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Sample records for bdnf mimetics activate

  1. A BDNF loop-domain mimetic acutely reverses spontaneous apneas and respiratory abnormalities during behavioral arousal in a mouse model of Rett syndrome

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    Miriam Kron

    2014-09-01

    Full Text Available Reduced levels of brain-derived neurotrophic factor (BDNF are thought to contribute to the pathophysiology of Rett syndrome (RTT, a severe neurodevelopmental disorder caused by loss-of-function mutations in the gene encoding methyl-CpG-binding protein 2 (MeCP2. In Mecp2 mutant mice, BDNF deficits have been associated with breathing abnormalities, a core feature of RTT, as well as with synaptic hyperexcitability within the brainstem respiratory network. Application of BDNF can reverse hyperexcitability in acute brainstem slices from Mecp2-null mice, suggesting that therapies targeting BDNF or its receptor, TrkB, could be effective at acute reversal of respiratory abnormalities in RTT. Therefore, we examined the ability of LM22A-4, a small-molecule BDNF loop-domain mimetic and TrkB partial agonist, to modulate synaptic excitability within respiratory cell groups in the brainstem nucleus tractus solitarius (nTS and to acutely reverse abnormalities in breathing at rest and during behavioral arousal in Mecp2 mutants. Patch-clamp recordings in Mecp2-null brainstem slices demonstrated that LM22A-4 decreases excitability at primary afferent synapses in the nTS by reducing the amplitude of evoked excitatory postsynaptic currents and the frequency of spontaneous and miniature excitatory postsynaptic currents. In vivo, acute treatment of Mecp2-null and -heterozygous mutants with LM22A-4 completely eliminated spontaneous apneas in resting animals, without sedation. Moreover, we demonstrate that respiratory dysregulation during behavioral arousal, a feature of human RTT, is also reversed in Mecp2 mutants by acute treatment with LM22A-4. Together, these data support the hypothesis that reduced BDNF signaling and respiratory dysfunction in RTT are linked, and establish the proof-of-concept that treatment with a small-molecule structural mimetic of a BDNF loop domain and a TrkB partial agonist can acutely reverse abnormal breathing at rest and in response to

  2. Definition of a Bidirectional Activity-Dependent Pathway Involving BDNF and Narp

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    Abigail Mariga

    2015-12-01

    Full Text Available One of the cardinal features of neural development and adult plasticity is the contribution of activity-dependent signaling pathways. However, the interrelationships between different activity-dependent genes are not well understood. The immediate early gene neuronal-activity-regulated pentraxin (NPTX2 or Narp encodes a protein that has been associated with excitatory synaptogenesis, AMPA receptor aggregation, and the onset of critical periods. Here, we show that Narp is a direct transcriptional target of brain-derived neurotrophic factor (BDNF, another highly regulated activity-dependent gene involved in synaptic plasticity. Unexpectedly, Narp is bidirectionally regulated by BDNF. Acute BDNF withdrawal results in downregulation of Narp, whereas transcription of Narp is greatly enhanced by BDNF. Furthermore, our results show that BDNF directly regulates Narp to mediate glutamatergic transmission and mossy fiber plasticity. Hence, Narp serves as a significant epistatic target of BDNF to regulate synaptic plasticity during periods of dynamic activity.

  3. Tissue-specific and neural activity-regulated expression of human BDNF gene in BAC transgenic mice

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    Palm Kaia

    2009-06-01

    Full Text Available Abstract Background Brain-derived neurotrophic factor (BDNF is a small secreted protein that has important roles in the developing and adult nervous system. Altered expression or changes in the regulation of the BDNF gene have been implicated in a variety of human nervous system disorders. Although regulation of the rodent BDNF gene has been extensively investigated, in vivo studies regarding the human BDNF gene are largely limited to postmortem analysis. Bacterial artificial chromosome (BAC transgenic mice harboring the human BDNF gene and its regulatory flanking sequences constitute a useful tool for studying human BDNF gene regulation and for identification of therapeutic compounds modulating BDNF expression. Results In this study we have generated and analyzed BAC transgenic mice carrying 168 kb of the human BDNF locus modified such that BDNF coding sequence was replaced with the sequence of a fusion protein consisting of N-terminal BDNF and the enhanced green fluorescent protein (EGFP. The human BDNF-BAC construct containing all BDNF 5' exons preceded by different promoters recapitulated the expression of endogenous BDNF mRNA in the brain and several non-neural tissues of transgenic mice. All different 5' exon-specific BDNF-EGFP alternative transcripts were expressed from the transgenic human BDNF-BAC construct, resembling the expression of endogenous BDNF. Furthermore, BDNF-EGFP mRNA was induced upon treatment with kainic acid in a promotor-specific manner, similarly to that of the endogenous mouse BDNF mRNA. Conclusion Genomic region covering 67 kb of human BDNF gene, 84 kb of upstream and 17 kb of downstream sequences is sufficient to drive tissue-specific and kainic acid-induced expression of the reporter gene in transgenic mice. The pattern of expression of the transgene is highly similar to BDNF gene expression in mouse and human. This is the first study to show that human BDNF gene is regulated by neural activity.

  4. Stress and CRF gate neural activation of BDNF in the mesolimbic reward pathway.

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    Walsh, Jessica J; Friedman, Allyson K; Sun, Haosheng; Heller, Elizabeth A; Ku, Stacy M; Juarez, Barbara; Burnham, Veronica L; Mazei-Robison, Michelle S; Ferguson, Deveroux; Golden, Sam A; Koo, Ja Wook; Chaudhury, Dipesh; Christoffel, Daniel J; Pomeranz, Lisa; Friedman, Jeffrey M; Russo, Scott J; Nestler, Eric J; Han, Ming-Hu

    2014-01-01

    Mechanisms controlling release of brain-derived neurotrophic factor (BDNF) in the mesolimbic dopamine reward pathway remain unknown. We report that phasic optogenetic activation of this pathway increases BDNF amounts in the nucleus accumbens (NAc) of socially stressed mice but not of stress-naive mice. This stress gating of BDNF signaling is mediated by corticotrophin-releasing factor (CRF) acting in the NAc. These results unravel a stress context-detecting function of the brain's mesolimbic circuit.

  5. BDNF heightens the sensitivity of motor neurons to excitotoxic insults through activation of TrkB

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    Hu, Peter; Kalb, Robert G.; Walton, K. D. (Principal Investigator)

    2003-01-01

    The survival promoting and neuroprotective actions of brain-derived neurotrophic factor (BDNF) are well known but under certain circumstances this growth factor can also exacerbate excitotoxic insults to neurons. Prior exploration of the receptor through which BDNF exerts this action on motor neurons deflects attention away from p75. Here we investigated the possibility that BDNF acts through the receptor tyrosine kinase, TrkB, to confer on motor neurons sensitivity to excitotoxic challenge. We blocked BDNF activation of TrkB using a dominant negative TrkB mutant or a TrkB function blocking antibody, and found that this protected motor neurons against excitotoxic insult in cultures of mixed spinal cord neurons. Addition of a function blocking antibody to BDNF to mixed spinal cord neuron cultures is also neuroprotective indicating that endogenously produced BDNF participates in vulnerability to excitotoxicity. We next examined the intracellular signaling cascades that are engaged upon TrkB activation. Previously we found that inhibition of the phosphatidylinositide-3'-kinase (PI3'K) pathway blocks BDNF-induced excitotoxic sensitivity. Here we show that expression of a constitutively active catalytic subunit of PI3'K, p110, confers excitotoxic sensitivity (ES) upon motor neurons not incubated with BDNF. Parallel studies with purified motor neurons confirm that these events are likely to be occuring specifically within motor neurons. The abrogation of BDNF's capacity to accentuate excitotoxic insults may make it a more attractive neuroprotective agent.

  6. BDNF Methylation and Maternal Brain Activity in a Violence-Related Sample.

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    Dominik A Moser

    Full Text Available It is known that increased circulating glucocorticoids in the wake of excessive, chronic, repetitive stress increases anxiety and impairs Brain-Derived Neurotrophic Factor (BDNF signaling. Recent studies of BDNF gene methylation in relation to maternal care have linked high BDNF methylation levels in the blood of adults to lower quality of received maternal care measured via self-report. Yet the specific mechanisms by which these phenomena occur remain to be established. The present study examines the link between methylation of the BDNF gene promoter region and patterns of neural activity that are associated with maternal response to stressful versus non-stressful child stimuli within a sample that includes mothers with interpersonal violence-related PTSD (IPV-PTSD. 46 mothers underwent fMRI. The contrast of neural activity when watching children-including their own-was then correlated to BDNF methylation. Consistent with the existing literature, the present study found that maternal BDNF methylation was associated with higher levels of maternal anxiety and greater childhood exposure to domestic violence. fMRI results showed a positive correlation of BDNF methylation with maternal brain activity in the anterior cingulate (ACC, and ventromedial prefrontal cortex (vmPFC, regions generally credited with a regulatory function toward brain areas that are generating emotions. Furthermore we found a negative correlation of BDNF methylation with the activity of the right hippocampus. Since our stimuli focus on stressful parenting conditions, these data suggest that the correlation between vmPFC/ACC activity and BDNF methylation may be linked to mothers who are at a disadvantage with respect to emotion regulation when facing stressful parenting situations. Overall, this study provides evidence that epigenetic signatures of stress-related genes can be linked to functional brain regions regulating parenting stress, thus advancing our understanding of

  7. Triple-enzyme mimetic activity of nickel-palladium hollow nanoparticles and their application in colorimetric biosensing of glucose.

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    Wang, Qingqing; Zhang, Lingling; Shang, Changshuai; Zhang, Zhiquan; Dong, Shaojun

    2016-04-01

    We demonstrate that nickel-palladium hollow nanoparticles (NiPd hNPs) exhibit triple-enzyme mimetic activity: oxidase-like activity, peroxidase-like activity and catalase-like activity. As peroxidase mimetics, the catalytic activity of NiPd hNPs was investigated in detail. On this basis, a simple glucose biosensor with a wide linear range and low detection limit was developed. PMID:27009927

  8. Deltamethrin, a type II pyrethroid insecticide, has neurotrophic effects on neurons with continuous activation of the Bdnf promoter.

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    Ihara, Daisuke; Fukuchi, Mamoru; Honma, Daisuke; Takasaki, Ichiro; Ishikawa, Mitsuru; Tabuchi, Akiko; Tsuda, Masaaki

    2012-02-01

    Pyrethroids, widely used insecticides with low acute toxicity in mammals, affect sodium channels in neurons. In a primary culture of rat cortical neurons, deltamethrin (DM), a type II pyrethroid, markedly enhanced the expression of brain-derived neurotrophic factor (BDNF) exon IV-IX (Bdnf eIV-IX) mRNA. In this study, we found that DM has a neurotrophic effect on cultured neurons and investigated the mechanisms responsible for it. One μM DM increased cell survival, neurite complexity and length. Neurite complexity and length were reduced not only by a blockade of cellular excitation with GABA or Ca(2+) influx via L-type voltage-dependent calcium channels with nicardipine, but also by a blockade of TrkB, a specific receptor for BDNF, with TrkB/Fc. These data indicate DM has neurotrophic actions. DM-induced Bdnf eIV-IX mRNA expression through the calcineurin and ERK/MAPK pathways, the increase of which was reduced by GABA(A) receptor activation. Using a promoter assay, we found that Ca(2+)-responsive elements including a CRE are involved in the DM-induced activation of the Bdnf promoter IV (Bdnf-pIV). The intracellular concentration of Ca(2+) and activation of Bdnf-pIV remained elevated for, at least, 1 and 24 h, respectively. Moreover, GABA(A) receptor activation or a blockade of Ca(2+) influx even after starting the incubation with DM reduced the elevated activity of Bdnf-pIV. These data demonstrated that the prolonged activation of Bdnf-pIV occurred because of this continuous increase in the intracellular Ca(2+) concentration. Thus, DM has neurotrophic effects on neurons, likely due to prolonged activation of Bdnf promoter in neurons. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.

  9. Activity of potent and selective host defense peptide mimetics in mouse models of oral candidiasis.

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    Ryan, Lisa K; Freeman, Katie B; Masso-Silva, Jorge A; Falkovsky, Klaudia; Aloyouny, Ashwag; Markowitz, Kenneth; Hise, Amy G; Fatahzadeh, Mahnaz; Scott, Richard W; Diamond, Gill

    2014-07-01

    There is a strong need for new broadly active antifungal agents for the treatment of oral candidiasis that not only are active against many species of Candida, including drug-resistant strains, but also evade microbial countermeasures which may lead to resistance. Host defense peptides (HDPs) can provide a foundation for the development of such agents. Toward this end, we have developed fully synthetic, small-molecule, nonpeptide mimetics of the HDPs that improve safety and other pharmaceutical properties. Here we describe the identification of several HDP mimetics that are broadly active against C. albicans and other species of Candida, rapidly fungicidal, and active against yeast and hyphal cultures and that exhibit low cytotoxicity for mammalian cells. Importantly, specificity for Candida over commensal bacteria was also evident, thereby minimizing potential damage to the endogenous microbiome which otherwise could favor fungal overgrowth. Three compounds were tested as topical agents in two different mouse models of oral candidiasis and were found to be highly active. Following single-dose administrations, total Candida burdens in tongues of infected animals were reduced up to three logs. These studies highlight the potential of HDP mimetics as a new tool in the antifungal arsenal for the treatment of oral candidiasis.

  10. Role of phosphate on stability and catalase mimetic activity of cerium oxide nanoparticles.

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    Singh, Ragini; Singh, Sanjay

    2015-08-01

    Cerium oxide nanoparticles (CeNPs) have been recently shown to scavenge reactive oxygen and nitrogen species (ROS and RNS) in different experimental model systems. CeNPs (3+) and CeNPs (4+) have been shown to exhibit superoxide dismutase (SOD) and catalase mimetic activity, respectively. Due to their nanoscale dimension, CeNPs are expected to interact with the components of biologically relevant buffers and medium, which could alter their catalytic properties. We have demonstrated earlier that CeNPs (3+) interact with phosphate and lose the SOD activity. However, very little is known about the interaction of CeNPs (4+) with the phosphate and other anions, predominantly present in biological buffers and their effects on the catalase mimetic-activity of these nanoparticles. In this study, we report that catalase mimetic-activity of CeNPs (4+) is resistant to the phosphate anions, pH changes and composition of cell culture media. Given the abundance of phosphate anions in the biological system, it is likely that internalized CeNPs would be influenced by cytoplasmic and nucleoplasmic concentration of phosphate.

  11. Endowing Single-Chain Polymer Nanoparticles with Enzyme-Mimetic Activity

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    Perez-Baena, Irma; Barroso-Bujans, Fabienne; Gasser, Urs; Arbe, Arantxa; Moreno Segurado, Ángel J.; Colmenero de León, Juan; Pomposo, José A.

    2013-01-01

    The development of simple, efficient, and robust strategies affording the facile construction of biomimetic organocatalytic nano-objects is currently a subject of great interest. Herein, a new pathway to artificial organocatalysts based on partially collapsed individual soft nano-objects displaying useful and diverse biomimetic catalytic functions is reported. Single-chain polymer nanoparticles endowed with enzyme-mimetic activity synthesized following this new route display (i) a relatively ...

  12. BDNF selectively regulates GABAA receptor transcription by activation of the JAK/STAT pathway.

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    Lund, Ingrid V; Hu, Yinghui; Raol, YogendraSinh H; Benham, Rebecca S; Faris, Ramona; Russek, Shelley J; Brooks-Kayal, Amy R

    2008-01-01

    The gamma-aminobutyric acid (GABA) type A receptor (GABA(A)R) is the major inhibitory neurotransmitter receptor in the brain. Its multiple subunits show regional, developmental, and disease-related plasticity of expression; however, the regulatory networks controlling GABA(A)R subunit expression remain poorly understood. We report that the seizure-induced decrease in GABA(A)R alpha1 subunit expression associated with epilepsy is mediated by the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway regulated by brain-derived neurotrophic factor (BDNF). BDNF- and seizure-dependent phosphorylation of STAT3 cause the adenosine 3',5'-monophosphate (cAMP) response element-binding protein (CREB) family member ICER (inducible cAMP early repressor) to bind with phosphorylated CREB at the Gabra1:CRE site. JAK/STAT pathway inhibition prevents the seizure-induced decrease in GABA(A)R alpha1 abundance in vivo and, given that BDNF is known to increase the abundance of GABA(A)R alpha4 in a JAK/STAT-independent manner, indicates that BDNF acts through at least two distinct pathways to influence GABA(A)R-dependent synaptic inhibition. PMID:18922788

  13. The BDNF Val66Met Polymorphism Influences Reading Ability and Patterns of Neural Activation in Children.

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    Jasińska, Kaja K; Molfese, Peter J; Kornilov, Sergey A; Mencl, W Einar; Frost, Stephen J; Lee, Maria; Pugh, Kenneth R; Grigorenko, Elena L; Landi, Nicole

    2016-01-01

    Understanding how genes impact the brain's functional activation for learning and cognition during development remains limited. We asked whether a common genetic variant in the BDNF gene (the Val66Met polymorphism) modulates neural activation in the young brain during a critical period for the emergence and maturation of the neural circuitry for reading. In animal models, the bdnf variation has been shown to be associated with the structure and function of the developing brain and in humans it has been associated with multiple aspects of cognition, particularly memory, which are relevant for the development of skilled reading. Yet, little is known about the impact of the Val66Met polymorphism on functional brain activation in development, either in animal models or in humans. Here, we examined whether the BDNF Val66Met polymorphism (dbSNP rs6265) is associated with children's (age 6-10) neural activation patterns during a reading task (n = 81) using functional magnetic resonance imaging (fMRI), genotyping, and standardized behavioral assessments of cognitive and reading development. Children homozygous for the Val allele at the SNP rs6265 of the BDNF gene outperformed Met allele carriers on reading comprehension and phonological memory, tasks that have a strong memory component. Consistent with these behavioral findings, Met allele carriers showed greater activation in reading-related brain regions including the fusiform gyrus, the left inferior frontal gyrus and left superior temporal gyrus as well as greater activation in the hippocampus during a word and pseudoword reading task. Increased engagement of memory and spoken language regions for Met allele carriers relative to Val/Val homozygotes during reading suggests that Met carriers have to exert greater effort required to retrieve phonological codes. PMID:27551971

  14. Effects of BDNF polymorphism and physical activity on episodic memory in the elderly: a cross sectional study

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    Canivet, Anne; Albinet, Cédric T.; André, Nathalie; Pylouster, Jean; Rodríguez-Ballesteros, Montserrat; Kitzis, Alain; Audiffren, Michel

    2015-01-01

    Background The brain-derived neurotrophic factor (BDNF) concentration is highest in the hippocampus compared with that in other brain structures and affects episodic memory, a cognitive function that is impaired in older adults. According to the neurotrophic hypothesis, BDNF released during physical activity enhances brain plasticity and consequently brain health. However, even if the physical activity level is involved in the secretion of neurotrophin, this protein is also under the control ...

  15. Activity of antimicrobial peptide mimetics in the oral cavity: I. Activity against biofilms of Candida albicans.

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    Hua, J; Yamarthy, R; Felsenstein, S; Scott, R W; Markowitz, K; Diamond, G

    2010-12-01

    Naturally occurring antimicrobial peptides hold promise as therapeutic agents against oral pathogens such as Candida albicans but numerous difficulties have slowed their development. Synthetic, non-peptidic analogs that mimic the properties of these peptides have many advantages and exhibit potent, selective antimicrobial activity. Several series of mimetics (with molecular weight oral Candida strains as a proof-of-principle for their antifungal properties. One phenylalkyne and several arylamide compounds with reduced mammalian cytotoxicities were found to be active against C. albicans. These compounds demonstrated rapid fungicidal activity in liquid culture even in the presence of saliva, and demonstrated synergy with standard antifungal agents. When assayed against biofilms grown on denture acrylic, the compounds exhibited potent fungicidal activity as measured by metabolic and fluorescent viability assays. Repeated passages in sub-minimum inhibitory concentration levels did not lead to resistant Candida, in contrast to fluconazole. Our results demonstrate the proof-of principle for the use of these compounds as anti-Candida agents, and their further testing is warranted as novel anti-Candida therapies.

  16. Functional and structural specific roles of activity-driven BDNF within circuits formed by single spiny stellate neurons of the barrel cortex

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    Qian-Quan eSun

    2014-11-01

    Full Text Available Brain derived neurotrophic factor (BDNF plays key roles in several neurodevelopmental disorders and actions of pharmacological treatments. However it is uncealr how specific BDNF’s effects are on diffeerent circuit components. Current studies have largely focused on the role of BDNF in modification of synaptic development. The precise roles of BDNF in the refinement of a functional circuit in vivo remain unclear. Val66Met polymorphism of BDNF may be associated with increased risk for cognitive impairments and is mediated at least in part by activity-dependent trafficking and/or secretion of BDNF. Using mutant mice that lacked activity-driven BDNF expression (bdnf-KIV, we previously reported that experience regulation of the cortical GABAergic network is mediated by activity-driven BDNF expression. Here, we demonstrate that activity-driven BDNF’s effects on circuits formed by the layer IV spiny stellate cells are highly specific. Structurally, dendritic but not axonal morphology was altered in the mutant. Physiologically, GABAergic but not glutamatergic synapses were severely affected. The effects on GABA transmission occurs via presynaptic alteration of calcium-dependent release probability. These results suggest that neuronal activity through activity-driven BDNF expression, can selectively regulate specific features of layer IV circuits in vivo. We postulate that the role of activity-dependent BDNF is to modulate the computational ability of circuits that relate to the gain control (i.e. feed-forward inhibition; whereas the basic wiring of circuits relevant to the sensory pathway is spared. Gain control modulation within cortical circuits has broad impact on cognitive processing and brain state-transitions. Cognitive behavior and mode is determined by brain states, thus the studying of circuit alteration by endogenous BDNF provides insights into the cellular and molecular mechanisms of diseases mediated by BDNF.

  17. Synaptic network activity induces neuronal differentiation of adult hippocampal precursor cells through BDNF signaling

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    Harish Babu

    2009-09-01

    Full Text Available Adult hippocampal neurogenesis is regulated by activity. But how do neural precursor cells in the hippocampus respond to surrounding network activity and translate increased neural activity into a developmental program? Here we show that long-term potential (LTP-like synaptic activity within a cellular network of mature hippocampal neurons promotes neuronal differentiation of newly generated cells. In co-cultures of precursor cells with primary hippocampal neurons, LTP-like synaptic plasticity induced by addition of glycine in Mg2+-free media for 5 min, produced synchronous network activity and subsequently increased synaptic strength between neurons. Furthermore, this synchronous network activity led to a significant increase in neuronal differentiation from the co-cultured neural precursor cells. When applied directly to precursor cells, glycine and Mg2+-free solution did not induce neuronal differentiation. Synaptic plasticity-induced neuronal differentiation of precursor cells was observed in the presence of GABAergic neurotransmission blockers but was dependent on NMDA-mediated Ca2+ influx. Most importantly, neuronal differentiation required the release of brain-derived neurotrophic factor (BDNF from the underlying substrate hippocampal neurons as well as TrkB receptor phosphorylation in precursor cells. This suggests that activity-dependent stem cell differentiation within the hippocampal network is mediated via synaptically evoked BDNF signaling.

  18. Histone deacetylase activity and brain-derived neurotrophic factor (BDNF levels in a pharmacological model of mania

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    Laura Stertz

    2014-03-01

    Full Text Available Objective: In the present study, we aimed to examine the effects of repeated D-amphetamine (AMPH exposure, a well-accepted animal model of acute mania in bipolar disorder (BD, and histone deacetylase (HDAC inhibitors on locomotor behavior and HDAC activity in the prefrontal cortex (PFC and peripheral blood mononuclear cells (PBMCs of rats. Moreover, we aimed to assess brain-derived neurotrophic factor (BDNF protein and mRNA levels in these samples. Methods: We treated adult male Wistar rats with 2 mg/kg AMPH or saline intraperitoneally for 14 days. Between the 8th and 14th days, rats also received 47.5 mg/kg lithium (Li, 200 mg/kg sodium valproate (VPT, 2 mg/kg sodium butyrate (SB, or saline. We evaluated locomotor activity in the open-field task and assessed HDAC activity in the PFC and PBMCs, and BDNF levels in the PFC and plasma. Results: AMPH significantly increased locomotor activity, which was reversed by all drugs. This hyperactivity was associated with increased HDAC activity in the PFC, which was partially reversed by Li, VPT, and SB. No differences were found in BDNF levels. Conclusion: Repeated AMPH administration increases HDAC activity in the PFC without altering BDNF levels. The partial reversal of HDAC increase by Li, VPT, and SB may account for their ability to reverse AMPH-induced hyperactivity.

  19. BDNF Methylation and Maternal Brain Activity in a Violence-Related Sample

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    Moser, Dominik A.; Ariane Paoloni-Giacobino; Ludwig Stenz; Wafae Adouan; Aurélia Manini; Francesca Suardi; Cordero, Maria I.; Marylene Vital; Ana Sancho Rossignol; Sandra Rusconi-Serpa; François Ansermet; Dayer, Alexandre G.; Schechter, Daniel S.

    2015-01-01

    It is known that increased circulating glucocorticoids in the wake of excessive, chronic, repetitive stress increases anxiety and impairs Brain-Derived Neurotrophic Factor (BDNF) signaling. Recent studies of BDNF gene methylation in relation to maternal care have linked high BDNF methylation levels in the blood of adults to lower quality of received maternal care measured via self-report. Yet the specific mechanisms by which these phenomena occur remain to be established. The present study ex...

  20. Activation of the cAMP Pathway Induces RACK1-Dependent Binding of β-Actin to BDNF Promoter

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    Neasta, Jeremie; Fiorenza, Anna; He, Dao-Yao; Phamluong, Khanhky; Kiely, Patrick A.; Ron, Dorit

    2016-01-01

    RACK1 is a scaffolding protein that contributes to the specificity and propagation of several signaling cascades including the cAMP pathway. As such, RACK1 participates in numerous cellular functions ranging from cell migration and morphology to gene transcription. To obtain further insights on the mechanisms whereby RACK1 regulates cAMP-dependent processes, we set out to identify new binding partners of RACK1 during activation of the cAMP signaling using a proteomics strategy. We identified β-actin as a direct RACK1 binding partner and found that the association between β-actin and RACK1 is increased in response to the activation of the cAMP pathway. Furthermore, we show that cAMP-dependent increase in BDNF expression requires filamentous actin. We further report that β-actin associates with the BDNF promoter IV upon the activation of the cAMP pathway and present data to suggest that the association of β-actin with BDNF promoter IV is RACK1-dependent. Taken together, our data suggest that β-actin is a new RACK1 binding partner and that the RACK1 and β-actin association participate in the cAMP-dependent regulation of BDNF transcription. PMID:27505161

  1. An apoA-I mimetic peptide increases LCAT activity in mice through increasing HDL concentration

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    Xun Chen, Charlotte Burton, Xuelei Song, Lesley Mcnamara, Annunziata Langella, Simona Cianetti, Ching H. Chang, Jun Wang

    2009-01-01

    Full Text Available Lecithin cholesterol acyltransferase (LCAT plays a key role in the reverse cholesterol transport (RCT process by converting cholesterol to cholesteryl ester to form mature HDL particles, which in turn deliver cholesterol back to the liver for excretion and catabolism. HDL levels in human plasma are negatively correlated with cardiovascular risk and HDL functions are believed to be more important in atheroprotection. This study investigates whether and how D-4F, an apolipoprotein A-I (apoA-I mimetic peptide, influences LCAT activity in the completion of the RCT process. We demonstrated that the apparent rate constant value of the LCAT enzyme reaction gives a measure of LCAT activity and determined the effects of free metals and a reducing agent on LCAT activity, showing an inhibition hierarchy of Zn2+>Mg2+>Ca2+ and no inhibition with β-mercaptoethanol up to 10 mM. We reconstituted nano-disc particles using apoA-I or D-4F with phospholipids. These particles elicited good activity in vitro in the stimulation of cholesterol efflux from macrophages through the ATP-binding cassette transporter A1 (ABCA1. With these particles we studied the LCAT activity and demonstrated that D-4F did not activate LCAT in vitro. Furthermore, we have done in vivo experiments with apoE-null mice and demonstrated that D-4F (20 mg/kg body weight, once daily subcutaneously increased LCAT activity and HDL level as well as apoA-I concentration at 72 hours post initial dosing. Finally, we have established a correlation between HDL concentration and LCAT activity in the D-4F treated mice.

  2. An investigation of the mimetic enzyme activity of two-dimensional Pd-based nanostructures

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    Wei, Jingping; Chen, Xiaolan; Shi, Saige; Mo, Shiguang; Zheng, Nanfeng

    2015-11-01

    In this work, we investigated the mimetic enzyme activity of two-dimensional (2D) Pd-based nanostructures (e.g. Pd nanosheets, Pd@Au and Pd@Pt nanoplates) and found that they possess intrinsic peroxidase-, oxidase- and catalase-like activities. These nanostructures were able to activate hydrogen peroxide or dissolved oxygen for catalyzing the oxidation of organic substrates, and decompose hydrogen peroxide to generate oxygen. More systematic investigations revealed that the peroxidase-like activities of these Pd-based nanomaterials were highly structure- and composition-dependent. Among them, Pd@Pt nanoplates displayed the highest peroxidase-like activity. Based on these findings, Pd-based nanostructures were applied for the colorimetric detection of H2O2 and glucose, and also the electro-catalytic reduction of H2O2. This work offers a promising prospect for the application of 2D noble metal nanostructures in biocatalysis.In this work, we investigated the mimetic enzyme activity of two-dimensional (2D) Pd-based nanostructures (e.g. Pd nanosheets, Pd@Au and Pd@Pt nanoplates) and found that they possess intrinsic peroxidase-, oxidase- and catalase-like activities. These nanostructures were able to activate hydrogen peroxide or dissolved oxygen for catalyzing the oxidation of organic substrates, and decompose hydrogen peroxide to generate oxygen. More systematic investigations revealed that the peroxidase-like activities of these Pd-based nanomaterials were highly structure- and composition-dependent. Among them, Pd@Pt nanoplates displayed the highest peroxidase-like activity. Based on these findings, Pd-based nanostructures were applied for the colorimetric detection of H2O2 and glucose, and also the electro-catalytic reduction of H2O2. This work offers a promising prospect for the application of 2D noble metal nanostructures in biocatalysis. Electronic supplementary information (ESI) available: TEM images, EDX and dispersion stability of Pd-based nanomaterials

  3. Leukocyte mimetic polysaccharide microparticles tracked in vivo on activated endothelium and in abdominal aortic aneurysm.

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    Bonnard, Thomas; Serfaty, Jean-Michel; Journé, Clément; Ho Tin Noe, Benoît; Arnaud, Denis; Louedec, Liliane; Derkaoui, Sidi Mohammed; Letourneur, Didier; Chauvierre, Cédric; Le Visage, Catherine

    2014-08-01

    We have developed injectable microparticles functionalized with fucoidan, in which sulfated groups mimic the anchor sites of P-selectin glycoprotein ligand-1 (PSGL-1), one of the principal receptors supporting leukocyte adhesion. These targeted microparticles were combined with a fluorescent dye and a T2(∗) magnetic resonance imaging (MRI) contrast agent, and then tracked in vivo with small animal imaging methods. Microparticles of 2.5μm were obtained by a water-in-oil emulsification combined with a cross-linking process of polysaccharide dextran, fluorescein isothiocyanate dextran, pullulan and fucoidan mixed with ultrasmall superparamagnetic particles of iron oxide. Fluorescent intravital microscopy observation revealed dynamic adsorption and a leukocyte-like behaviour of fucoidan-functionalized microparticles on a calcium ionophore induced an activated endothelial layer of a mouse mesentery vessel. We observed 20times more adherent microparticles on the activated endothelium area after the injection of functionalized microparticles compared to non-functionalized microparticles (197±11 vs. 10±2). This imaging tool was then applied to rats presenting an elastase perfusion model of abdominal aortic aneurysm (AAA) and 7.4T in vivo MRI was performed. Visual analysis of T2(∗)-weighted MR images showed a significant contrast enhancement on the inner wall of the aneurysm from 30min to 2h after the injection. Histological analysis of AAA cryosections revealed microparticles localized inside the aneurysm wall, in the same areas in which immunostaining shows P-selectin expression. The developed leukocyte mimetic imaging tool could therefore be relevant for molecular imaging of vascular diseases and for monitoring biologically active areas prone to rupture in AAA. PMID:24769117

  4. Activation of concurrent apoptosis and necroptosis by SMAC mimetics for the treatment of refractory and relapsed ALL.

    Science.gov (United States)

    McComb, Scott; Aguadé-Gorgorió, Júlia; Harder, Lena; Marovca, Blerim; Cario, Gunnar; Eckert, Cornelia; Schrappe, Martin; Stanulla, Martin; von Stackelberg, Arend; Bourquin, Jean-Pierre; Bornhauser, Beat C

    2016-05-18

    More precise treatment strategies are urgently needed to decrease toxicity and improve outcomes for treatment-refractory leukemia. We used ex vivo drug response profiling of high-risk, relapsed, or refractory acute lymphoblastic leukemia (ALL) cases and identified a subset with exquisite sensitivity to small-molecule mimetics of the second mitochondria-derived activator of caspases (SMAC) protein. Potent ex vivo activity of the SMAC mimetic (SM) birinapant correlated with marked in vivo antileukemic effects, as indicated by delayed engraftment, decreased leukemia burden, and prolonged survival of xenografted mice. Antileukemic activity was dependent on simultaneous execution of apoptosis and necroptosis, as demonstrated by functional genomic dissection with a multicolored lentiCRISPR approach to simultaneously disrupt multiple genes in patient-derived ALL. SM specifically targeted receptor-interacting protein kinase 1 (RIP1)-dependent death, and CRISPR-mediated disruption of RIP1 completely blocked SM-induced death yet had no impact on the response to standard antileukemic agents. Thus, SM compounds such as birinapant circumvent escape from apoptosis in leukemia by activating a potent dual RIP1-dependent apoptotic and necroptotic cell death, which is not exploited by current therapy. Ex vivo drug activity profiling could provide important functional diagnostic information to identify patients who may benefit from targeted treatment with birinapant in early clinical trials. PMID:27194728

  5. Influence of Block Copolymerization on the Antifreeze Protein Mimetic Ice Recrystallization Inhibition Activity of Poly(vinyl alcohol).

    Science.gov (United States)

    Congdon, Thomas R; Notman, Rebecca; Gibson, Matthew I

    2016-09-12

    Antifreeze (glyco) proteins are produced by many cold-acclimatized species to enable them to survive subzero temperatures. These proteins have multiple macroscopic effects on ice crystal growth which makes them appealing for low-temperature applications-from cellular cryopreservation to food storage. Poly(vinyl alcohol) has remarkable ice recrystallization inhibition activity, but its mode of action is uncertain as is the extent at which it can be incorporated into other high-order structures. Here the synthesis and characterization of well-defined block copolymers containing poly(vinyl alcohol) and poly(vinylpyrrolidone) by RAFT/MADIX polymerization is reported, as new antifreeze protein mimetics. The effect of adding a large second hydrophilic block is studied across a range of compositions, and it is found to be a passive component in ice recrystallization inhibition assays, enabling retention of all activity. In the extreme case, a block copolymer with only 10% poly(vinyl alcohol) was found to retain all activity, where statistical copolymers of PVA lose all activity with very minor changes to composition. These findings present a new method to increase the complexity of antifreeze protein mimetic materials, while retaining activity, and also to help understand the underlying mechanisms of action.

  6. Smac mimetic SM-164 potentiates APO2L/TRAIL- and doxorubicin-mediated anticancer activity in human hepatocellular carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Shuijun Zhang

    Full Text Available BACKGROUND: The members of inhibitor of apoptosis proteins (IAPs family are key negative regulators of apoptosis. Overexpression of IAPs are found in hepatocellular carcinoma (HCC, and can contribute to chemotherapy resistance and recurrence of HCC. Small-molecule Second mitochondria-derived activator of caspases (Smac mimetics have recently emerged as novel anticancer drugs through targeting IAPs. The specific aims of this study were to 1 examine the anticancer activity of Smac mimetics as a single agent and in combination with chemotherapy in HCC cells, and 2 investigate the mechanism of anticancer action of Smac mimetics. METHODS: Four HCC cell lines, including SMMC-7721, BEL-7402, HepG2 and Hep3B, and 12 primary HCC cells were used in this study. Smac mimetic SM-164 was used to treat HCC cells. Cell viability, cell death induction and clonal formation assays were used to evaluate the anticancer activity. Western blotting analysis and a pancaspase inhibitor were used to investigate the mechanisms. RESULTS: Although SM-164 induced complete cIAP-1 degradation, it displayed weak inhibitory effects on the viability of HCC cells. Nevertheless, SM-164 considerably potentiated Apo2 ligand or TNF-related apoptosis-inducing ligand (APO2L/TRAIL- and Doxorubicin-mediated anticancer activity in HCC cells. Mechanistic studies demonstrated that SM-164 in combination with chemotherapeutic agents resulted in enhanced activation of caspases-9, -3 and cleavage of poly ADP-ribose polymerase (PARP, and also led to decreased AKT activation. CONCLUSIONS: Smac mimetics can enhance chemotherapeutic-mediated anticancer activity by enhancing apoptosis signaling and suppressing survival signaling in HCC cells. This study suggests Smac mimetics are potential therapeutic agents for HCC.

  7. Structure-Activity Studies of Brassinosteroids and the Search for Novel Analogues and Mimetics with Improved Bioactivity.

    Science.gov (United States)

    Back, Thomas G.; Pharis, Richard P.

    2003-12-01

    A number of novel brassinosteroid analogues were synthesized and subjected to the rice leaf lamina inclination bioassay. Modified B-ring analogues included lactam, thiolactone, cyclic ether, ketone, hydroxyl, and exocyclic methylene derivatives of brassinolide. Those derivatives containing polar functional groups retained considerable bioactivity, whereas the exocyclic methylene compounds were devoid of activity. Analogues containing normal alkyl and cycloalkyl substituents at C-24 (in place of the isopropyl group of brassinolide) showed an inverse relationship between activity and chain length or ring size, respectively. The corresponding cyclopropyl and cyclobutyl derivatives were significantly more active than brassinolide and appear to be the most potent brassinosteroids reported to date. When synergized with the auxin indole-3-acetic acid (IAA), their bioactivity can be further enhanced by 1-2 orders of magnitude. The cyclopropyl derivative, when coapplied with the auxin naphthaleneacetic acid, gave a significant increase in yield of wheat in a field trial. Certain 25- and 26-hydroxy derivatives are known metabolites of brassinosteroids. All of the C-25 stereoisomers of 25-hydroxy, 26-hydroxy, and 25,26-dihydroxy derivatives of brassinolide were prepared and shown to be much less active than brassinolide. This indicates that they are likely metabolic deactivation products of the parent phytohormone. A series of methyl ethers of brassinolide was synthesized to block deactivation by glucosylation of the free hydroxyl groups. The most significant finding was that the compound where three of the four hydroxyl groups (at C-3, C-22, and C-23) had been converted to methyl ethers retained substantial bioactivity. This type of modification could, in theory, allow brassinolide or 24-epibrassinolide to resist deactivation and thus offer greater persistence in field applications. A series of nonsteroidal mimetics of brassinolide was designed and synthesized. Two of the

  8. Detection of Hg2+ based on the selective inhibition of peroxidase mimetic activity of BSA-Au clusters.

    Science.gov (United States)

    Zhu, Rui; Zhou, Yan; Wang, Xi-Liang; Liang, Li-Ping; Long, Yi-Juan; Wang, Qin-Long; Zhang, Hai-Jie; Huang, Xiao-Xiao; Zheng, Hu-Zhi

    2013-12-15

    It was found that Hg(2+) can inhibit the peroxidase mimetic activity of bovine serum albumin (BSA) protected Au clusters (BSA-Au) due to the specific interaction between Hg(2+) and Au(+) existed onto the surface of BSA-Au clusters. By coupling with 3, 3', 5, 5'-tetramethylbenzidine (TMB)-H2O2 chromogenic reaction, a novel method for Hg(2+) detection was developed based on the inhibiting effect of Hg(2+) on BSA-Au clusters peroxidase-like activity. This method exhibited high selectivity and sensitivity. As low as 3 nM (0.6 ppb, 3σ) Hg(2+) could be detected with a linear range from 10 nM (2 ppb) to 10 µM (2 ppm) and this method was successfully applied for the determination of total mercury content in skin lightening products.

  9. Tissue-type plasminogen activator-plasmin-BDNF modulate glutamate-induced phase-shifts of the mouse suprachiasmatic circadian clock in vitro.

    Science.gov (United States)

    Mou, Xiang; Peterson, Cynthia B; Prosser, Rebecca A

    2009-10-01

    The mammalian circadian clock in the suprachiasmatic nucleus (SCN) maintains environmental synchrony through light signals transmitted by glutamate released from retinal ganglion terminals. Brain-derived neurotrophic factor (BDNF) is required for light/glutamate to reset the clock. In the hippocampus, BDNF is activated by the extracellular protease, plasmin, which is produced from plasminogen by tissue-type plasminogen activator (tPA). We provide data showing expression of proteins from the plasminogen activation cascade in the SCN and their involvement in circadian clock phase-resetting. Early night glutamate application to SCN-containing brain slices resets the circadian clock. Plasminogen activator inhibitor-1 (PAI-1) blocked these shifts in slices from wild-type mice but not mice lacking its stabilizing protein, vitronectin (VN). Plasmin, but not plasminogen, prevented inhibition by PAI-1. Both plasmin and active BDNF reversed alpha(2)-antiplasmin inhibition of glutamate-induced shifts. alpha(2)-Antiplasmin decreased the conversion of inactive to active BDNF in the SCN. Finally, both tPA and BDNF allowed daytime glutamate-induced phase-resetting. Together, these data are the first to demonstrate expression of these proteases in the SCN, their involvement in modulating photic phase-shifts, and their activation of BDNF in the SCN, a potential 'gating' mechanism for photic phase-resetting. These data also demonstrate a functional interaction between PAI-1 and VN in adult brain. Given the usual association of these proteins with the extracellular matrix, these data suggest new lines of investigation into the locations and processes modulating mammalian circadian clock phase-resetting.

  10. Alterations in grooming activity and syntax in heterozygous SERT and BDNF knockout mice: the utility of behavior-recognition tools to characterize mutant mouse phenotypes.

    Science.gov (United States)

    Kyzar, Evan J; Pham, Mimi; Roth, Andrew; Cachat, Jonathan; Green, Jeremy; Gaikwad, Siddharth; Kalueff, Allan V

    2012-12-01

    Serotonin transporter (SERT) and brain-derived neurotrophic factor (BDNF) are key modulators of molecular signaling, cognition and behavior. Although SERT and BDNF mutant mouse phenotypes have been extensively characterized, little is known about their self-grooming behavior. Grooming represents an important behavioral domain sensitive to environmental stimuli and is increasingly used as a model for repetitive behavioral syndromes, such as autism and attention deficit/hyperactivity disorder. The present study used heterozygous ((+/-)) SERT and BDNF male mutant mice on a C57BL/6J background and assessed their spontaneous self-grooming behavior applying both manual and automated techniques. Overall, SERT(+/-) mice displayed a general increase in grooming behavior, as indicated by more grooming bouts and more transitions between specific grooming stages. SERT(+/-) mice also aborted more grooming bouts, but showed generally unaltered activity levels in the observation chamber. In contrast, BDNF(+/-) mice displayed a global reduction in grooming activity, with fewer bouts and transitions between specific grooming stages, altered grooming syntax, as well as hypolocomotion and increased turning behavior. Finally, grooming data collected by manual and automated methods (HomeCageScan) significantly correlated in our experiments, confirming the utility of automated high-throughput quantification of grooming behaviors in various genetic mouse models with increased or decreased grooming phenotypes. Taken together, these findings indicate that mouse self-grooming behavior is a reliable behavioral biomarker of genetic deficits in SERT and BDNF pathways, and can be reliably measured using automated behavior-recognition technology.

  11. Topiramate protects against glutamate excitotoxicity via activating BDNF/TrkB-dependent ERK pathway in rodent hippocampal neurons.

    Science.gov (United States)

    Mao, Xiao-Yuan; Cao, Yong-Gang; Ji, Zhong; Zhou, Hong-Hao; Liu, Zhao-Qian; Sun, Hong-Li

    2015-07-01

    Topiramate (TPM) was previously found to have neuroprotection against neuronal injury in epileptic and ischemic models. However, whether TPM protects against glutamate-induced excitotoxicity in hippocampal neurons is elusive. Our present work aimed to evaluate the protective effect of TPM against glutamate toxicity in hippocampal neurons and further figure out the potential molecular mechanisms. The in vitro glutamate excitotoxic model was prepared with 125μM glutamate for 20min. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) analysis and Hoechst 33342 staining were conducted to detect neuronal survival. The protein expressions of brain-derived neurotrophic factor (BDNF), TrkB, mitogen-activated protein kinase (MAPK) cascade (including extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 MAPK), cyclic AMP response element binding protein (CREB), Bcl-2, Bax and β-actin were detected via Western blot assay. Our results demonstrated that TPM protected hippocampal neurons from glutamate toxicity. Meanwhile, the pretreatment of TPM for 10min significantly prevented the down-regulation of BDNF and the phosphorylation of TrkB. Furthermore, the elevation of phosphorylated EKR expression was significantly inhibited after blockade of TrkB by TrkB IgG, while no alterations of phosphorylated JNK and p38 MAPK were found in the cultured hippocampal neurons. Besides, it was also found that the enhanced phosphorylation of CREB was evidently reversed under excitotoxic conditions after treating with U0126 (the selective inhibitor of ERK). The protein level of Bcl-2 was also observed to be remarkably increased after TPM treatment. In conclusion, these findings implicate that TPM exerts neuroprotective effects against glutamate excitotoxicity in hippocampal neurons and its protection may be modulated through BDNF/TrkB-dependent ERK pathway.

  12. Targeting p38 or MK2 Enhances the Anti-Leukemic Activity of Smac-Mimetics.

    Science.gov (United States)

    Lalaoui, Najoua; Hänggi, Kay; Brumatti, Gabriela; Chau, Diep; Nguyen, Nhu-Y N; Vasilikos, Lazaros; Spilgies, Lisanne M; Heckmann, Denise A; Ma, Chunyan; Ghisi, Margherita; Salmon, Jessica M; Matthews, Geoffrey M; de Valle, Elisha; Moujalled, Donia M; Menon, Manoj B; Spall, Sukhdeep Kaur; Glaser, Stefan P; Richmond, Jennifer; Lock, Richard B; Condon, Stephen M; Gugasyan, Raffi; Gaestel, Matthias; Guthridge, Mark; Johnstone, Ricky W; Munoz, Lenka; Wei, Andrew; Ekert, Paul G; Vaux, David L; Wong, W Wei-Lynn; Silke, John

    2016-02-01

    Birinapant is a smac-mimetic (SM) in clinical trials for treating cancer. SM antagonize inhibitor of apoptosis (IAP) proteins and simultaneously induce tumor necrosis factor (TNF) secretion to render cancers sensitive to TNF-induced killing. To enhance SM efficacy, we screened kinase inhibitors for their ability to increase TNF production of SM-treated cells. We showed that p38 inhibitors increased TNF induced by SM. Unexpectedly, even though p38 is required for Toll-like receptors to induce TNF, loss of p38 or its downstream kinase MK2 increased induction of TNF by SM. Hence, we show that the p38/MK2 axis can inhibit or promote TNF production, depending on the stimulus. Importantly, clinical p38 inhibitors overcame resistance of primary acute myeloid leukemia to birinapant.

  13. Contribution of BDNF/TrkB pathway to development of neuropathic pain by activation of astrocytes in rats%BDNF/TrkB通路活化星形胶质细胞对大鼠神经病理性痛的影响

    Institute of Scientific and Technical Information of China (English)

    汪静; 张昕; 江伟; 杜冬萍

    2012-01-01

    detected by Western blotting. Results Compared with blank control group, 50% PWT of hind limbs in BDNF group was significantly lower (P 0. 05). There was no significant difference in the expression of phosphorylated TrkB protein between BDNF + K252a group and blank control group ( P > 0. 05). Conclusion BDNF may activate astrocytes via phosphorylated TrkB receptor, which in turn produce neuropathic pain.

  14. Prenatal Cocaine Exposure Upregulates BDNF-TrkB Signaling

    Science.gov (United States)

    Stucky, Andres; Bakshi, Kalindi P.; Friedman, Eitan; Wang, Hoau-Yan

    2016-01-01

    Prenatal cocaine exposure causes profound changes in neurobehavior as well as synaptic function and structure with compromised glutamatergic transmission. Since synaptic health and glutamatergic activity are tightly regulated by brain-derived neurotrophic factor (BDNF) signaling through its cognate tyrosine receptor kinase B (TrkB), we hypothesized that prenatal cocaine exposure alters BDNF-TrkB signaling during brain development. Here we show prenatal cocaine exposure enhances BDNF-TrkB signaling in hippocampus and prefrontal cortex (PFCX) of 21-day-old rats without affecting the expression levels of TrkB, P75NTR, signaling molecules, NMDA receptor—NR1 subunit as well as proBDNF and BDNF. Prenatal cocaine exposure reduces activity-dependent proBDNF and BDNF release and elevates BDNF affinity for TrkB leading to increased tyrosine-phosphorylated TrkB, heightened Phospholipase C-γ1 and N-Shc/Shc recruitment and higher downstream PI3K and ERK activation in response to ex vivo BDNF. The augmented BDNF-TrkB signaling is accompanied by increases in association between activated TrkB and NMDARs. These data suggest that cocaine exposure during gestation upregulates BDNF-TrkB signaling and its interaction with NMDARs by increasing BDNF affinity, perhaps in an attempt to restore the diminished excitatory neurotransmission. PMID:27494324

  15. Prenatal Cocaine Exposure Upregulates BDNF-TrkB Signaling.

    Science.gov (United States)

    Stucky, Andres; Bakshi, Kalindi P; Friedman, Eitan; Wang, Hoau-Yan

    2016-01-01

    Prenatal cocaine exposure causes profound changes in neurobehavior as well as synaptic function and structure with compromised glutamatergic transmission. Since synaptic health and glutamatergic activity are tightly regulated by brain-derived neurotrophic factor (BDNF) signaling through its cognate tyrosine receptor kinase B (TrkB), we hypothesized that prenatal cocaine exposure alters BDNF-TrkB signaling during brain development. Here we show prenatal cocaine exposure enhances BDNF-TrkB signaling in hippocampus and prefrontal cortex (PFCX) of 21-day-old rats without affecting the expression levels of TrkB, P75NTR, signaling molecules, NMDA receptor-NR1 subunit as well as proBDNF and BDNF. Prenatal cocaine exposure reduces activity-dependent proBDNF and BDNF release and elevates BDNF affinity for TrkB leading to increased tyrosine-phosphorylated TrkB, heightened Phospholipase C-γ1 and N-Shc/Shc recruitment and higher downstream PI3K and ERK activation in response to ex vivo BDNF. The augmented BDNF-TrkB signaling is accompanied by increases in association between activated TrkB and NMDARs. These data suggest that cocaine exposure during gestation upregulates BDNF-TrkB signaling and its interaction with NMDARs by increasing BDNF affinity, perhaps in an attempt to restore the diminished excitatory neurotransmission. PMID:27494324

  16. Structural basis of activation-dependent binding of ligand-mimetic antibody AL-57 to integrin LFA-1

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongmin; Liu, Jin-huan; Yang, Wei; Springer, Timothy; Shimaoka, Motomu; Wang, Jia-huai; (CH-Boston); (DFCI)

    2010-09-21

    The activity of integrin LFA-1 ({alpha}{sub L}{beta}{sub 2}) to its ligand ICAM-1 is regulated through the conformational changes of its ligand-binding domain, the I domain of {alpha}{sub L} chain, from an inactive, low-affinity closed form (LA), to an intermediate-affinity form (IA), and then finally, to a high-affinity open form (HA). A ligand-mimetic human monoclonal antibody AL-57 (activated LFA-1 clone 57) was identified by phage display to specifically recognize the affinity-upregulated I domain. Here, we describe the crystal structures of the Fab fragment of AL-57 in complex with IA, as well as in its unligated form. We discuss the structural features conferring AL-57's strong selectivity for the high affinity, open conformation of the I domain. The AL-57-binding site overlaps the ICAM-1 binding site on the I domain. Furthermore, an antibody Asp mimics an ICAM Glu by forming a coordination to the metal-ion dependent adhesion site (MIDAS). The structure also reveals better shape complementarity and a more hydrophobic interacting interface in AL-57 binding than in ICAM-1 binding. The results explain AL-57's antagonistic mimicry of LFA-1's natural ligands, the ICAM molecules.

  17. Mimetic discretization methods

    CERN Document Server

    Castillo, Jose E

    2013-01-01

    To help solve physical and engineering problems, mimetic or compatible algebraic discretization methods employ discrete constructs to mimic the continuous identities and theorems found in vector calculus. Mimetic Discretization Methods focuses on the recent mimetic discretization method co-developed by the first author. Based on the Castillo-Grone operators, this simple mimetic discretization method is invariably valid for spatial dimensions no greater than three. The book also presents a numerical method for obtaining corresponding discrete operators that mimic the continuum differential and

  18. Iron oxide superparamagnetic nanoparticles conjugated with a conformationally blocked α-Tn antigen mimetic for macrophage activation

    Science.gov (United States)

    Manuelli, Massimo; Fallarini, Silvia; Lombardi, Grazia; Sangregorio, Claudio; Nativi, Cristina; Richichi, Barbara

    2014-06-01

    Among new therapies to fight tumors, immunotherapy is still one of the most promising and intriguing. Thanks to the ongoing structural elucidation of several tumor antigens and the development of innovative antigen carriers, immunotherapy is in constant evolution and it is largely used either alone or in synergy with chemotherapy/radiotherapy. With the aim to develop fully synthetic immunostimulants we have recently developed a mimetic of the α-Tn mucin antigen, a relevant tumor antigen. The 4C1 blocked mimetic 1, unique example of an α-Tn mimetic antigen, was functionalized with an ω-phosphonate linker and used to decorate iron oxide superparamagnetic nanoparticles (MNPs), employed as multivalent carriers. MNPs, largely exploited for supporting and carrying biomolecules, like antibodies, drugs or antigens, consent to combine in the same nanometric system the main features of an inorganic magnetic core with a bioactive organic coating. The superparamagnetic glyconanoparticles obtained, named GMNPs, are indeed biocompatible and immunoactive, and they preserve suitable characteristics for use as heat mediators in the magnetic fluid hyperthermia (MFH) treatment of tumors. All together these properties make GMNPs attracting devices for innovative tumor treatment.Among new therapies to fight tumors, immunotherapy is still one of the most promising and intriguing. Thanks to the ongoing structural elucidation of several tumor antigens and the development of innovative antigen carriers, immunotherapy is in constant evolution and it is largely used either alone or in synergy with chemotherapy/radiotherapy. With the aim to develop fully synthetic immunostimulants we have recently developed a mimetic of the α-Tn mucin antigen, a relevant tumor antigen. The 4C1 blocked mimetic 1, unique example of an α-Tn mimetic antigen, was functionalized with an ω-phosphonate linker and used to decorate iron oxide superparamagnetic nanoparticles (MNPs), employed as multivalent

  19. BDNF, produced by a TPO-stimulated megakaryocytic cell line, regulates autocrine proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, Shogo [Graduate School of Health Sciences, Hokkaido University, Sapporo (Japan); Research Fellow of the Japan Society for the Promotion of Science, Tokyo (Japan); Nagasawa, Ayumi; Masuda, Yuya; Tsunematsu, Tetsuya [Graduate School of Health Sciences, Hokkaido University, Sapporo (Japan); Hayasaka, Koji; Matsuno, Kazuhiko; Shimizu, Chikara [Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Sapporo (Japan); Ozaki, Yukio [Department of Clinical and Laboratory Medicine, Faculty of Medicine, University of Yamanashi (Japan); Moriyama, Takanori, E-mail: moriyama@hs.hokuda.ac.jp [Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Sapporo (Japan)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer It has been thought that BDNF is not produced in the megakaryocytic lineage. Black-Right-Pointing-Pointer MEG-01 produces BDNF upon TPO stimulation and regulates its proliferation. Black-Right-Pointing-Pointer BDNF accelerates proliferation of MEG-01 in an autocrine manner. Black-Right-Pointing-Pointer BDNF may be an autocrine MEG-CSF, which regulates megakaryopoiesis. -- Abstract: While human platelets release endogenous brain-derived neurotrophic factor (BDNF) upon activation, a previous report on MEG-01, a megakaryocytic cell line, found no trace of BDNF production, and the pathophysiological function of platelet BDNF has remained elusive. In the present study, we demonstrate that MEG-01 produces BDNF in the presence of TPO and that this serves to potentiate cell proliferation. Our in vitro findings suggest that BDNF regulates MEG-01 proliferation in an autocrine manner, and we suggest that BDNF may be a physiological autocrine regulator of megakaryocyte progenitors.

  20. Unimodular-Mimetic Cosmology

    CERN Document Server

    Nojiri, S; Oikonomou, V K

    2016-01-01

    We combine the unimodular gravity and mimetic gravity theories into a unified theoretical framework, which is proposed to solve the cosmological constant problem and the dark matter issue. After providing the formulation of the unimodular mimetic gravity and investigating all the new features that the vacuum unimodular gravity implies, by using the underlying reconstruction method, we realize some well known cosmological evolutions, with some of these being exotic for the ordinary Einstein-Hilbert gravity. Specifically we provide the vacuum unimodular mimetic gravity description of the de Sitter cosmology, of the perfect fluid with constant equation of state cosmology, of the Type IV singular cosmology and of the $R^2$ inflation cosmology. Moreover, we investigate how cosmologically viable cosmologies, which are compatible with the recent observational data, can be realized by the vacuum unimodular mimetic gravity. Since in some cases, the graceful exit from inflation problem might exist, we provide a qualita...

  1. Unimodular-mimetic cosmology

    Science.gov (United States)

    Nojiri, S.; Odintsov, S. D.; Oikonomou, V. K.

    2016-06-01

    We combine the unimodular gravity and mimetic gravity theories into a unified theoretical framework, which is proposed to provide a suggestive proposal for a framework that may assist in the discussion and search for a solution to the cosmological constant problem and the dark matter issue. After providing the formulation of the unimodular mimetic gravity and investigating all the new features that the vacuum unimodular gravity implies, by using the underlying reconstruction method, we realize some well known cosmological evolutions, with some of these being exotic for the ordinary Einstein-Hilbert gravity. Specifically we provide the vacuum unimodular mimetic gravity description of the de Sitter cosmology and of the perfect fluid with constant equation of state cosmology. As we demonstrate, these cosmologies can be realized by vacuum mimetic unimodular gravity, without the existence of any matter fluid source. Moreover, we investigate how cosmologically viable cosmologies, which are compatible with the recent observational data, can be realized by the vacuum unimodular mimetic gravity. Since in some cases, a graceful exit from inflation problem might exist, we provide a qualitative description of the mechanism that can potentially generate the graceful exit from inflation in these theories, by searching for the unstable de Sitter solutions in the context of unimodular mimetic theories of gravity.

  2. Identification of antiviral mimetic peptides with interferon α-2b-like activity from a random peptide library using a novel functional biopanning method

    Institute of Scientific and Technical Information of China (English)

    Qi ZHANG; Gang BAI; Jia-qi CHEN; Wang TIAN; Yu CAO; Peng-wei PAN; Chao WANG

    2008-01-01

    Aim: To screen for interferon (IFN) α-2b mimetic peptides with antiviral activity. Methods: Selecting IFN receptor-binding peptides from a phage-display heptapeptide library using a novel functional biopanning method. This method was developed to identify peptides with activity against vesicular stomatitis virus (VSV) inducing cytopathic effects on WISH cells. Results: Sixteen positive clones were obtained after 3 rounds of functional selection. Ten clones were picked from these positive clones according to the results of phage ELISA and were sequenced. The amino acid sequences homologous to IFNα-2b were defined by residues AB loop 31-37, BC loop 68-74, C helix 93-99, CD loop 106-112, D helix 115-121, DE loop 132-138, and E helix 143-161. Two of the peptides, designated clones T3 and T9, aligned with the IFNAR2-binding domains (AB loop and E helix), were synthe-sized and designated as IR-7 and KP-7, respectively. Both KP-7 and IR-7 were found to compete with GFP/IFNtα-2b for receptor binding and mimicked the antivi-ral activity of IFNα-2b cooperatively. Conclusion: Two IFNα-2b mimetic peptides with antiviral activity were derived from a phage-display heptapeptide library using a novel functional selection method.

  3. Highly stable hexacoordinated nonoxidovanadium(IV) complexes of sterically constrained ligands: syntheses, structure, and study of antiproliferative and insulin mimetic activity.

    Science.gov (United States)

    Dash, Subhashree P; Pasayat, Sagarika; Bhakat, Saswati; Roy, Satabdi; Dinda, Rupam; Tiekink, Edward R T; Mukhopadhyay, Subhadip; Bhutia, Sujit K; Hardikar, Manasi R; Joshi, Bimba N; Patil, Yogesh P; Nethaji, M

    2013-12-16

    Three highly stable, hexacoordinated nonoxidovanadium(IV), V(IV)(L)2, complexes (1-3) have been isolated and structurally characterized with tridentate aroylhydrazonates containing ONO donor atoms. All the complexes are stable in the open air in the solid state as well as in solution, a phenomenon rarely observed in nonoxidovanadium(IV) complexes. The complexes have good solubility in organic solvents, permitting electrochemical and various spectroscopic investigations. The existence of nonoxidovanadium(IV) complexes was confirmed by elemental analysis, ESI mass spectroscopy, cyclic voltammetry, EPR, and magnetic susceptibility measurements. X-ray crystallography showed the N3O3 donor set to define a trigonal prismatic geometry in each case. All the complexes show in vitro insulin mimetic activity against insulin responsive L6 myoblast cells, with complex 3 being the most potent, which is comparable to insulin at the complex concentration of 4 μM, while the others have moderate insulin mimetic activity. In addition, the in vitro antiproliferative activity of complexes 1-3 against the HeLa cell line was assayed. The cytotoxicity of the complexes is affected by the various functional groups attached to the bezoylhydrazone derivative and 2 showed considerable antiproliferative activity compared to the most commonly used chemotherapeutic drugs.

  4. Synthesis, characterization and phosphotriesterase mimetic activity of some Zn(II) and Cu(II) complexes

    Indian Academy of Sciences (India)

    Mamata Singh; Ray J Butcher; Jerry P Jasinski; James A Golen; Govindasamy Mugesh

    2012-11-01

    We report here the synthesis and characterization of a few phenolate-based ligands bearing tertamino substituent and their Zn(II) and Cu(II) metal complexes. Three mono/binuclear Zn(II) and Cu(II) complexes [Zn(L1)(H2O)].CH3OH.H2O (1) (H2 L1 = 6,6′-(((2-dimethylamino)ethylazanediyl)bis(methylene))bis(2, 4-dimethylphenol), [Zn2(L2)2] (2) (H2L2 = 2,2′-(((2-dimethylamino)ethyl)azanediyl)bis(methylene)bis(4-methylphenol) and [Cu2(L3)2.CH2 Cl2] (3) (H2L3 = (6,6′-(((2-(diethylamino)ethyl)azanediyl)bis(methylene)) bis(methylene))bis(2,4-dimethylphenol) were synthesized by using three symmetrical tetradendate ligands containing N2O2 donor sites. These complexes are characterized by a variety of techniques including; elemental analysis, mass spectrometry, 1H, 13C NMR spectroscopic and single crystal X-ray analysis. The new complexes have been tested for the phosphotriesterase (PTE) activity with the help of 31P NMR spectroscopy. The 31P NMR studies show that mononuclear complex [Zn(L1)(H2O)].CH3OH.H2O (1) can hydrolyse the phosphotriester i.e., p-nitrophenyl diphenylphosphate (PNPDPP), more efficiently than the binuclear complexes [Zn2(L2)2] (2) and [Cu2(L3)2.CH2Cl2] (3). The mononuclear Zn(II) complex (1) having one coordinated water molecule exhibits significant PTE activity which may be due to the generation of a Zn(II)-bound hydroxide ion during the hydrolysis reactions in CHES buffer at pH 9.0.

  5. Effects of BDNF Polymorphisms on Antidepressant Action

    OpenAIRE

    Tsai, Shih-Jen; Hong, Chen-Jee; Liou, Ying-Jay

    2010-01-01

    Evidence suggests that the down-regulation of the signaling pathway involving brain-derived neurotrophic factor (BDNF), a molecular element known to regulate neuronal plasticity and survival, plays an important role in the pathogenesis of major depression. The restoration of BDNF activity induced by antidepressant treatment has been implicated in the antidepressant therapeutic mechanism. Because there is variability among patients with major depressive disorder in terms of response to antidep...

  6. Peptides derived from the solvent-exposed loops 3 and 4 of BDNF bind TrkB and p75(NTR) receptors and stimulate neurite outgrowth and survival

    DEFF Research Database (Denmark)

    Fobian, Kristina; Owczarek, Sylwia; Budtz, Christian;

    2010-01-01

    Brain-derived neurotrophic factor (BDNF) is critically involved in modeling the developing nervous system and is an important regulator of a variety of crucial functions in the mature CNS. BDNF exerts its action through interactions with two transmembrane receptors, either separately or in concert....... BDNF has been implicated in several neurological disorders, and irregularities in BDNF function may have severe consequences. Administration of BDNF as a drug has thus far yielded few practicable results, and the potential side effects when using a multifunctional protein are substantial. In an effort...... to produce more specific compounds without side effects, small peptides mimicking protein function have been developed. The present study characterized two mimetic peptides, Betrofin 3 and Betrofin 4, derived from the BDNF sequence. Both Betrofins bound the cognate BDNF receptors, TrkB and p75(NTR...

  7. Significant in vivo anti-inflammatory activity of Pytren4Q-Mn a superoxide dismutase 2 (SOD2 mimetic scorpiand-like Mn (II complex.

    Directory of Open Access Journals (Sweden)

    Carolina Serena

    Full Text Available The clinical use of purified SOD enzymes has strong limitations due to their large molecular size, high production cost and immunogenicity. These limitations could be compensated by using instead synthetic SOD mimetic compounds of low molecular weight.We have recently reported that two SOD mimetic compounds, the Mn(II complexes of the polyamines Pytren2Q and Pytren4Q, displayed high antioxidant activity in bacteria and yeast. Since frequently molecules with antioxidant properties or free-radical scavengers also have anti-inflammatory properties we have assessed the anti-inflammatory potential of Pytren2Q and Pytren4Q Mn(II complexes, in cultured macrophages and in a murine model of inflammation, by measuring the degree of protection they could provide against the cellular injury produced by lipopolisacharide, a bacterial endotoxin.In this report we show that the Mn(II complex of Pytren4Q but not that of Pytren2Q effectively protected human cultured THP-1 macrophages and whole mice from the inflammatory effects produced by LPS. These results obtained with two molecules that are isomers highlight the importance of gathering experimental data from animal models of disease in assessing the potential of candidate molecules.The effective anti-inflammatory activity of the Mn(II complex of Pytren4Q in addition to its low toxicity, water solubility and ease of production would suggest it is worth taking into consideration for future pharmacological studies.

  8. Mimetic finite difference method

    Science.gov (United States)

    Lipnikov, Konstantin; Manzini, Gianmarco; Shashkov, Mikhail

    2014-01-01

    The mimetic finite difference (MFD) method mimics fundamental properties of mathematical and physical systems including conservation laws, symmetry and positivity of solutions, duality and self-adjointness of differential operators, and exact mathematical identities of the vector and tensor calculus. This article is the first comprehensive review of the 50-year long history of the mimetic methodology and describes in a systematic way the major mimetic ideas and their relevance to academic and real-life problems. The supporting applications include diffusion, electromagnetics, fluid flow, and Lagrangian hydrodynamics problems. The article provides enough details to build various discrete operators on unstructured polygonal and polyhedral meshes and summarizes the major convergence results for the mimetic approximations. Most of these theoretical results, which are presented here as lemmas, propositions and theorems, are either original or an extension of existing results to a more general formulation using polyhedral meshes. Finally, flexibility and extensibility of the mimetic methodology are shown by deriving higher-order approximations, enforcing discrete maximum principles for diffusion problems, and ensuring the numerical stability for saddle-point systems.

  9. BDNF Selectively Regulates GABAA Receptor Transcription by Activation of the JAK/STAT Pathway

    OpenAIRE

    Lund, Ingrid V.; Hu, Yinghui; Raol, YogendraSinh H.; Benham, Rebecca S.; Faris, Ramona; Russek, Shelley J.; Brooks-Kayal, Amy R.

    2008-01-01

    The γ-aminobutyric acid (GABA) type A receptor (GABAAR) is the major inhibitory neurotransmitter receptor in the brain. Its multiple subunits show regional, developmental, and disease-related plasticity of expression; however, the regulatory networks controlling GABAAR subunit expression remain poorly understood. We report that the seizure-induced decrease in GABAAR α1 subunit expression associated with epilepsy is mediated by the Janus kinase (JAK)/signal transducer and activator of transcri...

  10. SuperMimic – Fitting peptide mimetics into protein structures

    Directory of Open Access Journals (Sweden)

    Schmidt Ulrike

    2006-01-01

    Full Text Available Abstract Background Various experimental techniques yield peptides that are biologically active but have unfavourable pharmacological properties. The design of structurally similar organic compounds, i.e. peptide mimetics, is a challenging field in medicinal chemistry. Results SuperMimic identifies compounds that mimic parts of a protein, or positions in proteins that are suitable for inserting mimetics. The application provides libraries that contain peptidomimetic building blocks on the one hand and protein structures on the other. The search for promising peptidomimetic linkers for a given peptide is based on the superposition of the peptide with several conformers of the mimetic. New synthetic elements or proteins can be imported and used for searching. Conclusion We present a graphical user interface for finding peptide mimetics that can be inserted into a protein or for fitting small molecules into a protein. Using SuperMimic, promising locations in proteins for the insertion of mimetics can be found quickly and conveniently.

  11. SuperMimic – Fitting peptide mimetics into protein structures

    Science.gov (United States)

    Goede, Andrean; Michalsky, Elke; Schmidt, Ulrike; Preissner, Robert

    2006-01-01

    Background Various experimental techniques yield peptides that are biologically active but have unfavourable pharmacological properties. The design of structurally similar organic compounds, i.e. peptide mimetics, is a challenging field in medicinal chemistry. Results SuperMimic identifies compounds that mimic parts of a protein, or positions in proteins that are suitable for inserting mimetics. The application provides libraries that contain peptidomimetic building blocks on the one hand and protein structures on the other. The search for promising peptidomimetic linkers for a given peptide is based on the superposition of the peptide with several conformers of the mimetic. New synthetic elements or proteins can be imported and used for searching. Conclusion We present a graphical user interface for finding peptide mimetics that can be inserted into a protein or for fitting small molecules into a protein. Using SuperMimic, promising locations in proteins for the insertion of mimetics can be found quickly and conveniently. PMID:16403211

  12. Antidepressant-like activity of resveratrol treatment in the forced swim test and tail suspension test in mice: the HPA axis, BDNF expression and phosphorylation of ERK.

    Science.gov (United States)

    Wang, Zhen; Gu, Jianhua; Wang, Xueer; Xie, Kai; Luan, Qinsong; Wan, Nianqing; Zhang, Qun; Jiang, Hong; Liu, Dexiang

    2013-11-01

    Resveratrol is a natural polyphenol enriched in Polygonum cuspidatum and has diverse biological activities. There is only limited information about the antidepressant-like effect of resveratrol. The present study assessed whether resveratrol treatment (20, 40 and 80mg/kg, i.p., 21days) has an antidepressant-like effect on the forced swim test (FST) and tail suspension test (TST) in mice and examined what its molecular targets might be. The results showed that resveratrol administration produced antidepressant-like effects in mice, evidenced by the reduced immobility time in the FST and TST, while it had no effect on the locomotor activity in the open field test. Resveratrol treatment significantly reduced serum corticosterone levels, which had been elevated by the FST and TST. Moreover, resveratrol increased brain-derived neurotrophic factor (BDNF) protein and extracellular signal-regulated kinase (ERK) phosphorylation levels in the prefrontal cortex and hippocampus. All of these antidepressant-like effects of resveratrol were essentially similar to those observed with the clinical antidepressant, fluoxetine. These results suggest that the antidepressant-like effects of resveratrol in the FST and TST are mediated, at least in part, by modulating hypothalamic-pituitary-adrenal axis, BDNF and ERK phosphorylation expression in the brain region of mice.

  13. Synthetic oligosaccharides as heparin-mimetics displaying anticoagulant properties.

    Science.gov (United States)

    Avci, Fikri Y; Karst, Nathalie A; Linhardt, Robert J

    2003-01-01

    Heparin and low molecular weight heparins are major clinical anticoagulants and the drugs of choice for the treatment of deep venous thrombosis. The discovery of an antithrombin binding domain in heparin focused interest on understanding the mechanism of heparin's antithrombotic/ anticoagulant activity. Various heparin-mimetic oligosaccharides have been prepared in an effort to replace polydisperse heparin and low molecular weight heparins with a structurally-defined anticoagulant. The goal of attaining a heparin-mimetic with no unwanted side-effects has also provided motivation for these efforts. This article reviews structure-activity relationship (SAR) of structurally-defined heparin-mimetic oligosaccharides. PMID:14529394

  14. Mimetic Compact Stars

    CERN Document Server

    Momeni, D; Gholizade, H; Myrzakulov, R

    2015-01-01

    Modified gravity models have been constantly proposed with the purpose of evading some standard gravity shortcomings. Recently proposed by A.H. Chamseddine and V. Mukhanov, the Mimetic Gravity arises as an optimistic alternative. Our purpose in this work is to derive Tolman-Oppenheimer-Volkoff equations and solutions for such a gravity theory. We solve them numerically for quark star and neutron star cases. The results are carefully discussed.

  15. BDNF pro-peptide actions facilitate hippocampal LTD and are altered by the common BDNF polymorphism Val66Met.

    Science.gov (United States)

    Mizui, Toshiyuki; Ishikawa, Yasuyuki; Kumanogoh, Haruko; Lume, Maria; Matsumoto, Tomoya; Hara, Tomoko; Yamawaki, Shigeto; Takahashi, Masami; Shiosaka, Sadao; Itami, Chiaki; Uegaki, Koichi; Saarma, Mart; Kojima, Masami

    2015-06-01

    Most growth factors are initially synthesized as precursor proteins and subsequently processed into their mature form by proteolytic cleavage, resulting in simultaneous removal of a pro-peptide. However, compared with that of mature form, the biological role of the pro-peptide is poorly understood. Here, we investigated the biological role of the pro-peptide of brain-derived neurotrophic factor (BDNF) and first showed that the pro-peptide is expressed and secreted in hippocampal tissues and cultures, respectively. Interestingly, we found that the BDNF pro-peptide directly facilitates hippocampal long-term depression (LTD), requiring the activation of GluN2B-containing NMDA receptors and the pan-neurotrophin receptor p75(NTR). The BDNF pro-peptide also enhances NMDA-induced α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor endocytosis, a mechanism crucial for LTD expression. Thus, the BDNF pro-peptide is involved in synaptic plasticity that regulates a mechanism responsible for promoting LTD. The well-known BDNF polymorphism valine for methionine at amino acid position 66 (Val66Met) affects human memory function. Here, the BDNF pro-peptide with Met mutation completely inhibits hippocampal LTD. These findings demonstrate functional roles for the BDNF pro-peptide and a naturally occurring human BDNF polymorphism in hippocampal synaptic depression. PMID:26015580

  16. Apolipoprotein E mimetic peptide protects against diffuse brain injur y

    Institute of Scientific and Technical Information of China (English)

    Yaning Zhao; Jianmin Li; Qiqun Tang; Junling Gao; Changxiang Chen; Liwei Jing; Pan Zhang; Shuxing Li

    2014-01-01

    Apolipoprotein E plays a crucial role in inhibiting chronic neurodegenerative processes. Howev-er, its impact on neurological function following diffuse brain injury is still unclear. This study was designed to evaluate the therapeutic effects and mechanisms of action of apolipoprotein E mimetic peptide on diffuse brain injury. Apolipoprotein E mimetic peptide was administered into the caudal vein of rats with diffuse brain injury before and after injury. We found that apo-lipoprotein E mimetic peptide signiifcantly decreased the number of apoptotic neurons, reduced extracellular signal-regulated kinase1/2 phosphorylation, down-regulated Bax and cytochrome c expression, decreased malondialdehyde content, and increased superoxide dismutase activity in a dose-dependent manner. These experimental ifndings demonstrate that apolipoprotein E mimetic peptide improves learning and memory function and protects against diffuse brain injury-induced apoptosis by inhibiting the extracellular signal-regulated kinase1/2-Bax mito-chondrial apoptotic pathway.

  17. Promises and Challenges of Smac Mimetics as Cancer Therapeutics.

    Science.gov (United States)

    Fulda, Simone

    2015-11-15

    Inhibitor of Apoptosis (IAP) proteins block programmed cell death and are expressed at high levels in various human cancers, thus making them attractive targets for cancer drug development. Second mitochondrial activator of caspases (Smac) mimetics are small-molecule inhibitors that mimic Smac, an endogenous antagonist of IAP proteins. Preclinical studies have shown that Smac mimetics can directly trigger cancer cell death or, even more importantly, sensitize tumor cells for various cytotoxic therapies, including conventional chemotherapy, radiotherapy, or novel agents. Currently, several Smac mimetics are under evaluation in early clinical trials as monotherapy or in rational combinations (i.e., GDC-0917/CUDC-427, LCL161, AT-406/Debio1143, HGS1029, and TL32711/birinapant). This review discusses the promise as well as some challenges at the translational interface of exploiting Smac mimetics as cancer therapeutics.

  18. BDNF — EDRN Public Portal

    Science.gov (United States)

    BDNF (brain-derived neurotrophic factor) is a member of the nerve growth factor family. It is induced by cortical neurons, and is necessary for survival of striatal neurons in the brain. During development, BDNF promotes the survival and differentiation of selected neuronal populations of the peripheral and central nervous systems. Decreased expression of the BDNF gene is seen in both Alzheimer's and Huntington disease patients. BDNF may play a role in the regulation of stress response and in the biology of mood disorders. Multiple transcript variants encoding distinct isoforms have been described for this gene.

  19. Mechanisms of BDNF regulation in asthmatic airway smooth muscle.

    Science.gov (United States)

    Aravamudan, Bharathi; Thompson, Michael A; Pabelick, Christina M; Prakash, Y S

    2016-08-01

    Brain-derived neurotrophic factor (BDNF), a neurotrophin produced by airway smooth muscle (ASM), enhances inflammation effects on airway contractility, supporting the idea that locally produced growth factors influence airway diseases such as asthma. We endeavored to dissect intrinsic mechanisms regulating endogenous, as well as inflammation (TNF-α)-induced BDNF secretion in ASM of nonasthmatic vs. asthmatic humans. We focused on specific Ca(2+) regulation- and inflammation-related signaling cascades and quantified BDNF secretion. We find that TNF-α enhances BDNF release by ASM cells, via several mechanisms relevant to asthma, including transient receptor potential channels TRPC3 and TRPC6 (but not TRPC1), ERK 1/2, PI3K, PLC, and PKC cascades, Rho kinase, and transcription factors cAMP response element binding protein and nuclear factor of activated T cells. Basal BDNF expression and secretion are elevated in asthmatic ASM and increase further with TNF-α exposure, involving many of these regulatory mechanisms. We conclude that airway BDNF secretion is regulated at multiple levels, providing a basis for autocrine effects of BDNF under conditions of inflammation and disease, with potential downstream influences on contractility and remodeling. PMID:27317689

  20. Loss of BDNF or Its Receptors in Three Mouse Models Has Unpredictable Consequences for Anxiety and Fear Acquisition

    Science.gov (United States)

    Olsen, Ditte; Kaas, Mathias; Schwartz, Ole; Nykjaer, Anders; Glerup, Simon

    2013-01-01

    BDNF-induced signaling is essential for the development of the central nervous system and critical for plasticity in adults. Mature BDNF signals through TrkB, while its precursor proBDNF employs p75[superscript NTR], resulting in activation of signaling cascades with opposite effects on neuronal survival, growth cone decisions, and synaptic…

  1. Cylindrical solutions in mimetic gravity

    Energy Technology Data Exchange (ETDEWEB)

    Momeni, Davood; Myrzakulov, Kairat; Myrzakulov, Ratbay [Eurasian National University, Eurasian International Center for Theoretical Physics and Department of General and Theoretical Physics, Astana (Kazakhstan); Raza, Muhammad [COMSATS Institute of Information Technology, Department of Mathematics, Sahiwal (Pakistan)

    2016-06-15

    This paper is devoted to investigate cylindrical solutions in mimetic gravity. The explicit forms of the metric of this theory, namely mimetic-Kasner (say) have been obtained. In this study we have noticed that the Kasner's family of exact solutions needs to be reconsidered under this type of modified gravity. A no-go theorem is proposed for the exact solutions in the presence of a cosmological constant. (orig.)

  2. Transcript-specific effects of adrenalectomy on seizure-induced BDNF expression in rat hippocampus

    DEFF Research Database (Denmark)

    Lauterborn, J C; Poulsen, F R; Stinis, C T;

    1998-01-01

    Activity-induced brain-derived neurotrophic factor (BDNF) expression is negatively modulated by circulating adrenal steroids. The rat BDNF gene gives rise to four major transcript forms that each contain a unique 5' exon (I-IV) and a common 3' exon (V) that codes for BDNF protein. Exon......-specific in situ hybridization was used to determine if adrenalectomy has differential effects on basal and activity-induced BDNF transcript expression in hippocampus. Adrenalectomy alone had only modest effects on BDNF mRNA levels with slight increases in exon III-containing mRNA with 7-10-day survival...... no effect on exon IV-containing mRNA content. These results demonstrate that the negative effects of adrenal hormones on activity-induced BDNF expression are by far the greatest for transcripts containing exons I and II. Together with evidence for region-specific transcript expression, these results suggest...

  3. Combined cisplatin and aurora inhibitor treatment increase neuroblastoma cell death but surviving cells overproduce BDNF.

    Science.gov (United States)

    Polacchini, Alessio; Albani, Clara; Baj, Gabriele; Colliva, Andrea; Carpinelli, Patrizia; Tongiorgi, Enrico

    2016-07-15

    Drug-resistance to chemotherapics in aggressive neuroblastoma (NB) is characterized by enhanced cell survival mediated by TrkB and its ligand, brain-derived neurotrophic factor (BDNF); thus reduction in BDNF levels represent a promising strategy to overcome drug-resistance, but how chemotherapics regulate BDNF is unknown. Here, cisplatin treatment in SK-N-BE neuroblastoma upregulated multiple BDNF transcripts, except exons 5 and 8 variants. Cisplatin increased BDNF mRNA and protein, and enhanced translation of a firefly reporter gene flanked by BDNF 5'UTR exons 1, 2c, 4 or 6 and 3'UTR-long. To block BDNF translation we focused on aurora kinases inhibitors which are proposed as new chemotherapeutics. NB cell survival after 24 h treatment was 43% with cisplatin, and 22% by cisplatin+aurora kinase inhibitor PHA-680632, while the aurora kinases inhibitor alone was less effective; however the combined treatment induced a paradoxical increase of BDNF in surviving cells with strong translational activation of exon6-3'UTR-long transcript, while translation of BDNF transcripts 1, 2C and 4 was suppressed. In conclusion, combined cisplatin and aurora kinase inhibitor treatment increases cell death, but induces BDNF overproduction in surviving cells through an aurora kinase-independent mechanism.

  4. Amyloid-Beta Induced Changes in Vesicular Transport of BDNF in Hippocampal Neurons

    Directory of Open Access Journals (Sweden)

    Bianca Seifert

    2016-01-01

    Full Text Available The neurotrophin brain derived neurotrophic factor (BDNF is an important growth factor in the CNS. Deficits in transport of this secretory protein could underlie neurodegenerative diseases. Investigation of disease-related changes in BDNF transport might provide insights into the cellular mechanism underlying, for example, Alzheimer’s disease (AD. To analyze the role of BDNF transport in AD, live cell imaging of fluorescently labeled BDNF was performed in hippocampal neurons of different AD model systems. BDNF and APP colocalized with low incidence in vesicular structures. Anterograde as well as retrograde transport of BDNF vesicles was reduced and these effects were mediated by factors released from hippocampal neurons into the extracellular medium. Transport of BDNF was altered at a very early time point after onset of human APP expression or after acute amyloid-beta(1-42 treatment, while the activity-dependent release of BDNF remained unaffected. Taken together, extracellular cleavage products of APP induced rapid changes in anterograde and retrograde transport of BDNF-containing vesicles while release of BDNF was unaffected by transgenic expression of mutated APP. These early transport deficits might lead to permanently impaired brain functions in the adult brain.

  5. Antifreeze (glyco)protein mimetic behavior of poly(vinyl alcohol): detailed structure ice recrystallization inhibition activity study.

    Science.gov (United States)

    Congdon, Thomas; Notman, Rebecca; Gibson, Matthew I

    2013-05-13

    This manuscript reports a detailed study on the ability of poly(vinyl alcohol) to act as a biomimetic surrogate for antifreeze(glyco)proteins, with a focus on the specific property of ice-recrystallization inhibition (IRI). Despite over 40 years of study, the underlying mechanisms that govern the action of biological antifreezes are still poorly understood, which is in part due to their limited availability and challenging synthesis. Poly(vinyl alcohol) (PVA) has been shown to display remarkable ice recrystallization inhibition activity despite its major structural differences to native antifreeze proteins. Here, controlled radical polymerization is used to synthesize well-defined PVA, which has enabled us to obtain the first quantitative structure-activity relationships, to probe the role of molecular weight and comonomers on IRI activity. Crucially, it was found that IRI activity is "switched on" when the polymer chain length increases from 10 and 20 repeat units. Substitution of the polymer side chains with hydrophilic or hydrophobic units was found to diminish activity. Hydrophobic modifications to the backbone were slightly more tolerated than side chain modifications, which implies an unbroken sequence of hydroxyl units is necessary for activity. These results highlight that, although hydrophobic domains are key components of IRI activity, the random inclusion of addition hydrophobic units does not guarantee an increase in activity and that the actual polymer conformation is important.

  6. BDNF val66met Polymorphism Affects Aging of Multiple Types of Memory

    OpenAIRE

    Kennedy, Kristen M.; Reese, Elizabeth D.; Horn, Marci M.; Sizemore, April N.; Unni, Asha K.; Meerbrey, Michael E.; Kalich, Allan G.; Rodrigue, Karen M.

    2014-01-01

    The BDNF val66met polymorphism (rs6265) influences activity-dependent secretion of brain-derived neurotrophic factor in the synapse, which is crucial for learning and memory. Individuals homozygous or heterozygous for the met allele have lower BDNF secretion than val homozygotes and may be at risk for reduced declarative memory performance, but it remains unclear which types of declarative memory may be affected and how aging of memory across the lifespan is impacted by the BDNF val66met poly...

  7. Functional interactions between steroid hormones and neurotrophin BDNF

    Institute of Scientific and Technical Information of China (English)

    Tadahiro; Numakawa; Daisaku; Yokomaku; Misty; Richards; Hiroaki; Hori; Naoki; Adachi; Hiroshi; Kunugi

    2010-01-01

    Brain-derived neurotrophic factor(BDNF),a critical neurotrophin,regulates many neuronal aspects including cell differentiation,cell survival,neurotransmission,and synaptic plasticity in the central nervous system(CNS) .Though BDNF has two types of receptors,high affinity tropomyosin-related kinase(Trk) B and low affinity p75 receptors,BDNF positively exerts its biological effects on neurons via activation of TrkB and of resultant intracellular signaling cascades including mitogenactivated protein kinase/extracellular signal-regulated protein kinase,phospholipase Cγ,and phosphoinositide 3-kinase pathways.Notably,it is possible that alteration in the expression and/or function of BDNF in the CNS is involved in the pathophysiology of various brain diseases such as stroke,Parkinson’s disease,Alzheimer’s disease,and mental disorders.On the other hand,glucocorticoids,stress-induced steroid hormones,also putatively contribute to the pathophysiology of depression.Interestingly,in addition to the reduction in BDNF levels due to increased glucocorticoid exposure,current reports demonstrate possible interactions between glucocorticoids and BDNF-mediated neuronal functions. Other steroid hormones,such as estrogen,are involved in not only sexual differentiation in the brain,but also numerous neuronal events including cell survival and synaptic plasticity.Furthermore,it is well known that estrogen plays a role in the pathophysiology of Parkinson’s disease,Alzheimer’s disease,and mental illness,while serving to regulate BDNF expression and/or function.Here,we present a broad overview of the current knowledge concerning the association between BDNF expression/function and steroid hormones(glucocorticoids and estrogen).

  8. A simple role for BDNF in learning and memory?

    Directory of Open Access Journals (Sweden)

    Carla Cunha

    2010-02-01

    Full Text Available Since its discovery almost three decades ago, the secreted neurotrophin brain-derived neurotrophic factor (BDNF has been firmly implicated in the differentiation and survival of neurons of the CNS. More recently, BDNF has also emerged as an important regulator of synaptogenesis and synaptic plasticity mechanisms underlying learning and memory in the adult CNS. In this review we will discuss our knowledge about the multiple intracellular signalling pathways activated by BDNF, and the role of this neurotrophin in long-term synaptic plasticity and memory formation as well as in synaptogenesis. We will show that maturation of BDNF, its cellular localisation and its ability to regulate both excitatory and inhibitory synapses in the CNS may result in conflicting alterations in synaptic plasticity and memory formation. Lack of a precise knowledge about the mechanisms by which BDNF influences higher cognitive functions and complex behaviours may constitute a severe limitation in the possibility to devise BDNF-based therapeutics for human disorders of the CNS.

  9. RGTA OTR4120, a heparan sulfate mimetic, is a possible long-term active agent to heal burned skin.

    Science.gov (United States)

    Garcia-Filipe, S; Barbier-Chassefiere, V; Alexakis, C; Huet, E; Ledoux, D; Kerros, M E; Petit, E; Barritault, D; Caruelle, J P; Kern, P

    2007-01-01

    Burn-related skin fibrosis leads to loss of tissue function and hypertrophic scar formation with damaging consequences for the patient. There is therefore a great need for an efficient agent to treat burned skin. We report that ReGeneraTing Agent (RGTA) reduces burn-induced skin alteration. The tissue-regenerating effect of RGTA OTR4120 was evaluated after 1-6 days and after 10 months in a rat skin burn model. This effect was also examined in vitro using fibroblasts isolated from control and 6-day-old burned skins. We measured production of dermal collagen I, III, and V and activities of metalloproteinases 2 and 9 (MMP-2 and MMP-9). Ratio of collagen III over collagen I production increased 6 days after the burn, because of a decrease in collagen I production. After 10 months, ratio of collagen III over collagen I in burn sites was still increased compared with control skin, because of an increase in collagen III production. Both abnormalities were corrected by OTR4120. OTR4120 increased pro- and active MMP-2 and MMP-9, compared with healthy and burned controls and therefore accelerated remodeling. Similar data were obtained with cultured fibroblasts from healthy and burned skins. OTR4120 enhanced healing in short- and long-term after burns, reducing the formation of fibrotic tissue, and then represents a potential agent to improve burned skin healing.

  10. NMDA-Dependent Switch of proBDNF Actions on Developing GABAergic Synapses

    Science.gov (United States)

    Langlois, Anais; Diabira, Diabe; Ferrand, Nadine; Porcher, Christophe

    2013-01-01

    The brain-derived neurotrophic factor (BDNF) has emerged as an important messenger for activity-dependent development of neuronal network. Recent findings have suggested that a significant proportion of BDNF can be secreted as a precursor (proBDNF) and cleaved by extracellular proteases to yield the mature form. While the actions of proBDNF on maturation and plasticity of excitatory synapses have been studied, the effect of the precursor on developing GABAergic synapses remains largely unknown. Here, we show that regulated secretion of proBDNF exerts a bidirectional control of GABAergic synaptic activity with NMDA receptors driving the polarity of the plasticity. When NMDA receptors are activated during ongoing synaptic activity, regulated Ca2+-dependent secretion of proBDNF signals via p75NTR to depress GABAergic synaptic activity, while in the absence of NMDA receptors activation, secreted proBDNF induces a p75NTR-dependent potentiation of GABAergic synaptic activity. These results revealed a new function for proBDNF-p75NTR signaling in synaptic plasticity and a novel mechanism by which synaptic activity can modulate the development of GABAergic synaptic connections. PMID:22510533

  11. Protein tyrosine phosphatase 1B (PTP1B) inhibitors from Morinda citrifolia (Noni) and their insulin mimetic activity.

    Science.gov (United States)

    Nguyen, Phi-Hung; Yang, Jun-Li; Uddin, Mohammad N; Park, So-Lim; Lim, Seong-Il; Jung, Da-Woon; Williams, Darren R; Oh, Won-Keun

    2013-11-22

    As part of our ongoing search for new antidiabetic agents from medicinal plants, we found that a methanol extract of Morinda citrifolia showed potential stimulatory effects on glucose uptake in 3T3-L1 adipocyte cells. Bioassay-guided fractionation of this active extract yielded two new lignans (1 and 2) and three new neolignans (9, 10, and 14), as well as 10 known compounds (3-8, 11-13, and 15). The absolute configurations of compounds 9, 10, and 14 were determined by ECD spectra analysis. Compounds 3, 6, 7, and 15 showed inhibitory effects on PTP1B enzyme with IC50 values of 21.86 ± 0.48, 15.01 ± 0.20, 16.82 ± 0.42, and 4.12 ± 0.09 μM, respectively. Furthermore, compounds 3, 6, 7, and 15 showed strong stimulatory effects on 2-NBDG uptake in 3T3-L1 adipocyte cells. This study indicated the potential of compounds 3, 6, 7, and 15 as lead molecules for antidiabetic agents.

  12. Brain-derived neurotrophic factor (BDNF)-induced mitochondrial motility arrest and presynaptic docking contribute to BDNF-enhanced synaptic transmission.

    Science.gov (United States)

    Su, Bo; Ji, Yun-Song; Sun, Xu-lu; Liu, Xiang-Hua; Chen, Zhe-Yu

    2014-01-17

    Appropriate mitochondrial transport and distribution are essential for neurons because of the high energy and Ca(2+) buffering requirements at synapses. Brain-derived neurotrophic factor (BDNF) plays an essential role in regulating synaptic transmission and plasticity. However, whether and how BDNF can regulate mitochondrial transport and distribution are still unclear. Here, we find that in cultured hippocampal neurons, application of BDNF for 15 min decreased the percentage of moving mitochondria in axons, a process dependent on the activation of the TrkB receptor and its downstream PI3K and phospholipase-Cγ signaling pathways. Moreover, the BDNF-induced mitochondrial stopping requires the activation of transient receptor potential canonical 3 and 6 (TRPC3 and TRPC6) channels and elevated intracellular Ca(2+) levels. The Ca(2+) sensor Miro1 plays an important role in this process. Finally, the BDNF-induced mitochondrial stopping leads to the accumulation of more mitochondria at presynaptic sites. Mutant Miro1 lacking the ability to bind Ca(2+) prevents BDNF-induced mitochondrial presynaptic accumulation and synaptic transmission, suggesting that Miro1-mediated mitochondrial motility is involved in BDNF-induced mitochondrial presynaptic docking and neurotransmission. Together, these data suggest that mitochondrial transport and distribution play essential roles in BDNF-mediated synaptic transmission.

  13. BSA-boronic acid conjugate as lectin mimetics.

    Science.gov (United States)

    Narla, Satya Nandana; Pinnamaneni, Poornima; Nie, Huan; Li, Yu; Sun, Xue-Long

    2014-01-10

    We report bovine serum albumin (BSA)-boronic acid (BA) conjugates as lectin mimetics and their glyco-capturing capacity. The BSA-BA conjugates were synthesized by amidation of carboxylic acid groups in BSA with aminophenyl boronic acid in the presence of EDC, and were characterized by Alizarin Red S (ARS) assay and SDS-PAGE gel. The BSA-BA conjugates were immobilized onto maleimide-functionalized silica beads and their sugar capturing capacity and specificity were confirmed by ARS displacement assay. Further, surface plasmon resonance (SPR) analysis of the glyco-capturing activity of the BSA-BA conjugates was conducted by immobilizing BSA-BA onto SPR gold chip. Overall, we demonstrated a BSA-BA-based lectin mimetics for glyco-capturing applications. These lectin mimetics are expected to provide an important tool for glycomics and biosensor research and applications.

  14. (Pseudoamide-linked oligosaccharide mimetics: molecular recognition and supramolecular properties

    Directory of Open Access Journals (Sweden)

    José L. Jiménez Blanco

    2010-02-01

    Full Text Available Oligosaccharides are currently recognised as having functions that influence the entire spectrum of cell activities. However, a distinct disadvantage of naturally occurring oligosaccharides is their metabolic instability in biological systems. Therefore, much effort has been spent in the past two decades on the development of feasible routes to carbohydrate mimetics which can compete with their O-glycosidic counterparts in cell surface adhesion, inhibit carbohydrate processing enzymes, and interfere in the biosynthesis of specific cell surface carbohydrates. Such oligosaccharide mimetics are potential therapeutic agents against HIV and other infections, against cancer, diabetes and other metabolic diseases. An efficient strategy to access this type of compounds is the replacement of the glycosidic linkage by amide or pseudoamide functions such as thiourea, urea and guanidine. In this review we summarise the advances over the last decade in the synthesis of oligosaccharide mimetics that possess amide and pseudoamide linkages, as well as studies focussing on their supramolecular and recognition properties.

  15. Down-regulation of BDNF in cell and animal models increases striatal-enriched protein tyrosine phosphatase 61 (STEP61 ) levels.

    Science.gov (United States)

    Xu, Jian; Kurup, Pradeep; Azkona, Garikoitz; Baguley, Tyler D; Saavedra, Ana; Nairn, Angus C; Ellman, Jonathan A; Pérez-Navarro, Esther; Lombroso, Paul J

    2016-01-01

    Brain-derived neurotrophic factor (BDNF) regulates synaptic strengthening and memory consolidation, and altered BDNF expression is implicated in a number of neuropsychiatric and neurodegenerative disorders. BDNF potentiates N-methyl-D-aspartate receptor function through activation of Fyn and ERK1/2. STriatal-Enriched protein tyrosine Phosphatase (STEP) is also implicated in many of the same disorders as BDNF but, in contrast to BDNF, STEP opposes the development of synaptic strengthening. STEP-mediated dephosphorylation of the NMDA receptor subunit GluN2B promotes internalization of GluN2B-containing NMDA receptors, while dephosphorylation of the kinases Fyn, Pyk2, and ERK1/2 leads to their inactivation. Thus, STEP and BDNF have opposing functions. In this study, we demonstrate that manipulation of BDNF expression has a reciprocal effect on STEP61 levels. Reduced BDNF signaling leads to elevation of STEP61 both in BDNF(+/-) mice and after acute BDNF knockdown in cortical cultures. Moreover, a newly identified STEP inhibitor reverses the biochemical and motor abnormalities in BDNF(+/-) mice. In contrast, increased BDNF signaling upon treatment with a tropomyosin receptor kinase B agonist results in degradation of STEP61 and a subsequent increase in the tyrosine phosphorylation of STEP substrates in cultured neurons and in mouse frontal cortex. These findings indicate that BDNF-tropomyosin receptor kinase B signaling leads to degradation of STEP61 , while decreased BDNF expression results in increased STEP61 activity. A better understanding of the opposing interaction between STEP and BDNF in normal cognitive functions and in neuropsychiatric disorders will hopefully lead to better therapeutic strategies. Altered expression of BDNF and STEP61 has been implicated in several neurological disorders. BDNF and STEP61 are known to regulate synaptic strengthening, but in opposite directions. Here, we report that reduced BDNF signaling leads to elevation of STEP61 both in

  16. Agonistic approach of omega-3, omega-6 and its metabolites with BDNF: An in-silico study.

    Science.gov (United States)

    Kumar, Yadla Phani; Srinivas, G Sri Shanmukha; E, Yadu Mitravinda; Malla, Lalitha; Rao, Allam Appa

    2013-01-01

    Brain derived neurotrophic factor (BDNF) is a member of neurotrophic family of growth factors, mainly found in the hippocampus and cerebral cortex of brain. Studies have shown that there is a link between BDNF and cognitive dysfunction, as well as there is a relationship between the PUFAs intake and their effect on BDNF production. Intake of PUFAs, mainly omega-3 and omega-6 has show increase in production of BDNF in brain. In our study we performed docking studies on PUFAs and their metabolites with BDNF using MVD (Molegro Virtual Docker), this has shown that the metabolites of the PUFAs mainly LXA_4, NPD1, HDHA have shown more binding affinity towards BDNF. These metabolites of PUFAs are responsible for modulation of BDNF activity. PMID:24307768

  17. High-intensity interval training evokes larger serum BDNF levels compared with intense continuous exercise.

    Science.gov (United States)

    Saucedo Marquez, Cinthia Maria; Vanaudenaerde, Bart; Troosters, Thierry; Wenderoth, Nicole

    2015-12-15

    Exercise can have a positive effect on the brain by activating brain-derived neurotrophic factor (BDNF)-related processes. In healthy humans there appears to be a linear relationship between exercise intensity and the positive short-term effect of acute exercise on BDNF levels (i.e., the highest BDNF levels are reported after high-intensity exercise protocols). Here we performed two experiments to test the effectiveness of two high-intensity exercise protocols, both known to improve cardiovascular health, to determine whether they have a similar efficacy in affecting BDNF levels. Participants performed a continuous exercise (CON) protocol at 70% of maximal work rate and a high-intensity interval-training (HIT) protocol at 90% of maximal work rate for periods of 1 min alternating with 1 min of rest (both protocols lasted 20 min). We observed similar BDNF kinetics in both protocols, with maximal BDNF concentrations being reached toward the end of training (experiment 1). We then showed that both exercise protocols significantly increase BDNF levels compared with a rest condition (CON P = 0.04; HIT P high-intensity exercise for elevating serum BDNF. Additionally, 73% of the participants preferred the HIT protocol (P = 0.02). Therefore, we suggest that the HIT protocol might represent an effective and preferred intervention for elevating BDNF levels and potentially promoting brain health.

  18. Intracerebral Administration of BDNF Protects Rat Brain Against Oxidative Stress Induced by Ouabain in an Animal Model of Mania.

    Science.gov (United States)

    Valvassori, Samira S; Arent, Camila O; Steckert, Amanda V; Varela, Roger B; Jornada, Luciano K; Tonin, Paula T; Budni, Josiane; Mariot, Edemilson; Kapczinski, Flávio; Quevedo, João

    2015-08-01

    Several studies have suggested that alterations in brain-derived neurotrophic factor (BDNF) and increased oxidative stress have a central role in bipolar disorder (BD). Intracerebroventricular (ICV) injection of ouabain (OUA) in rats alters oxidative stress parameters and decreases BDNF levels in the brain. In this context, the present study aims to investigate the effects of BDNF ICV administration on BDNF levels and oxidative stress parameters in brains of rats submitted to animal model of mania induced by OUA. Wistar rats received an ICV injection of OUA, artificial cerebrospinal fluid (ACSF), OUA plus BDNF, or ACSF plus BDNF. Locomotor activity and risk-taking behavior in the rats were measured using the open-field test. In addition, we analyzed the BDNF levels and oxidative stress parameters (TBARS, Carbonyl, CAT, SOD, GR, and GPx) in the frontal cortex and hippocampus of rats. The BDNF was unable to reverse the ouabain-induced hyperactivity and risk-taking behavior. Nevertheless, BDNF treatment increased BDNF levels, modulated the antioxidant enzymes, and protected the OUA-induced oxidative damage in the brain of rats. These results suggest that BDNF alteration observed in BD patients may be associated with oxidative damage, both seen in this disorder. PMID:25164569

  19. Bio-mimetic Flow Control

    Science.gov (United States)

    Choi, Haecheon

    2009-11-01

    Bio-mimetic engineering or bio-mimetics is the application of biological methods and systems found in nature to the study and design of engineering systems and modern technology (from Wikipedia). The concept itself is old, but successful developments have been made recently, especially in the research field of flow control. The objective of flow control based on the bio-mimetic approach is to develop novel concepts for reducing drag, increasing lift and enhancing aerodynamic performance. For skin friction reduction, a few ideas have been suggested such as the riblet from shark, compliant surface from dolphin, microbubble injection and multiple front-body curvature from penguin, and V-shaped protrusion from sailfish. For form drag reduction, several new attempts have been also made recently. Examples include the V-shaped spanwise grooves from saguaro cactus, overall shape of box fish, longitudinal grooves on scallop shell, bill of swordfish, hooked comb on owl wing, trailing-edge protrusion on dragonfly wing, and fillet. For the enhancement of aerodynamic performance, focuses have been made on the birds, fish and insects: e.g., double layered feather of landing bird, leading-edge serration of humpback-whale flipper, pectoral fin of flying fish, long tail on swallowtail-butterfly wing, wing flapping motion of dragonfly, and alula in birds. Living animals adapt their bodies to better performance in multi purposes, but engineering requires single purpose in most cases. Therefore, bio-mimetic approaches often produce excellent results more than expected. However, they are sometimes based on people's wrong understanding of nature and produce unwanted results. Successes and failures from bio-mimetic approaches in flow control will be discussed in the presentation.

  20. HBpF-proBDNF: A New Tool for the Analysis of Pro-Brain Derived Neurotrophic Factor Receptor Signaling and Cell Biology

    Science.gov (United States)

    Gaub, Perrine; de Léon, Andrès; Gibon, Julien; Soubannier, Vincent; Dorval, Geneviève; Séguéla, Philippe; Barker, Philip A.

    2016-01-01

    Neurotrophins activate intracellular signaling pathways necessary for neuronal survival, growth and apoptosis. The most abundant neurotrophin in the adult brain, brain-derived neurotrophic factor (BDNF), is first synthesized as a proBDNF precursor and recent studies have demonstrated that proBDNF can be secreted and that it functions as a ligand for a receptor complex containing p75NTR and sortilin. Activation of proBDNF receptors mediates growth cone collapse, reduces synaptic activity, and facilitates developmental apoptosis of motoneurons but the precise signaling cascades have been difficult to discern. To address this, we have engineered, expressed and purified HBpF-proBDNF, an expression construct containing a 6X-HIS tag, a biotin acceptor peptide (BAP) sequence, a PreScission™ Protease cleavage site and a FLAG-tag attached to the N-terminal part of murine proBDNF. Intact HBpF-proBDNF has activities indistinguishable from its wild-type counterpart and can be used to purify proBDNF signaling complexes or to monitor proBDNF endocytosis and retrograde transport. HBpF-proBDNF will be useful for characterizing proBDNF signaling complexes and for deciphering the role of proBDNF in neuronal development, synapse function and neurodegenerative disease. PMID:26950209

  1. HBpF-proBDNF: A New Tool for the Analysis of Pro-Brain Derived Neurotrophic Factor Receptor Signaling and Cell Biology.

    Science.gov (United States)

    Gaub, Perrine; de Léon, Andrès; Gibon, Julien; Soubannier, Vincent; Dorval, Geneviève; Séguéla, Philippe; Barker, Philip A

    2016-01-01

    Neurotrophins activate intracellular signaling pathways necessary for neuronal survival, growth and apoptosis. The most abundant neurotrophin in the adult brain, brain-derived neurotrophic factor (BDNF), is first synthesized as a proBDNF precursor and recent studies have demonstrated that proBDNF can be secreted and that it functions as a ligand for a receptor complex containing p75NTR and sortilin. Activation of proBDNF receptors mediates growth cone collapse, reduces synaptic activity, and facilitates developmental apoptosis of motoneurons but the precise signaling cascades have been difficult to discern. To address this, we have engineered, expressed and purified HBpF-proBDNF, an expression construct containing a 6X-HIS tag, a biotin acceptor peptide (BAP) sequence, a PreScission™ Protease cleavage site and a FLAG-tag attached to the N-terminal part of murine proBDNF. Intact HBpF-proBDNF has activities indistinguishable from its wild-type counterpart and can be used to purify proBDNF signaling complexes or to monitor proBDNF endocytosis and retrograde transport. HBpF-proBDNF will be useful for characterizing proBDNF signaling complexes and for deciphering the role of proBDNF in neuronal development, synapse function and neurodegenerative disease. PMID:26950209

  2. Blood BDNF concentrations reflect brain-tissue BDNF levels across species

    DEFF Research Database (Denmark)

    Klein, Anders B; Williamson, Rebecca; Santini, Martin A;

    2011-01-01

    Brain-derived neurotrophic factor (BDNF) is involved in synaptic plasticity, neuronal differentiation and survival of neurons. Observations of decreased serum BDNF levels in patients with neuropsychiatric disorders have highlighted the potential of BDNF as a biomarker, but so far there have been...... no studies directly comparing blood BDNF levels to brain BDNF levels in different species. We examined blood, serum, plasma and brain-tissue BDNF levels in three different mammalian species: rat, pig, and mouse, using an ELISA method. As a control, we included an analysis of blood and brain tissue from...... conditional BDNF knockout mice and their wild-type littermates. Whereas BDNF could readily be measured in rat blood, plasma and brain tissue, it was undetectable in mouse blood. In pigs, whole-blood levels of BDNF could not be measured with a commercially available ELISA kit, but pig plasma BDNF levels (mean...

  3. Regulation of BDNF Expression by Cocaine

    OpenAIRE

    McCarthy, Deirdre M.; Brown, Amber N.; Bhide, Pradeep G.

    2012-01-01

    Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family of growth factors. It is expressed throughout the nervous system. A unique feature of the BDNF gene is the existence of multiple mRNA transcripts, all of which are translated into BDNF protein, suggesting a multilevel regulation of expression. In particular, the BDNF exon IV promoter region is a preferential target for epigenetic alterations, as it contains binding sites for CREB and MeCP2, two transcriptional reg...

  4. Chronic unpredictable stress decreases expression of brain-derived neurotrophic factor (BDNF in mouse ovaries: relationship to oocytes developmental potential.

    Directory of Open Access Journals (Sweden)

    Li-Min Wu

    Full Text Available BACKGROUND: Brain-derived neurotropic factor (BDNF was originally described in the nervous system but has been shown to be expressed in ovary tissues recently, acting as a paracrine/autocrine regulator required for developments of follicles and oocytes. Although it is generally accepted that chronic stress impairs female reproduction and decreases the expression of BDNF in limbic structures of central nervous system, which contributes to mood disorder. However, it is not known whether chronic stress affects oocytes developments, nor whether it affects expression of BDNF in ovary. METHODS: Mice were randomly assigned into control group, stressed group, BDNF-treated group and BDNF-treated stressed group. The chronic unpredictable mild stress model was used to produce psychosocial stress in mice, and the model was verified by open field test and hypothalamic-pituitary-adrenal (HPA axis activity. The methods of immunohistochemistry and western blotting were used to detect BDNF protein level and distribution. The number of retrieved oocytes, oocyte maturation, embryo cleavage and the rates of blastocyst formation after parthenogenetic activation were evaluated. RESULTS: Chronic unpredictable stress decreased the BDNF expression in antral follicles, but didn't affect the BDNF expression in primordial, primary and secondary follicles. Chronic unpredictable stress also decreased the number of retrieved oocytes and the rate of blastocyst formation, which was rescued by exogenous BDNF treatment. CONCLUSION: BDNF in mouse ovaries may be related to the decreased number of retrieved oocytes and impaired oocytes developmental potential induced by chronic unpredictable stress.

  5. Systemic delivery of recombinant brain derived neurotrophic factor (BDNF in the R6/2 mouse model of Huntington's disease.

    Directory of Open Access Journals (Sweden)

    Carmela Giampà

    Full Text Available Loss of huntingtin-mediated BDNF gene transcription has been shown to occur in HD and thus contribute to the degeneration of the striatum. Several studies have indicated that an increase in BDNF levels is associated with neuroprotection and amelioration of neurological signs in animal models of HD. In a recent study, an increase in BDNF mRNA and protein levels was recorded in mice administered recombinant BDNF peripherally. Chronic, indwelling osmotic mini-pumps containing either recombinant BDNF or saline were surgically placed in R6/2 or wild-type mice from 4 weeks of age until euthanasia. Neurological evaluation (paw clasping, rotarod performance, locomotor activity in an open field was performed. After transcardial perfusion, histological and immunohistochemical studies were performed. We found that BDNF- treated R6/2 mice survived longer and displayed less severe signs of neurological dysfunction than the vehicle treated ones. Primary outcome measures such as brain volume, striatal atrophy, size and morphology of striatal neurons, neuronal intranuclear inclusions and microglial reaction confirmed a neuroprotective effect of the compound. BDNF was effective in increasing significantly the levels of activated CREB and of BDNF the striatal spiny neurons. Moreover, systemically administered BDNF increased the synthesis of BDNF as demonstrated by RT-PCR, and this might account for the beneficial effects observed in this model.

  6. Systemic delivery of recombinant brain derived neurotrophic factor (BDNF) in the R6/2 mouse model of Huntington's disease.

    Science.gov (United States)

    Giampà, Carmela; Montagna, Elena; Dato, Clemente; Melone, Mariarosa A B; Bernardi, Giorgio; Fusco, Francesca Romana

    2013-01-01

    Loss of huntingtin-mediated BDNF gene transcription has been shown to occur in HD and thus contribute to the degeneration of the striatum. Several studies have indicated that an increase in BDNF levels is associated with neuroprotection and amelioration of neurological signs in animal models of HD. In a recent study, an increase in BDNF mRNA and protein levels was recorded in mice administered recombinant BDNF peripherally. Chronic, indwelling osmotic mini-pumps containing either recombinant BDNF or saline were surgically placed in R6/2 or wild-type mice from 4 weeks of age until euthanasia. Neurological evaluation (paw clasping, rotarod performance, locomotor activity in an open field) was performed. After transcardial perfusion, histological and immunohistochemical studies were performed. We found that BDNF- treated R6/2 mice survived longer and displayed less severe signs of neurological dysfunction than the vehicle treated ones. Primary outcome measures such as brain volume, striatal atrophy, size and morphology of striatal neurons, neuronal intranuclear inclusions and microglial reaction confirmed a neuroprotective effect of the compound. BDNF was effective in increasing significantly the levels of activated CREB and of BDNF the striatal spiny neurons. Moreover, systemically administered BDNF increased the synthesis of BDNF as demonstrated by RT-PCR, and this might account for the beneficial effects observed in this model.

  7. The testosterone mimetic properties of icariin

    Institute of Scientific and Technical Information of China (English)

    Zhen-Bao Zhang; Qing-Tao Yang

    2006-01-01

    Aim: To evaluate the testosterone mimetic properties of icariin. Methods: Forty-eight healthy male Sprague-Dawley rats at the age of 15 months were randomly divided into four groups with 12 rats each: the control group (C), the model group (M), the icariin group (ICA) and the testosterone group (T). The reproductive system was damaged by cyclogroup for 7 consecutive days, respectively. The levels of serum testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), serum bone Gla-protein (BGP) and tartrate-resistant acid phosphatase activity in serum (StrACP) were determined. The histological changes of the testis and the penis were observed by microscope with hematoxylin-eosin (HE) staining and terminal deoxynucleotidyl transferase biotin-dUTP-X nick end labeling (TUNEL),respectively. Results: (1) Icariin improved the condition of reproductive organs and increased the circulating levels of testosterone. (2) Icariin treatment also improved the steady-state serum BGP and might have promoted bone formation. At the same time, it decreased the serum levels of StrACP and might have reduced the bone resorption. (3)Icarrin suppressed the extent of apoptosis of penile cavernosal smooth muscle cells. Conclusion: Icariin has testosterone mimetic properties and has therapeutic potential in the management of hypoandrogenism.

  8. BDNF Val66Met polymorphism and protein levels in Amniotic Fluid

    Directory of Open Access Journals (Sweden)

    Calabrese Francesca

    2010-02-01

    Full Text Available Abstract Background Brain-Derived Neurotrophic Factor (BDNF is a neurotrophin which plays survival- and growth-promoting activity in neuronal cells and it is involved in cellular plasticity mechanisms as it controls activity dependent synaptic transmission. A functional polymorphism (Val66Met in the pro-region of BDNF, which affects the intracellular trafficking of proBDNF has been associated with memory and cognitive deficits as well as to an increased susceptibility for several psychiatric disorders especially those with a neurodevelopmental origin. To date, no study has evaluated the influence of the Val66Met polymorphism on BDNF levels in a peripheral system that may reflect fetal neurodevelopment. Therefore we investigated in amniotic fluids (AF obtained from 139 healthy women during 15-17 week of pregnancy, BDNF protein levels in correlation with the Val66Met polymorphism. Results Interestingly we found a significant BDNF protein levels reduction in 55 Met carriers (Val/Met and Met/Met (p = 0.002 as compared to 84 non carriers (Val/Val, and no effect of fetus gender, maternal age or gestation week on BDNF levels has been observed. Conclusion These results, although explorative, indicate that during fetal life the Val66Met genotype might influences BDNF protein levels in AF supporting the involvement of this polymorphism in behavioral and functional brain individual differences in the adulthood.

  9. Association of testosterone and BDNF serum levels with craving during alcohol withdrawal.

    Science.gov (United States)

    Heberlein, Annemarie; Lenz, Bernd; Opfermann, Birgitt; Gröschl, Michael; Janke, Eva; Stange, Katrin; Groh, Adrian; Kornhuber, Johannes; Frieling, Helge; Bleich, Stefan; Hillemacher, Thomas

    2016-08-01

    Preclinical and clinical studies show associations between testosterone and brain-derived neurotrophic growth factor (BDNF) serum levels. BDNF and testosterone have been independently reported to influence alcohol consumption. Therefore, we aimed to investigate a possible interplay of testosterone and BDNF contributing to alcohol dependence. Regarding possible interplay of testosterone and BDNF and the activity of the hypothalamic pituitary axis (HPA), we included cortisol serum levels in our research. We investigated testosterone and BDNF serum levels in a sample of 99 male alcohol-dependent patients during alcohol withdrawal (day 1, 7, and 14) and compared them to a healthy male control group (n = 17). The testosterone serum levels were significantly (p < 0.001) higher in the patients' group than in the control group and decreased significantly during alcohol withdrawal (p < 0.001). The decrease of testosterone serum levels during alcohol withdrawal (days 1-7) was significantly associated with the BDNF serum levels (day 1: p = 0.008). In a subgroup of patients showing high cortisol serum levels (putatively mirroring high HPA activity), we found a significant association of BDNF and testosterone as well as with alcohol craving measured by the Obsessive and Compulsive Drinking Scale (OCDS). Our data suggest a possible association of BDNF and testosterone serum levels, which may be relevant for the symptomatology of alcohol dependence. Further studies are needed to clarify our results. PMID:27514572

  10. Cooperation between BDNF and glutamate in the regulation of synaptic transmission and neuronal development.

    Science.gov (United States)

    Martin, Jean-Luc; Finsterwald, Charles

    2011-01-01

    Ample evidence supports a role of brain-derived neurotrophic factor (BDNF) in the survival and differentiation of selective populations of neurons in the peripheral and central nervous systems. In addition to its trophic actions, BDNF exerts acute effects on synaptic transmission and plasticity. In particular, BDNF enhances excitatory synaptic transmission through pre- and postsynaptic mechanisms. In this regard, BDNF enhances glutamate release, the frequency of miniature excitatory postsynaptic currents (mEPSCs), NMDA receptor activity and the phosphorylation of NMDA receptor subunits. Our recent studies revealed a novel cooperative interaction between BDNF and glutamate in the regulation of dendritic development. Indeed, we found that the effects of BDNF on dendritic growth of cortical neurons require both the stimulation of cAMP response element-binding protein (CREB) phosphorylation by BDNF and the activation of the CREB-regulated transcription coactivator 1 (CRTC1) by glutamate. Together, these studies highlight the importance of the cooperation between BDNF and glutamate in the regulation of synaptic transmission and neuronal development.

  11. Many Faces of Mimetic Gravity

    CERN Document Server

    Hammer, Katrin

    2015-01-01

    We consider the recently introduced mimetic gravity, which is a Weyl-symmetric extension of the General Relativity and which can play a role of an imperfect fluid-like Dark Matter with a small sound speed. In this paper we discuss in details how this higher- derivative scalar-tensor theory goes beyond the construction by Horndeski, keeping only one scalar degree of freedom on top of two standard graviton polarizations. In particular, we consider representations of the theory in different sets of Weyl-invariant variables and connect this framework to the singular Brans-Dicke theory. Further, we find solution of equations of motion for the mimetic gravity in the synchronous reference frame in a general curved spacetime. This solution is exact in the test-field approximation or in the case of a shear-free spacetime without any other matter.

  12. Mimetic orthosis for lower limbs to be applied on rehabilitation for hemiplegic persons

    OpenAIRE

    P.S. Luna; E. Cardiel; R. Muñoz; Urrutia, R.; Villanueva, D.; P.R.Hernández

    2008-01-01

    A rehabilitation tool based on an innovative mimetic active orthosis for hemiplegics is presented. It follows concepts of neuronal learning from afferent information from movements, similar to those lost after brain damage. An artificial gait pattern is applied on knee and hip articulations of a functional modified limb by using an exoskeleton powered by pneumatic muscles. Key Words: Key Words: Key Words: Key Words: Key Words: Active orthosis, mimetic orthosis, gait rehabilitation.

  13. Cleavage of proBDNF by tPA/plasmin is essential for long-term hippocampal plasticity.

    Science.gov (United States)

    Pang, Petti T; Teng, Henry K; Zaitsev, Eugene; Woo, Newton T; Sakata, Kazuko; Zhen, Shushuang; Teng, Kenneth K; Yung, Wing-Ho; Hempstead, Barbara L; Lu, Bai

    2004-10-15

    Long-term memory is thought to be mediated by protein synthesis-dependent, late-phase long-term potentiation (L-LTP). Two secretory proteins, tissue plasminogen activator (tPA) and brain-derived neurotrophic factor (BDNF), have been implicated in this process, but their relationship is unclear. Here we report that tPA, by activating the extracellular protease plasmin, converts the precursor proBDNF to the mature BDNF (mBDNF), and that such conversion is critical for L-LTP expression in mouse hippocampus. Moreover, application of mBDNF is sufficient to rescue L-LTP when protein synthesis is inhibited, which suggests that mBDNF is a key protein synthesis product for L-LTP expression.

  14. Blood BDNF concentrations reflect brain-tissue BDNF levels across species

    DEFF Research Database (Denmark)

    Klein, Anders B; Williamson, Rebecca; Santini, Martin A;

    2011-01-01

    Brain-derived neurotrophic factor (BDNF) is involved in synaptic plasticity, neuronal differentiation and survival of neurons. Observations of decreased serum BDNF levels in patients with neuropsychiatric disorders have highlighted the potential of BDNF as a biomarker, but so far there have been...... no studies directly comparing blood BDNF levels to brain BDNF levels in different species. We examined blood, serum, plasma and brain-tissue BDNF levels in three different mammalian species: rat, pig, and mouse, using an ELISA method. As a control, we included an analysis of blood and brain tissue from...

  15. Exogenous t-PA administration increases hippocampal mature BDNF levels. plasmin- or NMDA-dependent mechanism?

    Science.gov (United States)

    Rodier, Marion; Prigent-Tessier, Anne; Béjot, Yannick; Jacquin, Agnès; Mossiat, Claude; Marie, Christine; Garnier, Philippe

    2014-01-01

    Brain-derived neurotrophic factor (BDNF) through TrkB activation is central for brain functioning. Since the demonstration that plasmin is able to process pro-BDNF to mature BDNF and that these two forms have opposite effects on neuronal survival and plasticity, a particular attention has been paid to the link between tissue plasminogen activator (tPA)/plasmin system and BDNF metabolism. However, t-PA via its action on different N-methyl-D-aspartate (NMDA) receptor subunits is also considered as a neuromodulator of glutamatergic transmission. In this context, the aim of our study was to investigate the effect of recombinant (r)t-PA administration on brain BDNF metabolism in rats. In the hippocampus, we found that rt-PA (10 mg/kg) administration induced a progressive increase in mature BDNF levels associated with TrkB activation. In order to delineate the mechanistic involved, plasmin activity was assessed and its inhibition was attempted using tranexamic acid (30 or 300 mg/kg, i.v.) while NMDA receptors were antagonized with MK801 (0.3 or 3 mg/kg, i.p.) in combination with rt-PA treatment. Our results showed that despite a rise in rt-PA activity, rt-PA administration failed to increase hippocampal plasmin activity suggesting that the plasminogen/plasmin system is not involved whereas MK801 abrogated the augmentation in mature BDNF levels observed after rt-PA administration. All together, our results show that rt-PA administration induces increase in hippocampal mature BDNF expression and suggests that rt-PA contributes to the control of brain BDNF synthesis through a plasmin-independent potentiation of NMDA receptors signaling.

  16. Exogenous t-PA administration increases hippocampal mature BDNF levels. plasmin- or NMDA-dependent mechanism?

    Directory of Open Access Journals (Sweden)

    Marion Rodier

    Full Text Available Brain-derived neurotrophic factor (BDNF through TrkB activation is central for brain functioning. Since the demonstration that plasmin is able to process pro-BDNF to mature BDNF and that these two forms have opposite effects on neuronal survival and plasticity, a particular attention has been paid to the link between tissue plasminogen activator (tPA/plasmin system and BDNF metabolism. However, t-PA via its action on different N-methyl-D-aspartate (NMDA receptor subunits is also considered as a neuromodulator of glutamatergic transmission. In this context, the aim of our study was to investigate the effect of recombinant (rt-PA administration on brain BDNF metabolism in rats. In the hippocampus, we found that rt-PA (10 mg/kg administration induced a progressive increase in mature BDNF levels associated with TrkB activation. In order to delineate the mechanistic involved, plasmin activity was assessed and its inhibition was attempted using tranexamic acid (30 or 300 mg/kg, i.v. while NMDA receptors were antagonized with MK801 (0.3 or 3 mg/kg, i.p. in combination with rt-PA treatment. Our results showed that despite a rise in rt-PA activity, rt-PA administration failed to increase hippocampal plasmin activity suggesting that the plasminogen/plasmin system is not involved whereas MK801 abrogated the augmentation in mature BDNF levels observed after rt-PA administration. All together, our results show that rt-PA administration induces increase in hippocampal mature BDNF expression and suggests that rt-PA contributes to the control of brain BDNF synthesis through a plasmin-independent potentiation of NMDA receptors signaling.

  17. BDNF in sleep, insomnia, and sleep deprivation.

    Science.gov (United States)

    Schmitt, Karen; Holsboer-Trachsler, Edith; Eckert, Anne

    2016-01-01

    The protein brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family of growth factors involved in plasticity of neurons in several brain regions. There are numerous evidence that BDNF expression is decreased by experiencing psychological stress and that, accordingly, a lack of neurotrophic support causes major depression. Furthermore, disruption in sleep homeostatic processes results in higher stress vulnerability and is often associated with stress-related mental disorders. Recently, we reported, for the first time, a relationship between BDNF and insomnia and sleep deprivation (SD). Using a biphasic stress model as explanation approach, we discuss here the hypothesis that chronic stress might induce a deregulation of the hypothalamic-pituitary-adrenal system. In the long-term it leads to sleep disturbance and depression as well as decreased BDNF levels, whereas acute stress like SD can be used as therapeutic intervention in some insomniac or depressed patients as compensatory process to normalize BDNF levels. Indeed, partial SD (PSD) induced a fast increase in BDNF serum levels within hours after PSD which is similar to effects seen after ketamine infusion, another fast-acting antidepressant intervention, while traditional antidepressants are characterized by a major delay until treatment response as well as delayed BDNF level increase. Key messages Brain-derived neurotrophic factor (BDNF) plays a key role in the pathophysiology of stress-related mood disorders. The interplay of stress and sleep impacts on BDNF level. Partial sleep deprivation (PSD) shows a fast action on BDNF level increase. PMID:26758201

  18. BDNF regulates the expression and distribution of vesicular glutamate transporters in cultured hippocampal neurons.

    Directory of Open Access Journals (Sweden)

    Carlos V Melo

    Full Text Available BDNF is a pro-survival protein involved in neuronal development and synaptic plasticity. BDNF strengthens excitatory synapses and contributes to LTP, presynaptically, through enhancement of glutamate release, and postsynaptically, via phosphorylation of neurotransmitter receptors, modulation of receptor traffic and activation of the translation machinery. We examined whether BDNF upregulated vesicular glutamate receptor (VGLUT 1 and 2 expression, which would partly account for the increased glutamate release in LTP. Cultured rat hippocampal neurons were incubated with 100 ng/ml BDNF, for different periods of time, and VGLUT gene and protein expression were assessed by real-time PCR and immunoblotting, respectively. At DIV7, exogenous application of BDNF rapidly increased VGLUT2 mRNA and protein levels, in a dose-dependent manner. VGLUT1 expression also increased but only transiently. However, at DIV14, BDNF stably increased VGLUT1 expression, whilst VGLUT2 levels remained low. Transcription inhibition with actinomycin-D or α-amanitine, and translation inhibition with emetine or anisomycin, fully blocked BDNF-induced VGLUT upregulation. Fluorescence microscopy imaging showed that BDNF stimulation upregulates the number, integrated density and intensity of VGLUT1 and VGLUT2 puncta in neurites of cultured hippocampal neurons (DIV7, indicating that the neurotrophin also affects the subcellular distribution of the transporter in developing neurons. Increased VGLUT1 somatic signals were also found 3 h after stimulation with BDNF, further suggesting an increased de novo transcription and translation. BDNF regulation of VGLUT expression was specifically mediated by BDNF, as no effect was found upon application of IGF-1 or bFGF, which activate other receptor tyrosine kinases. Moreover, inhibition of TrkB receptors with K252a and PLCγ signaling with U-73122 precluded BDNF-induced VGLUT upregulation. Hippocampal neurons express both isoforms during

  19. Respective pharmacological features of neuropathic-like pain evoked by intrathecal BDNF versus sciatic nerve ligation in rats.

    Science.gov (United States)

    M'Dahoma, Saïd; Barthélemy, Sandrine; Tromilin, Claire; Jeanson, Tiffany; Viguier, Florent; Michot, Benoit; Pezet, Sophie; Hamon, Michel; Bourgoin, Sylvie

    2015-11-01

    Numerous reported data support the idea that Brain Derived Neurotrophic Factor (BDNF) is critically involved in both depression and comorbid pain. The possible direct effect of BDNF on pain mechanisms was assessed here and compared with behavioral/neurobiological features of neuropathic pain caused by chronic constriction injury to the sciatic nerve (CCI-SN). Sprague-Dawley male rats were either injected intrathecally with BDNF (3.0 ng i.t.) or subjected to unilateral CCI-SN. Their respective responses to anti-hyperalgesic drugs were assessed using the Randall-Selitto test and both immunohistochemical and RT-qPCR approaches were used to investigate molecular/cellular mechanisms underlying hyperalgesia in both models. Long lasting hyperalgesia and allodynia were induced by i.t. BDNF in intact healthy rats like those found after CCI-SN. Acute treatment with the BDNF-TrkB receptor antagonist cyclotraxin B completely prevented i.t. BDNF-induced hyperalgesia and partially reversed this symptom in both BDNF-pretreated and CCI-SN lesioned rats. Acute administration of the anticonvulsant pregabalin, the NMDA receptor antagonist ketamine, the opioid analgesics morphine and tapentadol or the antidepressant agomelatine also transiently reversed hyperalgesia in both i.t. BDNF injected- and CCI-SN lesioned-rats. Marked induction of microglia activation markers (OX42, Iba1, P-p38), proinflammatory cytokine IL-6, NMDA receptor subunit NR2B and BDNF was found in spinal cord and/or dorsal root ganglia of CCI-SN rats. A long lasting spinal BDNF overexpression was also observed in BDNF i.t. rats, indicating an autocrine self-induction, with downstream long lasting TrkB-mediated neuropathic-like pain. Accordingly, TrkB blockade appeared as a relevant approach to alleviate not only i.t. BDNF- but also nerve lesion-evoked neuropathic pain. PMID:26343858

  20. Hippocampal BDNF signaling restored with chronic asiaticoside treatment in depression-like mice.

    Science.gov (United States)

    Luo, Liu; Liu, Xiao-Long; Mu, Rong-Hao; Wu, Yong-Jing; Liu, Bin-Bin; Geng, Di; Liu, Qing; Yi, Li-Tao

    2015-05-01

    Brain-derived neurotrophic factor (BDNF) plays a key role in the regulation of depression in the brain. Recently, increasing studies have focused on the antidepressant-like mechanism of BDNF and its downstream signaling pathway. A previous study has shown that asiaticoside produced an antidepressant-like action in the mouse tail suspension test and forced swimming test. However, the neurotrophic mechanism that is affected by asiaticoside is unclear. Our present study aimed to verify whether asiaticoside produces an antidepressant-like effect through the activation of BDNF signaling in chronic unpredictable mild stress (CUMS). The results showed that mice treated with asiaticoside for four weeks reversed the decreased sucrose preference and increased immobility time that was observed in CUMS mice. In addition, we found that asiaticoside up-regulated BDNF, PSD-95 and synapsin I expression only in the hippocampus but not in the frontal cortex in both non-stressed and CUMS mice. However, K252a, an inhibitor of BDNF receptor tropomyosin-related kinase receptor B (TrkB), completely abolished the antidepressant-like effect of asiaticoside. Moreover, the expression of hippocampal BDNF, PSD-95 and synapsin I that had increased with asiaticoside also declined with K252a pretreatment. In conclusion, our study implies that it is possible that asiaticoside exerts its antidepressant-like action by activating BDNF signaling in the hippocampus.

  1. PACAP enhances axon outgrowth in cultured hippocampal neurons to a comparable extent as BDNF.

    Directory of Open Access Journals (Sweden)

    Katsuya Ogata

    Full Text Available Pituitary adenylate cyclase-activating polypeptide (PACAP exerts neurotrophic activities including modulation of synaptic plasticity and memory, hippocampal neurogenesis, and neuroprotection, most of which are shared with brain-derived neurotrophic factor (BDNF. Therefore, the aim of this study was to compare morphological effects of PACAP and BDNF on primary cultured hippocampal neurons. At days in vitro (DIV 3, PACAP increased neurite length and number to similar levels by BDNF, but vasoactive intestinal polypeptide showed much lower effects. In addition, PACAP increased axon, but not dendrite, length, and soma size at DIV 3 similarly to BDNF. The PACAP antagonist PACAP6-38 completely blocked the PACAP-induced increase in axon, but not dendrite, length. Interestingly, the BDNF-induced increase in axon length was also inhibited by PACAP6-38, suggesting a mechanism involving PACAP signaling. K252a, a TrkB receptor inhibitor, inhibited axon outgrowth induced by PACAP and BDNF without affecting dendrite length. These results indicate that in primary cultured hippocampal neurons, PACAP shows morphological actions via its cognate receptor PAC1, stimulating neurite length and number, and soma size to a comparable extent as BDNF, and that the increase in total neurite length is ascribed to axon outgrowth.

  2. Fear extinction and BDNF: translating animal models of PTSD to the clinic.

    Science.gov (United States)

    Andero, R; Ressler, K J

    2012-07-01

    Brain-derived neurotrophic factor (BDNF) is the most studied neurotrophin involved in synaptic plasticity processes that are required for long-term learning and memory. Specifically, BDNF gene expression and activation of its high-affinity tropomyosin-related kinase B (TrkB) receptor are necessary in the amygdala, hippocampus and prefrontal cortex for the formation of emotional memories, including fear memories. Among the psychiatric disorders with altered fear processing, there is post-traumatic stress disorder (PTSD) which is characterized by an inability to extinguish fear memories. Since BDNF appears to enhance extinction of fear, targeting impaired extinction in anxiety disorders such as PTSD via BDNF signalling may be an important and novel way to enhance treatment efficacy. The aim of this review is to provide a translational point of view that stems from findings in the BDNF regulation of synaptic plasticity and fear extinction. In addition, there are different systems that seem to alter fear extinction through BDNF modulation like the endocannabinoid system and the hypothalamic-pituitary adrenal axis. Recent work also finds that the pituitary adenylate cyclase-activating polypeptide and PAC1 receptor, which are upstream of BDNF activation, may be implicated in PTSD. Especially interesting are data that exogenous fear extinction enhancers such as antidepressants, histone deacetylases inhibitors and D-cycloserine, a partial N-methyl d-aspartate agonist, may act through or in concert with the BDNF-TrkB system. Finally, we review studies where recombinant BDNF and a putative TrkB agonist, 7,8-dihydroxyflavone, may enhance extinction of fear. These approaches may lead to novel agents that improve extinction in animal models and eventually humans. PMID:22530815

  3. A Novel Peptide Thrombopoietin Mimetic Designing and Optimization Using Computational Approach.

    Science.gov (United States)

    Singh, Vimal Kishor; Kumar, Neeraj; Kalsan, Manisha; Saini, Abhishek; Chandra, Ramesh

    2016-01-01

    Thrombopoietin receptor (TPOR) is a cytokine receptor protein present on the cell surface. The activation of TPOR by thrombopoietin (TPO) (a glycoprotein hormone) triggers an intracellular cascade of megakaryocytopoiesis for the formation of platelets. Recent studies on ex vivo megakaryocytopoiesis have evolved the possibilities of therapeutics uses. These findings have paved the way for the development of various TPO alternatives (recombinant TPO, peptide, and non-peptide TPO mimetics), which are useful in regenerative medicine. However, these alternatives possess various limitations such as induction of autoimmune effects, high production cost, low specificity, and hence activity. In the present study, a novel peptidic TPO mimetic was designed through computational studies by studying the binding sites of TPO and TMP to TPOR and analogs of known mimetics. Screening of combinatorial library was done through molecular docking using ClusPro. These studies indicated mimetic-9 as a significant molecule since it was found to have better binding score of -938.8 kcal/mol with seven hydrogen bonds and a high number of hydrophobic interactions, than known mimetic TMP with docking score of -798.4 kcal/mol and TMP dimer with docking score of -811.9 kcal/mol for TPOR. Mimetic9-TPOR complex was further assessed by the molecular dynamics simulation, and their complex was found to be stable with an RMSD value of 0.091 Å. While studying the parameters, mimetic-9 was found to have overall good physiochemical properties with positive grand average hydropathy (GRAVY) score and high instability index score and was found to be localized in the extracellular region. The designed mimetic-9 might prove to be a useful lead molecule for mimicking the role of TPO for in vitro platelet production with higher efficiency. PMID:27630985

  4. Regulation of BDNF expression by cocaine.

    Science.gov (United States)

    McCarthy, Deirdre M; Brown, Amber N; Bhide, Pradeep G

    2012-12-01

    Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family of growth factors. It is expressed throughout the nervous system. A unique feature of the BDNF gene is the existence of multiple mRNA transcripts, all of which are translated into BDNF protein, suggesting a multilevel regulation of expression. In particular, the BDNF exon IV promoter region is a preferential target for epigenetic alterations, as it contains binding sites for CREB and MeCP2, two transcriptional regulators known to mediate epigenetic changes. Exposure to drugs of abuse is known to modulate epigenetic regulation of BDNF gene expression. This review will discuss how exposure to cocaine, one of the most addictive drugs known to mankind, can produce alterations in BDNF gene expression, especially in the mesolimbic dopaminergic system, which lead to alterations in the reward-mediated behaviors involved in addiction. PMID:23239946

  5. Genipin is active via modulating monoaminergic transmission and levels of brain-derived neurotrophic factor (BDNF) in rat model of depression.

    Science.gov (United States)

    Wang, Q-S; Tian, J-S; Cui, Y-L; Gao, S

    2014-09-01

    Genipin, an important bioactive component from Gardenia jasminoides Eills, was demonstrated to possess antidepressant-like effects in a previous study. However, the molecular mechanism of antidepressant-like effects on genipin was not clear. The present study aimed to investigate the possible mechanism of antidepressant-like effects on genipin with a chronic unpredictable mild stress (CUMS)-induced depression model in rats. In CUMS-induced depressive rats, bodyweight and 1% sucrose consumption decreased significantly compared with the normal control group. Furthermore, these changes could be significantly reversed by genipin application. The levels of 5-hydroxytryptamine (5-HT), norepinephrine (NE) in the hippocampus decreased and the level of 5-hydroxyindole acetic acid (5-HIAA) increased in the CUMS-induced depressive rats. However, pre-treatments with genipin significantly increased the levels of 5-HT, NE and decreased the level of 5-HIAA in the hippocampus. The concentration of cAMP in the hippocampus was increased by genipin compared to the CUMS-exposed model group. The mRNA expressions of 5-hydroxytryptamine 1A receptor (5-HT1AR), cAMP response element binding protein (CREB) and brain-derived neurotrophic factor (BDNF) in rats were decreased exposed to CUMS, which were reversed by genipin-treated rats exposed to CUMS. Compared to the CUMS-exposed model group, the mRNA expression of 5-hydroxytryptamine 2A receptor (5-HT(2A)R) was decreased significantly by genipin-treated rats. The mRNA and protein expression of CREB, BDNF were increased in genipin-treated rats compared to the CUMS-exposed model group. Moreover, the levels of corticosterone in serum were decreased by genipin-treated compared to the CUMS-exposed model group. These results suggest that the possible mechanism of antidepressant-like effects on genipin, at least in one part, resulted from monoaminergic neurotransmitter system and the potential dysfunctional regulation of the post-receptor signaling

  6. Association Between Smoking, Nicotine Dependence, and BDNF Val(66)Met Polymorphism with BDNF Concentrations in Serum

    NARCIS (Netherlands)

    Jamal, Mumtaz; Van der Does, Willem; Elzinga, Bernet M.; Molendijk, Marc L.; Penninx, Brenda W. J. H.

    2015-01-01

    Introduction: Nicotine use is associated with the upregulation of brain-derived neurotrophic factor (BDNF) in serum. An association between smoking and the BDNF Val(66)Met polymorphism has also been found. The aim of this study is to examine the levels of serum BDNF in never-smokers, former smokers,

  7. Bradykinin antagonists modified with dipeptide mimetic beta-turn inducers.

    Science.gov (United States)

    Alcaro, Maria C; Vinci, Valerio; D'Ursi, Anna M; Scrima, Mario; Chelli, Mario; Giuliani, Sandro; Meini, Stefania; Di Giacomo, Marcello; Colombo, Lino; Papini, Anna Maria

    2006-05-01

    Bradykinin (BK) is involved in a wide variety of pathophysiological processes. Potent BK peptide antagonists can be developed introducing constrained unnatural amino acids, necessary to force the secondary structure of the molecule. In this paper, we report a structure-activity relationship study of two peptide analogues of the potent B2 antagonist HOE 140 by replacing the D-Tic-Oic dipeptide with conformationally constrained dipeptide mimetic beta-turn inducers. PMID:16504505

  8. Increased serum brain-derived neurotrophic factor (BDNF) levels in patients with narcolepsy

    DEFF Research Database (Denmark)

    Klein, Anders B; Jennum, Poul; Knudsen, Stine;

    2013-01-01

    in hypocretin neurons in hypothalamus in post-mortem tissue. Brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are important for activity-dependent neuronal function and synaptic modulation and it is considered that these mechanisms are important in sleep regulation. We hypothesised...... that serum levels of these factors are altered in patients with narcolepsy compared to healthy controls without sleep disturbances. Polysomnography data was obtained and serum BDNF and NGF levels measured using ELISA, while hypocretin was measured using RIA. Serum BDNF levels were significantly higher...

  9. THE GENE EXPRESSION OF BDNF IN NORMAL RABBIT RETINA

    Institute of Scientific and Technical Information of China (English)

    王建明; 胡海涛; 马东亮; 孙乃学; 赵世平; 冯海晓

    2004-01-01

    Objective To investigate the distribution of brain-derived neurotrophic factor(BDNF) protein in the rabbit retina. Methods Immune response material in the retina was observed using BDNF antibody by the method of immunohistochemistry. Results BDNF gene expression was mainly found in the RGCs, also in innernuclei cells and outernuclei cells in rabbit retina. Conclusion RGC is not only the target cell of BDNF, but also express the BDNF protein. BDNF from multi-sources participates in the regulation of RGCs.

  10. BDNF/TrkB Signaling as a Potential Novel Target in Pediatric Brain Tumors: Anticancer Activity of Selective TrkB Inhibition in Medulloblastoma Cells.

    Science.gov (United States)

    Thomaz, Amanda; Jaeger, Mariane; Buendia, Marienela; Bambini-Junior, Victorio; Gregianin, Lauro José; Brunetto, Algemir Lunardi; Brunetto, André T; de Farias, Caroline Brunetto; Roesler, Rafael

    2016-07-01

    Medulloblastoma (MB) is the most common malignant pediatric brain tumor. Deregulation of brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) signaling has been associated with increased proliferative capabilities, invasiveness, and chemoresistance in several types of cancer. However, the relevance of this pathway in MB remains unknown. Here, we show that the selective TrkB inhibitor N-[2-[[(hexahydro-2-oxo-1H-azepin-3-yl)amino]carbonyl]phenyl]-benzo[b]thiophene-2-carboxamide (ANA-12) markedly reduced the viability and survival of human cell lines representative of different MB molecular subgroups. These findings provide the first evidence supporting further investigation of TrkB inhibition as a potential novel strategy for MB treatment. PMID:26614346

  11. Neuroticism, depressive symptoms, and serum BDNF

    Science.gov (United States)

    Terracciano, Antonio; Lobina, Monia; Piras, Maria Grazia; Mulas, Antonella; Cannas, Alessandra; Meirelles, Osorio; Sutin, Angelina R.; Zonderman, Alan B; Uda, Manuela; Crisponi, Laura; Schlessinger, David

    2011-01-01

    Objective Animal models and clinical studies suggest that brain-derived neurotrophic factor (BDNF) is involved in the pathophysiology of depression. We test whether serum and plasma levels of BDNF are associated with trait Neuroticism and its facets, and with state measure of depressive symptoms. Method In a community-based cohort (N = 2099) we measured serum and plasma BDNF concentration, administered the Revised NEO Personality Inventory (NEO-PI-R) and the Center for Epidemiologic Studies Depression Scale (CES-D). Covariates included age, sex, cigarette smoking, obesity, and antidepressant use. Results Serum BDNF concentrations were inversely related to Neuroticism (r = −0.074, P < 0.001), in particular the Depression facet (r = −0.08, P < 0.001). Lower BDNF concentrations were also associated with severe depressive symptoms (CES-D ≥ 28; OR = 0.906; 95%CI = 0.851–0.965). The association of serum BDNF with Neuroticism was independent of depressive symptoms, indicating that serum BDNF might represent a biological correlate of Neuroticism and not just of transient depressive states. Plasma BDNF was not associated with measures of depression. Conclusions Our study suggests that lower serum BDNF is associated with both a dispositional vulnerability to depression and acute depressive states in the general population. PMID:21949427

  12. Hippocampal BDNF content in response to short- and long-term exercise.

    Science.gov (United States)

    Sheikhzadeh, Farzam; Etemad, Asieh; Khoshghadam, Sahar; Asl, Naser Ahmadi; Zare, Peyman

    2015-07-01

    The hippocampus is a region in the brain that is crucial for learning and memory. Previous researches proved that brain-derived neurotrophic factor (BDNF) is a probable responsible protein in the learning and memory formation process. BDNF content is thought to be affected by environmental enrichment and physical activity. The purpose of this research was to identify the effect of short- and long-term forced exercise on hippocampal BDNF levels. A total of 30 Wistar rats were randomly divided into three groups (control, short-term exercise and long-term exercise) and treated by treadmill running based on their group. As the treadmill running period finished, the animals were anesthetized. The hippocampus was dissected out immediately and BDNF content of the samples was assessed by ELISA. None of the exercise paradigms did make any significant change on hippocampal BDNF levels. Although exercise was proposed to up-regulate BDNF levels, these results show that the intensity or the duration of running paradigm used in forced exercise protocols here was not enough to affect BDNF levels in the hippocampus significantly. PMID:25860428

  13. Unimodular mimetic F(R) inflation

    Science.gov (United States)

    Odintsov, S. D.; Oikonomou, V. K.

    2016-07-01

    We propose the unimodular-mimetic F(R) gravity theory, to resolve cosmological constant problem and dark matter problem in a unified geometric manner. We demonstrate that such a theory naturally admits accelerating universe evolution. Furthermore, we construct unimodular-mimetic F(R) inflationary cosmological scenarios compatible with the Planck and BICEP2/Keck-Array observational data. We also address the graceful exit issue, which is guaranteed by the existence of unstable de Sitter vacua.

  14. Multiple faces of BDNF in cocaine addiction

    Science.gov (United States)

    Li, Xuan; Wolf, Marina E.

    2014-01-01

    Brain-derived neurotrophic factor (BDNF) has been found to play roles in many types of plasticity including drug addiction. Here we focus on rodent studies over the past two decades that have demonstrated diverse roles of BDNF in models of cocaine addiction. First, we will provide an overview of studies showing that cocaine exposure alters (and generally increases) BDNF levels in reward-related regions including the ventral tegmental area, nucleus accumbens, prefrontal cortex, and amygdala. Then we will review evidence that BDNF contributes to behavioral changes in animal models of cocaine addiction, focusing on conditioned place preference, behavioral sensitization, maintenance and reinstatement of self-administration, and incubation of cocaine craving. Last, we will review the role of BDNF in synaptic plasticity, particularly as it relates to plasticity of AMPA receptor transmission after cocaine exposure. We conclude that BDNF regulates cocaine-induced behaviors in a highly complex manner that varies depending on the brain region (and even among different cell types within the same brain region), the nature of cocaine exposure, and the “addiction phase” examined (e.g., acquisition vs maintenance; early vs late withdrawal). These complexities make BDNF a daunting therapeutic target for treating cocaine addiction. However, recent clinical evidence suggests that the serum BDNF level may serve as a biomarker in cocaine addicts to predict future relapse, providing an alternative direction for exploring BDNF’s potential relevance to treating cocaine addiction. PMID:25449839

  15. Effect of voluntary exercise on BDNF/TrkB gene expression and alcohol intake.

    OpenAIRE

    Jonsson, Josefine

    2012-01-01

    Voluntary wheel running is rewarding and believed to activate the same brain reward system as in alcohol and drug addiction. Brain-derived neurotrophic factor (BDNF), a well-known growth factor widely expressed in the brain, is modulated by both voluntary exercise and alcohol consumption. The aim of this study was to evaluate how voluntary exercise affects the expression levels of BDNF and its receptor TrkB in brain regions involved in positive and negative reinforcement. Additionally we want...

  16. Fear extinction and BDNF: Translating animal models of PTSD to the clinic

    OpenAIRE

    Andero, Raül; Ressler, Kerry J.

    2012-01-01

    Brain-derived neurotrophic factor (BDNF) is the most studied neurotrophin involved in synaptic plasticity processes that are required for long-term learning and memory. Specifically, BDNF gene expression and activation of its high-affinity TrkB receptor are necessary in the amygdala, hippocampus and prefrontal cortex for the formation of emotional memories, including fear memories. Among the psychiatric disorders with altered fear processing there is Post-traumatic Stress Disorder (PTSD) whic...

  17. Exercise promotes the expression of brain derived neurotrophic factor (BDNF) through the action of the ketone body β-hydroxybutyrate

    Science.gov (United States)

    Sleiman, Sama F; Henry, Jeffrey; Al-Haddad, Rami; El Hayek, Lauretta; Abou Haidar, Edwina; Stringer, Thomas; Ulja, Devyani; Karuppagounder, Saravanan S; Holson, Edward B; Ratan, Rajiv R; Ninan, Ipe; Chao, Moses V

    2016-01-01

    Exercise induces beneficial responses in the brain, which is accompanied by an increase in BDNF, a trophic factor associated with cognitive improvement and the alleviation of depression and anxiety. However, the exact mechanisms whereby physical exercise produces an induction in brain Bdnf gene expression are not well understood. While pharmacological doses of HDAC inhibitors exert positive effects on Bdnf gene transcription, the inhibitors represent small molecules that do not occur in vivo. Here, we report that an endogenous molecule released after exercise is capable of inducing key promoters of the Mus musculus Bdnf gene. The metabolite β-hydroxybutyrate, which increases after prolonged exercise, induces the activities of Bdnf promoters, particularly promoter I, which is activity-dependent. We have discovered that the action of β-hydroxybutyrate is specifically upon HDAC2 and HDAC3, which act upon selective Bdnf promoters. Moreover, the effects upon hippocampal Bdnf expression were observed after direct ventricular application of β-hydroxybutyrate. Electrophysiological measurements indicate that β-hydroxybutyrate causes an increase in neurotransmitter release, which is dependent upon the TrkB receptor. These results reveal an endogenous mechanism to explain how physical exercise leads to the induction of BDNF. DOI: http://dx.doi.org/10.7554/eLife.15092.001 PMID:27253067

  18. BDNF-induced synaptic delivery of AMPAR subunits is differentially dependent on NMDA receptors and requires ERK.

    Science.gov (United States)

    Li, Wei; Keifer, Joyce

    2009-03-01

    Previous studies using an in vitro model of eyeblink classical conditioning in turtles suggest that increased numbers of synaptic AMPARs supports the acquisition and expression of conditioned responses (CRs). Brain-derived neurotrophic factor (BDNF) and its associated receptor tyrosine kinase, TrkB, is also required for acquisition of CRs. Bath application of BDNF alone induces synaptic delivery of GluR1- and GluR4-containing AMPARs that is blocked by coapplication of the receptor tyrosine kinase inhibitor K252a. The molecular mechanisms involved in BDNF-induced AMPAR trafficking remain largely unknown. The aim of this study was to determine whether BDNF-induced synaptic AMPAR incorporation utilizes similar cellular mechanisms as AMPAR trafficking that occurs during in vitro classical conditioning. Using pharmacological blockade and confocal imaging, the results show that synaptic delivery of GluR1 subunits during conditioning or BDNF application does not require activity of NMDARs but is mediated by extracellular signal-regulated kinase (ERK). In contrast, synaptic delivery of GluR4-containing AMPARs during both conditioning and BDNF application is NMDAR- as well as ERK-dependent. These findings indicate that BDNF application mimics AMPAR trafficking observed during conditioning by activation of some of the same intracellular signaling pathways and suggest that BDNF is a key signal transduction element in postsynaptic events that mediate conditioning.

  19. The impact of Bdnf gene deficiency to the memory impairment and brain pathology of APPswe/PS1dE9 mouse model of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Tomi Rantamäki

    Full Text Available Brain-derived neurotrophic factor (BDNF importantly regulates learning and memory and supports the survival of injured neurons. Reduced BDNF levels have been detected in the brains of Alzheimer's disease (AD patients but the exact role of BDNF in the pathophysiology of the disorder remains obscure. We have recently shown that reduced signaling of BDNF receptor TrkB aggravates memory impairment in APPswe/PS1dE9 (APdE9 mice, a model of AD. The present study examined the influence of Bdnf gene deficiency (heterozygous knockout on spatial learning, spontaneous exploratory activity and motor coordination/balance in middle-aged male and female APdE9 mice. We also studied brain BDNF protein levels in APdE9 mice in different ages showing progressive amyloid pathology. Both APdE9 and Bdnf mutations impaired spatial learning in males and showed a similar trend in females. Importantly, the effect was additive, so that double mutant mice performed the worst. However, APdE9 and Bdnf mutations influenced spontaneous locomotion in contrasting ways, such that locomotor hyperactivity observed in APdE9 mice was normalized by Bdnf deficiency. Obesity associated with Bdnf deficiency did not account for the reduced hyperactivity in double mutant mice. Bdnf deficiency did not alter amyloid plaque formation in APdE9 mice. Before plaque formation (3 months, BDNF protein levels where either reduced (female or unaltered (male in the APdE9 mouse cortex. Unexpectedly, this was followed by an age-dependent increase in mature BDNF protein. Bdnf mRNA and phospho-TrkB levels remained unaltered in the cortical tissue samples of middle-aged APdE9 mice. Immunohistological studies revealed increased BDNF immunoreactivity around amyloid plaques indicating that the plaques may sequester BDNF protein and prevent it from activating TrkB. If similar BDNF accumulation happens in human AD brains, it would suggest that functional BDNF levels in the AD brains are even lower than reported

  20. The impact of Bdnf gene deficiency to the memory impairment and brain pathology of APPswe/PS1dE9 mouse model of Alzheimer's disease.

    Science.gov (United States)

    Rantamäki, Tomi; Kemppainen, Susanna; Autio, Henri; Stavén, Saara; Koivisto, Hennariikka; Kojima, Masami; Antila, Hanna; Miettinen, Pasi O; Kärkkäinen, Elisa; Karpova, Nina; Vesa, Liisa; Lindemann, Lothar; Hoener, Marius C; Tanila, Heikki; Castrén, Eero

    2013-01-01

    Brain-derived neurotrophic factor (BDNF) importantly regulates learning and memory and supports the survival of injured neurons. Reduced BDNF levels have been detected in the brains of Alzheimer's disease (AD) patients but the exact role of BDNF in the pathophysiology of the disorder remains obscure. We have recently shown that reduced signaling of BDNF receptor TrkB aggravates memory impairment in APPswe/PS1dE9 (APdE9) mice, a model of AD. The present study examined the influence of Bdnf gene deficiency (heterozygous knockout) on spatial learning, spontaneous exploratory activity and motor coordination/balance in middle-aged male and female APdE9 mice. We also studied brain BDNF protein levels in APdE9 mice in different ages showing progressive amyloid pathology. Both APdE9 and Bdnf mutations impaired spatial learning in males and showed a similar trend in females. Importantly, the effect was additive, so that double mutant mice performed the worst. However, APdE9 and Bdnf mutations influenced spontaneous locomotion in contrasting ways, such that locomotor hyperactivity observed in APdE9 mice was normalized by Bdnf deficiency. Obesity associated with Bdnf deficiency did not account for the reduced hyperactivity in double mutant mice. Bdnf deficiency did not alter amyloid plaque formation in APdE9 mice. Before plaque formation (3 months), BDNF protein levels where either reduced (female) or unaltered (male) in the APdE9 mouse cortex. Unexpectedly, this was followed by an age-dependent increase in mature BDNF protein. Bdnf mRNA and phospho-TrkB levels remained unaltered in the cortical tissue samples of middle-aged APdE9 mice. Immunohistological studies revealed increased BDNF immunoreactivity around amyloid plaques indicating that the plaques may sequester BDNF protein and prevent it from activating TrkB. If similar BDNF accumulation happens in human AD brains, it would suggest that functional BDNF levels in the AD brains are even lower than reported, which could

  1. Antidepressant-like activity of red wine phenolic extracts in repeated corticosterone-induced depression mice via BDNF/TrkB/CREB signaling pathway

    Directory of Open Access Journals (Sweden)

    Jia Ying

    2016-01-01

    Full Text Available The aim of this study was to investigate the antidepressant-like effect of red wine phenolic extracts in mouse model exposed to exogenous corticosterone. The results showed that 3-week corticosterone injections caused depression-like behavior in mice, as indicated by the significant decrease in sucrose consumption and increase immobility time in the forced swim test. Red wine phenolic extracts treatment significantly reduced serum corticosterone levels. Moreover, it was found that red wine phenolic extract increased the brain-derived neurotrophic factor protein (BNDF and Tropomyosin-related kinase B (TrkB phosphorylation and cAMP-responsive element binding protein (CREB phosphorylation levels in the hippocampus and prefrontal cortex. However, K252a, an inhibitor of TrkB, completely abolished those antidepressant-like effects. These results suggested that the red wine phenolic extracts produce an antidepressant-like effect in corticosterone-treated mice, at least in part, which is possibly mediated by modulating hypothalamic-pituitary-adrenal (HPA axis, BDNF, TrkB and CREB phosphorylation levels in the brain region of mice.

  2. Restraint stress and repeated CRF receptor activation in the amygdala both increase amyloid β precursor protein (APP) and amyloid-β (Aβ) peptide but have divergent effects on BDNF and pre-synaptic proteins in the prefrontal cortex of rats

    OpenAIRE

    Ray, Balmiki; Gaskins, Denise L.; Sajdyk, Tammy J.; Spence, John P.; Fitz, Stephanie D.; Shekhar, Anantha; Lahiri, Debomoy K.

    2011-01-01

    Both environmental stress and anxiety may represent important risk factors for Alzheimer's disease (AD) pathogenesis. Previous studies demonstrate that restraint stress is associated with increased amyloid beta (Aβ) and decreased brain-derived neurotrophic factor (BDNF) levels in the brain. Aβ deposition, synaptic loss, and neurodegeneration define major hallmarks of AD, and BDNF is responsible for the maintenance of neurons. In contrast to restraint stress, repeated injections of sub-anxioge...

  3. Proteolytic Cleavage of ProBDNF into Mature BDNF in the Basolateral Amygdala Is Necessary for Defeat-Induced Social Avoidance

    Science.gov (United States)

    Dulka, Brooke N.; Ford, Ellen C.; Lee, Melissa A.; Donnell, Nathaniel J.; Goode, Travis D.; Prosser, Rebecca; Cooper, Matthew A.

    2016-01-01

    Brain-derived neurotrophic factor (BDNF) is essential for memory processes. The present study tested whether proteolytic cleavage of proBDNF into mature BDNF (mBDNF) within the basolateral amygdala (BLA) regulates the consolidation of defeat-related memories. We found that acute social defeat increases the expression of mBDNF, but not proBDNF, in…

  4. Regulation of brain-derived neurotrophic factor (BDNF) in the chronic unpredictable stress rat model and the effects of chronic antidepressant treatment

    DEFF Research Database (Denmark)

    Larsen, Marianne H; Mikkelsen, Jens D; Hay-Schmidt, Anders;

    2010-01-01

    swim test in stressed rats. Present evidence suggests a role for brain-derived neurotrophic factor (BDNF) in depression. BDNF mRNA levels in the ventral and dorsal hippocampus were assessed by in situ hybridization. Exposure to CUS was not correlated with a decrease but rather with an increase in BDNF...... mRNA expression in both the dentate gyrus of the dorsal hippocampus and the CA3 region of the ventral hippocampus indicating that there is no simple link between depression-like behaviors per se and brain BDNF levels in rats. However, a significant increase in BDNF mRNA levels in the dentate gyrus...... of the dorsal hippocampus correlated with chronic antidepressant treatment emphasizing a role for BDNF in the mechanisms underlying antidepressant activity....

  5. Aerobic exercise improves hippocampal function and increases BDNF in the serum of young adult males.

    Science.gov (United States)

    Griffin, Éadaoin W; Mullally, Sinéad; Foley, Carole; Warmington, Stuart A; O'Mara, Shane M; Kelly, Aine M

    2011-10-24

    Physical activity has been reported to improve cognitive function in humans and rodents, possibly via a brain-derived neurotrophic factor (BDNF)-regulated mechanism. In this study of human subjects, we have assessed the effects of acute and chronic exercise on performance of a face-name matching task, which recruits the hippocampus and associated structures of the medial temporal lobe, and the Stroop word-colour task, which does not, and have assessed circulating concentrations of BDNF and IGF-1 in parallel. The results show that a short period of high-intensity cycling results in enhancements in performance of the face-name matching, but not the Stroop, task. These changes in cognitive function were paralleled by increased concentration of BDNF, but not IGF-1, in the serum of exercising subjects. 3 weeks of cycling training had no effect on cardiovascular fitness, as assessed by VO2 scores, cognitive function, or serum BDNF concentration. Increases in fitness, cognitive function and serum BDNF response to acute exercise were observed following 5 weeks of aerobic training. These data indicate that both acute and chronic exercise improve medial temporal lobe function concomitant with increased concentrations of BDNF in the serum, suggesting a possible functional role for this neurotrophic factor in exercise-induced cognitive enhancement in humans. PMID:21722657

  6. Brain-derived neurotrophic factor (BDNF) and its precursor (proBDNF) in genetically defined fear-induced aggression.

    Science.gov (United States)

    Ilchibaeva, Tatiana V; Kondaurova, Elena M; Tsybko, Anton S; Kozhemyakina, Rimma V; Popova, Nina K; Naumenko, Vladimir S

    2015-09-01

    The brain-derived neurotrophic factor (BDNF), its precursor (proBDNF) and BDNF mRNA levels were studied in the brain of wild rats selectively bred for more than 70 generations for either high level or for the lack of affective aggressiveness towards man. Significant increase of BDNF mRNA level in the frontal cortex and increase of BDNF level in the hippocampus of aggressive rats was revealed. In the midbrain and hippocampus of aggressive rats proBDNF level was increased, whereas BDNF/proBDNF ratio was reduced suggesting the prevalence and increased influence of proBDNF in highly aggressive rats. In the frontal cortex, proBDNF level in aggressive rats was decreased. Thus, considerable structure-specific differences in BDNF and proBDNF levels as well as in BDNF gene expression between highly aggressive and nonaggressive rats were shown. The data suggested the implication of BDNF and its precursor proBDNF in the mechanism of aggressiveness and in the creation of either aggressive or nonaggressive phenotype.

  7. Cosmological perturbations in mimetic matter model

    CERN Document Server

    Matsumoto, Jiro; Sushkov, Sergey V

    2015-01-01

    We investigate the cosmological evolution of mimetic matter model with arbitrary scalar potential. The cosmological reconstruction is explicitly done for different choices of potential. The cases that mimetic matter model shows the evolution as Cold Dark Matter(CDM), wCDM model, dark matter and dark energy with dynamical $Om(z)$ or phantom dark energy with phantom-non-phantom crossing are presented in detail. The cosmological perturbations for such evolution are studied in mimetic matter model. For instance, the evolution behavior of the matter density contrast which is different from usual one, i.e. $\\ddot \\delta + 2 H \\dot \\delta - \\kappa ^2 \\rho \\delta /2 = 0$ is investigated. The possibility of peculiar evolution of $\\delta$ in the model under consideration is shown. Special attention is paid to the behavior of matter density contrast near to future singularity where decay of perturbations may occur much earlier the singularity.

  8. A selective histone deacetylase-6 inhibitor improves BDNF trafficking in hippocampal neurons from Mecp2 knockout mice:implications for Rett syndrome

    Directory of Open Access Journals (Sweden)

    Xin eXu

    2014-03-01

    Full Text Available Rett syndrome (RTT is a neurodevelopmental disorder caused by loss-of-function mutations in the transcriptional modulator methyl-CpG-binding protein 2 (MECP2. One of the most prominent gene targets of MeCP2 is brain-derived neurotrophic factor (Bdnf, a potent modulator of activity-dependent synaptic development, function and plasticity. Dysfunctional BDNF signaling has been demonstrated in several pathophysiological mechanisms of RTT disease progression. To evaluate whether the dynamics of BDNF trafficking is affected by Mecp2 deletion, we analyzed movements of BDNF tagged with yellow fluorescent protein (YFP in cultured hippocampal neurons by time-lapse fluorescence imaging. We found that both anterograde and retrograde vesicular trafficking of BDNF-YFP are significantly impaired in Mecp2 knockout hippocampal neurons. Selective inhibitors of histone deacetylase 6 (HDAC6 show neuroprotective effects in neurodegenerative diseases and stimulate microtubule-dependent vesicular trafficking of BDNF-containing dense core vesicles. Here, we show that the selective HDAC6 inhibitor Tubastatin-A increased the velocity of BDNF-YFP vesicles in Mecp2 knockout neurons in both directions by increasing αtubulin acetylation. Tubastatin-A also restored activity-dependent BDNF release from Mecp2 knockout neurons to levels comparable to those shown by wildtype neurons. These findings demonstrate that a selective HDAC6 inhibitor is a potential pharmacological strategy to reverse cellular and synaptic impairments in RTT resulting from impaired BDNF signaling.

  9. Mimetic desire and scapegoat mechanism in sport

    Directory of Open Access Journals (Sweden)

    Jernej Pisk

    2012-12-01

    Full Text Available BACKGROUND: The most fundamental question about sport is what is sport, what is its origin and its essence? Because sport is connected with the human being (there is no sport without human beings different anthropological visions of human being result in different understandings of sport. OBJECTIVE: The objective of this paper is to present and explain an anthropological vision of the human being and society as was developed by René Girard. In his view mimetic desire and the scapegoat mechanism have a central role in any culture, religion or other secular institutions. The explanatory power of his theory is presented when it is applied to the world of sport. METHODS: Our methodology is philosophical, involving conceptual analysis and the application of the outcomes to sport. RESULTS: In the paper we show that mimetic desire can be recognized as one of the important origins of recreational and competitive sports. When people recognize what other people are able to do or accomplish in sport this invokes the mimetic desire as a result of which motivation for sport and competiveness can arise. But mimetic rivalry leads to an unstable situation. Therefore a second element is needed: Scapegoating in sport is presented as a mean to preserve the good reputation of sport, to keep peace in sport as well as in society as a whole. Finally, the attempt to overcome mimetic desire and scapegoating in sport is presented and the question if this is worth trying at all is opened. CONCLUSIONS: The theories of mimetic desire and scapegoat mechanism have great explanatory power when they are applied to the field of sport. They could reveal us some hidden motives and forces which drive athletes and sport as a whole. Moreover, they exceed the world of sport and reveal the influence of sport on the whole of society.

  10. Differential Expression and Regulation of Brain-Derived Neurotrophic Factor (BDNF) mRNA Isoforms in Brain Cells from Mecp2(308/y) Mouse Model.

    Science.gov (United States)

    Rousseaud, Audrey; Delépine, Chloé; Nectoux, Juliette; Billuart, Pierre; Bienvenu, Thierry

    2015-08-01

    Rett syndrome (RTT) is a severe neurodevelopmental disease caused by mutations in methyl-CpG-binding protein 2 (MECP2), which encodes a transcriptional modulator of many genes including BDNF. BDNF comprises nine distinct promoter regions, each triggering the expression of a specific transcript. The role of this diversity of transcripts remains unknown. MeCP2 being highly expressed in neurons, RTT was initially considered as a neuronal disease. However, recent studies have shown that MeCP2 was also expressed in astrocytes. Though several studies explored Bdnf IV expression in Mecp2-deficient mice, the differential expression of Bdnf isoforms in Mecp2-deficient neurons and astrocytes was never studied. By using TaqMan technology and a mouse model expressing a truncated Mecp2 (Mecp2(308/y)), we firstly showed in neurons that Bdnf transcripts containing exon I, IIb, IIc, IV, and VI are prominently expressed, whereas in astrocytes, Bdnf transcript containing exon VI is preferentially expressed, suggesting a specific regulation of Bdnf expression at the cellular level. Secondly, we confirmed the repressive role of Mecp2 only on the expression of Bdnf VI in neurons. Our data suggested that the truncated Mecp2 protein maintains its function on Bdnf expression regulation in neurons and in astrocytes. Interestingly, we observed that Bdnf transcripts (I and IXA), regulated by neural activity induced by bicuculline in Mecp2(308/y) neurons, were not affected by histone deacetylase inhibition. In contrast, Bdnf transcripts (IIb, IIc, and VI), regulated by histone deacetylation, were not affected by bicuculline treatment in wild-type and Mecp2(308/y) neurons. All these results reflect the complexity of regulation of Bdnf gene.

  11. RNA interference-mediated knockdown of brain-derived neurotrophic factor (BDNF) promotes cell cycle arrest and apoptosis in B-cell lymphoma cells.

    Science.gov (United States)

    Xia, D; Li, W; Zhang, L; Qian, H; Yao, S; Qi, X

    2014-01-01

    Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin superfamily that has been reported to be involved in a number of neurological and psychological situations. Recently, high expression level of BDNF is observed in diverse human malignancies, delineating a role of BDNF in tumorigenesis. Nevertheless, its effect on B-cell lymphoma remains unclear. In this study, RNA interference technology mediated by short hairpin RNA (shRNA) was performed to inhibit endogenous BDNF expression in B-cell lymphoma cells. Results showed that knockdown of BDNF reduced cell growth and proliferation of Raji and Ramos cells. Furthermore, down-regulation of BDNF induced a cell cycle arrest at G0/G1 phase in Raji cells, and consequently led to cell apoptosis in vitro. Meanwhile, down-regulation of Bcl-2 and up-regulation of Bax, activated caspase-3 and caspase-9 and cleaved poly (ADP-ribose) polymerase (PARP) were observed in Raji cells when endogenous BDNF was inhibited. Besides, we also found that suppression of BDNF in Raji cells increased their sensitivity to chemotherapeutic drug, 5-Fluorouracil (5-FU). Our research provides a promising therapeutic strategy for human B-cell lymphoma by targeting BDNF.

  12. Mimetic dark matter, ghost instability and a mimetic tensor-vector-scalar gravity

    OpenAIRE

    Chaichian, Masud; Klusoň, Josef; Oksanen, Markku; Tureanu, Anca

    2014-01-01

    Recently modified gravitational theories which mimic the behaviour of dark matter, the so-called "Mimetic Dark Matter", have been proposed. We study the consistency of such theories with respect to the absence of ghost instability and propose a new tensor-vector-scalar theory of gravity, which is a generalization of the previous models of mimetic dark matter with additional desirable features. The original model proposed by Chamseddine and Mukhanov [JHEP 1311 (2013) 135, arXiv:1308.5410] is c...

  13. Antibody mimetics: promising complementary agents to animal-sourced antibodies.

    Science.gov (United States)

    Baloch, Abdul Rasheed; Baloch, Abdul Wahid; Sutton, Brian J; Zhang, Xiaoying

    2016-01-01

    Despite their wide use as therapeutic, diagnostic and detection agents, the limitations of polyclonal and monoclonal antibodies have inspired scientists to design the next generation biomedical agents, so-called antibody mimetics that offer many advantages over conventional antibodies. Antibody mimetics can be constructed by protein-directed evolution or fusion of complementarity-determining regions through intervening framework regions. Substantial progress in exploiting human, butterfly (Pieris brassicae) and bacterial systems to design and select mimetics using display technologies has been made in the past 10 years, and one of these mimetics [Kalbitor® (Dyax)] has made its way to market. Many challenges lie ahead to develop mimetics for various biomedical applications, especially those for which conventional antibodies are ineffective, and this review describes the current characteristics, construction and applications of antibody mimetics compared to animal-sourced antibodies. The possible limitations of mimetics and future perspectives are also discussed. PMID:25264572

  14. BDNF over-expression increases olfactory bulb granule cell dendritic spine density in vivo.

    Science.gov (United States)

    McDole, B; Isgor, C; Pare, C; Guthrie, K

    2015-09-24

    Olfactory bulb granule cells (GCs) are axon-less, inhibitory interneurons that regulate the activity of the excitatory output neurons, the mitral and tufted cells, through reciprocal dendrodendritic synapses located on GC spines. These contacts are established in the distal apical dendritic compartment, while GC basal dendrites and more proximal apical segments bear spines that receive glutamatergic inputs from the olfactory cortices. This synaptic connectivity is vital to olfactory circuit function and is remodeled during development, and in response to changes in sensory activity and lifelong GC neurogenesis. Manipulations that alter levels of the neurotrophin brain-derived neurotrophic factor (BDNF) in vivo have significant effects on dendritic spine morphology, maintenance and activity-dependent plasticity for a variety of CNS neurons, yet little is known regarding BDNF effects on bulb GC spine maturation or maintenance. Here we show that, in vivo, sustained bulbar over-expression of BDNF in transgenic mice produces a marked increase in GC spine density that includes an increase in mature spines on their apical dendrites. Morphometric analysis demonstrated that changes in spine density were most notable in the distal and proximal apical domains, indicating that multiple excitatory inputs are potentially modified by BDNF. Our results indicate that increased levels of endogenous BDNF can promote the maturation and/or maintenance of dendritic spines on GCs, suggesting a role for this factor in modulating GC functional connectivity within adult olfactory circuitry. PMID:26211445

  15. A possible link between BDNF and mTOR in control of food intake

    Directory of Open Access Journals (Sweden)

    Nobuyuki eTakei

    2014-09-01

    Full Text Available Food intake is intricately regulated by glucose, amino acids, hormones, neuropeptides, and trophic factors through a neural circuit in the hypothalamus. Brain-derived neurotrophic factor (BDNF, the most prominent neurotrophic factor in the brain, regulates differentiation, maturation, and synaptic plasticity throughout life. Among its many roles, BDNF exerts an anorexigenic function in the brain. However, the intracellular signaling induced by BDNF to control food intake is not fully understood. One candidate for the molecule involved in transducing the anorexigenic activity of BDNF is the mammalian target of rapamycin (mTOR. mTOR senses extracellular amino acids, glucose, growth factors, and neurotransmitters, and regulates anabolic reactions response to these signals. Activated mTOR increases protein and lipid synthesis and inhibits protein degradation. In the hypothalamus, mTOR activation is thought to reduce food intake. Here we summarize recent findings regarding BDNF- and mTOR-mediated feeding control, and propose a link between these molecules in eating behavior.

  16. DNA Methylation of BDNF Gene in Schizophrenia

    Science.gov (United States)

    Çöpoğlu, Ümit Sertan; İğci, Mehri; Bozgeyik, Esra; Kokaçya, M. Hanifi; İğci, Yusuf Ziya; Dokuyucu, Recep; Arı, Mustafa; Savaş, Haluk A.

    2016-01-01

    Background Although genetic factors are risk factors for schizophrenia, some environmental factors are thought to be required for the manifestation of disease. Epigenetic mechanisms regulate gene functions without causing a change in the nucleotide sequence of DNA. Brain-derived neurotrophic factor (BDNF) is a neurotrophin that regulates synaptic transmission and plasticity. It has been suggested that BDNF may play a role in the pathophysiology of schizophrenia. It is established that methylation status of the BDNF gene is associated with fear learning, memory, and stressful social interactions. In this study, we aimed to investigate the DNA methylation status of BDNF gene in patients with schizophrenia. Material/Methods The study included 49 patients (33 male and 16 female) with schizophrenia and 65 unrelated healthy controls (46 male and 19 female). Determination of methylation pattern of CpG islands was based on the principle that bisulfite treatment of DNA results in conversion of unmethylated cytosine residues into uracil, whereas methylated cytosine residues remain unmodified. Methylation-specific PCR was performed with primers specific for either methylated or unmethylated DNA. Results There was no significant difference in methylated or un-methylated status for BDNF promoters between schizophrenia patients and controls. The mean duration of illness was significantly lower in the hemi-methylated group compared to the non-methylated group for BDNF gene CpG island-1 in schizophrenia patients. Conclusions Although there were no differences in BDNF gene methylation status between schizophrenia patients and healthy controls, there was an association between duration of illness and DNA methylation. PMID:26851233

  17. Fluorescence Spectra and Enzymatic Property of Hemoglobin as Mimetic Peroxidase

    Institute of Scientific and Technical Information of China (English)

    LiDe-jia; LiHai-cheng; ZouGuo-lin

    2003-01-01

    Intrinsic fluorescence emission maxima of hemo-lobin(Hb) was investigated in relation to peroxidase property of Hb. The peroxidase activity of Hb was based on its catalytic activity for oxidation of o-phenylenediamine by hydrogen peroxide. Hb was treated in the condition (temperature,ethanol and salt) that tetramer-dimer equilibrium of Hb is shifted to the dimer state and its fluorescence spectrum was measured. When Hb treated in temperature (60-70 ℃), ethanol concentration (60%-70%) and NaCl concentration (2. 5-3.0 mol/L), the fluorescence emission maxima of Hb shifted towards red wavelength and its activity decreased quickly.Experimental results revealed that the activity and stability of Hb as mimetic peroxidase was closely relative to the hydrophobic environment of active center of Hb, and when Hb (FeⅡ) converted into met Hb (FeⅢ ), its activity was 1. 6 times as much as that of Hb.

  18. Fluorescence Spectra and Enzymatic Property of Hemoglobin as Mimetic Peroxidase

    Institute of Scientific and Technical Information of China (English)

    Li De-jia; Li Hai-cheng; Zou Guo-lin

    2003-01-01

    Intrinsic fluorescence emission maxima of hemoglobin(Hb) was investigated in relation to peroxidase property of Hb. The peroxidase activity of Hb was based on its catalytic activity for oxidation of o-phenylenediamine by hydrogen peroxide. Hb was treated in the condition (temperature,ethanol and salt) that tetramer-dimer equilibrium of Hb is shifted to the dimer state and its fluorescence spectrum was measured. When Hb treated in temperature (60-70 ℃ ), ethanol concentration (60 %-70 % ) and NaCl concentration (2.5-3.0 mol/L), the fluorescence emission maxima of Hb shifted towards red wavelength and its activity decreased quickly.Experimental results revealed that the activity and stability of Hb as mimetic peroxidase was closely relative to the hydrophobic environment of active center of Hb, and when Hb (FeⅡ) converted into met Hb (FeⅢ ), its activity was 1. 6times as much as that of Hb.

  19. BDNF interacts with endocannabinoids to regulate cocaine-induced synaptic plasticity in mouse midbrain dopamine neurons.

    Science.gov (United States)

    Zhong, Peng; Liu, Yong; Hu, Ying; Wang, Tong; Zhao, Yong-ping; Liu, Qing-song

    2015-03-11

    Brain-derived neurotrophic factor (BDNF) and endocannabinoids (eCBs) have been individually implicated in behavioral effects of cocaine. The present study examined how BDNF-eCB interaction regulates cocaine-induced synaptic plasticity in the ventral tegmental area and behavioral effects. We report that BDNF and selective tyrosine kinase receptor B (TrkB) agonist 7,8-dihydroxyflavone (DHF) activated the TrkB receptor to facilitate two forms of eCB-mediated synaptic depression, depolarization-induced suppression of inhibition (DSI), and long-term depression (I-LTD) of IPSCs in ventral tegmental area dopamine neurons in mouse midbrain slices. The facilitation appears to be mediated by an increase in eCB production via phospholipase Cγ pathway, but not by an increase in CB1 receptor responsiveness or a decrease in eCB hydrolysis. Using Cre-loxP technology to specifically delete BDNF in dopamine neurons, we showed that eCB-mediated I-LTD, cocaine-induced reduction of GABAergic inhibition, and potentiation of glutamatergic excitation remained intact in wild-type control mice, but were impaired in BDNF conditional knock-out mice. We also showed that cocaine-induced conditioned place preference was attenuated in BDNF conditional knock-out mice, in vivo pretreatments with DHF before place conditioning restored cocaine conditioned place preference in these mice, and the behavioral effect of DHF was blocked by a CB₁ receptor antagonist. Together, these results suggest that BDNF in dopamine neurons regulates eCB responses, cocaine-induced synaptic plasticity, and associative learning. PMID:25762688

  20. Regulated release of BDNF by cortical oligodendrocytes is mediated through metabotropic glutamate receptors and the PLC pathway

    Directory of Open Access Journals (Sweden)

    Issa P Bagayogo

    2009-04-01

    Full Text Available A number of studies suggest that OLGs (oligodendrocytes), the myelinating cells of the central nervous system, are also a source of trophic molecules, such as neurotrophins that may influence survival of proximate neurons. What is less clear is how the release of these molecules may be regulated. The present study investigated the effects of BDNF (brain-derived neurotrophic factor) derived from cortical OLGs on proximate neurons, as well as regulatory mechanisms mediating BDNF release. Initial work determined that BDNF derived from cortical OLGs increased the numbers of VGLUT1 (vesicular glutamate transporter 1)-positive glutamatergic cortical neurons. Furthermore, glutamate acting through metabotropic, and not AMPA/kainate or NMDA (N-methyl-d-aspartate), receptors increased BDNF release. The PLC (phospholipase C) pathway is a key mediator of metabotropic actions to release BDNF in astrocytes and neurons. Treatment of OLGs with the PLC activator m-3M3FBS [N-(3-trifluoromethylphenyl)-2,4,6-trimethylbenzenesulfonamide] induced robust release of BDNF. Moreover, release elicited by the metabotropic receptor agonist ACPD [trans-(1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid] was inhibited by the PLC antagonist U73122, the IP3 (inositol triphosphate 3) receptor inhibitor 2-APB (2-aminoethoxydiphenylborane) and the intracellular calcium chelator BAPTA/AM [1,2-bis-(o-aminophenoxy)ethane-N,N,N′,N′-tetra-acetic acid tetrakis(acetoxymethyl ester)]. Taken together, these results suggest that OLG lineage cells release BDNF, a molecule trophic for proximate neurons. BDNF release is regulated by glutamate acting through mGluRs (metabotropic glutamate receptors) and the PLC pathway. Thus glutamate and BDNF may be molecules that support neuron–OLG interactions in the cortex.

  1. Prolonged abstinence from developmental cocaine exposure dysregulates BDNF and its signaling network in the medial prefrontal cortex of adult rats.

    Science.gov (United States)

    Giannotti, Giuseppe; Caffino, Lucia; Calabrese, Francesca; Racagni, Giorgio; Riva, Marco A; Fumagalli, Fabio

    2014-04-01

    Although evidence exists that chronic cocaine exposure during adulthood is associated with changes in BDNF expression, whether and how cocaine exposure during adolescence modulates BDNF is still unknown. To address this issue, we exposed rats to repeated cocaine injections from post-natal day (PD) 28 to PD 42, a period that roughly approximates adolescence in humans, and we carried out a detailed analysis of the BDNF system in the medial prefrontal cortex (mPFC) of rats sacrificed 3 d (PD 45) and 48 d (PD 90) after the last cocaine treatment. We found that developmental exposure to cocaine altered transcriptional and translational mechanisms governing neurotrophin expression. Total BDNF mRNA levels, in fact, were enhanced in the mPFC of PD 90 rats exposed to cocaine in adolescence, an effect sustained by changes in BDNF exon IV through the transcription factors CaRF and NF-kB. While a profound reduction of specific BDNF-related miRNAs (let7d, miR124 and miR132) may contribute to explaining the increased proBDNF levels, the up-regulation of the extracellular proteases tPA is indicative of increased processing leading to higher levels of released mBDNF. These changes were associated with increased activation of the trkB-Akt pathway resulting in enhanced pmTOR and pS6 kinase, which ultimately produced an up-regulation of Arc and a consequent reduction of GluA1 expression in the mPFC of PD 90 cocaine-treated rats. These findings demonstrate that developmental exposure to cocaine dynamically dysregulates BDNF and its signaling network in the mPFC of adult rats, providing novel mechanisms that may contribute to cocaine-induced changes in synaptic plasticity. PMID:24345425

  2. Cysteamine-related agents could be potential antidepressants through increasing central BDNF levels.

    Science.gov (United States)

    Tsai, Shih-Jen

    2006-01-01

    Major depressive disorder (MDD) is a common mental disease, but with an unknown etiology. Antidepressants are the main biological treatment for MDD. However, current antidepressive agents have a slow onset of effect and a substantial proportion of MDD patients do not clinically improve, despite maximal medication. Thus, the exploration for new antidepressants with novel strategies may help to develop faster and more effective antidepressant agents. Studies in the recent decades have demonstrated that antidepressants increase central brain-derived neurotrophic factor (BDNF) levels and activating the BDNF-signaling pathway may play an important role in their therapeutic mechanism. Cysteamine is a natural product of cells and constitutes the terminal region of the CoA molecule. Recent work has found that cysteamine and a related agent, cystamine, have neuroprotective effects in Huntington's disease (HD) mice, through enhancing central BDNF levels. Furthermore, cystamine or cysteamine injection could increase serum BDNF levels in wild-type mice as well as HD mice. Since activation of the BDNF-dependent pathway plays an important role in the mechanism of antidepressant therapeutic action, cystamine or its derivatives could have potential antidepressant therapeutic effects. Among these agents, pantethine may be one of the most promising agents. It is a naturally occurring compound which can be administered orally with negligible side effects, and is metabolized to cysteamine. Further evaluation of the therapeutic and toxic effects of these cysteamine-related antidepressant agents in MDD animal models is needed before any clinical application. PMID:16797865

  3. BDNF Genotype Modulates Resting Functional Connectivity in Children

    OpenAIRE

    Thomason, Moriah E.; Daniel J Yoo; Glover, Gary H.; Gotlib, Ian H.

    2009-01-01

    A specific polymorphism of the brain-derived neurotrophic factor (BDNF) gene is associated with alterations in brain anatomy and memory; its relevance to the functional connectivity of brain networks, however, is unclear. Given that altered hippocampal function and structure has been found in adults who carry the methionine (met) allele of the BDNF gene and the molecular studies elucidating the role of BDNF in neurogenesis and synapse formation, we examined the association between BDNF gene v...

  4. BDNF genotype modulates resting functional connectivity in children

    OpenAIRE

    Daniel J Yoo; Glover, Gary H.

    2009-01-01

    A specific polymorphism of the brain-derived neurotrophic factor (BDNF) gene is associated with alterations in brain anatomy and memory; its relevance to the functional connectivity of brain networks, however, is unclear. Given that altered hippocampal function and structure has been found in adults who carry the methionine (met) allele of the BDNF gene and the molecular studies elucidating the role of BDNF in neurogenesis and synapse formation, we examined in the association between BDNF gen...

  5. Apoptosis signal-regulating kinase 1 is involved in brain-derived neurotrophic factor (BDNF)-enhanced cell motility and matrix metalloproteinase 1 expression in human chondrosarcoma cells.

    Science.gov (United States)

    Lin, Chih-Yang; Chang, Sunny Li-Yun; Fong, Yi-Chin; Hsu, Chin-Jung; Tang, Chih-Hsin

    2013-07-25

    Chondrosarcoma is the primary malignancy of bone that is characterized by a potent capacity to invade locally and cause distant metastasis, and is therefore associated with poor prognoses. Chondrosarcoma further shows a predilection for metastasis to the lungs. The brain-derived neurotrophic factor (BDNF) is a small molecule in the neurotrophin family of growth factors that is associated with the disease status and outcome of cancers. However, the effect of BDNF on cell motility in human chondrosarcoma cells is mostly unknown. Here, we found that human chondrosarcoma cell lines had significantly higher cell motility and BDNF expression compared to normal chondrocytes. We also found that BDNF increased cell motility and expression of matrix metalloproteinase-1 (MMP-1) in human chondrosarcoma cells. BDNF-mediated cell motility and MMP-1 up-regulation were attenuated by Trk inhibitor (K252a), ASK1 inhibitor (thioredoxin), JNK inhibitor (SP600125), and p38 inhibitor (SB203580). Furthermore, BDNF also promoted Sp1 activation. Our results indicate that BDNF enhances the migration and invasion activity of chondrosarcoma cells by increasing MMP-1 expression through a signal transduction pathway that involves the TrkB receptor, ASK1, JNK/p38, and Sp1. BDNF thus represents a promising new target for treating chondrosarcoma metastasis.

  6. Comparison of the Adulthood Chronic Stress Effect on Hippocampal BDNF Signaling in Male and Female Rats.

    Science.gov (United States)

    Niknazar, Somayeh; Nahavandi, Arezo; Peyvandi, Ali Asghar; Peyvandi, Hassan; Akhtari, Amin Shams; Karimi, Mohsen

    2016-08-01

    Studies show that gender plays an important role in stress-related disorders, and women are more vulnerable to its effect. The present study was undertaken to investigate differences in the change in expression of brain-derived neurotrophic factor (BDNF), and its tyrosine intracellular kinase-activating receptor (TrkB) genes in the male and female rats' hippocampus (HPC) under chronic mild repeated stress (CMRS) conditions. In this experiment, male and female Wistar rats were randomly divided into two groups: the CMRS and the control group. To induce stress, a repeated forced swimming paradigm was employed daily for adult male and female rats for 21 days. At the end of the stress phase, elevated plus maze (EPM) was used for measuring the stress behavioral effects. Serum corticosterone level was measured by ELISA. BDNF and TrkB gene methylation and protein expression in the HPC were detected using real-time PCR and Western blotting. Chronic stress in the adolescence had more effects on anxiety-like behavior and serum corticosterone concentration in female rats than males. Furthermore, stressed female rats had higher methylation levels and following reduced protein expression of BDNF but not TrkB compared to stressed male rats. These findings suggest that in exposure to a stressor, sex differences in BDNF methylation may be root cause of decreased BDNF levels in females and may underlie susceptibility to pathology development. PMID:26189832

  7. The Impact of Bdnf Gene Deficiency to the Memory Impairment and Brain Pathology of APPswe/PS1dE9 Mouse Model of Alzheimer’s Disease

    Science.gov (United States)

    Rantamäki, Tomi; Kemppainen, Susanna; Autio, Henri; Stavén, Saara; Koivisto, Hennariikka; Kojima, Masami; Antila, Hanna; Miettinen, Pasi O.; Kärkkäinen, Elisa; Karpova, Nina; Vesa, Liisa; Lindemann, Lothar; Hoener, Marius C.; Tanila, Heikki; Castrén, Eero

    2013-01-01

    Brain-derived neurotrophic factor (BDNF) importantly regulates learning and memory and supports the survival of injured neurons. Reduced BDNF levels have been detected in the brains of Alzheimer’s disease (AD) patients but the exact role of BDNF in the pathophysiology of the disorder remains obscure. We have recently shown that reduced signaling of BDNF receptor TrkB aggravates memory impairment in APPswe/PS1dE9 (APdE9) mice, a model of AD. The present study examined the influence of Bdnf gene deficiency (heterozygous knockout) on spatial learning, spontaneous exploratory activity and motor coordination/balance in middle-aged male and female APdE9 mice. We also studied brain BDNF protein levels in APdE9 mice in different ages showing progressive amyloid pathology. Both APdE9 and Bdnf mutations impaired spatial learning in males and showed a similar trend in females. Importantly, the effect was additive, so that double mutant mice performed the worst. However, APdE9 and Bdnf mutations influenced spontaneous locomotion in contrasting ways, such that locomotor hyperactivity observed in APdE9 mice was normalized by Bdnf deficiency. Obesity associated with Bdnf deficiency did not account for the reduced hyperactivity in double mutant mice. Bdnf deficiency did not alter amyloid plaque formation in APdE9 mice. Before plaque formation (3 months), BDNF protein levels where either reduced (female) or unaltered (male) in the APdE9 mouse cortex. Unexpectedly, this was followed by an age-dependent increase in mature BDNF protein. Bdnf mRNA and phospho-TrkB levels remained unaltered in the cortical tissue samples of middle-aged APdE9 mice. Immunohistological studies revealed increased BDNF immunoreactivity around amyloid plaques indicating that the plaques may sequester BDNF protein and prevent it from activating TrkB. If similar BDNF accumulation happens in human AD brains, it would suggest that functional BDNF levels in the AD brains are even lower than reported, which could

  8. Oestrogene mimetic isoflavones’ pharmacokinetics and pharmacodynamics

    Directory of Open Access Journals (Sweden)

    Anca Dragomirescu,

    2008-12-01

    Full Text Available Genisteine is the most abundant and the most studied estrogen-mimetic izoflavone. It's chemical formula is 4',5,7 – trihidroxyisoflavone. It has also estrogen-modulated properties by its binding ability to the beta type estrogen receptor. Genisteine presents the following farmacodinamic effects: antiaterogen effect, prevention of estrogen-dependent cancers, especially breast cancer, prevention of skin aging body, osteoprogen effect, prevention of osteoporosis at the menopauses women. Despite all these real benefits, there are also many adverse effects, registered both in humans and animals. Thus, the sheep feeding with some Fabaceae species, containing estrogen-mimetic isoflavones were stopped their reproductive function(isoflavones acted as an oral contraceptive. In humans, phytoestroges influence is still under evaluation, being suspected effects such as cerebral involution - via abusive apoptosis - or disturbance in hormonal status, in male children. All these are added to already known allergies, caused by soy proteins.

  9. A note on a mimetic scalar-tensor cosmological model

    Energy Technology Data Exchange (ETDEWEB)

    Rabochaya, Yevgeniya; Zerbini, Sergio [Universita di Trento, Dipartimento di Fisica, Povo, Trento (Italy); TIFPA-INFN, Povo, Trento (Italy)

    2016-02-15

    A specific Hordenski scalar-gravity mimetic model is investigated within a FLWR space-time. The mimetic scalar field is implemented via a Lagrangian multiplier, and it is shown that the model has equations of motion formally similar to the original simpler mimetic matter model of Chamseddine-Mukhanov-Vikman. Several exact solutions describing inflation, bounces, and future-time singularities are presented and discussed. (orig.)

  10. Effect of Brain-derived Neurotrophic Factor (BDNF in Organotypic Retinal Cultures

    Directory of Open Access Journals (Sweden)

    N.A. Gavrilova

    2009-02-01

    Full Text Available ABSTRACT Purpose To study the influence of recombinant brain-derived neurotrophic factor (BDNF on organotypic retinal cultures. Material and methods Experiments were performed in human and rat retinal explants cultured in culture dishes, flasks and flasks for roller cultivation. BDNF was added at the concentration of 100 ng⁄ml. Cultures were tested for viability and stained immunohistochemically for neuronal markers. Culture conditions and results of cultivation were controlled using phase contrast and fluorescent microscopes. Conclusions Results of the study showed that cultivation of organotypic cultures of the human and rat retina in the presence of BDNF at the concentration of 100 ng⁄ml increases viability of retinal cells. Active cell migration and outgrowth of β-III-tubulin-positive axon-like processes of neuronal origin outside the borders of explants were observed.

  11. Cosmological perturbations in a mimetic matter model

    Science.gov (United States)

    Matsumoto, Jiro; Odintsov, Sergei D.; Sushkov, Sergey V.

    2015-03-01

    We investigate the cosmological evolution of a mimetic matter model with arbitrary scalar potential. The cosmological reconstruction—which is the method for constructing a model for an arbitrary evolution of the scale factor—is explicitly performed for different choices of potential. The cases where the mimetic matter model shows the evolution as cold dark matter (CDM), the w CDM model, dark matter and dark energy with a dynamical O m (z ) [where O m (z )≡[(H (z )/H0)2-1 ]/[(1 +z )3-1 ] ], and phantom dark energy with a phantom-nonphantom crossing are presented in detail. The cosmological perturbations for such evolutions are studied in the mimetic matter model. For instance, the evolution behavior of the matter density contrast (which is different than the usual one, i.e., δ ¨+2 H δ ˙-κ2ρ δ /2 =0 ) is investigated. The possibility of a peculiar evolution of δ in the model under consideration is shown. Special attention is paid to the behavior of the matter density contrast near the future singularity, where the decay of perturbations may occur much earlier than the singularity.

  12. NEC violation in mimetic cosmology revisited

    Directory of Open Access Journals (Sweden)

    Anna Ijjas

    2016-09-01

    Full Text Available In the context of Einstein gravity, if the null energy condition (NEC is satisfied, the energy density in expanding space–times always decreases while in contracting space–times the energy density grows and the universe eventually collapses into a singularity. In particular, no non-singular bounce is possible. It is, though, an open question if this energy condition can be violated in a controlled way, i.e., without introducing pathologies, such as unstable negative-energy states or an imaginary speed of sound. In this letter, we will re-examine the claim that the recently proposed mimetic scenario can violate the NEC without pathologies. We show that mimetic cosmology is prone to gradient instabilities even in cases when the NEC is satisfied (except for trivial examples. Most interestingly, the source of the instability is always the Einstein–Hilbert term in the action. The matter stress-energy component does not contribute spatial gradient terms but instead makes the problematic curvature modes dynamical. We also show that mimetic cosmology can be understood as a singular limit of known, well-behaved theories involving higher-derivative kinetic terms and discuss ways of removing the instability.

  13. NEC violation in mimetic cosmology revisited

    Science.gov (United States)

    Ijjas, Anna; Ripley, Justin; Steinhardt, Paul J.

    2016-09-01

    In the context of Einstein gravity, if the null energy condition (NEC) is satisfied, the energy density in expanding space-times always decreases while in contracting space-times the energy density grows and the universe eventually collapses into a singularity. In particular, no non-singular bounce is possible. It is, though, an open question if this energy condition can be violated in a controlled way, i.e., without introducing pathologies, such as unstable negative-energy states or an imaginary speed of sound. In this letter, we will re-examine the claim that the recently proposed mimetic scenario can violate the NEC without pathologies. We show that mimetic cosmology is prone to gradient instabilities even in cases when the NEC is satisfied (except for trivial examples). Most interestingly, the source of the instability is always the Einstein-Hilbert term in the action. The matter stress-energy component does not contribute spatial gradient terms but instead makes the problematic curvature modes dynamical. We also show that mimetic cosmology can be understood as a singular limit of known, well-behaved theories involving higher-derivative kinetic terms and discuss ways of removing the instability.

  14. Increased Olfactory Bulb BDNF Expression Does Not Rescue Deficits in Olfactory Neurogenesis in the Huntington's Disease R6/2 Mouse.

    Science.gov (United States)

    Smail, Shamayra; Bahga, Dalbir; McDole, Brittnee; Guthrie, Kathleen

    2016-03-01

    Huntington's disease (HD) is an inherited neurodegenerative disorder caused by expansion of CAG trinucleotide repeats in the huntingtin gene. Mutant huntingtin protein (mhtt) interferes with the actions of brain-derived neurotrophic factor (BDNF), and BDNF signaling is reduced in the diseased striatum. Loss of this trophic support is thought to contribute to loss of striatal medium spiny neurons in HD. Increasing BDNF in the adult striatum or ventricular ependyma slows disease progression in HD mouse models, and diverts subventricular zone (SVZ)-derived neuroblasts from their normal destination, the olfactory bulb, to the striatum, where some survive and develop features of mature neurons. Most neuroblasts that migrate to the olfactory bulb differentiate as granule cells, with approximately half surviving whereas others undergo apoptosis. In the R6/2 HD mouse model, survival of adult-born granule cells is reduced. Newly maturing cells express the BDNF receptor TrkB, suggesting that mhtt may interfere with normal BDNF trophic activity, increasing their loss. To determine if augmenting BDNF counteracts this, we examined granule cell survival in R6/2 mice that overexpress BDNF in olfactory bulb. Although we detected a decline in apoptosis, increased BDNF was not sufficient to normalize granule cell survival within their normal target in R6/2 mice. PMID:26783111

  15. The use of BDNF to enhance the patency rate of small-diameter tissue-engineered blood vessels through stem cell homing mechanisms.

    Science.gov (United States)

    Zeng, Wen; Wen, Can; Wu, Yangxiao; Li, Li; Zhou, Zhenhua; Mi, Jianhong; Chen, Wen; Yang, Mingcan; Hou, Chunli; Sun, Jiansen; Zhu, Chuhong

    2012-01-01

    The patency rate of small-diameter tissue-engineered blood vessels is the determinant for their application in coronary artery bypass grafting. The coronary artery is innervated by vagus nerves. The origin of vagus nerves is rich in brain-derived neurotrophic factors (BDNF). We have investigated whether BDNF could improve the patency rate of small-diameter tissue-engineered blood vessels through promoting stem cell homing and paracrine activity. In vitro, we isolated early and late endothelial progenitor cells (EPCs) and found BDNF could promote single clone formation and paracrine function of EPCs, and could also induce the proliferation, migration and differentiation of late EPCs. BDNF could enhance the capturing of EPCs in parallel-plate flow chamber. Flow cytometric analysis and laser-scanning confocal microscope showed BDNF could enhance the mobilization and homing of C57BL/6 mouse EPCs after wire injury. Based on it, BDNF was coupled to the lumen surface of the blood vessel matrix material incubated with collagen through SPDP to construct BDNF-modified small-diameter tissue-engineered blood vessel. The blood vessel patency rate was significantly higher than that of control group 8 weeks after implantation in rats and the endothelialization level was superior to control. These results demonstrate that BDNF can effectively improve patency of small-diameter tissue-engineered blood vessels through stem cell homing and paracrine, and it is expected to play an important role in the construction of substitutes for coronary artery bypass grafting.

  16. BDNF-induced LTP is associated with rapid Arc/Arg3.1-dependent enhancement in adult hippocampal neurogenesis.

    Science.gov (United States)

    Kuipers, Sjoukje D; Trentani, Andrea; Tiron, Adrian; Mao, Xiaosong; Kuhl, Dietmar; Bramham, Clive R

    2016-01-01

    Adult neurogenesis in the hippocampus is a remarkable phenomenon involved in various aspects of learning and memory as well as disease pathophysiology. Brain-derived neurotrophic factor (BDNF) represents a major player in the regulation of this unique form of neuroplasticity, yet the mechanisms underlying its pro-neurogenic actions remain unclear. Here, we examined the effects associated with brief (25 min), unilateral infusion of BDNF in the rat dentate gyrus. Acute BDNF infusion induced long-term potentiation (LTP) of medial perforant path-evoked synaptic transmission and, concomitantly, enhanced hippocampal neurogenesis bilaterally, reflected by increased dentate gyrus BrdU + cell numbers. Importantly, inhibition of activity-regulated cytoskeleton-associated protein (Arc/Arg3.1) translation through local, unilateral infusion of anti-sense oligodeoxynucleotides (ArcAS) prior to BDNF infusion blocked both BDNF-LTP induction and the associated pro-neurogenic effects. Notably, basal rates of proliferation and newborn cell survival were unaltered in homozygous Arc/Arg3.1 knockout mice. Taken together these findings link the pro-neurogenic effects of acute BDNF infusion to induction of Arc/Arg3.1-dependent LTP in the adult rodent dentate gyrus. PMID:26888068

  17. Effects of ganoderic acids on epileptiform discharge hippocampal neurons: insights from alterations of BDNF,TRPC3 and apoptosis.

    Science.gov (United States)

    Yang, Zhi-wei; Wu, Fei; Zhang, Sheng-Li

    2016-06-01

    Recently, Ganoderma lucidum spores (GLS) have shown anti-epileptic effects. However, there are no reports on the anti-epileptic effects of its chemical constituents ganoderic acids (GAs), and more research is needed to better understand the mechanism of GLS activity. In this work, rat primary hippocampal neurons in an in vitro model were used to assess the intervention effects of GAs on epileptiform discharge hippocampal neurons and expression of both BDNF and TRPC3, with the aid of immunofluorescence, MTT method and flow cytometry. It was found that BDNF and TRPC3 are expressed in all cells and were mainly localized in the cytoplasm. The fluorescence intensities of BDNF and TRPC3 in GAs groups were higher than those of normal control and model groups, especially at 80 μg/ml (P < 0.05). The apoptosis rate of neurons was inversely proportional to BDNF and TRPC3 changes (P < 0.01). Therefore, BDNF and TRPC3 should be involved in the occurrence and development of epilepsy. GAs might indirectly inhibit mossy fiber sprouting and adjust the synaptic reconstructions by promoting the expression of BDNF and TRPC3. Besides, GAs could exert a protective effect on hippocampal neurons by promoting neuronal survival and the recovery of injured neurons. PMID:27455554

  18. Postnatal BDNF Expression Profiles in Prefrontal Cortex and Hippocampus of a Rat Schizophrenia Model Induced by MK-801 Administration

    Directory of Open Access Journals (Sweden)

    Chunmei Guo

    2010-01-01

    Full Text Available Neonatal blockade of N-methyl-D-aspartic acid (NMDA receptors represents one of experimental animal models for schizophrenia. This study is to investigate the long-term brain-derived neurotrophic factor (BDNF expression profiles in different regions and correlation with “schizophrenia-like” behaviors in the adolescence and adult of this rat model. The NMDA receptor antagonist MK801 was administered to female Sprague-Dawley rats on postnatal days (PND 5 through 14. Open-field test was performed on PND 42, and PND 77 to examine the validity of the current model. BDNF protein levels in hippocampus and prefrontal cortex (PFC were analyzed on PND 15, PND 42, and PND 77. Results showed that neonatal challenge with MK-801 persistently elevated locomotor activity as well as BDNF expression; the alterations in BDNF expression varied at different developing stages and among brain regions. However, these findings provide neurochemical evidence that the blockade of NMDA receptors during brain development results in long-lasting alterations in BDNF expression and might contribute to neurobehavioral pathology of the present animal model for schizophrenia. Further study in the mechanisms and roles of the BDNF may lead to better understanding of the pathophysiology of schizophrenia.

  19. The CB₁ cannabinoid receptor signals striatal neuroprotection via a PI3K/Akt/mTORC1/BDNF pathway.

    Science.gov (United States)

    Blázquez, C; Chiarlone, A; Bellocchio, L; Resel, E; Pruunsild, P; García-Rincón, D; Sendtner, M; Timmusk, T; Lutz, B; Galve-Roperh, I; Guzmán, M

    2015-10-01

    The CB1 cannabinoid receptor, the main molecular target of endocannabinoids and cannabis active components, is the most abundant G protein-coupled receptor in the mammalian brain. In particular, the CB1 receptor is highly expressed in the basal ganglia, mostly on terminals of medium-sized spiny neurons, where it plays a key neuromodulatory function. The CB1 receptor also confers neuroprotection in various experimental models of striatal damage. However, the assessment of the physiological relevance and therapeutic potential of the CB1 receptor in basal ganglia-related diseases is hampered, at least in part, by the lack of knowledge of the precise mechanism of CB1 receptor neuroprotective activity. Here, by using an array of pharmacological, genetic and pharmacogenetic (designer receptor exclusively activated by designer drug) approaches, we show that (1) CB1 receptor engagement protects striatal cells from excitotoxic death via the phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin complex 1 pathway, which, in turn, (2) induces brain-derived neurotrophic factor (BDNF) expression through the selective activation of BDNF gene promoter IV, an effect that is mediated by multiple transcription factors. To assess the possible functional impact of the CB1/BDNF axis in a neurodegenerative-disease context in vivo, we conducted experiments in the R6/2 mouse, a well-established model of Huntington's disease, in which the CB1 receptor and BDNF are known to be severely downregulated in the dorsolateral striatum. Adeno-associated viral vector-enforced re-expression of the CB1 receptor in the dorsolateral striatum of R6/2 mice allowed the re-expression of BDNF and the concerted rescue of the neuropathological deficits in these animals. Collectively, these findings unravel a molecular link between CB1 receptor activation and BDNF expression, and support the relevance of the CB1/BDNF axis in promoting striatal neuron survival. PMID:25698444

  20. Social variables exert selective pressures in the evolution and form of primate mimetic musculature.

    Science.gov (United States)

    Burrows, Anne M; Li, Ly; Waller, Bridget M; Micheletta, Jerome

    2016-04-01

    Mammals use their faces in social interactions more so than any other vertebrates. Primates are an extreme among most mammals in their complex, direct, lifelong social interactions and their frequent use of facial displays is a means of proximate visual communication with conspecifics. The available repertoire of facial displays is primarily controlled by mimetic musculature, the muscles that move the face. The form of these muscles is, in turn, limited by and influenced by phylogenetic inertia but here we use examples, both morphological and physiological, to illustrate the influence that social variables may exert on the evolution and form of mimetic musculature among primates. Ecomorphology is concerned with the adaptive responses of morphology to various ecological variables such as diet, foliage density, predation pressures, and time of day activity. We present evidence that social variables also exert selective pressures on morphology, specifically using mimetic muscles among primates as an example. Social variables include group size, dominance 'style', and mating systems. We present two case studies to illustrate the potential influence of social behavior on adaptive morphology of mimetic musculature in primates: (1) gross morphology of the mimetic muscles around the external ear in closely related species of macaque (Macaca mulatta and Macaca nigra) characterized by varying dominance styles and (2) comparative physiology of the orbicularis oris muscle among select ape species. This muscle is used in both facial displays/expressions and in vocalizations/human speech. We present qualitative observations of myosin fiber-type distribution in this muscle of siamang (Symphalangus syndactylus), chimpanzee (Pan troglodytes), and human to demonstrate the potential influence of visual and auditory communication on muscle physiology. In sum, ecomorphologists should be aware of social selective pressures as well as ecological ones, and that observed morphology might

  1. From neutron stars to quark stars in mimetic gravity

    Science.gov (United States)

    Astashenok, Artyom V.; Odintsov, Sergei D.

    2016-09-01

    Realistic models of neutron and quark stars in the framework of mimetic gravity with a Lagrange multiplier constraint are presented. We discuss the effect of a mimetic scalar aiming to describe dark matter on the mass-radius relation and the moment of inertia for slowly rotating relativistic stars. The mass-radius relation and moment of inertia depend on the value of the mimetic scalar in the center of the star. This fact leads to the ambiguity in the mass-radius relation for a given equation of state. Such ambiguity allows us to explain some observational facts better than in standard general relativity. The case of mimetic potential V (ϕ )˜A eC ϕ2 is considered in detail. The relative deviation of the maximal moment of inertia is approximately twice as large as the relative deviation of the maximal stellar mass. We also briefly discuss the mimetic f (R ) gravity. In the case of f (R )=R +a R2 mimetic gravity, it is expected that the increase of maximal mass and maximal moment of inertia due to the mimetic scalar becomes much stronger with bigger parameter a . The influence of the scalar field in mimetic gravity can lead to the possible existence of extreme neutron stars with large masses.

  2. Disformal transformations, veiled General Relativity and Mimetic Gravity

    Energy Technology Data Exchange (ETDEWEB)

    Deruelle, Nathalie [APC, CNRS-Université Paris 7, 75205 Paris CEDEX 13 (France); Rua, Josephine, E-mail: deruelle@ihes.fr, E-mail: rua@cbpf.br [Instituto de Cosmologia, Relatividade e Astrofísica—ICRA/CBPF, Rua Dr. Xavier Sigaud 150, 22290-180 Rio de Janeiro (Brazil)

    2014-09-01

    In this Note we show that Einstein's equations for gravity are generically invariant under ''disformations''. We also show that the particular subclass when this is not true yields the equations of motion of ''Mimetic Gravity''. Finally we give the ''mimetic'' generalization of the Schwarzschild solution.

  3. Impaired TrkB Signaling Underlies Reduced BDNF-Mediated Trophic Support of Striatal Neurons in the R6/2 Mouse Model of Huntington's Disease.

    Science.gov (United States)

    Nguyen, Khanh Q; Rymar, Vladimir V; Sadikot, Abbas F

    2016-01-01

    The principal projection neurons of the striatum are critically dependent on an afferent supply of brain derived neurotrophic factor (BDNF) for neurotrophic support. These neurons express TrkB, the cognate receptor for BDNF, which activates signaling pathways associated with neuronal survival and phenotypic maintenance. Impairment of the BDNF-TrkB pathway is suspected to underlie the early dysfunction and prominent degeneration of striatal neurons in Huntington disease (HD). Some studies in HD models indicate that BDNF supply is reduced, while others suggest that TrkB signaling is impaired earlier in disease progression. It remains important to determine whether a primary defect in TrkB signaling underlies reduced neurotrophic support and the early vulnerability of striatal neurons in HD. Using the transgenic R6/2 mouse model of HD we found that prior to striatal degeneration there are early deficits in striatal protein levels of activated phospho-TrkB and the downstream-regulated protein DARPP-32. In contrast, total-TrkB and BDNF protein levels remained normal. Primary neurons cultured from R6/2 striatum exhibited reduced survival in response to exogenous BDNF applications. Moreover, BDNF activation of phospho-TrkB and downstream signal transduction was attenuated in R6/2 striatal cultures. These results suggest that neurotrophic support of striatal neurons is attenuated early in disease progression due to defects in TrkB signal transduction in the R6/2 model of HD. PMID:27013968

  4. A cosmological solution to mimetic dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Saadi, Hassan [American University of Beirut, Physics Department, Beirut (Lebanon)

    2016-01-15

    In this paper, a cosmological solution to Mimetic Dark Matter (MDM) for an exponential potential is provided. Then a solution for the 0 - i perturbed Einstein differential equation of MDM is obtained based on an exponential potential that satisfies inflation for some initial conditions. Another general potential is suggested that incorporates inflation too. Then quantum perturbations are included. The constants in the model can be tuned to be in agreement with the fluctuation amplitude of the cosmic microwave background (CMB) radiation. Finally, the spectral index is calculated for the suggested potentials. Moreover, MDM is shown to be a viable model to produce dark matter, inflation, and CMB's fluctuation. (orig.)

  5. A cosmological solution to mimetic dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Saadi, Hassan, E-mail: hls01@mail.aub.edu [Physics Department, American University of Beirut, Beirut (Lebanon)

    2016-01-11

    In this paper, a cosmological solution to Mimetic Dark Matter (MDM) for an exponential potential is provided. Then a solution for the 0-i perturbed Einstein differential equation of MDM is obtained based on an exponential potential that satisfies inflation for some initial conditions. Another general potential is suggested that incorporates inflation too. Then quantum perturbations are included. The constants in the model can be tuned to be in agreement with the fluctuation amplitude of the cosmic microwave background (CMB) radiation. Finally, the spectral index is calculated for the suggested potentials. Moreover, MDM is shown to be a viable model to produce dark matter, inflation, and CMB’s fluctuation.

  6. Brain-derived neurotrophic factor (BDNF) and type 2 diabetes

    DEFF Research Database (Denmark)

    Krabbe, K. S.; Nielsen, A. R.; Krogh-Madsen, R.;

    2006-01-01

    Aims/hypothesis  Decreased levels of brain-derived neurotrophic factor (BDNF) have been implicated in the pathogenesis of Alzheimer's disease and depression. These disorders are associated with type 2 diabetes, and animal models suggest that BDNF plays a role in insulin resistance. We therefore...... explored whether BDNF plays a role in human glucose metabolism. Subjects and methods  We included (Study 1) 233 humans divided into four groups depending on presence or absence of type 2 diabetes and presence or absence of obesity; and (Study 2) seven healthy volunteers who underwent both a hyperglycaemic...... and a hyperinsulinaemic-euglycaemic clamp. Results  Plasma levels of BDNF in Study 1 were decreased in humans with type 2 diabetes independently of obesity. Plasma BDNF was inversely associated with fasting plasma glucose, but not with insulin. No association was found between the BDNF G196A (Val66Met) polymorphism...

  7. The interplay of stress and sleep impacts BDNF level.

    Directory of Open Access Journals (Sweden)

    Maria Giese

    Full Text Available BACKGROUND: Sleep plays a pivotal role in normal biological functions. Sleep loss results in higher stress vulnerability and is often found in mental disorders. There is evidence that brain-derived neurotrophic factor (BDNF could be a central player in this relationship. Recently, we could demonstrate that subjects suffering from current symptoms of insomnia exhibited significantly decreased serum BDNF levels compared with sleep-healthy controls. In accordance with the paradigm indicating a link between sleep and BDNF, we aimed to investigate if the stress system influences the association between sleep and BDNF. METHODOLOGY/PRINCIPAL FINDINGS: Participants with current symptoms of insomnia plus a former diagnosis of Restless Legs Syndrome (RLS and/or Periodic Limb Movement (PLM and sleep healthy controls were included in the study. They completed questionnaires on sleep (ISI, Insomnia Severity Index and stress (PSS, Perceived Stress Scale and provided a blood sample for determination of serum BDNF. We found a significant interaction between stress and insomnia with an impact on serum BDNF levels. Moreover, insomnia severity groups and score on the PSS each revealed a significant main effect on serum BDNF levels. Insomnia severity was associated with increased stress experience affecting serum BDNF levels. Of note, the association between stress and BDNF was only observed in subjects without insomnia. Using a mediation model, sleep was revealed as a mediator of the association between stress experience and serum BDNF levels. CONCLUSIONS: This is the first study to show that the interplay between stress and sleep impacts BDNF levels, suggesting an important role of this relationship in the pathogenesis of stress-associated mental disorders. Hence, we suggest sleep as a key mediator at the connection between stress and BDNF. Whether sleep is maintained or disturbed might explain why some individuals are able to handle a certain stress load while

  8. ENDOGENOUS BDNF IN THE DORSOLATERAL STRIATUM GATES ALCOHOL DRINKING

    OpenAIRE

    Jeanblanc, Jerome; He, Dao-Yao; Carnicella, Sebastien; Kharazia, Viktor; Janak, Patricia H; Ron, Dorit

    2009-01-01

    We previously found that brain-derived neurotrophic factor (BDNF) haplodeficient mice exhibit greater ethanol-induced place preference and psychomotor sensitization, and greater ethanol consumption after deprivation. We further observed that, in mice, voluntary ethanol intake increases BDNF expression in the dorsal striatum (DS). Here, we determined whether BDNF within the DS regulates ethanol self-administration in Long Evans rats trained to self-administer a 10% ethanol solution. We observe...

  9. NEC violation in mimetic cosmology revisited

    CERN Document Server

    Ijjas, Anna; Steinhardt, Paul J

    2016-01-01

    In the context of Einstein gravity, if the null energy condition (NEC) is satisfied, the energy density in expanding space-times always decreases while in contracting space-times the energy density grows and the universe eventually collapses into a singularity. In particular, no non-singular bounce is possible. It is, though, an open question if this energy condition can be violated in a controlled way, i.e., without introducing pathologies, such as unstable negative-energy states or an imaginary speed of sound. In this paper, we will re-examine the claim that the recently proposed mimetic scenario can violate the NEC without pathologies. We show that mimetic cosmology is prone to gradient instabilities even in cases when the NEC is satisfied (except for trivial examples). Most interestingly, the source of the instability is always the Einstein-Hilbert term in the action. The matter stress-energy component does not contribute spatial gradient terms but instead makes the problematic curvature modes dynamical. ...

  10. Type I Collagen and Collagen Mimetics as Angiogenesis Promoting Superpolymers

    Energy Technology Data Exchange (ETDEWEB)

    Twardowski, T.; Fertala, A.; Orgel, J.P.R.O.; San Antonio, J.D. (TJU); (IIT); (Widener)

    2008-07-18

    Angiogenesis, the development of blood vessels from the pre-existing vasculature, is a key component of embryogenesis and tissue regeneration. Angiogenesis also drives pathologies such as tumor growth and metastasis, and hemangioma development in newborns. On the other hand, promotion of angiogenesis is needed in tissues with vascular insufficiencies, and in bioengineering, to endow tissue substitutes with appropriate microvasculatures. Therefore, much research has focused on defining mechanisms of angiogenesis, and identifying pro- and anti-angiogenic molecules. Type I collagen, the most abundant protein in humans, potently stimulates angiogenesis in vitro and in vivo. Crucial to its angiogenic activity appears to be ligation and possibly clustering of endothelial cell (EC) surface {alpha}1{beta}1/{alpha}2{beta}1 integrin receptors by the GFPGER502-507 sequence of the collagen fibril. However, additional aspects of collagen structure and function that may modulate its angiogenic properties are discussed. Moreover, type I collagen and fibrin, another angiogenic polymer, share several structural features. These observations suggest strategies for creating 'angiogenic superpolymers', including: modifying type I collagen to influence its biological half-life, immunogenicity, and integrin binding capacity; genetically engineering fibrillar collagens to include additional integrin binding sites or angiogenic determinants, and remove unnecessary or deleterious sequences without compromising fibril integrity; and exploring the suitability of poly(ortho ester), PEG-lysine copolymer, tubulin, and cholesteric cuticle as collagen mimetics, and suggesting means of modifying them to display ideal angiogenic properties. The collagenous and collagen mimetic angiogenic superpolymers described here may someday prove useful for many applications in tissue engineering and human medicine.

  11. The brain-uterus connection: brain derived neurotrophic factor (BDNF) and its receptor (Ntrk2) are conserved in the mammalian uterus.

    Science.gov (United States)

    Wessels, Jocelyn M; Wu, Liang; Leyland, Nicholas A; Wang, Hongmei; Foster, Warren G

    2014-01-01

    The neurotrophins are neuropeptides that are potent regulators of neurite growth and survival. Although mainly studied in the brain and nervous system, recent reports have shown that neurotrophins are expressed in multiple target tissues and cell types throughout the body. Additionally, dysregulation of neurotrophins has been linked to several disease conditions including Alzheimer's, Parkinson's, Huntington's, psychiatric disorders, and cancer. Brain derived neurotrophic factor (BDNF) is a member of the neurotrophin family that elicits its actions through the neurotrophic tyrosine receptor kinase type 2 (Ntrk2). Together BDNF and Ntrk2 are capable of activating the adhesion, angiogenesis, apoptosis, and proliferation pathways. These pathways are prominently involved in reproductive physiology, yet a cross-species examination of BDNF and Ntrk2 expression in the mammalian uterus is lacking. Herein we demonstrated the conserved nature of BDNF and Ntrk2 across several mammalian species by mRNA and protein sequence alignment, isolated BDNF and Ntrk2 transcripts in the uterus by Real-Time PCR, localized both proteins to the glandular and luminal epithelium, vascular smooth muscle, and myometrium of the uterus, determined that the major isoforms expressed in the human endometrium were pro-BDNF, and truncated Ntrk2, and finally demonstrated antibody specificity. Our findings suggest that BDNF and Ntrk2 are transcribed, translated, and conserved across mammalian species including human, mouse, rat, pig, horse, and the bat.

  12. Effects of the BDNF Val66Met Polymorphism and Met Allele Load on Declarative Memory Related Neural Networks

    DEFF Research Database (Denmark)

    Dodds, Chris M; Henson, Richard N; Suckling, John;

    2013-01-01

    It has been suggested that the BDNF Val66Met polymorphism modulates episodic memory performance via effects on hippocampal neural circuitry. However, fMRI studies have yielded inconsistent results in this respect. Moreover, very few studies have examined the effect of met allele load on activation...... of memory circuitry. In the present study, we carried out a comprehensive analysis of the effects of the BDNF polymorphism on brain responses during episodic memory encoding and retrieval, including an investigation of the effect of met allele load on memory related activation in the medial temporal lobe....... In contrast to previous studies, we found no evidence for an effect of BDNF genotype or met load during episodic memory encoding. Met allele carriers showed increased activation during successful retrieval in right hippocampus but this was contrast-specific and unaffected by met allele load. These results...

  13. The hydrophobic dipeptide Leu-Ile inhibits immobility induced by repeated forced swimming via the induction of BDNF.

    Science.gov (United States)

    Furukawa-Hibi, Yoko; Nitta, Atsumi; Ikeda, Takeshi; Morishita, Koji; Liu, Wenting; Ibi, Daisuke; Alkam, Tursun; Nabeshima, Toshitaka; Yamada, Kiyofumi

    2011-07-01

    Depression has recently become a serious problem in society worldwide. However, we lack appropriate therapeutic tools, since the causes of depression remain unclear. Degeneration of neuronal cells and a decrease in neurogenesis have been suggested recently as two of the factors responsible for depression-like behavior. Furthermore, brain-derived neurotrophic factor (BDNF) is also suggested to be an important factor in recovering from such behavior. We have previously demonstrated that the hydrophobic dipeptide leucyl-isoleucine (Leu-Ile) induces BDNF in cultured neuronal cells. We therefore investigated possible antidepressant-like effects of Leu-Ile in an animal model using the repeated forced swim test (FST). Mice were forced to swim for 6 min once a day in a cylinder containing water. The mice were treated with Leu-Ile s.c. or p.o. immediately after each FST. Five-day repeated Leu-Ile treatment significantly increased BDNF mRNA levels and activated the BDNF/Akt/mTOR signaling pathway in the hippocampi of the mice. While 2-week repeated FST increased immobility time, Leu-Ile treatment for 2 weeks offset this increase. In C57BL/6J-BDNF heterozygous knockout (BDNF(+/-)) mice, Leu-Ile failed to reduce the immobility time increased by repeated FST. We next investigated the extent of cell proliferation in the hippocampus as 5-bromo-2'-deoxy-uridine (BrdU) uptake into hippocampal cells. Repeated FST significantly reduced the number of BrdU-positive cells in the hippocampal dentate gyrus, while this deficit was prevented by repeated Leu-Ile treatment. These results suggest that Leu-Ile has an antidepressant-like effect, at least in part by supporting cell proliferation through the BDNF signaling pathway.

  14. AGN 191976: a novel thromboxane A2-mimetic with ocular hypotensive properties.

    Science.gov (United States)

    Krauss, A H; Woodward, D F; Chen, J; Gibson, L L; Lai, R K; Protzman, C E; Shan, T; Williams, L S; Gac, T S; Burk, R M

    1995-01-01

    The possible subdivision of thromboxane A2-sensitive (TP) receptors is currently a controversial subject. We report herein on a novel thromboxane A2 mimetic, AGN 191976, which has almost identical pharmacological activity to the well-characterized prostaglandin H2/thromboxane A2 (PGH2/TxA2) mimetic U-46619, but its effects on intraocular pressure are quite distinct from U-46619. Prostanoid receptor activity was determined in vitro using different smooth muscle assays and platelets. Intraocular pressure was measured tonometrically in ocular normotensive Beagle dogs and Cynomolgus monkeys. Conjunctival microvascular permeability was determined in guinea pigs. Despite closely resembling U-46619 as a potent and selective TP receptor agonist, AGN 191976 was a potent ocular hypotensive in dogs and monkeys whereas U-46619 did not lower IOP in either species. The ocular hypotensive effect of AGN 191976 in dogs was attenuated by pretreatment with the TP receptor antagonist SQ 29548. Thus, the ocular hypotensive effects of AGN 191976 are consistent with TP receptor stimulation. Both TxA2-mimetics caused plasma leakage in the guinea pig conjunctiva. The disparate activities of U-46619 and AGN 191976 in our studies suggest the existence of heterogeneous populations of TP-receptors in the eye.

  15. Incretin mimetics: a novel therapeutic option for patients with type 2 diabetes - a review

    DEFF Research Database (Denmark)

    Hansen, Katrine Bilberg; Vilsbøll, Tina; Knop, Filip K

    2010-01-01

    Type 2 diabetes mellitus is a metabolic disease associated with low quality of life and early death. The goal in diabetes treatment is to prevent these outcomes by tight glycemic control and minimizing vascular risk factors. So far, even intensified combination regimen with the traditional...... are initiated. Since the compounds have no insulinotropic activity at lower glucose concentrations the risk of hypoglycemia - a well-known shortcoming of existing antidiabetes treatments - is low. Additionally, incretin mimetics have been shown to be associated with beneficial effects on cardiovascular risk...... factors such as weight loss, decrease in blood pressure and changes in lipid profile. Current clinical data on the two available incretin mimetics, exenatide and liraglutide, are evaluated in this review, focusing on pharmacology, efficacy, safety and tolerability. The review is built on a systematic Pub...

  16. BDNF modulates GABAA receptors microtransplanted from the human epileptic brain to Xenopus oocytes

    Science.gov (United States)

    Palma, E.; Torchia, G.; Limatola, C.; Trettel, F.; Arcella, A.; Cantore, G.; Di Gennaro, G.; Manfredi, M.; Esposito, V.; Quarato, P. P.; Miledi, R.; Eusebi, F.

    2005-01-01

    Cell membranes isolated from brain tissues, obtained surgically from six patients afflicted with drug-resistant temporal lobe epilepsy and from one nonepileptic patient afflicted with a cerebral oligodendroglioma, were injected into frog oocytes. By using this approach, the oocytes acquire human GABAA receptors, and we have shown previously that the “epileptic receptors” (receptors transplanted from epileptic brains) display a marked run-down during repetitive applications of GABA. It was found that exposure to the neurotrophin BDNF increased the amplitude of the “GABA currents” (currents elicited by GABA) generated by the epileptic receptors and decreased their run-down; both events being blocked by K252A, a neurotrophin tyrosine kinase receptor B inhibitor. These effects of BDNF were not mimicked by nerve growth factor. In contrast, the GABAA receptors transplanted from the nonepileptic human hippocampal uncus (obtained during surgical resection as part of the nontumoral tissue from the oligodendroglioma margins) or receptors expressed by injecting rat recombinant α1β2γ2 GABAA receptor subunit cDNAs generated GABA currents whose time-course and run-down were not altered by BDNF. Loading the oocytes with the Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetate-acetoxymethyl ester (BAPTA-AM), or treating them with Rp-8-Br-cAMP, an inhibitor of the cAMP-dependent PKA, did not alter the GABA currents. However, staurosporine (a broad spectrum PK inhibitor), bisindolylmaleimide I (a PKC inhibitor), and U73122 (a phospholipase C inhibitor) blocked the BDNF-induced effects on the epileptic GABA currents. Our results indicate that BDNF potentiates the epileptic GABAA currents and antagonizes their use-dependent run-down, thus strengthening GABAergic inhibition, probably by means of activation of tyrosine kinase receptor B receptors and of both PLC and PKC. PMID:15665077

  17. Caloric Restriction Mimetics Enhance Anticancer Immunosurveillance.

    Science.gov (United States)

    Pietrocola, Federico; Pol, Jonathan; Vacchelli, Erika; Rao, Shuan; Enot, David P; Baracco, Elisa E; Levesque, Sarah; Castoldi, Francesca; Jacquelot, Nicolas; Yamazaki, Takahiro; Senovilla, Laura; Marino, Guillermo; Aranda, Fernando; Durand, Sylvère; Sica, Valentina; Chery, Alexis; Lachkar, Sylvie; Sigl, Verena; Bloy, Norma; Buque, Aitziber; Falzoni, Simonetta; Ryffel, Bernhard; Apetoh, Lionel; Di Virgilio, Francesco; Madeo, Frank; Maiuri, Maria Chiara; Zitvogel, Laurence; Levine, Beth; Penninger, Josef M; Kroemer, Guido

    2016-07-11

    Caloric restriction mimetics (CRMs) mimic the biochemical effects of nutrient deprivation by reducing lysine acetylation of cellular proteins, thus triggering autophagy. Treatment with the CRM hydroxycitrate, an inhibitor of ATP citrate lyase, induced the depletion of regulatory T cells (which dampen anticancer immunity) from autophagy-competent, but not autophagy-deficient, mutant KRAS-induced lung cancers in mice, thereby improving anticancer immunosurveillance and reducing tumor mass. Short-term fasting or treatment with several chemically unrelated autophagy-inducing CRMs, including hydroxycitrate and spermidine, improved the inhibition of tumor growth by chemotherapy in vivo. This effect was only observed for autophagy-competent tumors, depended on the presence of T lymphocytes, and was accompanied by the depletion of regulatory T cells from the tumor bed. PMID:27411589

  18. The Mimetic Principle in the Underground Economy

    Directory of Open Access Journals (Sweden)

    Cristina Voicu

    2009-08-01

    Full Text Available There has been in the recent years an increased preoccupation at international level for the research of the mechanism of development of the underground economy. The numerous vain attempts to measure the dimension of the underground economy persuaded us to embark on a qualitative research of this economic phenomenon. In our investigation on the roots of the underground economy we drew very close to the psychological and sociological aspects of the phenomenon itself. The process of humanizing that has at its origin components of the mimetic principle, like acquisitive mimesis, prompt us to ponder over J.M. Keynes’ words: „The avoidance of taxes is the only intellectual ambition that one feels rewarded for.”

  19. A role for BDNF in cocaine reward and relapse

    OpenAIRE

    Schoenbaum, Geoffrey; Stalnaker, Thomas A; Shaham, Yavin

    2007-01-01

    Brain-derived neurotrophic factor (BDNF) is important in regulating synaptic plasticity in the brain areas that process reward information. A new study reports that BDNF in the nucleus accumbens, a brain area critical for the rewarding effects of cocaine, promotes persistent cocaine-seeking behaviors and heightens relapse vulnerability.

  20. THE ROLE OF BDNF IN THE DEVELOPMENT OF FEAR LEARNING

    Science.gov (United States)

    Dincheva, Iva; Lynch, Niccola B.; Lee, Francis S.

    2016-01-01

    Brain-derived neurotrophic factor (BDNF) is a growth factor that is dynamically expressed in the brain across postnatal development, regulating neuronal differentiation and synaptic plasticity. The neurotrophic hypothesis of psychiatric mood disorders postulates that in the adult brain, decreased BDNF levels leads to altered neural plasticity, contributing to disease. Although BDNF has been established as a key factor regulating the critical period plasticity in the developing visual system, it has recently been shown to also play a role in fear circuitry maturation, which has implications for the emergence of fear-related mood disorders. This review provides a detailed overview of developmental changes in expression of BDNF isoforms, as well as their receptors across postnatal life. In addition, recent developmental studies utilizing a genetic BDNF single nucleotide polymorphism (Val66Met) knock-in mouse highlight the impact of BDNF on fear learning during a sensitive period spanning the transition into adolescent time frame. We hypothesize that BDNF in the developing brain regulates fear circuit plasticity during a sensitive period in early adolescence, and alterations in BDNF expression (genetic or environmental) have a persistent impact on fear behavior and fear-related disorders. PMID:27699937

  1. The mimetic finite difference method for elliptic problems

    CERN Document Server

    Veiga, Lourenço Beirão; Manzini, Gianmarco

    2014-01-01

    This book describes the theoretical and computational aspects of the mimetic finite difference method for a wide class of multidimensional elliptic problems, which includes diffusion, advection-diffusion, Stokes, elasticity, magnetostatics and plate bending problems. The modern mimetic discretization technology developed in part by the Authors allows one to solve these equations on unstructured polygonal, polyhedral and generalized polyhedral meshes. The book provides a practical guide for those scientists and engineers that are interested in the computational properties of the mimetic finite difference method such as the accuracy, stability, robustness, and efficiency. Many examples are provided to help the reader to understand and implement this method. This monograph also provides the essential background material and describes basic mathematical tools required to develop further the mimetic discretization technology and to extend it to various applications.

  2. A Finite Element Framework for Some Mimetic Finite Difference Discretizations

    OpenAIRE

    Rodrigo, Carmen; Gaspar, Francisco; Hu, Xiaozhe; Zikatanov, Ludmil

    2015-01-01

    In this work we derive equivalence relations between mimetic finite difference schemes on simplicial grids and modified N\\'ed\\'elec-Raviart-Thomas finite element methods for model problems in $\\mathbf{H}(\\operatorname{\\mathbf{curl}})$ and $H(\\operatorname{div})$. This provides a simple and transparent way to analyze such mimetic finite difference discretizations using the well-known results from finite element theory. The finite element framework that we develop is also crucial for the design...

  3. Endurance training enhances BDNF release from the human brain

    DEFF Research Database (Denmark)

    Seifert, Thomas; Brassard, Patrice; Wissenberg, Mads;

    2010-01-01

    The circulating level of brain-derived neurotrophic factor (BDNF) is reduced in patients with major depression and type-2 diabetes. Because acute exercise increases BDNF production in the hippocampus and cerebral cortex, we hypothesized that endurance training would enhance the release of BDNF from...... the human brain as detected from arterial and internal jugular venous blood samples. In a randomized controlled study, 12 healthy sedentary males carried out 3 mo of endurance training (n = 7) or served as controls (n = 5). Before and after the intervention, blood samples were obtained at rest and during...... exercise. At baseline, the training group (58 + or - 106 ng x 100 g(-1) x min(-1), means + or - SD) and the control group (12 + or - 17 ng x 100 g(-1) x min(-1)) had a similar release of BDNF from the brain at rest. Three months of endurance training enhanced the resting release of BDNF to 206 + or - 108...

  4. From neutron stars to quark stars in mimetic gravity

    CERN Document Server

    Astashenok, A V

    2015-01-01

    Realistic models of neutron and quark stars in the framework of mimetic gravity with Lagrange multiplier constraint are presented. We discuss the effect of mimetic scalar aiming to describe dark matter on mass-radius relation and the moment of inertia for slowly rotating relativistic stars. The mass-radius relation and moment of inertia depend on the value of mimetic scalar in the center of star. This fact leads to the ambiguity in the mass-radius relation for a given equation of state. {Such ambiguity allows to explain some observational facts better than in standard General Relativity}. The case of two mimetic potentials namely $V(\\phi)\\sim A\\phi^{-2}$ and $V(\\phi)\\sim Ae^{B\\phi^{2}}$ is considered in detail. The relative deviation of maximal moment of inertia is approximately twice larger than the relative deviation of maximal stellar mass. We also briefly discuss the mimetic $f(R)$ gravity. In the case of $f(R)=R+aR^2$ mimetic gravity it is expected that increase of maximal mass and maximal moment of iner...

  5. Brain-derived neurotrophic factor (BDNF) enhances GABA transport by modulating the trafficking of GABA transporter-1 (GAT-1) from the plasma membrane of rat cortical astrocytes

    DEFF Research Database (Denmark)

    Vaz, Sandra H; Jørgensen, Trine Nygaard; Cristóvão-Ferreira, Sofia;

    2011-01-01

    The ¿-aminobutyric acid (GABA) transporters (GATs) are located in the plasma membrane of neurons and astrocytes and are responsible for termination of GABAergic transmission. It has previously been shown that brain derived neurotrophic factor (BDNF) modulates GAT-1-mediated GABA transport in nerve...... terminals and neuronal cultures. We now report that BDNF enhances GAT-1-mediated GABA transport in cultured astrocytes, an effect mostly due to an increase in the V(max) kinetic constant. This action involves the truncated form of the TrkB receptor (TrkB-t) coupled to a non-classic PLC-¿/PKC-d and ERK....../MAPK pathway and requires active adenosine A(2A) receptors. Transport through GAT-3 is not affected by BDNF. To elucidate if BDNF affects trafficking of GAT-1 in astrocytes, we generated and infected astrocytes with a functional mutant of the rat GAT-1 (rGAT-1) in which the hemagglutinin (HA) epitope...

  6. Apolipoprotein Mimetic Peptides: A New Approach for the Treatment of Asthma

    Directory of Open Access Journals (Sweden)

    Xianglan eYao

    2012-03-01

    Full Text Available New treatments are needed for severe asthmatics to improve disease control and avoid severe toxicities associated with oral corticosteroids. We have used a murine model of house dust mite (HDM-induced asthma to identify steroid-unresponsive genes that might represent targets for new therapeutic approaches for severe asthma. This strategy identified apolipoprotein E as a steroid-unresponsive gene with increased mRNA expression in the lungs of HDM-challenged mice. Furthermore, apolipoprotein E functioned as an endogenous negative regulator of airway hyperreactivity and goblet cell hyperplasia in experimental HDM-induced asthma. The ability of apolipoprotein E, which is expressed by lung macrophages, to attenuate AHR and goblet cell hyperplasia is mediated by low density lipoprotein (LDL receptors expressed by airway epithelial cells. Consistent with this, administration of an apolipoprotein E mimetic peptide, corresponding to amino acids 130 to 149 of the LDL receptor-binding domain of the holo-apoE protein, significantly reduced AHR and goblet cell hyperplasia in HDM-challenged apoE-/- mice. These findings identified the apolipoprotein E - LDL receptor pathway as a new druggable target for asthma that can be activated by administration of apoE mimetic peptides. Similarly, apolipoprotein A-I may have therapeutic potential in asthma based upon its anti-inflammatory, anti-oxidative and anti-fibrotic properties. Furthermore, administration of apolipoprotein A-I mimetic peptides has attenuated airway inflammation, airway remodeling and airway hyperreactivity in murine models of experimental asthma. Thus, site-directed delivery of inhaled apolipoprotein E or apolipoprotein A-I mimetic peptides may represent novel treatment approaches that can be developed for asthma, including severe disease.

  7. Dysregulation of TrkB phosphorylation and proBDNF protein in adenylyl cyclase 1 and 8 knockout mice in a model of fetal alcohol spectrum disorder.

    Science.gov (United States)

    Susick, Laura L; Chrumka, Alexandria C; Hool, Steven M; Conti, Alana C

    2016-03-01

    Brain-derived neurotrophic factor (BDNF) mediates neuron growth and is regulated by adenylyl cyclases (ACs). Mice lacking AC1/8 (DKO) have a basal reduction in the dendritic complexity of medium spiny neurons in the caudate putamen and demonstrate increased neurotoxicity in the striatum following acute neonatal ethanol exposure compared to wild type (WT) controls, suggesting a compromise in BDNF regulation under varying conditions. Although neonatal ethanol exposure can negatively impact BDNF expression, little is known about the effect on BDNF receptor activation and its downstream signaling, including Akt activation, an established neuroprotective pathway. Therefore, here we determined the effects of AC1/8 deletion and neonatal ethanol administration on BDNF and proBDNF protein expression, and activation of tropomyosin-related kinase B (TrkB), Akt, ERK1/2, and PLCγ. WT and DKO mice were treated with a single dose of 2.5 g/kg ethanol or saline at postnatal days 5-7 to model late-gestational alcohol exposure. Striatal and cortical tissues were analyzed using a BDNF enzyme-linked immunosorbent assay or immunoblotting for proBDNF, phosphorylated and total TrkB, Akt, ERK1/2, and PLCɣ1. Neither postnatal ethanol exposure nor AC1/8 deletion affected total BDNF protein expression at any time point in either region examined. Neonatal ethanol increased the expression of proBDNF protein in the striatum of WT mice 6, 24, and 48 h after exposure, with DKO mice demonstrating a reduction in proBDNF expression 6 h after exposure. Six and 24 h after ethanol administration, phosphorylation of full-length TrkB in the striatum was significantly reduced in WT mice, but was significantly increased in DKO mice only at 24 h. Interestingly, 48 h after ethanol, both WT and DKO mice demonstrated a reduction in phosphorylated full-length TrkB. In addition, Akt and PLCɣ1 phosphorylation was also decreased in ethanol-treated DKO mice 48 h after injection. These data demonstrate

  8. Effect of miR-185 * on BDNF/TrkB signaling pathway expression in epileptic neurons%miR-185∗对癫痫海马神经元中 BDNF-TrkB 通路表达的影响

    Institute of Scientific and Technical Information of China (English)

    蔡浩; 李江丽; 谢伟; 常伟; 宋毅军

    2015-01-01

    ABSTRACT:Objective To study the BDNF/TrkB signaling pathway in the epilepsy model of hippocampal neurons and the regulatory effect of on it.Methods The primary hippocampal neurons cultured in vitro for 7 days were randomly divided into seven groups:control group,epilepsy group,control+BDNF group,epilepsy+BDNF group,control + miR-185 ∗ group,epilepsy + miR-185 ∗ group,and epilepsy + miR-185 ∗ + BDNF group.We constructed miR-185 ∗ lentivirus vector and observed the changes of BDNF/TrkB pathway expression after transfaction of miR-185 ∗ by immunohistochemistry,patch clamp technique and Western blot technique.Results Compared with the control+BDNF group,the phosphorylated TrkB (pTrkB)/TrkB value was significantly lower in epilepsy+BDNF group (P < 0.05 )and control group (P < 0.001 ).Compared with the epilepsy group,the phosphorylated TrkB (pTrkB)/TrkB value was significantly higher in epilepsy+BDNF group (P <0.05).Compared with the epilepsy+miR-185 ∗ +BDNF group,the phosphorylated TrkB (pTrkB)/TrkB value was significantly lower in epilepsy + BDNF group and epilepsy + miR-185 ∗ group (P < 0.001 ).BDNF could promote the signaling conduction and miR-185 ∗ could remove the inhibition of BDNF/TrkB signaling.Conclusion BDNF can activate the BDNF/TrkB signaling pathway and transfection with miR-185 ∗ can relieve the inhibition of BDNF/TrkB signaling pathway of epileptic state by up-regulating the expression of TrkB.%目的:研究海马神经元癫痫模型中的 BDNF/TrkB 信号通路及 miR-185∗对其的调控。方法构建 miR-185∗表达载体。体外培养海马神经元,7 d 后将其随机分为正常组、癫痫组、正常+BDNF 组、癫痫+BDNF 组、正常转染miR-185∗ 组、癫痫转染 miR-185∗ 组、癫痫转染 miR-185∗ +BDNF 组。免疫荧光、膜片钳及免疫印迹技术观察转染miR-185∗ 后 BDNF/TrkB 通路的表达变化。结果癫痫+BDNF 组海马神经元细胞的 TrkB 蛋白磷酸化水平较正常+BDNF

  9. Working Memory Deficits, Increased Anxiety-Like Traits, and Seizure Susceptibility in BDNF Overexpressing Mice

    Science.gov (United States)

    Papaleo, Francesco; Silverman, Jill L.; Aney, Jordan; Tian, Qingjun; Barkan, Charlotte L.; Chadman, Kathryn K.; Crawley, Jacqueline N.

    2011-01-01

    BDNF regulates components of cognitive processes and has been implicated in psychiatric disorders. Here we report that genetic overexpression of the BDNF mature isoform (BDNF-tg) in female mice impaired working memory functions while sparing components of fear conditioning. BDNF-tg mice also displayed reduced breeding efficiency, higher…

  10. BDNF serum levels, but not BDNF Val66Met genotype, are correlated with personality traits in healthy subjects.

    Science.gov (United States)

    Minelli, Alessandra; Zanardini, Roberta; Bonvicini, Cristian; Sartori, Riccardo; Pedrini, Laura; Gennarelli, Massimo; Bocchio-Chiavetto, Luisella

    2011-08-01

    Consisting evidence in animal models has suggested that alterations in brain-derived neurotrophic factor (BDNF) brain expression and release are involved in the pathogenesis of mental illnesses, such as, mood, anxiety, and eating disorders. This hypothesis is supported by data emerging from biochemical studies on serum BDNF levels and genetic studies on the functional polymorphism Val66Met in the BDNF gene in patients and control subjects. Anxiety-related personality traits are associated with several mental disorders. However, they are also measurable in non-affected subjects and, so, may represent a useful "endophenotype" to study the biological correlation of the vulnerability factors in the general population. In this study, we analyzed putative correlations in subjects unaffected by mental disorders between personality traits, serum BDNF levels (N = 107), and the BDNF Val66Met genotype (N = 217). Furthermore, we tested the possible interactions between these variables. A significant correlation has been observed between high scores of harm avoidance (HA) measured by the temperament and character inventory (TCI), and low BDNF serum concentration (r = -0.253, P = 0.009). In addition, an association has been evidenced between low BDNF levels in serum and the BDNF Val/Val genotype (P = 0.021). By analyzing putative concomitant effects of different variables on HA scores in a regression model, we observed a significant correlation only with BDNF serum concentrations (P = 0.022). The study results suggest that a decrease in serum BDNF concentrations may represent a biochemical marker associated with anxiety personality traits also retrievable in the general population.

  11. Abnormal hippocampal BDNF and miR-16 expression is associated with depression-like behaviors induced by stress during early life.

    Directory of Open Access Journals (Sweden)

    Mei Bai

    Full Text Available Some environmental stressors lead to the onset of depression via inhibiting hippocampal BDNF expression, but other environmental stressors-induced depression exhibits no change in BDNF expression. The underlying mechanisms behind the divergence remain unknown. In this study, depression-like behaviors were induced in rats by maternal deprivation (MD and chronic unpredictable stress (CUPS. Depression-like behaviors were tested by open field test, forced swimming test, and sucrose consumption test. BDNF and miR-16 expressions in the hippocampus were examined by real-time PCR. MD and CUPS rats crawled less distance, exhibited decreased vertical activity, and produced more fecal pellets than control rats in the open field test. However, MD rats crawled less distance and produced significantly less fecal pellets than CUPS rats. In the forced swimming and sucrose consumption tests, CUPS and MD rats exhibited longer floating time and consumed less sucrose than control rats, but MD rats exhibited shorter floating time and consumed less sucrose than CUPS rats. MD but not CUPS rats showed lower BDNF mRNA and higher miR-16 expression than control rats. In MD rats, BDNF mRNA expression negatively correlated with the expression of miR-16. BDNF expression positively correlated with the total distance rats crawled and vertical activity in the open field test while miR-16 expression negatively correlated the two behaviors. BDNF positively correlated with sucrose preference rate while miR-16 negatively correlated with sucrose preference rate of the sucrose consumption test. Our study suggests that MD and CUPS induced different depression-like behaviors in rats. Depression induced by MD but not CUPS was significantly associated with upregulation of miR-16 and possibly subsequent downregulation of BDNF in hippocampus.

  12. BDNF downregulates 5-HT(2A) receptor protein levels in hippocampal cultures

    DEFF Research Database (Denmark)

    Trajkovska, V; Santini, M A; Marcussen, Anders Bue;

    2009-01-01

    Both brain-derived neurotrophic factor (BDNF) and the serotonin receptor 2A (5-HT(2A)) have been related to depression pathology. Specific 5-HT(2A) receptor changes seen in BDNF conditional mutant mice suggest that BDNF regulates the 5-HT(2A) receptor level. Here we show a direct effect of BDNF...... on 5-HT(2A) receptor protein levels in primary hippocampal neuronal and mature hippocampal organotypic cultures exposed to different BDNF concentrations for either 1, 3, 5 or 7 days. In vivo effects of BDNF on hippocampal 5-HT(2A) receptor levels were further corroborated in (BDNF +/-) mice...... with reduced BDNF levels. In primary neuronal cultures, 7 days exposure to 25 and 50ng/mL BDNF resulted in downregulation of 5-HT(2A), but not of 5-HT(1A), receptor protein levels. The BDNF-associated downregulation of 5-HT(2A) receptor levels was also observed in mature hippocampal organotypic cultures...

  13. Motoneuron BDNF/TrkB Signaling Enhances Functional Recovery after Cervical Spinal Cord Injury

    OpenAIRE

    Mantilla, Carlos B.; Gransee, Heather M.; Zhan, Wen-Zhi; Sieck, Gary C.

    2013-01-01

    A C2 cervical spinal cord hemisection (SH) interrupts descending inspiratory-related drive to phrenic motoneurons located between C3 and C5 in rats, paralyzing the ipsilateral hemidiaphragm muscle. There is gradual recovery of rhythmic diaphragm muscle activity ipsilateral to cervical spinal cord injury over time, consistent with neuroplasticity and strengthening of spared, contralateral descending premotor input to phrenic motoneurons. Brainderived neurotrophic factor (BDNF) signaling throug...

  14. Aerobic exercise improves hippocampal function and increases BDNF in the serum of young adult males

    OpenAIRE

    WARMINGTON, STUART; O'Mara, Shane; GRIFFIN, EADAOIN; KELLY, AINE

    2011-01-01

    PUBLISHED Physical activity has been reported to improve cognitive function in humans and rodents, possibly via a brain-derived neurotrophic factor (BDNF)-regulated mechanism. In this study of human subjects, we have assessed the effects of acute and chronic exercise on performance of a face-name matching task, which recruits the hippocampus and associated structures of the medial temporal lobe, and the Stroop word-colour task, which does not, and have assessed circulating concentrations o...

  15. The responsiveness of TrkB to BDNF and antidepressant drugs is differentially regulated during mouse development.

    Directory of Open Access Journals (Sweden)

    Antonio Di Lieto

    Full Text Available BACKGROUND: Previous studies suggest that the responsiveness of TrkB receptor to BDNF is developmentally regulated in rats. Antidepressant drugs (AD have been shown to increase TrkB signalling in the adult rodent brain, and recent findings implicate a BDNF-independent mechanism behind this phenomenon. When administered during early postnatal life, ADs produce long-lasting biochemical and behavioural alterations that are observed in adult animals. METHODOLOGY: We have here examined the responsiveness of brain TrkB receptors to BDNF and ADs during early postnatal life of mouse, measured as autophosphorylation of TrkB (pTrkB. PRINCIPAL FINDINGS: We found that ADs fail to induce TrkB signalling before postnatal day 12 (P12 after which an adult response of TrkB to ADs was observed. Interestingly, there was a temporally inverse correlation between the appearance of the responsiveness of TrkB to systemic ADs and the marked developmental reduction of BDNF-induced TrkB in brain microslices ex vivo. Basal p-TrkB status in the brain of BDNF deficient mice was significantly reduced only during early postnatal period. Enhancing cAMP (cyclic adenosine monophosphate signalling failed to facilitate TrkB responsiveness to BDNF. Reduced responsiveness of TrkB to BDNF was not produced by the developmental increase in the expression of dominant-negative truncated TrkB.T1 because this reduction was similarly observed in the brain microslices of trkB.T1(-/- mice. Moreover, postnatal AD administration produced long-lasting behavioural alterations observable in adult mice, but the responses were different when mice were treated during the time when ADs did not (P4-9 or did (P16-21 activate TrkB. CONCLUSIONS: We have found that ADs induce the activation of TrkB only in mice older than 2 weeks and that responsiveness of brain microslices to BDNF is reduced during the same time period. Exposure to ADs before and after the age when ADs activate TrkB produces differential

  16. Increased BDNF levels in long-term bipolar disorder patients

    Directory of Open Access Journals (Sweden)

    Izabela Guimarães Barbosa

    2013-03-01

    Full Text Available INTRODUCTION: Bipolar disorder (BD is a prevalent, chronic and progressive illness. There is a growing body of evidence indicating that brain-derived neurotrophic factor (BDNF plays an important role in the pathophysiology of BD. OBJECTIVE: The aim of this study was to evaluate BDNF plasma levels in BD patients with long term illness in comparison with controls. METHODS: 87 BD type I patients and 58 controls matched by age, gender and education level were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatric Interview and the patients by the Young Mania Rating Scale and the Hamilton Depression Rating Scale. The plasma levels of BDNF were measured by ELISA. RESULTS: On average, patients had suffered from BD for 23.4 years. In comparison with controls, BD patients with mania presented a 1.90-fold increase in BDNF plasma levels (p = .001, while BD patients in remission presented a 1.64-fold increase in BDNF plasma levels (p = .03. BDNF plasma levels were not influenced by age, length of illness or current medications. CONCLUSIONS: The present study suggests that long-term BD patients exhibit increased circulating levels of BDNF.

  17. Theoretical studies on the interactions of XIAP-BIR3 domain with bicyclic and tricyclic core monovalent Smac mimetics.

    Science.gov (United States)

    Ling, Baoping; Dong, Lihua; Zhang, Rui; Wang, Zhiguo; Liu, Yongjun; Liu, Chengbu

    2010-11-01

    X-linked IAP can bind caspase-9 and inhibit its activity. Mitochondrial protein Smac/DIABLO can also interact with XIAP and relieve the inhibition on caspase-9 to induce apoptosis. A series of artificial Smac mimetics have been used to mimic the Smac N-terminal tetrapeptide AVPI to bind to XIAP-BIR3, but these structural diverse mimetics exhibited distinct binding affinities. To get an insight into the binding nature and optimize the structures, molecular docking and dynamics simulations were used to study the binding of XIAP-BIR3 with three groups of Smac mimetics. The docking results reveal that these Smac mimetics anchored on the surface groove of XIAP-BIR3 and superimposed well with AVPI. The modifications on the seven-membered ring of bicyclic core segment do not strengthen the binding affinity, while a benzyl introduced to the five-membered ring is favorable to the binding. Molecular dynamics simulations on three typical systems show that these complexes are very stable. Hydrogen bonds between the bicyclic core segment and Thr308 play critical roles in maintaining the stability of complex. The binding free energies calculated by MM_PBSA method are consistent with the experimental results. PMID:20980180

  18. An overview on antidiabetic medicinal plants having insulin mimetic property

    Directory of Open Access Journals (Sweden)

    DK Patel

    2012-04-01

    Full Text Available Diabetes mellitus is one of the common metabolic disorders acquiring around 2.8% of the world's population and is anticipated to cross 5.4% by the year 2025. Since long back herbal medicines have been the highly esteemed source of medicine therefore, they have become a growing part of modern, high-tech medicine. In view of the above aspects the present review provides profiles of plants (65 species with hypoglycaemic properties, available through literature source from various database with proper categorization according to the parts used, mode of reduction in blood glucose (insulinomimetic or insulin secretagogues activity and active phytoconstituents having insulin mimetics activity. From the review it was suggested that, plant showing hypoglycemic potential mainly belongs to the family Leguminoseae, Lamiaceae, Liliaceae, Cucurbitaceae, Asteraceae, Moraceae, Rosaceae and Araliaceae. The most active plants are Allium sativum, Gymnema sylvestre, Citrullus colocynthis, Trigonella foenum greacum, Momordica charantia and Ficus bengalensis. The review describes some new bioactive drugs and isolated compounds from plants such as roseoside, epigallocatechin gallate, beta-pyrazol-1-ylalanine, cinchonain Ib, leucocyandin 3-O-beta-d-galactosyl cellobioside, leucopelargonidin-3-O-alpha-L rhamnoside, glycyrrhetinic acid, dehydrotrametenolic acid, strictinin, isostrictinin, pedunculagin, epicatechin and christinin-A showing significant insulinomimetic and antidiabetic activity with more efficacy than conventional hypoglycaemic agents. Thus, from the review majorly, the antidiabetic activity of medicinal plants is attributed to the presence of polyphenols, flavonoids, terpenoids, coumarins and other constituents which show reduction in blood glucose levels. The review also discusses the management aspect of diabetes mellitus using these plants and their active principles.

  19. An overview on antidiabetic medicinal plants having insulin mimetic property

    Institute of Scientific and Technical Information of China (English)

    Patel DK; Prasad SK; Kumar R; Hemalatha S

    2012-01-01

    Diabetes mellitus is one of the common metabolic disorders acquiring around 2.8% of the world’s population and is anticipated to cross 5.4% by the year 2025. Since long back herbal medicines have been the highly esteemed source of medicine therefore, they have become a growing part of modern, high-tech medicine. In view of the above aspects the present review provides profiles of plants (65 species) with hypoglycaemic properties, available through literature source from various database with proper categorization according to the parts used, mode of reduction in blood glucose (insulinomimetic or insulin secretagogues activity) and active phytoconstituents having insulin mimetics activity. From the review it was suggested that, plant showing hypoglycemic potential mainly belongs to the family Leguminoseae, Lamiaceae, Liliaceae, Cucurbitaceae, Asteraceae, Moraceae, Rosaceae and Araliaceae. The most active plants are Allium sativum, Gymnema sylvestre, Citrullus colocynthis, Trigonella foenum greacum, Momordica charantia and Ficus bengalensis. The review describes some new bioactive drugs and isolated compounds from plants such as roseoside, epigallocatechin gallate, beta-pyrazol-1-ylalanine, cinchonain Ib, leucocyandin 3-O-beta-d-galactosyl cellobioside, leucopelargonidin-3- O-alpha-L rhamnoside, glycyrrhetinic acid, dehydrotrametenolic acid, strictinin, isostrictinin, pedunculagin, epicatechin and christinin-A showing significant insulinomimetic and antidiabetic activity with more efficacy than conventional hypoglycaemic agents. Thus, from the review majorly, the antidiabetic activity of medicinal plants is attributed to the presence of polyphenols, flavonoids, terpenoids, coumarins and other constituents which show reduction in blood glucose levels. The review also discusses the management aspect of diabetes mellitus using these plants and their active principles.

  20. An overview on antidiabetic medicinal plants having insulin mimetic property.

    Science.gov (United States)

    Patel, D K; Prasad, S K; Kumar, R; Hemalatha, S

    2012-04-01

    Diabetes mellitus is one of the common metabolic disorders acquiring around 2.8% of the world's population and is anticipated to cross 5.4% by the year 2025. Since long back herbal medicines have been the highly esteemed source of medicine therefore, they have become a growing part of modern, high-tech medicine. In view of the above aspects the present review provides profiles of plants (65 species) with hypoglycaemic properties, available through literature source from various database with proper categorization according to the parts used, mode of reduction in blood glucose (insulinomimetic or insulin secretagogues activity) and active phytoconstituents having insulin mimetics activity. From the review it was suggested that, plant showing hypoglycemic potential mainly belongs to the family Leguminoseae, Lamiaceae, Liliaceae, Cucurbitaceae, Asteraceae, Moraceae, Rosaceae and Araliaceae. The most active plants are Allium sativum, Gymnema sylvestre, Citrullus colocynthis, Trigonella foenum greacum, Momordica charantia and Ficus bengalensis. The review describes some new bioactive drugs and isolated compounds from plants such as roseoside, epigallocatechin gallate, beta-pyrazol-1-ylalanine, cinchonain Ib, leucocyandin 3-O-beta-d-galactosyl cellobioside, leucopelargonidin-3- O-alpha-L rhamnoside, glycyrrhetinic acid, dehydrotrametenolic acid, strictinin, isostrictinin, pedunculagin, epicatechin and christinin-A showing significant insulinomimetic and antidiabetic activity with more efficacy than conventional hypoglycaemic agents. Thus, from the review majorly, the antidiabetic activity of medicinal plants is attributed to the presence of polyphenols, flavonoids, terpenoids, coumarins and other constituents which show reduction in blood glucose levels. The review also discusses the management aspect of diabetes mellitus using these plants and their active principles.

  1. Hydrogen Sulfide Protects against Chronic Unpredictable Mild Stress-Induced Oxidative Stress in Hippocampus by Upregulation of BDNF-TrkB Pathway

    Science.gov (United States)

    Zou, Wei; Wang, Chun-Yan; Tan, Hui-Ying; Zeng, Hai-Ying; Zhang, Ping; Gu, Hong-Feng

    2016-01-01

    Chronic unpredictable mild stress (CUMS) induces hippocampal oxidative stress. H2S functions as a neuroprotectant against oxidative stress in brain. We have previously shown the upregulatory effect of H2S on BDNF protein expression in the hippocampus of rats. Therefore, we hypothesized that H2S prevents CUMS-generated oxidative stress by upregulation of BDNF-TrkB pathway. We showed that NaHS (0.03 or 0.1 mmol/kg/day) ameliorates the level of hippocampal oxidative stress, including reduced levels of malondialdehyde (MDA) and 4-hydroxy-2-trans-nonenal (4-HNE), as well as increased level of glutathione (GSH) and activity of superoxide dismutase (SOD) in the hippocampus of CUMS-treated rats. We also found that H2S upregulated the level of BDNF and p-TrkB protein in the hippocampus of CUMS rats. Furthermore, inhibition of BDNF signaling by K252a, an inhibitor of the BDNF receptor TrkB, blocked the antioxidant effects of H2S on CUMS-induced hippocampal oxidative stress. These results reveal the inhibitory role of H2S in CUMS-induced hippocampal oxidative stress, which is through upregulation of BDNF/TrkB pathway. PMID:27525050

  2. Paternal alcohol exposure in mice alters brain NGF and BDNF and increases ethanol-elicited preference in male offspring.

    Science.gov (United States)

    Ceccanti, Mauro; Coccurello, Roberto; Carito, Valentina; Ciafrè, Stefania; Ferraguti, Giampiero; Giacovazzo, Giacomo; Mancinelli, Rosanna; Tirassa, Paola; Chaldakov, George N; Pascale, Esterina; Ceccanti, Marco; Codazzo, Claudia; Fiore, Marco

    2016-07-01

    Ethanol (EtOH) exposure during pregnancy induces cognitive and physiological deficits in the offspring. However, the role of paternal alcohol exposure (PAE) on offspring EtOH sensitivity and neurotrophins has not received much attention. The present study examined whether PAE may disrupt nerve growth factor (NGF) and/or brain-derived neurotrophic factor (BDNF) and affect EtOH preference/rewarding properties in the male offspring. CD1 sire mice were chronically addicted for EtOH or administered with sucrose. Their male offsprings when adult were assessed for EtOH preference by a conditioned place preference paradigm. NGF and BDNF, their receptors (p75(NTR) , TrkA and TrkB), dopamine active transporter (DAT), dopamine receptors D1 and D2, pro-NGF and pro-BDNF were also evaluated in brain areas. PAE affected NGF levels in frontal cortex, striatum, olfactory lobes, hippocampus and hypothalamus. BDNF alterations in frontal cortex, striatum and olfactory lobes were found. PAE induced a higher susceptibility to the EtOH rewarding effects mostly evident at the lower concentration (0.5 g/kg) that was ineffective in non-PAE offsprings. Moreover, higher ethanol concentrations (1.5 g/kg) produced an aversive response in PAE animals and a significant preference in non-PAE offspring. PAE affected also TrkA in the hippocampus and p75(NTR) in the frontal cortex. DAT was affected in the olfactory lobes in PAE animals treated with 0.5 g/kg of ethanol while no differences were found on D1/D2 receptors and for pro-NGF or pro-BDNF. In conclusion, this study shows that: PAE affects NGF and BDNF expression in the mouse brain; PAE may induce ethanol intake preference in the male offspring. PMID:25940002

  3. No exercise-induced increase in serum BDNF after cycling near a major traffic road.

    Science.gov (United States)

    Bos, I; Jacobs, L; Nawrot, T S; de Geus, B; Torfs, R; Int Panis, L; Degraeuwe, B; Meeusen, R

    2011-08-15

    Commuting by bike has a clear health enhancing effect. Moreover, regular exercise is known to improve brain plasticity, which results in enhanced cognition and memory performance. Animal research has clearly shown that exercise upregulates brain-derived neurotrophic factor (BDNF - a neurotrophine) enhancing brain plasticity. Studies in humans found an increase in serum BDNF concentration in response to an acute exercise bout. Recently, more evidence is emerging suggesting that exposure to air pollution (such as particulate matter (PM)) is higher in commuter cyclists compared to car drivers. Furthermore, exposure to PM is linked to negative neurological effects, such as neuroinflammation and cognitive decline. We carried-out a cross-over experiment to examine the acute effect of exercise on serum BDNF, and the potential effect-modification by exposure to traffic-related air pollution. Thirty eight physically fit, non-asthmatic volunteers (mean age: 43, 26% women) performed two cycling trials, one near a major traffic road (Antwerp Ring, R1, up to 260,000 vehicles per day) and one in an air-filtered room. The air-filtered room was created by reducing fine particles as well as ultrafine particles (UFP). PM10, PM2.5 and UFP were measured. The duration (∼20min) and intensity of cycling were kept the same for each volunteer for both cycling trials. Serum BDNF concentrations were measured before and 30min after each cycling trial. Average concentrations of PM10 and PM2.5 were 64.9μg/m(3) and 24.6μg/m(3) in cycling near a major ring way, in contrast to 7.7μg/m(3) and 2.0μg/m(3) in the air-filtered room. Average concentrations of UFP were 28,180 particles/cm(3) along the road in contrast to 496 particles/cm(3) in the air-filtered room. As expected, exercise significantly increased serum BDNF concentration after cycling in the air-filtered room (+14.4%; p=0.02). In contrast, serum BDNF concentrations did not increase after cycling near the major traffic route (+0.5%; p

  4. No exercise-induced increase in serum BDNF after cycling near a major traffic road.

    Science.gov (United States)

    Bos, I; Jacobs, L; Nawrot, T S; de Geus, B; Torfs, R; Int Panis, L; Degraeuwe, B; Meeusen, R

    2011-08-15

    Commuting by bike has a clear health enhancing effect. Moreover, regular exercise is known to improve brain plasticity, which results in enhanced cognition and memory performance. Animal research has clearly shown that exercise upregulates brain-derived neurotrophic factor (BDNF - a neurotrophine) enhancing brain plasticity. Studies in humans found an increase in serum BDNF concentration in response to an acute exercise bout. Recently, more evidence is emerging suggesting that exposure to air pollution (such as particulate matter (PM)) is higher in commuter cyclists compared to car drivers. Furthermore, exposure to PM is linked to negative neurological effects, such as neuroinflammation and cognitive decline. We carried-out a cross-over experiment to examine the acute effect of exercise on serum BDNF, and the potential effect-modification by exposure to traffic-related air pollution. Thirty eight physically fit, non-asthmatic volunteers (mean age: 43, 26% women) performed two cycling trials, one near a major traffic road (Antwerp Ring, R1, up to 260,000 vehicles per day) and one in an air-filtered room. The air-filtered room was created by reducing fine particles as well as ultrafine particles (UFP). PM10, PM2.5 and UFP were measured. The duration (∼20min) and intensity of cycling were kept the same for each volunteer for both cycling trials. Serum BDNF concentrations were measured before and 30min after each cycling trial. Average concentrations of PM10 and PM2.5 were 64.9μg/m(3) and 24.6μg/m(3) in cycling near a major ring way, in contrast to 7.7μg/m(3) and 2.0μg/m(3) in the air-filtered room. Average concentrations of UFP were 28,180 particles/cm(3) along the road in contrast to 496 particles/cm(3) in the air-filtered room. As expected, exercise significantly increased serum BDNF concentration after cycling in the air-filtered room (+14.4%; p=0.02). In contrast, serum BDNF concentrations did not increase after cycling near the major traffic route (+0.5%; p

  5. Association of Polymorphisms in BDNF, MTHFR, and Genes Involved in the Dopaminergic Pathway with Memory in a Healthy Chinese Population

    Science.gov (United States)

    Yeh, Ting-Kuang; Hu, Chung-Yi; Yeh, Ting-Chi; Lin, Pei-Jung; Wu, Chung-Hsin; Lee, Po-Lei; Chang, Chun-Yen

    2012-01-01

    The contribution of genetic factors to the memory is widely acknowledged. Research suggests that these factors include genes involved in the dopaminergic pathway, as well as the genes for brain-derived neurotrophic factor (BDNF) and methylenetetrahydrofolate reductase (MTHFR). The activity of the products of these genes is affected by single…

  6. Bioenergetic programming of macrophages by the apolipoprotein A-I mimetic peptide 4F

    OpenAIRE

    Datta, Geeta; Kramer, Philip A.; Johnson, Michelle S.; Sawada, Hirotaka; Smythies, Lesley E.; Crossman, David K.; Chacko, Balu; Ballinger, Scott W.; Westbrook, David G.; Mayakonda, Palgunachari; Anantharamaiah, G.M.; Darley-Usmar, Victor M.; White, C. Roger

    2015-01-01

    The apoA-I (apolipoprotein A-I) mimetic peptide 4F favours the differentiation of human monocytes to an alternatively activated M2 phenotype. The goal of the present study was to test whether the 4F-mediated differentiation of MDMs (monocyte-derived macrophages) requires the induction of an oxidative metabolic programme. 4F treatment induced several genes in MDMs that play an important role in lipid metabolism, including PPARγ (peroxisome-proliferator-activated receptor γ) and CD36. Addition ...

  7. Aging Triggers a Repressive Chromatin State at Bdnf Promoters in Hippocampal Neurons

    Directory of Open Access Journals (Sweden)

    Ernest Palomer

    2016-09-01

    Full Text Available Cognitive capacities decline with age, an event accompanied by the altered transcription of synaptic plasticity genes. Here, we show that the transcriptional induction of Bdnf by a mnemonic stimulus is impaired in aged hippocampal neurons. Mechanistically, this defect is due to reduced NMDA receptor (NMDAR-mediated activation of CaMKII. Decreased NMDAR signaling prevents changes associated with activation at specific Bdnf promoters, including displacement of histone deacetylase 4, recruitment of the histone acetyltransferase CBP, increased H3K27 acetylation, and reduced H3K27 trimethylation. The decrease in NMDA-CaMKII signaling arises from constitutive reduction of synaptic cholesterol that occurs with normal aging. Increasing the levels of neuronal cholesterol in aged neurons in vitro, ex vivo, and in vivo restored NMDA-induced Bdnf expression and chromatin remodeling. Furthermore, pharmacological prevention of age-associated cholesterol reduction rescued signaling and cognitive deficits of aged mice. Thus, reducing hippocampal cholesterol loss may represent a therapeutic approach to reverse cognitive decline during aging.

  8. Cerebral 5-HT2A receptor and serotonin transporter binding in humans are not affected by the val66met BDNF polymorphism status or blood BDNF levels

    DEFF Research Database (Denmark)

    Klein, Anders Bue; Trajkovska, Viktorija; Erritzoe, David;

    2010-01-01

    Recent studies have proposed an interrelation between the brain-derived neurotrophic factor (BDNF) val66met polymorphism and the serotonin system. In this study, we investigated whether the BDNF val66met polymorphism or blood BDNF levels are associated with cerebral 5-hydroxytryptamine 2A (5-HT(2...

  9. Copper Complexes of Nicotinic-Aromatic Carboxylic Acids as Superoxide Dismutase Mimetics

    Directory of Open Access Journals (Sweden)

    Virapong Prachayasittikul

    2008-12-01

    Full Text Available Nicotinic acid (also known as vitamin B3 is a dietary element essential for physiological and antihyperlipidemic functions. This study reports the synthesis of novel mixed ligand complexes of copper with nicotinic and other select carboxylic acids (phthalic, salicylic and anthranilic acids. The tested copper complexes exhibited superoxide dismutase (SOD mimetic activity and antimicrobial activity against Bacillus subtilis ATCC 6633, with a minimum inhibition concentration of 256 μg/mL. Copper complex of nicotinic-phthalic acids (CuNA/Ph was the most potent with a SOD mimetic activity of IC50 34.42 μM. The SOD activities were observed to correlate well with the theoretical parameters as calculated using density functional theory (DFT at the B3LYP/LANL2DZ level of theory. Interestingly, the SOD activity of the copper complex CuNA/Ph was positively correlated with the electron affinity (EA value. The two quantum chemical parameters, highest occupied molecular orbital (HOMO and lowest unoccupied molecular orbital (LUMO, were shown to be appropriate for understanding the mechanism of the metal complexes as their calculated energies show good correlation with the SOD activity. Moreover, copper complex with the highest SOD activity were shown to possess the lowest HOMO energy. These findings demonstrate a great potential for the development of value-added metallovitamin-based therapeutics.

  10. Static spherically symmetric solutions in mimetic gravity: rotation curves & wormholes

    CERN Document Server

    Myrzakulov, Ratbay; Vagnozzi, Sunny; Zerbini, Sergio

    2015-01-01

    In this work, we analyse static spherically symmetric solutions in the framework of mimetic gravity, an extension of general relativity where the conformal degree of freedom of gravity is isolated in a covariant fashion. Here we extend previous works by considering in addition a potential for the mimetic field. An appropriate choice of such potential allows for the reconstruction of a number of interesting cosmological and astrophysical scenarios. We explicitly show how to reconstruct such a potential for a general static spherically symmetric space-time. A number of applications and scenarios are then explored, among which traversable wormholes. Finally, we analytically reconstruct potentials which leads to solutions to the equations of motion featuring polynomial corrections to the Schwarzschild spacetime. Accurate choices for such corrections could provide an explanation for the inferred flat rotation curves of spiral galaxies within the mimetic gravity framework, without the need for particle dark matter.

  11. Cholesterol overload induces apoptosis in SH-SY5Y human neuroblastoma cells through the up regulation of flotillin-2 in the lipid raft and the activation of BDNF/Trkb signaling.

    Science.gov (United States)

    Huang, Yen-Ning; Lin, Ching-I; Liao, Hsiang; Liu, Chin-Yu; Chen, Yue-Hua; Chiu, Wan-Chun; Lin, Shyh-Hsiang

    2016-07-22

    Epidemiological investigations have shown that Alzheimer's disease (AD) is one of the most common neurodegenerative diseases. It has been indicated that the cholesterol concentration in the brain of AD patients is higher than that in normal people. In this study, we investigated the effects of cholesterol concentrations, 0, as the control, 3.125, 12.5, and 25μM, on cholesterol metabolism, neuron survival, AD-related protein expressions, and cell morphology and apoptosis using SH-SY5Y human neuroblastoma cells. We observed that expressions of cholesterol hydroxylase (Cyp46), flotillin-2 (a marker of lipid raft content), and truncated tyrosine kinase B (TrkBtc) increased, while expressions of brain-derived neurotrophic factor (BDNF) and full-length TrkB (TrkBfl) decreased as the concentration of cholesterol loading increased. Down-regulation of the PI3K-Akt-glycogen synthase kinase (GSK)-3β cascade and cell apoptosis were also observed at higher concentrations of cholesterol, along with elevated levels of β-amyloid (Aβ), β-secretase (BACE), and reactive oxygen species (ROS). In conclusion, we found that cholesterol overload in neuronal cells imbalanced the cholesterol homeostasis and increased the protein expressions causing cell apoptosis, which illustrates the neurodegenerative pathology of abnormally elevated cholesterol concentrations found in AD patients.

  12. Social defeat during adolescence and adulthood differentially induce BDNF-regulated immediate early genes

    Directory of Open Access Journals (Sweden)

    Caroline M. Coppens

    2011-11-01

    Full Text Available Stressful life events generally enhance the vulnerability for the development of human psychopathologies such as anxiety disorders and depression. The incidence rates of adult mental disorders steeply rises during adolescence in parallel with a structural and functional reorganization of the neural circuitry underlying stress reactivity. However, the mechanisms underlying susceptibility to stress and manifestation of mental disorders during adolescence are little understood. We hypothesized that heightened sensitivity to stress during adolescence reflects age-dependent differences in the expression of activity-dependent genes involved in synaptic plasticity. Therefore, we compared the effect of social stress during adolescence with social stress in adulthood on the expression of a panel of genes linked to induction of long-term potentiation (LTP and brain-derived neurotrophic factor (BDNF signaling. We show that social defeat during adolescence and adulthood differentially regulates expression of the immediate early genes BDNF, Arc, Carp, and Tieg1, as measured by qPCR in tissue lysates from prefrontal cortex, nucleus accumbens, and hippocampus. In the hippocampus, mRNA levels for all four genes were robustly elevated following social defeat in adolescence, whereas none were induced by defeat in adulthood. The relationship to coping style was also examined using adult reactive and proactive coping rats. Gene expression levels of reactive and proactive animals were similar in the prefrontal cortex and hippocampus. However, a trend toward a differential expression of BDNF and Arc mRNA in the nucleus accumbens was detected. BDNF mRNA was increased in the nucleus accumbens of proactive defeated animals, whereas the expression level in reactive defeated animals was comparable to control animals. The results demonstrate striking differences in immediate early gene expression in response to social defeat in adolescent and adult rats.

  13. Expression and localisation of BDNF, NT4 and TrkB in proliferative vitreoretinopathy.

    Science.gov (United States)

    Ghazi-Nouri, Seyed M S; Ellis, James S; Moss, Stephen; Limb, G Astrid; Charteris, David G

    2008-05-01

    Exogenous brain derived neurotrophic factor (BDNF) is known to rescue ganglion cell death after optic nerve injury. Its mechanism of action is believed to be indirect via glial cells in the retina. In this study we investigated the changes in expression and localisation of BDNF, neurotrophin-4 (NT4) and their common receptor (TrkB) in retinectomy sections of patients with proliferative vitreoretinopathy (PVR). Nine full-thickness retinectomy specimens obtained at retinal reattachment surgery for PVR were fixed in 4% paraformaldehyde immediately after excision and compared to similarly processed normal donor retinas (4 eyes). Agarose-embedded sections (100 microm thick) were double labelled for immunohistochemistry by confocal microscopy, with antibodies against BDNF, NT4, TrkB, rod opsin, glial fibrillary acidic protein (GFAP), cellular retinaldehyde binding protein (CRALBP) and Brn3. This study demonstrates expression of NT4 by ganglion cells and shows expression of BDNF and NT4 in the outer photoreceptor segments is downregulated during PVR, whilst NT4 is markedly upregulated throughout the retina during this condition. The findings here suggest that NT4 may play a neural protective role during the development of PVR. It also shows that upregulation of NT4 in PVR is localised to Müller glial cells, indicating either over-expression of this factor by Müller cells or that Müller cells internalise NT4 for trafficking across the retina. TrkB expression was not observed in PVR retina. The observations that Müller glia demonstrate upregulation of NT4 suggests that retinal injury may lead to activation of this neurotrophin by Müller cells as part of their neuroprotective functions. PMID:18405896

  14. Effects of multiparity on recognition memory, monoaminergic neurotransmitters, and brain-derived neurotrophic factor (BDNF).

    Science.gov (United States)

    Macbeth, Abbe H; Scharfman, Helen E; Maclusky, Neil J; Gautreaux, Claris; Luine, Victoria N

    2008-06-01

    Recognition memory and anxiety were examined in nulliparous (NP: 0 litters) and multiparous (MP: 5-6 litters) middle-aged female rats (12 months old) to assess possible enduring effects of multiparity at least 3 months after the last litter was weaned. MP females performed significantly better than NP females on the non-spatial memory task, object recognition, and the spatial memory task, object placement. Anxiety as measured on the elevated plus maze did not differ between groups. Monoaminergic activity and levels were measured in prefrontal cortex, CA1 hippocampus, CA3 hippocampus, and olfactory bulb (OB). NP and MP females differed in monoamine concentrations in the OB only, with MP females having significantly greater concentrations of dopamine and metabolite DOPAC, norepinephrine and metabolite MHPG, and the serotonin metabolite 5-HIAA, as compared to NP females. These results indicate a long-term change in OB neurochemistry as a result of multiparity. Brain-derived neurotrophic factor (BDNF) was also measured in hippocampus (CA1, CA3, dentate gyrus) and septum. MP females had higher BDNF levels in both CA1 and septum; as these regions are implicated in memory performance, elevated BDNF may underlie the observed memory task differences. Thus, MP females (experiencing multiple bouts of pregnancy, birth, and pup rearing during the first year of life) displayed enhanced memory task performance but equal anxiety responses, as compared to NP females. These results are consistent with previous studies showing long-term changes in behavioral function in MP, as compared to NP, rats and suggest that alterations in monoamines and a neurotrophin, BDNF, may contribute to the observed behavioral changes.

  15. The BDNF Val66Met polymorphism: relation to familiar risk of affective disorder, BDNF levels and salivary cortisol

    DEFF Research Database (Denmark)

    Vinberg, Maj; Trajkovska, Viktorija; Bennike, Bente;

    2009-01-01

    BACKGROUND: Brain-derived neurotrophic factor (BDNF) and the hypothalamic-pituitary-adrenal (HPA) axis are considered to play an important role in the pathophysiology of affective disorders. The aim of the present study was to investigate whether the BDNF Val66Met polymorphism is associated...... with a familiar risk of affective disorder and whether these genotypes affect whole blood BDNF level and salivary cortisol. METHOD: In a high-risk study, healthy monozygotic and dizygotic twins with and without a co-twin (high- and low-risk twins, respectively) history of affective disorder were identified...... through nationwide registers. RESULTS: Familiar predisposition to unipolar and bipolar disorder was not associated with any specific genotype pattern of the BDNF Val66Met polymorphism, not in this sample of 124 val/val, 58 val/met and 8 met/met individuals. However, the combination of having a high...

  16. Aberrant hippocampal neurogenesis after limbic kindling: Relationship to BDNF and hippocampal-dependent memory.

    Science.gov (United States)

    Botterill, J J; Brymer, K J; Caruncho, H J; Kalynchuk, L E

    2015-06-01

    Seizures dramatically increase the number of adult generated neurons in the hippocampus. However, it is not known whether this effect depends on seizures that originate in specific brain regions or whether it is nonspecific to seizure activity regardless of origin. We used kindling of different brain sites to address this question. Rats received 99 kindling stimulations of the basolateral amygdala, dorsal hippocampus, or caudate nucleus over a 6-week period. After kindling, we counted the number of adult generated hippocampal neurons that were birth-dated with the proliferative marker bromodeoxyuridine (BrdU) to evaluate cell proliferation and survival under conditions of repeated seizures. Next, we counted the number of doublecortin immunoreactive (DCX-ir) cells and evaluated their dendritic complexity to determine if limbic and nonlimbic seizures have differential effects on neuronal maturation. We also quantified hippocampal brain-derived neurotrophin factor (BDNF) protein levels using an ELISA kit and assessed memory performance using a hippocampal-dependent fear conditioning paradigm. We found that limbic, but not nonlimbic, seizures dramatically increased hippocampal cell proliferation and the number of hilar-CA3 ectopic granule cells. Further, limbic kindling promoted dendritic outgrowth of DCX-ir cells and the number of DCX-ir cells containing basal dendrites. Limbic kindling also enhanced BDNF protein levels throughout the entire hippocampus and impaired the retrieval of fear memories. Collectively, our results suggest a relationship between limbic seizures, neurogenesis, BDNF protein, and cognition.

  17. The Effects of Acute Physical Exercise on Memory, Peripheral BDNF, and Cortisol in Young Adults

    Science.gov (United States)

    Röder, Brigitte; Schmidt-Kassow, Maren

    2016-01-01

    In animals, physical activity has been shown to induce functional and structural changes especially in the hippocampus and to improve memory, probably by upregulating the release of neurotrophic factors. In humans, results on the effect of acute exercise on memory are inconsistent so far. Therefore, the aim of the present study was to assess the effects of a single bout of physical exercise on memory consolidation and the underlying neuroendocrinological mechanisms in young adults. Participants encoded a list of German-Polish vocabulary before exercising for 30 minutes with either high intensity or low intensity or before a relaxing phase. Retention of the vocabulary was assessed 20 minutes after the intervention as well as 24 hours later. Serum BDNF and salivary cortisol were measured at baseline, after learning, and after the intervention. The high-intensity exercise group showed an increase in BDNF and cortisol after exercising compared to baseline. Exercise after learning did not enhance the absolute number of recalled words. Participants of the high-intensity exercise group, however, forgot less vocabulary than the relaxing group 24 hours after learning. There was no robust relationship between memory scores and the increase in BDNF and cortisol, respectively, suggesting that further parameters have to be taken into account to explain the effects of exercise on memory in humans. PMID:27437149

  18. The Effects of Acute Physical Exercise on Memory, Peripheral BDNF, and Cortisol in Young Adults

    Directory of Open Access Journals (Sweden)

    Kirsten Hötting

    2016-01-01

    Full Text Available In animals, physical activity has been shown to induce functional and structural changes especially in the hippocampus and to improve memory, probably by upregulating the release of neurotrophic factors. In humans, results on the effect of acute exercise on memory are inconsistent so far. Therefore, the aim of the present study was to assess the effects of a single bout of physical exercise on memory consolidation and the underlying neuroendocrinological mechanisms in young adults. Participants encoded a list of German-Polish vocabulary before exercising for 30 minutes with either high intensity or low intensity or before a relaxing phase. Retention of the vocabulary was assessed 20 minutes after the intervention as well as 24 hours later. Serum BDNF and salivary cortisol were measured at baseline, after learning, and after the intervention. The high-intensity exercise group showed an increase in BDNF and cortisol after exercising compared to baseline. Exercise after learning did not enhance the absolute number of recalled words. Participants of the high-intensity exercise group, however, forgot less vocabulary than the relaxing group 24 hours after learning. There was no robust relationship between memory scores and the increase in BDNF and cortisol, respectively, suggesting that further parameters have to be taken into account to explain the effects of exercise on memory in humans.

  19. Deep brain stimulation of the ventral striatum increases BDNF in the fear extinction circuit

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    Fabricio H Do-Monte

    2013-08-01

    Full Text Available Deep brain stimulation (DBS of the ventral capsule/ventral striatum (VC/VS reduces the symptoms of treatment-resistant obsessive compulsive disorder (OCD, and improves response to extinction-based therapies. We recently reported that DBS-like stimulation of a rat homologue of VC/VS, the dorsal-VS, reduced conditioned fear and enhanced extinction memory (Rodriguez-Romaguera et al, 2012. In contrast, DBS of the ventral-VS had the opposite effects. To examine possible mechanisms, we assessed the effects of VS DBS on the expression of the neural activity marker Fos and brain-derived neurotrophic factor (BDNF, a key mediator of extinction plasticity in prefrontal-amygdala circuits. Consistent with decreased fear expression, DBS of dorsal-VS increased Fos expression in prelimbic and infralimbic prefrontal cortices and in the lateral division of the central nucleus of amygdala, an area that inhibits amygdala output. Consistent with improved extinction memory, we found that DBS of dorsal-VS, but not ventral-VS, increased neuronal BDNF expression in prelimbic and infralimbic prefrontal cortices. These rodent findings are consistent with the idea that clinical DBS of VC/VS may augment fear extinction through an increase in BDNF expression.

  20. Deep brain stimulation of the ventral striatum increases BDNF in the fear extinction circuit.

    Science.gov (United States)

    Do-Monte, Fabricio H; Rodriguez-Romaguera, Jose; Rosas-Vidal, Luis E; Quirk, Gregory J

    2013-01-01

    Deep brain stimulation (DBS) of the ventral capsule/ventral striatum (VC/VS) reduces the symptoms of treatment-resistant obsessive compulsive disorder (OCD), and improves response to extinction-based therapies. We recently reported that DBS-like stimulation of a rat homologue of VC/VS, the dorsal-VS, reduced conditioned fear and enhanced extinction memory (Rodriguez-Romaguera et al., 2012). In contrast, DBS of the ventral-VS had the opposite effects. To examine possible mechanisms of these effects, we assessed the effects of VS DBS on the expression of the neural activity marker Fos and brain-derived neurotrophic factor (BDNF), a key mediator of extinction plasticity in prefrontal-amygdala circuits. Consistent with decreased fear expression, DBS of dorsal-VS increased Fos expression in prelimbic and infralimbic prefrontal cortices and in the lateral division of the central nucleus of amygdala, an area that inhibits amygdala output. Consistent with improved extinction memory, we found that DBS of dorsal-VS, but not ventral-VS, increased neuronal BDNF expression in prelimbic and infralimbic prefrontal cortices. These rodent findings are consistent with the idea that clinical DBS of VC/VS may augment fear extinction through an increase in BDNF expression. PMID:23964215

  1. Reactive Transformation and Increased BDNF Signaling by Hippocampal Astrocytes in Response to MK-801.

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    Wenjuan Yu

    Full Text Available MK-801, also known as dizocilpine, is a noncompetitive N-methyl-D-aspartic acid (NMDA receptor antagonist that induces schizophrenia-like symptoms. While astrocytes have been implicated in the pathophysiology of psychiatric disorders, including schizophrenia, astrocytic responses to MK-801 and their significance to schizotypic symptoms are unclear. Changes in the expression levels of glial fibrillary acid protein (GFAP, a marker of astrocyte activation in response to a variety of pathogenic stimuli, were examined in the hippocampus of rats treated with the repeated MK-801 injection (0.5 mg/10 ml/kg body weight for 6 days and in primary cultured hippocampal astrocytes incubated with MK-801 (5 or 20 μM for 24 h. Moreover, the expression levels of BDNF and its receptors TrkB and p75 were examined in MK-801-treated astrocyte cultures. MK-801 treatment enhanced GFAP expression in the rat hippocampus and also increased the levels of GFAP protein and mRNA in hippocampal astrocytes in vitro. Treatment of cultured hippocampal astrocytes with MK-801 enhanced protein and mRNA levels of BDNF, TrkB, and p75. Collectively, our results suggest that hippocampal astrocytes may contribute to the pathophysiology of schizophrenia symptoms associated with NMDA receptor hypofunction by reactive transformation and altered BDNF signaling.

  2. From Complex Natural Products to Simple Synthetic Mimetics by Computational De Novo Design.

    Science.gov (United States)

    Friedrich, Lukas; Rodrigues, Tiago; Neuhaus, Claudia S; Schneider, Petra; Schneider, Gisbert

    2016-06-01

    We present the computational de novo design of synthetically accessible chemical entities that mimic the complex sesquiterpene natural product (-)-Englerin A. We synthesized lead-like probes from commercially available building blocks and profiled them for activity against a computationally predicted panel of macromolecular targets. Both the design template (-)-Englerin A and its low-molecular weight mimetics presented nanomolar binding affinities and antagonized the transient receptor potential calcium channel TRPM8 in a cell-based assay, without showing target promiscuity or frequent-hitter properties. This proof-of-concept study outlines an expeditious solution to obtaining natural-product-inspired chemical matter with desirable properties. PMID:27111835

  3. Effects of brain-derived neurotrophic factor (BDNF) and electrical stimulation on survival and function of cochlear spiral ganglion neurons in deafened, developing cats.

    Science.gov (United States)

    Leake, Patricia A; Stakhovskaya, Olga; Hetherington, Alexander; Rebscher, Stephen J; Bonham, Ben

    2013-04-01

    Both neurotrophic support and neural activity are required for normal postnatal development and survival of cochlear spiral ganglion (SG) neurons. Previous studies in neonatally deafened cats demonstrated that electrical stimulation (ES) from a cochlear implant can promote improved SG survival but does not completely prevent progressive neural degeneration. Neurotrophic agents combined with an implant may further improve neural survival. Short-term studies in rodents have shown that brain-derived neurotrophic factor (BDNF) promotes SG survival after deafness and may be additive to trophic effects of stimulation. Our recent study in neonatally deafened cats provided the first evidence of BDNF neurotrophic effects in the developing auditory system over a prolonged duration Leake et al. (J Comp Neurol 519:1526-1545, 2011). Ten weeks of intracochlear BDNF infusion starting at 4 weeks of age elicited significant improvement in SG survival and larger soma size compared to contralateral. In the present study, the same deafening and BDNF infusion procedures were combined with several months of ES from an implant. After combined BDNF + ES, a highly significant increase in SG numerical density (>50 % improvement re: contralateral) was observed, which was significantly greater than the neurotrophic effect seen with ES-only over comparable durations. Combined BDNF + ES also resulted in a higher density of myelinated radial nerve fibers within the osseous spiral lamina. However, substantial ectopic and disorganized sprouting of these fibers into the scala tympani also occurred, which may be deleterious to implant function. EABR thresholds improved (re: initial thresholds at time of implantation) on the chronically stimulated channels of the implant. Terminal electrophysiological studies recording in the inferior colliculus (IC) revealed that the basic cochleotopic organization was intact in the midbrain in all studied groups. In deafened controls or after ES-only, lower IC

  4. Are variations in whole blood BDNF level associated with the BDNF Val66Met polymorphism in patients with first episode depression?

    DEFF Research Database (Denmark)

    Vinberg, Maj; Bukh, Jens Otto Drachmann; Bennike, Bente;

    2013-01-01

    Brain derived neurotrophic factor (BDNF) seems to play an important role in the pathophysiology of affective disorders. The current study investigated whether blood level BDNF is correlated with the severity of depressive symptoms and recent (six months prior to onset of depression) experience......). Symptomatology was rated using Hamilton Rating Scale for Depression (HAMD-17) and Becks Depression Inventory (BDI 21). No differences in whole blood BDNF was seen in relation to the BDNF Val66Met polymorphism and no significant correlations between whole blood BDNF and HAMD-17 or BDI 21 scores were found....... No significant associations between the experiences of SLE before onset of depression and BDNF level were observed. Finally, peripheral BDNF differentiated between patients and healthy control persons. In the current sample of first episode depressed patients, the Val66Met polymorphism was not associated...

  5. Enriched Environment Attenuates Surgery-Induced Impairment of Learning, Memory, and Neurogenesis Possibly by Preserving BDNF Expression.

    Science.gov (United States)

    Fan, Dan; Li, Jun; Zheng, Bin; Hua, Lei; Zuo, Zhiyi

    2016-01-01

    Postoperative cognitive dysfunction (POCD) is a significant clinical syndrome. Neurogenesis contributes to cognition. It is known that enriched environment (EE) enhances neurogenesis. We determined whether EE attenuated surgery-induced cognitive impairment and whether growth factors and neurogenesis played a role in the EE effect. Eight-week-old C57BL/6J mice were subjected to carotid artery exposure. Their learning and memory were assessed by Barnes maze, and fear conditioning started 2 weeks after the surgery. Growth factor expression and cell genesis were determined at various times after the surgery. Surgery increased the time for the mice to identify the target hole in the Barnes maze and reduced context-related freezing behavior. Surgery also reduced the expression of brain-derived neurotrophic factor (BDNF) and neurogenesis in the hippocampus. These effects were attenuated by EE. EE also attenuated surgery-induced reduction of phosphorylated/activated tropomyosin-related kinase B (TrkB) and extracellular signal-regulated kinases (ERK), components of BDNF signaling pathway. ANA-12, a selective TrkB antagonist, blocked the effects of EE on cognition, phosphorylation of TrkB and ERK, and neurogenesis. These results provide initial evidence that surgery reduces BDNF expression and neurogenesis in the hippocampus. Our results suggest that EE reduces surgery-induced impairment of learning, memory, and neurogenesis by preserving BDNF expression.

  6. Curcumin Improves Amyloid β-Peptide (1-42 Induced Spatial Memory Deficits through BDNF-ERK Signaling Pathway.

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    Lu Zhang

    Full Text Available Curcumin, the most active component of turmeric, has various beneficial properties, such as antioxidant, anti-inflammatory, and antitumor effects. Previous studies have suggested that curcumin reduces the levels of amyloid and oxidized proteins and prevents memory deficits and thus is beneficial to patients with Alzheimer's disease (AD. However, the molecular mechanisms underlying curcumin's effect on cognitive functions are not well-understood. In the present study, we examined the working memory and spatial reference memory in rats that received a ventricular injection of amyloid-β1-42 (Aβ1-42, representing a rodent model of Alzheimer's disease (AD. The rats treated with Aβ1-42 exhibited obvious cognitive deficits in behavioral tasks. Chronic (seven consecutive days, once per day but not acute (once a day curcumin treatments (50, 100, and 200 mg/kg improved the cognitive functions in a dose-dependent manner. In addition, the beneficial effect of curcumin is accompanied by increased BDNF levels and elevated levels of phosphorylated ERK in the hippocampus. Furthermore, the cognition enhancement effect of curcumin could be mimicked by the overexpression of BDNF in the hippocampus and blocked by either bilateral hippocampal injections with lentiviruses that express BDNF shRNA or a microinjection of ERK inhibitor. These findings suggest that chronic curcumin ameliorates AD-related cognitive deficits and that upregulated BDNF-ERK signaling in the hippocampus may underlie the cognitive improvement produced by curcumin.

  7. Sera from children with autism induce autistic features which can be rescued with a CNTF small peptide mimetic in rats.

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    Syed Faraz Kazim

    Full Text Available Autism is a neurodevelopmental disorder characterized clinically by impairments in social interaction and verbal and non-verbal communication skills as well as restricted interests and repetitive behavior. It has been hypothesized that altered brain environment including an imbalance in neurotrophic support during early development contributes to the pathophysiology of autism. Here we report that sera from children with autism which exhibited abnormal levels of various neurotrophic factors induced cell death and oxidative stress in mouse primary cultured cortical neurons. The effects of sera from autistic children were rescued by pre-treatment with a ciliary neurotrophic factor (CNTF small peptide mimetic, Peptide 6 (P6, which was previously shown to exert its neuroprotective effect by modulating CNTF/JAK/STAT pathway and LIF signaling and by enhancing brain derived neurotrophic factor (BDNF expression. Similar neurotoxic effects and neuroinflammation were observed in young Wistar rats injected intracerebroventricularly with autism sera within hours after birth. The autism sera injected rats demonstrated developmental delay and deficits in social communication, interaction, and novelty. Both the neurobiological changes and the behavioral autistic phenotype were ameliorated by P6 treatment. These findings implicate the involvement of neurotrophic imbalance during early brain development in the pathophysiology of autism and a proof of principle of P6 as a potential therapeutic strategy for autism.

  8. Bio-Mimetic Sensors Based on Molecularly Imprinted Membranes

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    Catia Algieri

    2014-07-01

    Full Text Available An important challenge for scientific research is the production of artificial systems able to mimic the recognition mechanisms occurring at the molecular level in living systems. A valid contribution in this direction resulted from the development of molecular imprinting. By means of this technology, selective molecular recognition sites are introduced in a polymer, thus conferring it bio-mimetic properties. The potential applications of these systems include affinity separations, medical diagnostics, drug delivery, catalysis, etc. Recently, bio-sensing systems using molecularly imprinted membranes, a special form of imprinted polymers, have received the attention of scientists in various fields. In these systems imprinted membranes are used as bio-mimetic recognition elements which are integrated with a transducer component. The direct and rapid determination of an interaction between the recognition element and the target analyte (template was an encouraging factor for the development of such systems as alternatives to traditional bio-assay methods. Due to their high stability, sensitivity and specificity, bio-mimetic sensors-based membranes are used for environmental, food, and clinical uses. This review deals with the development of molecularly imprinted polymers and their different preparation methods. Referring to the last decades, the application of these membranes as bio-mimetic sensor devices will be also reported.

  9. Combinatorial solid-phase synthesis of hapalosin mimetics

    DEFF Research Database (Denmark)

    Olsen, Jacob A.; Jensen, Knud J.; Nielsen, John

    2000-01-01

    The solid-phase synthesis of a small library of mimetics of the cyclic depsipeptide hapalosin is described. 3-Amino-4-hydroxy-5-nitrobenzoic acid was anchored through the anilino moiety to a backbone amide linker (BAL) handle support. Using chemoselective reactions and without the need for...

  10. Dark energy oscillations in mimetic F (R ) gravity

    Science.gov (United States)

    Odintsov, S. D.; Oikonomou, V. K.

    2016-08-01

    In this paper we address the problem of dark energy oscillations in the context of mimetic F (R ) gravity with potential. The issue of dark energy oscillations can be a problem in some models of ordinary F (R ) gravity, and a remedy that can make the oscillations milder is to introduce additional modifications in the functional form of the F (R ) gravity. As we demonstrate, the power-law modifications are not necessary in the mimetic F (R ) case, and by appropriately choosing the mimetic potential and the Lagrange multiplier, it is possible to make the oscillations almost vanish at the end of the matter domination era and during the late-time acceleration era. We examine the behavior of the dark energy equation of state parameter and of the total effective equation of state parameter as functions of the redshift, and we compare the resulting picture with the ordinary F (R ) gravity case. As we also show that the present day values of the dark energy equation of state parameter and of the total effective equation of state parameter are in better agreement with the observational data, in comparison to the ordinary F (R ) gravity case. Finally, we study the evolution of the growth factor as a function of the redshift for all the mimetic models we use.

  11. Chronic stress-induced memory deficits are reversed by regular exercise via AMPK-mediated BDNF induction.

    Science.gov (United States)

    Kim, D-M; Leem, Y-H

    2016-06-01

    Chronic stress has a detrimental effect on neurological insults, psychiatric deficits, and cognitive impairment. In the current study, chronic stress was shown to impair learning and memory functions, in addition to reducing in hippocampal Adenosine monophosphate-activated protein kinase (AMPK) activity. Similar reductions were also observed for brain-derived neurotrophic factor (BDNF), synaptophysin, and post-synaptic density-95 (PSD-95) levels, all of which was counter-regulated by a regime of regular and prolonged exercise. A 21-day restraint stress regimen (6 h/day) produced learning and memory deficits, including reduced alternation in the Y-maze and decreased memory retention in the water maze test. These effects were reversed post-administration by a 3-week regime of treadmill running (19 m/min, 1 h/day, 6 days/week). In hippocampal primary culture, phosphorylated-AMPK (phospho-AMPK) and BDNF levels were enhanced in a dose-dependent manner by 5-amimoimidazole-4-carboxamide riboside (AICAR) treatment, and AICAR-treated increase was blocked by Compound C. A 7-day period of AICAR intraperitoneal injections enhanced alternation in the Y-maze test and reduced escape latency in water maze test, along with enhanced phospho-AMPK and BDNF levels in the hippocampus. The intraperitoneal injection of Compound C every 4 days during exercise intervention diminished exercise-induced enhancement of memory improvement during the water maze test in chronically stressed mice. Also, chronic stress reduced hippocampal neurogenesis (lower Ki-67- and doublecortin-positive cells) and mRNA levels of BDNF, synaptophysin, and PSD-95. Our results suggest that regular and prolonged exercise can alleviate chronic stress-induced hippocampal-dependent memory deficits. Hippocampal AMPK-engaged BDNF induction is at least in part required for exercise-induced protection against chronic stress. PMID:26975895

  12. Involuntary, Forced and Voluntary Exercises Equally Attenuate Neurocognitive Deficits in Vascular Dementia by the BDNF-pCREB Mediated Pathway.

    Science.gov (United States)

    Lin, Yangyang; Lu, Xiao; Dong, Juntao; He, Xiaokuo; Yan, Tiebin; Liang, Huiying; Sui, Minghong; Zheng, Xiuyuan; Liu, Huihua; Zhao, Jingpu; Lu, Xinxin

    2015-09-01

    A rat model of vascular dementia was used to compare the effects of involuntary exercise induced by functional electrical stimulation (FES), forced exercise and voluntary exercise on the recovery of cognitive function recovery and its underlying mechanisms. In an involuntary exercise (I-EX) group, FES was used to induce involuntary gait-like running on ladder at 12 m/min. A forced exercise group (F-EX) and a voluntary exercise group (V-EX) exercised by wheel running. The Barnes maze was used for behavioral assessment. Brain-derived neurotrophic factor (BDNF), phosphorylated extracellular signal-regulated kinase 1 and 2 (ERK1/2) and cAMP response element binding protein (CREB) positive cells in hippocampal CA1, CA2/3 and dentate gyrus (DG) regions were evaluated using immunohistochemical methods. Western blotting was used to assess the levels of BDNF, phosphorylated protein kinase B (Akt), tropomyosin receptor kinase B (TrkB), mitogen-activated protein kinase 1 and 2 (MEK1/2), ERK1/2 and CREB in BDNF-pCREB signaling in the hippocampus and prefrontal cortex. Involuntary, forced and voluntary exercises were all found to reverse the cognitive deficits of vascular dementia with about equal effectiveness. The number of BDNF, pCREB and pERK1/2 immunopositive cells was significantly increased in the hippocampal CA1, CA2/3 and DG regions in all three exercise groups. In addition, involuntary exercise activated BDNF and the phosphorylation of Akt, TrkB, MEK1/2, ERK1/2 and CREB in the hippocampus and prefrontal cortex equally as well as voluntary or forced exercise. These results suggest that involuntary exercise induced by FES may be as beneficial for alleviating cognitive deficits after cerebral ischemia. PMID:26240057

  13. Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism affects sympathetic tone in a gender-specific way.

    Science.gov (United States)

    Chang, Chuan-Chia; Chang, Hsin-An; Chen, Tien-Yu; Fang, Wen-Hui; Huang, San-Yuan

    2014-09-01

    The Val/Val genotype of the brain-derived neurotrophic factor (BDNF) polymorphism (Val66Met) has been reported to affect human anxiety-related phenotypes. Substantial research has demonstrated that anxiety is associated with sympathetic activation, while sex steroid hormones have been shown to exert differential actions in regulating BDNF expression. Thus, we examined whether the BDNF variant modulates autonomic function in a gender-dependent manner. From 708 adults initially screened for medical and psychiatric illnesses, a final cohort of 583 drug-free healthy Han Chinese (355 males, 228 females; age 34.43±8.42 years) was recruited for BDNF genotyping (Val/Val: 136, 23.3%, Val/Met: 294, 50.4%, and Met/Met: 153, 26.2%). Time- and frequency-domain analyses of heart rate variability (HRV) were used to assess autonomic outflow to the heart. Significant genotype-by-gender interaction effects were found on HRV indices. Even after adjusting for possible confounders, male participants bearing the Val/Val genotype had significant increases in low frequency (LF), LF% and LF/high frequency (HF) ratio, indicating altered sympathovagal balance with increased sympathetic modulation, compared to male Met/Met homozygotes. Females, however, showed an opposite but non-significant pattern. These results suggest that the studied BDNF polymorphism is associated with sympathetic control in a gender-specific way. The findings here support the view that male subjects with the Val/Val genotype have increased risk of anxiety by association with sympathetic activation.

  14. Serum BDNF correlates with connectivity in the (pre)motor hub in the aging human brain--a resting-state fMRI pilot study.

    Science.gov (United States)

    Mueller, Karsten; Arelin, Katrin; Möller, Harald E; Sacher, Julia; Kratzsch, Jürgen; Luck, Tobias; Riedel-Heller, Steffi; Villringer, Arno; Schroeter, Matthias L

    2016-02-01

    Brain-derived neurotrophic factor (BDNF) has been discussed to be involved in plasticity processes in the human brain, in particular during aging. Recently, aging and its (neurodegenerative) diseases have increasingly been conceptualized as disconnection syndromes. Here, connectivity changes in neural networks (the connectome) are suggested to be the most relevant and characteristic features for such processes or diseases. To further elucidate the impact of aging on neural networks, we investigated the interaction between plasticity processes, brain connectivity, and healthy aging by measuring levels of serum BDNF and resting-state fMRI data in 25 young (mean age 24.8 ± 2.7 (SD) years) and 23 old healthy participants (mean age, 68.6 ± 4.1 years). To identify neural hubs most essentially related to serum BDNF, we applied graph theory approaches, namely the new data-driven and parameter-free approach eigenvector centrality (EC) mapping. The analysis revealed a positive correlation between serum BDNF and EC in the premotor and motor cortex in older participants in contrast to young volunteers, where we did not detect any association. This positive relationship between serum BDNF and EC appears to be specific for older adults. Our results might indicate that the amount of physical activity and learning capacities, leading to higher BDNF levels, increases brain connectivity in (pre)motor areas in healthy aging in agreement with rodent animal studies. Pilot results have to be replicated in a larger sample including behavioral data to disentangle the cause for the relationship between BDNF levels and connectivity. PMID:26827656

  15. Antidepressant drugs transactivate TrkB neurotrophin receptors in the adult rodent brain independently of BDNF and monoamine transporter blockade.

    Directory of Open Access Journals (Sweden)

    Tomi Rantamäki

    Full Text Available BACKGROUND: Antidepressant drugs (ADs have been shown to activate BDNF (brain-derived neurotrophic factor receptor TrkB in the rodent brain but the mechanism underlying this phenomenon remains unclear. ADs act as monoamine reuptake inhibitors and after prolonged treatments regulate brain bdnf mRNA levels indicating that monoamine-BDNF signaling regulate AD-induced TrkB activation in vivo. However, recent findings demonstrate that Trk receptors can be transactivated independently of their neurotrophin ligands. METHODOLOGY: In this study we examined the role of BDNF, TrkB kinase activity and monoamine reuptake in the AD-induced TrkB activation in vivo and in vitro by employing several transgenic mouse models, cultured neurons and TrkB-expressing cell lines. PRINCIPAL FINDINGS: Using a chemical-genetic TrkB(F616A mutant and TrkB overexpressing mice, we demonstrate that ADs specifically activate both the maturely and immaturely glycosylated forms of TrkB receptors in the brain in a TrkB kinase dependent manner. However, the tricyclic AD imipramine readily induced the phosphorylation of TrkB receptors in conditional bdnf⁻/⁻ knock-out mice (132.4±8.5% of control; P = 0.01, indicating that BDNF is not required for the TrkB activation. Moreover, using serotonin transporter (SERT deficient mice and chemical lesions of monoaminergic neurons we show that neither a functional SERT nor monoamines are required for the TrkB phosphorylation response induced by the serotonin selective reuptake inhibitors fluoxetine or citalopram, or norepinephrine selective reuptake inhibitor reboxetine. However, neither ADs nor monoamine transmitters activated TrkB in cultured neurons or cell lines expressing TrkB receptors, arguing that ADs do not directly bind to TrkB. CONCLUSIONS: The present findings suggest that ADs transactivate brain TrkB receptors independently of BDNF and monoamine reuptake blockade and emphasize the need of an intact tissue context for the

  16. Elevation of BDNF exon I-specific transcripts in the frontal cortex and midbrain of rat during spontaneous morphine withdrawal is accompanied by enhanced pCreb1 occupancy at the corresponding promoter.

    Science.gov (United States)

    Peregud, Danil I; Panchenko, Leonid F; Gulyaeva, Natalia V

    2015-01-01

    Brain-derived neurotrophic factor (BDNF) is believed to play a crucial role in the mechanisms underlying opiate dependence; however, little is known about specific features and mechanisms regulating its expression in the brain under these conditions. The aim of this study was to investigate the effects of acute morphine intoxication and withdrawal from chronic intoxication on expression of BDNF exon I-, II-, IV-, VI- and IX-containing transcripts in the rat frontal cortex and midbrain. We also have studied whether alterations of BDNF exon-specific transcripts are accompanied by changes in association of well-known transcriptional regulators of BDNF gene-phosphorylated (active form) cAMP response element binding protein (pCreb1) and methyl-CpG binding protein 2 (MeCP2) with corresponding regulatory regions of the BDNF gene. Acute morphine intoxication did not affect levels of BDNF exons in brain regions, while spontaneous morphine withdrawal in dependent rats was accompanied by an elevation of the BDNF exon I-containing mRNAs both in the frontal cortex and midbrain. During spontaneous morphine withdrawal, increased associations of pCreb1 were found with promoter of exon I in the frontal cortex and promoters of exon I, IV and VI in the midbrain. The association of MeCP2 with BDNF promoters during spontaneous morphine withdrawal did not change. Thus, BDNF exon-specific transcripts are differentially expressed in brain regions during spontaneous morphine withdrawal in dependent rats and pCreb1 may be at least partially responsible for these alterations.

  17. The SMAC mimetic, LCL-161, reduces survival in aggressive MYC-driven lymphoma while promoting susceptibility to endotoxic shock.

    Science.gov (United States)

    West, A C; Martin, B P; Andrews, D A; Hogg, S J; Banerjee, A; Grigoriadis, G; Johnstone, R W; Shortt, J

    2016-01-01

    Inhibitor of apoptosis proteins (IAPs) antagonize caspase activation and regulate death receptor signaling cascades. LCL-161 is a small molecule second mitochondrial activator of caspase (SMAC) mimetic, which both disengages IAPs from caspases and induces proteasomal degradation of cIAP-1 and -2, resulting in altered signaling through the NFκB pathway, enhanced TNF production and sensitization to apoptosis mediated by the extrinsic pathway. SMAC mimetics are undergoing clinical evaluation in a range of hematological malignancies. Burkitt-like lymphomas are hallmarked by a low apoptotic threshold, conveying sensitivity to a range of apoptosis-inducing stimuli. While evaluating LCL-161 in the Eμ-Myc model of aggressive Burkitt-like lymphoma, we noted unexpected resistance to apoptosis induction despite 'on-target' IAP degradation and NFκB activation. Moreover, LCL-161 treatment of lymphoma-bearing mice resulted in apparent disease acceleration concurrent to augmented inflammatory cytokine-release in the same animals. Indiscriminate exposure of lymphoma patients to SMAC mimetics may therefore be detrimental due to both unanticipated prolymphoma effects and increased susceptibility to endotoxic shock. PMID:27043662

  18. Elaborate Mimetic Vocal Displays by Female Superb Lyrebirds

    Directory of Open Access Journals (Sweden)

    Anastasia H Dalziell

    2016-04-01

    Full Text Available Some of the most striking vocalizations in birds are made by males that incorporate vocal mimicry in their sexual displays. Mimetic vocalization in females is largely undescribed, but it is unclear whether this is because of a lack of selection for vocal mimicry in females, or whether the phenomenon has simply been overlooked. These issues are thrown into sharp relief in the superb lyrebird, Menura novaehollandiae, a basal oscine passerine with a lek-like mating system and female uniparental care. The spectacular mimetic song display produced by courting male lyrebirds is a textbook example of a sexually selected trait, but the vocalizations of female lyrebirds are largely unknown. Here, we provide the first analysis of the structure and context of the vocalizations of female lyrebirds. Female lyrebirds were completely silent during courtship; however, females regularly produced sophisticated vocal displays incorporating both lyrebird-specific vocalizations and imitations of sounds within their environment. The structure of female vocalizations varied significantly with context. While foraging, females mostly produced a complex lyrebird-specific song, whereas they gave lyrebird-specific alarm calls most often during nest defense. Within their vocal displays females also included a variety of mimetic vocalizations, including imitations of the calls of dangerous predators, and of alarm calls and song of harmless heterospecifics. Females gave more mimetic vocalizations during nest defense than while foraging, and the types of sounds they imitated varied between these contexts, suggesting that mimetic vocalizations have more than one function. These results are inconsistent with previous portrayals of vocalizations by female lyrebirds as rare, functionless by-products of sexual selection on males. Instead, our results support the hypotheses that complex female vocalizations play a role in nest defense and mediate female-female competition for

  19. The Brain-Derived Neurotrophic Factor Val66Met Polymorphism Moderates an Effect of Physical Activity on Working Memory Performance

    OpenAIRE

    Erickson, Kirk I.; Banducci, Sarah E.; Weinstein, Andrea M.; MacDonald, Angus W.; Ferrell, Robert E.; Halder, Indrani; Flory, Janine D.; Manuck, Stephen B.

    2013-01-01

    Physical activity enhances cognitive performance, yet individual variability in its effectiveness limits its widespread therapeutic application. Genetic differences might be one source of this variation. For example, carriers of the methionine-specifying (Met) allele of the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism have reduced secretion of BDNF and poorer memory, yet physical activity increases BDNF levels. To determine whether the BDNF polymorphism moderated an associat...

  20. BDNF gene effects on brain circuitry replicated in 455 twins.

    Science.gov (United States)

    Chiang, Ming-Chang; Barysheva, Marina; Toga, Arthur W; Medland, Sarah E; Hansell, Narelle K; James, Michael R; McMahon, Katie L; de Zubicaray, Greig I; Martin, Nicholas G; Wright, Margaret J; Thompson, Paul M

    2011-03-15

    Brain-derived neurotrophic factor (BDNF) plays a key role in learning and memory, but its effects on the fiber architecture of the living brain are unknown. We genotyped 455 healthy adult twins and their non-twin siblings (188 males/267 females; age: 23.7±2.1 years, mean±SD) and scanned them with high angular resolution diffusion tensor imaging (DTI), to assess how the BDNF Val66Met polymorphism affects white matter microstructure. By applying genetic association analysis to every 3D point in the brain images, we found that the Val-BDNF genetic variant was associated with lower white matter integrity in the splenium of the corpus callosum, left optic radiation, inferior fronto-occipital fasciculus, and superior corona radiata. Normal BDNF variation influenced the association between subjects' performance intellectual ability (as measured by Object Assembly subtest) and fiber integrity (as measured by fractional anisotropy; FA) in the callosal splenium, and pons. BDNF gene may affect the intellectual performance by modulating the white matter development. This combination of genetic association analysis and large-scale diffusion imaging directly relates a specific gene to the fiber microstructure of the living brain and to human intelligence. PMID:21195196

  1. The action of mimetic peptides on connexins protects fibroblasts from the negative effects of ischemia reperfusion

    Science.gov (United States)

    Glass, Beverley J.; Hu, Rebecca G.; Phillips, Anthony R. J.; Becker, David L.

    2015-01-01

    ABSTRACT Connexins have been proposed as a target for therapeutic treatment of a variety of conditions. The main approaches have been by antisense or small peptides specific against connexins. Some of these peptides enhance communication while others interfere with connexin binding partners or bind to the intracellular and extracellular loops of connexins. Here, we explored the mechanism of action of a connexin mimetic peptide by evaluating its effect on gap junction channels, connexin protein levels and hemichannel activity in fibroblast cells under normal conditions and following ischemia reperfusion injury which elevates Cx43 levels, increases hemichannel activity and causes cell death. Our results showed that the effects of the mimetic peptide were concentration-dependent. High concentrations (100-300 μM) significantly reduced Cx43 protein levels and GJIC within 2 h, while these effects did not appear until 6 h when using lower concentrations (10-30 μM). Cell death can be reduced when hemichannel opening and GJIC were minimised. PMID:26471768

  2. The action of mimetic peptides on connexins protects fibroblasts from the negative effects of ischemia reperfusion

    Directory of Open Access Journals (Sweden)

    Beverley J. Glass

    2015-11-01

    Full Text Available Connexins have been proposed as a target for therapeutic treatment of a variety of conditions. The main approaches have been by antisense or small peptides specific against connexins. Some of these peptides enhance communication while others interfere with connexin binding partners or bind to the intracellular and extracellular loops of connexins. Here, we explored the mechanism of action of a connexin mimetic peptide by evaluating its effect on gap junction channels, connexin protein levels and hemichannel activity in fibroblast cells under normal conditions and following ischemia reperfusion injury which elevates Cx43 levels, increases hemichannel activity and causes cell death. Our results showed that the effects of the mimetic peptide were concentration-dependent. High concentrations (100-300 μM significantly reduced Cx43 protein levels and GJIC within 2 h, while these effects did not appear until 6 h when using lower concentrations (10-30 μM. Cell death can be reduced when hemichannel opening and GJIC were minimised.

  3. BH3 Mimetics Reactivate Autophagic Cell Death in Anoxia-Resistant Malignant Glioma Cells

    Directory of Open Access Journals (Sweden)

    Holger Hetschko

    2008-08-01

    Full Text Available Here, we investigated the specific roles of Bcl-2 family members in anoxia tolerance of malignant glioma. Flow cytometry analysis of cell death in 17 glioma cell lines revealed drastic differences in their sensitivity to oxygen withdrawal (<0.1% O2. Cell death correlated with mitochondrial depolarization, cytochrome C release, and translocation of green fluorescent protein (GFP-tagged light chain 3 to autophagosomes but occurred in the absence of caspase activation or phosphatidylserine exposure. In both sensitive and tolerant glioma cell lines, anoxia caused a significant up-regulation of BH3-only genes previously implicated in mediating anoxic cell death in other cell types (BNIP3, NIX, PUMA, and Noxa. In contrast, we detected a strong correlation between anoxia resistance and high expression levels of antiapoptotic Bcl-2 family proteins Bcl-xL, Bcl-2, and Mcl-1 that function to neutralize the proapoptotic activity of BH3-only proteins. Importantly, inhibition of both Bcl-2 and Bcl-xL with the small-molecule BH3 mimetics HA14-1 and BH3I-2′ and by RNA interference reactivated anoxia-induced autophagic cell death in previously resistant glioma cells. Our data suggest that endogenous BH3-only protein induction may not be able to compensate for the high expression of antiapoptotic Bcl-2 family proteins in anoxia-resistant astrocytomas. They also support the conjecture that BH3 mimetics may represent an exciting new approach for the treatment of malignant glioma.

  4. Spinal Plasticity and Behavior: BDNF-Induced Neuromodulation in Uninjured and Injured Spinal Cord

    Directory of Open Access Journals (Sweden)

    Sandra M. Garraway

    2016-01-01

    Full Text Available Brain-derived neurotrophic factor (BDNF is a member of the neurotrophic factor family of signaling molecules. Since its discovery over three decades ago, BDNF has been identified as an important regulator of neuronal development, synaptic transmission, and cellular and synaptic plasticity and has been shown to function in the formation and maintenance of certain forms of memory. Neural plasticity that underlies learning and memory in the hippocampus shares distinct characteristics with spinal cord nociceptive plasticity. Research examining the role BDNF plays in spinal nociception and pain overwhelmingly suggests that BDNF promotes pronociceptive effects. BDNF induces synaptic facilitation and engages central sensitization-like mechanisms. Also, peripheral injury-induced neuropathic pain is often accompanied with increased spinal expression of BDNF. Research has extended to examine how spinal cord injury (SCI influences BDNF plasticity and the effects BDNF has on sensory and motor functions after SCI. Functional recovery and adaptive plasticity after SCI are typically associated with upregulation of BDNF. Although neuropathic pain is a common consequence of SCI, the relation between BDNF and pain after SCI remains elusive. This article reviews recent literature and discusses the diverse actions of BDNF. We also highlight similarities and differences in BDNF-induced nociceptive plasticity in naïve and SCI conditions.

  5. BDNF Val66Met polymorphism interacts with sex to influence bimanual motor control in healthy humans

    NARCIS (Netherlands)

    Smolders, R.; Rijpkema, M.J.P.; Franke, B.; Fernandez, G.S.E.

    2012-01-01

    Brain-derived neurotrophic factor (BDNF) plays a critical role in brain development. A common single nucleotide polymorphism in the gene encoding BDNF (rs6265, Val66Met) affects BDNF release and has been associated with altered learning and memory performance, and with structural changes in brain mo

  6. An Experimental Study of the Regulation of BDNF/TrkB Signal Pathway by Different Isoforms of TrkB in Epileptic Hippocampal Neurons%TrkB不同亚型对癫海马神经元BDNF/TrkB信号通路调控的研究

    Institute of Scientific and Technical Information of China (English)

    吴秋静; 常伟; 潘立平; 宋毅军; 赵文

    2014-01-01

    Objective To investigate the mechanism of brain derived neurotrophic factor (BDNF) regulated by differ-ent isoforms of tyrosine kinase receptor B (TrkB) in epileptic hippocampal neurons. Methods Primary hippocampal neu-rons were cultured in vitro for 7 days, and divided into two groups, ALLN (calcineurin inhibitor) group and Anisomycin (trans-lation inhibitor) group. ALLN group included control group, control+BDNF group, epilepsy group, epilepsy+BDNF group, control+ALLN group, epilepsy+ALLN group and epilepsy+ALLN+BDNF group. Anisomycin group was sub-divided into con-trol group, control+BDNF group, epilepsy group, epilepsy+BDNF group, control+Anisomycin group, epilepsy+Anisomycin group and epilepsy+Anisomycin+BDNF group. The immunofluorescent technique was used to identificate the hippocampal neurons. Epileptiform discharges were detected by electrophysiological techniques. Western blot assay was used to deter-mine the protein expression of TrkB and phosphorylated TrkB (p-TrkB) in all cell groups. Results (1) In ALLN group, the gray value of p-TrkB/TrkB was higher in control+BDNF group compared with that of control group, the value was higher in epilepsy+BDNF group than that of epilepsy group but was lower than that of control+BDNF group. The gray value of p-TrkB/TrkB was lower in epilepsy+ALLN+BDNF group than that of epilepsy+BDNF group, but no significant difference compared with that of epilepsy+ALLN group. (2) In Anisomycin group:the gray value of p-TrkB/TrkB was higher in control+BDNF group than that of control group. The gray value of p-TrkB/TrkB was higher in epilepsy+BDNF group than that of epilepsy group, but which was lower than that of control+BDNF group. The gray value of p-TrkB/TrkB was higher in epilepsy+Aniso-mycin+BDNF group than that of epilepsy+BDNF group and epilepsy+Anisomycin group. Conclusion The decreased ex-pression of TrkB.T can improve the inhibition of BDNF/TrkB signaling, and BDNF can activate BDNF/TrkB signal pathway in epileptic

  7. Effects of phenytoin and lamotrigine treatment on serum BDNF levels in offsprings of epileptic rats.

    Science.gov (United States)

    Soysal, Handan; Doğan, Zümrüt; Kamışlı, Özden

    2016-04-01

    The role of brain-derived neurotrophic factor (BDNF) is to promote and modulate neuronal responses across neurotransmitter systems in the brain. Therefore, abnormal BDNF signaling may be associated with the pathophysiology of schizophrenia. Low BDNF levels have been reported in brains and serums of patients with psychotic disorders. In the present study, we investigated the effects of antiepileptic drugs on BDNF in developing rats. Pregnant rats were treated with phenytoin (PHT), lamotrigine (LTG) and folic acid for long-term, all through their gestational periods. Experimental epilepsy (EE) model was applied in pregnant rats. Epileptic seizures were determined with electroencephalography. After birth, serum BDNF levels were measured in 136 newborn rats on postnatal day (PND) 21 and postnatal day 38. In postnatal day 21, serum BDNF levels of experimental epilepsy group were significantly lower compared with PHT group. This decrease is statistically significant. Serum BDNF levels increased in the group LTG. This increase compared with LTG+EE group was statistically significant. In the folic acid (FA) group, levels of serum BDNF decreased statistically significantly compared to the PHT group. On postnatal day 38, no significant differences were found among the groups for serum BDNF levels. We concluded that, the passed seizures during pregnancy adversely affect fetal brain development, lowering of serum BDNF levels. PHT use during pregnancy prevents seizure-induced injury by increasing the levels of BDNF. About the increase level of BDNF, LTG is much less effective than PHT, the positive effect of folic acid on serum BDNF levels was not observed. LTG increase in BDNF is much less effective than PHT, folic acid did not show a positive effect on serum BDNF levels. Epilepsy affects fetal brain development during gestation in pregnant rats, therefore anti-epileptic therapy should be continued during pregnancy. PMID:26706181

  8. Cerebral 5-HT2A receptor and serotonin transporter binding in humans are not affected by the val66met BDNF polymorphism status or blood BDNF levels

    DEFF Research Database (Denmark)

    Klein, Anders Bue; Trajkovska, Viktorija; Erritzoe, David;

    2010-01-01

    Recent studies have proposed an interrelation between the brain-derived neurotrophic factor (BDNF) val66met polymorphism and the serotonin system. In this study, we investigated whether the BDNF val66met polymorphism or blood BDNF levels are associated with cerebral 5-hydroxytryptamine 2A (5-HT(2A......)) receptor or serotonin transporter (SERT) binding in healthy subjects. No statistically significant differences in 5-HT(2A) receptor or SERT binding were found between the val/val and met carriers, nor were blood BDNF values associated with SERT binding or 5-HT(2A) receptor binding. In conclusion, val66met...... BDNF polymorphism status is not associated with changes in the serotonergic system. Moreover, BDNF levels in blood do not correlate with either 5-HT(2A) or SERT binding....

  9. Catalytic mechanism of Cu(p-OTs)2/ethanolamine as mimetic enzyme

    Institute of Scientific and Technical Information of China (English)

    宋继国; 沈培康

    2004-01-01

    The electrochemical behaviors of various copper salts complexes coordinated with equal molar ethanolamine were studied, and those of Cu(p-OTs)2 and Cu(p-OTs)2/ethanolamine(1:1) complex in CH3OH or DMF were characterized. The results show that the reduction of Cu( Ⅱ ) in Cu(p-OTs)2 is via one two-electron step mechanism both in CH3 OH and DMF. The reduction mechanism transforms to two one-electron steps in the case of Cu (p-OTs)2/ethanolamine(1:1) in DMF. However, it does not change in CH3 OH. All the Cu( Ⅱ )/ethanolamine(1:1) with the electrochemical reactions are through two one-electron steps, and can act as mimetic enzyme to oxidize 1, 1'-bi-2-naphthol. The Cu( Ⅱ )/ethanolamine(1:1) with electrochemical reactions through one two-electron step could not act as mimetic enzyme. It is concluded that the transformation between centre Cu( Ⅱ ) and Cu( Ⅰ ) is the crucial condition for the catalytic activity of copper-amine complex.

  10. Inhibition of Antiapoptotic BCL-XL, BCL-2, and MCL-1 Proteins by Small Molecule Mimetics

    Directory of Open Access Journals (Sweden)

    D.S. Dalafave

    2010-08-01

    Full Text Available Informatics and computational design methods were used to create new molecules that could potentially bind antiapoptotic proteins, thus promoting death of cancer cells. Apoptosis is a cellular process that leads to the death of damaged cells. Its malfunction can cause cancer and poor response to conventional chemotherapy. After being activated by cellular stress signals, proapoptotic proteins bind antiapoptotic proteins, thus allowing apoptosis to go forward. An excess of antiapoptotic proteins can prevent apoptosis. Designed molecules that mimic the roles of proapoptotic proteins can promote the death of cancer cells. The goal of our study was to create new putative mimetics that could simultaneously bind several antiapoptotic proteins. Five new small molecules were designed that formed stable complexes with BCL-2, BCL-XL, and MCL-1 antiapoptotic proteins. These results are novel because, to our knowledge, there are not many, if any, small molecules known to bind all three proteins. Drug-likeness studies performed on the designed molecules, as well as previous experimental and preclinical studies on similar agents, strongly suggest that the designed molecules may indeed be promising drug candidates. All five molecules showed “drug-like” properties and had overall drug-likeness scores between 81% and 96%. A single drug based on these mimetics should cost less and cause fewer side effects than a combination of drugs each aimed at a single protein. Computer-based molecular design promises to accelerate drug research by predicting potential effectiveness of designed molecules prior to laborious experiments and costly preclinical trials.

  11. Synthesis of cellulose nanocrystals carrying tyrosine sulfate mimetic ligands and inhibition of alphavirus infection.

    Science.gov (United States)

    Zoppe, Justin O; Ruottinen, Ville; Ruotsalainen, Janne; Rönkkö, Seppo; Johansson, Leena-Sisko; Hinkkanen, Ari; Järvinen, Kristiina; Seppälä, Jukka

    2014-04-14

    We present two facile approaches for introducing multivalent displays of tyrosine sulfate mimetic ligands on the surface of cellulose nanocrystals (CNCs) for application as viral inhibitors. We tested the efficacy of cellulose nanocrystals, prepared either from cotton fibers or Whatman filter paper, to inhibit alphavirus infectivity in Vero (B) cells. Cellulose nanocrystals were produced by sulfuric acid hydrolysis leading to nanocrystal surfaces decorated with anionic sulfate groups. When the fluorescent marker expressing Semliki Forest virus vector, VA7-EGFP, was incubated with CNCs, strong inhibition of virus infectivity was achieved, up to 100 and 88% for cotton and Whatman CNCs, respectively. When surface sulfate groups of CNCs were exchanged for tyrosine sulfate mimetic groups (i.e. phenyl sulfonates), improved viral inhibition was attained. Our observations suggest that the conjugation of target-specific functionalities to CNC surfaces provides a means to control their antiviral activity. Multivalent CNCs did not cause observable in vitro cytotoxicity to Vero (B) cells or human corneal epithelial (HCE-T) cells, even within the 100% virus-inhibitory concentrations. Based on the similar chemistry of known polyanionic inhibitors, our results suggest the potential application of CNCs as inhibitors of other viruses, such as human immunodeficiency virus (HIV) and herpes simplex viruses. PMID:24628489

  12. GM-3 Lactone Mimetic Interacts with CD4 and HIV-1 Env Proteins, Hampering HIV-1 Infection without Inducing a Histopathological Alteration.

    Science.gov (United States)

    Richichi, Barbara; Pastori, Claudia; Gherardi, Stefano; Venuti, Assunta; Cerreto, Antonella; Sanvito, Francesca; Toma, Lucio; Lopalco, Lucia; Nativi, Cristina

    2016-08-12

    Glycosphingolipids (GSLs) are involved in HIV-1 entry. GM-3 ganglioside, a widespread GSL, affects HIV entry and infection in different ways, depending on the concentration, through its anchoring activity in lipid rafts. This explains why the induction of an altered GSLs metabolism was a tempting approach to reducing HIV-1 cell infection. This study assayed the biological properties of a synthetic GM-3 lactone mimetic, 1, aimed at blocking HIV-1 infection without inducing the adverse events expected by an altered metabolism of GLSs in vivo. The mimetic, conjugated to immunogenic protein ovalbumin and multivalently presented, was able to bind the CD4 molecule with high affinity and block its engagement with gp120, thus inhibiting virus entry. Elicited antimimetic antibodies were also able to block HIV-1 infection in vitro, with activity complementary to that observed for 1. These preliminary results show that the use of GSLs mimetics can be a novel promising mode to block HIV-1 infection and that 1 and other GSL mimetics deserve further attention. PMID:27626296

  13. Reduced brain-derived neurotrophic factor (BDNF) mRNA expression and presence of BDNF-immunoreactive granules in the spinocerebellar ataxia type 6 (SCA6) cerebellum.

    Science.gov (United States)

    Takahashi, Makoto; Ishikawa, Kinya; Sato, Nozomu; Obayashi, Masato; Niimi, Yusuke; Ishiguro, Taro; Yamada, Mitsunori; Toyoshima, Yasuko; Takahashi, Hitoshi; Kato, Takeo; Takao, Masaki; Murayama, Shigeo; Mori, Osamu; Eishi, Yoshinobu; Mizusawa, Hidehiro

    2012-12-01

    Spinocerebellar ataxia type 6 (SCA6) is an autosomal-dominant neurodegenerative disorder caused by a small expansion of tri-nucleotide (CAG) repeat encoding polyglutamine (polyQ) in the gene for α(1A) voltage-dependent calcium channel (Ca(v) 2.1). Thus, this disease is one of the nine neurodegenerative disorders called polyQ diseases. The Purkinje cell predominant neuronal loss is the characteristic neuropathology of SCA6, and a 75-kDa carboxy-terminal fragment (CTF) of Ca(v) 2.1 containing polyQ, which remains soluble in normal brains, becomes insoluble in the cytoplasm of SCA6 Purkinje cells. Because the suppression of the brain-derived neurotrophic factor (BDNF) expression is a potentially momentous phenomenon in many other polyQ diseases, we implemented BDNF expression analysis in SCA6 human cerebellum using quantitative RT-PCR for the BDNF mRNA, and by immunohistochemistry for the BDNF protein. We observed significantly reduced BDNF mRNA levels in SCA6 cerebellum (n = 3) compared to controls (n = 6) (Mann-Whitney U-test, P = 0.0201). On immunohistochemistry, BDNF protein was only weakly stained in control cerebellum. On the other hand, we found numerous BDNF-immunoreactive granules in dendrites of SCA6 Purkinje cells. We did not observe similar BDNF-immunoreactive granules in other polyQ diseases, such as Huntington's disease or SCA2. As we often observed that the 1C2-positive Ca(v) 2.1 aggregates existed more proximally than the BDNF-positive granules in the dendrites, we speculated that the BDNF protein trafficking in dendrites may be disturbed by Ca(v) 2.1 aggregates in SCA6 Purkinje cells. We conclude that the SCA6 pathogenic mechanism associates with the BDNF mRNA expression reduction and abnormal localization of BDNF protein.

  14. Circulating brain derived neurotrophic factor (BDNF) and frequency of BDNF positive T cells in peripheral blood in human ischemic stroke: Effect on outcome.

    Science.gov (United States)

    Chan, Adeline; Yan, Jun; Csurhes, Peter; Greer, Judith; McCombe, Pamela

    2015-09-15

    The aim of this study was to measure the levels of circulating BDNF and the frequency of BDNF-producing T cells after acute ischaemic stroke. Serum BDNF levels were measured by ELISA. Flow cytometry was used to enumerate peripheral blood leukocytes that were labelled with antibodies against markers of T cells, T regulatory cells (Tregs), and intracellular BDNF. There was a slight increase in serum BDNF levels after stroke. There was no overall difference between stroke patients and controls in the frequency of CD4(+) and CD8(+) BDNF(+) cells, although a subgroup of stroke patients showed high frequencies of these cells. However, there was an increase in the percentage of BDNF(+) Treg cells in the CD4(+) population in stroke patients compared to controls. Patients with high percentages of CD4(+) BDNF(+) Treg cells had a better outcome at 6months than those with lower levels. These groups did not differ in age, gender or initial stroke severity. Enhancement of BDNF production after stroke could be a useful means of improving neuroprotection and recovery after stroke.

  15. Epibranchial placode-derived neurons produce BDNF required for early sensory neuron development.

    Science.gov (United States)

    Harlow, Danielle E; Yang, Hui; Williams, Trevor; Barlow, Linda A

    2011-02-01

    In mice, BDNF provided by the developing taste epithelium is required for gustatory neuron survival following target innervation. However, we find that expression of BDNF, as detected by BDNF-driven β-galactosidase, begins in the cranial ganglia before its expression in the central (hindbrain) or peripheral (taste papillae) targets of these sensory neurons, and before gustatory ganglion cells innervate either target. To test early BDNF function, we examined the ganglia of bdnf null mice before target innervation, and found that while initial neuron survival is unaltered, early neuron development is disrupted. In addition, fate mapping analysis in mice demonstrates that murine cranial ganglia arise from two embryonic populations, i.e., epibranchial placodes and neural crest, as has been described for these ganglia in non-mammalian vertebrates. Only placodal neurons produce BDNF, however, which indicates that prior to innervation, early ganglionic BDNF produced by placode-derived cells promotes gustatory neuron development.

  16. Dynamical behavior in mimetic F(R) gravity

    CERN Document Server

    Leon, Genly

    2015-01-01

    We investigate the cosmological behaviour of mimetic F(R) gravity. This scenario is the F(R) extension of usual mimetic gravity classes, which are based on re-parametrizations of the metric using new, but not extra, degrees of freedom, that can lead to a wider family of solutions. Performing a detailed dynamical analysis for exponential, power-law, and arbitrary F(R) forms, we extracted the corresponding critical points. Interestingly enough, we found that although the new features of mimetic F(R) gravity can affect the universe evolution at early and intermediate times, at late times they will not have any effect, and the universe will result at stable states that coincide with those of usual F(R) gravity. However, this feature holds for the late-time background evolution only. On the contrary, the behaviour of the perturbations is expected to be different since the new term contributes to the perturbations even if it does not contribute at the the background level.

  17. Dark Energy Oscillations in Mimetic $F(R)$ Gravity

    CERN Document Server

    Odintsov, S D

    2016-01-01

    In this paper we address the problem of dark energy oscillations in the context of mimetic $F(R)$ gravity with potential. The issue of dark energy oscillations can be a problem in some models of ordinary $F(R)$ gravity and a remedy that can make the oscillations milder is to introduce additional modifications in the functional form of the $F(R)$ gravity. As we demonstrate the power-law modifications are not necessary in the mimetic $F(R)$ case, and by appropriately choosing the mimetic potential and the Lagrange multiplier, it is possible to make the oscillations almost to vanish at the end of the matter domination era and during the late-time acceleration era. We examine the behavior of the dark energy equation of state parameter and of the total effective equation of state parameter as functions of the redshift and we compare the resulting picture with the ordinary $F(R)$ gravity case. As we also show, the present day values of the dark energy equation of state parameter and of the total effective equation ...

  18. Brain-Derived Neurotrophic Factor (BDNF) Promotes Cochlear Spiral Ganglion Cell Survival and Function in Deafened, Developing Cats

    OpenAIRE

    Leake, Patricia A.; Hradek, Gary T.; Hetherington, Alexander M.; Stakhovskaya, Olga

    2011-01-01

    Postnatal development and survival of spiral ganglion (SG) neurons depend upon both neural activity and neurotrophic support. Our previous studies showed that electrical stimulation from a cochlear implant only partly prevents SG degeneration after early deafness. Thus, neurotrophic agents that might be combined with an implant to improve neural survival are of interest. Recent studies reporting that BDNF promotes SG survival after deafness, have been conducted in rodents and limited to relat...

  19. Antidepressant-like effects of curcumin in WKY rat model of depression is associated with an increase in hippocampal BDNF

    Science.gov (United States)

    Hurley, Laura L.; Akinfiresoye, Luli; Nwulia, Evaristus; Kamiya, Atsushi; Kulkarni, Amol; Tizabi, Yousef

    2012-01-01

    Curcumin is the principal active ingredient found in turmeric (Curcuma longa), a plant used in traditional Asian diets and herbal medicines. It is known to have a wide range of biological actions including antidepressant-like effects which have been observed in stress-induced depression models. This study was designed to investigate the antidepressant potential of curcumin in a non-induced model of depression. Moreover, since brain derived neurotrophic factor (BDNF) has been implicated in antidepressant effects of many drugs, we also evaluated the effects of curcumin on BDNF in the hippocampus. Adult male Wistar Kyoto (WKY) rats, a putative model of depression, were injected acutely or chronically (10 d) with 50, 100, and 200mg/kg curcumin. Open field locomotor activity (OFLA) and forced swim test (FST), a measure of helplessness, were measured 1 hour after acute and 18–20 hours after last chronic injection. Results showed a dose-dependent reduction of immobility in the FST by curcumin in both acute and chronic studies, without any significant effect on OFLA. The effect of higher chronic curcumin dose in FST was still evident a week later. Chronic curcumin also resulted in a dose-dependent increase in hippocampal BDNF. This data provides evidence for an antidepressant-like effect of curcumin, possibly through increased neurotrophic activity, in the WKY model of depression, and support the notion that curcumin may prove an effective and lasting natural antidepressant. PMID:23142609

  20. Noopept stimulates the expression of NGF and BDNF in rat hippocampus.

    Science.gov (United States)

    Ostrovskaya, R U; Gudasheva, T A; Zaplina, A P; Vahitova, Ju V; Salimgareeva, M H; Jamidanov, R S; Seredenin, S B

    2008-09-01

    We studied the effect of original dipeptide preparation Noopept (N-phenylacetyl-L-prolylglycine ethyl ester, GVS-111) with nootropic and neuroprotective properties on the expression of mRNA for neurotropic factors NGF and BDNF in rat hippocampus. Expression of NGF and BDNF mRNA in the cerebral cortex and hippocampus was studied by Northern blot analysis. Taking into account the fact that pharmacological activity of Noopept is realized after both acute and chronic treatment, we studied the effect of single and long-term treatment (28 days) with this drug. Expression of the studied neurotropic factors in the cerebral cortex was below the control after single administration of Noopept, while chronic administration caused a slight increase in BDNF expression. In the hippocampus, expression of mRNA for both neurotrophins increased after acute administration of Noopept. Chronic treatment with Noopept was not followed by the development of tolerance, but even potentiated the neurotrophic effect. These changes probably play a role in neuronal restoration. We showed that the nootropic drug increases expression of neurotrophic factors in the hippocampus. Our results are consistent with the hypothesis that neurotrophin synthesis in the hippocampus determines cognitive function, particularly in consolidation and delayed memory retrieval. Published data show that neurotrophic factor deficiency in the hippocampus is observed not only in advanced Alzheimer's disease, but also at the stage of mild cognitive impairment (pre-disease state). In light of this our findings suggest that Noopept holds much promise to prevent the development of Alzheimer's disease in patients with mild cognitive impairment. Moreover, therapeutic effectiveness of Noopept should be evaluated at the initial stage of Alzheimer's disease. PMID:19240853

  1. Alterations of BDNF and trkB mRNA expression in the 6-hydroxydopamine-induced model of preclinical stages of Parkinson's disease: an influence of chronic pramipexole in rats.

    Directory of Open Access Journals (Sweden)

    Klemencja Berghauzen-Maciejewska

    Full Text Available Our recent study has indicated that a moderate lesion of the mesostriatal and mesolimbic pathways in rats, modelling preclinical stages of Parkinson's disease, induces a depressive-like behaviour which is reversed by chronic treatment with pramipexole. The purpose of the present study was to examine the role of brain derived neurotrophic factor (BDNF signalling in the aforementioned model of depression. Therefore, we investigated the influence of 6-hydoxydopamine (6-OHDA administration into the ventral region of the caudate-putamen on mRNA levels of BDNF and tropomyosin-related kinase B (trkB receptor. The BDNF and trkB mRNA levels were determined in the nigrostriatal and limbic structures by in situ hybridization 2 weeks after the operation. Pramipexole (1 mg/kg sc twice a day and imipramine (10 mg/kg ip once a day were injected for 2 weeks. The lesion lowered the BDNF and trkB mRNA levels in the hippocampus [CA1, CA3 and dentate gyrus (DG] and amygdala (basolateral/lateral as well as the BDNF mRNA content in the habenula (medial/lateral. The lesion did not influence BDNF and trkB expression in the caudate-putamen, substantia nigra, nucleus accumbens (shell and core and ventral tegmental area (VTA. Chronic imipramine reversed the lesion-induced decreases in BDNF mRNA in the DG. Chronic pramipexole increased BDNF mRNA, but decreased trkB mRNA in the VTA in lesioned rats. Furthermore, it reduced BDNF and trkB mRNA expression in the shell and core of the nucleus accumbens, BDNF mRNA in the amygdala and trkB mRNA in the caudate-putamen in these animals. The present study indicates that both the 6-OHDA-induced dopaminergic lesion and chronic pramipexole influence BDNF signalling in limbic structures, which may be related to their pro-depressive and antidepressant activity in rats, respectively.

  2. Mutation screen of the brain derived neurotrophic factor gene (BDNF): identification of several genetic variants and association studies in patients with obesity, eating disorders, and attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Friedel, S; Horro, F Fontenla; Wermter, A K; Geller, F; Dempfle, A; Reichwald, K; Smidt, J; Brönner, G; Konrad, K; Herpertz-Dahlmann, B; Warnke, A; Hemminger, U; Linder, M; Kiefl, H; Goldschmidt, H P; Siegfried, W; Remschmidt, H; Hinney, A; Hebebrand, J

    2005-01-01

    Several lines of evidence indicate an involvement of brain derived neurotrophic factor (BDNF) in body weight regulation and activity: heterozygous Bdnf knockout mice (Bdnf(+/-)) are hyperphagic, obese, and hyperactive; furthermore, central infusion of BDNF leads to severe, dose-dependent appetite suppression and weight loss in rats. We searched for the role of BDNF variants in obesity, eating disorders, and attention-deficit/hyperactivity disorder (ADHD). A mutation screen (SSCP and DHPLC) of the translated region of BDNF in 183 extremely obese children and adolescents and 187 underweight students was performed. Additionally, we genotyped two common polymorphisms (rs6265: p.V66M; c.-46C > T) in 118 patients with anorexia nervosa, 80 patients with bulimia nervosa, 88 patients with ADHD, and 96 normal weight controls. Three rare variants (c.5C > T: p.T2I; c.273G > A; c.*137A > G) and the known polymorphism (p.V66M) were identified. A role of the I2 allele in the etiology of obesity cannot be excluded. We found no association between p.V66M or the additionally genotyped variant c.-46C > T and obesity, ADHD or eating disorders. This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148-7299:1/suppmat/index.html. PMID:15457498

  3. Running throughout middle-age improves memory function, hippocampal neurogenesis and BDNF levels in female C57Bl/6J mice.

    NARCIS (Netherlands)

    M.W. Marlatt; M.C. Potter; P.J. Lucassen; H. van Praag

    2012-01-01

    Age-related memory loss is considered to commence at middle-age and coincides with reduced adult hippocampal neurogenesis and neurotrophin levels. Consistent physical activity at midlife may preserve brain-derived neurotrophic factor (BDNF) levels, new cell genesis and learning. In the present study

  4. An evaluation of the effects of acute and chronic L-tyrosine administration on BDNF levels and BDNF mRNA expression in the rat brain.

    Science.gov (United States)

    Ferreira, Gabriela K; Scaini, Giselli; Jeremias, Isabela C; Carvalho-Silva, Milena; Gonçalves, Cinara L; Pereira, Talita C B; Oliveira, Giovanna M T; Kist, Luiza W; Bogo, Maurício R; Schuck, Patrícia F; Ferreira, Gustavo C; Streck, Emilio L

    2014-04-01

    Tyrosinemia type II, which is also known as Richner-Hanhart syndrome, is an inborn error of metabolism that is due to a block in the transamination reaction that converts tyrosine to p-hydroxyphenylpyruvate. Because the mechanisms of neurological dysfunction in hypertyrosinemic patients are poorly known and the symptoms of these patients are related to the central nervous system, the present study evaluated brain-derived neurotrophic factor (BDNF) levels and bdnf mRNA expression in young rats and during growth. In our acute protocol, Wistar rats (10 and 30 days old) were killed 1 h after a single intraperitoneal L-tyrosine injection (500 mg/kg) or saline. Chronic administration consisted of L-tyrosine (500 mg/kg) or saline injections 12 h apart for 24 days in Wistar rats (7 days old), and the rats were killed 12 h after the last injection. The brains were rapidly removed, and we evaluated the BDNF levels and bdnf mRNA expression. The present results showed that the acute administration of L-tyrosine decreased both BDNF and bdnf mRNA levels in the striatum of 10-day-old rats. In the 30-day-old rats, we observed decreased BDNF levels without modifications in bdnf transcript level in the hippocampus and striatum. Chronic administration of L-tyrosine increased the BDNF levels in the striatum of rats during their growth, whereas bdnf mRNA expression was not altered. We hypothesize that oxidative stress can interact with the BDNF system to modulate synaptic plasticity and cognitive function. The present results enhance our knowledge of the pathophysiology of hypertyrosinemia.

  5. A novel anti-inflammatory role of NCAM-derived mimetic peptide, FGL

    DEFF Research Database (Denmark)

    Downer, Eric J; Cowley, Thelma R; Lyons, Anthony;

    2010-01-01

    novel anti-inflammatory agent. Administration of FGL to aged rats attenuated the increased expression of markers of activated microglia, the increase in pro-inflammatory interleukin-1beta (IL-1beta) and the impairment in long-term potentiation (LTP). We report that the age-related increase in microglial......Age-related cognitive deficits in hippocampus are correlated with neuroinflammatory changes, typified by increased pro-inflammatory cytokine production and microglial activation. We provide evidence that the neural cell adhesion molecule (NCAM)-derived mimetic peptide, FG loop (FGL), acts as a...... CD200 in vitro. We provide evidence that the increase in CD200 is reliant on IL-4-induced extracellular signal-regulated kinase (ERK) signal transduction. These findings provide the first evidence of a role for FGL as an anti-inflammatory agent and identify a mechanism by which FGL controls...

  6. Behavioral phenotype and BDNF differences related to apoE isoforms and sex in young transgenic mice

    DEFF Research Database (Denmark)

    Reverte, Ingrid; Klein, Anders Bue; Ratner, Cecilia;

    2012-01-01

    , very little information is available on apoE2 genotype. In the present study, we have characterized behavioral and learning phenotypes in young transgenic mice apoE2, apoE3 and apoE4 of both sexes. We have also determined the levels of brain-derived neurotrophic factor (BDNF) and its receptor Trk...... in the exploration of an open-field, which is compatible with a hyperactive behavior, was found in apoE2 females, while a decreased activity was observed in apoE4 mice. Increased BDNF levels in the frontal cortex were observed in apoE2 mice compared to apoE3. These results underscore behavioral differences between...

  7. The BH3 Mimetic Obatoclax Accumulates in Lysosomes and Causes Their Alkalinization.

    Directory of Open Access Journals (Sweden)

    Vasileios A Stamelos

    Full Text Available Obatoclax belongs to a class of compounds known as BH3 mimetics which function as antagonists of Bcl-2 family apoptosis regulators. It has undergone extensive preclinical and clinical evaluation as a cancer therapeutic. Despite this, it is clear that obatoclax has additional pharmacological effects that contribute to its cytotoxic activity. It has been claimed that obatoclax, either alone or in combination with other molecularly targeted therapeutics, induces an autophagic form of cell death. In addition, obatoclax has been shown to inhibit lysosomal function, but the mechanism of this has not been elucidated. We have evaluated the mechanism of action of obatoclax in eight ovarian cancer cell lines. Consistent with its function as a BH3 mimetic, obatoclax induced apoptosis in three cell lines. However, in the remaining cell lines another form of cell death was evident because caspase activation and PARP cleavage were not observed. Obatoclax also failed to show synergy with carboplatin and paclitaxel, chemotherapeutic agents which we have previously shown to be synergistic with authentic Bcl-2 family antagonists. Obatoclax induced a profound accumulation of LC-3 but knockdown of Atg-5 or beclin had only minor effects on the activity of obatoclax in cell growth assays suggesting that the inhibition of lysosomal function rather than stimulation of autophagy may play a more prominent role in these cells. To evaluate how obatoclax inhibits lysosomal function, confocal microscopy studies were conducted which demonstrated that obatoclax, which contains two basic pyrrole groups, accumulates in lysosomes. Studies using pH sensitive dyes demonstrated that obatoclax induced lysosomal alkalinization. Furthermore, obatoclax was synergistic in cell growth/survival assays with bafilomycin and chloroquine, two other drugs which cause lysosomal alkalinization. These studies explain, for the first time, how obatoclax inhibits lysosomal function and suggest that

  8. Antidepressive and BDNF effects of enriched environment treatment across ages in mice lacking BDNF expression through promoter IV

    Science.gov (United States)

    Jha, S; Dong, B E; Xue, Y; Delotterie, D F; Vail, M G; Sakata, K

    2016-01-01

    Reduced promoter IV-driven expression of brain-derived neurotrophic factor (BDNF) is implicated in stress and major depression. We previously reported that defective promoter IV (KIV) caused depression-like behavior in young adult mice, which was reversed more effectively by enriched environment treatment (EET) than antidepressants. The effects of promoter IV-BDNF deficiency and EET over the life stages remain unknown. Since early-life development (ED) involves dynamic epigenetic processes, we hypothesized that EET during ED would provide maximum antidepressive effects that would persist later in life due to enhanced, long-lasting BDNF induction. We tested this hypothesis by determining EET effects across three life stages: ED (0–2 months), young adult (2–4 months), and old adult (12–14 months). KIV mice at all life stages showed depression-like behavior in the open-field and tail-suspension tests compared with wild-type mice. Two months of EET reduced depression-like behavior in ED and young adult, but not old adult mice, with the largest effect in ED KIV mice. This effect lasted for 1 month after discontinuance of EET only in ED mice. BDNF protein induction by EET in the hippocampus and frontal cortex was also the largest in ED mice and persisted only in the hippocampus of ED KIV mice after discontinuance of EET. No gender-specific effects were observed. The results suggest that defective promoter IV causes depression-like behavior, regardless of age and gender, and that EET during ED is particularly beneficial to individuals with promoter IV-BDNF deficiency, while additional treatment may be needed for older adults. PMID:27648918

  9. Antidepressive and BDNF effects of enriched environment treatment across ages in mice lacking BDNF expression through promoter IV.

    Science.gov (United States)

    Jha, S; Dong, B E; Xue, Y; Delotterie, D F; Vail, M G; Sakata, K

    2016-01-01

    Reduced promoter IV-driven expression of brain-derived neurotrophic factor (BDNF) is implicated in stress and major depression. We previously reported that defective promoter IV (KIV) caused depression-like behavior in young adult mice, which was reversed more effectively by enriched environment treatment (EET) than antidepressants. The effects of promoter IV-BDNF deficiency and EET over the life stages remain unknown. Since early-life development (ED) involves dynamic epigenetic processes, we hypothesized that EET during ED would provide maximum antidepressive effects that would persist later in life due to enhanced, long-lasting BDNF induction. We tested this hypothesis by determining EET effects across three life stages: ED (0-2 months), young adult (2-4 months), and old adult (12-14 months). KIV mice at all life stages showed depression-like behavior in the open-field and tail-suspension tests compared with wild-type mice. Two months of EET reduced depression-like behavior in ED and young adult, but not old adult mice, with the largest effect in ED KIV mice. This effect lasted for 1 month after discontinuance of EET only in ED mice. BDNF protein induction by EET in the hippocampus and frontal cortex was also the largest in ED mice and persisted only in the hippocampus of ED KIV mice after discontinuance of EET. No gender-specific effects were observed. The results suggest that defective promoter IV causes depression-like behavior, regardless of age and gender, and that EET during ED is particularly beneficial to individuals with promoter IV-BDNF deficiency, while additional treatment may be needed for older adults. PMID:27648918

  10. BDNF and COX-2 participate in anti-depressive mechanisms of catalpol in rats undergoing chronic unpredictable mild stress.

    Science.gov (United States)

    Wang, Jun-Ming; Yang, Lian-He; Zhang, Yue-Yue; Niu, Chun-Ling; Cui, Ying; Feng, Wei-Sheng; Wang, Gui-Fang

    2015-11-01

    Catalpol, a major compound in Rehmannia glutinosa with both medicinal and nutritional values, has been previously confirmed to shorten the duration of immobility in mice exposed to tail suspension and forced swimming tests. This study attempted to examine the anti-depressive mechanisms of catalpol in rats undergoing chronic unpredictable mild stress (CUMS) by involving brain-derived neurotrophic factor (BDNF) and cyclooxygenase-2 (COX-2). CUMS-exposed rats were given catalpol daily (5, 10, and 20mg/kg, ig) or a reference drug, fluoxetine hydrochloride (FH, 10mg/kg, ig), at 5 weeks after starting the CUMS procedure. Sucrose preference test was performed to observe depression-like behavior, and serum and brain tissues were used for neurochemical and fluorescent quantitative reverse transcription PCR analysis. CUMS induced depression-like behavior, whereas catalpol and FH administration attenuated this symptom. Moreover, CUMS caused excessively elevated levels of serum corticosterone, an index of hypothalamic-pituitary-adrenal (HPA) axis hyperactivation, in a manner attenuated by catalpol and FH administration. Catalpol administration also further decreased BDNF activities, downregulated the mRNA expression of BDNF and tropomyosin-related kinase B (TrkB), and reversed the excessive elevation in the activities and mRNA expression levels of COX-2 and prostaglandin E2 (PGE2) in the hippocampus and frontal cortex of rats undergoing CUMS. Results indicate that catalpol can ameliorate CUMS-induced depression-like behavior, and suggest its mechanisms may partially be ascribed to restoring HPA axis dysfunctions, upregulating BDNF expression and its cognate receptor TrkB, and downregulating COX-2 expression, thereby reducing PGE2 levels in the brain. PMID:26255123

  11. Brain-derived neurotrophic factor (BDNF) induces sustained intracellular Ca2+ elevation through the up-regulation of surface transient receptor potential 3 (TRPC3) channels in rodent microglia.

    Science.gov (United States)

    Mizoguchi, Yoshito; Kato, Takahiro A; Seki, Yoshihiro; Ohgidani, Masahiro; Sagata, Noriaki; Horikawa, Hideki; Yamauchi, Yusuke; Sato-Kasai, Mina; Hayakawa, Kohei; Inoue, Ryuji; Kanba, Shigenobu; Monji, Akira

    2014-06-27

    Microglia are immune cells that release factors, including proinflammatory cytokines, nitric oxide (NO), and neurotrophins, following activation after disturbance in the brain. Elevation of intracellular Ca(2+) concentration ([Ca(2+)]i) is important for microglial functions such as the release of cytokines and NO from activated microglia. There is increasing evidence suggesting that pathophysiology of neuropsychiatric disorders is related to the inflammatory responses mediated by microglia. Brain-derived neurotrophic factor (BDNF) is a neurotrophin well known for its roles in the activation of microglia as well as in pathophysiology and/or treatment of neuropsychiatric disorders. In this study, we sought to examine the underlying mechanism of BDNF-induced sustained increase in [Ca(2+)]i in rodent microglial cells. We observed that canonical transient receptor potential 3 (TRPC3) channels contribute to the maintenance of BDNF-induced sustained intracellular Ca(2+) elevation. Immunocytochemical technique and flow cytometry also revealed that BDNF rapidly up-regulated the surface expression of TRPC3 channels in rodent microglial cells. In addition, pretreatment with BDNF suppressed the production of NO induced by tumor necrosis factor α (TNFα), which was prevented by co-adiministration of a selective TRPC3 inhibitor. These suggest that BDNF induces sustained intracellular Ca(2+) elevation through the up-regulation of surface TRPC3 channels and TRPC3 channels could be important for the BDNF-induced suppression of the NO production in activated microglia. We show that TRPC3 channels could also play important roles in microglial functions, which might be important for the regulation of inflammatory responses and may also be involved in the pathophysiology and/or the treatment of neuropsychiatric disorders.

  12. The consequences of selective inhibition of signal transducer and activator of transcription 3 (STAT3) tyrosine705 phosphorylation by phosphopeptide mimetic prodrugs targeting the Src homology 2 (SH2) domain.

    Science.gov (United States)

    McMurray, John S; Mandal, Pijus K; Liao, Warren S; Klostergaard, Jim; Robertson, Fredika M

    2012-10-01

    Herein we review our progress on the development of phosphopeptide-based prodrugs targeting the SH2 domain of STAT3 to prevent recruitment to cytokine and growth factor receptors, activation, nuclear translocation and transcription of genes involved in cancer. We developed high affinity phosphopeptides (K I = 46-200 nM). Corresponding prodrugs inhibited constitutive and IL-6 induced Tyr705 phosphorylation at 0.5-1 μM in a variety of human cancer cell lines. They were not cytotoxic at 5 μM in vitro but they inhibited tumor growth in a human xenograft breast cancer model in mice, accompanied by reduced VEGF expression and angiogenesis. PMID:24058783

  13. Cisplatin-induced apoptosis in non-small-cell lung cancer cells is dependent on Bax- and Bak-induction pathway and synergistically activated by BH3-mimetic ABT-263 in p53 wild-type and mutant cells.

    Science.gov (United States)

    Matsumoto, Masaru; Nakajima, Wataru; Seike, Masahiro; Gemma, Akihiko; Tanaka, Nobuyuki

    2016-04-29

    Cisplatin is a highly effective anticancer drug for treatment of various tumors including non-small-cell lung cancer (NSCLC), and is especially useful in cases nonresponsive to molecular-targeted drugs. Accumulating evidence has shown that cisplatin activates the p53-dependent apoptotic pathway, but it also induces apoptosis in p53-mutated cancer cells. Here we demonstrated that DNA-damage inducible proapoptotic BH3 (Bcl-2 homology region 3)-only Bcl-2 family members, Noxa, Puma, Bim and Bid, are not involved in cisplatin-induced apoptosis in human NSCLC cell lines. In contrast, the expression of proapoptotic multidomain Bcl-2-family members, Bak and Bax, was induced by cisplatin in p53-dependent and -independent manners, respectively. Moreover, in wild-type p53-expressing cells, cisplatin mainly used the Bak-dependent apoptotic pathway, but this apoptotic pathway shifted to the Bax-dependent pathway by loss-of-function of p53. Furthermore, both Bak- and Bax-induced apoptosis was enhanced by the antiapoptotic Bcl-2 family member, Bcl-XL knockdown, but not by Mcl-1 knockdown. From this result, we tested the effect of ABT-263 (Navitoclax), the specific inhibitor of Bcl-2 and Bcl-XL, but not Mcl-1, and found that ABT-263 synergistically enhanced cisplatin-induced apoptosis in NSCLC cells in the presence or absence of p53. These results indicate a novel regulatory system in cisplatin-induced NSCLC cell apoptosis, and a candidate efficient combination chemotherapy method against lung cancers.

  14. Robust changes in expression of brain-derived neurotrophic factor (BDNF) mRNA and protein across the brain do not translate to detectable changes in BDNF levels in CSF or plasma.

    Science.gov (United States)

    Lanz, Thomas A; Bove, Susan E; Pilsmaker, Catherine D; Mariga, Abigail; Drummond, Elena M; Cadelina, Gregory W; Adamowicz, Wendy O; Swetter, Brentt J; Carmel, Sharon; Dumin, Jo Ann; Kleiman, Robin J

    2012-09-01

    Adult rats were treated acutely with peripheral kainic acid (KA), and changes in brain-derived neurotrophic factor (BDNF) mRNA and protein were tracked over time across multiple brain regions. Despite robust elevation in both mRNA and protein in multiple brain regions, plasma BDNF was unchanged and cerebrospinal fluid (CSF) BDNF levels remained undetectable. Primary neurons were then treated with KA. BDNF was similarly elevated within neurons, but was undetectable in neuronal media. Thus, while deficits in BDNF signaling have been implicated in a number of diseases, these data suggest that extracellular concentrations of BDNF may not be a facile biomarker for changes in neurons.

  15. CREB-BDNF Pathway Influences Alcohol Cue-Elicited Hyperactivation in Drinkers

    Science.gov (United States)

    Chen, Jiayu; Hutchison, Kent E.; Calhoun, Vince D.; Claus, Eric; Turner, Jessica A.; Sui, Jing; Liu, Jingyu

    2016-01-01

    Alcohol dependence (AD) is suggested to have polygenic risk factors and also exhibits neurological complications, strongly encouraging a translational study to explore the associations between aggregates of genetic variants and brain function alterations related to alcohol use. In this study, we used a semiblind multivariate approach, parallel independent component analysis with multiple references (pICA-MR) to investigate relationships of genome-wide single nucleotide polymorphisms (SNPs) with alcohol cue elicited brain activations in 326 healthy drinkers. The genetic component derived from the CREB-BDNF pathway reference was significantly associated (r = −0.36, p = 2.98×10−11) with an imaging component reflecting hyperactivation in precuneus, superior parietal lobule, and posterior cingulate for drinkers with more severe AD scores. The highlighted brain regions participate in many cognitive processes and have been robustly implicated in craving-related studies. The genetic factor highlighted the CREB and BDNF references, as well as other genes including GRM5, GRM7, GRID1, GRIN2A, PRKCA and PRKCB. Ingenuity Pathway Analysis indicated that the genetic component was enriched in synaptic plasticity, GABA and protein kinase A signaling. In summary, our findings suggest genetic variations in various neural plasticity and signaling pathways partially explain the variance of precuneus reactivity to alcohol cue which appears to be associated with AD severity. PMID:25939814

  16. Downregulated GABA and BDNF-TrkB Pathway in Chronic Cyclothiazide Seizure Model

    Directory of Open Access Journals (Sweden)

    Shuzhen Kong

    2014-01-01

    Full Text Available Cyclothiazide (CTZ has been reported to simultaneously enhance glutamate receptor excitation and inhibit GABAA receptor inhibition, and in turn it evokes epileptiform activities in hippocampal neurons. It has also been shown to acutely induce epileptic seizure behavior in freely moving rats. However, whether CTZ induced seizure rats could develop to have recurrent seizure still remains unknown. In the current study, we demonstrated that 46% of the CTZ induced seizure rats developed to have recurrent seizure behavior as well as epileptic EEG with a starting latency between 2 weeks and several months. In those chronic seizure rats 6 months after the seizure induction by the CTZ, our immunohistochemistry results showed that both GAD and GAT-1 were significantly decreased across CA1, CA3, and dentate gyrus area of the hippocampus studied. In addition, both BDNF and its receptor TrkB were also decreased in hippocampus of the chronic CTZ seizure rats. Our results indicate that CTZ induced seizure is capable of developing to have recurrent seizure, and the decreased GABA synthesis and transport as well as the impaired BDNF-TrkB signaling pathway may contribute to the development of the recurrent seizure. Thus, CTZ seizure rats may provide a novel animal model for epilepsy study and anticonvulsant drug testing in the future.

  17. p75 neurotrophin receptor and pro-BDNF promote cell survival and migration in clear cell renal cell carcinoma

    Science.gov (United States)

    Sánchez-Prieto, Ricardo; Saada, Sofiane; Naves, Thomas; Guillaudeau, Angélique; Perraud, Aurélie; Sindou, Philippe; Lacroix, Aurélie; Descazeaud, Aurélien; Lalloué, Fabrice; Jauberteau, Marie-Odile

    2016-01-01

    p75NTR, a member of TNF receptor family, is the low affinity receptor common to several mature neurotrophins and the high affinity receptor for pro-neurotrophins. Brain-Derived Neurotrophic Factor (BDNF), a member of neurotrophin family has been described to play an important role in development and progression of several cancers, through its binding to a high affinity tyrosine kinase receptor B (TrkB) and/or p75NTR. However, the functions of these two receptors in renal cell carcinoma (RCC) have never been investigated. An overexpression of p75NTR, pro-BDNF, and to a lesser extent for TrkB and sortilin, was detected by immunohistochemistry in a cohort of 83 clear cell RCC tumors. p75NTR, mainly expressed in tumor tissues, was significantly associated with higher Fuhrman grade in multivariate analysis. In two derived-RCC lines, 786-O and ACHN cells, we demonstrated that pro-BDNF induced cell survival and migration, through p75NTR as provided by p75NTR RNA silencing or blocking anti-p75NTR antibody. This mechanism is independent of TrkB activation as demonstrated by k252a, a tyrosine kinase inhibitor for Trk neurotrophin receptors. Taken together, these data highlight for the first time an important role for p75NTR in renal cancer and indicate a putative novel target therapy in RCC. PMID:27120782

  18. Modulation of c-Fos and BDNF Protein Expression in Pentylenetetrazole-Kindled Mice following the Treatment with Novel Antiepileptic Compound HHL-6

    Directory of Open Access Journals (Sweden)

    Saima Mahmood Malhi

    2014-01-01

    Full Text Available Brain-derived neurotrophic factor (BDNF and c-Fos are shown to promote epileptogenesis and are taken as a marker of neuronal activity. The present study investigated the expression of BDNF and c-Fos in mice brain with pentylenetetrazol- (PTZ- induced generalized seizure and evaluated the effect of novel tryptamine derivative HHL-6 on the expression of these two markers. The subconvulsive dose of PTZ (50 mg/kg was administered on alternate days in the experimental groups until the seizure scores 4-5 developed in the PTZ-control group. At the end of each experiment, animals were sacrificed, brain samples were collected and cryosectioned, and immunohistochemical analysis of BDNF and c-Fos protein was performed. Data obtained from two sections per mouse (n=12 animals/group is presented as means ± S.E.M. The test compound HHL-6 demonstrated a potent anticonvulsant activity in the PTZ-induced seizure in mice. Significant reduction in the BDNF (P<0.003 and c-Fos (P<0.01 protein expression was observed in the HHL-6 treated group. Based on these results we suggest that one of the possible mechanisms of HHL-6 to inhibit epileptogenesis might be due to its controlling effect on the cellular and molecular expression of the factors that contribute to the development of epileptogenic plasticity in the CNS.

  19. FABRICATION AND BIOCOMPATIBILITY OF CELL OUTER MEMBRANE MIMETIC SURFACES

    Institute of Scientific and Technical Information of China (English)

    Ming-ming Zong; Yong-kuan Gong

    2011-01-01

    The surface design used for improving biocompatibility is one of the most important issues for the fabrication of medical devices. For mimicking the ideal surface structure of cell outer membrane, a large number of polymers bearing phosphorylcholine (PC) groups have been employed to modify the surfaces of biomaterials and medical devices. It has been demonstrated that the biocompatibility of the modified materials whose surface is required to interact with a living organism has been obviously improved by introducing PC groups. In this review, the fabrication strategies of cell outer membrane mimetic surfaces and their resulted biocompatibilities were summarized.

  20. Mimetic Finite Differences for Flow in Fractures from Microseismic Data

    KAUST Repository

    Al-Hinai, Omar

    2015-01-01

    We present a method for porous media flow in the presence of complex fracture networks. The approach uses the Mimetic Finite Difference method (MFD) and takes advantage of MFD\\'s ability to solve over a general set of polyhedral cells. This flexibility is used to mesh fracture intersections in two and three-dimensional settings without creating small cells at the intersection point. We also demonstrate how to use general polyhedra for embedding fracture boundaries in the reservoir domain. The target application is representing fracture networks inferred from microseismic analysis.

  1. Mimetic discretization of two-dimensional magnetic diffusion equations

    Science.gov (United States)

    Lipnikov, Konstantin; Reynolds, James; Nelson, Eric

    2013-08-01

    In case of non-constant resistivity, cylindrical coordinates, and highly distorted polygonal meshes, a consistent discretization of the magnetic diffusion equations requires new discretization tools based on a discrete vector and tensor calculus. We developed a new discretization method using the mimetic finite difference framework. It is second-order accurate on arbitrary polygonal meshes and a consistent calculation of the Joule heating is intrinsic within it. The second-order convergence rates in L2 and L1 norms were verified with numerical experiments.

  2. Glucocorticoids modulate BDNF mRNA expression in the rat hippocampus after traumatic brain injury.

    Science.gov (United States)

    Grundy, P L; Patel, N; Harbuz, M S; Lightman, S L; Sharples, P M

    2000-10-20

    Brain-derived neurotrophic factor (BDNF) expression in rat hippocampus is increased after experimental traumatic brain injury (TBI) and may be neuroprotective. Glucocorticoids are important regulators of brain neurotrophin levels and are often prescribed following TBI. The effect of adrenalectomy (ADX) on the expression of BDNF mRNA in the hippocampus after TBI has not been investigated to date. We used fluid percussion injury (FPI) and in situ hybridization to evaluate the expression of BDNF mRNA in the hippocampus 4 h after TBI in adrenal-intact or adrenalectomized rats (with or without corticosterone replacement). FPI and ADX independently increased expression of BDNF mRNA. In animals undergoing FPI, prior ADX caused further elevation of BDNF mRNA and this upregulation was prevented by corticosterone replacement in ADX rats. These findings suggest that glucocorticoids are involved in the modulation of the BDNF mRNA response to TBI.

  3. Prefrontal cortical BDNF: A regulatory key in cocaine- and food-reinforced behaviors.

    Science.gov (United States)

    Pitts, Elizabeth G; Taylor, Jane R; Gourley, Shannon L

    2016-07-01

    Brain-derived neurotrophic factor (BDNF) affects synaptic plasticity and neural structure and plays key roles in learning and memory processes. Recent evidence also points to important, yet complex, roles for BDNF in rodent models of cocaine abuse and addiction. Here we examine the role of prefrontal cortical (PFC) BDNF in reward-related decision making and behavioral sensitivity to, and responding for, cocaine. We focus on BDNF within the medial and orbital PFC, its regulation by cocaine during early postnatal development and in adulthood, and how BDNF in turn influences responding for drug reinforcement, including in reinstatement models. When relevant, we draw comparisons and contrasts with experiments using natural (food) reinforcers. We also summarize findings supporting, or refuting, the possibility that BDNF in the medial and orbital PFC regulate the development and maintenance of stimulus-response habits. Further investigation could assist in the development of novel treatment approaches for cocaine use disorders. PMID:26923993

  4. Whole blood BDNF levels in healthy twins discordant for affective disorder

    DEFF Research Database (Denmark)

    Trajkovska, Viktorija; Vinberg, Maj; Aznar, Susana;

    2008-01-01

    BACKGROUND: Depression has been associated with decreased blood BDNF concentrations; but it is unclear if low blood BDNF levels are a state or a trait marker of depression. METHODS: We investigated blood BDNF concentrations in a twin population including both subjects highly predisposed...... and protected against affective disorder. Whole blood assessed for BDNF concentrations and correlated to risk status, neuroticism, and number of stressful life events. RESULTS: Between the groups, we found no significant difference in whole blood BDNF levels. Women at high-risk for depression who had...... experienced three or more recent stressful events (n=26) had decreased whole blood BDNF levels compared to high-risk women with two or less recent stressful events (n=35), 21.6+/-7.0 vs. 18.5+/-4.1 ng/ml, respectively, (p

  5. Depression, the Val66Met polymorphism, age, and gender influence the serum BDNF level

    DEFF Research Database (Denmark)

    Elfving, Betina; Buttenschøn, Henriette Nørmølle; Foldager, Leslie;

    2012-01-01

    Brain-derived neurotrophic factor (BDNF) has been suggested as a candidate gene for depression and numerous studies have investigated the possible association between genetic variants within BDNF and depression. Clinical studies have investigated the serum BDNF levels in individuals with depression....... However, few studies have combined genetic association studies with serum BDNF measurements. The purpose of the present study was therefore to perform an investigation of BDNF using 162 individuals with depression and 289 healthy individuals. All individuals returned a completed questionnaire...... and participated in a semi-structured diagnostic interview. The major contribution of the present study is the integration of clinical assessment of cases and control individuals, simultaneous analyses of several genetic variants, serum BDNF measurements, and information on socio-demographic variables, lifestyle...

  6. [BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF): NEUROBIOLOGY AND MARKER VALUE IN NEUROPSYCHIATRY].

    Science.gov (United States)

    Levada, O A; Cherednichenko, N V

    2015-01-01

    In this review current publications about neurobiology and marker value of brain derived neurotrophic factor (BDNF) in neuropsychiatry are analyzed. It is shown that BDNF is an important member of the family of neurotrophins which widely represented in various structures of the CNS. In prenatal period BDNF is involved in all stages of neuronal networks formation, and in the postnatal period its main role is maintaining the normal brain architectonics, involvement in the processes of neurogenesis and realization of neuroprotective functions. BDNF plays an important role in learning and memory organization, food and motor behavior. BDNF brain expression decreases with age, as well as in degenerative and vascular dementias, affective, anxiety, and behavioral disorders. The reducing of BDNF serum, level reflects the decreasing of its cerebral expression and could be used as a neurobiological marker of these pathological processes but the rising of its concentration could indicate the therapy effectiveness.

  7. Brain-derived neurotrophic factor is produced by skeletal muscle cells in response to contraction and enhances fat oxidation via activation of AMP-activated protein kinase

    DEFF Research Database (Denmark)

    Matthews, V B; Åström, Maj-Brit; Chan, M H S;

    2009-01-01

    AIMS/HYPOTHESIS: Brain-derived neurotrophic factor (BDNF) is produced in skeletal muscle, but its functional significance is unknown. We aimed to determine the signalling processes and metabolic actions of BDNF. METHODS: We first examined whether exercise induced BDNF expression in humans. Next, C2......C12 skeletal muscle cells were electrically stimulated to mimic contraction. L6 myotubes and isolated rat extensor digitorum longus muscles were treated with BDNF and phosphorylation of the proteins AMP-activated protein kinase (AMPK) (Thr(172)) and acetyl coenzyme A carboxylase beta (ACCbeta) (Ser......(79)) were analysed, as was fatty acid oxidation (FAO). Finally, we electroporated a Bdnf vector into the tibialis cranialis muscle of mice. RESULTS: BDNF mRNA and protein expression were increased in human skeletal muscle after exercise, but muscle-derived BDNF appeared not to be released...

  8. BDNF promoter methylation and genetic variation in late-life depression

    OpenAIRE

    Januar, V; Ancelin, M-L; Ritchie, K.; Saffery, R.; Ryan, J

    2015-01-01

    The regulation of the brain-derived neurotrophic factor (BDNF) is important for depression pathophysiology and epigenetic regulation of the BDNF gene may be involved. This study investigated whether BDNF methylation is a marker of depression. One thousand and twenty-four participants were recruited as part of a longitudinal study of psychiatric disorders in general population elderly (age⩾65). Clinical levels of depression were assessed using the Mini International Neuropsychiatric Interview ...

  9. GABAA Receptor Blockade Enhances Memory Consolidation by Increasing Hippocampal BDNF Levels

    OpenAIRE

    Kim, Dong hyun; Kim, Jong Min; Park, Se Jin; Cai, MuDan; Liu, Xiaotong; Lee, Seungheon; Shin, Chan Young; Ryu, Jong Hoon

    2011-01-01

    Memory consolidation is the process by which acquired information is converted to something concrete to be retrieved later. Here we examined a potential role for brain-derived neurotrophic factor (BDNF) in mediating the enhanced memory consolidation induced by the GABAA receptor antagonist, bicuculline methiodide. With the administration of an acquisition trial in naïve mice using a passive avoidance task, mature BDNF (mBDNF) levels were temporally changed in the hippocampal CA1 region, and t...

  10. BDNF Val66Met is Associated with Introversion and Interacts with 5-HTTLPR to Influence Neuroticism

    OpenAIRE

    Terracciano, Antonio; Tanaka, Toshiko; Sutin, Angelina R.; Deiana, Barbara; Balaci, Lenuta; Sanna, Serena; Olla, Nazario; Maschio, Andrea; Uda, Manuela; Ferrucci, Luigi; Schlessinger, David; Costa, Paul T.

    2009-01-01

    Brain-derived neurotrophic factor (BDNF) regulates synaptic plasticity and neurotransmission, and has been linked to neuroticism, a major risk factor for psychiatric disorders. A recent genome-wide association (GWA) scan, however, found the BDNF Val66Met polymorphism (rs6265) associated with extraversion but not with neuroticism. In this study, we examine the links between BDNF and personality traits, assessed using the Revised NEO Personality Inventory (NEO-PI-R), in a sample from SardiNIA (...

  11. BDNF-secreting capsule exerts neuroprotective effects on epilepsy model of rats.

    Science.gov (United States)

    Kuramoto, Satoshi; Yasuhara, Takao; Agari, Takashi; Kondo, Akihiko; Jing, Meng; Kikuchi, Yoichiro; Shinko, Aiko; Wakamori, Takaaki; Kameda, Masahiro; Wang, Feifei; Kin, Kyohei; Edahiro, Satoru; Miyoshi, Yasuyuki; Date, Isao

    2011-01-12

    Brain-derived neurotrophic factor (BDNF) is a well neurotrophic factor with neuroprotective potentials for various diseases in the central nervous system. However several previous studies demonstrated that BDNF might deteriorate symptoms for epilepsy model of animals by progression of abnormal neurogenesis. We hypothesized that continuous administration of BDNF at low dose might be more effective for epilepsy model of animals because high dose of BDNF was used in many studies. BDNF-secreting cells were genetically made and encapsulated for transplantation. Rats receiving BDNF capsule showed significant amelioration of seizure stage and reduction of the number of abnormal spikes at 7 days after kainic acid administration, compared to those of control group. The number of BrdU and BrdU/doublecortin positive cells in the hippocampus of BDNF group significantly increased, compared to that of control group. NeuN positive cells in the CA1 and CA3 of BDNF group were significantly preserved, compared to control group. In conclusion, low dose administration using encapsulated BDNF-secreting cells exerted neuroprotective effects with enhanced neurogenesis on epilepsy model of rats. These results might suggest the importance of the dose and administrative way of this neurotrophic factor to the epilepsy model of animals.

  12. Chronic BDNF deficiency leads to an age-dependent impairment in spatial learning.

    Science.gov (United States)

    Petzold, Anne; Psotta, Laura; Brigadski, Tanja; Endres, Thomas; Lessmann, Volkmar

    2015-04-01

    Brain-derived neurotrophic factor (BDNF) is a crucial mediator of neural plasticity and, consequently, of memory formation. In hippocampus-dependent learning tasks BDNF also seems to play an essential role. However, there are conflicting results concerning the spatial learning ability of aging BDNF(+/-) mice in the Morris water maze paradigm. To evaluate the effect of chronic BDNF deficiency in the hippocampus on spatial learning throughout life, we conducted a comprehensive study to test differently aged BDNF(+/-) mice and their wild type littermates in the Morris water maze and to subsequently quantify their hippocampal BDNF protein levels as well as expression levels of TrkB receptors. We observed an age-dependent learning deficit in BDNF(+/-) animals, starting at seven months of age, despite stable hippocampal BDNF protein expression and continual decline of TrkB receptor expression throughout aging. Furthermore, we detected a positive correlation between hippocampal BDNF protein levels and learning performance during the probe trial in animals that showed a good learning performance during the long-term memory test.

  13. APATHY AND APOE4 ARE ASSOCIATED WITH REDUCED BDNF LEVELS IN ALZHEIMER’S DISEASE

    Science.gov (United States)

    Álvarez, Antón; Aleixandre, Manuel; Linares, Carlos; Masliah, Eliezer; Moessler, Herbert

    2016-01-01

    Reduced brain-derived neurotrophic factor (BDNF) signaling is considered as a pathogenic event in early Alzheimer’s disease (AD), but the influence of apathy and apolipoprotein E epsilon-4 allele (APOE4) on serum BDNF values was not previously investigated in AD. We evaluated serum BDNF levels in AD, amnestic mild cognitive impairment (MCI) and control subjects. Baseline BDNF levels were similar in AD, MCI and controls. AD patients having apathy showed lower BDNF values than patients without apathy (p<0.05). After correction for the influence of apathy, APOE4 carriers showed lower BDNF levels (p<0.01) and MMSE scores (p<0.01) than non-APOE4 carriers in the subgroup of AD females, but not in males. Significant (p<0.05) positive correlations between BDNF values and MMSE scores were only observed in subgroups of AD males and of AD patients without apathy. These results are showing the association of apathy and APOE4 with reduced serum BDNF levels in AD, and are suggesting that BDNF reductions might contribute to the worse cognitive performance exhibited by AD apathetic patients and female APOE4 carriers. PMID:25024337

  14. BDNF/TrkB signaling protects HT-29 human colon cancer cells from EGFR inhibition

    International Nuclear Information System (INIS)

    Highlights: ► BDNF protected HT-29 colorectal cancer cells from the antitumor effect of cetuximab. ► TrkB inhibition potentiated the antitumor effect of cetuximab. ► BDNF/TrkB signaling might be involved in resistance to anti-EGFR therapy. -- Abstract: The clinical success of targeted treatment of colorectal cancer (CRC) is often limited by resistance to anti-epidermal growth factor receptor (EGFR) therapy. The neurotrophin brain-derived neurotrophic factor (BDNF) and its receptor TrkB have recently emerged as anticancer targets, and we have previously shown increased BDNF levels in CRC tumor samples. Here we report the findings from in vitro experiments suggesting that BDNF/TrkB signaling can protect CRC cells from the antitumor effects of EGFR blockade. The anti-EGFR monoclonal antibody cetuximab reduced both cell proliferation and the mRNA expression of BDNF and TrkB in human HT-29 CRC cells. The inhibitory effect of cetuximab on cell proliferation and survival was counteracted by the addition of human recombinant BDNF. Finally, the Trk inhibitor K252a synergistically enhanced the effect of cetuximab on cell proliferation, and this effect was blocked by BDNF. These results provide the first evidence that increased BDNF/TrkB signaling might play a role in resistance to EGFR blockade. Moreover, it is possible that targeting TrkB could potentiate the anticancer effects of anti-EGFR therapy.

  15. BDNF genetic variants are associated with onset age of familial Parkinson disease: GenePD Study.

    Science.gov (United States)

    Karamohamed, S; Latourelle, J C; Racette, B A; Perlmutter, J S; Wooten, G F; Lew, M; Klein, C; Shill, H; Golbe, L I; Mark, M H; Guttman, M; Nicholson, G; Wilk, J B; Saint-Hilaire, M; DeStefano, A L; Prakash, R; Tobin, S; Williamson, J; Suchowersky, O; Labell, N; Growdon, B N J; Singer, C; Watts, R; Goldwurm, S; Pezzoli, G; Baker, K B; Giroux, M L; Pramstaller, P P; Burn, D J; Chinnery, P; Sherman, S; Vieregge, P; Litvan, I; Gusella, J F; Myers, R H; Parsian, A

    2005-12-13

    Brain-derived neurotrophic factor (BDNF) stimulates neuronal growth and protects nigral dopamine neurons in animal models of Parkinson disease (PD). Therefore, BDNF is a candidate gene for PD. The authors investigated five single-nucleotide polymorphisms in 597 cases of familial PD. Homozygosity for the rare allele of the functional BDNF G196A (Val66Met) variant was associated with a 5.3-year older onset age (p = 0.0001). These findings suggest that BDNF may influence PD onset age. PMID:16344533

  16. BDNF/TrkB signaling protects HT-29 human colon cancer cells from EGFR inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Brunetto de Farias, Caroline [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Children' s Cancer Institute, 90420-140 Porto Alegre, RS (Brazil); Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, 90050-170 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Heinen, Tiago Elias; Pereira dos Santos, Rafael [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, 90050-170 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Abujamra, Ana Lucia [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); Children' s Cancer Institute, 90420-140 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Schwartsmann, Gilberto [Cancer Research Laboratory, University Hospital Research Center (CPE-HCPA), Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); National Institute for Translational Medicine (INCT-TM), 90035-003 Porto Alegre, RS (Brazil); Department of Internal Medicine, School of Medicine, Federal University of Rio Grande do Sul, 90035-003 Porto Alegre, RS (Brazil); and others

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer BDNF protected HT-29 colorectal cancer cells from the antitumor effect of cetuximab. Black-Right-Pointing-Pointer TrkB inhibition potentiated the antitumor effect of cetuximab. Black-Right-Pointing-Pointer BDNF/TrkB signaling might be involved in resistance to anti-EGFR therapy. -- Abstract: The clinical success of targeted treatment of colorectal cancer (CRC) is often limited by resistance to anti-epidermal growth factor receptor (EGFR) therapy. The neurotrophin brain-derived neurotrophic factor (BDNF) and its receptor TrkB have recently emerged as anticancer targets, and we have previously shown increased BDNF levels in CRC tumor samples. Here we report the findings from in vitro experiments suggesting that BDNF/TrkB signaling can protect CRC cells from the antitumor effects of EGFR blockade. The anti-EGFR monoclonal antibody cetuximab reduced both cell proliferation and the mRNA expression of BDNF and TrkB in human HT-29 CRC cells. The inhibitory effect of cetuximab on cell proliferation and survival was counteracted by the addition of human recombinant BDNF. Finally, the Trk inhibitor K252a synergistically enhanced the effect of cetuximab on cell proliferation, and this effect was blocked by BDNF. These results provide the first evidence that increased BDNF/TrkB signaling might play a role in resistance to EGFR blockade. Moreover, it is possible that targeting TrkB could potentiate the anticancer effects of anti-EGFR therapy.

  17. BDNF表达下调抑制HepG2细胞侵袭的相关分子机制研究%Down-regulation of BDNF suppressed invasion of HepG2 cells and associated molecular mechanisms

    Institute of Scientific and Technical Information of China (English)

    郭大伟; 侯学忠; 孙文郁; 朱磊; 张弘彬; 姜晓峰; 梁健

    2012-01-01

    Objective: To investigate the effects of siRNA specificly for BDNF on apoptosis and invasion of HepG2 cells and its potential molecular mechanism. Methods; The expression of BDNF in cells was examined by western blot and BDNF secretion was evaluated by ELISA in human HCC cell lines of HepG2. BDNF knockdown was performed by specific BDNF - siRNA transfection in HepG2 cells, actin cytoskelelon was shown by FITC - phalloidin staining and the activations of RhoA, Racl or Cdc42 were determined by Western blot. Cell apoptosis and invasion were examined by flow cytometry and transwell assay respectively. Results: The expression of BDNF was found in HepG2 cells. BDNF concentration in the supernatant of HepG2 cells was 88.56 ±7.45 pg/ml. Inhibited expression of BDNF by specific siRNA showed impaired actin polymerization and decreased activations of RhoA or Racl in HepG2 cells. BDNF knockdown also induced apoptosis and suppressed invasion of HepG2 cells. Conclusion: BDNF knockdown inhibited cell invasion probably through the blocked actin polymerization and the correlated inactivation of RhoA or Racl. Aiming at BDNF/TrkB signaling interruption may be an effective strategy to prevent HCC progression.%目的:应用特异性siRNA下调HepG2细胞中BDNF表达,观察对细胞凋亡和侵袭的影响并探讨相关分子机制.方法:在人HCC细胞系HepG2中,采用Western blot方法检测BDNF的表达,采用ELISA方法检测培养液上清BDNF的分泌水平.特异性BDNF-siRNA转染细胞,采用FITC-phalloidin染色方法检测actin 细胞骨架的变化,采用Western blot方法检测细胞内RhoA、Rac1、Cdc42的活化情况.同时,流式细胞术检测细胞凋亡,Transwell小室测定细胞侵袭能力的变化.结果:HepG2细胞培养上清中BDNF含量为88.56±7.45 pg/ml.在HepG2细胞中,特异性BDNF-siRNA显著抑制BDNF的表达,干扰细胞内actin细胞骨架聚合,RhoA或Racl活性受到抑制,同时凋亡细胞数增加、细胞侵袭能力下降.结论:干

  18. The mimetic repertoire of the spotted bowerbird Ptilonorhynchus maculatus

    Science.gov (United States)

    Kelley, Laura A.; Healy, Susan D.

    2011-06-01

    Although vocal mimicry in songbirds is well documented, little is known about the function of such mimicry. One possibility is that the mimic produces the vocalisations of predatory or aggressive species to deter potential predators or competitors. Alternatively, these sounds may be learned in error as a result of their acoustic properties such as structural simplicity. We determined the mimetic repertoires of a population of male spotted bowerbirds Ptilonorhynchus maculatus, a species that mimics predatory and aggressive species. Although male mimetic repertoires contained an overabundance of vocalisations produced by species that were generally aggressive, there was also a marked prevalence of mimicry of sounds that are associated with alarm such as predator calls, alarm calls and mobbing calls, irrespective of whether the species being mimicked was aggressive or not. We propose that it may be the alarming context in which these sounds are first heard that may lead both to their acquisition and to their later reproduction. We suggest that enhanced learning capability during acute stress may explain vocal mimicry in many species that mimic sounds associated with alarm.

  19. Exposure to music in the perinatal period enhances learning performance and alters BDNF/TrkB signaling in mice as adults.

    Science.gov (United States)

    Chikahisa, Sachiko; Sei, Hiroyoshi; Morishima, Masaki; Sano, Atsuko; Kitaoka, Kazuyoshi; Nakaya, Yutaka; Morita, Yusuke

    2006-05-15

    Music has been suggested to have a beneficial effect on various types of performance in humans. However, the physiological and molecular mechanism of this effect remains unclear. We examined the effect of music exposure during the perinatal period on learning behavior in adult mice, and measured the levels of brain-derived neurotrophic factor (BDNF) and its receptor, tyrosine kinase receptor B (TrkB), which play critical roles in synaptic plasticity. In addition, we measured the levels of 3-phosphoinositide-dependent protein kinase-1 (PDK1) and mitogen-activated protein kinase (MAPK), downstream targets of two main pathways in BDNF/TrkB signaling. Music-exposed mice completed a maze learning task with fewer errors than the white noise-exposed mice and had lower levels of BDNF and higher levels of TrkB and PDK1 in the cortex. MAPK levels were unchanged. Furthermore, TrkB and PDK1 protein levels in the cortex showed a significant negative correlation with the number of errors on the maze. These results suggest that perinatal exposure of mice to music has an influence on BDNF/TrkB signaling and its intracellular signaling pathway targets, including PDK1, and thus may induce improved learning and memory functions.

  20. Maternal Exercise during Pregnancy Increases BDNF Levels and Cell Numbers in the Hippocampal Formation but Not in the Cerebral Cortex of Adult Rat Offspring.

    Directory of Open Access Journals (Sweden)

    Sérgio Gomes da Silva

    Full Text Available Clinical evidence has shown that physical exercise during pregnancy may alter brain development and improve cognitive function of offspring. However, the mechanisms through which maternal exercise might promote such effects are not well understood. The present study examined levels of brain-derived neurotrophic factor (BDNF and absolute cell numbers in the hippocampal formation and cerebral cortex of rat pups born from mothers exercised during pregnancy. Additionally, we evaluated the cognitive abilities of adult offspring in different behavioral paradigms (exploratory activity and habituation in open field tests, spatial memory in a water maze test, and aversive memory in a step-down inhibitory avoidance task. Results showed that maternal exercise during pregnancy increased BDNF levels and absolute numbers of neuronal and non-neuronal cells in the hippocampal formation of offspring. No differences in BDNF levels or cell numbers were detected in the cerebral cortex. It was also observed that offspring from exercised mothers exhibited better cognitive performance in nonassociative (habituation and associative (spatial learning mnemonic tasks than did offspring from sedentary mothers. Our findings indicate that maternal exercise during pregnancy enhances offspring cognitive function (habituation behavior and spatial learning and increases BDNF levels and cell numbers in the hippocampal formation of offspring.

  1. Inhibition of Salmonella enterica biofilm formation using small-molecule adenosine mimetics.

    Science.gov (United States)

    Koopman, Jacob A; Marshall, Joanna M; Bhatiya, Aditi; Eguale, Tadesse; Kwiek, Jesse J; Gunn, John S

    2015-01-01

    Biofilms have been widely implicated in chronic infections and environmental persistence of Salmonella enterica, facilitating enhanced colonization of surfaces and increasing the ability of the bacteria to be transmitted to new hosts. Salmonella enterica serovar Typhi biofilm formation on gallstones from humans and mice enhances gallbladder colonization and bacterial shedding, while Salmonella enterica serovar Typhimurium biofilms facilitate long-term persistence in a number of environments important to food, medical, and farming industries. Salmonella regulates expression of many virulence- and biofilm-related processes using kinase-driven pathways. Kinases play pivotal roles in phosphorylation and energy transfer in cellular processes and possess an ATP-binding pocket required for their functions. Many other cellular proteins also require ATP for their activity. Here we test the hypothesis that pharmacological interference with ATP-requiring enzymes utilizing adenosine mimetic compounds would decrease or inhibit bacterial biofilm formation. Through the screening of a 3,000-member ATP mimetic library, we identified a single compound (compound 7955004) capable of significantly reducing biofilm formation by S. Typhimurium and S. Typhi. The compound was not bactericidal or bacteriostatic toward S. Typhimurium or cytotoxic to mammalian cells. An ATP-Sepharose affinity matrix technique was used to discover potential protein-binding targets of the compound and identified GroEL and DeoD. Compound 7955004 was screened against other known biofilm-forming bacterial species and was found to potently inhibit biofilms of Acinetobacter baumannii as well. The identification of a lead compound with biofilm-inhibiting capabilities toward Salmonella provides a potential new avenue of therapeutic intervention against Salmonella biofilm formation, with applicability to biofilms of other bacterial pathogens.

  2. Rapid and long-term induction of effector immediate early genes (BDNF, Neuritin and Arc) in peri-infarct cortex and dentate gyrus after ischemic injury in rat brain

    DEFF Research Database (Denmark)

    Rickhag, Karl Mattias; Teilum, Maria; Wieloch, Tadeusz

    2007-01-01

    including cerebral cortex and hippocampus. Brain-derived neurotrophic factor (BDNF), Neuritin and Activity-regulated cytoskeleton-associated protein (Arc) belong to a subgroup of immediate early genes implicated in synaptic plasticity known as effector immediate early genes. Here, we investigated...... at 0-6 h of reperfusion for Neuritin and 0-12 h of reperfusion for Arc while BDNF was induced 0-9 h of reperfusion. Our study demonstrates a rapid and long-term activation of effector immediate early genes in distinct brain areas following ischemic injury in rat. Effector gene activation may be part...

  3. The requirement of BDNF for hippocampal synaptic plasticity is experience‐dependent

    Science.gov (United States)

    Aarse, Janna; Herlitze, Stefan

    2016-01-01

    ABSTRACT Brain‐derived neurotrophic factor (BDNF) supports neuronal survival, growth, and differentiation and has been implicated in forms of hippocampus‐dependent learning. In vitro, a specific role in hippocampal synaptic plasticity has been described, although not all experience‐dependent forms of synaptic plasticity critically depend on BDNF. Synaptic plasticity is likely to enable long‐term synaptic information storage and memory, and the induction of persistent (>24 h) forms, such as long‐term potentiation (LTP) and long‐term depression (LTD) is tightly associated with learning specific aspects of a spatial representation. Whether BDNF is required for persistent (>24 h) forms of LTP and LTD, and how it contributes to synaptic plasticity in the freely behaving rodent has never been explored. We examined LTP, LTD, and related forms of learning in the CA1 region of freely dependent mice that have a partial knockdown of BDNF (BDNF+/−). We show that whereas early‐LTD (BDNF, short‐term depression (BDNF is required for LTP that is induced by mild, but not strong short afferent stimulation protocols. Object‐place learning triggers LTD in the CA1 region of mice. We observed that object‐place memory was impaired and the object‐place exploration failed to induce LTD in BDNF+/− mice. Furthermore, spatial reference memory, that is believed to be enabled by LTP, was also impaired. Taken together, these data indicate that BDNF is required for specific, but not all, forms of hippocampal‐dependent information storage and memory. Thus, very robust forms of synaptic plasticity may circumvent the need for BDNF, rather it may play a specific role in the optimization of weaker forms of plasticity. The finding that both learning‐facilitated LTD and spatial reference memory are both impaired in BDNF+/− mice, suggests moreover, that it is critically required for the physiological encoding of hippocampus‐dependent memory. © 2015 The Authors

  4. Sulfated levan from Halomonas smyrnensis as a bioactive, heparin-mimetic glycan for cardiac tissue engineering applications.

    Science.gov (United States)

    Erginer, Merve; Akcay, Ayca; Coskunkan, Binnaz; Morova, Tunc; Rende, Deniz; Bucak, Seyda; Baysal, Nihat; Ozisik, Rahmi; Eroglu, Mehmet S; Agirbasli, Mehmet; Toksoy Oner, Ebru

    2016-09-20

    Chemical derivatives of levan from Halomonas smyrnensis AAD6(T) with low, medium and high levels of sulfation were synthesized and characterized by FTIR and 2D-NMR. Sulfated levan samples were found to exhibit anticoagulation activity via the intrinsic pathway like heparin in a dose-dependent manner. Exceptionally high heparin equivalent activity of levan sulfate was shown to proceed via thrombin inhibition where decreased Factor Xa activity with increasing concentration was observed in antithrombin tests and above a certain concentration, levan sulfate showed a better inhibitor activity than heparin. In vitro experimental results were then verified in silico by docking studies using equilibrium structures obtained by molecular dynamic simulations and results suggested a sulfation dependent binding mechanism. With its high biocompatibility and heparin mimetic activity, levan sulfate can be considered as a suitable functional biomaterial to design biologically active, functionalized, thin films and engineered smart scaffolds for cardiac tissue engineering applications. PMID:27261753

  5. Plasma levels of mature brain-derived neurotrophic factor (BDNF) and matrix metalloproteinase-9 (MMP-9) in treatment-resistant schizophrenia treated with clozapine.

    Science.gov (United States)

    Yamamori, Hidenaga; Hashimoto, Ryota; Ishima, Tamaki; Kishi, Fukuko; Yasuda, Yuka; Ohi, Kazutaka; Fujimoto, Michiko; Umeda-Yano, Satomi; Ito, Akira; Hashimoto, Kenji; Takeda, Masatoshi

    2013-11-27

    Brain-derived neurotrophic factor (BDNF) regulates the survival and growth of neurons, and influences synaptic efficiency and plasticity. Peripheral BDNF levels in patients with schizophrenia have been widely reported in the literature. However, it is still controversial whether peripheral levels of BDNF are altered in patients with schizophrenia. The peripheral BDNF levels previously reported in patients with schizophrenia were total BDNF (proBDNF and mature BDNF) as it was unable to specifically measure mature BDNF due to limited BDNF antibody specificity. In this study, we examined whether peripheral levels of mature BDNF were altered in patients with treatment-resistant schizophrenia. Matrix metalloproteinase-9 (MMP-9) levels were also measured, as MMP-9 plays a role in the conversion of proBDNF to mature BDNF. Twenty-two patients with treatment-resistant schizophrenia treated with clozapine and 22 age- and sex-matched healthy controls were enrolled. The plasma levels of mature BDNF and MMP-9 were measured using ELISA kits. No significant difference was observed for mature BDNF however, MMP-9 was significantly increased in patients with schizophrenia. The significant correlation was observed between mature BDNF and MMP-9 plasma levels. Neither mature BDNF nor MMP-9 plasma levels were associated clinical variables. Our results do not support the view that peripheral BDNF levels are associated with schizophrenia. MMP-9 may play a role in the pathophysiology of schizophrenia and serve as a biomarker for schizophrenia.

  6. BDNF mediates improvements in executive function following a 1-year exercise intervention

    Directory of Open Access Journals (Sweden)

    Regina Lynn Leckie

    2014-12-01

    Full Text Available Executive function declines with age, but engaging in aerobic exercise may attenuate decline. One mechanism by which aerobic exercise may preserve executive function is through the up-regulation of brain-derived neurotropic factor (BDNF, which also declines with age. The present study examined BDNF as a mediator of the effects of a 1-year walking intervention on executive function in 90 older adults (mean age = 66.82. Participants were randomized to a stretching and toning control group or a moderate intensity walking intervention group. BDNF serum levels and performance on a task-switching paradigm were collected at baseline and follow-up. We found that age moderated the effect of intervention group on changes in BDNF levels, with those in the highest age quartile showing the greatest increase in BDNF after 1-year of moderate intensity walking exercise (p = .036. The mediation analyses revealed that BDNF mediated the effect of the intervention on task-switch accuracy, but did so as a function of age, such that exercise-induced changes in BDNF mediated the effect of exercise on task-switch performance only for individuals over the age of 71. These results demonstrate that both age and BDNF serum levels are important factors to consider when investigating the mechanisms by which exercise interventions influence cognitive outcomes, particularly in elderly populations.

  7. Investigating the Role of Hippocampal BDNF in Anxiety Vulnerability Using Classical Eyeblink Conditioning.

    Science.gov (United States)

    Janke, Kellie L; Cominski, Tara P; Kuzhikandathil, Eldo V; Servatius, Richard J; Pang, Kevin C H

    2015-01-01

    Dysregulation of brain-derived neurotrophic factor (BDNF), behavioral inhibition temperament (BI), and small hippocampal volume have been linked to anxiety disorders. Individuals with BI show facilitated acquisition of the classically conditioned eyeblink response (CCER) as compared to non-BI individuals, and a similar pattern is seen in an animal model of BI, the Wistar-Kyoto (WKY) rat. The present study examined the role of hippocampal BDNF in the facilitated delay CCER of WKY rats. Consistent with earlier work, acquisition was facilitated in WKY rats compared to the Sprague Dawley (SD) rats. Facilitated acquisition was associated with increased BDNF, TrkB, and Arc mRNA in the dentate gyrus of SD rats, but learning-induced increases in BDNF and Arc mRNA were significantly smaller in WKY rats. To determine whether reduced hippocampal BDNF in WKY rats was a contributing factor for their facilitated CCER, BDNF or saline infusions were given bilaterally into the dentate gyrus region 1 h prior to training. BDNF infusion did not alter the acquisition of SD rats, but significantly dampened the acquisition of CCER in the WKY rats, such that acquisition was similar to SD rats. Together, these results suggest that inherent differences in the BDNF system play a critical role in the facilitated associative learning exhibited by WKY rats, and potentially individuals with BI. Facilitated associative learning may represent a vulnerability factor in the development of anxiety disorders.

  8. BDNF mediates improvements in executive function following a 1-year exercise intervention.

    Science.gov (United States)

    Leckie, Regina L; Oberlin, Lauren E; Voss, Michelle W; Prakash, Ruchika S; Szabo-Reed, Amanda; Chaddock-Heyman, Laura; Phillips, Siobhan M; Gothe, Neha P; Mailey, Emily; Vieira-Potter, Victoria J; Martin, Stephen A; Pence, Brandt D; Lin, Mingkuan; Parasuraman, Raja; Greenwood, Pamela M; Fryxell, Karl J; Woods, Jeffrey A; McAuley, Edward; Kramer, Arthur F; Erickson, Kirk I

    2014-01-01

    Executive function declines with age, but engaging in aerobic exercise may attenuate decline. One mechanism by which aerobic exercise may preserve executive function is through the up-regulation of brain-derived neurotropic factor (BDNF), which also declines with age. The present study examined BDNF as a mediator of the effects of a 1-year walking intervention on executive function in 90 older adults (mean age = 66.82). Participants were randomized to a stretching and toning control group or a moderate intensity walking intervention group. BDNF serum levels and performance on a task-switching paradigm were collected at baseline and follow-up. We found that age moderated the effect of intervention group on changes in BDNF levels, with those in the highest age quartile showing the greatest increase in BDNF after 1-year of moderate intensity walking exercise (p = 0.036). The mediation analyses revealed that BDNF mediated the effect of the intervention on task-switch accuracy, but did so as a function of age, such that exercise-induced changes in BDNF mediated the effect of exercise on task-switch performance only for individuals over the age of 71. These results demonstrate that both age and BDNF serum levels are important factors to consider when investigating the mechanisms by which exercise interventions influence cognitive outcomes, particularly in elderly populations. PMID:25566019

  9. A meta-analysis of circulating BDNF concentrations in anorexia nervosa

    NARCIS (Netherlands)

    Brandys, Marek K.; Kas, Martien J. H.; van Elburg, Annemarie A.; Campbell, Iain C.; Adan, Roger A. H.

    2011-01-01

    Objectives. Brain derived neurotrophic factor (BDNF) is involved in neuroplasticity, and in the homeostatic regulation of food intake and energy expenditure. It also has a role in stress responsivity and reward processing. On the basis of its involvement in these various processes, BDNF can be hypot

  10. Role of BDNF in bipolar and unipolar disorder: clinical and theoretical implications.

    Science.gov (United States)

    Post, Robert M

    2007-12-01

    A number of lines of converging evidence suggest that brain-derived neurotrophic factor (BDNF) may play a role in the onset and treatment of bipolar disorder. We review pertinent data on BDNF from several different areas of preclinical and clinical investigation that suggest novel theoretical and treatment implications for the recurrent affective disorders. Data from several recent studies have also converged showing that the val66met allele of BDNF, a common single nucleotide polymorphism (SNP), is associated with selective minor deficits in cognitive functioning in subjects with schizophrenia, bipolar illness, and normal controls. Yet, paradoxically, the better functioning val66val allele of BDNF appears to be associated with an increased risk for bipolar disorder and perhaps early onset or rapid cycling. All the primary antidepressant modalities, as well as the mood stabilizers lithium and valproate, increase BDNF. Stressors decrease BDNF and this effect can be blocked by antidepressants. Serum BDNF is low in proportion to the severity of mania and depression and increases with clinical improvement. Assessment of the val66val BDNF allele and a range of other SNPs as potential vulnerability factors for bipolar illness and its early onset could facilitate studies of early intervention, help reduce long delays between the onset of first symptoms and the first treatment, and help in the prediction of individual patient's likelihood of responding to a given treatment. PMID:17239400

  11. A meta-analysis of circulating BDNF concentrations in anorexia nervosa

    NARCIS (Netherlands)

    Brandys, Marek K; Kas, Martien J H; van Elburg, Annemarie A; Campbell, Iain C; Adan, Roger A H

    2011-01-01

    OBJECTIVES: Brain derived neurotrophic factor (BDNF) is involved in neuroplasticity, and in the homeostatic regulation of food intake and energy expenditure. It also has a role in stress responsivity and reward processing. On the basis of its involvement in these various processes, BDNF can be hypot

  12. BDNF in late-life depression: effect of SSRI usage and interaction with childhood abuse

    NARCIS (Netherlands)

    Meij, A. van der; Comijs, H.C.; Dols, A.; Janzing, J.G.E.; Oude Voshaar, R.C.

    2014-01-01

    Brain-Derived Neurotrophic Factor (BDNF) serum levels are abnormally low in depressed patients as compared to healthy controls and normalize with SSRI treatment. The aim of this study is to examine serum BDNF levels in late-life depression, stratified for SSRI usage, and to explore the relation betw

  13. BDNF in late-life depression : Effect of SSRI usage and interaction with childhood abuse

    NARCIS (Netherlands)

    van der Meij, Annemarie; Comijs, Hannie C.; Dols, Annemieke; Janzing, Joost G. E.; Oude Voshaar, Richard

    2014-01-01

    Brain-Derived Neurotrophic Factor (BDNF) serum levels are abnormally low in depressed patients as compared to healthy controls and normalize with SSRI treatment. The aim of this study is to examine serum BDNF levels in late-life depression, stratified for SSRI usage, and to explore the relation betw

  14. BDNF serum levels are not related to cognitive functioning in older depressed patients and controls

    NARCIS (Netherlands)

    Dols, Annemiek; Thesing, Carisha S.; Bouckaert, Filip; Oude Voshaar, Richard; Comijs, Hannie C.; Stek, M. L.

    2015-01-01

    Background: Depression and cognitive decline are highly prevalent in older persons and both are associated with low serum brain derived neurotrophic factor (BDNF). Mutual pathways of depression and cognitive decline in older persons may explain the overlap in symptoms and low serum BDNF. We hypothes

  15. Age-Dependent Deficits in Fear Learning in Heterozygous BDNF Knock-Out Mice

    Science.gov (United States)

    Endres, Thomas; Lessmann, Volkmar

    2012-01-01

    Beyond its trophic function, the neurotrophin BDNF (brain-derived neurotrophic factor) is well known to crucially mediate synaptic plasticity and memory formation. Whereas recent studies suggested that acute BDNF/TrkB signaling regulates amygdala-dependent fear learning, no impairments of cued fear learning were reported in heterozygous BDNF…

  16. Alternative Splicing Variants and DNA Methylation Status of BDNF in Inbred Chicken Lines

    Science.gov (United States)

    Brain derived neurotrophic factor (BDNF) plays essential roles in neuronal survival and differentiation, synaptic plasticity, central regulation of energy homeostasis, and neuronal development of the central and peripheral nerve system. Here, we report two new splicing variants of the chicken BDNF g...

  17. BDNF serum levels are not related to cognitive functioning in older depressed patients and controls

    NARCIS (Netherlands)

    Dols, A.; Thesing, C.S.; Bouckaert, F.; Oude Voshaar, R.C.; Comijs, H.C.; Stek, M.L.

    2015-01-01

    BACKGROUND: Depression and cognitive decline are highly prevalent in older persons and both are associated with low serum brain derived neurotrophic factor (BDNF). Mutual pathways of depression and cognitive decline in older persons may explain the overlap in symptoms and low serum BDNF. We hypothes

  18. Association between BDNF-rs6265 and obesity in the Boston Puerto Rican Health Study

    Science.gov (United States)

    The objective of this study is to examine a functional variant (rs6265) in the BDNF gene interacting with dietary intake modulate obesity traits in the Boston Puerto Rican Health Study population. BDNF rs6265 was genotyped in 1147 Puerto Ricans (aged 45-75 years), and examined for association with o...

  19. Investigating the role of hippocampal BDNF in anxiety vulnerability using classical eyeblink conditioning

    Directory of Open Access Journals (Sweden)

    Kellie L Janke

    2015-07-01

    Full Text Available Dysregulation of brain-derived neurotrophic factor (BDNF, behavioral inhibition temperament (BI and small hippocampal volume have been linked to anxiety disorders. Individuals with BI show facilitated acquisition of the classically conditioned eyeblink response (CCER as compared to non-BI individuals, and a similar pattern is seen in an animal model of BI, the Wistar-Kyoto (WKY rat. The present study examined the role of hippocampal BDNF in the facilitated delay CCER of WKY rats. Consistent with earlier work, acquisition was facilitated in WKY rats compared to the SD rats. Facilitated acquisition was associated with increased BDNF, TrkB, and Arc mRNA in the dentate gyrus of SD rats, but learning-induced increases in BDNF and Arc mRNA were significantly smaller in WKY rats. To determine if reduced hippocampal BDNF in WKY rats was a contributing factor for their facilitated CCER, BDNF or saline infusions were given bilaterally into the dentate gyrus region one hour prior to training. BDNF infusion did not alter the acquisition of SD rats, but significantly dampened the acquisition of CCER in the WKY rats, such that acquisition was similar to SD rats. Together, these results suggest that inherent differences in the BDNF system play a critical role in the facilitated associative learning exhibited by WKY rats, and potentially individuals with BI. Facilitated associative learning may represent a vulnerability factor in the development of anxiety disorders.

  20. Self-assembly of fibronectin mimetic peptide-amphiphile nanofibers

    Science.gov (United States)

    Rexeisen, Emilie Lynn

    Many therapeutic strategies incorporate peptides into their designs to mimic the natural protein ligands found in vivo. A few examples are the short peptide sequences RGD and PHSRN that mimic the primary and synergy-binding domains of the extracellular matrix protein, fibronectin, which is recognized by the cell surface receptor, alpha5beta 1 integrin. Even though scaffold modification with biomimetic peptides remains one of the most promising approaches for tissue engineering, the use of these peptides in therapeutic tissue-engineered products and drug delivery systems available on the commercial market is limited because the peptides are not easily able to mimic the natural protein. The design of a peptide that can effectively target the alpha5beta1 integrin would greatly increase biomimetic scaffold therapeutic potential. A novel peptide containing both the RGD primary binding domain and PHSRN synergy-binding domain for fibronectin joined with the appropriate linker should bind alpha 5beta1 integrin more efficiently and lead to greater cell adhesion over RGD alone. Several fibronectin mimetic peptides were designed and coupled to dialkyl hydrocarbon tails to make peptide-amphiphiles. The peptides contained different linkers connecting the two binding domains and different spacers separating the hydrophobic tails from the hydrophilic headgroups. The peptide-amphiphiles were deposited on mica substrates using the Langmuir-Blodgett technique. Langmuir isotherms indicated that the peptide-amphiphiles that contained higher numbers of serine residues formed a more tightly packed monolayer, but the increased number of serines also made transferring the amphiphiles to the mica substrate more difficult. Atomic force microscopy (AFM) images of the bilayers showed that the headgroups might be bent, forming small divots in the surface. These divots may help expose the PHSRN synergy-binding domain. Parallel studies undertaken by fellow group members showed that human

  1. A Novel Bio-mimetic Wireless Micro Robot for Endoscope

    Institute of Scientific and Technical Information of China (English)

    YE Dong-dong; YAN Guo-zheng; WANG Kua-dong; MA Guan-ying

    2008-01-01

    A novel bio-mimetic wireless micro robot for endoscope is developed. Its autonomous manner is earthworm-like and driven by linear actuators based on DC motor. It is different from the conventional micro robot endoscope that wireless module is used for communicating and power transfer. The fabricated micro robot system is detailedly described, including structure, micro robot locomotion principle, communication control module and wireless power transfer module. The experimental results show that the driving force of the lineaar actuator can reach to 2.55 N and supplying power is up to 480 mW DC power for receiving coil in the proposed system, which all fulfill the need of the micro robot system. The micro robot can creep reliably in the large intestine of pig and other contact environments.

  2. Possible Role of Brain-Derived Neurotrophic Factor (BDNF) in Autism Spectrum Disorder: Current Status

    International Nuclear Information System (INIS)

    Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family of survival-promoting molecules, plays a vital role in the growth, development, maintenance, and function of several neuronal systems. The purpose of this review is to document the support for the involvement of this molecule in the maintenance of normal cognitive, emotional functioning, and to outline recent developments in the content of Autism spectrum disorder (ASD). Current and future treatment development can be guided by developing understanding of this molecules actions in the brain and the ways the expression of BDNF can be planned. Over the years, research findings suggested a critical role played by BDNF in the development of autism including increased serum concentrations of BDNF in children with autism and identification of different forms of BDNF in families of autistic individuals. (author)

  3. Striatal dopamine transporter binding correlates with serum BDNF levels in patients with striatal dopaminergic neurodegeneration

    DEFF Research Database (Denmark)

    Ziebell, Morten; Khalid, Usman; Klein, Anders B;

    2012-01-01

    Compelling evidence has shown, that neurotrophins responsible for the regulation of neuronal growth, survival, and differentiation are involved in neurodegenerative diseases. Whereas lower serum levels of brain derived neurotrophic factor (BDNF) have been observed in patients with Parkinson......'s disease, no studies have directly related the degree of striatal neurodegeneration of dopaminergic neurons (DA) with serum BDNF levels. In this study we examined the relationship between striatal neurodegeneration as determined with (123)I-PE2I-single photon emission computer tomography (SPECT) and serum...... BDNF levels in patients with parkinsonism. Twenty-one patients with abnormal in vivo striatal dopamine transporter (DAT) binding as evidenced with [(123)I]PE2I SPECT brain scanning were included. Samples for serum BDNF levels were collected at the time of the SPECT scanning, and BDNF was measured...

  4. A non-linear constrained optimization technique for the mimetic finite difference method

    Energy Technology Data Exchange (ETDEWEB)

    Manzini, Gianmarco [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Svyatskiy, Daniil [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bertolazzi, Enrico [Univ. of Trento (Italy); Frego, Marco [Univ. of Trento (Italy)

    2014-09-30

    This is a strategy for the construction of monotone schemes in the framework of the mimetic finite difference method for the approximation of diffusion problems on unstructured polygonal and polyhedral meshes.

  5. Brain BDNF levels are dependent on cerebrovascular endothelium-derived nitric oxide.

    Science.gov (United States)

    Banoujaafar, Hayat; Monnier, Alice; Pernet, Nicolas; Quirié, Aurore; Garnier, Philippe; Prigent-Tessier, Anne; Marie, Christine

    2016-09-01

    Scientific evidence continues to demonstrate a link between endothelial function and cognition. Besides, several studies have identified a complex interplay between nitric oxide (NO) and brain-derived neurotrophic factor (BDNF), a neurotrophin largely involved in cognition. Therefore, this study investigated the link between cerebral endothelium-derived NO and BDNF signaling. For this purpose, levels of BDNF and the phosphorylated form of endothelial NO synthase at serine 1177 (p-eNOS) were simultaneously measured in the cortex and hippocampus of rats subjected to either bilateral common carotid occlusion (n = 6), physical exercise (n = 6) or a combination of both (n = 6) as experimental approaches to modulate flow-induced NO production by the cerebrovasculature. Tropomyosin-related kinase type B (TrkB) receptors and its phosphorylated form at tyrosine 816 (p-TrkB) were also measured. Moreover, we investigated BDNF synthesis in brain slices exposed to the NO donor glyceryl trinitrate. Our results showed increased p-eNOS and BDNF levels after exercise and decreased levels after vascular occlusion as compared to corresponding controls, with a positive correlation between changes in p-eNOS and BDNF (r = 0.679). Exercise after vascular occlusion did not change levels of these proteins. Gyceryl trinitrate increased proBDNF and BDNF levels in brain slices, thus suggesting a possible causal relationship between NO and BDNF. Moreover, vascular occlusion, like exercise, resulted in increased TrkB and p-TrkB levels, whereas no change was observed with the combination of both. These results suggest that brain BDNF signaling may be dependent on cerebral endothelium-derived NO production. PMID:27306299

  6. Silencing Status Epilepticus-Induced BDNF Expression with Herpes Simplex Virus Type-1 Based Amplicon Vectors.

    Directory of Open Access Journals (Sweden)

    Chiara Falcicchia

    Full Text Available Brain-derived neurotrophic factor (BDNF has been found to produce pro- but also anti-epileptic effects. Thus, its validity as a therapeutic target must be verified using advanced tools designed to block or to enhance its signal. The aim of this study was to develop tools to silence the BDNF signal. We generated Herpes simplex virus type 1 (HSV-1 derived amplicon vectors, i.e. viral particles containing a genome of 152 kb constituted of concatameric repetitions of an expression cassette, enabling the expression of the gene of interest in multiple copies. HSV-1 based amplicon vectors are non-pathogenic and have been successfully employed in the past for gene delivery into the brain of living animals. Therefore, amplicon vectors should represent a logical choice for expressing a silencing cassette, which, in multiple copies, is expected to lead to an efficient knock-down of the target gene expression. Here, we employed two amplicon-based BDNF silencing strategies. The first, antisense, has been chosen to target and degrade the cytoplasmic mRNA pool of BDNF, whereas the second, based on the convergent transcription technology, has been chosen to repress transcription at the BDNF gene. Both these amplicon vectors proved to be effective in down-regulating BDNF expression in vitro, in BDNF-expressing mesoangioblast cells. However, only the antisense strategy was effective in vivo, after inoculation in the hippocampus in a model of status epilepticus in which BDNF mRNA levels are strongly increased. Interestingly, the knocking down of BDNF levels induced with BDNF-antisense was sufficient to produce significant behavioral effects, in spite of the fact that it was produced only in a part of a single hippocampus. In conclusion, this study demonstrates a reliable effect of amplicon vectors in knocking down gene expression in vitro and in vivo. Therefore, this approach may find broad applications in neurobiological studies.

  7. Silencing Status Epilepticus-Induced BDNF Expression with Herpes Simplex Virus Type-1 Based Amplicon Vectors.

    Science.gov (United States)

    Falcicchia, Chiara; Trempat, Pascal; Binaschi, Anna; Perrier-Biollay, Coline; Roncon, Paolo; Soukupova, Marie; Berthommé, Hervé; Simonato, Michele

    2016-01-01

    Brain-derived neurotrophic factor (BDNF) has been found to produce pro- but also anti-epileptic effects. Thus, its validity as a therapeutic target must be verified using advanced tools designed to block or to enhance its signal. The aim of this study was to develop tools to silence the BDNF signal. We generated Herpes simplex virus type 1 (HSV-1) derived amplicon vectors, i.e. viral particles containing a genome of 152 kb constituted of concatameric repetitions of an expression cassette, enabling the expression of the gene of interest in multiple copies. HSV-1 based amplicon vectors are non-pathogenic and have been successfully employed in the past for gene delivery into the brain of living animals. Therefore, amplicon vectors should represent a logical choice for expressing a silencing cassette, which, in multiple copies, is expected to lead to an efficient knock-down of the target gene expression. Here, we employed two amplicon-based BDNF silencing strategies. The first, antisense, has been chosen to target and degrade the cytoplasmic mRNA pool of BDNF, whereas the second, based on the convergent transcription technology, has been chosen to repress transcription at the BDNF gene. Both these amplicon vectors proved to be effective in down-regulating BDNF expression in vitro, in BDNF-expressing mesoangioblast cells. However, only the antisense strategy was effective in vivo, after inoculation in the hippocampus in a model of status epilepticus in which BDNF mRNA levels are strongly increased. Interestingly, the knocking down of BDNF levels induced with BDNF-antisense was sufficient to produce significant behavioral effects, in spite of the fact that it was produced only in a part of a single hippocampus. In conclusion, this study demonstrates a reliable effect of amplicon vectors in knocking down gene expression in vitro and in vivo. Therefore, this approach may find broad applications in neurobiological studies.

  8. The relationship between serum brain-derived neurotrophic factor (BDNF) and cardiometabolic indices in schizophrenia.

    Science.gov (United States)

    Nurjono, Milawaty; Tay, Yi Hang; Lee, Jimmy

    2014-08-01

    Brain derived neurotrophic factor (BDNF), which has been implicated in the pathogenesis of schizophrenia, has been recently shown to be involved in the regulation of metabolism and energy homeostasis. This study seeks to examine the relationship between BDNF, metabolic indices and cardiovascular (CVD) risk in patients with schizophrenia. Medical histories, demographic information and anthropometric measurements were collected and analyzed from 61 participants with schizophrenia. Fasting glucose and lipids were measured in a central laboratory, and serum BDNF was analyzed using commercially available enzyme-linked immunosorbent assay (ELISA). The 10-year CVD risk for each participant was computed using the Framingham risk score (FRS). Linear regressions were performed to examine the relationships between serum BDNF with body mass index (BMI), blood pressure (BP), triglycerides (TG), total cholesterol, high-density lipoprotein cholesterol (HDL-C) and glucose. To examine the relationship between serum BDNF and FRS, serum BDNF was categorized into quartiles, and a multiple regression was performed. After adjusting for age, gender and current smoking status, diastolic BP (dBP) (p=0.045) and TG (p=0.015) were found to be significantly associated with serum BDNF. Participants in the highest quartile of serum BDNF had a 3.3 times increase in FRS over those in the lowest quartile. Our findings support the possible regulatory role of BDNF in metabolism and cardiovascular homeostasis among patients with schizophrenia similar to that observed among the non-mentally ill. Serum BDNF not only present itself as a candidate biomarker of schizophrenia but also might be a viable marker of metabolic co-morbidities associated with schizophrenia.

  9. Nonconventional amide bond formation catalysis: programming enzyme specificity with substrate mimetics

    OpenAIRE

    F. Bordusa

    2000-01-01

    This article reports on the design and characteristics of substrate mimetics in protease-catalyzed reactions. Firstly, the basis of protease-catalyzed peptide synthesis and the general advantages of substrate mimetics over common acyl donor components are described. The binding behavior of these artificial substrates and the mechanism of catalysis are further discussed on the basis of hydrolysis, acyl transfer, protein-ligand docking, and molecular dynamics studies on the trypsin model. The g...

  10. Superoxide radical induces sclerotial differentiation in filamentous phytopathogenic fungi: a superoxide dismutase mimetics study.

    Science.gov (United States)

    Papapostolou, Ioannis; Georgiou, Christos D

    2010-03-01

    This study shows that the superoxide radical (O(2) *( -)), a direct indicator of oxidative stress, is involved in the differentiation of the phytopathogenic filamentous fungi Rhizoctonia solani, Sclerotinia sclerotiorum, Sclerotium rolfsii and Sclerotinia minor, shown by using superoxide dismutase (SOD) mimetics to decrease their sclerotial differentiation. The production rate of O(2) *(-) and SOD levels in these fungi, as expected, were significantly lowered by the SOD mimetics, with concomitant decrease of the indirect indicator of oxidative stress, lipid peroxidation. PMID:20007647

  11. Reissner-Nordstr\\"om Black Holes in Mimetic $F(R)$ Gravity

    CERN Document Server

    Oikonomou, V K

    2015-01-01

    In this paper we study under which conditions the Reissner-Nordstr\\"om-anti de Sitter black hole can be a solution of the vacuum mimetic $F(R)$ gravity with Lagrange multiplier and mimetic scalar potential. As we demonstrate, the resulting picture in the mimetic $F(R)$ gravity case, is different in comparison to the ordinary $F(R)$ gravity case, with the two descriptions resulting to a different set of constraints that need to hold true. We also investigate the metric perturbations in the mimetic $F(R)$ gravity case, for the Reissner-Nordstr\\"om-anti de Sitter black hole metric, at first order of the perturbed variables. Interestingly enough, the resulting equations are identical to the ones corresponding to the ordinary $F(R)$ gravity Reissner-Nordstr\\"om-anti de Sitter black hole, at least at first order. We attribute this feature to the particular form of the Reissner-Nordstr\\"om-anti de Sitter metric, and we speculate for which cases there could be differences between the mimetic and non-mimetic case. Sin...

  12. Mixed mimetic spectral element method for Stokes flow: A pointwise divergence-free solution

    Science.gov (United States)

    Kreeft, Jasper; Gerritsma, Marc

    2013-05-01

    In this paper we apply the recently developed mimetic discretization method to the mixed formulation of the Stokes problem in terms of vorticity, velocity and pressure. The mimetic discretization presented in this paper and in Kreeft et al. [51] is a higher-order method for curvilinear quadrilaterals and hexahedrals. Fundamental is the underlying structure of oriented geometric objects, the relation between these objects through the boundary operator and how this defines the exterior derivative, representing the grad, curl and div, through the generalized Stokes theorem. The mimetic method presented here uses the language of differential k-forms with k-cochains as their discrete counterpart, and the relations between them in terms of the mimetic operators: reduction, reconstruction and projection. The reconstruction consists of the recently developed mimetic spectral interpolation functions. The most important result of the mimetic framework is the commutation between differentiation at the continuous level with that on the finite dimensional and discrete level. As a result operators like gradient, curl and divergence are discretized exactly. For Stokes flow, this implies a pointwise divergence-free solution. This is confirmed using a set of test cases on both Cartesian and curvilinear meshes. It will be shown that the method converges optimally for all admissible boundary conditions.

  13. SMAC mimetic Debio 1143 synergizes with taxanes, topoisomerase inhibitors and bromodomain inhibitors to impede growth of lung adenocarcinoma cells.

    Science.gov (United States)

    Langdon, Casey G; Wiedemann, Norbert; Held, Matthew A; Mamillapalli, Ramanaiah; Iyidogan, Pinar; Theodosakis, Nicholas; Platt, James T; Levy, Frederic; Vuagniaux, Gregoire; Wang, Shaomeng; Bosenberg, Marcus W; Stern, David F

    2015-11-10

    Targeting anti-apoptotic proteins can sensitize tumor cells to conventional chemotherapies or other targeted agents. Antagonizing the Inhibitor of Apoptosis Proteins (IAPs) with mimetics of the pro-apoptotic protein SMAC is one such approach. We used sensitization compound screening to uncover possible agents with the potential to further sensitize lung adenocarcinoma cells to the SMAC mimetic Debio 1143. Several compounds in combination with Debio 1143, including taxanes, topoisomerase inhibitors, and bromodomain inhibitors, super-additively inhibited growth and clonogenicity of lung adenocarcinoma cells. Co-treatment with Debio 1143 and the bromodomain inhibitor JQ1 suppresses the expression of c-IAP1, c-IAP2, and XIAP. Non-canonical NF-κB signaling is also activated following Debio 1143 treatment, and Debio 1143 induces the formation of the ripoptosome in Debio 1143-sensitive cell lines. Sensitivity to Debio 1143 and JQ1 co-treatment was associated with baseline caspase-8 expression. In vivo treatment of lung adenocarcinoma xenografts with Debio 1143 in combination with JQ1 or docetaxel reduced tumor volume more than either single agent alone. As Debio 1143-containing combinations effectively inhibited both in vitro and in vivo growth of lung adenocarcinoma cells, these data provide a rationale for Debio 1143 combinations currently being evaluated in ongoing clinical trials and suggest potential utility of other combinations identified here.

  14. Comparison of CR36, a new heparan mimetic, and pentosan polysulfate in the treatment of prion diseases.

    Science.gov (United States)

    Larramendy-Gozalo, Claire; Barret, Agnès; Daudigeos, Estelle; Mathieu, Emilie; Antonangeli, Lucie; Riffet, Cécile; Petit, Emmanuel; Papy-Garcia, Dulce; Barritault, Denis; Brown, Paul; Deslys, Jean-Philippe

    2007-03-01

    Sulfated polyanions, including pentosan polysulfate (PPS) and heparan mimetics, number among the most effective drugs that have been used in experimental models of prion disease and are presumed to act in competition with endogenous heparan sulfate proteoglycans as co-receptors for prion protein (PrP) on the cell surface. PPS has been shown to prolong the survival of animals after intracerebral perfusion and is in limited use for the experimental treatment of human transmissible spongiform encephalopathies (TSEs). Here, PPS is compared with CR36, a new heparan mimetic. Ex vivo, CR36 was more efficient than PPS in reducing PrPres in scrapie-infected cell cultures and showed long-lasting activity. In vivo, CR36 showed none of the acute toxicity observed with PPS and reduced PrPres accumulation in spleens, but had only a marginal effect on the survival time of mice infected with bovine spongiform encephalopathy. In contrast, mice treated with PPS that survived the initial toxic mortality had no detectable PrPres in the spleens and lived 185 days longer than controls (+55%). These results show, once again, that anti-TSE drugs cannot be encouraged for human therapeutic trials solely on the basis of in vitro or ex vivo observations, but must first be subjected to in vivo animal studies.

  15. Apolipoprotein E-mimetics inhibit neurodegeneration and restore cognitive functions in a transgenic Drosophila model of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Svetlana Sarantseva

    Full Text Available BACKGROUND: Mutations of the amyloid precursor protein gene (APP are found in familial forms of Alzheimer's disease (AD and some lead to the elevated production of amyloid-beta-protein (Abeta. While Abeta has been implicated in the causation of AD, the exact role played by Abeta and its APP precursor are still unclear. PRINCIPAL FINDINGS: In our study, Drosophila melanogaster transgenics were established as a model to analyze AD-like pathology caused by APP overexpression. We demonstrated that age related changes in the levels and pattern of synaptic proteins accompanied progressive neurodegeneration and impairment of cognitive functions in APP transgenic flies, but that these changes may be independent from the generation of Abeta. Using novel peptide mimetics of Apolipoprotein-E, COG112 or COG133 proved to be neuroprotective and significantly improved the learning and memory of APP transgenic flies. CONCLUSIONS: The development of neurodegeneration and cognitive deficits was corrected by injections of COG112 or COG133, novel mimetics of apolipoprotein-E (apoE with neuroprotective activities.

  16. A novel BH3 mimetic efficiently induces apoptosis in melanoma cells through direct binding to anti-apoptotic Bcl-2 family proteins, including phosphorylated Mcl-1.

    Science.gov (United States)

    Liu, Yubo; Xie, Mingzhou; Song, Ting; Sheng, Hongkun; Yu, Xiaoyan; Zhang, Zhichao

    2015-03-01

    The Bcl-2 family modulates sensitivity to chemotherapy in many cancers, including melanoma, in which the RAS/BRAF/MEK/ERK pathway is constitutively activated. Mcl-1, a major anti-apoptotic protein in the Bcl-2 family, is extensively expressed in melanoma and contributes to melanoma's well-documented chemoresistance. Here, we provide the first evidence that Mcl-1 phosphorylation at T163 by ERK1/2 and JNK is associated with the resistance of melanoma cell lines to the existing BH3 mimetics gossypol, S1 and ABT-737, and a novel anti-apoptotic mechanism of phosphorylated Mcl-1 (pMcl-1) is revealed. pMcl-1 antagonized the known BH3 mimetics by sequestering pro-apoptotic proteins that were released from Bcl-2/Mcl-1. Furthermore, an anthraquinone BH3 mimetic, compound 6, was identified to be the first small molecule to that induces endogenous apoptosis in melanoma cells by directly binding Bcl-2, Mcl-1, and pMcl-1 and disrupting the heterodimers of these proteins. Although compound 6 induced upregulation of the pro-apoptotic protein Noxa, its apoptotic induction was independent of Noxa. These data reveal the promising therapeutic potential of targeting pMcl-1 to treat melanoma. Compound 6 is therefore a potent drug that targets pMcl-1 in melanoma.

  17. EPOR-Based Purification and Analysis of Erythropoietin Mimetic Peptides from Human Urine by Cys-Specific Cleavage and LC/MS/MS

    Science.gov (United States)

    Vogel, Matthias; Thomas, Andreas; Schänzer, Wilhelm; Thevis, Mario

    2015-09-01

    The development of a new class of erythropoietin mimetic agents (EMA) for treating anemic conditions has been initiated with the discovery of oligopeptides capable of dimerizing the erythropoietin (EPO) receptor and thus stimulating erythropoiesis. The most promising amino acid sequences have been mounted on various different polymeric structures or carrier molecules to obtain highly active EPO-like drugs exhibiting beneficial and desirable pharmacokinetic profiles. Concomitant with creating new therapeutic options, erythropoietin mimetic peptide (EMP)-based drug candidates represent means to artificially enhance endurance performance and necessitate coverage by sports drug testing methods. Therefore, the aim of the present study was to develop a strategy for the comprehensive detection of EMPs in doping controls, which can be used complementary to existing protocols. Three model EMPs were used to provide proof-of-concept data. Following EPO receptor-facilitated purification of target analytes from human urine, the common presence of the cysteine-flanked core structure of EMPs was exploited to generate diagnostic peptides with the aid of a nonenzymatic cleavage procedure. Sensitive detection was accomplished by targeted-SIM/data-dependent MS2 analysis. Method characterization was conducted for the EMP-based drug peginesatide concerning specificity, linearity, precision, recovery, stability, ion suppression/enhancement, and limit of detection (LOD, 0.25 ng/mL). Additionally, first data for the identification of the erythropoietin mimetic peptides EMP1 and BB68 were generated, demonstrating the multi-analyte testing capability of the presented approach.

  18. Study of the profile of the neurotrophin BDNF in new leprosy cases before, during and after multidrug therapy

    Directory of Open Access Journals (Sweden)

    Rosane Dias Costa

    2011-02-01

    Full Text Available Brain-derived neurotrophic factor (BDNF is a neurotrophin involved in the survival of neurons and growth and differentiation of dendrites and axons. The purpose of the present study was to evaluate plasma levels of BDNF of leprosy patients at different stages of multidrug therapy (MDT in comparison with non-infected individuals. Plasma levels of BDNF were measured by ELISA in 30 healthy controls and 37 leprosy patients at diagnosis, during and after MDT. Plasma levels of BDNF tended to be higher in control subjects in comparison with leprosy patients, but this difference does not reach statistical significance. Interestingly, BDNF levels changed following MDT, achieving statistical difference only at the 2nd dose of MDT. These results indicate that BDNF may not be a surrogate marker of leprosy infection and/or related neuropathy. Further research is needed to investigate the meaning of BDNF level changes following leprosy treatment.

  19. BDNF polymorphism associates with decline in set shifting in Parkinson's disease.

    Science.gov (United States)

    van der Kolk, Nicolien M; Speelman, Arlene D; van Nimwegen, Marlies; Kessels, Roy P C; IntHout, Joanna; Hakobjan, Marina; Munneke, Marten; Bloem, Bastiaan R; van de Warrenburg, Bart P

    2015-03-01

    Parkinson's disease (PD) is a neurodegenerative disorder caused by nigrostriatal dopaminergic degeneration. Brain-derived neurotrophic factor (BDNF) is a key protein in brain plasticity and is particularly important for survival of dopaminergic neurons. The Val66Met polymorphism of BDNF (rs6265) has been associated with functional differences (mainly cognitive) between healthy adults and also with differences in the clinical expression of several other neuropsychiatric illnesses including PD. However, these studies used different outcome measures, have not been replicated, and were cross sectional, making it difficult to establish the role of BDNF in the clinical variability of PD. Here, a large cohort of 384 PD patients were followed up for 2 years, and associations between BDNF genotype and various clinical characteristics were examined. The BDNF Met-allele carriers showed a significantly smaller decline in set shifting during follow-up compared with the homozygous BDNF Val-allele carriers. Contrary to previous assumptions, these results indicate that mental flexibility is one of the cognitive processes that may benefit from the BDNF Met allele in PD patients. PMID:25444596

  20. BDNF promotes target innervation of Xenopus mandibular trigeminal axons in vivo

    Directory of Open Access Journals (Sweden)

    Ishibashi Shoko

    2007-05-01

    Full Text Available Abstract Background Trigeminal nerves consist of ophthalmic, maxillary, and mandibular branches that project to distinct regions of the facial epidermis. In Xenopus embryos, the mandibular branch of the trigeminal nerve extends toward and innervates the cement gland in the anterior facial epithelium. The cement gland has previously been proposed to provide a short-range chemoattractive signal to promote target innervation by mandibular trigeminal axons. Brain derived neurotrophic factor, BDNF is known to stimulate axon outgrowth and branching. The goal of this study is to determine whether BDNF functions as the proposed target recognition signal in the Xenopus cement gland. Results We found that the cement gland is enriched in BDNF mRNA transcripts compared to the other neurotrophins NT3 and NT4 during mandibular trigeminal nerve innervation. BDNF knockdown in Xenopus embryos or specifically in cement glands resulted in the failure of mandibular trigeminal axons to arborise or grow into the cement gland. BDNF expressed ectodermal grafts, when positioned in place of the cement gland, promoted local trigeminal axon arborisation in vivo. Conclusion BDNF is necessary locally to promote end stage target innervation of trigeminal axons in vivo, suggesting that BDNF functions as a short-range signal that stimulates mandibular trigeminal axon arborisation and growth into the cement gland.

  1. Serum brain-derived neurotrophic factor (BDNF) levels in attention deficit-hyperactivity disorder (ADHD).

    Science.gov (United States)

    Scassellati, Catia; Zanardini, Roberta; Tiberti, Alessandra; Pezzani, Marco; Valenti, Vera; Effedri, Paola; Filippini, Elena; Conte, Stefano; Ottolini, Alberto; Gennarelli, Massimo; Bocchio-Chiavetto, Luisella

    2014-03-01

    It has been proposed that the neurotrophin brain-derived neurotrophic factor (BDNF) may be involved in attention deficit-hyperactivity disorder (ADHD) etiopathogenesis. Alterations in BDNF serum levels have been observed in childhood/adulthood neurodevelopmental pathologies, but no evidence is available for BDNF serum concentrations in ADHD. The study includes 45 drug-naïve ADHD children and 45 age-sex matched healthy subjects. Concentration of serum BDNF was determined by the ELISA method. BDNF serum levels in patients with ADHD were not different from those of controls (mean ± SD; ADHD: 39.33 ± 10.41 ng/ml; controls: 38.82 ± 8.29 ng/ml, t = -0.26, p = 0.80). Our findings indicate no alteration of serum BDNF levels in untreated patients with ADHD. A further stratification for cognitive, neuropsychological and psychopathological assessment in a larger sample could be useful to clarify the role of BDNF in the endophenotype characterization of ADHD.

  2. Exercise does not protect against MPTP-induced neurotoxicity in BDNF haploinsufficient mice.

    Directory of Open Access Journals (Sweden)

    Kim M Gerecke

    Full Text Available Exercise has been demonstrated to potently protect substantia nigra pars compacta (SN dopaminergic neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP-induced neurotoxicity. One mechanism proposed to account for this neuroprotection is the upregulation of neurotrophic factors. Several neurotrophic factors, including Brain Derived Neurotrophic Factor (BDNF, have been shown to upregulate in response to exercise. In order to determine if exercise-induced neuroprotection is dependent upon BDNF, we compared the neuroprotective effects of voluntary exercise in mice heterozygous for the BDNF gene (BDNF+/- with strain-matched wild-type (WT mice. Stereological estimates of SNpc DA neurons from WT mice allowed 90 days exercise via unrestricted running demonstrated complete protection against the MPTP-induced neurotoxicity. However, BDNF+/- mice allowed 90 days of unrestricted exercise were not protected from MPTP-induced SNpc DA neuron loss. Proteomic analysis comparing SN and striatum from 90 day exercised WT and BDNF+/- mice showed differential expression of proteins related to energy regulation, intracellular signaling and trafficking. These results suggest that a full genetic complement of BDNF is critical for the exercise-induced neuroprotection of SNpc DA neurons.

  3. Plasma brain derived neurotrophic factor (BDNF) and response to ketamine in treatment-resistant depression.

    Science.gov (United States)

    Haile, C N; Murrough, J W; Iosifescu, D V; Chang, L C; Al Jurdi, R K; Foulkes, A; Iqbal, S; Mahoney, J J; De La Garza, R; Charney, D S; Newton, T F; Mathew, S J

    2014-02-01

    Ketamine produces rapid antidepressant effects in treatment-resistant depression (TRD), but the magnitude of response varies considerably between individual patients. Brain-derived neurotrophic factor (BDNF) has been investigated as a biomarker of treatment response in depression and has been implicated in the mechanism of action of ketamine. We evaluated plasma BDNF and associations with symptoms in 22 patients with TRD enrolled in a randomized controlled trial of ketamine compared to an anaesthetic control (midazolam). Ketamine significantly increased plasma BDNF levels in responders compared to non-responders 240 min post-infusion, and Montgomery-Åsberg Depression Rating Scale (MADRS) scores were negatively correlated with BDNF (r=-0.701, p = 0.008). Plasma BDNF levels at 240 min post-infusion were highly negatively associated with MADRS scores at 240 min (r = -0.897, p=.002), 24 h (r = -0.791, p = 0.038), 48 h (r = -0.944, p = 0.001) and 72 h (r = -0.977, p = 0.010). No associations with BDNF were found for patients receiving midazolam. These data support plasma BDNF as a peripheral biomarker relevant to ketamine antidepressant response.

  4. Repair of spinal cord injury by neural stem cells modified with BDNF gene in rats

    Institute of Scientific and Technical Information of China (English)

    Wei LI; Wen-Qin CAI; Cheng-Ren LI

    2006-01-01

    Objective To explore repair of spinal cord injury by neural stem cells (NSCs) modified with brain derived neurotrophic factor (BDNF) gene (BDNF-NSCs) in rats. Methods Neural stem cells modified with BDNF gene were transplanted into the complete transection site of spinal cord at the lumbar 4 (L4) level in rats. Motor function of rats'hind limbs was observed and HE and X-gal immunocytochemical staining, in situ hybridization, and retrograde HRP tracing were also performed. Results BDNF-NSCs survived and integrated well with host spinal cord. In the transplant group, some X-gal positive, NF-200 positive, GFAP positive, BDNF positive, and BDNF mRNA positive cells, and many NF-200 positive nerve fibers were observed in the injury site. Retrograde HRP tracing through sciatic nerve showed some HRP positive cells and nerve fibers near the rostral side of the injury one month after transplant and with time, they increased in number. Examinations on rats' motor function and behavior demonstrated that motor function of rats' hind limbs improved better in the transplant group than the injury group. Conclusion BDNF-NSCs can survive, differentiate,and partially integrate with host spinal cord, and they significantly ameliorate rats ' motor function of hind limbs, indicating their promising role in repairing spinal cord injury.

  5. Reissner–Nordström Anti-de Sitter Black Holes in Mimetic F(R Gravity

    Directory of Open Access Journals (Sweden)

    V. K. Oikonomou

    2016-05-01

    Full Text Available In this paper, we study under which conditions the Reissner–Nordström anti-de Sitter black hole can be a solution of the vacuum mimetic F ( R gravity with Lagrange multiplier and mimetic scalar potential. As the author demonstrates, the resulting picture in the mimetic F ( R gravity case is a trivial extension of the standard F ( R approach, and in effect, the metric perturbations in the mimetic F ( R gravity case, for the Reissner–Nordström anti-de Sitter black hole metric, at the first order of the perturbed variables are the same at the leading order.

  6. BDNF and its TrkB receptor in human fracture healing.

    Science.gov (United States)

    Kilian, Olaf; Hartmann, Sonja; Dongowski, Nicole; Karnati, Srikanth; Baumgart-Vogt, Eveline; Härtel, Frauke V; Noll, Thomas; Schnettler, Reinhard; Lips, Katrin Susanne

    2014-09-01

    Fracture healing is a physiological process of repair which proceeds in stages, each characterized by a different predominant tissue in the fracture gap. Matrix reorganization is regulated by cytokines and growth factors. Neurotrophins and their receptors might be of importance to osteoblasts and endothelial cells during fracture healing. The aim of this study was to examine the presence of brain-derived neurotrophic factor (BDNF) and its tropomyosin-related kinase B receptor (TrkB) during human fracture healing. BDNF and TrkB were investigated in samples from human fracture gaps and cultured cells using RT-PCR, Western blot, and immunohistochemistry. Endothelial cells and osteoblastic cell lines demonstrated a cytoplasmic staining pattern of BDNF and TrkB in vitro. At the mRNA level, BDNF and TrkB were expressed in the initial and osteoid formation phase of human fracture healing. In the granulation tissue of fracture gap, both proteins--BDNF and TrkB--are concentrated in endothelial and osteoblastic cells at the margins of woven bone suggesting their involvement in the formation of new vessels. There was no evidence of BDNF or TrkB during fracture healing in chondrocytes of human enchondral tissue. Furthermore, BDNF is absent in mature bone. Taken together, BDNF and TrkB are involved in vessel formation and osteogenic processes during human fracture healing. The detection of BDNF and its TrkB receptor during various stages of the bone formation process in human fracture gap tissue were shown for the first time. The current study reveals that both proteins are up-regulated in human osteoblasts and endothelial cells in fracture healing. PMID:24984919

  7. Cleavage of proBDNF to BDNF by a tolloid-like metalloproteinase is required for acquisition of in vitro eyeblink classical conditioning.

    Science.gov (United States)

    Keifer, Joyce; Sabirzhanov, Boris E; Zheng, Zhaoqing; Li, Wei; Clark, Timothy G

    2009-11-25

    The tolloid/bone morphogenetic protein-1 family of metalloproteinases have an important role in the regulation of embryonic pattern formation and tissue morphogenesis. Studies suggest that they participate in mechanisms of synaptic plasticity in adults, but very little is known about their function. Recently, we isolated a reptilian ortholog of the tolloid gene family designated turtle tolloid-like gene (tTll). Here, we examined the role of tTLL in an in vitro model of eyeblink classical conditioning using an isolated brainstem preparation to assess its role in synaptic plasticity during conditioning. Analysis by real-time reverse transcription-PCR shows that an extracellularly secreted form of tTLL, tTLLs, is transiently expressed in the early stages of conditioning during conditioned response acquisition, whereas a cytosolic form, tTLLc, is not. Short interfering RNA (siRNA)-directed gene knockdown and rescue of tTLL expression demonstrate that it is required for conditioning. Significantly, we show that tTLLs cleaves the precursor proBDNF into mature BDNF in cleavage assay studies, and application of recombinant tTLLs protein alone to preparations results in induction of mature BDNF expression. The mature form of BDNF is minimally expressed in preparations treated with anti-tTLL siRNA, and the synaptic incorporation of both GluR1- and GluR4-containing AMPA receptors is significantly reduced, resulting in suppression of conditioning. This is the first study to demonstrate that expression of an extracellularly secreted tolloid-like metalloproteinase is regulated in the early stages of classical conditioning and functions in the conversion of proBDNF to mature BDNF. The mature form of BDNF is required for synaptic delivery of AMPA receptors and acquisition of conditioned responses.

  8. 7,8-dihydroxyflavone, a small molecular TrkB agonist, is useful for treating various BDNF-implicated human disorders.

    Science.gov (United States)

    Liu, Chaoyang; Chan, Chi Bun; Ye, Keqiang

    2016-01-01

    Brain-derived neurotrophic factor (BDNF) regulates a variety of biological processes predominantly via binding to the transmembrane receptor tyrosine kinase TrkB. It is a potential therapeutic target in numerous neurological, mental and metabolic disorders. However, the lack of efficient means to deliver BDNF into the body imposes an insurmountable hurdle to its clinical application. To address this challenge, we initiated a cell-based drug screening to search for small molecules that act as the TrkB agonist. 7,8-Dihydroxyflavone (7,8-DHF) is our first reported small molecular TrkB agonist, which has now been extensively validated in various biochemical and cellular systems. Though binding to the extracellular domain of TrkB, 7,8-DHF triggers TrkB dimerization to induce the downstream signaling. Notably, 7,8-DHF is orally bioactive that can penetrate the brain blood barrier (BBB) to exert its neurotrophic activities in the central nervous system. Numerous reports suggest 7,8-DHF processes promising therapeutic efficacy in various animal disease models that are related to deficient BDNF signaling. In this review, we summarize our current knowledge on the binding activity and specificity, structure-activity relationship, pharmacokinetic and metabolism, and the pre-clinical efficacy of 7,8-DHF against some human diseases. PMID:26740873

  9. Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

    Energy Technology Data Exchange (ETDEWEB)

    Hennings, Leah; Artaud, Cecile; Jousheghany, Fariba; Monzavi-Karbassi, Behjatolah; Pashov, Anastas; Kieber-Emmons, Thomas, E-mail: tke@uams.edu [Winthrop P. Rockefeller Cancer Institute and Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, AR 72205 (United States)

    2011-11-11

    Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs). To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs) that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- and disaccharides are also expressed on normal tissue. To support the development of CMPs for clinical trial testing, we demonstrate in preclinical safety assessment studies in mice that vaccination with CMPs can enhance responses to TACAs without mediating tissue damage to normal cells expressing TACA. BALB/c mice were immunized with CMPs that mimic TACAs reactive with Griffonia simplicifolia lectin 1 (GS-I), and tissue reactivity of serum antibodies were compared with the tissue staining profile of GS-I. Tissues from CMP immunized mice were analyzed using hematoxylin and eosin stain, and Luxol-fast blue staining for myelination. Western blots of membranes from murine mammary 4T1 cells, syngeneic with BALB/c mice, were also compared using GS-I, immunized serum antibodies, and naive serum antibodies. CMP immunization enhanced glycan reactivities with no evidence of pathological autoimmunity in any immunized mice demonstrating that tissue damage is not an inevitable consequence of TACA reactive responses.

  10. Effects of combined BDNF and GDNF treatment on cultured dopaminergic midbrain neurons

    DEFF Research Database (Denmark)

    Sautter, J; Meyer, Morten; Spenger, C;

    1998-01-01

    -derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), or a combination of both. Dopamine content of the culture medium, the number of tyrosine hydroxylase-immunoreactive neurons, and culture volumes were moderately increased in the BDNF- and GDNF-treated cultures but significantly...... increased by 6.8-, 3.2- and 2.4-fold, respectively after treatment with the combination of both factors. We conclude that pretreatment of dopaminergic tissue in culture with a combination of BDNF and GDNF may be an effective means to improve the quality of tissue prior to grafting....

  11. Glycosaminoglycan-Mimetic Signals Direct the Osteo/Chondrogenic Differentiation of Mesenchymal Stem Cells in a Three-Dimensional Peptide Nanofiber Extracellular Matrix Mimetic Environment.

    Science.gov (United States)

    Arslan, Elif; Guler, Mustafa O; Tekinay, Ayse B

    2016-04-11

    Recent efforts in bioactive scaffold development focus strongly on the elucidation of complex cellular responses through the use of synthetic systems. Designing synthetic extracellular matrix (ECM) materials must be based on understanding of cellular behaviors upon interaction with natural and artificial scaffolds. Hence, due to their ability to mimic both the biochemical and mechanical properties of the native tissue environment, supramolecular assemblies of bioactive peptide nanostructures are especially promising for development of bioactive ECM-mimetic scaffolds. In this study, we used glycosaminoglycan (GAG) mimetic peptide nanofiber gel as a three-dimensional (3D) platform to investigate how cell lineage commitment is altered by external factors. We observed that amount of fetal bovine serum (FBS) presented in the cell media had synergistic effects on the ability of GAG-mimetic nanofiber gel to mediate the differentiation of mesenchymal stem cells into osteogenic and chondrogenic lineages. In particular, lower FBS concentration in the culture medium was observed to enhance osteogenic differentiation while higher amount FBS promotes chondrogenic differentiation in tandem with the effects of the GAG-mimetic 3D peptide nanofiber network, even in the absence of externally administered growth factors. We therefore demonstrate that mesenchymal stem cell differentiation can be specifically controlled by the combined influence of growth medium components and a 3D peptide nanofiber environment.

  12. Sex-specific association of brain-derived neurotrophic factor (BDNF) Val66Met polymorphism and plasma BDNF with attention-deficit/hyperactivity disorder in a drug-naïve Han Chinese sample.

    Science.gov (United States)

    Li, Haimei; Liu, Lu; Tang, Yilang; Ji, Ning; Yang, Li; Qian, Qiujin; Wang, Yufeng

    2014-07-30

    A functional polymorphism of the brain derived neurotrophic factor gene (BDNF) (Val66Met) has been suggested to be involved in the pathogenesis of attention-deficit/hyperactivity disorder (ADHD). It also has an impact on peripheral BDNF levels in psychiatric disorders. This study examined the association of Val66Met with plasma BDNF level of ADHD in Han Chinese children (170 medication - naïve ADHD patients and 155 unaffected controls, aged 6-16 years). The Val allele was showed a higher frequency in females with ADHD (n=84) than controls (P=0.029) from the case-control association study. The analysis of covariance (ANCOVA) indicated that the mean plasma BDNF levels of ADHD patients were significantly higher than that of controls (P=0.001). We performed both total sample and sex stratified analyses to investigate the effect of Val66Met genotype on the plasma BDNF levels, but only a trend of association was found in females with ADHD (n=84), with a tendency of lower plasma BDNF level in Val allele carriers than Met/Met genotype carriers (P=0.071). Our results suggested a sex-specific association between BDNF and ADHD. Furthermore, there was a possible sex-specific relationship between the BDNF Val66Met genotype and plasma BDNF levels. However, further studies are required to elucidate the role of BDNF in ADHD.

  13. The CNTF-derived peptide mimetic Cintrofin attenuates spatial-learning deficits in a rat post-status epilepticus model

    DEFF Research Database (Denmark)

    Russmann, Vera; Seeger, Natalie; Zellinger, Christina;

    2013-01-01

    Ciliary neurotrophic growth factor is considered a potential therapeutic agent for central nervous system diseases. We report first in vivo data of the ciliary neurotrophic growth factor peptide mimetic Cintrofin in a rat post-status epilepticus model. Cintrofin prevented long-term alterations...... in the number of doublecortin-positive neuronal progenitor cells and attenuated the persistence of basal dendrites. In contrast, Cintrofin did neither affect acute status epilepticus-associated alterations in hippocampal cell proliferation and neurogenesis nor reveal any relevant effect on seizure activity....... Whereas status epilepticus caused a significant disturbance in spatial learning in reversed peptide-treated rats, the performance of Cintrofin-treated rats did not differ from controls. The study confirms that Cintrofin comprises an active sequence mimicking effects of its parent molecule. While the data...

  14. Basal Lamina Mimetic Nanofibrous Peptide Networks for Skeletal Myogenesis

    Science.gov (United States)

    Yasa, I. Ceren; Gunduz, Nuray; Kilinc, Murat; Guler, Mustafa O.; Tekinay, Ayse B.

    2015-11-01

    Extracellular matrix (ECM) is crucial for the coordination and regulation of cell adhesion, recruitment, differentiation and death. Therefore, equilibrium between cell-cell and cell-matrix interactions and matrix-associated signals are important for the normal functioning of cells, as well as for regeneration. In this work, we describe importance of adhesive signals for myoblast cells’ growth and differentiation by generating a novel ECM mimetic peptide nanofiber scaffold system. We show that not only structure but also composition of bioactive signals are important for cell adhesion, growth and differentiation by mimicking the compositional and structural properties of native skeletal muscle basal lamina. We conjugated laminin-derived integrin binding peptide sequence, “IKVAV”, and fibronectin-derived well known adhesive sequence, “RGD”, into peptide nanostructures to provide adhesive and myogenic cues on a nanofibrous morphology. The myogenic and adhesive signals exhibited a synergistic effect on model myoblasts, C2C12 cells. Our results showed that self-assembled peptide nanofibers presenting laminin derived epitopes support adhesion, growth and proliferation of the cells and significantly promote the expression of skeletal muscle-specific marker genes. The functional peptide nanofibers used in this study present a biocompatible and biodegradable microenvironment, which is capable of supporting the growth and differentiation of C2C12 myoblasts into myotubes.

  15. Light-Adaptive Supramolecular Nacre-Mimetic Nanocomposites.

    Science.gov (United States)

    Zhu, Baolei; Noack, Manuel; Merindol, Remi; Barner-Kowollik, Christopher; Walther, Andreas

    2016-08-10

    Nature provides design paradigms for adaptive, self-healing, and synergistic high-performance structural materials. Nacre's brick-and-mortar architecture is renowned for combining stiffness, toughness, strength, and lightweightness. Although elaborate approaches exist to mimic its static structure and performance, and to incorporate functionalities for the engineering world, there is a profound gap in addressing adaptable mechanical properties, particularly using remote, quick, and spatiotemporal triggers. Here, we demonstrate a generic approach to control the mechanical properties of nacre-inspired nanocomposites by designing a photothermal energy cascade using colloidal graphene as light-harvesting unit and coupling it to molecularly designed, thermoreversible, supramolecular bonds in the nanoconfined soft phase of polymer/nanoclay nacre-mimetics. The light intensity leads to adaptive steady-states balancing energy uptake and dissipation. It programs the mechanical properties and switches the materials from high stiffness/strength to higher toughness within seconds under spatiotemporal control. We envisage possibilities beyond mechanical materials, for example, light-controlled (re)shaping or actuation in highly reinforced nanocomposites. PMID:27455047

  16. Serum inducible kinase is a positive regulator of cortical dendrite development and is required for BDNF-promoted dendritic arborization

    Institute of Scientific and Technical Information of China (English)

    Shun-Ling Guo; Guo-He Tan; Shuai Li; Xue-Wen Cheng; Ya Zhou; Yun-Fang Jia; Hui Xiong; Jiong Tao; Zhi-Qi Xiong

    2012-01-01

    Serum inducible kinase (SNK),also known as (p)olo-(l)ike (k)inase 2 (PLK2),is a known regulator of mitosis,synaptogenesis and synaptic homeostasis.However,its role in early cortical development is unknown.Herein,we show that snk is expressed in the cortical plate from embryonic day 14,but not in the ventricular/subventricular zones (VZ/SVZ),and SNK protein localizes to the soma and dendrites of cultured immature cortical neurons.Loss of SNK impaired dendritic but not axonal arborization in a dose-dependent manner and overexpression had opposite effects,both in vitro and in vivo.Overexpression of SNK also caused abnormal branching of the leading process of migrating cortical neurons in electroporated cortices.The kinase activity was necessary for these effects.Extracellular signalregulated kinase (ERK) pathway activity downstream of brain-derived neurotrophic factor (BDNF) stimulation led to increases in SNK protein expression via transcriptional regulation,and this upregulation was necessary for the growth-promoting effect of BDNF on dendritic arborization.Taken together,our results indicate that SNK is essential for dendrite morphogenesis in cortical neurons.

  17. Repeated electroconvulsive stimuli have long-lasting effects on hippocampal BDNF and decrease immobility time in the rat forced swim test.

    Science.gov (United States)

    Li, Bingjin; Suemaru, Katsuya; Cui, Ranji; Araki, Hiroaki

    2007-03-27

    Electroconvulsive therapy is considered an effective treatment for severe depression. However, the mechanisms for its long-lasting antidepressant efficacy are poorly understood. In the present study, we investigated changes of the immobility time in the forced swim test and brain-derived neurotrophic factor (BDNF) protein after withdrawal from 14-day repeated electroconvulsive stimuli (ECS, 50 mA, 0.2 s) in rats. Immobility time in the forced swim test was markedly decreased 6 h after withdrawal following 14-day ECS treatment. Thereafter, prolongation of the withdrawal period gradually diminished the decreasing effect of immobility time, but significant effects persisted for up to 3 days after the withdrawal. Locomotor activity in the open-field test increased 6 h after withdrawal from the ECS treatment, and the enhanced effect persisted for at least 7 days. The BDNF protein level in the hippocampus was markedly increased 6 h after the withdrawal, and remained high for at least 7 days. These findings provide further evidence that repeated ECS has long-lasting effect on increase in BDNF and locomotor activity and decrease in immobility time in the forced swim test.

  18. Two-Stage Translational Control of Dentate Gyrus LTP Consolidation Is Mediated by Sustained BDNF-TrkB Signaling to MNK

    Directory of Open Access Journals (Sweden)

    Debabrata Panja

    2014-11-01

    Full Text Available BDNF signaling contributes to protein-synthesis-dependent synaptic plasticity, but the dynamics of TrkB signaling and mechanisms of translation have not been defined. Here, we show that long-term potentiation (LTP consolidation in the dentate gyrus of live rodents requires sustained (hours BDNF-TrkB signaling. Surprisingly, this sustained activation maintains an otherwise labile signaling pathway from TrkB to MAP-kinase-interacting kinase (MNK. MNK activity promotes eIF4F translation initiation complex formation and protein synthesis in mechanistically distinct early and late stages. In early-stage translation, MNK triggers release of the CYFIP1/FMRP repressor complex from the 5′-mRNA cap. In late-stage translation, MNK regulates the canonical translational repressor 4E-BP2 in a synapse-compartment-specific manner. This late stage is coupled to MNK-dependent enhanced dendritic mRNA translation. We conclude that LTP consolidation in the dentate gyrus is mediated by sustained BDNF signaling to MNK and MNK-dependent regulation of translation in two functionally and mechanistically distinct stages.

  19. Brain-Derived Neurotrophic Factor (BDNF) Val66Met Polymorphism Differentially Predicts Hippocampal Function in Medication-Free Patients with Schizophrenia

    Science.gov (United States)

    Eisenberg, Daniel Paul; Ianni, Angela M.; Wei, Shau-Ming; Kohn, Philip D.; Kolachana, Bhaskar; Apud, José; Weinberger, Daniel R.; Berman, Karen F.

    2012-01-01

    A Val66Met single nucleotide polymorphism (SNP) in the brain-derived neurotrophic factor (BDNF) gene impairs activity-dependent BDNF release in cultured hippocampal neurons and predicts impaired memory and exaggerated basal hippocampal activity in healthy humans. Several clinical genetic association studies, along with multi-modal evidence for hippocampal dysfunction in schizophrenia indirectly suggest a relationship between schizophrenia and genetically-determined BDNF function in the hippocampus. To directly test this hypothesized relationship, we studied 47 medication-free patients with schizophrenia or schizoaffective disorder and 74 healthy comparison individuals with genotyping for the Val66Met SNP and [15O]H2O positron emission tomography (PET) to measure resting and working memory-related hippocampal regional cerebral blood flow (rCBF). In patients, harboring a Met allele was associated with significantly less hippocampal rCBF. This finding was opposite to the genotype effect seen in healthy participants, resulting in a significant diagnosis-by-genotype interaction. Exploratory analyses of interregional resting rCBF covariation revealed a specific and significant diagnosis-by-genotype interaction effect on hippocampal-prefrontal coupling. A diagnosis-by-genotype interaction was also found for working-memory related hippocampal rCBF change, which was uniquely attenuated in Met allele-carrying patients. Thus, both task-independent and task-dependent hippocampal neurophysiology accommodates a Met allelic background differently in patients with schizophrenia than in control subjects. Potentially consistent with the hypothesis that cellular sequelae of the BDNF Val66Met SNP interface with aspects of schizophrenic hippocampal and frontotemporal dysfunction, these results warrant future investigation to understand the contributions of unique patient trait or state variables to these robust interactions. PMID:23319002

  20. Administration of N-acetylserotonin and melatonin alleviate chronic ketamine-induced behavioural phenotype accompanying BDNF-independent and dependent converging cytoprotective mechanisms in the hippocampus.

    Science.gov (United States)

    Choudhury, Arnab; Singh, Seema; Palit, Gautam; Shukla, Shubha; Ganguly, Surajit

    2016-01-15

    Though growing evidence implicates both melatonin (MLT) and its immediate precursor N-acetylserotonin (NAS) in the regulation of hippocampal neurogenesis, their comparative mechanistic relationship with core behavioural correlates of psychiatric disorders is largely unknown. To address this issue, we investigated the ability of these indoleamines to mitigate the behavioral phenotypes associated with NMDA-receptor (NMDAR) hypofunction in mice. We demonstrated that exogenous MLT and NAS treatments attenuated the NMDAR antagonist (ketamine) induced immobility in the forced swim test (FST) but not the classical striatum-related hyperlocomotor activity phenotype. The MLT/NAS-mediated protection of the phenotype in FST could be correlated to the ability of these indoleamines to counteract the deleterious effects of chronic ketamine on pro-survival molecular events by restoring the activities in MEK-ERK and PI3K-AKT pathways in the hippocampus. MLT seems to modulate these pathways by promoting accumulation of the mature form of BDNF above the control (vehicle-treated) levels, perhaps via MLT receptor-dependent mechanisms and in the process overcoming the ketamine-induced down-regulation of BDNF. In contrast, NAS appears to partly restore the ketamine-induced decrease of BDNF to the control levels. In spite of this fundamental difference in modulating BDNF levels in the upstream events, both MLT and NAS seem to overlap in the TrkB-induced downstream pro-survival mechanisms in the hippocampus, providing protection against NMDAR-hypofunction related cellular events. Perhaps, this also signifies the physiological importance of robust MLT synthesizing machinery that converts serotonin to MLT, in ensuring positive impact on hippocampus-related symptoms in psychiatric disorders.

  1. Recombinant AAV-mediated Expression of Human BDNF Protects Neurons against Cell Apoptosis in Aβ-induced Neuronal Damage Model

    Institute of Scientific and Technical Information of China (English)

    LIU Zhaohui; MA Dongliang; FENG Gaifeng; MA Yanbing; HU Haitao

    2007-01-01

    The human brain-derived neurotrophic factor (hBDNF) gene was cloned by polymerase chain reaction and the recombinant adeno-associated viral vector inserted with hBDNF gene (AAV-hBDNF) was constructed. Cultured rat hippocampal neurons were treated with Aβ25-35 and serued as the experimental Aβ-induced neuronal damage model (AD model), and the AD model was infected with AAV-hBDNF to explore neuroprotective effects of expression of BDNF. Cell viability was assayed by MTT. The expression of bcl-2 anti-apoptosis protein was detected by immunocytochemical staining. The change of intracellular free Ca ion ([Ca2+]i) was measured by laser scanning confocal microscopy. The results showed that BDNF had protective effects against Aβ-induced neuronal damage. The expression of the bcl-2 anti-apoptosis protein was raised significantly and the balance of [Ca2+]i was maintained in the AAV-hBDNF treatment group as compared with AD model group. These data suggested that recombinant AAV mediated a stable expression of hBDNF in cultured hippocampal neurons and resulted in significant neuron protective effects in AD model. The BDNF may reduce neuron apoptosis through increasing the expression of the bcl-2 anti-apoptosis protein and inhibiting intracellular calcium overload. The viral vector-mediated gene expression of BDNF may pave the way of a novel therapeutic strategy for the treatment of neurodegenerative diseases such as Alzheimer's disease.

  2. The role of brain-derived neurotrophic factor (BDNF) in the development of neurogenic detrusor overactivity (NDO).

    Science.gov (United States)

    Frias, Bárbara; Santos, João; Morgado, Marlene; Sousa, Mónica Mendes; Gray, Susannah M Y; McCloskey, Karen D; Allen, Shelley; Cruz, Francisco; Cruz, Célia Duarte

    2015-02-01

    Neurogenic detrusor overactivity (NDO) is a well known consequence of spinal cord injury (SCI), recognizable after spinal shock, during which the bladder is areflexic. NDO emergence and maintenance depend on profound plastic changes of the spinal neuronal pathways regulating bladder function. It is well known that neurotrophins (NTs) are major regulators of such changes. NGF is the best-studied NT in the bladder and its role in NDO has already been established. Another very abundant neurotrophin is BDNF. Despite being shown that, acting at the spinal cord level, BDNF is a key mediator of bladder dysfunction and pain during cystitis, it is presently unclear if it is also important for NDO. This study aimed to clarify this issue. Results obtained pinpoint BDNF as an important regulator of NDO appearance and maintenance. Spinal BDNF expression increased in a time-dependent manner together with NDO emergence. In chronic SCI rats, BDNF sequestration improved bladder function, indicating that, at later stages, BDNF contributes NDO maintenance. During spinal shock, BDNF sequestration resulted in early development of bladder hyperactivity, accompanied by increased axonal growth of calcitonin gene-related peptide-labeled fibers in the dorsal horn. Chronic BDNF administration inhibited the emergence of NDO, together with reduction of axonal growth, suggesting that BDNF may have a crucial role in bladder function after SCI via inhibition of neuronal sprouting. These findings highlight the role of BDNF in NDO and may provide a significant contribution to create more efficient therapies to manage SCI patients. PMID:25653370

  3. The role of brain-derived neurotrophic factor (BDNF) in the development of neurogenic detrusor overactivity (NDO).

    Science.gov (United States)

    Frias, Bárbara; Santos, João; Morgado, Marlene; Sousa, Mónica Mendes; Gray, Susannah M Y; McCloskey, Karen D; Allen, Shelley; Cruz, Francisco; Cruz, Célia Duarte

    2015-02-01

    Neurogenic detrusor overactivity (NDO) is a well known consequence of spinal cord injury (SCI), recognizable after spinal shock, during which the bladder is areflexic. NDO emergence and maintenance depend on profound plastic changes of the spinal neuronal pathways regulating bladder function. It is well known that neurotrophins (NTs) are major regulators of such changes. NGF is the best-studied NT in the bladder and its role in NDO has already been established. Another very abundant neurotrophin is BDNF. Despite being shown that, acting at the spinal cord level, BDNF is a key mediator of bladder dysfunction and pain during cystitis, it is presently unclear if it is also important for NDO. This study aimed to clarify this issue. Results obtained pinpoint BDNF as an important regulator of NDO appearance and maintenance. Spinal BDNF expression increased in a time-dependent manner together with NDO emergence. In chronic SCI rats, BDNF sequestration improved bladder function, indicating that, at later stages, BDNF contributes NDO maintenance. During spinal shock, BDNF sequestration resulted in early development of bladder hyperactivity, accompanied by increased axonal growth of calcitonin gene-related peptide-labeled fibers in the dorsal horn. Chronic BDNF administration inhibited the emergence of NDO, together with reduction of axonal growth, suggesting that BDNF may have a crucial role in bladder function after SCI via inhibition of neuronal sprouting. These findings highlight the role of BDNF in NDO and may provide a significant contribution to create more efficient therapies to manage SCI patients.

  4. New mimetic peptides inhibitors of Αβ aggregation. Molecular guidance for rational drug design.

    Science.gov (United States)

    Barrera Guisasola, Exequiel E; Andujar, Sebastián A; Hubin, Ellen; Broersen, Kerensa; Kraan, Ivonne M; Méndez, Luciana; Delpiccolo, Carina M L; Masman, Marcelo F; Rodríguez, Ana M; Enriz, Ricardo D

    2015-05-01

    A new series of mimetic peptides possessing a significant Aβ aggregation modulating effect was reported here. These compounds were obtained based on a molecular modelling study which allowed us to perform a structural-based virtual selection. Monitoring Aβ aggregation by thioflavin T fluorescence and transmission electron microscopy revealed that fibril formation was significantly decreased upon prolonged incubation in presence of the active compounds. Dot blot analysis suggested a decrease of soluble oligomers strongly associated with cognitive decline in Alzheimer's disease. For the molecular dynamics simulations, we used an Aβ42 pentameric model where the compounds were docked using a blind docking technique. To analyze the dynamic behaviour of the complexes, extensive molecular dynamics simulations were carried out in explicit water. We also measured parameters or descriptors that allowed us to quantify the effect of these compounds as potential inhibitors of Aβ aggregation. Thus, significant alterations in the structure of our Aβ42 protofibril model were identified. Among others we observed the destruction of the regular helical twist, the loss of a stabilizing salt bridge and the loss of a stabilizing hydrophobic interaction in the β1 region. Our results may be helpful in the structural identification and understanding of the minimum structural requirements for these molecules and might provide a guide in the design of new aggregation modulating ligands.

  5. Smac mimetics and innate immune stimuli synergize to promote tumor death

    Science.gov (United States)

    Beug, Shawn T.; Tang, Vera A.; LaCasse, Eric C.; Cheung, Herman H.; Beauregard, Caroline E.; Brun, Jan; Nuyens, Jeffrey P.; Earl, Nathalie; St-Jean, Martine; Holbrook, Janelle; Dastidar, Himika; Mahoney, Douglas J.; Ilkow, Carolina; Le Boeuf, Fabrice; Bell, John C.; Korneluk, Robert G.

    2016-01-01

    Smac mimetic compounds (SMC), a class of drugs that sensitize cells to apoptosis by counteracting the activity of inhibitor of apoptosis (IAP) proteins, have proven safe in Phase I clinical trials in cancer patients. However, because SMCs act by enabling transduction of pro-apoptotic signals, SMC monotherapy may only be efficacious in the subset of patients whose tumors produce large quantities of death-inducing proteins such as inflammatory cytokines. As such, we reasoned that SMCs would synergize with agents that stimulate a potent yet safe “cytokine storm”. Here we show that oncolytic viruses and adjuvants such as poly(I:C) and CpG induce bystander death of cancer cells treated with SMCs that is mediated by interferon beta (IFNβ), tumor necrosis factor alpha (TNFα) and/or TNF-related apoptosis-inducing ligand (TRAIL). This combinatorial treatment resulted in tumor regression and extended survival in two mouse models of cancer. As these and other adjuvants have been proven safe in clinical trials, it may be worthwhile to explore their clinical efficacy in combination with SMCs. PMID:24463573

  6. BDNF is a novel marker of cognitive function in ageing women: the DR's EXTRA Study

    DEFF Research Database (Denmark)

    Komulainen, P.; Pedersen, Maria; Hanninen, T.;

    2008-01-01

    Brain-derived neurotrophic factor (BDNF) is one of the key molecules modulating brain plasticity. While low circulating levels of BDNF have been suggested to predispose to Alzheimer's disease, very little data are available on its association with cognitive function in general population. We...... evaluated the association between plasma BDNF levels and cognition in a representative population sample of ageing men and women. The subjects (n=1389) were participants of the Dose-Responses to Exercise Training (DR's EXTRA) Study and represent a random sample of Eastern Finnish people (684 men and 705...... women), 57-79 years of age at baseline of the study. Plasma BDNF levels were measured by enzyme-linked immunosorbent assay (ELISA). Cognitive function was evaluated using the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological test battery. Women had a higher mean...

  7. The role of BDNF in depression on the basis of its location in the neural circuitry

    Institute of Scientific and Technical Information of China (English)

    Hui YU; Zhe-yu CHEN

    2011-01-01

    Depression is one of the most prevalent and life-threatening forms of mental illnesses and the neural circuitry underlying depression remains incompletely understood. Most attention in the field has focused on hippocampal and frontal cortical regions for their roles in depression and antidepressant action. While these regions no doubt play important roles in the mental illness, there is compelling evi-dence that other brain regions are also involved. Brain-derived neurotrophic factor (BDNF) is broadly expressed in the developing and adult mammalian brain and has been implicated in development, neural regeneration, synaptic transmission, synaptic plasticity and neurogenesis. Recently BDNF has been shown to play an important role in the pathophysiology of depression, however there are con-troversial reports about the effects of BDNF on depression. Here, we present an overview of the current knowledge concerning BDNF actions and associated intracellular signaling in hippocampus, prefrontal cortex, nucleus accumbens (NAc) and amygdala as their rela-tion to depression.

  8. BDNF mediates improvements in executive function following a 1-year exercise intervention

    OpenAIRE

    Regina Lynn Leckie; Oberlin, Lauren E.; Voss, Michelle W.; Prakash, Ruchika S.; Amanda eSzabo-Reed; Laura eChaddock-Heyman; Phillips, Siobhan M.; Gothe, Neha P.; Emily eMailey; Victoria Jeanne Vieira-Potter; Martin, Stephen A.; Pence, Brandt D.; Mingkuan eLin; Raja eParasuraman; Greenwood, Pamela M.

    2014-01-01

    Executive function declines with age, but engaging in aerobic exercise may attenuate decline. One mechanism by which aerobic exercise may preserve executive function is through the up-regulation of brain-derived neurotropic factor (BDNF), which also declines with age. The present study examined BDNF as a mediator of the effects of a 1-year walking intervention on executive function in 90 older adults (mean age = 66.82). Participants were randomized to a stretching and toning control group or ...

  9. BDNF Plasma Level als Marker für Alzheimer in der VITA Studie

    OpenAIRE

    Altides, Anastasia Elisabeth

    2011-01-01

    HINTERGRUND: Der brain-derived neurotrophic factor (BDNF) reguliert die synaptische Plastizität und spielt somit eine wichtige Rolle in der Gedächtnisbildung und -erhaltung. Deswegen gibt es eingehende Untersuchungen dieses neurotrophischen Faktors in Bezug auf Demenzerkrankungen, vor allem der Alzheimer Demenz. In dieser Studie wurde nach einem Zusammenhang zwischen BDNF Blutplasmawerten und der Alzheimer Demenz in einer longitudinalen Kohortenstudie, der Vienna-Transdanube-Aging(VITA)-Studi...

  10. Comparative Effect of Treadmill Exercise on Mature BDNF Production in Control versus Stroke Rats

    OpenAIRE

    Quirié, Aurore; Hervieu, Marie; Garnier, Philippe; Demougeot, Céline; Mossiat, Claude; Bertrand, Nathalie; Martin, Alain; Marie, Christine; Prigent-Tessier, Anne

    2012-01-01

    Physical exercise constitutes an innovative strategy to treat deficits associated with stroke through the promotion of BDNF-dependent neuroplasticity. However, there is no consensus on the optimal intensity/duration of exercise. In addition, whether previous stroke changes the effect of exercise on the brain is not known. Therefore, the present study compared the effects of a clinically-relevant form of exercise on cerebral BDNF levels and localization in control versus stroke rats. For this ...

  11. The role of brain-derived neurotropic factor (BDNF) in stress-related brain disorders

    OpenAIRE

    Giese, Maria

    2013-01-01

    Evidence has been raised demonstrating the complex outcome of stress on the BDNF system and that the protein is a critical backbone in the functioning and well-being of the central nervous system. Several studies support the “neurotrophin hypothesis of depression”, which postulates that reduced brain levels of BDNF could contribute to atrophy and cell loss as observed in the hippocampus of depressed subjects. However, the precise mechanism underlying this down-regulation has not been fully un...

  12. A Longitudinal Study of BDNF Promoter Methylation and Depression in Breast Cancer

    OpenAIRE

    Kang, Hee-Ju; Kim, Jae-Min; Kim, Seon-Young; Kim, Sung-Wan; Shin, Il-Seon; Kim, Hye-Ran; Park, Min-Ho; Shin, Myung-Geun; Yoon, Jung-Han; Yoon, Jin-Sang

    2015-01-01

    Objective Brain-derived neurotrophic factor (BDNF) is investigated in depression related to medical disorders and its secretion is influenced by epigenetic factors. We investigated the association between BDNF promoter methylation and depression following mastectomy for breast cancer. Methods In total, 309 patients with breast cancer were evaluated 1 week after mastectomy, and 244 (79%) were followed up 1 year later. Depression was diagnosed (major or minor depressive disorder) according to D...

  13. Selective DNA Methylation of BDNF Promoter in Bipolar Disorder: Differences Among Patients with BDI and BDII

    OpenAIRE

    D'Addario, Claudio; Dell'Osso, Bernardo; Palazzo, Maria Carlotta; Benatti, Beatrice; Lietti, Licia; Cattaneo, Elisabetta; Galimberti, Daniela; Fenoglio, Chiara; Cortini, Francesca; Scarpini, Elio; Arosio, Beatrice; Di Francesco, Andrea; Di Benedetto, Manuela; Romualdi, Patrizia; Candeletti, Sanzio

    2012-01-01

    The etiology of bipolar disorder (BD) is still poorly understood, involving genetic and epigenetic mechanisms as well as environmental contributions. This study aimed to investigate the degree of DNA methylation at the promoter region of the brain-derived neurotrophic factor (BDNF) gene, as one of the candidate genes associated with major psychoses, in peripheral blood mononuclear cells isolated from 94 patients with BD (BD I=49, BD II=45) and 52 healthy controls. A significant BDNF gene expr...

  14. BDNF deficiency and young-adult methamphetamine induce sex-specific effects on prepulse inhibition regulation

    Directory of Open Access Journals (Sweden)

    Elizabeth E Manning

    2013-06-01

    Full Text Available Brain-derived neurotrophic factor (BDNF has been implicated in the pathophysiology of schizophrenia, yet its role in the development of specific symptoms is unclear. Methamphetamine (METH users have an increased risk of psychosis and schizophrenia, and METH-treated animals have been used extensively as a model to study the positive symptoms of schizophrenia. We investigated whether METH treatment in BDNF heterozygous mutant mice (HET has cumulative effects on sensorimotor gating, including the disruptive effects of psychotropic drugs. BDNF HETs and WT littermates were treated during young-adulthood with METH and, following a two-week break, prepulse inhibition (PPI was examined. At baseline, BDNF HETs showed reduced PPI compared to WT mice irrespective of METH pre-treatment. An acute challenge with amphetamine (AMPH disrupted PPI but male BDNF HETs were more sensitive to this effect, irrespective of METH pre-treatment. In contrast, female mice treated with METH were less sensitive to the disruptive effects of AMPH, and there were no effects of BDNF genotype. Similar changes were not observed in the response to an acute apomorphine or MK-801 challenge. These results show that genetically-induced reduction of BDNF caused changes in a behavioural endophenotype relevant to the positive symptoms of schizophrenia. However, major sex differences were observed in the effects of a psychotropic drug challenge on this behaviour. These findings suggest sex differences in the effects of BDNF depletion and METH treatment on the monoamine signaling pathways that regulate PPI. Given that these same pathways are thought to contribute to the expression of positive symptoms in schizophrenia, this work suggests that there may be significant sex differences in the pathophysiology underlying these symptoms. Elucidating these sex differences may be important for our understanding of the neurobiology of schizophrenia and developing better treatments strategies for the

  15. Prey from the eyes of predators: Color discriminability of aposematic and mimetic butterflies from an avian visual perspective.

    Science.gov (United States)

    Su, Shiyu; Lim, Matthew; Kunte, Krushnamegh

    2015-11-01

    Predation exerts strong selection on mimetic butterfly wing color patterns, which also serve other functions such as sexual selection. Therefore, specific selection pressures may affect the sexes and signal components differentially. We tested three predictions about the evolution of mimetic resemblance by comparing wing coloration of aposematic butterflies and their Batesian mimics: (a) females gain greater mimetic advantage than males and therefore are better mimics, (b) due to intersexual genetic correlations, sexually monomorphic mimics are better mimics than female-limited mimics, and (c) mimetic resemblance is better on the dorsal wing surface that is visible to predators in flight. Using a physiological model of avian color vision, we quantified mimetic resemblance from predators' perspective, which showed that female butterflies were better mimics than males. Mimetic resemblance in female-limited mimics was comparable to that in sexually monomorphic mimics, suggesting that intersexual genetic correlations did not constrain adaptive response to selection for female-limited mimicry. Mimetic resemblance on the ventral wing surface was better than that on the dorsal wing surface, implying stronger natural and sexual selection on ventral and dorsal surfaces, respectively. These results suggest that mimetic resemblance in butterfly mimicry rings has evolved under various selective pressures acting in a sex- and wing surface-specific manner.

  16. ProBDNF inhibits collective migration and chemotaxis of rat Schwann cells.

    Science.gov (United States)

    Ding, You-Quan; Li, Xuan-Yang; Xia, Guan-Nan; Ren, Hong-Yi; Zhou, Xin-Fu; Su, Bing-Yin; Qi, Jian-Guo

    2016-10-01

    Schwann cell migration, including collective migration and chemotaxis, is essential for the formation of coordinate interactions between Schwann cells and axons during peripheral nerve development and regeneration. Moreover, limited migration of Schwann cells imposed a serious obstacle on Schwann cell-astrocytes intermingling and spinal cord repair after Schwann cell transplantation into injured spinal cords. Recent studies have shown that mature brain-derived neurotrophic factor, a member of the neurotrophin family, inhibits Schwann cell migration. The precursor form of brain-derived neurotrophic factor, proBDNF, was expressed in the developing or degenerating peripheral nerves and the injured spinal cords. Since "the yin and yang of neurotrophin action" has been established as a common sense, proBDNF would be expected to promote Schwann cell migration. However, we found, in the present study, that exogenous proBDNF also inhibited in vitro collective migration and chemotaxis of RSC 96 cells, a spontaneously immortalized rat Schwann cell line. Moreover, proBDNF suppressed adhesion and spreading of those cells. At molecular level, proBDNF inhibits F-actin polymerization and focal adhesion dynamics in cultured RSC 96 cells. Therefore, our results suggested a special case against the classical opinion of "the yin and yang of neurotrophin action" and implied that proBDNF might modulate peripheral nerve development or regeneration and spinal cord repair through perturbing native or transplanted Schwann cell migration.

  17. proBDNF Attenuates Hippocampal Neurogenesis and Induces Learning and Memory Deficits in Aged Mice.

    Science.gov (United States)

    Chen, Jia; Li, Cheng-Ren; Yang, Heng; Liu, Juan; Zhang, Tao; Jiao, Shu-Sheng; Wang, Yan-Jiang; Xu, Zhi-Qiang

    2016-01-01

    Mature brain-derived neurotrophic factor has shown promotive effect on neural cells in rodents, including neural proliferation, differentiation, survival, and synaptic formation. Conversely, the precursor of brain-derived neurotrophic factor (proBDNF) has been emerging as a differing protein against its mature form, for its critical role in aging process and neurodegenerative diseases. In the present study, we investigated the role of proBDNF in neurogenesis in the hippocampal dentate gyrus of aged mice and examined the changes in mice learning and memory functions. The results showed that the newborn cells in the hippocampus revealed a significant decline in proBDNF-treated group compared with bovine serum albumin group, but an elevated level in anti-proBDNF group. During the maturation period, no significant change was observed in the proportions of phenotype of the newborn cells among the three groups. In water maze, proBDNF-treated mice had poorer scores in place navigation test and probe test, compared with those from any other group. Thus, we conclude that proBDNF attenuates neurogenesis in the hippocampus and induces the deficits in learning and memory functions of aged mice.

  18. Serum cortisol and BDNF in patients with major depression-effect of yoga.

    Science.gov (United States)

    Naveen, G H; Varambally, Shivarama; Thirthalli, Jagadisha; Rao, Mukund; Christopher, Rita; Gangadhar, B N

    2016-06-01

    Depression is associated with low serum Brain Derived Neurotrophic Factor (BDNF) and elevated levels of serum cortisol. Yoga practices have been associated with antidepressant effects, increase in serum BDNF, and reduction in serum cortisol. This study examined the association between serum BDNF and cortisol levels in drug-naïve patients with depression treated with antidepressants, yoga therapy, and both. Fifty-four drug-naïve consenting adult outpatients with Major Depression (32 males) received antidepressants only (n = 16), yoga therapy only (n = 19), or yoga with antidepressants (n = 19). Serum BDNF andcortisol levels were obtained before and after 3 months using a sandwich ELISA method. One-way ANOVA, Chi-square test, and Pearson's correlation tests were used for analysis. The groups were comparable at baseline on most parameters. Significant improvement in depression scores and serum BDNF levels, and reduction in serum cortisol in the yoga groups, have been described in previous reports. A significant negative correlation was observed between change in BDNF (pre-post) and cortisol (pre-post) levels in the yoga-only group (r = -0.59, p = 0.008). In conclusion, yoga may facilitate neuroplasticity through stress reduction in depressed patients. Further studies are needed to confirm the findings and delineate the pathways for these effects. PMID:27174729

  19. Effect of Mozart Music on Hippocampal Content of BDNF in Postnatal Rats

    Directory of Open Access Journals (Sweden)

    Mohsen Marzban

    2011-04-01

    Full Text Available Introduction: It has shown that listening to Mozart music can potentiate spatial tasks in human; and reduce seizure attacks in epileptic patients. A few studies have reported the effects of prenatal plus postpartum exposure of mice to the Mozart music on brain-drived neurotrophic factor (BDNF in the hippocampus. Here we investigated the effect of postpartum exposure to The Mozart music on BDNF concentration in the hippocampus of rat.Methods: Thirty male one day old newborn Wistar rats divided randomly in two equal experimental and control groups. Experimental group exposed to slow rhythm Mozart music (Mozart Sonata for two pianos KV 448, 6 hour per day; sound pressure levels, between 80 and 100 dB for 60 successive days. The control group was kept in separate room with housing conditions like experimental group except music exposure. After 60 days the rats were euthanized and hippocampuses extracted; then the content of BDNF protein was measured using ELISA sandwich method. Results: Data analysis revealed that rats exposed to Mozart Sonata music had significantly increased BDNF content in the hippocampus as compared to control rats (P±0.01. The concentrations of BDNF were 86.30±2.26 and 94.60 ±6.22 ng/g wet weight in control and music exposure groups respectively.Discussion: Exposure to the Mozart music early in life can increase the BDNF concentration in the hippocampus in rats.

  20. Brain-derived neurotrophic factor (BDNF) expression in normal and regenerating olfactory epithelium of Xenopus laevis.

    Science.gov (United States)

    Frontera, Jimena Laura; Cervino, Ailen Soledad; Jungblut, Lucas David; Paz, Dante Agustín

    2015-03-01

    Olfactory epithelium has the capability to continuously regenerate olfactory receptor neurons throughout life. Adult neurogenesis results from proliferation and differentiation of neural stem cells, and consequently, olfactory neuroepithelium offers an excellent opportunity to study neural regeneration and the factors involved in the maintenance and regeneration of all their cell types. We analyzed the expression of BDNF in the olfactory system under normal physiological conditions as well as during a massive regeneration induced by chemical destruction of the olfactory epithelium in Xenopus laevis larvae. We described the expression and presence of BDNF in the olfactory epithelium and bulb. In normal physiological conditions, sustentacular (glial) cells and a few scattered basal (stem) cells express BDNF in the olfactory epithelium as well as the granular cells in the olfactory bulb. Moreover, during massive regeneration, we demonstrated a drastic increase in basal cells expressing BDNF as well as an increase in BDNF in the olfactory bulb and nerve. Together these results suggest an important role of BDNF in the maintenance and regeneration of the olfactory system.

  1. Postnatal Administration of Allopregnanolone Modifies Glutamate Release but Not BDNF Content in Striatum Samples of Rats Prenatally Exposed to Ethanol

    Directory of Open Access Journals (Sweden)

    Roberto Yunes

    2015-01-01

    Full Text Available Ethanol consumption during pregnancy may induce profound changes in fetal CNS development. We postulate that some of the effects of ethanol on striatal glutamatergic transmission and neurotrophin expression could be modulated by allopregnanolone, a neurosteroid modulator of GABAA receptor activity. We describe the acute pharmacological effect of allopregnanolone (65 μg/kg, s.c. administered to juvenile male rats (day 21 of age on the corticostriatal glutamatergic pathway, in both control and prenatally ethanol-exposed rats (two ip injections of 2.9 g/kg in 24% v/v saline solution on gestational day 8. Prenatal ethanol administration decreased the K+-induced release of glutamate regarding the control group. Interestingly, this effect was reverted by allopregnanolone. Regarding BDNF, allopregnanolone decreases the content of this neurotrophic factor in the striatum of control groups. However, both ethanol alone and ethanol plus allopregnanolone treated animals did not show any change regarding control values. We suggest that prenatal ethanol exposure may produce an alteration of GABAA receptors which blocks the GABA agonist-like effect of allopregnanolone on rapid glutamate release, thus disturbing normal neural transmission. Furthermore, the reciprocal interactions found between GABAergic neurosteroids and BDNF could underlie mechanisms operating during the neuronal plasticity of fetal development.

  2. The Antidepressant Effect of Angelica sinensis Extracts on Chronic Unpredictable Mild Stress-Induced Depression Is Mediated via the Upregulation of the BDNF Signaling Pathway in Rats

    Directory of Open Access Journals (Sweden)

    Jun Shen

    2016-01-01

    Full Text Available Angelica sinensis (AS, a traditional Chinese herbal medicine, has pharmaceutical effects on menstrual illness, cerebrovascular diseases, cardiovascular diseases, and cognitive impairments. However, until recently, few studies had explored its antidepressant effect. The current study attempts to investigate the effect of AS extracts on chronic unpredictable mild stress- (CUMS- induced depression in rats. Male SD rats were exposed to a CUMS-inducing procedure for 5 weeks, resulting in rodent depressive behaviors that included reduced sucrose consumption and lessened sucrose preference ratios in sucrose preference test, prolonged immobility times and decreased struggling time in force swim test, and decreased locomotor activity in open field test. Moreover, the expression of brain derived neurotrophic factor (BDNF and the phosphorylation of cAMP-response element binding protein (CREB and extracellular signal-regulated protein kinase (ERK 1/2 were markedly decreased in the hippocampus in depressed rats. However, chronically treating the depressed rats with AS (1 g/kg normalized their depression-related behaviors and molecular profiles. In conclusion, in the present study, we show that AS extracts exerted antidepressant effects that were mediated by the BDNF signaling pathway: in AS-treated depressed rats, the expression of the BDNF protein and the phosphorylation of its downstream targets (ERK 1/2, CREB were upregulated in the hippocampus.

  3. Static spherically symmetric solutions in mimetic gravity: rotation curves and wormholes

    Science.gov (United States)

    Myrzakulov, Ratbay; Sebastiani, Lorenzo; Vagnozzi, Sunny; Zerbini, Sergio

    2016-06-01

    In this work, we analyse static spherically symmetric solutions in the framework of mimetic gravity, an extension of general relativity where the conformal degree of freedom of gravity is isolated in a covariant fashion. Here we extend previous works by considering, in addition, a potential for the mimetic field. An appropriate choice of such a potential allows for the reconstruction of a number of interesting cosmological and astrophysical scenarios. We explicitly show how to reconstruct such a potential for a general static spherically symmetric space-time. A number of applications and scenarios are then explored, among which are traversable wormholes. Finally, we analytically reconstruct potentials, which leads to solutions to the equations of motion featuring polynomial corrections to the Schwarzschild space-time. Accurate choices for such corrections could provide an explanation for the inferred flat rotation curves of spiral galaxies within the mimetic gravity framework, without the need for particle dark matter.

  4. The two faces of mimetic Horndeski gravity: disformal transformations and Lagrange multiplier

    CERN Document Server

    Arroja, Frederico; Karmakar, Purnendu; Matarrese, Sabino

    2015-01-01

    We show that very general scalar-tensor theories of gravity (including, e.g., Horndeski models) are generically invariant under disformal transformations. However there is a special subset, when the transformation is not invertible, that yields new equations of motion which are a generalization of the so-called "mimetic" dark matter theory recently introduced by Chamsedinne and Mukhanov. These new equations of motion can also be derived from an action containing an additional Lagrange multiplier field. The general mimetic scalar-tensor theory has the same number of derivatives in the equations of motion as the original scalar-tensor theory. As an application we show that the simplest mimetic scalar-tensor model is able to mimic the cosmological background of a flat FLRW model with an irrotational barotropic perfect fluid with any constant equation of state.

  5. BDNF-TrkB axis regulates migration of the lateral line primordium and modulates the maintenance of mechanoreceptor progenitors.

    Directory of Open Access Journals (Sweden)

    Eugene V Gasanov

    Full Text Available BDNF and its specialized receptor TrkB are expressed in the developing lateral line system of zebrafish, but their role in this organ is unknown. To tackle this problem in vivo, we used transgenic animals expressing fluorescent markers in different cell types of the lateral line and combined a BDNF gain-of-function approach by BDNF mRNA overexpression and by soaking embryos in a solution of BDNF, with a loss-of-function approach by injecting the antisence ntrk2b-morpholino and treating embryos with the specific Trk inhibitor K252a. Subsequent analysis demonstrated that the BDNF-TrkB axis regulates migration of the lateral line primordium. In particular, BDNF-TrkB influences the expression level of components of chemokine signaling including Cxcr4b, and the generation of progenitors of mechanoreceptors, at the level of expression of Atoh1a-Atp2b1a.

  6. Whole blood BDNF levels in healthy twins discordant for affective disorder: association to life events and neuroticism

    DEFF Research Database (Denmark)

    Trajkovska, V.; Vinberg, M.; Aznar, S.;

    2008-01-01

    BACKGROUND: Depression has been associated with decreased blood BDNF concentrations; but it is unclear if low blood BDNF levels are a state or a trait marker of depression. METHODS: We investigated blood BDNF concentrations in a twin population including both subjects highly predisposed...... and protected against affective disorder. Whole blood assessed for BDNF concentrations and correlated to risk status, neuroticism, and number of stressful life events. RESULTS: Between the groups, we found no significant difference in whole blood BDNF levels. Women at high-risk for depression who had...... experienced three or more recent stressful events (n=26) had decreased whole blood BDNF levels compared to high-risk women with two or less recent stressful events (n=35), 21.6+/-7.0 vs. 18.5+/-4.1 ng/ml, respectively, (p

  7. Synthesis of multivalent carbohydrate mimetics with aminopolyol end groups and their evaluation as L-selectin inhibitors

    Directory of Open Access Journals (Sweden)

    Joana Salta

    2015-05-01

    Full Text Available In this article a series of divalent and trivalent carbohydrate mimetics on the basis of an enantiopure aminopyran and of serinol is described. These aminopolyols are connected by amide bonds to carboxylic acid derived spacer units either by Schotten–Baumann acylation or by coupling employing HATU as reagent. The O-sulfation employing the SO3·DMF complex was optimized. It was crucial to follow this process by 700 MHz 1H NMR spectroscopy to ensure full conversion and to use a refined neutralization and purification protocol. Many of the compounds could not be tested as L-selectin inhibitor by SPR due to their insolubility in water, nevertheless, a divalent and a trivalent amide showed surprisingly good activities with IC50 values in the low micromolar range.

  8. Respective pharmacological features of neuropathic-like pain evoked by intrathecal BDNF versus sciatic nerve ligation in rats

    OpenAIRE

    M’Dahoma, Saïd; Barthélemy, Sandrine; Tromilin, Claire; Jeanson, Tiffany; Viguier, Florent; Michot, Benoit; Pezet, Sophie; Hamon, Michel; Bourgoin, Sylvie

    2015-01-01

    International audience Numerous reported data support the idea that Brain Derived Neurotrophic Factor (BDNF) is critically involved in both depression and comorbid pain. The possible direct effect of BDNF on pain mechanisms was assessed here and compared with behavioral/neurobiological features of neuropathic pain caused by chronic constriction injury to the sciatic nerve (CCI-SN). Sprague–Dawley male rats were either injected intrathecally with BDNF (3.0 ng i.t.) or subjected to unilatera...

  9. Targeted Disruption of the BDNF Gene Perturbs Brain and Sensory Neuron Development but Not Motor Neuron Development

    OpenAIRE

    Jones, Kevin R; Fariñas, Isabel; Backus, Carey; Reichardt, Louis F.

    1994-01-01

    Brain-derived neurotrophic factor (BDNF), a neurotrophin, enhances the survival and differentiation of several classes of neurons in vitro. To determine its essential functions, we have mutated the BDNF gene. Most homoxygote mutants die within 2 days after birth, but a fraction live for 2–4 weeks. These develop symptoms of nervous system dysfunction, including ataxia. The BDNF mutant homoxygotes have substantlaliy reduced numbers of cranlal and spinal sensory neurons. Although their central n...

  10. Reproductive isolation related to mimetic divergence in the poison frog Ranitomeya imitator

    DEFF Research Database (Denmark)

    Twomey, Evan; Vestergaard, Jacob Schack; Summers, Kyle

    2014-01-01

    study the Peruvian poison frog Ranitomeya imitator, a species that has undergone a mimetic radiation into four distinct morphs. Using a combination of colour–pattern analysis, landscape genetics and mate-choice experiments, we show that a mimetic shift in R. imitator is associated with a narrow...... phenotypic transition zone, neutral genetic divergence and assortative mating, suggesting that divergent selection to resemble different model species has led to a breakdown in gene flow between these two populations. These results extend the effects of mimicry on speciation into a vertebrate system...

  11. A Note on Schwarzschild de Sitter Black Holes in Mimetic $F(R)$ Gravity

    CERN Document Server

    Oikonomou, V K

    2016-01-01

    In this brief note we investigate the conditions under which a Schwarzschild de Sitter black hole spacetime is a solution of the mimetic $F(R)$ gravity with Lagrange multiplier and potential. As we demonstrate, the resulting mimetic $F(R)$ gravity is a slight modification of the ordinary $F(R)$ gravity case, however the resulting perturbation equations are not in all cases identical to the ordinary $F(R)$ gravity case. In the latter case, the perturbation equations are identical to the ones corresponding to the Reissner-Nordstr\\"{o}m anti-de Sitter black hole.

  12. A note on Schwarzschild-de Sitter black holes in mimetic F(R) gravity

    Science.gov (United States)

    Oikonomou, V. K.

    2016-05-01

    In this paper, we investigate the conditions under which a Schwarzschild-de Sitter black hole spacetime is a solution of the mimetic F(R) gravity with Lagrange multiplier and potential. As we demonstrate, the resulting mimetic F(R) gravity is a slight modification of the ordinary F(R) gravity case, however the resulting perturbation equations are not in all cases identical to the ordinary F(R) gravity case. In the latter case, the perturbation equations are identical to the ones corresponding to the Reissner-Nordström anti-de Sitter black hole.

  13. A Note on Schwarzschild de Sitter Black Holes in Mimetic $F(R)$ Gravity

    OpenAIRE

    Oikonomou, V.K.

    2016-01-01

    In this brief note we investigate the conditions under which a Schwarzschild de Sitter black hole spacetime is a solution of the mimetic $F(R)$ gravity with Lagrange multiplier and potential. As we demonstrate, the resulting mimetic $F(R)$ gravity is a slight modification of the ordinary $F(R)$ gravity case, however the resulting perturbation equations are not in all cases identical to the ordinary $F(R)$ gravity case. In the latter case, the perturbation equations are identical to the ones c...

  14. Synthesis of new enantiopure poly(hydroxyaminooxepanes as building blocks for multivalent carbohydrate mimetics

    Directory of Open Access Journals (Sweden)

    Léa Bouché

    2014-01-01

    Full Text Available New compounds with carbohydrate-similar structure (carbohydrate mimetics are presented in this article. Starting from enantiopure nitrones and lithiated TMSE-allene we prepared three 1,2-oxazine derivatives which underwent a highly stereoselective Lewis acid-induced rearrangement to give bicyclic products in good yield. Subsequent reductive transformations delivered a library of new poly(hydroxyaminooxepane derivatives. The crucial final palladium-catalyzed hydrogenolysis of the 1,2-oxazine moiety was optimized resulting in a reasonably efficient approach to a series of new seven-membered carbohydrate mimetics.

  15. Allosteric inhibition of factor XIa. Sulfated non-saccharide glycosaminoglycan mimetics as promising anticoagulants.

    Science.gov (United States)

    Al-Horani, Rami A; Gailani, David; Desai, Umesh R

    2015-08-01

    Recent development of sulfated non-saccharide glycosaminoglycan mimetics, especially sulfated pentagalloyl glucopyranoside (SPGG), as potent inhibitors of factor XIa (FXIa) (J. Med. Chem. 2013; 56:867-878 and J. Med. Chem. 2014; 57:4805-4818) has led to a strong possibility of developing a new line of factor XIa-based anticoagulants. In fact, SPGG represents the first synthetic, small molecule inhibitor that appears to bind in site remote from the active site. Considering that allosteric inhibition of FXIa is a new mechanism for developing a distinct line of anticoagulants, we have studied SPGG's interaction with FXIa with a goal of evaluating its pre-clinical relevance. Comparative inhibition studies with several glycosaminoglycans revealed the importance of SPGG's non-saccharide backbone. SPGG did not affect the activity of plasma kallikrein, activated protein C and factor XIIIa suggesting that SPGG-based anticoagulation is unlikely to affect other pathways connected with coagulation factors. SPGG's effect on APTT of citrated human plasma was also not dependent on antithrombin or heparin cofactor II. Interestingly, SPGG's anticoagulant potential was diminished by serum albumin as well as factor XI, while it could be reversed by protamine or polybrene, which implies possible avenues for developing antidote strategy. Studies with FXIa mutants indicated that SPGG engages Lys529, Arg530 and Arg532, but not Arg250, Lys252, Lys253 and Lys255. Finally, SPGG competes with unfractionated heparin, but not with polyphosphates and/or glycoprotein Ibα, for binding to FXIa. These studies enhance understanding on the first allosteric inhibitor of FXIa and highlight its value as a promising anticoagulant. PMID:25935648

  16. Cognitive dysfunction and epigenetic alterations of the BDNF gene are induced by social isolation during early adolescence.

    Science.gov (United States)

    Li, Man; Du, Wei; Shao, Feng; Wang, Weiwen

    2016-10-15

    Early life adversity, such as social isolation, causes a variety of changes to the development of cognitive abilities and the nervous system. Increasing evidence has shown that epigenetic modifications mediate gene-environment interactions throughout the lifespan. In this study, we investigated the effect of adolescent social isolation on cognitive behaviours and epigenetic alterations of the brain-derived neurotrophic factor (BDNF) gene. Male Sprague Dawley rats were randomly assigned to either group-reared or isolation-reared conditions during post-natal days (PNDs) 21-34. On PND 56, all rats underwent behavioural testing and were then sacrificed for biochemical testing. Adolescent social isolation induced impaired PPI. Regarding BDNF, the isolation-reared rats demonstrated increased BDNF mRNA levels, H3 acetylation at the BDNF gene and BDNF protein expression in the medial prefrontal cortex (mPFC). In contrast, the BDNF mRNA levels, H3 acetylation of the BDNF gene and BDNF protein expression were decreased in the hippocampus of the isolation-reared rats. The present study indicated that epigenetic regulation of BDNF may be one of the molecular mechanisms that mediated the cognitive dysfunction. Moreover, the interaction between the mPFC and hippocampus might play an important role in the regulation of cognitive behaviour. PMID:27435421

  17. The BDNF Val66Met polymorphism and plasma brain-derived neurotrophic factor levels in Han Chinese heroin-dependent patients.

    Science.gov (United States)

    Chen, Shiou-Lan; Lee, Sheng-Yu; Chang, Yun-Hsuan; Wang, Tzu-Yun; Chen, Shih-Heng; Chu, Chun-Hsien; Chen, Po See; Yang, Yen Kuang; Hong, Jau-Shyong; Lu, Ru-Band

    2015-02-02

    BDNF and its gene polymorphism may be important in synaptic plasticity and neuron survival, and may become a key target in the physiopathology of long-term heroin use. Thus, we investigated the relationships between brain-derived neurotrophic factor (BDNF) plasma concentrations and the BDNF Val66Met nucleotide polymorphism (SNP) in heroin-dependent patients. The pretreatment expression levels of plasma BDNF and the BDNF Val66Met SNP in 172 heroin-dependent patients and 102 healthy controls were checked. BDNF levels were significantly lower in patients (F = 52.28, p BDNF levels significantly different between Met/Met, Met/Val, and Val/Val carriers in each group, which indicated that the BDNF Val66Met SNP did not affect plasma BDNF levels in our participants. In heroin-dependent patients, plasma BDNF levels were negatively correlated with the length of heroin dependency. Long-term (>15 years) users had significantly lower plasma BDNF levels than did short-term (BDNF concentration in habitual heroin users are not affected by BDNF Val66Met gene variants, but by the length of the heroin dependency.

  18. Effects of Ethanol on the Expression Level of Various BDNF mRNA Isoforms and Their Encoded Protein in the Hippocampus of Adult and Embryonic Rats

    Directory of Open Access Journals (Sweden)

    Shahla Shojaei

    2015-12-01

    Full Text Available We aimed to compare the effects of oral ethanol (Eth alone or combined with the phytoestrogen resveratrol (Rsv on the expression of various brain-derived neurotrophic factor (BDNF transcripts and the encoded protein pro-BDNF in the hippocampus of pregnant and embryonic rats. A low (0.25 g/kg body weight (BW/day dose of Eth produced an increase in the expression of BDNF exons I, III and IV and a decrease in that of the exon IX in embryos, but failed to affect BDNF transcript and pro-BDNF protein expression in adults. However, co-administration of Eth 0.25 g/kg·BW/day and Rsv led to increased expression of BDNF exons I, III and IV and to a small but significant increase in the level of pro-BDNF protein in maternal rats. A high (2.5 g/kg·BW/day dose of Eth increased the expression of BDNF exons III and IV in embryos, but it decreased the expression of exon IX containing BDNF mRNAs in the maternal rats. While the high dose of Eth alone reduced the level of pro-BDNF in adults, it failed to change the levels of pro-BDNF in embryos. Eth differentially affects the expression pattern of BDNF transcripts and levels of pro-BDNF in the hippocampus of both adult and embryonic rats.

  19. BDNF genotype interacts with motor-function to influence rehabilitation responsiveness post-stroke

    Directory of Open Access Journals (Sweden)

    Christine T Shiner

    2016-05-01

    Full Text Available Background. Persistent motor impairment is common but highly heterogeneous post-stroke. Genetic polymorphisms, including those identified on the brain derived neurotrophic factor (BDNF and apolipoprotein E (APOE genes, may contribute to this variability by limiting the capacity for use-dependent neuroplasticity, and hence rehabilitation responsiveness.Objective. To determine whether BDNF and APOE genotypes influence motor improvement facilitated by post-stroke upper-limb rehabilitation. Methods. BDNF Val66Met and APOE isoform genotypes were determined using leukocyte DNA for 55 community-dwelling patients 2-123 months post-stroke. All patients completed a dose-matched upper-limb rehabilitation program of either Wii-based Movement Therapy or Constraint-induced Movement Therapy. Upper-limb motor-function was assessed pre- and post-therapy using a suite of functional measures. Results. Motor-function improved for all patients post-therapy, with no difference between therapy groups. In the pooled data, there was no significant effect of BDNF or APOE genotype on motor-function at baseline, or following the intervention. However, a significant interaction between the level of residual motor-function and BDNF genotype was identified (p=0.029, whereby post-therapy improvement was significantly less for Met allele carriers with moderate and high, but not low motor-function. There was no significant association between APOE genotype and therapy outcomes. Conclusions. This study identified a novel interaction between the BDNF Val66Met polymorphism, motor-function status and the magnitude of improvement with rehabilitation in chronic stroke. This polymorphism does not preclude, but may reduce, the magnitude of motor improvement with therapy, particularly for patients with higher but not lower residual motor-function. BDNF genotype should be considered in the design and interpretation of clinical trials.

  20. Mesenchymal stem cell responses to bone-mimetic electrospun matrices composed of polycaprolactone, collagen I and nanoparticulate hydroxyapatite.

    Directory of Open Access Journals (Sweden)

    Matthew C Phipps

    Full Text Available The performance of biomaterials designed for bone repair depends, in part, on the ability of the material to support the adhesion and survival of mesenchymal stem cells (MSCs. In this study, a nanofibrous bone-mimicking scaffold was electrospun from a mixture of polycaprolactone (PCL, collagen I, and hydroxyapatite (HA nanoparticles with a dry weight ratio of 50/30/20 respectively (PCL/col/HA. The cytocompatibility of this tri-component scaffold was compared with three other scaffold formulations: 100% PCL (PCL, 100% collagen I (col, and a bi-component scaffold containing 80% PCL/20% HA (PCL/HA. Scanning electron microscopy, fluorescent live cell imaging, and MTS assays showed that MSCs adhered to the PCL, PCL/HA and PCL/col/HA scaffolds, however more rapid cell spreading and significantly greater cell proliferation was observed for MSCs on the tri-component bone-mimetic scaffolds. In contrast, the col scaffolds did not support cell spreading or survival, possibly due to the low tensile modulus of this material. PCL/col/HA scaffolds adsorbed a substantially greater quantity of the adhesive proteins, fibronectin and vitronectin, than PCL or PCL/HA following in vitro exposure to serum, or placement into rat tibiae, which may have contributed to the favorable cell responses to the tri-component substrates. In addition, cells seeded onto PCL/col/HA scaffolds showed markedly increased levels of phosphorylated FAK, a marker of integrin activation and a signaling molecule known to be important for directing cell survival and osteoblastic differentiation. Collectively these results suggest that electrospun bone-mimetic matrices serve as promising degradable substrates for bone regenerative applications.

  1. Dramatic nano-fluidic properties of carbon nanotube membranes as a platform for protein channel mimetics

    Science.gov (United States)

    Hinds, Bruce

    2013-03-01

    Carbon nanotubes have three key attributes that make them of great interest for novel membrane applications: 1) atomically flat graphite surface allows for ideal fluid slip boundary conditions and extremely fast flow rates 2) the cutting process to open CNTs inherently places functional chemistry at CNT core entrance for chemical selectivity and 3) CNT are electrically conductive allowing for electrochemical reactions and application of electric fields gradients at CNT tips. Pressure driven flux of a variety of solvents (H2O, hexane, decane ethanol, methanol) are 4-5 orders of magnitude higher than conventional Newtonian flow [Nature 2005, 438, 44] due to atomically flat graphite planes inducing nearly ideal slip conditions. However this is eliminated with selective chemical functionalization [ACS Nano 2011 5(5) 3867-3877] needed to give chemical selectivity. These unique properties allow us to explore the hypothesis of producing ``Gatekeeper'' membranes that mimic natural protein channels to actively pump through rapid nm-scale channels. With anionic tip functionality strong electroosmotic flow is induced by unimpeded cation flow with similar 10,000 fold enhancements [Nature Nano 2012 7(2) 133-39]. With enhanced power efficiency, carbon nanotube membranes were employed as the active element of a switchable transdermal drug delivery device that can facilitate more effective treatments of drug abuse and addiction. Recently methods to deposit Pt monolayers on CNT surface have been developed making for highly efficient catalytic platforms. Discussed are other applications of CNT protein channel mimetics, for large area robust engineering platforms, including water purification, flow battery energy storage, and biochemical/biomass separations. DOE EPSCoR (DE-FG02-07ER46375) and DARPA, W911NF-09-1-0267

  2. Temporally degradable collagen-mimetic hydrogels tuned to chondrogenesis of human mesenchymal stem cells.

    Science.gov (United States)

    Parmar, Paresh A; Skaalure, Stacey C; Chow, Lesley W; St-Pierre, Jean-Philippe; Stoichevska, Violet; Peng, Yong Y; Werkmeister, Jerome A; Ramshaw, John A M; Stevens, Molly M

    2016-08-01

    Tissue engineering strategies for repairing and regenerating articular cartilage face critical challenges to recapitulate the dynamic and complex biochemical microenvironment of native tissues. One approach to mimic the biochemical complexity of articular cartilage is through the use of recombinant bacterial collagens as they provide a well-defined biological 'blank template' that can be modified to incorporate bioactive and biodegradable peptide sequences within a precisely defined three-dimensional system. We customized the backbone of a Streptococcal collagen-like 2 (Scl2) protein with heparin-binding, integrin-binding, and hyaluronic acid-binding peptide sequences previously shown to modulate chondrogenesis and then cross-linked the recombinant Scl2 protein with a combination of matrix metalloproteinase 7 (MMP7)- and aggrecanase (ADAMTS4)-cleavable peptides at varying ratios to form biodegradable hydrogels with degradation characteristics matching the temporal expression pattern of these enzymes in human mesenchymal stem cells (hMSCs) during chondrogenesis. hMSCs encapsulated within the hydrogels cross-linked with both degradable peptides exhibited enhanced chondrogenic characteristics as demonstrated by gene expression and extracellular matrix deposition compared to the hydrogels cross-linked with a single peptide. Additionally, these combined peptide hydrogels displayed increased MMP7 and ADAMTS4 activities and yet increased compression moduli after 6 weeks, suggesting a positive correlation between the degradation of the hydrogels and the accumulation of matrix by hMSCs undergoing chondrogenesis. Our results suggest that including dual degradation motifs designed to respond to enzymatic activity of hMSCs going through chondrogenic differentiation led to improvements in chondrogenesis. Our hydrogel system demonstrates a bimodal enzymatically degradable biological platform that can mimic native cellular processes in a temporal manner. As such, this novel

  3. Blockade of Cannabinoid CB1 receptor attenuates the acquisition of morphine-induced conditioned place preference along with a downregulation of ERK, CREB phosphorylation, and BDNF expression in the nucleus accumbens and hippocampus.

    Science.gov (United States)

    Zhang, Jianbo; Wang, Na; Chen, Bo; Wang, Yi'nan; He, Jing; Cai, Xintong; Zhang, Hongbo; Wei, Shuguang; Li, Shengbin

    2016-09-01

    Cannabinoid CB1 receptor (CB1R) is highly expressed in the mesocorticolimbic system and associated with drug craving and relapse. Clinical trials suggest that CB1R antagonists may represent new therapies for drug addiction. However, the downstream signaling of CB1R is not fully elucidated. In the present study, we investigated the relationship between CB1R and the extracellular signal-regulated kinase (ERK), cAMP response element-binding protein (CREB), brain-derived neurotrophic factor (BDNF) signaling in the nucleus accumbens (NAc) and hippocampus in morphine-induced conditioned place preference (CPP), which is used to assess the morphine-induced reward memory. The protein level of CB1R, ERK, CREB, and BDNF were detected by western blotting. Additionally, a CB1R antagonist, AM251, was used to study whether blockade of CB1R altered the CPP and above-mentioned molecules. We found an increase of CB1R expression in the NAc and hippocampus of the mice following morphine CPP, but not those after repeated morphine in home cage without context exposure (NO-CPP). Both morphine CPP and NO-CPP induced an upregulation of ERK, CREB phosphorylation and BDNF expression. Furthermore, pretreatment with AM251 before morphine attenuated the CPP acquisition and CB1R expression as well as the activation of ERK-CREB-BDNF cascade. Collectively, these findings demonstrate that (1) Repeated morphine with context exposures but not merely the pharmacological effects of morphine increased CB1R expression both in the NAc and hippocampus. (2) CB1R antagonist mediated blockade of ERK-CREB-BDNF signaling activation in the NAc and hippocampus may be an important mechanism underlying the attenuation of morphine CPP. PMID:27461790

  4. Reissner–Nordström Anti-de Sitter Black Holes in Mimetic F(R) Gravity

    Science.gov (United States)

    Oikonomou, V. K.

    2016-05-01

    In this paper we study under which conditions the Reissner-Nordstr\\"om-anti de Sitter black hole can be a solution of the vacuum mimetic $F(R)$ gravity with Lagrange multiplier and mimetic scalar potential. As we demonstrate, the resulting picture in the mimetic $F(R)$ gravity case, is different in comparison to the ordinary $F(R)$ gravity case, with the two descriptions resulting to a different set of constraints that need to hold true. We also investigate the metric perturbations in the mimetic $F(R)$ gravity case, for the Reissner-Nordstr\\"om-anti de Sitter black hole metric, at first order of the perturbed variables. Interestingly enough, the resulting equations are identical to the ones corresponding to the ordinary $F(R)$ gravity Reissner-Nordstr\\"om-anti de Sitter black hole, at least at first order. We attribute this feature to the particular form of the Reissner-Nordstr\\"om-anti de Sitter metric, and we speculate for which cases there could be differences between the mimetic and non-mimetic case. Since the perturbation equations are the same for the two cases, it is possible to have black hole instabilities in the mimetic $F(R)$ gravity case too, which can be interpreted as anti-evaporation of the black hole.

  5. Brain-Derived Neurotrophic Factor (BDNF protein levels in anxiety disorders: systematic review and meta-regression analysis

    Directory of Open Access Journals (Sweden)

    Sharain eSuliman

    2013-07-01

    Full Text Available Background: Brain-Derived Neurotrophic Factor (BDNF is a neurotrophin that is involved in the synaptic plasticity and survival of neurons. BDNF is believed to be involved in the pathogenesis of several neuropsychiatric disorders. As findings of BDNF levels in the anxiety disorders have been inconsistent, we undertook to conduct a systematic review and meta-analysis of studies that assessed BDNF protein levels in anxiety disorders. Methods: We conducted the review using electronic databases and searched reference lists of relevant articles for any further studies. Studies that measured BDNF protein levels in any anxiety disorder and compared these to a control group were included. Effect sizes of the differences in BDNF levels between anxiety disorder and control groups were calculated. Results: Eight studies with a total of 1179 participants were included. Initial findings suggested that BDNF levels were lower in individuals with any anxiety disorder compared to those without (Standard Mean Difference [SMD]=-0.94 [-1.75, -0.12], p≤0.05. This, however, differed with regards to source of BDNF protein (plasma: SMD=-1.31 [-1.69, -0.92], p≤0.01; serum: SMD=-1.06 [-2.27, 0.16], p≥0.01 and type of anxiety disorder (PTSD: SMD=-0.05 [-1.66, 1.75], p≥0.01; OCD: SMD=-2.33 [-4.21, -0.45], p≤0.01. Conclusion: Although BDNF levels appear to be reduced in individuals with an anxiety disorder, this is not consistent across the various anxiety disorders and may largely be explained by the significantly lowered BDNF levels found in OCD. Results further appear to be mediated by differences in sampling methods. Findings are, however, limited by the lack of research in this area, and given the potential for BDNF as a biomarker of anxiety disorders it would be useful to clarify the relationship further.

  6. Aspects of late-time evolution in mimetic F(R) gravity

    Science.gov (United States)

    Oikonomou, V. K.

    2016-09-01

    We demonstrate how to describe in an unified way early and late-time acceleration in the context of mimetic F(R) gravity. As we show, an exponential F(R) gravity model has appealing features, with regard to unification and we perform an analysis of the late-time evolution. The resulting picture is interesting since in the mimetic case, certain pathologies of some ordinary F(R) models are remedied in a consistent way, owing to the presence of the mimetic potential and the Lagrange multiplier. We quantify the late-time evolution analysis by studying the scaled dark energy density, the dark energy equation of state and the total effective equation of state, and as we show the late-time evolution is crucially affected by the functional form of the F(R) gravity. It is intriguing that the most appealing case corresponds to the exponential F(R) gravity which unifies late- and early-time acceleration. Finally, we study the behavior of the effective gravitational constant and the growth factor, and as we show, significant differences between the mimetic and ordinary F(R) exponential model are spotted in the growth factor.

  7. Incretin mimetics: a novel therapeutic option for patients with type 2 diabetes - a review

    DEFF Research Database (Denmark)

    Hansen, Katrine Bilberg; Vilsbøll, Tina; Knop, Filip K

    2010-01-01

    factors such as weight loss, decrease in blood pressure and changes in lipid profile. Current clinical data on the two available incretin mimetics, exenatide and liraglutide, are evaluated in this review, focusing on pharmacology, efficacy, safety and tolerability. The review is built on a systematic Pub...

  8. Gramicidin S derivatives containing cis- and trans-morpholine amino acids (MAAS) as turn mimetics

    NARCIS (Netherlands)

    Kapoerchan, V.V.; Spalburg, E.; Neeling, A.J. de; Mars-Groenendijk, R.H.; Noort, D.; Otero, J.M. de; Ferraces-Casais, P.; Llamas-Saiz, A.L.; Raaij, M.J. van; Doorn, J. van; Marel, G.A. van der; Overkleeft, H.S.; Overhand, M.

    2010-01-01

    The cyclic decapeptide gramicidin S (GS) was used as a model for the evaluation of four turn mimetics. For this purpose, one of the D-Phe-Pro two-residue turn motifs in the rigid cyclic β-hairp0in structure of GS was replaced with morpholine amino acids (MAA 2-5), differing in stereochemistry and le

  9. Application of Mn(Ⅱ) as a Mimetic Enzyme of Horseradish Peroxidase

    Institute of Scientific and Technical Information of China (English)

    Ai Xia HAN; Li Hong NIU; Rui CHANG; Fu Shi ZHANG

    2005-01-01

    In this study, Mn( Ⅱ ) as a mimetic enzyme of horseradish peroxidase (HRP) was applied to the determination of hydrogen peroxide (H2O2). The method introduced in this paper is based on Mn(Ⅱ)'s catalytic effect on the oxidation of 4-aminoantipyrine(4-AAP) with modified Trinder's reagent N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3, 5-dimethoxyaniline(DAOS) by H2O2.By coupling this mimetic catalytic reaction with the catalytic reaction of glucose oxidase (GOD),glucose can be detected. Under optimum conditions, the calibration graphs for the determination of H2O2 and glucose are in the range of 1.0×10-3-1.0×10-1 mol/L and 1.0×10-3-14×10-3 mol/L respectively. The detection limit is 5.9×10-4 mol/L for H2O2 and is 9.2×10-4 mol/L for glucose.The feasibility of Mn ( Ⅱ ) as a HRP mimetic enzyme in practical clinical analysis has been proven in the determination of glucose in human serum. So far, Mn ( Ⅱ ) is the simplest and the most inexpensive mimetic enzyme.

  10. BDNF Val66Met Polymorphism Is Associated with Self-Reported Empathy.

    Science.gov (United States)

    Taschereau-Dumouchel, Vincent; Hétu, Sébastien; Bagramian, Anaït; Labrecque, Alexandre; Racine, Marion; Chagnon, Yvon C; Jackson, Philip L

    2016-01-01

    Empathy is an important driver of human social behaviors and presents genetic roots that have been studied in neuroimaging using the intermediate phenotype approach. Notably, the Val66Met polymorphism of the Brain-derived neurotrophic factor (BDNF) gene has been identified as a potential target in neuroimaging studies based on its influence on emotion perception and social cognition, but its impact on self-reported empathy has never been documented. Using a neurogenetic approach, we investigated the association between the BDNF Val66Met polymorphism and self-reported empathy (Davis' Interpersonal Reactivity Index; IRI) in a sample of 110 young adults. Our results indicate that the BDNF genotype is significantly associated with the linear combination of the four facets of the IRI, one of the most widely used self-reported empathy questionnaire. Crucially, the effect of BDNF Val66Met goes beyond the variance explained by two polymorphisms of the oxytocin transporter gene previously associated with empathy and its neural underpinnings (OXTR rs53576 and rs2254298). These results represent the first evidence suggesting a link between the BDNF gene and self-reported empathy and warrant further studies of this polymorphism due to its potential clinical significance.

  11. BDNF modifies hippocampal KCC2 and NKCC1 expression in a temporal lobe epilepsy model.

    Science.gov (United States)

    Eftekhari, Sanaz; Mehrabi, Soraya; Soleimani, Mansooreh; Hassanzadeh, Gholamreza; Shahrokhi, Amene; Mostafavi, Hossein; Hayat, Parisa; Barati, Mahmood; Mehdizadeh, Hajar; Rahmanzadeh, Reza; Hadjighassem, Mahmoud Reza; Joghataei, Mohammad Taghi

    2014-01-01

    Excitatory GABA actions, induced by altered expression of chloride transporters (KCC2/NKCC1), can contribute to seizure generation in temporal lobe epilepsy. In the present study, we evaluated whether BDNF administration can affect KCC2/NKCC1 expression, ictogenesis and behavioral alterations in this paradigm. Status epilepticus was induced in male rats with pilocarpine, followed by a treatment of either a single high dose or multiple injections of BDNF during the latent phase of temporal lobe epilepsy. Chloride transporters expression, spontaneous recurrent seizures, and hyperexcitability post-seizural behaviors were evaluated after treatment. NKCC1 protein expression was markedly upregulated, whereas that of KCC2 was significantly downregulated in epileptic hippocampi compared to intact controls. Application of BDNF (both single high dose and multiple injections) increased KCC2 expression in epileptic hippocampi, while NKCC1 expression was downregulated exclusively by the single high dose injection of BDNF. Development of spontaneous recurrent seizures was delayed but not prevented by the treatment, and hyperexcitability behaviors were ameliorated for a short period of time. To prevent GABA-A mediated depolarization and design appropriate treatment strategies for temporal lobe epilepsy, chloride transporters can be considered as a target. Future studies are warranted to investigate any possible therapeutic effects of BDNF via altering chloride transporters expression.

  12. Neuroprotection, Growth Factors and BDNF-TrkB Signalling in Retinal Degeneration

    Science.gov (United States)

    Kimura, Atsuko; Namekata, Kazuhiko; Guo, Xiaoli; Harada, Chikako; Harada, Takayuki

    2016-01-01

    Neurotrophic factors play key roles in the development and survival of neurons. The potent neuroprotective effects of neurotrophic factors, including brain-derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), glial cell-line derived neurotrophic factor (GDNF) and nerve growth factor (NGF), suggest that they are good therapeutic candidates for neurodegenerative diseases. Glaucoma is a neurodegenerative disease of the eye that causes irreversible blindness. It is characterized by damage to the optic nerve, usually due to high intraocular pressure (IOP), and progressive degeneration of retinal neurons called retinal ganglion cells (RGCs). Current therapy for glaucoma focuses on reduction of IOP, but neuroprotection may also be beneficial. BDNF is a powerful neuroprotective agent especially for RGCs. Exogenous application of BDNF to the retina and increased BDNF expression in retinal neurons using viral vector systems are both effective in protecting RGCs from damage. Furthermore, induction of BDNF expression by agents such as valproic acid has also been beneficial in promoting RGC survival. In this review, we discuss the therapeutic potential of neurotrophic factors in retinal diseases and focus on the differential roles of glial and neuronal TrkB in neuroprotection. We also discuss the role of neurotrophic factors in neuroregeneration. PMID:27657046

  13. Potential antidepressant properties of cysteamine on hippocampal BDNF levels and behavioral despair in mice.

    Science.gov (United States)

    Shieh, Chu-Hsin; Hong, Chen-Jee; Huang, Yn-Ho; Tsai, Shih-Jen

    2008-08-01

    Several studies have demonstrated that antidepressants increase central brain-derived neurotrophic factor (BDNF) levels, suggesting that BDNF signaling is important for the therapeutic mechanism of antidepressants. Recent work has found that cysteamine and its related agent, cystamine, are neuroprotective in Huntington's disease mice, and act by enhancing the secretion of central BDNF. In the present study, the potential antidepressant effects of cysteamine were examined by behavioral paradigms and biochemical assay. Male BALB/CByJ mice were given a single dose of normal saline, 10 mg/kg of imipramine or either 50, 100 or 200 mg/kg of cysteamine (i.p.) 30 min before undergoing the forced-swimming test (FST) or the tail suspension test (TST). Other groups of mice treated with the same drugs and doses, without behavioral tests, were sacrificed for hippocampal BDNF measurements. We found that, compared with the control group, the cysteamine 200-mg/kg group showed a significant reduction in immobility time in the FST (Pcysteamine 200-mg/kg group (Pcysteamine may possess an antidepressant-like effect, which may be mediated by increasing central BDNF levels. PMID:18582526

  14. Substrate-Independent Robust and Heparin-Mimetic Hydrogel Thin Film Coating via Combined LbL Self-Assembly and Mussel-Inspired Post-Cross-linking.

    Science.gov (United States)

    Ma, Lang; Cheng, Chong; He, Chao; Nie, Chuanxiong; Deng, Jie; Sun, Shudong; Zhao, Changsheng

    2015-12-01

    In this work, we designed a robust and heparin-mimetic hydrogel thin film coating via combined layer-by-layer (LbL) self-assembly and mussel-inspired post-cross-linking. Dopamine-grafted heparin-like/-mimetic polymers (DA-g-HepLP) with abundant carboxylic and sulfonic groups were synthesized by the conjugation of adhesive molecule, DA, which exhibited substrate-independent adhesive affinity to various solid surfaces because of the formation of irreversible covalent bonds. The hydrogel thin film coated substrates were prepared by a three-step reaction: First, the substrates were coated with DA-g-HepLP to generate negatively charged surfaces. Then, multilayers were obtained via LbL coating of chitosan and the DA-g-HepLP. Finally, the noncovalent multilayers were oxidatively cross-linked by NaIO4. Surface ATR-FTIR and XPS spectra confirmed the successful fabrication of the hydrogel thin film coatings onto membrane substrates; SEM images revealed that the substrate-independent coatings owned 3D porous morphology. The soaking tests in highly alkaline, acid, and concentrated salt solutions indicated that the cross-linked hydrogel thin film coatings owned high chemical resistance. In comparison, the soaking tests in physiological solution indicated that the cross-linked hydrogel coatings owned excellent long-term stability. The live/dead cell staining and morphology observations of the adhered cells revealed that the heparin-mimetic hydrogel thin film coated substrates had low cell toxicity and high promotion ability for cell proliferation. Furthermore, systematic in vitro investigations of protein adsorption, platelet adhesion, blood clotting, and blood-related complement activation confirmed that the hydrogel film coated substrates showed excellent hemocompatibility. Both the results of inhibition zone and bactericidal activity indicated that the gentamycin sulfate loaded hydrogel thin films had significant inhibition capability toward both Escherichia coli and

  15. Viral depletion of VTA BDNF in rats modulates social behavior, consequences of intermittent social defeat stress, and long-term weight regulation

    OpenAIRE

    Fanous, Sanya; Terwilliger, Ernest F; Hammer, Ronald P.; Nikulina, Ella M.

    2011-01-01

    Mesolimbic brain-derived neurotrophic factor (BDNF) is implicated in sustained behavioral changes following chronic social stress, and its depletion may reduce susceptibility to such behavioral alterations. Enhanced mesolimbic BDNF is proposed as pro-depressive and anhedonic, while depleting ventral tegmetal area (VTA) BDNF increases weight by enhancing hedonic eating. Here, we questioned whether depletion of VTA BDNF would alleviate social defeat stress-induced deficits in weight regulation,...

  16. Reissner–Nordström Anti-de Sitter Black Holes in Mimetic F(R) Gravity

    OpenAIRE

    Oikonomou, V.K.

    2016-01-01

    In this paper we study under which conditions the Reissner-Nordstr\\"om-anti de Sitter black hole can be a solution of the vacuum mimetic $F(R)$ gravity with Lagrange multiplier and mimetic scalar potential. As we demonstrate, the resulting picture in the mimetic $F(R)$ gravity case, is different in comparison to the ordinary $F(R)$ gravity case, with the two descriptions resulting to a different set of constraints that need to hold true. We also investigate the metric perturbations in the mim...

  17. Structure of the nociceptin/orphanin FQ receptor in complex with a peptide mimetic

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Aaron A.; Liu, Wei; Chun, Eugene; Katritch, Vsevolod; Wu, Huixian; Vardy, Eyal; Huang, Xi-Ping; Trapella, Claudio; Guerrini, Remo; Calo, Girolamo; Roth, Bryan L.; Cherezov, Vadim; Stevens, Raymond C. (Ferrara); (Scripps); (UNC)

    2012-07-11

    Members of the opioid receptor family of G-protein-coupled receptors (GPCRs) are found throughout the peripheral and central nervous system, where they have key roles in nociception and analgesia. Unlike the 'classical' opioid receptors, {delta}, {kappa} and {mu} ({delta}-OR, {kappa}-OR and {mu}-OR), which were delineated by pharmacological criteria in the 1970s and 1980s, the nociceptin/orphanin FQ (N/OFQ) peptide receptor (NOP, also known as ORL-1) was discovered relatively recently by molecular cloning and characterization of an orphan GPCR. Although it shares high sequence similarity with classical opioid GPCR subtypes ({approx}60%), NOP has a markedly distinct pharmacology, featuring activation by the endogenous peptide N/OFQ, and unique selectivity for exogenous ligands. Here we report the crystal structure of human NOP, solved in complex with the peptide mimetic antagonist compound-24 (C-24) (ref. 4), revealing atomic details of ligand-receptor recognition and selectivity. Compound-24 mimics the first four amino-terminal residues of the NOP-selective peptide antagonist UFP-101, a close derivative of N/OFQ, and provides important clues to the binding of these peptides. The X-ray structure also shows substantial conformational differences in the pocket regions between NOP and the classical opioid receptors {kappa} (ref. 5) and {mu} (ref. 6), and these are probably due to a small number of residues that vary between these receptors. The NOP-compound-24 structure explains the divergent selectivity profile of NOP and provides a new structural template for the design of NOP ligands.

  18. Persistent inflammation-induced up-regulation of brain-derived neurotrophic factor (BDNF) promotes synaptic delivery of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor GluA1 subunits in descending pain modulatory circuits.

    Science.gov (United States)

    Tao, Wenjuan; Chen, Quan; Zhou, Wenjie; Wang, Yunping; Wang, Lu; Zhang, Zhi

    2014-08-01

    The enhanced AMPA receptor phosphorylation at GluA1 serine 831 sites in the central pain-modulating system plays a pivotal role in descending pain facilitation after inflammation, but the underlying mechanisms remain unclear. We show here that, in the rat brain stem, in the nucleus raphe magnus, which is a critical relay in the descending pain-modulating system of the brain, persistent inflammatory pain induced by complete Freund adjuvant (CFA) can enhance AMPA receptor-mediated excitatory postsynaptic currents and the GluA2-lacking AMPA receptor-mediated rectification index. Western blot analysis showed an increase in GluA1 phosphorylation at Ser-831 but not at Ser-845. This was accompanied by an increase in distribution of the synaptic GluA1 subunit. In parallel, the level of histone H3 acetylation at bdnf gene promoter regions was reduced significantly 3 days after CFA injection, as indicated by ChIP assays. This was correlated with an increase in BDNF mRNA levels and BDNF protein levels. Sequestering endogenous extracellular BDNF with TrkB-IgG in the nucleus raphe magnus decreased AMPA receptor-mediated synaptic transmission and GluA1 phosphorylation at Ser-831 3 days after CFA injection. Under the same conditions, blockade of TrkB receptor functions, phospholipase C, or PKC impaired GluA1 phosphorylation at Ser-831 and decreased excitatory postsynaptic currents mediated by GluA2-lacking AMPA receptors. Taken together, these results suggest that epigenetic up-regulation of BDNF by peripheral inflammation induces GluR1 phosphorylation at Ser-831 sites through activation of the phospholipase C-PKC signaling cascade, leading to the trafficking of GluA1 to pain-modulating neuronal synapses.

  19. 何首乌对衰老大鼠海马BDNF mRNA表达的影响%Influence of Polygonum Multiflorum on The BDNF mRNA of Hippocampus in The Senile Rat

    Institute of Scientific and Technical Information of China (English)

    李怡秋; 谭红; 李芳芳; 马俊骥

    2008-01-01

    目的 探讨何首乌对衰老大鼠海马BDNF mRNA表达的影响.方法 给大鼠注射大剂量D-半乳糖,通过行为学测试和RT-PCR方法,观测海马BDNF mRNA含量的变化.结果 与对照组比较,D-半乳糖组大鼠海马BDNF mRNA含量降低,何首乌组海马BDNF mRNA含量亦降低.结论 何首乌不影响BDNF mRNA的表达量.

  20. Determinants genòmics de la condició física: influència del polimorfisme BDNF val66met en la recuperació cardíaca postesforç

    OpenAIRE

    Sánchez Malagón, Josep

    2012-01-01

    Introduction: A commmon single nucleotide polymorphism in the human brain derived neurotrophic factor (BDNF) gene (Val66met) may have a modulatory effect on the cardiac sympathovagal balance (Yang A. , Chen, Tsai, Hong, Kuo, & Yang, 2010). Recovery of the heart rate immediately after exercise is a function of vagal reactivation. During exercise the increase of the simpathetic activity and the decrease of the vagal activity produce an increase of the cardiac heart rate. The parasimpathetic act...

  1. Low serum BDNF levels in depressed patients cannot be attributed to individual depressive symptoms or symptom cluster

    NARCIS (Netherlands)

    Bus, B.A.; Molendijk, M.L.; Penninx, B.W.; Buitelaar, J.; Prickaerts, J.; Elzinga, B.M.; Oude Voshaar, R.C.

    2014-01-01

    Abstract Objectives. Low serum BDNF levels have been found in depressed patients. No study has systematically investigated whether individual symptoms or symptom profiles within a depressed population contribute to low BDNF levels found in depressed subjects. Methods. All 1070 patients with a past 6

  2. Chronic Fluoxetine Treatment Induces Brain Region-Specific Upregulation of Genes Associated with BDNF-Induced Long-Term Potentiation

    Directory of Open Access Journals (Sweden)

    Maria Nordheim Alme

    2007-01-01

    Full Text Available Several lines of evidence implicate BDNF in the pathogenesis of stress-induced depression and the delayed efficacy of antidepressant drugs. Antidepressant-induced upregulation of BDNF signaling is thought to promote adaptive neuronal plasticity through effects on gene expression, but the effector genes downstream of BDNF has not been identified. Local infusion of BDNF into the dentate gyrus induces a long-term potentiation (BDNF-LTP of synaptic transmission that requires upregulation of the immediate early gene Arc. Recently, we identified five genes (neuritin, Narp, TIEG1, Carp, and Arl4d that are coupregulated with Arc during BDNF-LTP. Here, we examined the expression of these genes in the dentate gyrus, hippocampus proper, and prefrontal cortex after antidepressant treatment. We show that chronic, but not acute, fluoxetine administration leads to upregulation of these BDNF-LTP-associated genes in a brain region-specific pattern. These findings link chronic effects of antidepressant treatment to molecular mechanisms underlying BDNF-induced synaptic plasticity.

  3. Chronic fluoxetine treatment induces brain region-specific upregulation of genes associated with BDNF-induced long-term potentiation.

    Science.gov (United States)

    Alme, Maria Nordheim; Wibrand, Karin; Dagestad, Grethe; Bramham, Clive R

    2007-01-01

    Several lines of evidence implicate BDNF in the pathogenesis of stress-induced depression and the delayed efficacy of antidepressant drugs. Antidepressant-induced upregulation of BDNF signaling is thought to promote adaptive neuronal plasticity through effects on gene expression, but the effector genes downstream of BDNF has not been identified. Local infusion of BDNF into the dentate gyrus induces a long-term potentiation (BDNF-LTP) of synaptic transmission that requires upregulation of the immediate early gene Arc. Recently, we identified five genes (neuritin, Narp, TIEG1, Carp, and Arl4d) that are coupregulated with Arc during BDNF-LTP. Here, we examined the expression of these genes in the dentate gyrus, hippocampus proper, and prefrontal cortex after antidepressant treatment. We show that chronic, but not acute, fluoxetine administration leads to upregulation of these BDNF-LTP-associated genes in a brain region-specific pattern. These findings link chronic effects of antidepressant treatment to molecular mechanisms underlying BDNF-induced synaptic plasticity. PMID:18301726

  4. Low serum BDNF levels in depressed patients cannot be attributed to individual depressive symptoms or symptom cluster

    NARCIS (Netherlands)

    Bus, B. A. A.; Molendijk, M. L.; Penninx, B. W. J. H.; Buitelaar, J. K.; Prickaerts, J.; Elzinga, B. M.; Oude Voshaar, R. C.

    2014-01-01

    OBJECTIVES: Low serum BDNF levels have been found in depressed patients. No study has systematically investigated whether individual symptoms or symptom profiles within a depressed population contribute to low BDNF levels found in depressed subjects. METHODS: All 1070 patients with a past 6-month di

  5. Plasma BDNF Is Reduced among Middle-Aged and Elderly Women with Impaired Insulin Function: Evidence of a Compensatory Mechanism

    Science.gov (United States)

    Arentoft, Alyssa; Sweat, Victoria; Starr, Vanessa; Oliver, Stephen; Hassenstab, Jason; Bruehl, Hannah; Tirsi, Aziz; Javier, Elizabeth; McHugh, Pauline F.; Convit, Antonio

    2009-01-01

    Brain-derived neurotrophic factor (BDNF) plays a regulatory role in neuronal differentiation and synaptic plasticity and has been linked to glucose regulation and cognition. Associations among plasma BDNF, cognition, and insulin function were explored. Forty-one participants with impaired insulin function (IIF), ranging from insulin resistance to…

  6. Research Progress of BDNF and Depression%BDNF与抑郁症的研究现状及进展

    Institute of Scientific and Technical Information of China (English)

    乔卉; 安书成; 徐畅

    2011-01-01

    BDNF is widespread existed in CNS and PNS, because of its function in nerve regeneration and restoration, more and more researches focused on the effect of BDNF on neural plasticity in the development of depression and the mechanisms of antidepressant. This article review the basic results and the research trends on BDNF and depression at present, more researches about the interactions of BDNF and proBDNF, BDNF and other transmitters and their receptors should be expected.%脑源性神经营养因子(brain-derived neurothrophic factor,BDNF)在中枢和外周均广泛存在,基于对其神经再生和修复功能的普遍认识,越来越多的研究开始关注BDNF在抑郁发生过程中对神经可塑性的影响以及BDNF在抗抑郁药物治疗中发挥的作用.本文综述了BDNF与抑郁症关系的基础性研究成果,以及近两年的相关研究趋势,更多的关于BDNF与其前体(precursor of brain derived neurothrophic factor,proBDNF)以及BDNF与其它神经递质在神经网络中的相互作用的研究需要被深入开展.

  7. The impact of childhood abuse and recent stress on serum brain-derived neurotrophic factor and the moderating role of BDNF Val(66)Met

    NARCIS (Netherlands)

    Elzinga, Bernet M.; Molendijk, Marc L.; Voshaar, Richard C. Oude; Bus, Boudewijn A. A.; Prickaerts, Jos; Spinhoven, Philip; Penninx, Brenda J. W. H.

    2011-01-01

    Recent findings show lowered brain-derived neurotrophic factor (BDNF) levels in major depressive disorder (MDD). Exposure to stressful life events may (partly) underlie these BDNF reductions, but little is known about the effects of early or recent life stress on BDNF levels. Moreover, the effects o

  8. The impact of childhood abuse and recent stress on serum brain-derived neurotrophic factor and the moderating role of BDNF Val66Met

    NARCIS (Netherlands)

    Elzinga, B.M.; Molendijk, M.L.; Oude Voshaar, R.C.; Bus, B.A.A.; Prickaerts, J.; Spinhoven, P.; Penninx, B.J.

    2011-01-01

    RATIONALE: Recent findings show lowered brain-derived neurotrophic factor (BDNF) levels in major depressive disorder (MDD). Exposure to stressful life events may (partly) underlie these BDNF reductions, but little is known about the effects of early or recent life stress on BDNF levels. Moreover, th

  9. Association between DNA Methylation of the BDNF Promoter Region and Clinical Presentation in Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Tomoyuki Nagata

    2015-03-01

    Full Text Available Background/Aims: In the present study, we examined whether DNA methylation of the brain-derived neurotrophic factor (BDNF promoter is associated with the manifestation and clinical presentation of Alzheimer's disease (AD. Methods: Of 20 patients with AD and 20 age-matched normal controls (NCs, the DNA methylation of the BDNF promoter (measured using peripheral blood samples was completely analyzed in 12 patients with AD and 6 NCs. The resulting methylation levels were compared statistically. Next, we investigated the correlation between the DNA methylation levels and the clinical presentation of AD. Results: The total methylation ratio (in % of the 20 CpG sites was significantly higher in the AD patients (5.08 ± 5.52% than in the NCs (2.09 ± 0.81%; p Conclusion: These results suggest that the DNA methylation of the BDNF promoter may significantly influence the manifestation of AD and might be associated with its neurocognitive presentation.

  10. Effects of the BDNF Val66Met polymorphism on white matter microstructure in healthy adults.

    Science.gov (United States)

    Tost, Heike; Alam, Tajvar; Geramita, Matthew; Rebsch, Christine; Kolachana, Bhaskar; Dickinson, Dwight; Verchinski, Beth A; Lemaitre, Herve; Barnett, Alan S; Trampush, Joey W; Weinberger, Daniel R; Marenco, Stefano

    2013-02-01

    The BDNF Val(66)Met polymorphism, a possible risk variant for mental disorders, is a potent modulator of neural plasticity in humans and has been linked to deficits in gray matter structure, function, and cognition. The impact of the variant on brain white matter structure, however, is controversial and remains poorly understood. Here, we used diffusion tensor imaging to examine the effects of BDNF Val(66)Met genotype on white matter microstructure in a sample of 85 healthy Caucasian adults. We demonstrate decreases of fractional anisotropy and widespread increases in radial diffusivity in Val/Val homozygotes compared with Met-allele carriers, particularly in prefrontal and occipital pathways. These data provide an independent confirmation of prior imaging genetics work, are consistent with complex effects of the BDNF Val(66)Met polymorphism on human brain structure, and may serve to generate hypotheses about variation in white matter microstructure in mental disorders associated with this variant. PMID:23132269

  11. Changes in spatial memory and BDNF expression to simultaneous dietary restriction and forced exercise.

    Science.gov (United States)

    Khabour, Omar F; Alzoubi, Karem H; Alomari, Mahmoud A; Alzubi, Mohammad A

    2013-01-01

    Previous literature suggests that learning and memory formation can be influenced by diet and exercise. In the current study, we investigated the combined effects of forced swimming exercise (FSE) and every other day fasting (EODF) on spatial memory formation and on the levels of brain-derived neurotrophic factor (BDNF) in the hippocampus of Wistar male rats. The radial arm water maze (RAWM) paradigm was used to assess changes in learning and memory formation, whereas ELISA assay was used to measure BDNF protein levels. The FSE and/or EODF were simultaneously instituted for 6 weeks. Results show that FSE improved learning, short-term as well as long-term memory formation, and significantly increased BDNF protein in the hippocampus (p0.05). In addition, EODF did not modulate beneficial effect of swimming exercise on cognitive function (p>0.05). Thus exercise enhanced, while EODF did not affect spatial learning and memory formation. PMID:23000024

  12. Increased serum levels of sortilin are associated with depression and correlated with BDNF and VEGF

    DEFF Research Database (Denmark)

    Buttenschøn, Henriette Nørmølle; Demontis, Ditte; Ollendorff, Mathias Kaas;

    2015-01-01

    measured by immunoassay, and potential determinants of the serum sortilin level were assessed by generalized linear models. Serum levels of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) were measured in previous studies. We identified a significant increase of serum...... sortilin levels in depressed individuals compared with controls (P = 0.0002) and significant positive correlation between serum sortilin levels and the corresponding levels of BDNF and VEGF. None of the genotyped SNPs were associated with depression. Additional analyses showed that the serum sortilin level...... was influenced by several other factors. Alcohol intake and body mass index, as well as depression, serum BDNF and serum VEGF were identified as predictors of serum sortilin levels in our final multivariate model. In conclusion, the results suggest a role of circulating sortilin in depression which may relate...

  13. Synthesis, Superoxide Dismutase Mimetic and Anticancer Activities of Metal Complexes of 2,2-Dimethylpentanedioic Acid(2dmepdaH2 and 3,3-Dimethylpentanedioic acid(3dmepdaH2: X-Ray Crystal Structures of [Cu(3dmepda(bipy]2⋅6H2O and [Cu(2dmepda(bipy(EtOH]2⋅4EtOH(bipy=2,2′Bipyridine

    Directory of Open Access Journals (Sweden)

    Carol Deegan

    2005-03-01

    Full Text Available 2,2-dimethylpentanedioic acid (2dmepdaH2 and 3,3-dimethylpentanedioic acid (3dmepdaH2 reacted with copper(II acetate to give [Cu(2dmepda(H2O3]2 (1 and [Cu(3dmepda(H2O3]2 (2. Reaction of (1 and (2 with 1,10-phenanthroline and 2,2′-bipyridine yielded [Cu(2dmepda(phen(H2O]20.5phen (3, [Cu(2dmepda(bipy(H2O]2 (4, [Cu(2dmepda(bipy(EtOH]2⋅2EtOH (4A, [Cu(3dmepda(phen(H2O]2 (5, and [Cu(3dmepda(bipy(H2O]2⋅ (6. The structures of (4A and (6 each consists of a [Cu(bipy(dicarboxylate(solvent]2 dimer. The superoxide dismutase (SOD mimetic activity of the novel copper complexes and their manganese analogues was investigated. The dimethyl sulphoxide(DMSO soluble complexes (1–(4 and (6 were assessed for their cancer chemotherapeutic potential towards hepatocellular carcinoma and kidney adenocarcinoma cell lines. The 1,10-phenanthroline containing complex [Cu(2dmepda(phen(H2O]20.5phen (3 was the most potent with activity that compares well to that of cisplatin.

  14. BDNF Val66met and 5-HTTLPR polymorphisms predict a human in vivo marker for brain serotonin levels

    DEFF Research Database (Denmark)

    Fisher, Patrick M; Holst, Klaus K; Adamsen, Dea;

    2015-01-01

    Brain-derived neurotrophic factor (BDNF) has been implicated in multiple aspects of brain function including regulation of serotonin signaling. The BDNF val66met polymorphism (rs6265) has been linked to aspects of serotonin signaling in humans but its effects are not well understood. To address...... this, we evaluated whether BDNF val66met was predictive of a putative marker of brain serotonin levels, serotonin 4 receptor (5-HT4 ) binding assessed with [(11) C]SB207145 positron emission tomography, which has also been associated with the serotonin-transporter-linked polymorphic region (5-HTTLPR...... BDNF val66met significantly predicted a LV reflecting [(11) C]SB207145 binding across regions (P = 0.005). BDNF val66met met-carriers showed 2-9% higher binding relative to val/val homozygotes. In contrast, 5-HTTLPR did not predict the LV but S-carriers showed 7% lower neocortical binding relative...

  15. Tunable elastin-mimetic multiblock hybrid copolymers for biomedical applications

    Science.gov (United States)

    Grieshaber, Sarah Elizabeth

    Elastin-mimetic hybrid polymers (EMHPs) have been developed to capture the multiblock molecular architecture of tropoelastin, allowing tunability in chemical, structural, biological, and mechanical properties. Multiblock EMHPs containing flexible synthetic segments were first synthesized via step growth polymerization of diazido-poly(ethylene glycol) (PEG) and alkyne-terminated AKA3KA (K = lysine, A = alanine) (AK2) peptide employing copper (I)-catalyzed alkyne-azide cycloaddition reaction (CuAAC, or orthogonal click chemistry). Covalent crosslinking of the EMHPs with hexamethylene diisocyanate (HMDI) through the lysine residues in the peptide domain afforded an elastomeric hydrogel (xEMHP) with a compressive modulus of 0.12 +/- 0.018 MPa when hydrated. xEMHPs exhibited minimal cytotoxicity to primary porcine vocal fold fibroblasts. The modular nature of the synthesis allowed facile adjustment of the peptide sequence to modulate the structural and the biological properties of EMHPs. Thus, EMHPs containing integrin-binding peptides were constructed using di-azido-PEG and an alkyne-terminated AK2 peptide with a terminal, integrin-binding GRGDSP domain via the step growth click coupling reaction. Hydrogels formed by covalent crosslinking of the RGD-containing EMHPs had a compressive modulus of 1.06 +/- 0.1MPa when hydrated. Neonatal human dermal fibroblasts (NHDFs) were able to adhere to the hydrogels within 1 h, and to spread and develop F-actin filaments 24 h post seeding. NHDF proliferation was only observed on hydrogels containing RGD domains, demonstrating the importance of integrin engagement for cell growth and the potential use of these EMHPs as tissue engineering scaffolds. The tunability of the EMHP system was further investigated by development of self-assembling, pH-responsive multiblock polymers composed of alternating domains of poly(acrylic acid) (PAA) and a peptide derived from the hydrophobic domains of elastin with the sequence (VPGVG)2 (VG2). The

  16. Fetal iron deficiency induces chromatin remodeling at the Bdnf locus in adult rat hippocampus.

    Science.gov (United States)

    Tran, Phu V; Kennedy, Bruce C; Lien, Yu-Chin; Simmons, Rebecca A; Georgieff, Michael K

    2015-02-15

    Fetal and subsequent early postnatal iron deficiency causes persistent impairments in cognitive and affective behaviors despite prompt postnatal iron repletion. The long-term cognitive impacts are accompanied by persistent downregulation of brain-derived neurotrophic factor (BDNF), a factor critical for hippocampal plasticity across the life span. This study determined whether early-life iron deficiency epigenetically modifies the Bdnf locus and whether dietary choline supplementation during late gestation reverses these modifications. DNA methylation and histone modifications were assessed at the Bdnf-IV promoter in the hippocampus of rats [at postnatal day (PND) 65] that were iron-deficient (ID) during the fetal-neonatal period. Iron deficiency was induced in rat pups by providing pregnant and nursing dams an ID diet (4 mg/kg Fe) from gestational day (G) 2 through PND7, after which iron deficiency was treated with an iron-sufficient (IS) diet (200 mg/kg Fe). This paradigm resulted in about 60% hippocampal iron loss on PND15 with complete recovery by PND65. For choline supplementation, pregnant rat dams were given dietary choline (5 g/kg) from G11 through G18. DNA methylation was determined by quantitative sequencing of bisulfite-treated DNA, revealing a small alteration at the Bdnf-IV promoter. Chromatin immunoprecipitation analysis showed increased HDAC1 binding accompanied by reduced binding of RNA polymerase II and USF1 at the Bdnf-IV promoter in formerly ID rats. These changes were correlated with altered histone methylations. Prenatal choline supplementation reverses these epigenetic modifications. Collectively, the findings identify epigenetic modifications as a potential mechanism to explicate the long-term repression of Bdnf following fetal and early postnatal iron deficiency.

  17. NRSF and BDNF polymorphisms as biomarkers of cognitive dysfunction in adults with newly diagnosed epilepsy.

    Science.gov (United States)

    Warburton, Alix; Miyajima, Fabio; Shazadi, Kanvel; Crossley, Joanne; Johnson, Michael R; Marson, Anthony G; Baker, Gus A; Quinn, John P; Sills, Graeme J

    2016-01-01

    Cognitive dysfunction is a common comorbidity in people with epilepsy, but its causes remain unclear. It may be related to the etiology of the disorder, the consequences of seizures, or the effects of antiepileptic drug treatment. Genetics may also play a contributory role. We investigated the influence of variants in the genes encoding neuron-restrictive silencer factor (NRSF) and brain-derived neurotrophic factor (BDNF), proteins previously associated with cognition and epilepsy, on cognitive function in people with newly diagnosed epilepsy. A total of 82 patients who had previously undergone detailed neuropsychological assessment were genotyped for single nucleotide polymorphisms (SNPs) across the NRSF and BDNF genes. Putatively functional SNPs were included in a genetic association analysis with specific cognitive domains, including memory, psychomotor speed, and information processing. Cross-sectional and longitudinal designs were used to explore genetic influences on baseline cognition at diagnosis and change from baseline over the first year since diagnosis, respectively. We found a statistically significant association between genotypic variation and memory function at both baseline (NRSF: rs1105434, rs2227902 and BDNF: rs1491850, rs2030324, rs11030094) and in our longitudinal analysis (NRSF: rs2227902 and BDNF: rs12273363). Psychomotor speed was also associated with genotype (NRSF rs3796529) in the longitudinal assessment. In line with our previous work on general cognitive function in the healthy aging population, we observed an additive interaction between risk alleles for the NRSF rs2227902 (G) and BDNF rs6265 (A) polymorphisms which was again consistent with a significantly greater decline in delayed recall over the first year since diagnosis. These findings support a role for the NRSF-BDNF pathway in the modulation of cognitive function in patients with newly diagnosed epilepsy.

  18. Late Protein Synthesis-Dependent Phases in CTA Long-Term Memory: BDNF Requirement

    Science.gov (United States)

    Martínez-Moreno, Araceli; Rodríguez-Durán, Luis F.; Escobar, Martha L.

    2011-01-01

    It has been proposed that long-term memory (LTM) persistence requires a late protein synthesis-dependent phase, even many hours after memory acquisition. Brain-derived neurotrophic factor (BDNF) is an essential protein synthesis product that has emerged as one of the most potent molecular mediators for long-term synaptic plasticity. Studies in the rat hippocampus have been shown that BDNF is capable to rescue the late-phase of long-term potentiation as well as the hippocampus-related LTM when protein synthesis was inhibited. Our previous studies on the insular cortex (IC), a region of the temporal cortex implicated in the acquisition and storage of conditioned taste aversion (CTA), have demonstrated that intracortical delivery of BDNF reverses the deficit in CTA memory caused by the inhibition of IC protein synthesis due to anisomycin administration during early acquisition. In this work, we first analyze whether CTA memory storage is protein synthesis-dependent in different time windows. We observed that CTA memory become sensible to protein synthesis inhibition 5 and 7 h after acquisition. Then, we explore the effect of BDNF delivery (2 μg/2 μl per side) in the IC during those late protein synthesis-dependent phases. Our results show that BDNF reverses the CTA memory deficit produced by protein synthesis inhibition in both phases. These findings support the notion that recurrent rounds of consolidation-like events take place in the neocortex for maintenance of CTA memory trace and that BDNF is an essential component of these processes. PMID:21960964

  19. Brain-derived neurotrophic factor (BDNF as a potential mechanism of the effects of acute exercise on cognitive performance

    Directory of Open Access Journals (Sweden)

    Aaron T. Piepmeier

    2015-03-01

    Full Text Available The literature shows that improvements in cognitive performance may be observed following an acute bout of exercise. However, evidence in support of the biological mechanisms of this effect is still limited. Findings from both rodent and human studies suggest brain-derived neurotrophic factor (BDNF as a potential mechanism of the effect of acute exercise on memory. The molecular properties of BDNF allow this protein to be assessed in the periphery (pBDNF (i.e., blood serum, blood plasma, making measurements of acute exercise-induced changes in BDNF concentration relatively accessible. Studies exploring the acute exercise–pBDNF–cognitive performance relationship have had mixed findings, but this may be more reflective of methodological differences between studies than it is a statement about the role of BDNF. For example, significant associations have been observed between acute exercise-induced changes in pBDNF concentration and cognitive performance in studies assessing memory, and non-significant associations have been found in studies assessing non-memory cognitive domains. Three suggestions are made for future research aimed at understanding the role of BDNF as a biological mechanism of this relationship: 1 Assessments of cognitive performance may benefit from a focus on various types of memory (e.g., relational, spatial, long-term; 2 More fine-grained measurements of pBDNF will allow for the assessment of concentrations of specific isoforms of the BDNF protein (i.e., immature, mature; 3 Statistical techniques designed to test the mediating role of pBDNF in the acute exercise-cognitive performance relationship should be utilized in order to make causal inferences.

  20. Distinct effect of CacyBP/SIP on the ERK1/2-CREB-BDNF pathway in undifferentiated and differentiated neuroblastoma NB2a cells.

    Science.gov (United States)

    Rosińska, Sara; Leśniak, Wiesława; Filipek, Anna

    2016-07-01

    CacyBP/SIP, a protein expressed to high extent in the brain, has been shown to act as ERK1/2 phosphatase in vitro and in cultured cells. It has been demonstrated recently that CacyBP/SIP can modulate the activity of some transcription factors in neurons and glioma cells. In the present work we have examined the effect of CacyBP/SIP overexpression and silencing on the phosphorylation/activity of ERK1/2 (pERK1/2) and CREB (pCREB) and on the level of BDNF mRNA in differentiated and undifferentiated neuroblastoma NB2a cells. We have shown that in undifferentiated cells the amount of pERK1/2 decreased upon CacyBP/SIP overexpression. Further studies have shown that the activity of CREB and the level of BDNF mRNA, downstream effectors of the ERK1/2 signaling pathway, also depended on the CacyBP/SIP level and strictly matched the level of pERK1/2. Interestingly, in differentiated NB2a cells, overexpression of CacyBP/SIP appeared to have a distinct effect on the pERK1/2 level from that observed in undifferentiated cells. Subsequent studies have revealed that distinct function of CacyBP/SIP in undifferentiated and differentiated NB2a cells might be due to changes in its posttranslational modifications and protein ligands. Altogether, our studies suggest that CacyBP/SIP is involved in the ERK1/2-CREB-BDNF pathway and that it might regulate this pathway depending on the stage of NB2a cell differentiation. PMID:27180052

  1. DIFFERENT CIRCULATING BRAIN-DERIVED NEUROTROPHIC FACTOR RESPONSES TO ACUTE EXERCISE BETWEEN PHYSICALLY ACTIVE AND SEDENTARY SUBJECTS

    Directory of Open Access Journals (Sweden)

    Yu Nofuji

    2012-03-01

    Full Text Available Although circulating brain-derived neurotrophic factor (BDNF level is affected by both acute and chronic physical activity, the interaction of acute and chronic physical activity was still unclear. In this study, we compared the serum and plasma BDNF responses to maximal and submaximal acute exercises between physically active and sedentary subjects. Eight active and 8 sedentary female subjects participated in the present study. Both groups performed 3 exercise tests with different intensities, i.e. 100% (maximal, 60% (moderate and 40% (low of their peak oxygen uptake. In each exercise test, blood samples were taken at the baseline and immediately, 30 and 60 min after the test. The serum BDNF concentration was found to significantly increase immediately after maximal and moderate exercise tests in both groups. In maximal exercise test, the pattern of change in the serum BDNF concentration was different between the groups. While the serum BDNF level for the sedentary group returned to the baseline level during the recovery phase, the BDNF levels for the active group decreased below the baseline level after the maximal exercise test. No group differences were observed in the pattern of plasma BDNF change for all exercise tests. These findings suggest that regular exercise facilitates the utilization of circulating BDNF during and/or after acute exercise with maximal intensity

  2. Molecular mechanisms underlying the regulation of brain-derived neurotrophic factor (BDNF) translation in dendrites

    OpenAIRE

    Pinheiro, Vera Lúcia Margarido

    2010-01-01

    A especificidade espacial e temporal subjacente à diversidade de processos de plasticidade sináptica que ocorrem no sistema nervoso central está profundamente relacionada com a disponibilidade da proteína brain-derived neurotrophic factor (BDNF) em domínios sub-celulares distintos, especialmente na área pós-sináptica. Contudo, os mecanismos moleculares que regulam a síntese proteica de BDNF nas dendrites estão ainda por desvendar. Assim, o principal objectivo deste trabalho foi...

  3. Juvenile methylphenidate reduces prefrontal cortex plasticity via D3 receptor and BDNF in adulthood

    Directory of Open Access Journals (Sweden)

    Susan L Andersen

    2014-01-01

    Full Text Available Background: Early drug intervention in childhood disorders aims to maximize individual potential in the short- and long-term. Consistently, juvenile exposure to psychostimulants, such as methylphenidate (MPH, reduces risk for substance use in animals and sub-populations of individuals with attention deficit hyperactivity disorder (ADHD. We investigated the effects of MPH on brain plasticity via dopamine receptor D3 (D3R and brain-derived neurotrophic factor (BDNF expression in developing rats. Methods: Between postnatal days 20-35, rat pups were administered saline vehicle (Veh or MPH (2 mg/kg, the D3R-preferring agonist ± 7-OHDPAT, or the antagonist nafadotride (0.05 mg/kg alone, or in combination with MPH twice a day. In adulthood, subjects were challenged to Veh or cocaine (10 mg/kg for two days. The prefrontal cortex was analyzed for protein and mRNA levels of total BDNF, its splice variants I, IIc, III/IV, and IV/VI, and D3 receptors. A separate group of subjects was assessed for splice variants at 20, 35, 40 and 60 days. Results: Across age strong correlations were evident between Drd3 and Bdnf mRNA levels (r=0.65 and a negative relationship between Drd3 and exon IIc after MPH exposure (r=-0.73. BDNF protein levels did not differ between Veh- and MPH subjects at baseline, but were significantly lower in MPH-treated and cocaine challenged subjects (30.3 ± 9.7%. Bdnf mRNA was significantly higher in MPH subjects, and reversed upon exposure to cocaine. This effect was blocked by nafadotride. Furthermore, Bdnftotal and Bdnf splice variants I, IIc, III/IV, and IV/VI changed across the transitions between juvenility and late adolescence. Conclusions: These data suggest a sensitive window of vulnerability to modulations of BDNF expression around adolescence, and that compared to normal animals, juvenile exposure to MPH permanently reduces prefrontal BDNF transcription and translation upon cocaine exposure in adulthood by a D3R

  4. Light-switched inhibitors of protein tyrosine phosphatase PTP1B based on phosphonocarbonyl phenylalanine as photoactive phosphotyrosine mimetic.

    Science.gov (United States)

    Wagner, Stefan; Schütz, Anja; Rademann, Jörg

    2015-06-15

    Phosphopeptide mimetics containing the 4-phosphonocarbonyl phenylalanine (pcF) as a photo-active phosphotyrosine isoster are developed as potent, light-switchable inhibitors of the protein tyrosine phosphatase PTP1B. The photo-active inhibitors 6-10 are derived from phosphopeptide substrates and are prepared from the suitably protected pcF building block 12 by Fmoc-based solid phase peptide synthesis. All pcF-containing peptides are moderate inhibitors of PTP1B with KI values between 10 and 50μM. Irradiation of the inhibitors at 365nm in the presence of the protein PTP1B amplify the inhibitory activity of pcF-peptides up to 120-fold, switching the KI values of the best inhibitors to the sub-micromolar range. Photo-activation of the inhibitors results in the formation of triplet intermediates of the benzoylphosphonate moiety, which deactivate PTP1B following an oxidative radical mechanism. Deactivation of PTP1B proceeds without covalent crosslinking of the protein target with the photo-switched inhibitors and can be reverted by subsequent addition of reducing agent dithiothreitol (DTT).

  5. A small molecule glycosaminoglycan mimetic blocks Plasmodium invasion of the mosquito midgut.

    Directory of Open Access Journals (Sweden)

    Derrick K Mathias

    Full Text Available Malaria transmission-blocking (T-B interventions are essential for malaria elimination. Small molecules that inhibit the Plasmodium ookinete-to-oocyst transition in the midgut of Anopheles mosquitoes, thereby blocking sporogony, represent one approach to achieving this goal. Chondroitin sulfate glycosaminoglycans (CS-GAGs on the Anopheles gambiae midgut surface are putative ligands for Plasmodium falciparum ookinetes. We hypothesized that our synthetic polysulfonated polymer, VS1, acting as a decoy molecular mimetic of midgut CS-GAGs confers malaria T-B activity. In our study, VS1 repeatedly reduced midgut oocyst development by as much as 99% (P<0.0001 in mosquitoes fed with P. falciparum and Plasmodium berghei. Through direct-binding assays, we observed that VS1 bound to two critical ookinete micronemal proteins, each containing at least one von Willebrand factor A (vWA domain: (i circumsporozoite protein and thrombospondin-related anonymous protein-related protein (CTRP and (ii vWA domain-related protein (WARP. By immunofluorescence microscopy, we observed that VS1 stains permeabilized P. falciparum and P. berghei ookinetes but does not stain P. berghei CTRP knockouts or transgenic parasites lacking the vWA domains of CTRP while retaining the thrombospondin repeat region. We produced structural homology models of the first vWA domain of CTRP and identified, as expected, putative GAG-binding sites on CTRP that align closely with those predicted for the human vWA A1 domain and the Toxoplasma gondii MIC2 adhesin. Importantly, the models also identified patches of electropositive residues that may extend CTRP's GAG-binding motif and thus potentiate VS1 binding. Our molecule binds to a critical, conserved ookinete protein, CTRP, and exhibits potent malaria T-B activity. This study lays the framework for a high-throughput screen of existing libraries of safe compounds to identify those with potent T-B activity. We envision that such compounds when

  6. Brain Derived Neurotrophic Factor (BDNF) levels as a possible predictor of psychopathology in healthy twins at high and low risk for affective disorder

    DEFF Research Database (Denmark)

    Vinberg, Maj; Miskowiak, Kamilla; Kessing, Lars Vedel

    2014-01-01

    Brain Derived Neurotrophic Factor (BDNF) is a potential biomarker of affective disorder. However, longitudinal studies evaluating a potential predictive role of BDNF on subsequent psychopathology are lacking. The aim of this study was to investigate whether BDNF alone or in interaction...... with the BDNF Val66Met polymorphism predict onset of affective disorder in healthy individuals at heritable risk for affective disorder. In a high-risk study, we assessed whole blood levels of BDNF in 234 healthy monozygotic and dizygotic twins with or without a co-twin history of affective disorder (high...... developed psychiatric disorder. Cox regression analysis revealed that BDNF levels at baseline were not associated with onset of illness in this explorative study. Further, two-way interactions between BDNF levels and the Val66Met polymorphism or between familial risk and the Val66Met polymorphism did...

  7. Furoxans (1,2,5-Oxadiazole-N-Oxides) as Novel NO Mimetic Neuroprotective and Procognitive Agents

    Energy Technology Data Exchange (ETDEWEB)

    Schiefer, Isaac T.; VandeVrede, Lawren; Fa; , Mauro; Arancio, Ottavio; Thatcher, Gregory R.J. (Columbia); (UIC)

    2012-08-31

    Furoxans (1,2,5-oxadiazole-N-oxides) are thiol-bioactivated NO-mimetics that have not hitherto been studied in the CNS. Incorporation of varied substituents adjacent to the furoxan ring system led to modulation of reactivity toward bioactivation, studied by HPLC-MS/MS analysis of reaction products. Attenuated reactivity unmasked the cytoprotective actions of NO in contrast to the cytotoxic actions of higher NO fluxes reported previously for furoxans. Neuroprotection was observed in primary neuronal cell cultures following oxygen glucose deprivation (OGD). Neuroprotective activity was observed to correlate with thiol-dependent bioactivation to produce NO{sub 2}{sup -}, but not with depletion of free thiol itself. Neuroprotection was abrogated upon cotreatment with a sGC inhibitor, ODQ, thus supporting activation of the NO/sGC/CREB signaling cascade by furoxans. Long-term potentiation (LTP), essential for learning and memory, has been shown to be potentiated by NO signaling, therefore, a peptidomimetic furoxan was tested in hippocampal slices treated with oligomeric amyloid-{beta} peptide (A{beta}) and was shown to restore synaptic function. The novel observation of furoxan activity of potential therapeutic use in the CNS warrants further studies.

  8. Methylidynetrisphosphonates: Promising C1 building block for the design of phosphate mimetics

    Directory of Open Access Journals (Sweden)

    Vadim D. Romanenko

    2013-05-01

    Full Text Available Methylidynetrisphosphonates are representatives of geminal polyphosphonates bearing three phosphonate (PO3H2 groups at the bridged carbon atom. Like well-known methylenebisphosphonates (BPs, they are characterized by a P–C–P backbone structure and are chemically stable mimetics of the endogenous metabolites, i.e., inorganic pyrophosphates (PPi. Because of its analogy to PPi and an ability to chelate metal ions, the 1,1,1-trisphosphonate structure is of great potential as a C1 building block for the design of phosphate mimetics. The purpose of this review is to present a concise summary of the state of the art in trisphosphonate chemistry with particular emphasis on the synthesis, structure, reactions, and potential medicinal applications of these compounds.

  9. Mimetic Theory for Cell-Centered Lagrangian Finite Volume Formulation on General Unstructured Grids

    Energy Technology Data Exchange (ETDEWEB)

    Sambasivan, Shiv Kumar [Los Alamos National Laboratory; Shashkov, Mikhail J. [Los Alamos National Laboratory; Burton, Donald E. [Los Alamos National Laboratory; Christon, Mark A. [Los Alamos National Laboratory

    2012-07-19

    A finite volume cell-centered Lagrangian scheme for solving large deformation problems is constructed based on the hypo-elastic model and using the mimetic theory. Rigorous analysis in the context of gas and solid dynamics, and arbitrary polygonal meshes, is presented to demonstrate the ability of cell-centered schemes in mimicking the continuum properties and principles at the discrete level. A new mimetic formulation based gradient evaluation technique and physics-based, frame independent and symmetry preserving slope limiters are proposed. Furthermore, a physically consistent dissipation model is employed which is both robust and inexpensive to implement. The cell-centered scheme along with these additional new features are applied to solve solids undergoing elasto-plastic deformation.

  10. A new tool in peptide engineering: a photoswitchable stilbene-type beta-hairpin mimetic.

    Science.gov (United States)

    Erdélyi, Máté; Karlén, Anders; Gogoll, Adolf

    2005-12-23

    Peptide secondary structure mimetics are important tools in medicinal chemistry, as they provide analogues of endogenous peptides with new physicochemical and pharmacological properties. The development, synthesis, photochemical investigation, and conformational analysis of a stilbene-type beta-hairpin mimetic capable of light-triggered conformational changes have been achieved. In addition to standard spectroscopic techniques (nuclear Overhauser effects, amide temperature coefficients, circular dichroism spectroscopy), the applicability of self-diffusion measurements (longitudinal eddy current delay pulsed-field gradient spin echo (LED-PGSE) NMR technique) in conformational studies of oligopeptides is demonstrated. The title compound shows photoisomerization of the stilbene chromophore, resulting in a change in solution conformation between an unfolded structure and a folded beta-hairpin.

  11. Viable Mimetic Completion of Unified Inflation-Dark Energy Evolution in Modified Gravity

    CERN Document Server

    Nojiri, S; Oikonomou, V K

    2016-01-01

    In this paper, we demonstrate that a unified description of early and late-time acceleration is possible in the context of mimetic $F(R)$ gravity. We study the inflationary era in detail and demonstrate that it can be realized even in mimetic $F(R)$ gravity where traditional $F(R)$ gravity fails to describe the inflation. By using standard methods we calculated the spectral index of primordial curvature perturbations and the scalar-to-tensor ratio. We use two $F(R)$ gravity models and as it turns out, for both the models under study the observational indices are compatible with both the latest Planck and the BICEP2/Keck array data. Finally, the graceful exit from inflation is guaranteed by the existence of growing curvature perturbations when the slow-roll era ends.

  12. BDNF and Huntingtin protein modifications by manganese: implications for striatal medium spiny neuron pathology in manganese neurotoxicity.

    Science.gov (United States)

    Stansfield, Kirstie H; Bichell, Terry Jo; Bowman, Aaron B; Guilarte, Tomás R

    2014-12-01

    High levels of manganese (Mn) exposure decrease striatal medium spiny neuron (MSN) dendritic length and spine density, but the mechanism(s) are not known. The Huntingtin (HTT) gene has been functionally linked to cortical brain-derived neurotrophic factor (BDNF) support of striatal MSNs via phosphorylation at serine 421. In Huntington's disease, pathogenic CAG repeat expansions of HTT decrease synthesis and disrupt transport of cortical-striatal BDNF, which may contribute to disease, and Mn is a putative environmental modifier of Huntington's disease pathology. Thus, we tested the hypothesis that changes in MSN dendritic morphology Mn due to exposure are associated with decreased BDNF levels and alterations in Htt protein. We report that BDNF levels are decreased in the striatum of Mn-exposed non-human primates and in the cerebral cortex and striatum of mice exposed to Mn. Furthermore, proBDNF and mature BDNF concentrations in primary cortical and hippocampal neuron cultures were decreased by exposure to Mn confirming the in vivo findings. Mn exposure decreased serine 421 phosphorylation of Htt in cortical and hippocampal neurons and increased total Htt levels. These data strongly support the hypothesis that Mn-exposure-related MSN pathology is associated with decreased BDNF trophic support via alterations in Htt. PMID:25099302

  13. The role of brain-derived neurotrophic factor (BDNF in comorbid depression: possible linkage with steroid hormones, cytokines, and nutrition

    Directory of Open Access Journals (Sweden)

    Tadahiro eNumakawa

    2014-09-01

    Full Text Available Increasing evidence demonstrates a connection between growth factor function (including brain-derived neurotrophic factor, BDNF, glucocorticoid levels (one of the steroid hormones, and the pathophysiology of depressive disorders. Because both BDNF and glucocorticoids regulate synaptic function in the central nervous system, their functional interaction is of major concern. Interestingly, alterations in levels of estrogen, another steroid hormone, may play a role in depressive-like behavior in postpartum females with fluctuations of BDNF-related molecules in the brain. BDNF and cytokines, which are protein regulators of inflammation, stimulate multiple intracellular signaling cascades involved in neuropsychiatric illness. Pro-inflammatory cytokines may increase vulnerability to depressive symptoms, such as the increased risk observed in patients with cancer and/or autoimmune diseases. In this review, we discuss the possible relationship between inflammation and depression, in addition to the crosstalk among cytokines, BDNF and steroids. Further, since nutritional status has been shown to affect critical pathways involved in depression through both BDNF function and the monoamine system, we also review current evidence surrounding diet and supplementation (e.g., flavonoids on BDNF-mediated brain functions.

  14. The release of glutamate from cortical neurons regulated by BDNF via the TrkB/Src/PLC-γ1 pathway.

    Science.gov (United States)

    Zhang, Zitao; Fan, Jin; Ren, Yongxin; Zhou, Wei; Yin, Guoyong

    2013-01-01

    The brain-derived neurotrophic factor (BDNF) participates in the regulation of cortical neurons by influencing the release of glutamate. However, the specific mechanisms are unclear. Hence, we isolated and cultured the cortical neurons of Sprague Dawley rats. Specific inhibitors of TrkB, Src, PLC-γ1, Akt, and MEK1/2 (i.e., K252a, PP2, U73122, LY294002, and PD98059, respectively) were used to treat cortical neurons and to detect the glutamate release from cortical neurons stimulated with BDNF. BDNF significantly increased glutamate release, and simultaneously enhanced phosphorylation levels of TrkB, Src, PLC-γ, Akt, and Erk1/2. For BDNF-stimulated cortical neurons, K252a inhibited glutamate release and inhibited the phosphorylation levels of TrkB, Src, PLC-γ, Erk1/2, and Akt (P PLC-γ1 (P 0.05). U73122 inhibited the glutamate release from BDNF-stimulated cortical neurons, but had no influence on the phosphorylation levels of TrkB, Src, Erk1/2, or Akt (P > 0.05). LY294002 and PD98059 did not affect the BDNF-stimulated glutamate release and did not inhibit the phosphorylation levels of TrkB, Src, or PLC-γ1. In summary, BDNF stimulated the glutamate release from cortical neurons via the TrkB/Src/PLC-γ1 signaling pathway.

  15. Expression and purification of BDNF-TAT fusion protein in E.coli and its distribution in brain%BDNF-TAT融合蛋白在大肠杆菌中的表达纯化及脑中分布

    Institute of Scientific and Technical Information of China (English)

    罗道飞; 李文适; 陈姗; 季爱民

    2011-01-01

    目的 在大肠杆菌中表达并纯化BDNF-TAT融合蛋白,研究其靶向性及在脑中的分布.方法 重组质粒PET-30(a)-BDNF-TAT转染至大肠杆菌BL21(DE3)pLysS中,IPTG诱导其表达后用SP-Sepharose阳离子交换柱纯化,纯化后蛋白用0.4 mol/L精氨酸倍比稀释法复性.KM种小鼠采用随机数字表法分为给药组[尾静脉注射复性后BDNF-TAT融合蛋白4 μg(适量生理盐水溶解)]、阴性对照组(尾静脉注射等体积生理盐水)和空白对照组(不进行任何处理),每组各3只.3 h后提取小鼠脑组织全蛋白,Western blotting检测脑组织中BDNF-TAT表达,SABC免疫组化染色观察BDNF-TAT在脑组织中的分布.结果 获得纯度约90%活性的BDNF-TAT融合蛋白.给药组BDNF-TAT蛋白的相对表达最为1.897±0.286,阴性对照组BDNF-TAT蛋白的相对表达量为0.615±0.234,空白对照组BDNF-TAT蛋白的相对表达量为0.335±0.154,比较差异有统计学意义(F=39.019,P=0.0000).免疫组化染色结果显示给药组BDNF-TAT主要分布于小鼠脑组织海马CA1、CA3和DG区,而阴性对照组和空白对照组巾没有明显阳性染色.结论 BDNF-TAT融合蛋白在大肠杆菌中以包涵体形式大量表达,并能通过外周给药靶向至小鼠脑组织.%Objective To explore the expression and purification of BDNF-TAT fusion protein in E.coli, and study its brain-targeting and distribution in brain. Methods Plasmid PET-30(a) -BDNF-TAT was transfected into the E.coli BL21 (DE3)pLysS;the expression of PET-30(a)-BDNF-TAT was induced by isopropyl-beta-d-thiogalactopyranoside (IPTG);this BDNF-TAT fusion protein was purified by SP-Sepharose cation exchange column and then renatured by 0.4 mol/L arginine. According to the random number table method, KM mice were divided into 3 groups: BDNF-TAT treatment group (giving 4 μg BDNF-TAT through intravenous injection, n=3), negative control group (giving same volume of saline through intravenous injection, n=3) and blank control group

  16. Gastric Bypass Surgery Reverses Diabetic Phenotypes in Bdnf-Deficient Mice.

    Science.gov (United States)

    Jiang, Shujun; Wang, Qinghua; Huang, Zan; Song, Anying; Peng, Yu; Hou, Siyuan; Guo, Shiying; Zhu, Weiyun; Yan, Sheng; Lin, Zhaoyu; Gao, Xiang

    2016-08-01

    Duodenum-jejunum gastric bypass (DJB) has been used to treat morbid diabetic patients. However, neither the suitability among patients nor the mechanisms of this surgical treatment is clear. Previously, we reported a new mouse strain named Timo as type 2 diabetes model caused by brain-derived neurotrophic factor (Bdnf) deficiency. In this study, we found that DJB on Timo mice reversed their metabolic abnormalities without altering the expression of Bdnf. Glucose tolerance and insulin sensitivity were improved greatly, along with reduction of fat accumulation in liver and white adipose tissue. The gut flora population was altered by DJB with increased proportion of Firmicutes and decreased Actinobacteria and Proteobacteria in the ileum after surgery. Systemic inflammation in Timo mice was greatly suppressed with less macrophage infiltration and lower tumor necrosis factor-α levels in liver and white adipose tissue after surgery. Interestingly, the alteration of gut microflora abundance and improved metabolism preceded the inflammation alleviation after DJB surgery. These results suggested that DJB can reverse Bdnf deficiency-associated metabolic abnormality. In addition, the reduced inflammation may not be the initial cause for the DJB-associated metabolic and microbiota alterations. The increased BDNF protein levels in hypothalamus and hippocampus may result from microbiota change after DJB surgery. PMID:27418549

  17. Altered social cognition in male BDNF heterozygous mice and following chronic methamphetamine exposure.

    Science.gov (United States)

    Manning, Elizabeth E; van den Buuse, Maarten

    2016-05-15

    Growing clinical evidence suggests that persistent psychosis which occurs in methamphetamine users is closely related to schizophrenia. However, preclinical studies in animal models have focussed on psychosis-related behaviours following methamphetamine, and less work has been done to assess endophenotypes relevant to other deficits observed in schizophrenia. Altered social behaviour is a feature of both the negative symptoms and cognitive deficits in schizophrenia, and significantly impacts patient functioning. We recently found that brain-derived neurotrophic factor (BDNF) heterozygous mice show disrupted sensitization to methamphetamine, supporting other work suggesting an important role of this neurotrophin in the pathophysiology of psychosis and the neuronal response to stimulant drugs. In the current study, we assessed social and cognitive behaviours in methamphetamine-treated BDNF heterozygous mice and wildtype littermate controls. Following chronic methamphetamine exposure male wildtype mice showed a 50% reduction in social novelty preference. Vehicle-treated male BDNF heterozygous mice showed a similar impairment in social novelty preference, with a trend for no further disruption by methamphetamine exposure. Female mice were unaffected in this task, and no groups showed any changes in sociability or short-term spatial memory. These findings suggest that chronic methamphetamine alters behaviour relevant to disruption of social cognition in schizophrenia, supporting other studies which demonstrate a close resemblance between persistent methamphetamine psychosis and schizophrenia. Together these findings suggest that dynamic regulation of BDNF signalling is necessary to mediate the effects of methamphetamine on behaviours relevant to schizophrenia.

  18. Altered social cognition in male BDNF heterozygous mice and following chronic methamphetamine exposure.

    Science.gov (United States)

    Manning, Elizabeth E; van den Buuse, Maarten

    2016-05-15

    Growing clinical evidence suggests that persistent psychosis which occurs in methamphetamine users is closely related to schizophrenia. However, preclinical studies in animal models have focussed on psychosis-related behaviours following methamphetamine, and less work has been done to assess endophenotypes relevant to other deficits observed in schizophrenia. Altered social behaviour is a feature of both the negative symptoms and cognitive deficits in schizophrenia, and significantly impacts patient functioning. We recently found that brain-derived neurotrophic factor (BDNF) heterozygous mice show disrupted sensitization to methamphetamine, supporting other work suggesting an important role of this neurotrophin in the pathophysiology of psychosis and the neuronal response to stimulant drugs. In the current study, we assessed social and cognitive behaviours in methamphetamine-treated BDNF heterozygous mice and wildtype littermate controls. Following chronic methamphetamine exposure male wildtype mice showed a 50% reduction in social novelty preference. Vehicle-treated male BDNF heterozygous mice showed a similar impairment in social novelty preference, with a trend for no further disruption by methamphetamine exposure. Female mice were unaffected in this task, and no groups showed any changes in sociability or short-term spatial memory. These findings suggest that chronic methamphetamine alters behaviour relevant to disruption of social cognition in schizophrenia, supporting other studies which demonstrate a close resemblance between persistent methamphetamine psychosis and schizophrenia. Together these findings suggest that dynamic regulation of BDNF signalling is necessary to mediate the effects of methamphetamine on behaviours relevant to schizophrenia. PMID:26965573

  19. Antihypoxic and Neuroprotective Properties of BDNF and GDNF in vitro and in vivo Under Hypoxic Conditions

    Directory of Open Access Journals (Sweden)

    Vedunova М.V.

    2014-12-01

    Full Text Available The aim of the investigation was to assess antihypoxic and neuroprotective properties of the brain-derived neurotrophic factor (BDNF and the glial cell line-derived neurotrophic factor (GDNF during in vitro and in vivo hypoxia models. Materials and Methods. In vitro studies were performed using hippocampal cells dissociated from 18-days embryonic CBA mice and cultured on multielectrode arrays (MEA60. Hypoxia modeling was performed on day 14 of culture development in vitro by replacing the normoxic culture medium with a medium containing low oxygen for 10 min. In vivo experiments were carried out on C57BL/6j male mice weighing 18–20 g. For acute hypobaric hypoxia a vacuum flow-through chamber was used at the ambient temperature of 20–22°C. We studied the resistance of animals to hypoxia, as well as their spatial memory retention in the Morris water maze upon expiration of 24 h following hypoxia model. Results. The carried out in vitro and in vivo experiments revealed that BDNF and GDNF have strong antihypoxic and neuroprotective effects. Preventive application of BDNF plus GDNF before testing in the Morris water maze, contributed less animal resistance and retention of spatial memory as well as the viability of cells in dissociated hippocampal cultures was decreased in comparison with the isolated effect each of these factors. Conclusion. Application of BDNF in combination with GDNF under hypoxic conditions reduces the positive individual effect these neurotrophic factors.

  20. Action control is mediated by prefrontal BDNF and glucocorticoid receptor binding.

    Science.gov (United States)

    Gourley, Shannon L; Swanson, Andrew M; Jacobs, Andrea M; Howell, Jessica L; Mo, Michelle; Dileone, Ralph J; Koleske, Anthony J; Taylor, Jane R

    2012-12-11

    Stressor exposure biases decision-making strategies from those based on the relationship between actions and their consequences to others restricted by stimulus-response associations. Chronic stressor exposure also desensitizes glucocorticoid receptors (GR) and diminishes motivation to acquire food reinforcement, although causal relationships are largely not established. We show that a history of chronic exposure to the GR ligand corticosterone or acute posttraining GR blockade with RU38486 makes rodents less able to perform actions based on their consequences. Thus, optimal GR binding is necessary for the consolidation of new response-outcome learning. In contrast, medial prefrontal (but not striatal) BDNF can account for stress-related amotivation, in that selective medial prefrontal cortical Bdnf knockdown decreases break-point ratios in a progressive-ratio task. Knockdown also increases vulnerability to RU38486. Despite the role of BDNF in dendritic spine reorganization, deep-layer spine remodeling does not obviously parallel progressive-ratio response patterns, but treatment with the Na(+)-channel inhibitor riluzole reverses corticosteroid-induced motivational deficits and restores prefrontal BDNF expression after corticosterone. We argue that when prefrontal neurotrophin systems are compromised, and GR-mediated hypothalamic-pituitary-adrenal axis feedback is desensitized (as in the case of chronic stress hormone exposure), amotivation and inflexible maladaptive response strategies that contribute to stress-related mood disorders result. PMID:23185000

  1. High dose zinc supplementation induces hippocampal zinc deficiency and memory impairment with inhibition of BDNF signaling.

    Directory of Open Access Journals (Sweden)

    Yang Yang

    Full Text Available Zinc ions highly concentrate in hippocampus and play a key role in modulating spatial learning and memory. At a time when dietary fortification and supplementation of zinc have increased the zinc consuming level especially in the youth, the toxicity of zinc overdose on brain function was underestimated. In the present study, weaning ICR mice were given water supplemented with 15 ppm Zn (low dose, 60 ppm Zn (high dose or normal lab water for 3 months, the behavior and brain zinc homeostasis were tested. Mice fed high dose of zinc showed hippocampus-dependent memory impairment. Unexpectedly, zinc deficiency, but not zinc overload was observed in hippocampus, especially in the mossy fiber-CA3 pyramid synapse. The expression levels of learning and memory related receptors and synaptic proteins such as NMDA-NR2A, NR2B, AMPA-GluR1, PSD-93 and PSD-95 were significantly decreased in hippocampus, with significant loss of dendritic spines. In keeping with these findings, high dose intake of zinc resulted in decreased hippocampal BDNF level and TrkB neurotrophic signaling. At last, increasing the brain zinc level directly by brain zinc injection induced BDNF expression, which was reversed by zinc chelating in vivo. These results indicate that zinc plays an important role in hippocampus-dependent learning and memory and BDNF expression, high dose supplementation of zinc induces specific zinc deficiency in hippocampus, which further impair learning and memory due to decreased availability of synaptic zinc and BDNF deficit.

  2. Widespread expression of BDNF but not NT3 by target areas of basal forebrain cholinergic neurons

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, H.S.; Hains, J.M.; Laramee, G.R.; Rosenthal, A.; Winslow, J.W. (Genentech, San Francisco, CA (USA))

    1990-10-12

    Brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT3) are homologs of the well-known neurotrophic factor nerve growth factor. The three members of this family display distinct patterns of target specificity. To examine the distribution in brain of messenger RNA for these molecules, in situ hybridization was performed. Cells hybridizing intensely to antisense BDNF probe were located throughout the major targets of the rat basal forebrain cholinergic system, that is, the hippocampus, amygdala, and neocortex. Strongly hybridizing cells were also observed in structures associated with the olfactory system. The distribution of NT3 mRNA in forebrain was much more limited. Within the hippocampus, labeled cells were restricted to CA2, the most medial portion of CA1, and the dentate gyrus. In human hippocampus, cells expressing BDNF and mRNA are distributed in a fashion similar to that observed in the rat. These findings point to both basal forebrain cholinergic cells and olfactory pathways as potential central targets for BDNF.

  3. AT2-receptor stimulation enhances axonal plasticity after spinal cord injury by upregulating BDNF expression

    DEFF Research Database (Denmark)

    Namsolleck, Pawel; Boato, Francesco; Schwengel, Katja;

    2013-01-01

    outgrowth was absent in neurons derived from AT2R-KO mice. In primary neurons, treatment with C21 further induced RNA expression of anti-apoptotic Bcl-2 (+75.7%), brain-derived neurotrophic factor (BDNF) (+53.7%), the neurotrophin receptors TrkA (+57.4%) and TrkB (+67.9%) and a marker for neurite growth...

  4. Yueju Pill Rapidly Induces Antidepressant-Like Effects and Acutely Enhances BDNF Expression in Mouse Brain

    Directory of Open Access Journals (Sweden)

    Wenda Xue

    2013-01-01

    Full Text Available The traditional antidepressants have a major disadvantage in delayed onset of efficacy, and the emerging fast-acting antidepressant ketamine has adverse behavioral and neurotoxic effects. Yueju pill, an herb medicine formulated eight hundred years ago by Doctor Zhu Danxi, has been popularly prescribed in China for alleviation of depression-like symptoms. Although several clinical outcome studies reported the relative short onset of antidepressant effects of Yueju, this has not been scientifically investigated. We, therefore, examined the rapid antidepressant effect of Yueju in mice and tested the underlying molecular mechanisms. We found that acute administration of ethanol extract of Yueju rapidly attenuated depressive-like symptoms in learned helpless paradigm, and the antidepressant-like effects were sustained for at least 24 hours in tail suspension test in ICR mice. Additionally, Yueju, like ketamine, rapidly increased the expression of brain-derived neurotrophic factor (BDNF in the hippocampus, whereas the BDNF mRNA expression remained unaltered. Yueju rapidly reduced the phosphorylation of eukaryotic elongation factor 2 (eEF2, leading to desuppression of BDNF synthesis. Unlike ketamine, both the BDNF expression and eEF2 phosphorylation were revered at 24 hours after Yueju administration. This study is the first to demonstrate the rapid antidepressant effects of an herb medicine, offering an opportunity to improve therapy of depression.

  5. Camouflage mimetico e il problema della rappresentazione pittorica / Mimetic Camouflage and the Problem of Pictorial Representation

    OpenAIRE

    Méndez Baiges, Maite

    2015-01-01

    A hundred years ago , during the I World War, the first forms of military camouflage were devoloped. The earlier Unité de Camouflage was born in February 1915 in the french army. Mimetic camouflage design, called Disruptive Pattern Material (DPM), was the product of an intention of deceit based on concealment of equipment and facilities against the enemy. These primitive forms of invisibility searched the mimesis with the environment, and they developed both abstract and figurative solutions....

  6. Female preferences drive the evolution of mimetic accuracy in male sexual displays

    OpenAIRE

    Coleman, Seth William; Patricelli, Gail Lisa; Coyle, Brian; Siani, Jennifer; Borgia, Gerald

    2007-01-01

    Males in many bird species mimic the vocalizations of other species during sexual displays, but the evolutionary and functional significance of interspecific vocal mimicry is unclear. Here we use spectrographic cross-correlation to compare mimetic calls produced by male satin bowerbirds (Ptilonorhynchus violaceus) in courtship with calls from several model species. We show that the accuracy of vocal mimicry and the number of model species mimicked are both independently related to male mating...

  7. Physics of cell adhesion: some lessons from cell-mimetic systems

    OpenAIRE

    Sackmann, Erich; Smith, Ana-Sunčana

    2014-01-01

    Cell adhesion is a paradigm of the ubiquitous interplay of cell signalling, modulation of material properties and biological functions of cells. It is controlled by competition of short range attractive forces, medium range repellant forces and the elastic stresses associated with local and global deformation of the composite cell envelopes. We review the basic physical rules governing the physics of cell adhesion learned by studying cell-mimetic systems and demonstrate the importance of thes...

  8. Mechanisms of heparanase inhibition by the heparan sulfate mimetic PG545 and three structural analogues ☆

    OpenAIRE

    Hammond, Edward; Handley, Paul; Dredge, Keith; Bytheway, Ian

    2013-01-01

    The tetrasaccharide heparan sulfate (HS) mimetic PG545, a clinical anti-cancer candidate, is an inhibitor of the HS-degrading enzyme heparanase. The kinetics of heparanase inhibition by PG545 and three structural analogues were investigated to understand their modes of inhibition. The cholestanol aglycon of PG545 significantly increased affinity for heparanase and also modified the inhibition mode. For the tetrasaccharides, competitive inhibition was modified to parabolic competition by the a...

  9. A mimetic spectral element solver for the Grad-Shafranov equation

    CERN Document Server

    Palha, Artur; Felici, Federico

    2015-01-01

    In this work we present a robust and accurate arbitrary order solver for the fixed-boundary plasma equilibria in toroidally axisymmetric geometries. To achieve this we apply the mimetic spectral element formulation presented in [56] to the solution of the Grad-Shafranov equation. This approach combines a finite volume discretization with the mixed finite element method. In this way the discrete differential operators ($\

  10. A unified approach to Mimetic Finite Difference, Hybrid Finite Volume and Mixed Finite Volume methods

    OpenAIRE

    Droniou, Jerome; Eymard,, Robert; Gallouët, Thierry; Herbin, Raphaele

    2008-01-01

    International audience We investigate the connections between several recent methods for the discretization of ani\\-so\\-tropic heterogeneous diffusion operators on general grids. We prove that the Mimetic Finite Difference scheme, the Hybrid Finite Volume scheme and the Mixed Finite Volume scheme are in fact identical up to some slight generalizations. As a consequence, some of the mathematical results obtained for each of the method (such as convergence properties or error estimates) may ...

  11. Supramolecular assembly of electrostatically stabilized, hydroxyproline-lacking collagen-mimetic peptides

    OpenAIRE

    Krishna, Ohm D.; Kiick, Kristi L.

    2009-01-01

    The mechanical and biological functions of the native collagens remain an inspiration in materials design, but widespread application of de novo collagens has been limited in part by the need for hydroxylated proline in the formation of stable triple helical structures. In order to address this continued need and to expand the potential for recombinant expression of functional, hydroxyproline-lacking collagen-mimetic peptides, we have designed a hydrophilic, non-repetitive, and thermally stab...

  12. Template-Tethered Collagen Mimetic Peptides for Studying Heterotrimeric Triple-Helical Interactions

    OpenAIRE

    Li, Yang; Mo, Xiao; Kim, Daniel; Yu, S. Michael

    2010-01-01

    Collagen mimetic peptides (CMPs) have been used to elucidate the structure and stability of the triple helical conformation of collagen molecules. Although CMP homotrimers have been widely studied, very little work has been reported regarding CMP heterotrimers because of synthetic difficulties. Here we present the synthesis and characterization of homotrimers and ABB type heterotrimers comprising natural and synthetic CMP sequences that are covalently tethered to a template, a tris(2-aminoeth...

  13. Aerodynamic Bio-Mimetics of Gliding Dragonflies for Ultra-Light Flying Robot

    OpenAIRE

    Akira Obata; Shotarou Shinohara; Kyohei Akimoto; Kakeru Suzuki; Miyuki Seki

    2014-01-01

    A detailed investigation including a low-speed flow study is presented on the development of ultra-light dragonfly mimetic flying robots with a focus on the dragonfly’s remarkable gliding capability. It is revealed that the dragonfly’s corrugated wing structure and cruciform configuration provide superior flying characteristics for fixed wing robots in low Reynolds number flight. It was also found that the dragonfly configuration has additional merit in its compatibility with propellers or hi...

  14. Modified Gauss-Bonnet gravity with Lagrange multiplier constraint as mimetic theory

    OpenAIRE

    Astashenok, Artyom V.; Odintsov, Sergei D.; Oikonomou, V.K.

    2015-01-01

    In this paper we propose and extensively study mimetic $f({\\cal G})$ modified gravity models, with various scenarios of cosmological evolution, with or without extra matter fluids. The easiest formulation is based on the use of Lagrange multiplier constraint. In certain versions of this theory, it is possible to realize accelerated expansion of the Universe or even unified evolution which includes inflation with dark energy, and at the same time in the same theoretical framework, dark matter ...

  15. Associations between parenting behavior and anxiety in a rodent model and a clinical sample: relationship to peripheral BDNF levels.

    Science.gov (United States)

    Dalle Molle, R; Portella, A K; Goldani, M Z; Kapczinski, F P; Leistner-Segal, S; Leistner-Segala, S; Salum, G A; Manfro, G G; Silveira, P P

    2012-01-01

    Adverse early-life environment is associated with anxiety-like behaviors and disorders. Brain-derived neurotrophic factor (BDNF) is sensitive to this environment and could be a marker of underlying brain changes. We aimed at evaluating the development of anxiety-like behaviors in a rat model of early adversity, as well as the possible association with BDNF levels. Similar associations were investigated in a sample of adolescent humans. For the rat study, Wistar rat litters were divided into: early-life stress (ELS, limited access to nesting material) and control groups. Maternal behavior was observed from days 1 to 9 of life and, as adults, rats were subjected to behavioral testing and BDNF measurements in plasma, hippocampus, amygdala and periaqueductal gray. For the human study, 129 adolescents were evaluated for anxiety symptoms and perceived parental care. Serum BDNF levels and the Val66Met polymorphism of the BDNF gene were investigated. We found that ELS dams showed more pure contact, that is, contact with low care and high control, toward pups, and their adult offspring demonstrated higher anxiety-like behaviors and plasma BDNF. Also the pure contact correlated positively with adult peripheral BDNF. Similarly in humans, there was a positive correlation between maternal overprotection and serum BDNF only in Met carriers. We also found negative correlations between maternal warmth and separation anxiety, social phobia and school phobia. Finally, our translational approach revealed that ELS, mediated through variations in maternal care, is associated with anxiety in both rats and humans and increased peripheral BDNF may be marking these phenomena.

  16. Bio-mimetic mineralization potential of collagen hydrolysate obtained from chromium tanned leather waste.

    Science.gov (United States)

    Banerjee, Pradipta; Madhu, S; Chandra Babu, N K; Shanthi, C

    2015-04-01

    Hydroxyapatite (HA) ceramics serve as an alternative to autogenous-free bone grafting by virtue of their excellent biocompatibility. However, chemically synthesized HA lacks the strong load-bearing capacity as required by bone. The bio-mimetic growth of HA crystals on collagen surface provides a feasible solution for synthesizing bone substitutes with the desired properties. This study deals with the utilization of the collagen hydrolysate recovered from leather waste as a substrate for promoting HA crystal growth. Bio-mimetic growth of HA was induced by subjecting the hydrolysate to various mineralization conditions. Parameters that would have a direct effect on crystal growth were varied to determine the optimal conditions necessary. Maximum mineralization was achieved with a combination of 10mM of CaCl2, 5mM of Na2HPO4, 100mM of NaCl and 0.575% glutaraldehyde at a pH of 7.4. The metal-protein interactions leading to formation of HA were identified through Fourier-transform infrared (FTIR) spectroscopy and x-ray diffraction (XRD) studies. The crystal dimensions were determined to be in the nanoscale range by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The size and crystallinity of bio-mimetically grown HA indicate that hydrolysate from leather waste can be used as an ideal alternative substrate for bone growth.

  17. Interactions of Bio-Inspired Membranes with Peptides and Peptide-Mimetic Nanoparticles

    Directory of Open Access Journals (Sweden)

    Michael Sebastiano

    2015-08-01

    Full Text Available Via Dissipative Particle Dynamics (DPD and implicit solvent coarse-grained (CG Molecular Dynamics (MD we examine the interaction of an amphiphilic cell-penetrating peptide PMLKE and its synthetic counterpart with a bio-inspired membrane. We use the DPD technique to investigate the interaction of peptide-mimetic nanoparticles, or nanopins, with a three-component membrane. The CG MD approach is used to investigate the interaction of a cell-penetrating peptide PMLKE with single-component membrane. We observe the spontaneous binding and subsequent insertion of peptide and nanopin in the membrane by using CG MD and DPD approaches, respectively. In addition, we find that the insertion of peptide and nanopins is mainly driven by the favorable enthalpic interactions between the hydrophobic components of the peptide, or nanopin, and the membrane. Our study provides insights into the mechanism underlying the interactions of amphiphilic peptide and peptide-mimetic nanoparticles with a membrane. The result of this study can be used to guide the functional integration of peptide and peptide-mimetic nanoparticles with a cell membrane.

  18. Aspects of Late-time Evolution in Mimetic $F(R)$ Gravity

    CERN Document Server

    Oikonomou, V K

    2016-01-01

    We demonstrate how to describe in an unified way early and late-time acceleration in the context of mimetic $F(R)$ gravity. As we show, an exponential $F(R)$ gravity model has appealing features, with regard to unification, and we perform an analysis of the late-time evolution. The resulting picture is interesting since in the mimetic case, certain pathologies of some ordinary $F(R)$ models are remedied in a consistent way, owing to the presence of the mimetic potential and the Lagrange multiplier. We quantify the late-time evolution analysis by studying the scaled dark energy density, the dark energy equation of state and the total effective equation of state, and as we show the late-time evolution is crucially affected by the functional form of the $F(R)$ gravity. It is intriguing that the most appealing case corresponds to the exponential $F(R)$ gravity which unifies late and early-time acceleration. Finally, we study the behavior of the effective gravitational constant and the growth factor, and as we sho...

  19. Manipulation of health span and function by dietary caloric restriction mimetics.

    Science.gov (United States)

    Roth, George S; Ingram, Donald K

    2016-01-01

    After nearly a century of rigorous investigation and testing, dietary caloric restriction (CR) remains the most robust and reproducible method for slowing aging and maintaining health, function, and vitality. This intervention has been applied to species across the evolutionary spectrum, but for a number of reasons, practical applicability to humans has been questioned. To overcome these issues, we initiated the field of CR mimetics in 1998 and have observed its development into a full-fledged antiaging industry. Basically, strategies that enable individuals to obtain the biological benefits of CR without reducing actual food intake can be considered CR mimetics, whether functional, pharmaceutical, nutraceutical, or other. Some of the best known candidates include resveratrol and related agents, the antidiabetic drug metformin, and rapamycin and other mTOR regulators. While the mechanisms of action vary, these and essentially all CR mimetic candidates work through at least some of the same pathways as actual CR. While the entire field continues to evolve rapidly, the current status will be reviewed here, with particular focus on recent developments, the most practical relevance and applicability for potential consumers, and new strategies for the future. PMID:26214681

  20. Smac mimetic-derived augmentation of chemotherapeutic response in experimental pancreatic cancer

    International Nuclear Information System (INIS)

    Pancreatic ductal adenocarcinoma (PDAC) is highly resistant to conventional chemotherapy, in part due to the overexpression of inhibitors of apoptosis proteins (IAPs). Smac is an endogenous IAP-antagonist, which renders synthetic Smac mimetics attractive anticancer agents. We evaluated the benefits of combining a Smac mimetic, JP1201 (JP), with conventional chemotherapy agents used for PDAC management. Cell viability assays and protein expression analysis were performed using WST-1 reagent and Western blotting, respectively. Apoptosis was detected by annexin V/propidium iodide staining. In vivo tumor growth and survival studies were performed in murine PDAC xenografts. JP and gemcitabine (Gem) inhibited PDAC cell proliferation with additive effects in combination. The percentage of early apoptotic cells in controls, JP, Gem and JP + Gem was 17%, 26%, 26% and 38%, respectively. JP-induced apoptosis was accompanied by PARP-1 cleavage. Similar additive anti-proliferative effects were seen for combinations of JP with doxorubicin (Dox) and docetaxel (DT). The JP + Gem combination caused a 30% decrease in tumor size in vivo compared to controls. Median animal survival was improved significantly in mice treated with JP + Gem (38 d) compared to controls (22 d), JP (28 d) or Gem (32 d) (p = 0.01). Animal survival was also improved with JP + DT treatment (32 d) compared to controls (16 d), JP (21 d) or DT alone (27 d). These results warrant further exploration of strategies that promote chemotherapy-induced apoptosis of tumors and highlight the potential of Smac mimetics in clinical PDAC therapy

  1. Early life stress increases stress vulnerability through BDNF gene epigenetic changes in the rat hippocampus.

    Science.gov (United States)

    Seo, Mi Kyoung; Ly, Nguyen Ngoc; Lee, Chan Hong; Cho, Hye Yeon; Choi, Cheol Min; Nhu, Le Hoa; Lee, Jung Goo; Lee, Bong Ju; Kim, Gyung-Mee; Yoon, Bong June; Park, Sung Woo; Kim, Young Hoon

    2016-06-01

    Early life stress (ELS) exerts long-lasting epigenetic influences on the brain and makes an individual susceptible to later depression. It is poorly understood whether ELS and subsequent adult chronic stress modulate epigenetic mechanisms. We examined the epigenetic mechanisms of the BDNF gene in the hippocampus, which may underlie stress vulnerability to postnatal maternal separation (MS) and adult restraint stress (RS). Rat pups were separated from their dams (3 h/day from P1-P21). When the pups reached adulthood (8 weeks old), we introduced RS (2 h/day for 3 weeks) followed by escitalopram treatment. We showed that both the MS and RS groups expressed reduced levels of total and exon IV BDNF mRNA. Furthermore, RS potentiated MS-induced decreases in these expression levels. Similarly, both the MS and RS groups showed decreased levels of acetylated histone H3 and H4 at BDNF promoter IV, and RS exacerbated MS-induced decreases of H3 and H4 acetylation. Both the MS and RS groups had increased MeCP2 levels at BDNF promoter IV, as well as increased HDAC5 mRNA, and the combination of MS and RS exerted a greater effect on these parameters than did RS alone. In the forced swimming test, the immobility time of the MS + RS group was significantly higher than that of the RS group. Additionally, chronic escitalopram treatment recovered these alterations. Our results suggest that postnatal MS and subsequent adult RS modulate epigenetic changes in the BDNF gene, and that these changes may be related to behavioral phenotype. These epigenetic mechanisms are involved in escitalopram action. PMID:26877199

  2. An updated review on cancer risk associated with incretin mimetics and enhancers.

    Science.gov (United States)

    Tseng, Chin-Hsiao; Lee, Kuo-Yang; Tseng, Farn-Hsuan

    2015-01-01

    Incretin-based therapies, including the use of incretin mimetics of glucagon-like peptide-1 receptor (GLP-1R) agonists and incretin enhancers of dipeptidyl-peptidase 4 (DPP-4) inhibitors, are widely used by clinicians for glucose lowering in patients with type 2 diabetes mellitus. These agents have benefits of a lower risk of hypoglycemia, being neutral for body weight for DPP-4 inhibitors and having a potential for weight reduction with GLP-1R agonists. They may also have a neutral or beneficial cardiovascular effect. Despite these benefits, an increased risk of cancer (especially pancreatic cancer and thyroid cancer) associated with incretin-based therapies has been reported. In this article, we reviewed related literature of experimental animal and observational human studies, clinical trials, and meta-analyses published until December 15, 2014. Current studies suggested a probable role of GLP-1R activation on the development of pancreatic cancer and thyroid cancer in rodents, but such an effect in humans is not remarkable due to the lower or lack of expression of GLP-1R on human pancreatic ductal cells and thyroid tissues. Findings in human studies are controversial and inconclusive. In the analyses of the US Food and Drug Administration adverse events reporting system, a significantly higher risk of pancreatic cancer was observed for GLP-1R agonists and DPP-4 inhibitors, but a significantly higher risk of thyroid cancer was only observed for GLP-1R agonists. Such a higher risk of pancreatic cancer or thyroid cancer could not be similarly demonstrated in other human observational studies or analyses of data from clinical trials. With regards to cancers other than pancreatic cancer and thyroid cancer, available studies supported a neutral association in humans. Some preliminary studies even suggested a potentially beneficial effect on the development of other cancers with the use of incretins. Based on current evidence, continuous monitoring of the cancer issues

  3. Development of electrospun bone-mimetic matrices for bone regenerative applications

    Science.gov (United States)

    Phipps, Matthew Christopher

    Although bone has a dramatic capacity for regeneration, certain injuries and procedures present defects that are unable to heal properly, requiring surgical intervention to induce and support osteoregeneration. Our research group has hypothesized that the development of a biodegradable material that mimics the natural composition and architecture of bone extracellular matrix has the potential to provide therapeutic benefit to these patients. Utilizing a process known as electrospinning, our lab has developed a bone-mimetic matrix (BMM) consisting of composite nanofibers of the mechanically sta-ble polymer polycaprolactone (PCL), and the natural bone matrix molecules type-I colla-gen and hydroxyapatite nanocrystals (HA). We herein show that BMMs supported great-er adhesion, proliferation, and integrin activation of mesenchymal stem cells (MSCs), the multipotent bone-progenitor cells within bone marrow and the periosteum, in comparison to electrospun PCL alone. These cellular responses, which are essential early steps in the process of bone regeneration, highlight the benefits of presenting cells with natural bone molecules. Subsequently, evaluation of new bone formation in a rat cortical tibia defect showed that BMMs are highly osteoconductive. However, these studies also revealed the inability of endogenous cells to migrate within electrospun matrices due to the inherently small pore sizes. To address this limitation, which will negatively impact the rate of scaf-fold-to-bone turnover and inhibit vascularization, sacrificial fibers were added to the ma-trix. The removal of these fibers after fabrication resulted in BMMs with larger pores, leading to increased infiltration of MSCs and endogenous bone cells. Lastly, we evaluat-ed the potential of our matrices to stimulate the recruitment of MSCs, a vital step in bone healing, through the sustained delivery of platelet derived growth factor-BB (PDGF-BB). BMMs were found to adsorb and subsequently release greater

  4. A Smac-mimetic sensitizes prostate cancer cells to TRAIL-induced apoptosis via modulating both IAPs and NF-kappaB

    International Nuclear Information System (INIS)

    Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising agent for human cancer therapy, prostate cancer still remains resistant to TRAIL. Both X-linked inhibitor of apoptosis (XIAP) and nuclear factor-kappaB function as key negative regulators of TRAIL signaling. In this study, we evaluated the effect of SH122, a small molecule mimetic of the second mitochondria-derived activator of caspases (Smac), on TRAIL-induced apoptosis in prostate cancer cells. The potential of Smac-mimetics to bind XIAP or cIAP-1 was examined by pull-down assay. Cytotoxicity of TRAIL and/or Smac-mimetics was determined by a standard cell growth assay. Silencing of XIAP or cIAP-1 was achieved by transient transfection of short hairpin RNA. Apoptosis was detected by Annexin V-PI staining followed by flow cytometry and by Western Blot analysis of caspases, PARP and Bid. NF-kappaB activation was determined by subcellular fractionation, real time RT-PCR and reporter assay. SH122, but not its inactive analog, binds to XIAP and cIAP-1. SH122 significantly sensitized prostate cancer cells to TRAIL-mediated cell death. Moreover, SH122 enhanced TRAIL-induced apoptosis via both the death receptor and the mitochondrial pathway. Knockdown of both XIAP and cIAP-1 sensitized cellular response to TRAIL. XIAP-knockdown attenuated sensitivity of SH122 to TRAIL-induced cytotoxicity, confirming that XIAP is an important target for IAP-inhibitor-mediated TRAIL sensitization. SH122 also suppressed TRAIL-induced NF-kappaB activation by preventing cytosolic IkappaB-alpha degradation and RelA nuclear translocation, as well as by suppressing NF-kappaB target gene expression. These results demonstrate that SH122 sensitizes human prostate cancer cells to TRAIL-induced apoptosis by mimicking Smac and blocking both IAPs and NF-kappaB. Modulating IAPs may represent a promising approach to overcoming TRAIL-resistance in human prostate cancer with constitutively active NF-kappaB signaling

  5. Improved surface bioactivity of stainless steel substrates using osteocalcin mimetic peptide

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini, Samaneh [Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Tissue Engineering and Biomaterials Division, National Institute of Genetic Engineering and Biotechnology, Tehran 14965/161 (Iran, Islamic Republic of); Naderi-Manesh, Hossein, E-mail: naderman@modares.ac.ir [Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Vali, Hojatollah [Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montréal, QC H3A 0C7 (Canada); Faghihi, Shahab, E-mail: sfaghihi@nigeb.ac.ir [Tissue Engineering and Biomaterials Division, National Institute of Genetic Engineering and Biotechnology, Tehran 14965/161 (Iran, Islamic Republic of)

    2014-02-14

    Although stainless steel has a good biocompatibility for most clinical cases, the higher tissue response (bone bonding property) is required in orthopedic field. In this study, to improve bone-bonding ability of stainless steel substrates, a specific sequence of osteocalcin mimetic peptide is used as bioactive coating material to biochemically modify the surface of metallic samples. This sequence consists of thirteen amino acids present in the first helix of osteocalcin is synthesized in amidic form and physically adsorbed on the surface of 316LS (316 low carbon surgical grade) stainless steel substrates. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) are used to characterize the surface of peptide coated and uncoated substrates. The bioactivity and bone bonding ability of coated and uncoated substrates are assessed by level of hydroxyapatite formation, using transmission electron microscopy (TEM), energy-dispersive x-ray (EDS), and scanning electron microscopy (SEM). The pre-osteoblast cell attachment and proliferation are also evaluated by MTT assay. The results show that the surface of coated sample is homogenously covered by the peptide and display a rougher surface relative to uncoated sample. TEM images reveal the formation of plate-like hydroxyapatite crystals in the presence of the peptide and an amorphous calcium phosphate phase without the peptide. Pre-osteoblast cells proliferation is significantly higher on the surface of peptide coated substrate, while cell attachment remains unaffected by the peptide coatings. Pre-osteoblast cells also demonstrate a higher degree of spreading on the surface of coated sample. It is believed that osteocalcin mimetic peptide improve surface bioactivity and promote hydroxyapatite crystal formation may lead to increased mineralization and bone formation on the surface of metallic biomedical devices. - Graphical abstract: A peptide sequence located in the first helix of OC is selected based on its

  6. Establishment of A Real Time Method for Detecting the Expression of BDNF mRNA Gene%Real time RT-PCR定量检测BDNF mRNA表达水平方法的建立

    Institute of Scientific and Technical Information of China (English)

    杨克红; 许冰莹; 葛树星; 闫俊岭; 卢珊珊; 吴兰鸥

    2007-01-01

    目的 建立real time 逆转录聚合酶链反应(RT-PCR)检测BDNF mRNA基因表达的方法.方法 提取脑缺血组织的总RNA,进行RT-PCR扩增BDNF mRNA特异性片段,扩增产物重组到质粒上并测序,建立real time RT-PCR检测BDNF mRNA表达水平方法.结果 重组的质粒经酶切和测序,目的 片段已插入到载体内,得到real time RT-PCR动力学曲线.结论 成功建立real time RT-PCR检测BDNF mRNA基因表达的方法.

  7. Targeted delivery of a model immunomodulator to the lymphatic system: comparison of alkyl ester versus triglyceride mimetic lipid prodrug strategies.

    Science.gov (United States)

    Han, Sifei; Quach, Tim; Hu, Luojuan; Wahab, Anisa; Charman, William N; Stella, Valentino J; Trevaskis, Natalie L; Simpson, Jamie S; Porter, Christopher J H

    2014-03-10

    lymphatics and lymphocytes. Importantly, after administration of 2-MPA-TG, the concentrations of free MPA in the mesenteric lymph nodes were significantly enhanced (up to 28 fold) when compared to animals administered equimolar quantities of MPA, suggesting the efficient conversion of the esterified prodrug back to the pharmacologically active parent drug. The data suggest that triglyceride mimetic prodrugs have potential as a means of enhancing immunotherapy via drug targeting to lymphocytes and lymph nodes.

  8. Targeted delivery of a model immunomodulator to the lymphatic system: comparison of alkyl ester versus triglyceride mimetic lipid prodrug strategies.

    Science.gov (United States)

    Han, Sifei; Quach, Tim; Hu, Luojuan; Wahab, Anisa; Charman, William N; Stella, Valentino J; Trevaskis, Natalie L; Simpson, Jamie S; Porter, Christopher J H

    2014-03-10

    lymphatics and lymphocytes. Importantly, after administration of 2-MPA-TG, the concentrations of free MPA in the mesenteric lymph nodes were significantly enhanced (up to 28 fold) when compared to animals administered equimolar quantities of MPA, suggesting the efficient conversion of the esterified prodrug back to the pharmacologically active parent drug. The data suggest that triglyceride mimetic prodrugs have potential as a means of enhancing immunotherapy via drug targeting to lymphocytes and lymph nodes. PMID:24398334

  9. Ultra-sensitive detection of brain-derived neurotrophic factor (BDNF) in the brain of freely moving mice using an interdigitated microelectrode (IME) biosensor.

    Science.gov (United States)

    Yoo, Yong Kyoung; Lee, Jaekwang; Kim, Jinsik; Kim, Gangeun; Kim, Sunpil; Kim, Jeongyeon; Chun, Heejung; Lee, Jeong Hoon; Lee, C Justin; Hwang, Kyo Seon

    2016-01-01

    Brain-derived neurotrophic factor (BDNF) plays a critical role in cognitive processes including learning and memory. However, it has been difficult to detect BDNF in the brains of behaving animals because of its extremely low concentration, i.e., at the sub-nanogram/mL level. Here, we developed an interdigitated microelectrode (IME) biosensor coated with an anti-BDNF an anti-BDNF antibody in a polydimethylsiloxane (PDMS)-based microfluidic channel chip. This sensor could detect BDNF from microliter volumes of liquid samples even at femtogram/mL concentrations with high selectivity over other growth factors. Using this biosensor, we examined whether BDNF is detectable from periodical collection of cerebrospinal fluid microdialysate, sampled every 10 min from the hippocampus of mice during the context-dependent fear-conditioning test. We found that the IME biosensor could detect a significant increase in BDNF levels after the memory task. This increase in BDNF levels was prevented by gene silencing of BDNF, indicating that the IME biosensor reliably detected BDNF in vivo. We propose that the IME biosensor provides a general-purpose probe for ultrasensitive detection of biomolecules with low abundance in the brains of behaving animals. PMID:27640722

  10. Pharmacological profile of brain-derived neurotrophic factor (BDNF) splice variant translation using a novel drug screening assay: a "quantitative code".

    Science.gov (United States)

    Vaghi, Valentina; Polacchini, Alessio; Baj, Gabriele; Pinheiro, Vera L M; Vicario, Annalisa; Tongiorgi, Enrico

    2014-10-01

    The neurotrophin brain-derived neurotrophic factor (BDNF) is a key regulator of neuronal development and plasticity. BDNF is a major pharmaceutical target in neurodevelopmental and psychiatric disorders. However, pharmacological modulation of this neurotrophin is challenging because BDNF is generated by multiple, alternatively spliced transcripts with different 5'- and 3'UTRs. Each BDNF mRNA variant is transcribed independently, but translation regulation is unknown. To evaluate the translatability of BDNF transcripts, we developed an in vitro luciferase assay in human neuroblastoma cells. In unstimulated cells, each BDNF 5'- and 3'UTR determined a different basal translation level of the luciferase reporter gene. However, constructs with either a 5'UTR or a 3'UTR alone showed poor translation modulation by BDNF, KCl, dihydroxyphenylglycine, AMPA, NMDA, dopamine, acetylcholine, norepinephrine, or serotonin. Constructs consisting of the luciferase reporter gene flanked by the 5'UTR of one of the most abundant BDNF transcripts in the brain (exons 1, 2c, 4, and 6) and the long 3'UTR responded selectively to stimulation with the different receptor agonists, and only transcripts 2c and 6 were increased by the antidepressants desipramine and mirtazapine. We propose that BDNF mRNA variants represent "a quantitative code" for regulated expression of the protein. Thus, to discriminate the efficacy of drugs in stimulating BDNF synthesis, it is appropriate to use variant-specific in vitro screening tests.

  11. Expressions of brain-derived neurotrophic factor (BDNF) in cerebrospinal fluid and plasma of children with meningitis and encephalitis/encephalopathy.

    Science.gov (United States)

    Morichi, Shinichiro; Kashiwagi, Yasuyo; Takekuma, Koji; Hoshika, Akinori; Kawashima, Hisashi

    2013-01-01

    Many reports in the field of childhood brain disorders have documented that brain-derived neurotrophic factor (BDNF) affects central nervous system (CNS) functions. In this clinical study, BDNF levels were evaluated in association with pediatric CNS infections. BDNF levels in the serum and cerebrospinal fluid (CSF) of 42 patients admitted during 5-year period, due to CNS infections, were measured by enzyme-linked immunosorbent assays (ELISAs). Control samples were collected from 108 patients with non-CNS infections (urinary tract infection, acute upper respiratory infection, acute gastroenteritis, etc.). Mean values of BDNF levels, at various ages, were determined and compared. BDNF levels were below the sensitivity of the ELISA in most CSF samples from the control group, but were significantly elevated in the patients with bacterial meningitis. The serum BDNF levels were elevated in all subgroups of patients with CNS infections, and the elevation was particularly notable in those with bacterial meningitis. BDNF expression in the CSF was correlated with CSF interleukin (IL)-6 levels as well as with blood platelet counts and neurological prognoses in those with bacterial meningitis. No correlation was found between BDNF levels and serum leukocyte numbers or C-reactive protein (CRP) levels. BDNF levels were found to be elevated in the serum and CSF of pediatric patients with CNS infections, particularly those with bacterial meningitis. Monitoring the changes in serum and CSF levels of BDNF may facilitate the diagnosis of acute meningitis and acute encephalopathy and allow the differential diagnosis of specific CNS infections.

  12. Alterations in brain-derived neurotrophic factor (BDNF) and its precursor proBDNF in the brain regions of a learned helplessness rat model and the antidepressant effects of a TrkB agonist and antagonist.

    Science.gov (United States)

    Shirayama, Yukihiko; Yang, Chun; Zhang, Ji-chun; Ren, Qian; Yao, Wei; Hashimoto, Kenji

    2015-12-01

    Role of brain-derived neurotrophic factor (BDNF)-TrkB signaling in a learned helplessness (LH) model of depression was investigated. LH rats showed a reduction of BDNF in the medial prefrontal cortex (mPFC), CA3, and dentate gyrus (DG) of the hippocampus, whereas LH rats showed an increase in BDNF in the nucleus accumbens (NAc). Furthermore, levels of proBDNF, a BDNF precursor, were higher in the mPFC, but lower in the NAc, of LH rats. A single bilateral infusion of a TrkB agonist 7,8-DHF, but not a TrkB antagonist ANA-12, into the infralimbic (IL) of mPFC, DG, and CA3, but not the prelimbic (PrL) of mPFC, exerted antidepressant effects in LH rats. In contrast, a single bilateral infusion of ANA-12, but not 7,8-DHF, into the core and shell of NAc exerted antidepressant-like effects in LH rats, with more potent effects observed for the NAc core than for NAc shell. Interestingly, a single administration of 7,8-DHF (10mg/kg, i.p.) significantly improved a decreased phosphorylation of TrkB in the mPFC, CA3, and DG of LH rats. Additionally, ANA-12 (0.5mg/kg, i.p.) significantly improved an increased phosphorylation of TrkB in the NAc of LH rats. In conclusion, these results suggest that LH causes depression-like behavior by altering BDNF in the brain regions, and that proBDNF-BDNF processing and transport may be altered in the mPFC-NAc circuit of LH rats. Therefore, TrkB agonists might exert antidepressant effects by stimulating TrkB in the IL, CA3, and DG, while TrkB antagonists might exert antidepressant effects by blocking TrkB in the NAc.

  13. Cross-sex hormone treatment in male-to-female transsexual persons reduces serum brain-derived neurotrophic factor (BDNF).

    Science.gov (United States)

    Fuss, Johannes; Hellweg, Rainer; Van Caenegem, Eva; Briken, Peer; Stalla, Günter K; T'Sjoen, Guy; Auer, Matthias K

    2015-01-01

    Serum levels of brain-derived neurotrophic factor (BDNF) are reduced in male-to-female transsexual persons (MtF) compared to male controls. It was hypothesized before that this might reflect either an involvement of BDNF in a biomechanism of transsexualism or to be the result of persistent social stress due to the condition. Here, we demonstrate that 12 month of cross-sex hormone treatment reduces serum BDNF levels in male-to-female transsexual persons independent of anthropometric measures. Participants were acquired through the European Network for the Investigation of Gender Incongruence (ENIGI). Reduced serum BDNF in MtF thus seems to be a result of hormonal treatment rather than a consequence or risk factor of transsexualism.

  14. TiO(2) nanotube arrays: intrinsic peroxidase mimetics.

    Science.gov (United States)

    Zhang, Lingling; Han, Lei; Hu, Peng; Wang, Li; Dong, Shaojun

    2013-11-18

    TiO2 nanotube arrays (NTA), prepared by potentiostatic anodization, were discovered to possess an intrinsic peroxidase-like activity. The colorimetric and electrochemical assays both demonstrated their excellent catalytic activity towards H2O2 reduction. On this basis, a simple and inexpensive electrochemical biosensor for glucose detection was developed. PMID:24084751

  15. Ochre Bathing of the Bearded Vulture: A Bio-Mimetic Model for Early Humans towards Smell Prevention and Health

    Directory of Open Access Journals (Sweden)

    Helmut Tributsch

    2016-01-01

    Full Text Available Since primordial times, vultures have been competing with man for animal carcasses. One of these vultures, the once widespread bearded vulture ( Gypaetus barbatus , has the habit of bathing its polluted feathers and skin in red iron oxide - ochre - tainted water puddles. Why? Primitive man may have tried to find out and may have discovered its advantages. Red ochre, which has accompanied human rituals and everyday life for more than 100,000 years, is not just a simple red paint for decoration or a symbol for blood. As modern experiments demonstrate, it is active in sunlight producing aggressive chemical species. They can kill viruses and bacteria and convert smelly organic substances into volatile neutral carbon dioxide gas. In this way, ochre can in sunlight sterilize and clean the skin to provide health and comfort and make it scentless, a definitive advantage for nomadic meat hunters. This research thus also demonstrates a sanitary reason for the vulture’s habit of bathing in red ochre mud. Prehistoric people have therefore included ochre use into their rituals, especially into those in relation to birth and death. Significant ritual impulses during evolution of man may thus have developed bio-mimetically, inspired from the habits of a vulture. It is discussed how this health strategy could be developed to a modern standard helping to fight antibiotics-resistant bacteria in hospitals.

  16. Functional characterization of solute carrier (SLC) 26/sulfate permease (SulP) proteins in membrane mimetic systems.

    Science.gov (United States)

    Srinivasan, Lakshmi; Baars, Tonie Luise; Fendler, Klaus; Michel, Hartmut

    2016-04-01

    Solute carrier (SLC) 26 or sulfate permease (SulP) anion transporters, belong to a phylogenetically ancient family of secondary active transporters. Members of the family are involved in several human genetic diseases and cell physiological processes. Despite their importance, the substrates for transport by this family of proteins have been poorly characterized. In this study, recombinant StmYchM/DauA, a SulP from Salmonella typhimurium was purified to homogeneity and functionally characterized. StmYchM/DauA was found to be a dimer in solution as determined by size exclusion chromatography coupled to multiple angle light scattering. We report a functional characterization of the SulP proteins in two membrane mimetic systems and reveal a dual nature of anionic substrates for SulP. StmYchM/DauA functionally incorporated into nanodiscs could bind fumarate with millimolar affinities (KD = 4.6 ± 0.29 mM) as detected by intrinsic tryptophan fluorescence quench studies. In contrast, electrophysiological experiments performed in reconstituted liposomes indicate a strong bicarbonate transport in the presence of chloride but no detectable electrogenic fumarate transport. We hence suggest that while SulP acts as an electrogenic bicarbonate transporter, fumarate may serve as substrate under different conditions indicating multiple functions of SulP. PMID:26774215

  17. BH3 mimetic ABT-737 sensitizes colorectal cancer cells to ixazomib through MCL-1 downregulation and autophagy inhibition.

    Science.gov (United States)

    Yang, Lifeng; Wan, Juefeng; Xiao, Sheng; Barkhouse, Darryll; Zhu, Ji; Li, Guichao; Lu, Bo; Zhang, Zhen

    2016-01-01

    The proteasome inhibitor MLN9708 is an orally administered drug that is hydrolyzed into its active form, MLN2238 (ixazomib). Compared with Bortezomib, MLN2238 has a shorter proteasome dissociation half-life and a lower incidence and severity of peripheral neuropathy, which makes it an attractive candidate for colorectal cancer treatment. In the present study, we observed that MLN2238 induced autophagy, as evidenced by conversion of the autophagosomal marker LC3 from LC3I to LC3II, in colorectal cancer cell lines. Mcl-1, an anti-apoptotic Bcl-2 family protein, was markedly elevated after treating a colorectal cancer cell line with MLN2238. We proved that inhibiting Mcl-1 expression enhances MLN2238 induced apoptosis and negatively regulates autophagy. Co-administration of BH3 mimetic ABT-737 with MLN2238 synergistically kills colorectal cancer cells through MCL-1 neutralization and autophagy inhibition. Furthermore, the synergistic killing effect of the combination therapy is correlated with P53 status in colorectal cancer. These data highlight that the combination of ABT-737 with MLN9708 is a promising therapeutic strategy for human colorectal cancer. PMID:27429848

  18. SIRT3 participates in glucose metabolism interruption and apoptosis induced by BH3 mimetic S1 in ovarian cancer cells.

    Science.gov (United States)

    Xiang, Xi-Yan; Kang, Jin-Song; Yang, Xiao-Chun; Su, Jing; Wu, Yao; Yan, Xiao-Yu; Xue, Ya-Nan; Xu, Ye; Liu, Yu-He; Yu, Chun-Yan; Zhang, Zhi-Chao; Sun, Lian-Kun

    2016-08-01

    The Bcl-2 antiapoptotic proteins are important cancer therapy targets; however, their role in cancer cell metabolism remains unclear. We found that the BH3-only protein mimetic S1, a novel pan Bcl-2 inhibitor, simultaneously interrupted glucose metabolism and induced apoptosis in human SKOV3 ovarian cancer cells, which was related to the activation of SIRT3, a stress-responsive deacetylase. S1 interrupted the cellular glucose metabolism mainly through causing damage to mitochondrial respiration and inhibiting glycolysis. Moreover, S1 upregulated the gene and protein expression of SIRT3, and induced the translocation of SIRT3 from the nucleus to mitochondria. SIRT3 silencing reversed the effects of S1 on glucose metabolism and apoptosis through increasing the level of HK-II localized to the mitochondria, while a combination of the glycolysis inhibitor 2-DG and S1 intensified the cytotoxicity through further upregulation of SIRT3 expression. This study underscores an essential role of SIRT3 in the antitumor effect of Bcl-2 inhibitors in human ovarian cancer through regulating both metabolism and apoptosis. The manipulation of Bcl-2 inhibitors combined with the use of classic glycolysis inhibitors may be rational strategies to improve ovarian cancer therapy. PMID:27277143

  19. Ochre Bathing of the Bearded Vulture: A Bio-Mimetic Model for Early Humans towards Smell Prevention and Health.

    Science.gov (United States)

    Tributsch, Helmut

    2016-01-01

    Since primordial times, vultures have been competing with man for animal carcasses. One of these vultures, the once widespread bearded vulture ( Gypaetus barbatus ), has the habit of bathing its polluted feathers and skin in red iron oxide - ochre - tainted water puddles. Why? Primitive man may have tried to find out and may have discovered its advantages. Red ochre, which has accompanied human rituals and everyday life for more than 100,000 years, is not just a simple red paint for decoration or a symbol for blood. As modern experiments demonstrate, it is active in sunlight producing aggressive chemical species. They can kill viruses and bacteria and convert smelly organic substances into volatile neutral carbon dioxide gas. In this way, ochre can in sunlight sterilize and clean the skin to provide health and comfort and make it scentless, a definitive advantage for nomadic meat hunters. This research thus also demonstrates a sanitary reason for the vulture's habit of bathing in red ochre mud. Prehistoric people have therefore included ochre use into their rituals, especially into those in relation to birth and death. Significant ritual impulses during evolution of man may thus have developed bio-mimetically, inspired from the habits of a vulture. It is discussed how this health strategy could be developed to a modern standard helping to fight antibiotics-resistant bacteria in hospitals. PMID:26784238

  20. Spontaneous Packaging and Hypothermic Storage of Mammalian Cells with a Cell-Membrane-Mimetic Polymer Hydrogel in a Microchip.

    Science.gov (United States)

    Xu, Yan; Mawatari, Kazuma; Konno, Tomohiro; Kitamori, Takehiko; Ishihara, Kazuhiko

    2015-10-21

    Currently, continuous culture/passage and cryopreservation are two major, well-established methods to provide cultivated mammalian cells for experiments in laboratories. Due to the lack of flexibility, however, both laboratory-oriented methods are unable to meet the need for rapidly growing cell-based applications, which require cell supply in a variety of occasions outside of laboratories. Herein, we report spontaneous packaging and hypothermic storage of mammalian cells under refrigerated (4 °C) and ambient conditions (25 °C) using a cell-membrane-mimetic methacryloyloxyethyl phosphorylcholine (MPC) polymer hydrogel incorporated within a glass microchip. Its capability for hypothermic storage of cells was comparatively evaluated over 16 days. The results reveal that the cytocompatible MPC polymer hydrogel, in combination with the microchip structure, enabled hypothermic storage of cells with quite high viability, high intracellular esterase activity, maintained cell membrane integrity, and small morphological change for more than 1 week at 4 °C and at least 4 days at 25 °C. Furthermore, the stored cells could be released from the hydrogel and exhibited the ability to adhere to a surface and achieve confluence under standard cell culture conditions. Both hypothermic storage conditions are ordinary flexible conditions which can be easily established in places outside of laboratories. Therefore, cell packaging and storage using the hydrogel incorporated within the microchip would be a promising miniature and portable solution for flexible supply and delivery of small amounts of cells from bench to bedside.