated with nicotine by chronic intravenous infusion. Tissue sections were prepared, and binding of [(125)I]3-((2S)-azetidinylmethoxy)-5-iodo-pyridine (A85380) to ß2*-nAChR sites, [(125)I]monoclonal antibody (mAb) 299 to α4 nAChR subunits, and [(125)I]mAb 270 to ß2 nAChR subunits was determined by quantitative autoradiography. Chronic nicotine treatment dose-dependently increased binding of all three ligands. In regions that express α4ß2-nAChR almost exclusively, binding of all three ligands increased coordinately. However, in brain regions containing significant ß2*-nAChR without α4 subunits, relatively less increase in mAb 270 binding to ß2 subunits was observed. Signal intensity measured with the mAbs was lower than that with [(125)I]A85380, perhaps because the small ligand penetrated deeply into the sections, whereas the much larger mAbs encountered permeability barriers. Immunoprecipitation of [(125)I]epibatidine binding sites with mAb 270 in select regions of nicotine-treated mice was nearly quantitative, although somewhat less so with mAb 299, confirming that the mAbs effectively recognize their targets. The patterns of change measured using immunoprecipitation were comparable with those determined autoradiographically. Thus, increases in α4ß2*-nAChR binding sites after chronic nicotine treatment reflect increased nAChR protein.


Asunto(s)
Encéfalo/efectos de los fármacos , Nicotina/administración & dosificación , Agonistas Nicotínicos/metabolismo , Agonistas Nicotínicos/farmacología , Receptores Nicotínicos/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Animales , Sitios de Unión/efectos de los fármacos , Sitios de Unión/fisiología , Encéfalo/metabolismo , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Regulación hacia Arriba/fisiología
20.
Eur J Pharmacol ; 640(1-3): 87-93, 2010 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-20457149

RESUMEN

Maternal cigarette smoking during pregnancy can result in behavioural problems of the offspring. Although the causative agent in tobacco smoke that leads to these aberrations is not known, some studies using animal models have supported the hypothesis that nicotine may cause impairments in fatal and neonatal development. However, in many of the animal studies nicotine has been administered by subcutaneous injections, which could lead to significant fetal hypoxia; some routes of drug administration included stressful procedures to pregnant dams that could create unfavorable fetal environment. In this study, mice were exposed to nicotine via drinking solution. The effects of nicotine exposure throughout early development on behavioural measures during adolescence and adulthood were examined. Adult female dams were allowed to orally self-administer a saccharin, or nicotine plus saccharin solution during gestation and lactation. Following weaning, plasma nicotine concentrations were measured in nicotine-exposed dams, and their offspring were tested using various behavioural measures. [3H]Epibatidine binding was also measured in the cortex and hippocampus at two different time points in the nicotine-exposed adolescents. The results of the study indicate that exposure to nicotine throughout early development influenced intravenous nicotine self-administration, social interactions and performance under a forced swim test. Exposure throughout early development to nicotine however did not affect [3H]epibatidine binding in the hippocampus and cortex.


Asunto(s)
Conducta Animal/efectos de los fármacos , Desarrollo Fetal , Exposición Materna/efectos adversos , Nicotina/administración & dosificación , Nicotina/farmacología , Animales , Conducta Animal/fisiología , Compuestos Bicíclicos Heterocíclicos con Puentes/metabolismo , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Cotinina/sangre , Femenino , Lactancia , Ratones , Actividad Motora/efectos de los fármacos , Nicotina/sangre , Embarazo , Piridinas/metabolismo , Autoadministración , Fumar/efectos adversos , Natación , Factores de Tiempo
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