42 research outputs found

    Synthesis and Structure-Affinity Relationships of Spirocyclic Benzopyrans with Exocyclic Amino Moiety

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    \u3c31 and/or \u3c32 receptors play a crucial role in pathological conditions such as pain, neurodegenerative disorders, and cancer. A set of spirocyclic cyclohexanes with diverse O-heterocycles and amino moieties (general structure III) was prepared and pharmacologically evaluated. In structure-activity relationships studies, the \u3c31 receptor affinity and \u3c31:\u3c32 selectivity were correlated with the stereochemistry, the kind and substitution pattern of the O-heterocycle, and the substituents at the exocyclic amino moiety. cis-configured 2-benzopyran cis-11b bearing a methoxy group and a tertiary cyclohexylmethylamino moiety showed the highest \u3c31 affinity ( Ki = 1.9 nM) of this series of compounds. In a Ca2+ influx assay, cis-11b behaved as a \u3c31 antagonist. cis-11b reveals high selectivity over \u3c32 and opioid receptors. The interactions of the novel \u3c31 ligands were analyzed on the molecular level using the recently reported X-ray crystal structure of the \u3c31 receptor protein. The protonated amino moiety forms a persistent salt bridge with E172. The spiro[benzopyran-1,1'-cyclohexane] scaffold and the cyclohexylmethyl moiety occupy two hydrophobic pockets. Exchange of the N-cyclohexylmethyl moiety by a benzyl group led unexpectedly to potent and selective \u3bc-opioid receptor ligands

    Acid Sphingomyelinase Impacts Canonical Transient Receptor Potential Channels 6 (TRPC6) Activity in Primary Neuronal Systems

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    The acid sphingomyelinase (ASM)/ceramide system exhibits a crucial role in the pathology of major depressive disorder (MDD). ASM hydrolyzes the abundant membrane lipid sphingomyelin to ceramide that regulates the clustering of membrane proteins via microdomain and lipid raft organization. Several commonly used antidepressants, such as fluoxetine, rely on the functional inhibition of ASM in terms of their antidepressive pharmacological effects. Transient receptor potential canonical 6 (TRPC6) ion channels are located in the plasma membrane of neurons and serve as receptors for hyperforin, a phytochemical constituent of the antidepressive herbal remedy St. John’s wort. TRPC6 channels are involved in the regulation of neuronal plasticity, which likely contributes to their antidepressant effect. In this work, we investigated the impact of reduced ASM activity on the TRPC6 function in neurons. A lipidomic analysis of cortical brain tissue of ASM deficient mice revealed a decrease in ceramide/sphingomyelin molar ratio and an increase in sphingosine. In neurons with ASM deletion, hyperforin-mediated Ca2+-influx via TRPC6 was decreased. Consequently, downstream activation of nuclear phospho-cAMP response element-binding protein (pCREB) was changed, a transcriptional factor involved in neuronal plasticity. Our study underlines the importance of balanced ASM activity, as well as sphingolipidome composition for optimal TRPC6 function. A better understanding of the interaction of the ASM/ceramide and TRPC6 systems could help to draw conclusions about the pathology of MDD

    Initiation and completion of treatment for latent tuberculosis infection in migrants globally:a systematic review and meta-analysis

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    BACKGROUND: Latent tuberculosis infection (LTBI) is one of the most prevalent infections globally and can lead to the development of active tuberculosis disease. In many low-burden countries, LTBI is concentrated within migrant populations often because of a higher disease burden in the migrant's country of origin. National programmes consequently focus on screening and treating LTBI in migrants to prevent future tuberculosis cases; however, how effective these programmes are is unclear. We aimed to assess LTBI treatment initiation and outcomes among migrants, and the factors that influence both. METHODS: For this systematic review and meta-analysis, we searched Embase, MEDLINE, and Global Health, and manually searched grey literature from Jan 1, 2000, to April 21, 2020. We included primary research articles reporting on LTBI treatment initiation or completion, or both, in migrants and excluded articles in which data were not stratified by migrant status, or in which the data were related to outcomes before 2000. There were no geographical or language restrictions. All included studies were quality appraised using recognised tools depending on their design, and we assessed the heterogeneity of analyses using I2. We extracted data on the numbers of migrants initiating and completing treatment. Our primary outcomes were LTBI treatment initiation and completion in migrants (defined as foreign-born). We used random-effects meta-regression to examine the influence of factors related to these outcomes. The study is registered with PROSPERO (CRD42019140338). FINDINGS: 2199 publications were retrieved screened, after which 39 publications from 13 mostly high-income, low-burden countries were included in our analyses, with treatment initiation and completion data reported for 31 598 migrants positive for LTBI, with not all articles reporting the full pathway from initiation to completion. The pooled estimate for the true proportion of migrants testing positive who initiated treatment was 69% (95% CI 51-84; I2= 99·62%; 4409 of 8764). The pooled estimate for the true proportion of migrants on treatment in datasets, who subsequently completed it was 74% (95% CI = 66-81; I2= 99·19%; 15 516 of 25 629). Where data were provided for the entire treatment pathway, the pooled estimate for the true proportion of migrants who initiated and completed treatment after a positive test was only 52% (95% CI 40-64; I2= 98·90%; 3289 of 6652). Meta-regression showed that LTBI programmes are improving, with more recent reported data (2010-20) associated with better rates of treatment initiation and completion, with multiple complex factors affecting treatment outcomes in migrants. INTERPRETATION: Although our analysis highlights that LTBI treatment initiation and completion in migrants has improved considerably from 2010-20, there is still room for improvement, with drop out reported along the entire treatment pathway. The delivery of these screening and treatment programmes will require further strengthening if the targets to eradicate tuberculosis in low-incidence countries are to be met, with greater focus needed on engaging migrants more effectively in the clinic and understanding the diverse and unique barriers and facilitators to migrants initiating and completing treatment. FUNDING: European Society of Clinical Microbiology and Infectious Diseases, the Rosetrees Trust, the National Institute for Health Research, and the Academy of Medical Sciences

    Hyperforin Potentiates Antidepressant-Like Activity of Lanicemine in Mice

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    N-methyl-D-aspartate receptor (NMDAR) modulators induce rapid and sustained antidepressant like-activity in rodents through a molecular mechanism of action that involves the activation of Ca2+ dependent signaling pathways. Moreover, ketamine, a global NMDAR antagonist is a potent, novel, and atypical drug that has been successfully used to treat major depressive disorder (MDD). However, because ketamine evokes unwanted side effects, alternative strategies have been developed for the treatment of depression. The objective of the present study was to determine the antidepressant effects of either a single dose of hyperforin or lanicemine vs. their combined effects in mice. Hyperforin modulates intracellular Ca2+ levels by activating Ca2+-conducting non-selective canonical transient receptor potential 6 channel (TRPC6) channels. Lanicemine, on the other hand, blocks NMDARs and regulates Ca2+ dependent processes. To evaluate the antidepressant-like activity of hyperforin and lanicemine, a set of in vivo (behavioral) and in vitro methods (western blotting, Ca2+ imaging studies, electrophysiological, and radioligand binding assays) was employed. Combined administration of hyperforin and lanicemine evoked long-lasting antidepressant-like effects in both naïve and chronic corticosterone-treated mice while also enhancing the expression of the synapsin I, GluA1 subunit, and brain derived neurotrophic factor (BDNF) proteins in the frontal cortex. In Ca2+ imaging studies, lanicemine enhanced Ca2+ influx induced by hyperforin. Moreover, compound such as MK-2206 (Akt kinase inhibitor) inhibited the antidepressant-like activity of hyperforin in the tail suspension test (TST). Hyperforin reversed disturbances induced by MK-801 in the novel object recognition (NOR) test and had no effects on NMDA currents and binding to NMDAR. Our results suggest that co-administration of hyperforin and lanicemine induces long-lasting antidepressant effects in mice and that both substances may have different molecular targets

    Modulation of mitochondrial dysfunction in neurodegenerative diseases via activation of nuclear factor erythroid-2-related factor 2 by food-derived compounds

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    Oxidative stress and mitochondrial dysfunction are early events in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and amyotrophic lateral sclerosis (ALS). Mitochondria are important key players in cellular function based on mitochondrial energy production and their major role in cell physiology. Since neurons are highly depending on mitochondrial energy production due to their high energy demand and their reduced glycolytic capacity mitochondrial dysfunction has fatal consequences for neuronal function and survival. The transcription factor nuclear factor erythroid-2-related factor 2 (Nrf2) is the major regulator of cellular response to oxidative stress. Activation of Nrf2 induces the transcriptional regulation of antioxidant response element (ARE)-dependent expression of a battery of cytoprotective and antioxidant enzymes and proteins. Moreover, activation of Nrf2 protects mitochondria from dysfunction and promotes mitochondrial biogenesis. Therefore, the Nrf2/ARE pathway has become an attractive target for the prevention and treatment of oxidative stress-related neurodegenerative diseases. Small food-derived inducers of the Nrf2/ARE pathway including l-sulforaphane from broccoli and isoliquiritigenin from licorice displayed promising protection of mitochondrial function in models of oxidative stress and neurodegenerative diseases and represent a novel approach to prevent and treat aging-associated neurodegenerative diseases

    Modulation of mitochondrial dysfunction in neurodegenerative diseases via activation of nuclear factor erythroid-2-related factor 2 by food-derived compounds

    No full text
    Oxidative stress and mitochondrial dysfunction are early events in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and amyotrophic lateral sclerosis (ALS). Mitochondria are important key players in cellular function based on mitochondrial energy production and their major role in cell physiology. Since neurons are highly depending on mitochondrial energy production due to their high energy demand and their reduced glycolytic capacity mitochondrial dysfunction has fatal consequences for neuronal function and survival. The transcription factor nuclear factor erythroid-2-related factor 2 (Nrf2) is the major regulator of cellular response to oxidative stress. Activation of Nrf2 induces the transcriptional regulation of antioxidant response element (ARE)-dependent expression of a battery of cytoprotective and antioxidant enzymes and proteins. Moreover, activation of Nrf2 protects mitochondria from dysfunction and promotes mitochondrial biogenesis. Therefore, the Nrf2/ARE pathway has become an attractive target for the prevention and treatment of oxidative stress-related neurodegenerative diseases. Small food-derived inducers of the Nrf2/ARE pathway including l-sulforaphane from broccoli and isoliquiritigenin from licorice displayed promising protection of mitochondrial function in models of oxidative stress and neurodegenerative diseases and represent a novel approach to prevent and treat aging-associated neurodegenerative diseases

    Enhanced Neuroplasticity by the Metabolic Enhancer Piracetam Associated with Improved Mitochondrial Dynamics and Altered Permeability Transition Pore Function

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    The mitochondrial cascade hypothesis of dementia assumes mitochondrial dysfunction leading to reduced energy supply, impaired neuroplasticity, and finally cell death as one major pathomechanism underlying the continuum from brain aging over mild cognitive impairment to initial and advanced late onset Alzheimer’s disease. Accordingly, improving mitochondrial function has become an important strategy to treat the early stages of this continuum. The metabolic enhancer piracetam has been proposed as possible prototype for those compounds by increasing impaired mitochondrial function and related aspects like mechanisms of neuroplasticity. We here report that piracetam at therapeutically relevant concentrations improves neuritogenesis in the human cell line SH-SY5Y over conditions mirroring the whole spectrum of age-associated cognitive decline. These effects go parallel with improvement of impaired mitochondrial dynamics shifting back fission and fusion balance to the energetically more favorable fusion site. Impaired fission and fusion balance can also be induced by a reduction of the mitochondrial permeability transition pore (mPTP) function as atractyloside which indicates the mPTP has similar effects on mitochondrial dynamics. These changes are also reduced by piracetam. These findings suggest the mPTP as an important target for the beneficial effects of piracetam on mitochondrial function

    Enhanced Neuroplasticity by the Metabolic Enhancer Piracetam Associated with Improved Mitochondrial Dynamics and Altered Permeability Transition Pore Function

    Get PDF
    The mitochondrial cascade hypothesis of dementia assumes mitochondrial dysfunction leading to reduced energy supply, impaired neuroplasticity, and finally cell death as one major pathomechanism underlying the continuum from brain aging over mild cognitive impairment to initial and advanced late onset Alzheimer’s disease. Accordingly, improving mitochondrial function has become an important strategy to treat the early stages of this continuum. The metabolic enhancer piracetam has been proposed as possible prototype for those compounds by increasing impaired mitochondrial function and related aspects like mechanisms of neuroplasticity. We here report that piracetam at therapeutically relevant concentrations improves neuritogenesis in the human cell line SH-SY5Y over conditions mirroring the whole spectrum of age-associated cognitive decline. These effects go parallel with improvement of impaired mitochondrial dynamics shifting back fission and fusion balance to the energetically more favorable fusion site. Impaired fission and fusion balance can also be induced by a reduction of the mitochondrial permeability transition pore (mPTP) function as atractyloside which indicates the mPTP has similar effects on mitochondrial dynamics. These changes are also reduced by piracetam. These findings suggest the mPTP as an important target for the beneficial effects of piracetam on mitochondrial function

    Advances in clinical pharmacy education in Germany: a quasi-experimental single-blinded study to evaluate a patient-centred clinical pharmacy course in psychiatry

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    Background The pharmacy profession has shifted towards patient-centred care. To meet the new challenges it is necessary to provide students with clinical competencies. A quasi-experimental single-blinded teaching and learning study was carried out using a parallel-group design to evaluate systematically the benefits of clinical teaching in pharmacy education in Germany. Methods A clinical pharmacy course on a psychiatric ward was developed and implemented for small student groups. The learning aims included: the improvement of patient and interdisciplinary communication skills and the identification and management of pharmaceutical care issues. The control group participated only in the preparation lecture, while the intervention group took part in the complete course. The effects were assessed by an objective structured clinical examination (OSCE) and a student satisfaction survey. Results The intervention group achieved significantly better overall results on the OSCE assessment (46.20 ± 10.01 vs. 26.58 ± 12.91 of a maximum of 90 points; p < 0.0001).The practical tasks had the greatest effect, as reflected in the outcomes of tasks 1–5 (34.94 ± 9.60 vs. 18.63 ± 10.24 of a maximum of 60 points; p < 0.0001). Students’ performance on the theoretical tasks (tasks 6–10) was improved but unsatisfying in both groups considering the maximum score (11.50 ± 4.75 vs. 7.50 ± 4.00 of a maximum of 30 points; p < 0.0001). Of the students, 93% rated the course as practice-orientated, and 90% felt better prepared for patient contact. Many students suggested a permanent implementation and an extension of the course. Conclusions The results suggest that the developed ward-based course provided learning benefits for clinical skills. Students’ perception of the course was positive. Implementation into the regular clinical pharmacy curriculum is therefore advisable
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