Hydrogel Design for Supporting Neurite Outgrowth and Promoting Gene Delivery to Maximize Neurite Extension

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Shepard, Jaclyn A.; Stevans, Alyson C.; Holland, Samantha; Wang, Christine E.; Shikanov, Ariella; Shea, Lonnie D.

2012-01-01

Hydrogels capable of gene delivery provide a combinatorial approach for nerve regeneration, with the hydrogel supporting neurite outgrowth and gene delivery inducing the expression of inductive factors. This report investigates the design of hydrogels that balance the requirements for supporting neurite growth with those requirements for promoting gene delivery. Enzymatically-degradable PEG hydrogels encapsulating dorsal root ganglia explants, fibroblasts, and lipoplexes encoding nerve growth factor were gelled within channels that can physically guide neurite outgrowth. Transfection of fibroblasts increased with increasing concentration of Arg-Gly-Asp (RGD) cell adhesion sites and decreasing PEG content. The neurite length increased with increasing RGD concentration within 10% PEG hydrogels, yet was maximal within 7.5% PEG hydrogels at intermediate RGD levels. Delivering lipoplexes within the gel produced longer neurites than culture in NGF-supplemented media or co-culture with cells exposed to DNA prior to encapsulation. Hydrogels designed to support neurite outgrowth and deliver gene therapy vectors locally may ultimately be employed to address multiple barriers that limit regeneration. PMID:22038654

Characterization of BASP1-mediated neurite outgrowth

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Korshunova, Irina; Caroni, Pico; Kolkova, Kateryna

2008-01-01

The brain acid-soluble protein BASP1 (CAP-23, NAP-22) belongs to the family of growth-associated proteins, which also includes GAP-43, a protein recently shown to regulate neural cell adhesion molecule (NCAM)-mediated neurite outgrowth. Here, the effects of BASP1 overexpression were investigated...

NOGO-A induction and localization during chick brain development indicate a role disparate from neurite outgrowth inhibition

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Liwnicz Boleslaw H

2007-04-01

Full Text Available Abstract Background Nogo-A, a myelin-associated protein, inhibits neurite outgrowth and abates regeneration in the adult vertebrate central nervous system (CNS and may play a role in maintaining neural pathways once established. However, the presence of Nogo-A during early CNS development is counterintuitive and hints at an additional role for Nogo-A beyond neurite inhibition. Results We isolated chicken NOGO-A and determined its sequence. A multiple alignment of the amino acid sequence across divergent species, identified five previously undescribed, Nogo-A specific conserved regions that may be relevant for development. NOGO gene transcripts (NOGO-A, NOGO-B and NOGO-C were differentially expressed in the CNS during development and a second NOGO-A splice variant was identified. We further localized NOGO-A expression during key phases of CNS development by in situ hybridization. CNS-associated NOGO-A was induced coincident with neural plate formation and up-regulated by FGF in the transformation of non-neural ectoderm into neural precursors. NOGO-A expression was diffuse in the neuroectoderm during the early proliferative phase of development, and migration, but localized to large projection neurons of the optic tectum and tectal-associated nuclei during architectural differentiation, lamination and network establishment. Conclusion These data suggest Nogo-A plays a functional role in the determination of neural identity and/or differentiation and also appears to play a later role in the networking of large projection neurons during neurite formation and synaptogenesis. These data indicate that Nogo-A is a multifunctional protein with additional roles during CNS development that are disparate from its later role of neurite outgrowth inhibition in the adult CNS.

Non-cytotoxic Concentration of Cisplatin Decreases Neuroplasticity-Related Proteins and Neurite Outgrowth Without Affecting the Expression of NGF in PC12 Cells.

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Ferreira, Rafaela Scalco; Dos Santos, Neife Aparecida Guinaim; Martins, Nádia Maria; Fernandes, Laís Silva; Dos Santos, Antonio Cardozo

2016-11-01

Cisplatin is the most effective and neurotoxic platinum chemotherapeutic agent. It induces a peripheral neuropathy characterized by distal axonal degeneration that might progress to degeneration of cell bodies and apoptosis. Most symptoms occur nearby distal axonal branches and axonal degeneration might induce peripheral neuropathy regardless neuronal apoptosis. The toxic mechanism of cisplatin has been mainly associated with DNA damage, but cisplatin might also affect neurite outgrowth. Nevertheless, the neurotoxic mechanism of cisplatin remains unclear. We investigated the early effects of cisplatin on axonal plasticity by using non-cytotoxic concentrations of cisplatin and PC12 cells as a model of neurite outgrowth and differentiation. PC12 cells express NGF-receptors (trkA) and respond to NGF by forming neurites, branches and synaptic vesicles. For comparison, we used a neuronal model (SH-SY5Y cells) that does not express trkA nor responds to NGF. Cisplatin did not change NGF expression in PC12 cells and decreased neurite outgrowth in both models, suggesting a NGF/trkA independent mechanism. It also reduced axonal growth (GAP-43) and synaptic (synapsin I and synaptophysin) proteins in PC12 cells, without inducing mitochondrial damage or apoptosis. Therefore, cisplatin might affect axonal plasticity before DNA damage, NGF/trkA down-regulation, mitochondrial damage or neuronal apoptosis. This is the first study to show that neuroplasticity-related proteins might be early targets of the neurotoxic action of cisplatin and their role on cisplatin-induced peripheral neuropathy should be investigated in vivo.

Chronic, low-dose rotenone reproduces Lewy neurites found in early stages of Parkinson's disease, reduces mitochondrial movement and slowly kills differentiated SH-SY5Y neural cells

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Liu Lei

2008-12-01

Full Text Available Abstract Background Parkinson's disease, the most common adult neurodegenerative movement disorder, demonstrates a brain-wide pathology that begins pre-clinically with alpha-synuclein aggregates ("Lewy neurites" in processes of gut enteric and vagal motor neurons. Rostral progression into substantia nigra with death of dopamine neurons produces the motor impairment phenotype that yields a clinical diagnosis. The vast majority of Parkinson's disease occurs sporadically, and current models of sporadic Parkinson's disease (sPD can utilize directly infused or systemic neurotoxins. Results We developed a differentiation protocol for human SH-SY5Y neuroblastoma that yielded non-dividing dopaminergic neural cells with long processes that we then exposed to 50 nM rotenone, a complex I inhibitor used in Parkinson's disease models. After 21 days of rotenone, ~60% of cells died. Their processes retracted and accumulated ASYN-(+ and UB-(+ aggregates that blocked organelle transport. Mitochondrial movement velocities were reduced by 8 days of rotenone and continued to decline over time. No cytoplasmic inclusions resembling Lewy bodies were observed. Gene microarray analyses showed that the majority of genes were under-expressed. qPCR analyses of 11 mtDNA-encoded and 10 nDNA-encoded mitochondrial electron transport chain RNAs' relative expressions revealed small increases in mtDNA-encoded genes and lesser regulation of nDNA-encoded ETC genes. Conclusion Subacute rotenone treatment of differentiated SH-SY5Y neuroblastoma cells causes process retraction and partial death over several weeks, slowed mitochondrial movement in processes and appears to reproduce the Lewy neuritic changes of early Parkinson's disease pathology but does not cause Lewy body inclusions. The overall pattern of transcriptional regulation is gene under-expression with minimal regulation of ETC genes in spite of rotenone's being a complex I toxin. This rotenone-SH-SY5Y model in a

Signaling mechanisms of neurite outgrowth induced by the cell adhesion molecules NCAM and N-cadherin

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Hansen, S M; Berezin, V; Bock, E

2008-01-01

Formation of appropriate neural circuits depends on a complex interplay between extracellular guiding cues and intracellular signaling events that result in alterations of cytoskeletal dynamics and a neurite growth response. Surface-expressed cell adhesion molecules (CAMs) interact with the surro......Formation of appropriate neural circuits depends on a complex interplay between extracellular guiding cues and intracellular signaling events that result in alterations of cytoskeletal dynamics and a neurite growth response. Surface-expressed cell adhesion molecules (CAMs) interact...... extracellular guidance cues to intracellular events and thereby regulating neurite outgrowth. In this review, we focus on two CAMs, the neural cell adhesion molecule (NCAM) and N-cadherin, and their ability to mediate signaling associated with a neurite outgrowth response. In particular, we will focus on direct...

Cocaine- and amphetamine-regulated transcript facilitates the neurite outgrowth in cortical neurons after oxygen and glucose deprivation through PTN-dependent pathway.

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Wang, Y; Qiu, B; Liu, J; Zhu, Wei-Guo; Zhu, S

2014-09-26

Cocaine- and amphetamine-regulated transcript (CART) is a neuropeptide that plays neuroprotective roles in cerebral ischemia and reperfusion (I/R) injury in animal models or oxygen and glucose deprivation (OGD) in cultured neurons. Recent data suggest that intranasal CART treatment facilitates neuroregeneration in stroke brain. However, little is known about the effects of post-treatment with CART during the neuronal recovery after OGD and reoxygenation in cultured primary cortical neurons. The present study was to investigate the role of CART treated after OGD injury in neurons. Primary mouse cortical neurons were subjected to OGD and then treated with CART. Our data show that post-treatment with CART reduced the neuronal apoptosis caused by OGD injury. In addition, CART repaired OGD-impaired cortical neurons by increasing the expression of growth-associated protein 43 (GAP43), which promotes neurite outgrowth. This effect depends on pleiotrophin (PTN) as siRNA-mediated PTN knockdown totally abolished the increase in CART-stimulated GAP43 protein levels. In summary, our findings demonstrate that CART repairs the neuronal injury after OGD by facilitating neurite outgrowth through PTN-dependent pathway. The role for CART in neurite outgrowth makes it a new potential therapeutic agent for the treatment of neurodegenerative diseases. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Stimulation of neuronal neurite outgrowth using functionalized carbon nanotubes

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Matsumoto, K; Sato, C; Shimizu, N [Graduate School of Life Sciences, Toyo University, 1-1-1 Izumino, Itakura-machi, Ora-gun, Gunma 374-0193 (Japan); Naka, Y [Bio-Nano Electronics Research Center, Toyo University, 2100 Kujirai, Kawagoe-shi, Saitama 350-8585 (Japan); Whitby, R, E-mail: shimizu@toyonet.toyo.ac.jp [School of Pharmacy and Biomolecular Sciences, University of Brighton, Cockroft Building, Lewes Road, Brighton BN2 4GJ (United Kingdom)

2010-03-19

Low concentrations (0.11-1.7 {mu}g ml{sup -1}) of functionalized carbon nanotubes (CNTs), which are multi-walled CNTs modified by amino groups, when added with nerve growth factor (NGF), promoted outgrowth of neuronal neurites in dorsal root ganglion (DRG) neurons and rat pheochromocytoma cell line PC12h cells in culture media. The quantity of active extracellular signal-regulated kinase (ERK) was higher after the addition of both 0.85 {mu}g ml{sup -1} CNTs and NGF than that with NGF alone. CNTs increased the number of cells with neurite outgrowth in DRG neurons and PC12h cells after the inhibition of the ERK signaling pathway using a mitogen-activated protein kinase (MAPK)/ERK kinase (MEK) inhibitor. Active ERK proteins were detected in MEK inhibitor-treated neurons after the addition of CNTs to the culture medium. These results demonstrate that CNTs may stimulate neurite outgrowth by activation of the ERK signaling pathway. Thus, CNTs are biocompatible and are promising candidates for biological applications and devices.

Deficits in Neurite Density Underlie White Matter Structure Abnormalities in First-Episode Psychosis.

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Rae, Charlotte L; Davies, Geoff; Garfinkel, Sarah N; Gabel, Matt C; Dowell, Nicholas G; Cercignani, Mara; Seth, Anil K; Greenwood, Kathryn E; Medford, Nick; Critchley, Hugo D

2017-11-15

Structural abnormalities across multiple white matter tracts are recognized in people with early psychosis, consistent with dysconnectivity as a neuropathological account of symptom expression. We applied advanced neuroimaging techniques to characterize microstructural white matter abnormalities for a deeper understanding of the developmental etiology of psychosis. Thirty-five first-episode psychosis patients, and 19 healthy controls, participated in a quantitative neuroimaging study using neurite orientation dispersion and density imaging, a multishell diffusion-weighted magnetic resonance imaging technique that distinguishes white matter fiber arrangement and geometry from changes in neurite density. Fractional anisotropy (FA) and mean diffusivity images were also derived. Tract-based spatial statistics compared white matter structure between patients and control subjects and tested associations with age, symptom severity, and medication. Patients with first-episode psychosis had lower regional FA in multiple commissural, corticospinal, and association tracts. These abnormalities predominantly colocalized with regions of reduced neurite density, rather than aberrant fiber bundle arrangement (orientation dispersion index). There was no direct relationship with active symptoms. FA decreased and orientation dispersion index increased with age in patients, but not control subjects, suggesting accelerated effects of white matter geometry change. Deficits in neurite density appear fundamental to abnormalities in white matter integrity in early psychosis. In the first application of neurite orientation dispersion and density imaging in psychosis, we found that processes compromising axonal fiber number, density, and myelination, rather than processes leading to spatial disruption of fiber organization, are implicated in the etiology of psychosis. This accords with a neurodevelopmental origin of aberrant brain-wide structural connectivity predisposing individuals to

Neurite, a finite difference large scale parallel program for the simulation of electrical signal propagation in neurites under mechanical loading.

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Julián A García-Grajales

Full Text Available With the growing body of research on traumatic brain injury and spinal cord injury, computational neuroscience has recently focused its modeling efforts on neuronal functional deficits following mechanical loading. However, in most of these efforts, cell damage is generally only characterized by purely mechanistic criteria, functions of quantities such as stress, strain or their corresponding rates. The modeling of functional deficits in neurites as a consequence of macroscopic mechanical insults has been rarely explored. In particular, a quantitative mechanically based model of electrophysiological impairment in neuronal cells, Neurite, has only very recently been proposed. In this paper, we present the implementation details of this model: a finite difference parallel program for simulating electrical signal propagation along neurites under mechanical loading. Following the application of a macroscopic strain at a given strain rate produced by a mechanical insult, Neurite is able to simulate the resulting neuronal electrical signal propagation, and thus the corresponding functional deficits. The simulation of the coupled mechanical and electrophysiological behaviors requires computational expensive calculations that increase in complexity as the network of the simulated cells grows. The solvers implemented in Neurite--explicit and implicit--were therefore parallelized using graphics processing units in order to reduce the burden of the simulation costs of large scale scenarios. Cable Theory and Hodgkin-Huxley models were implemented to account for the electrophysiological passive and active regions of a neurite, respectively, whereas a coupled mechanical model accounting for the neurite mechanical behavior within its surrounding medium was adopted as a link between electrophysiology and mechanics. This paper provides the details of the parallel implementation of Neurite, along with three different application examples: a long myelinated axon

cAMP-induced activation of protein kinase A and p190B RhoGAP mediates down-regulation of TC10 activity at the plasma membrane and neurite outgrowth.

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Koinuma, Shingo; Takeuchi, Kohei; Wada, Naoyuki; Nakamura, Takeshi

2017-11-01

Cyclic AMP plays a pivotal role in neurite growth. During outgrowth, a trafficking system supplies membrane at growth cones. However, the cAMP-induced signaling leading to the regulation of membrane trafficking remains unknown. TC10 is a Rho family GTPase that is essential for specific types of vesicular trafficking. Recent studies have shown a role of TC10 in neurite growth in NGF-treated PC12 cells. Here, we investigated a mechanical linkage between cAMP and TC10 in neuritogenesis. Plasmalemmal TC10 activity decreased abruptly after cAMP addition in neuronal cells. TC10 was locally inactivated at extending neurite tips in cAMP-treated PC12 cells. TC10 depletion led to a decrease in cAMP-induced neurite outgrowth. Constitutively active TC10 could not rescue this growth reduction, supporting our model for a role of GTP hydrolysis of TC10 in neuritogenesis by accelerating vesicle fusion. The cAMP-induced TC10 inactivation was mediated by PKA. Considering cAMP-induced RhoA inactivation, we found that p190B, but not p190A, mediated inactivation of TC10 and RhoA. Upon cAMP treatment, p190B was recruited to the plasma membrane. STEF depletion and Rac1-N17 expression reduced cAMP-induced TC10 inactivation. Together, the PKA-STEF-Rac1-p190B pathway leading to inactivation of TC10 and RhoA at the plasma membrane plays an important role in cAMP-induced neurite outgrowth. © 2017 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

The functionalized amino acid (S-Lacosamide subverts CRMP2-mediated tubulin polymerization to prevent constitutive and activity-dependent increase in neurite outgrowth

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Sarah M Wilson

2014-07-01

Full Text Available Activity-dependent neurite outgrowth is a highly complex, regulated process with important implications for neuronal circuit remodeling in development as well as in seizure-induced sprouting in epilepsy. Recent work has linked outgrowth to collapsin response mediator protein 2 (CRMP2, an intracellular phosphoprotein originally identified as axon guidance and growth cone collapse protein. The neurite outgrowth promoting function of CRMP2 is regulated by its phosphorylation state. In this study, depolarization (potassium chloride-driven activity increased the level of active CRMP2 by decreasing its phosphorylation by GSK3β via a reduction in priming by Cdk5. To determine the contribution of CRMP2 in activity-driven neurite outgrowth, we screened a limited set of compounds for their ability to reduce neurite outgrowth but not modify voltage-gated sodium channel (VGSC biophysical properties. This led to the identification of (S-lacosamide ((S-LCM, a stereoisomer of the clinically used antiepileptic drug (R-LCM (Vimpat®, as a novel tool for preferentially targeting CRMP2-mediated neurite outgrowth. Whereas (S-LCM was ineffective in targeting VGSCs, the presumptive pharmacological targets of (R-LCM, (S-LCM was more efficient than (R-LCM in subverting neurite outgrowth. Biomolecular interaction analyses revealed that (S-LCM bound to wildtype CRMP2 with low micromolar affinity, similar to (R-LCM. Through the use of this novel tool, the activity-dependent increase in neurite outgrowth observed following depolarization was characterized to be reliant on CRMP2 function. Knockdown of CRMP2 by siRNA in cortical neurons resulted in reduced CRMP2-dependent neurite outgrowth; incubation with (S-LCM phenocopied this effect. Other CRMP2-mediated processes were unaffected. (S-LCM subverted neurite outgrowth not by affecting the canonical CRMP2-tubulin association but rather by impairing the ability of CRMP2 to promote tubulin polymerization, events that are

Morphological identification and development of neurite in Drosophila ventral nerve cord neuropil.

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Gan, Guangming; Lv, Huihui; Xie, Wei

2014-01-01

In Drosophila, ventral nerve cord (VNC) occupies most of the larval central nervous system (CNS). However, there is little literature elaborating upon the specific types and growth of neurites as defined by their structural appearance in Drosophila larval VNC neuropil. Here we report the ultrastructural development of different types VNC neurites in ten selected time points in embryonic and larval stages utilizing transmission electron microscopy. There are four types of axonal neurites as classified by the type of vesicular content: clear vesicle (CV) neurites have clear vesicles and some T-bar structures; Dense-core vesicle (DV) neurites have dense-core vesicles and without T-bar structures; Mixed vesicle (MV) neurites have mixed vesicles and some T-bar structures; Large vesicle (LV) neurites are dominated by large, translucent spherical vesicles but rarely display T-bar structures. We found dramatic remodeling in CV neurites which can be divided into five developmental phases. The neurite is vacuolated in primary (P) phase, they have mitochondria, microtubules or big dark vesicles in the second (S) phase, and they contain immature synaptic features in the third (T) phase. The subsequent bifurcate (B) phase appears to undergo major remodeling with the appearance of the bifurcation or dendritic growth. In the final mature (M) phase, high density of commensurate synaptic vesicles are distributed around T-bar structures. There are four kinds of morphological elaboration of the CVI neurite sub-types. First, new neurite produces at the end of axon. Second, new neurite bubbles along the axon. Third, the preexisting neurite buds and develops into several neurites. The last, the bundled axons form irregularly shape neurites. Most CVI neurites in M phase have about 1.5-3 µm diameter, they could be suitable to analyze their morphology and subcellular localization of specific proteins by light microscopy, and they could serve as a potential model in CNS in vivo development.

Electric field-induced astrocyte alignment directs neurite outgrowth.

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Alexander, John K; Fuss, Babette; Colello, Raymond J

2006-05-01

The extension and directionality of neurite outgrowth are key to achieving successful target connections during both CNS development and during the re-establishment of connections lost after neural trauma. The degree of axonal elongation depends, in large part, on the spatial arrangement of astrocytic processes rich in growth-promoting proteins. Because astrocytes in culture align their processes on exposure to an electrical field of physiological strength, we sought to determine the extent to which aligned astrocytes affect neurite outgrowth. To this end, dorsal root ganglia cells were seeded onto cultured rat astrocytes that were pre-aligned by exposure to an electric field of physiological strength (500 mV mm(-1)). Using confocal microscopy and digital image analysis, we found that neurite outgrowth at 24 hours and at 48 hours is enhanced significantly and directed consistently along the aligned astrocyte processes. Moreover, this directed neurite outgrowth is maintained when grown on fixed, aligned astrocytes. Collectively, these results indicate that endogenous electric fields present within the developing CNS might act to align astrocyte processes, which can promote and direct neurite growth. Furthermore, these results demonstrate a simple method to produce an aligned cellular substrate, which might be used to direct regenerating neurites.

Neurotrophin Promotes Neurite Outgrowth by Inhibiting Rif GTPase Activation Downstream of MAPKs and PI3K Signaling.

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Tian, Xiaoxia; Yan, Huijuan; Li, Jiayi; Wu, Shuang; Wang, Junyu; Fan, Lifei

2017-01-13

Members of the well-known semaphorin family of proteins can induce both repulsive and attractive signaling in neural network formation and their cytoskeletal effects are mediated in part by small guanosine 5'-triphosphatase (GTPases). The aim of this study was to investigate the cellular role of Rif GTPase in the neurotrophin-induced neurite outgrowth. By using PC12 cells which are known to cease dividing and begin to show neurite outgrowth responding to nerve growth factor (NGF), we found that semaphorin 6A was as effective as nerve growth factor at stimulating neurite outgrowth in PC12 cells, and that its neurotrophic effect was transmitted through signaling by mitogen-activated protein kinases (MAPKs) and phosphatidylinositol-3-kinase (PI3K). We further found that neurotrophin-induced neurite formation in PC12 cells could be partially mediated by inhibition of Rif GTPase activity downstream of MAPKs and PI3K signaling. In conclusion, we newly identified Rif as a regulator of the cytoskeletal rearrangement mediated by semaphorins.

Morphological identification and development of neurite in Drosophila ventral nerve cord neuropil.

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Guangming Gan

Full Text Available In Drosophila, ventral nerve cord (VNC occupies most of the larval central nervous system (CNS. However, there is little literature elaborating upon the specific types and growth of neurites as defined by their structural appearance in Drosophila larval VNC neuropil. Here we report the ultrastructural development of different types VNC neurites in ten selected time points in embryonic and larval stages utilizing transmission electron microscopy. There are four types of axonal neurites as classified by the type of vesicular content: clear vesicle (CV neurites have clear vesicles and some T-bar structures; Dense-core vesicle (DV neurites have dense-core vesicles and without T-bar structures; Mixed vesicle (MV neurites have mixed vesicles and some T-bar structures; Large vesicle (LV neurites are dominated by large, translucent spherical vesicles but rarely display T-bar structures. We found dramatic remodeling in CV neurites which can be divided into five developmental phases. The neurite is vacuolated in primary (P phase, they have mitochondria, microtubules or big dark vesicles in the second (S phase, and they contain immature synaptic features in the third (T phase. The subsequent bifurcate (B phase appears to undergo major remodeling with the appearance of the bifurcation or dendritic growth. In the final mature (M phase, high density of commensurate synaptic vesicles are distributed around T-bar structures. There are four kinds of morphological elaboration of the CVI neurite sub-types. First, new neurite produces at the end of axon. Second, new neurite bubbles along the axon. Third, the preexisting neurite buds and develops into several neurites. The last, the bundled axons form irregularly shape neurites. Most CVI neurites in M phase have about 1.5-3 µm diameter, they could be suitable to analyze their morphology and subcellular localization of specific proteins by light microscopy, and they could serve as a potential model in CNS in vivo

DA-9801 promotes neurite outgrowth via ERK1/2-CREB pathway in PC12 cells.

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Won, Jong Hoon; Ahn, Kyong Hoon; Back, Moon Jung; Ha, Hae Chan; Jang, Ji Min; Kim, Ha Hyung; Choi, Sang-Zin; Son, Miwon; Kim, Dae Kyong

2015-01-01

In the present study, we examined the mechanisms underlying the effect of DA-9801 on neurite outgrowth. We found that DA-9801 elicits its effects via the mitogen-activated protein kinase (MEK) extracellular signal-regulated kinase (ERK)1/2-cAMP response element-binding protein (CREB) pathway. DA-9801, an extract from a mixture of Dioscorea japonica and Dioscorea nipponica, was reported to promote neurite outgrowth in PC12 cells. The effects of DA-9801 on cell viability and expression of neuronal markers were evaluated in PC12 cells. To investigate DA-9801 action, specific inhibitors targeting the ERK signaling cascade were used. No cytotoxicity was observed in PC12 cells at DA-9801 concentrations of less than 30 µg/mL. In the presence of nerve growth factor (NGF, 2 ng/mL), DA-9801 promoted neurite outgrowth and increased the relative mRNA levels of neurofilament-L (NF-L), a marker of neuronal differentiation. The Raf-1 inhibitor GW5074 and MEK inhibitor PD98059 significantly attenuated DA-9801-induced neurite outgrowth. Additionally, the MEK1 and MEK2 inhibitor SL327 significantly attenuated the increase in the percentage of neurite-bearing PC12 cells induced by DA-9801 treatment. Conversely, the selective p38 mitogen-activated protein kinase inhibitor SB203580 did not attenuate the DA-9801 treatment-induced increase in the percentage of neurite-bearing PC12 cells. DA-9801 enhanced the phosphorylation of ERK1/2 and CREB in PC12 cells incubated with and without NGF. Pretreatment with PD98059 blocked the DA-9801-induced phosphorylation of ERK1/2 and CREB. In conclusion, DA-9801 induces neurite outgrowth by affecting the ERK1/2-CREB signaling pathway. Insights into the mechanism underlying this effect of DA-9801 may suggest novel potential strategies for the treatment of peripheral neuropathy.

DNA topoisomerase IIβ stimulates neurite outgrowth in neural differentiated human mesenchymal stem cells through regulation of Rho-GTPases (RhoA/Rock2 pathway) and Nurr1 expression.

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Zaim, Merve; Isik, Sevim

2018-04-25

DNA topoisomerase IIβ (topo IIβ) is known to regulate neural differentiation by inducing the neuronal genes responsible for critical neural differentiation events such as neurite outgrowth and axon guidance. However, the pathways of axon growth controlled by topo IIβ have not been clarified yet. Microarray results of our previous study have shown that topo IIβ silencing in neural differentiated primary human mesenchymal stem cells (hMSCs) significantly alters the expression pattern of genes involved in neural polarity, axonal growth, and guidance, including Rho-GTPases. This study aims to further analyze the regulatory role of topo IIβ on the process of axon growth via regulation of Rho-GTPases. For this purpose, topo IIβ was silenced in neurally differentiated hMSCs. Cells lost their morphology because of topo IIβ deficiency, becoming enlarged and flattened. Additionally, a reduction in both neural differentiation efficiency and neurite length, upregulation in RhoA and Rock2, downregulation in Cdc42 gene expression were detected. On the other hand, cells were transfected with topo IIβ gene to elucidate the possible neuroprotective effect of topo IIβ overexpression on neural-induced hMSCs. Topo IIβ overexpression prompted all the cells to exhibit neural cell morphology as characterized by longer neurites. RhoA and Rock2 expressions were downregulated, whereas Cdc42 expression was upregulated. Nurr1 expression level correlated with topo IIβ in both topo IIβ-overexpressed and -silenced cells. Furthermore, differential translocation of Rho-GTPases was detected by immunostaining in response to topo IIβ. Our results suggest that topo IIβ deficiency could give rise to neurodegeneration through dysregulation of Rho-GTPases. However, further in-vivo research is needed to demonstrate if re-regulation of Rho GTPases by topo IIβ overexpression could be a neuroprotective treatment in the case of neurodegenerative diseases.

New function of the adaptor protein SH2B1 in brain-derived neurotrophic factor-induced neurite outgrowth.

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Chien-Hung Shih

Full Text Available Neurite outgrowth is an essential process for the establishment of the nervous system. Brain-derived neurotrophic factor (BDNF binds to its receptor TrkB and regulates axonal and dendritic morphology of neurons through signal transduction and gene expression. SH2B1 is a signaling adaptor protein that regulates cellular signaling in various physiological processes. The purpose of this study is to investigate the role of SH2B1 in the development of the central nervous system. In this study, we show that knocking down SH2B1 reduces neurite formation of cortical neurons whereas overexpression of SH2B1β promotes the development of hippocampal neurons. We further demonstrate that SH2B1β promotes BDNF-induced neurite outgrowth and signaling using the established PC12 cells stably expressing TrkB, SH2B1β or SH2B1β mutants. Our data indicate that overexpressing SH2B1β enhances BDNF-induced MEK-ERK1/2, and PI3K-AKT signaling pathways. Inhibition of MEK-ERK1/2 and PI3K-AKT pathways by specific inhibitors suggest that these two pathways are required for SH2B1β-promoted BDNF-induced neurite outgrowth. Moreover, SH2B1β enhances BDNF-stimulated phosphorylation of signal transducer and activator of transcription 3 at serine 727. Finally, our data indicate that the SH2 domain and tyrosine phosphorylation of SH2B1β contribute to BDNF-induced signaling pathways and neurite outgrowth. Taken together, these findings demonstrate that SH2B1β promotes BDNF-induced neurite outgrowth through enhancing pathways involved MEK-ERK1/2 and PI3K-AKT.

The protection of acetylcholinesterase inhibitor on β-amyloid-induced injury of neurite outgrowth via regulating axon guidance related genes expression in neuronal cells

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Shen, Jiao-Ning; Wang, Deng-Shun; Wang, Rui

2012-01-01

Cognitive deficits in AD correlate with progressive synaptic dysfunction and loss. The Rho family of small GTPases, including Rho, Rac, and Cdc42, has a central role in cellular motility and cytokinesis. Acetylcholinesterase inhibitor has been found to protect cells against a broad range of reagents-induced injuries. Present studies examined if the effect of HupA on neurite outgrowth in Aβ-treated neuronal cells executed via regulating Rho-GTPase mediated axon guidance relative gene expressio...

β-Hydroxy-β-Methylbutyrate (HMB) Promotes Neurite Outgrowth in Neuro2a Cells.

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Salto, Rafael; Vílchez, Jose D; Girón, María D; Cabrera, Elena; Campos, Nefertiti; Manzano, Manuel; Rueda, Ricardo; López-Pedrosa, Jose M

2015-01-01

β-Hydroxy-β-methylbutyrate (HMB) has been shown to enhance cell survival, differentiation and protein turnover in muscle, mainly activating phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) and mitogen-activated protein kinases/ extracellular-signal-regulated kinases (MAPK/ERK) signaling pathways. Since these two pathways are related to neuronal survival and differentiation, in this study, we have investigated the neurotrophic effects of HMB in mouse neuroblastoma Neuro2a cells. In Neuro2a cells, HMB promotes differentiation to neurites independent from any effects on proliferation. These effects are mediated by activation of both the PI3K/Akt and the extracellular-signal-regulated kinases (ERK1/2) signaling as demonstrated by the use of specific inhibitors of these two pathways. As myocyte-enhancer factor 2 (MEF2) family of transcription factors are involved in neuronal survival and plasticity, the transcriptional activity and protein levels of MEF2 were also evaluated. HMB promoted MEF2-dependent transcriptional activity mediated by the activation of Akt and ERK1/2 pathways. Furthermore, HMB increases the expression of brain glucose transporters 1 (GLUT1) and 3 (GLUT3), and mTOR phosphorylation, which translates in a higher protein synthesis in Neuro2a cells. Furthermore, Torin1 and rapamycin effects on MEF2 transcriptional activity and HMB-dependent neurite outgrowth support that HMB acts through mTORC2. Together, these findings provide clear evidence to support an important role of HMB in neurite outgrowth.

Comparison of neurite density measured by MRI and histology after TBI.

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Shiyang Wang

Full Text Available Functional recovery after brain injury in animals is improved by marrow stromal cells (MSC which stimulate neurite reorganization. However, MRI measurement of neurite density changes after injury has not been performed. In this study, we investigate the feasibility of MRI measurement of neurite density in an animal model of traumatic brain injury (TBI with and without MSC treatment.Fifteen male Wistar rats, were treated with saline (n = 6 or MSCs (n = 9 and were sacrificed at 6 weeks after controlled cortical impact (CCI. Healthy non-CCI rats (n = 5, were also employed. Ex-vivo MRI scans were performed two days after the rats were sacrificed. Multiple-shell hybrid diffusion imaging encoding scheme and spherical harmonic expansion of a two-compartment water diffusion displacement model were used to extract neurite related parameters. Bielshowski and Luxol Fast blue was used for staining axons and myelin, respectively. Modified Morris water maze and neurological severity score (mNSS test were performed for functional evaluation. The treatment effects, the correlations between neurite densities measured by MRI and histology, and the correlations between MRI and functional variables were calculated by repeated measures analysis of variance, the regression correlation analysis tests, and spearman correlation coefficients.Neurite densities exhibited a significant correlation (R(2>0.80, p<1E-20 between MRI and immuno-histochemistry measurements with 95% lower bound of the intra-correlation coefficient (ICC as 0.86. The conventional fractional anisotropy (FA correlated moderately with histological neurite density (R(2 = 0.59, P<1E-5 with 95% lower bound of ICC as 0.76. MRI data revealed increased neurite reorganization with MSC treatment compared with saline treatment, confirmed by histological data from the same animals. mNSS were significantly correlated with MRI neurite density in the hippocampus region.The present studies

MiR-130a regulates neurite outgrowth and dendritic spine density by targeting MeCP2

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Yunjia Zhang

2016-06-01

Full Text Available ABSTRACT MicroRNAs (miRNAs are critical for both development and function of the central nervous system. Significant evidence suggests that abnormal expression of miRNAs is associated with neurodevelopmental disorders. MeCP2 protein is an epigenetic regulator repressing or activating gene transcription by binding to methylated DNA. Both loss-of-function and gain-of-function mutations in the MECP2 gene lead to neurodevelopmental disorders such as Rett syndrome, autism and MECP2 duplication syndrome. In this study, we demonstrate that miR-130a inhibits neurite outgrowth and reduces dendritic spine density as well as dendritic complexity. Bioinformatics analyses, cell cultures and biochemical experiments indicate that miR-130a targets MECP2 and down-regulates MeCP2 protein expression. Furthermore, expression of the wild-type MeCP2, but not a loss-of-function mutant, rescues the miR-130a-induced phenotype. Our study uncovers the MECP2 gene as a previous unknown target for miR-130a, supporting that miR-130a may play a role in neurodevelopment by regulating MeCP2. Together with data from other groups, our work suggests that a feedback regulatory mechanism involving both miR-130a and MeCP2 may serve to ensure their appropriate expression and function in neural development.

Mechanosensitivity of Embryonic Neurites Promotes Their Directional Extension and Schwann Cells Progenitors Migration

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Gonzalo Rosso

2017-11-01

Full Text Available Background/Aims: Migration of Schwann cells (SCs progenitors and neurite outgrowth from embryonic dorsal root ganglions (DRGs are two central events during the development of the peripheral nervous system (PNS. How these two enthralling events preceding myelination are promoted is of great relevance from basic research and clinical aspects alike. Recent evidence demonstrates that biophysical cues (extracellular matrix stiffness and biochemical signaling act in concert to regulate PNS myelination. Microenvironment stiffness of SCs progenitors and embryonic neurites dynamically changes during development. Methods: DRG explants were isolated from day 12.5 to 13.5 mice embryos and plated on laminin-coated substrates with varied stiffness values. After 4 days in culture and immunostaining with specific markers, neurite outgrowth pattern, SCs progenitors migration, and growth cone shape and advance were analyzed with confocal fluorescence microscopy. Results: We found out that growing substrate stiffness promotes directional neurite outgrowth, SCs progenitors migration, growth cone advance and presumably axons fasciculation. Conclusions: DRG explants are in vitro models for the research of PNS development, myelination and regeneration. Consequently, we conclude the following: Our observations point out the importance of mechanosensitivity for the PNS. At the same time, they prompt the investigation of the important yet unclear links between PNS biomechanics and inherited neuropathies with myelination disorders such as Charcot-Marie-Tooth 1A and hereditary neuropathy with liability to pressure palsies. Finally, they encourage the consideration of mechanosensitivity in bioengineering of scaffolds to aid nerve regeneration after injury.

Neto2 Assembles with Kainate Receptors in DRG Neurons during Development and Modulates Neurite Outgrowth in Adult Sensory Neurons.

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Vernon, Claire G; Swanson, Geoffrey T

2017-03-22

Peripheral sensory neurons in the dorsal root ganglia (DRG) are the initial transducers of sensory stimuli, including painful stimuli, from the periphery to central sensory and pain-processing centers. Small- to medium-diameter non-peptidergic neurons in the neonatal DRG express functional kainate receptors (KARs), one of three subfamilies of ionotropic glutamate receptors, as well as the putative KAR auxiliary subunit Neuropilin- and tolloid-like 2 (Neto2). Neto2 alters recombinant KAR function markedly but has yet to be confirmed as an auxiliary subunit that assembles with and alters the function of endogenous KARs. KARs in neonatal DRG require the GluK1 subunit as a necessary constituent, but it is unclear to what extent other KAR subunits contribute to the function and proposed roles of KARs in sensory ganglia, which include promotion of neurite outgrowth and modulation of glutamate release at the DRG-dorsal horn synapse. In addition, KARs containing the GluK1 subunit are implicated in modes of persistent but not acute pain signaling. We show here that the Neto2 protein is highly expressed in neonatal DRG and modifies KAR gating in DRG neurons in a developmentally regulated fashion in mice. Although normally at very low levels in adult DRG neurons, Neto2 protein expression can be upregulated via MEK/ERK signaling and after sciatic nerve crush and Neto2 -/- neurons from adult mice have stunted neurite outgrowth. These data confirm that Neto2 is a bona fide KAR auxiliary subunit that is an important constituent of KARs early in sensory neuron development and suggest that Neto2 assembly is critical to KAR modulation of DRG neuron process outgrowth. SIGNIFICANCE STATEMENT Pain-transducing peripheral sensory neurons of the dorsal root ganglia (DRG) express kainate receptors (KARs), a subfamily of glutamate receptors that modulate neurite outgrowth and regulate glutamate release at the DRG-dorsal horn synapse. The putative KAR auxiliary subunit Neuropilin- and

Chemoenzymatically prepared konjac ceramide inhibits NGF-induced neurite outgrowth by a semaphorin 3A-like action

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Seigo Usuki

2016-03-01

Full Text Available Dietary sphingolipids such as glucosylceramide (GlcCer are potential nutritional factors associated with prevention of metabolic syndrome. Our current understanding is that dietary GlcCer is degraded to ceramide and further metabolized to sphingoid bases in the intestine. However, ceramide is only found in trace amounts in food plants and thus is frequently taken as GlcCer in a health supplement. In the present study, we successfully prepared konjac ceramide (kCer using endoglycoceramidase I (EGCase I. Konjac, a plant tuber, is an enriched source of GlcCer (kGlcCer, and has been commercialized as a dietary supplement to improve dry skin and itching that are caused by a deficiency of epidermal ceramide. Nerve growth factor (NGF produced by skin cells is one of the itch factors in the stratum corneum of the skin. Semaphorin 3A (Sema 3A has been known to inhibit NGF-induced neurite outgrowth of epidermal nerve fibers. It is well known that the itch sensation is regulated by the balance between NGF and Sema 3A. In the present study, while kGlcCer did not show an in vitro inhibitory effect on NGF-induced neurite outgrowth of PC12 cells, kCer was demonstrated to inhibit a remarkable neurite outgrowth. In addition, the effect of kCer was similar to that of Sema 3A in cell morphological changes and neurite retractions, but different from C2-Ceramide. kCer showed a Sema 3A-like action, causing CRMP2 phosphorylation, which results in a collapse of neurite growth cones. Thus, it is expected that kCer is an advanced konjac ceramide material that may have neurite outgrowth-specific action to relieve uncontrolled and serious itching, in particular, from atopic eczema.

Comparative sensitivity of human and rat neural cultures to chemical-induced inhibition of neurite outgrowth

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Harrill, Joshua A.; Freudenrich, Theresa M.; Robinette, Brian L.; Mundy, William R., E-mail: mundy.william@epa.gov

2011-11-15

There is a need for rapid, efficient and cost-effective alternatives to traditional in vivo developmental neurotoxicity testing. In vitro cell culture models can recapitulate many of the key cellular processes of nervous system development, including neurite outgrowth, and may be used as screening tools to identify potential developmental neurotoxicants. The present study compared primary rat cortical cultures and human embryonic stem cell-derived neural cultures in terms of: 1) reproducibility of high content image analysis based neurite outgrowth measurements, 2) dynamic range of neurite outgrowth measurements and 3) sensitivity to chemicals which have been shown to inhibit neurite outgrowth. There was a large increase in neurite outgrowth between 2 and 24 h in both rat and human cultures. Image analysis data collected across multiple cultures demonstrated that neurite outgrowth measurements in rat cortical cultures were more reproducible and had higher dynamic range as compared to human neural cultures. Human neural cultures were more sensitive than rat cortical cultures to chemicals previously shown to inhibit neurite outgrowth. Parallel analysis of morphological (neurite count, neurite length) and cytotoxicity (neurons per field) measurements were used to detect selective effects on neurite outgrowth. All chemicals which inhibited neurite outgrowth in rat cortical cultures did so at concentrations which did not concurrently affect the number of neurons per field, indicating selective effects on neurite outgrowth. In contrast, more than half the chemicals which inhibited neurite outgrowth in human neural cultures did so at concentrations which concurrently decreased the number of neurons per field, indicating that effects on neurite outgrowth were secondary to cytotoxicity. Overall, these data demonstrate that the culture models performed differently in terms of reproducibility, dynamic range and sensitivity to neurite outgrowth inhibitors. While human neural

Comparative sensitivity of human and rat neural cultures to chemical-induced inhibition of neurite outgrowth

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Harrill, Joshua A.; Freudenrich, Theresa M.; Robinette, Brian L.; Mundy, William R.

2011-01-01

There is a need for rapid, efficient and cost-effective alternatives to traditional in vivo developmental neurotoxicity testing. In vitro cell culture models can recapitulate many of the key cellular processes of nervous system development, including neurite outgrowth, and may be used as screening tools to identify potential developmental neurotoxicants. The present study compared primary rat cortical cultures and human embryonic stem cell-derived neural cultures in terms of: 1) reproducibility of high content image analysis based neurite outgrowth measurements, 2) dynamic range of neurite outgrowth measurements and 3) sensitivity to chemicals which have been shown to inhibit neurite outgrowth. There was a large increase in neurite outgrowth between 2 and 24 h in both rat and human cultures. Image analysis data collected across multiple cultures demonstrated that neurite outgrowth measurements in rat cortical cultures were more reproducible and had higher dynamic range as compared to human neural cultures. Human neural cultures were more sensitive than rat cortical cultures to chemicals previously shown to inhibit neurite outgrowth. Parallel analysis of morphological (neurite count, neurite length) and cytotoxicity (neurons per field) measurements were used to detect selective effects on neurite outgrowth. All chemicals which inhibited neurite outgrowth in rat cortical cultures did so at concentrations which did not concurrently affect the number of neurons per field, indicating selective effects on neurite outgrowth. In contrast, more than half the chemicals which inhibited neurite outgrowth in human neural cultures did so at concentrations which concurrently decreased the number of neurons per field, indicating that effects on neurite outgrowth were secondary to cytotoxicity. Overall, these data demonstrate that the culture models performed differently in terms of reproducibility, dynamic range and sensitivity to neurite outgrowth inhibitors. While human neural

The output of neuronotrophic and neurite-promoting agents from rat brain astroglial cells: a microculture method for screening potential regulatory molecules.

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Rudge, J S; Manthorpe, M; Varon, S

1985-04-01

Throughout embryonic development, as well as in response to injury of the central nervous system, astroglial cells may present neurons with a critical supply of neuronotrophic and neurite-promoting factors which control, respectively, neuronal survival and axonal growth. The identification of such astroglial cell-derived factors, as well as of specific extrinsic agents regulating their production, will require the use of in vitro techniques. We define here a new microculture system in which added agents can be screened for their ability to enhance or inhibit the output of trophic and neurite-promoting factors from purified neonatal rat brain astroglial cells. With such a procedure, thousands of replicate secondary astroglial cultures can be set-up and maintained in chemically defined medium, on a defined substratum and in a viable, low proliferative stable state. These cultured astroglial cells release into their medium at least three distinct and separable types of agents addressing nerve cells in vitro: (i) high molecular weight trophic factors (Mr greater than 10,000) which support the survival of embryonic peripheral neurons; (ii) low molecular weight trophic agents (Mr less than 10,000) supporting embryonic central neurons; and (iii) polyornithine-binding neurite-promoting factors which enhance neuritic regeneration for both peripheral and central neurons. The temporal release patterns of these three agents from astroglial cultures are quite distinct suggesting that their output is independently regulated.

IL-10 Promotes Neurite Outgrowth and Synapse Formation in Cultured Cortical Neurons after the Oxygen-Glucose Deprivation via JAK1/STAT3 Pathway.

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Chen, Hongbin; Lin, Wei; Zhang, Yixian; Lin, Longzai; Chen, Jianhao; Zeng, Yongping; Zheng, Mouwei; Zhuang, Zezhong; Du, Houwei; Chen, Ronghua; Liu, Nan

2016-07-26

As a classic immunoregulatory and anti-inflammatory cytokine, interleukin-10 (IL-10) provides neuroprotection in cerebral ischemia in vivo or oxygen-glucose deprivation (OGD)-induced injury in vitro. However, it remains blurred whether IL-10 promotes neurite outgrowth and synapse formation in cultured primary cortical neurons after OGD injury. In order to evaluate its effect on neuronal apoptosis, neurite outgrowth and synapse formation, we administered IL-10 or IL-10 neutralizing antibody (IL-10NA) to cultured rat primary cortical neurons after OGD injury. We found that IL-10 treatment activated the Janus kinase 1 (JAK1)/signal transducers and activators of transcription 3 (STAT3) signaling pathway. Moreover, IL-10 attenuated OGD-induced neuronal apoptosis by down-regulating the Bax expression and up-regulating the Bcl-2 expression, facilitated neurite outgrowth by increasing the expression of Netrin-1, and promoted synapse formation in cultured primary cortical neurons after OGD injury. These effects were partly abolished by JAK1 inhibitor GLPG0634. Contrarily, IL-10NA produced opposite effects on the cultured cortical neurons after OGD injury. Taken together, our findings suggest that IL-10 not only attenuates neuronal apoptosis, but also promotes neurite outgrowth and synapse formation via the JAK1/STAT3 signaling pathway in cultured primary cortical neurons after OGD injury.

Atorvastatin enhances neurite outgrowth in cortical neurons in vitro via up-regulating the Akt/mTOR and Akt/GSK-3β signaling pathways

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Jin, Ying; Sui, Hai-juan; Dong, Yan; Ding, Qi; Qu, Wen-hui; Yu, Sheng-xue; Jin, Ying-xin

2012-01-01

Aim: To investigate whether atorvastatin can promote formation of neurites in cultured cortical neurons and the signaling mechanisms responsible for this effect. Methods: Cultured rat cerebral cortical neurons were incubated with atorvastatin (0.05–10 μmol/L) for various lengths of time. For pharmacological experiments, inhibitors were added 30 min prior to addition of atorvastatin. Control cultures received a similar amount of DMSO. Following the treatment period, phase-contrast digital images were taken. Digital images of neurons were analyzed for total neurite branch length (TNBL), neurite number, terminal branch number, and soma area by SPOT Advanced Imaging software. After incubation with atorvastatin for 48 h, the levels of phosphorylated 3-phosphoinoside-dependent protein kinase-1 (PDK1), phospho-Akt, phosphorylated mammalian target of rapamycin (mTOR), phosphorylated 4E-binding protein 1 (4E-BP1), p70S6 kinase (p70S6K), and glycogen synthase kinase-3β (GSK-3β) in the cortical neurons were evaluated using Western blotting analyses. Results: Atorvastatin (0.05–10 μmol/L) resulted in dose-dependent increase in neurite number and length in these neurons. Pretreatment of the cortical neurons with phosphatidylinositol 3-kinase (PI3K) inhibitors LY294002 (30 μmol/L) and wortmannin (5 μmol/L), Akt inhibitor tricribine (1 μmol/L) or mTOR inhibitor rapamycin (100 nmol/L) blocked the atorvastatin-induced increase in neurite outgrowth, suggesting that atorvastatin promoted neurite outgrowth via activating the PI3K/Akt/mTOR signaling pathway. Atorvastatin (10 μmol/L) significantly increased the levels of phosphorylated PDK1, Akt and mTOR in the cortical neurons, which were prevented by LY294002 (30 μmol/L). Moreover, atorvastatin (10 μmol/L) stimulated the phosphorylation of 4E-BP1 and p70S6K, the substrates of mTOR, in the cortical neurons. In addition, atorvastatin (10 μmol/L) significantly increased the phosphorylated GSK-3β level in the cortical

Charge-balanced biphasic electrical stimulation inhibits neurite extension of spiral ganglion neurons.

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Shen, Na; Liang, Qiong; Liu, Yuehong; Lai, Bin; Li, Wen; Wang, Zhengmin; Li, Shufeng

2016-06-15

Intracochlear application of exogenous or transgenic neurotrophins, such as neurotrophin-3 (NT-3) and brain derived neurotrophic factor (BDNF), could promote the resprouting of spiral ganglion neuron (SGN) neurites in deafened animals. These resprouting neurites might reduce the gap between cochlear implant electrodes and their targeting SGNs, allowing for an improvement of spatial resolution of electrical stimulation. This study is to investigate the impact of electrical stimulation employed in CI on the extension of resprouting SGN neurites. We established an in vitro model including the devices delivering charge-balanced biphasic electrical stimulation, and spiral ganglion (SG) dissociated culture treated with BDNF and NT-3. After electrical stimulation with varying durations and intensities, we quantified neurite lengths and Schwann cell densities in SG cultures. Stimulations that were greater than 50μA or longer than 8h significantly decreased SG neurite length. Schwann cell density under 100μA electrical stimulation for 48h was significantly lower compared to that in non-stimulated group. These electrical stimulation-induced decreases of neurite extension and Schwann cell density were attenuated by various types of voltage-dependent calcium channel (VDCC) blockers, or completely prevented by their combination, cadmium or calcium-free medium. Our study suggested that charge-balanced biphasic electrical stimulation inhibited the extension of resprouting SGN neurites and decreased Schwann cell density in vitro. Calcium influx through multiple types of VDCCs was involved in the electrical stimulation-induced inhibition. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Neurotrophins differentially stimulate the growth of cochlear neurites on collagen surfaces and in gels☆

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Xie, Joanna; Pak, Kwang; Evans, Amaretta; Kamgar-Parsi, Andy; Fausti, Stephen; Mullen, Lina; Ryan, Allen Frederic

2013-01-01

The electrodes of a cochlear implant are located far from the surviving neurons of the spiral ganglion, which results in decreased precision of neural activation compared to the normal ear. If the neurons could be induced to extend neurites toward the implant, it might be possible to stimulate more discrete subpopulations of neurons, and to increase the resolution of the device. However, a major barrier to neurite growth toward a cochlear implant is the fluid filling the scala tympani, which separates the neurons from the electrodes. The goal of this study was to evaluate the growth of cochlear neurites in three-dimensional extracellular matrix molecule gels, and to increase biocompatibility by using fibroblasts stably transfected to produce neurotrophin-3 and brain-derived neurotrophic factor. Spiral ganglion explants from neonatal rats were evaluated in cultures. They were exposed to soluble neurotrophins, cells transfected to secrete neurotrophins, and/or collagen gels. We found that cochlear neurites grew readily on collagen surfaces and in three-dimensional collagen gels. Co-culture with cells producing neurotrophin-3 resulted in increased numbers of neurites, and neurites that were longer than when explants were cultured with control fibroblasts stably transfected with green fluorescent protein. Brain-derived neurotrophic factor-producing cells resulted in a more dramatic increase in the number of neurites, but there was no significant effect on neurite length. It is suggested that extracellular matrix molecule gels and cells transfected to produce neurotrophins offer an opportunity to attract spiral ganglion neurites toward a cochlear implant. PMID:24459465

Chimeric ZHHH neuroglobin acts as a cell membrane-penetrating inducer of neurite outgrowth.

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Takahashi, Nozomu; Onozuka, Wataru; Watanabe, Seiji; Wakasugi, Keisuke

2017-09-01

Neuroglobin (Ngb) is a heme protein expressed in the vertebrate brain. We previously engineered a chimeric Ngb protein, in which module M1 of human Ngb is replaced by that of zebrafish Ngb, and showed that the chimeric ZHHH Ngb has a cell membrane-penetrating activity similar to that of zebrafish Ngb and also rescues cells from death caused by hypoxia/reoxygenation as does human Ngb. Recently, it was reported that overexpression of mammalian Ngb in neuronal cells induces neurite outgrowth. In this study, we performed neurite outgrowth assays of chimeric Ngb using rat pheochromocytoma PC12 cells. Addition of chimeric Ngb, but not human or zebrafish Ngb, exogenously to the cell medium induces neurite outgrowth. On the other hand, the K7A/K9Q chimeric Ngb double mutant, which cannot translocate into cells, did not induce neurite outgrowth, suggesting that the cell membrane-penetrating activity of the chimeric Ngb is crucial for its neurite outgrowth-promoting activity. We also prepared several site-directed chimeric Ngb mutants and demonstrated that residues crucial for neurite outgrowth-inducing activity of the chimeric Ngb are not exactly the same as those for its neuroprotective activity.

Conversion Disorder Presenting As Neuritic Leprosy

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Sayal SK

2000-01-01

Full Text Available Conversion disorder is not normally listed amongst the conditions in differential diagnosis of leprosy neuropathy. A case conversion reaction who was initially diagnosed as neuritic leprosy is reported. Patient responded to narcosuggestion and psychotherapy.

Electrospun fiber surface nanotopography influences astrocyte-mediated neurite outgrowth.

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Johnson, Christopher D; D'Amato, Anthony R; Puhl, Devan L; Wich, Douglas M; Vespermann, Amanda; Gilbert, Ryan J

2018-05-15

Aligned, electrospun fiber scaffolds provide topographical guidance for regenerating neurons and glia after central nervous system injury. To date, no study has explored how fiber surface nanotopography affects astrocyte response to fibrous scaffolds. Astrocytes play important roles in the glial scar, the blood brain barrier, and in maintaining homeostasis in the central nervous system. In this study, electrospun poly L-lactic acid fibers were engineered with smooth, pitted, or divoted surface nanotopography. Cortical or spinal cord primary rat astrocytes were cultured on the surfaces for either 1 or 3 days to examine the astrocyte response over time. The results showed that cortical astrocytes were significantly shorter and broader on the pitted and divoted fibers compared to those on smooth fibers. However, spinal cord astrocyte morphology was not significantly altered by the surface features. These findings indicate that astrocytes from unique anatomical locations respond differently to the presence of nanotopography. Western Blot results show that the differences in morphology were not associated with significant changes in GFAP or vinculin in either astrocyte population, suggesting that surface pits and divots do not induce a reactive phenotype in either cortical or spinal cord astrocytes. Finally, astrocytes were co-cultured with dorsal root ganglia to determine how the surfaces affected astrocyte-mediated neurite outgrowth. Astrocytes cultured on the fibers for shorter periods of time (1 day) generally supported longer neurite outgrowth. Pitted and divoted fibers restricted spinal cord astrocyte-mediated neurite outgrowth, while smooth fibers increased 3 day spinal cord astrocyte-mediated neurite outgrowth. In total, fiber surface nanotopography can influence astrocyte elongation and influence the capability of astrocytes to direct neurites. Therefore, fiber surface characteristics should be carefully controlled to optimize astrocyte-mediated axonal

Berberine, a natural antidiabetes drug, attenuates glucose neurotoxicity and promotes Nrf2-related neurite outgrowth

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Hsu, Ya-Yun [Department of Pharmacology, School of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Tseng, Yu-Ting [Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Lo, Yi-Ching, E-mail: yichlo@kmu.edu.tw [Department of Pharmacology, School of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China)

2013-11-01

Reactive oxygen intermediates production and apoptotic damage induced by high glucose are major causes of neuronal damage in diabetic neuropathy. Berberine (BBR), a natural antidiabetes drug with PI3K-activating activity, holds promise for diabetes because of its dual antioxidant and anti-apoptotic activities. We have previously reported that BBR attenuated H{sub 2}O{sub 2} neurotoxicity via activating the PI3K/Akt/Nrf2-dependent pathway. In this study, we further explored the novel protective mechanism of BBR on high glucose-induced apoptotic death and neurite damage of SH-SY5Y cells. Results indicated BBR (0.1–10 nM) significantly attenuated reactive oxygen species (ROS) production, nucleus condensation, and apoptotic death in high glucose-treated cells. However, AG1024, an inhibitor of insulin growth factor-1 (IGF-1) receptor, significantly abolished BBR protection against high glucose-induced neuronal death. BBR also increased Bcl-2 expression and decreased cytochrome c release. High glucose down-regulated IGF-1 receptor and phosphorylation of Akt and GSK-3β, the effects of which were attenuated by BBR treatment. BBR also activated nuclear erythroid 2-related factor 2 (Nrf2), the key antioxidative transcription factor, which is accompanied with up-regulation of hemeoxygenase-1 (HO-1). Furthermore, BBR markedly enhanced nerve growth factor (NGF) expression and promoted neurite outgrowth in high glucose-treated cells. To further determine the role of the Nrf2 in BBR neuroprotection, RNA interference directed against Nrf2 was used. Results indicated Nrf2 siRNA abolished BBR-induced HO-1, NGF, neurite outgrowth and ROS decrease. In conclusion, BBR attenuated high glucose-induced neurotoxicity, and we are the first to reveal this novel mechanism of BBR as an Nrf2 activator against glucose neurotoxicity, providing another potential therapeutic use of BBR on the treatment of diabetic complications. - Highlights: • BBR attenuates high glucose-induced ROS

Berberine, a natural antidiabetes drug, attenuates glucose neurotoxicity and promotes Nrf2-related neurite outgrowth

International Nuclear Information System (INIS)

Hsu, Ya-Yun; Tseng, Yu-Ting; Lo, Yi-Ching

2013-01-01

Reactive oxygen intermediates production and apoptotic damage induced by high glucose are major causes of neuronal damage in diabetic neuropathy. Berberine (BBR), a natural antidiabetes drug with PI3K-activating activity, holds promise for diabetes because of its dual antioxidant and anti-apoptotic activities. We have previously reported that BBR attenuated H 2 O 2 neurotoxicity via activating the PI3K/Akt/Nrf2-dependent pathway. In this study, we further explored the novel protective mechanism of BBR on high glucose-induced apoptotic death and neurite damage of SH-SY5Y cells. Results indicated BBR (0.1–10 nM) significantly attenuated reactive oxygen species (ROS) production, nucleus condensation, and apoptotic death in high glucose-treated cells. However, AG1024, an inhibitor of insulin growth factor-1 (IGF-1) receptor, significantly abolished BBR protection against high glucose-induced neuronal death. BBR also increased Bcl-2 expression and decreased cytochrome c release. High glucose down-regulated IGF-1 receptor and phosphorylation of Akt and GSK-3β, the effects of which were attenuated by BBR treatment. BBR also activated nuclear erythroid 2-related factor 2 (Nrf2), the key antioxidative transcription factor, which is accompanied with up-regulation of hemeoxygenase-1 (HO-1). Furthermore, BBR markedly enhanced nerve growth factor (NGF) expression and promoted neurite outgrowth in high glucose-treated cells. To further determine the role of the Nrf2 in BBR neuroprotection, RNA interference directed against Nrf2 was used. Results indicated Nrf2 siRNA abolished BBR-induced HO-1, NGF, neurite outgrowth and ROS decrease. In conclusion, BBR attenuated high glucose-induced neurotoxicity, and we are the first to reveal this novel mechanism of BBR as an Nrf2 activator against glucose neurotoxicity, providing another potential therapeutic use of BBR on the treatment of diabetic complications. - Highlights: • BBR attenuates high glucose-induced ROS production and

A neurite quality index and machine vision software for improved quantification of neurodegeneration.

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Romero, Peggy; Miller, Ted; Garakani, Arman

2009-12-01

Current methods to assess neurodegradation in dorsal root ganglion cultures as a model for neurodegenerative diseases are imprecise and time-consuming. Here we describe two new methods to quantify neuroprotection in these cultures. The neurite quality index (NQI) builds upon earlier manual methods, incorporating additional morphological events to increase detection sensitivity for the detection of early degeneration events. Neurosight is a machine vision-based method that recapitulates many of the strengths of NQI while enabling high-throughput screening applications with decreased costs.

Solo/Trio8, a membrane-associated short isoform of Trio, modulates endosome dynamics and neurite elongation.

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Sun, Ying-Jie; Nishikawa, Kaori; Yuda, Hideki; Wang, Yu-Lai; Osaka, Hitoshi; Fukazawa, Nobuna; Naito, Akira; Kudo, Yoshihisa; Wada, Keiji; Aoki, Shunsuke

2006-09-01

With DNA microarrays, we identified a gene, termed Solo, that is downregulated in the cerebellum of Purkinje cell degeneration mutant mice. Solo is a mouse homologue of rat Trio8-one of multiple Trio isoforms recently identified in rat brain. Solo/Trio8 contains N-terminal sec14-like and spectrin-like repeat domains followed by a single guanine nucleotide exchange factor 1 (GEF1) domain, but it lacks the C-terminal GEF2, immunoglobulin-like, and kinase domains that are typical of Trio. Solo/Trio8 is predominantly expressed in Purkinje neurons of the mouse brain, and expression begins following birth and increases during Purkinje neuron maturation. We identified a novel C-terminal membrane-anchoring domain in Solo/Trio8 that is required for enhanced green fluorescent protein-Solo/Trio8 localization to early endosomes (positive for both early-endosome antigen 1 [EEA1] and Rab5) in COS-7 cells and primary cultured neurons. Solo/Trio8 overexpression in COS-7 cells augmented the EEA1-positive early-endosome pool, and this effect was abolished via mutation and inactivation of the GEF domain or deletion of the C-terminal membrane-anchoring domain. Moreover, primary cultured neurons transfected with Solo/Trio8 showed increased neurite elongation that was dependent on these domains. These results suggest that Solo/Trio8 acts as an early-endosome-specific upstream activator of Rho family GTPases for neurite elongation of developing Purkinje neurons.

Slit2 inactivates GSK3β to signal neurite outgrowth inhibition.

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Justin Byun

Full Text Available Slit molecules comprise one of the four canonical families of axon guidance cues that steer the growth cone in the developing nervous system. Apart from their role in axon pathfinding, emerging lines of evidence suggest that a wide range of cellular processes are regulated by Slit, ranging from branch formation and fasciculation during neurite outgrowth to tumor progression and to angiogenesis. However, the molecular and cellular mechanisms downstream of Slit remain largely unknown, in part, because of a lack of a readily manipulatable system that produces easily identifiable traits in response to Slit. The present study demonstrates the feasibility of using the cell line CAD as an assay system to dissect the signaling pathways triggered by Slit. Here, we show that CAD cells express receptors for Slit (Robo1 and Robo2 and that CAD cells respond to nanomolar concentrations of Slit2 by markedly decelerating the rate of process extension. Using this system, we reveal that Slit2 inactivates GSK3β and that inhibition of GSK3β is required for Slit2 to inhibit process outgrowth. Furthermore, we show that Slit2 induces GSK3β phosphorylation and inhibits neurite outgrowth in adult dorsal root ganglion neurons, validating Slit2 signaling in primary neurons. Given that CAD cells can be conveniently manipulated using standard molecular biological methods and that the process extension phenotype regulated by Slit2 can be readily traced and quantified, the use of a cell line CAD will facilitate the identification of downstream effectors and elucidation of signaling cascade triggered by Slit.

Endothelin-2/Vasoactive Intestinal Contractor: Regulation of Expression via Reactive Oxygen Species Induced by CoCl22, and Biological Activities Including Neurite Outgrowth in PC12 Cells

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Eiichi Kotake-Nara

2006-01-01

Full Text Available This paper reviews the local hormone endothelin-2 (ET-2, or vasoactive intestinal contractor (VIC, a member of the vasoconstrictor ET peptide family, where ET-2 is the human orthologous peptide of the murine VIC. While ET-2/VIC gene expression has been observed in some normal tissues, ET-2 recently has been reported to act as a tumor marker and as a hypoxia-induced autocrine survival factor in tumor cells. A recently published study reported that the hypoxic mimetic agent CoCl2 at 200 µM increased expression of the ET-2/VIC gene, decreased expression of the ET-1 gene, and induced intracellular reactive oxygen species (ROS increase and neurite outgrowth in neuronal model PC12 cells. The ROS was generated by addition of CoCl2 to the culture medium, and the CoCl2-induced effects were completely inhibited by the antioxidant N-acetyl cysteine. Furthermore, interleukin-6 (IL-6 gene expression was up-regulated upon the differentiation induced by CoCl2. These results suggest that expression of ET-2/VIC and ET-1 mediated by CoCl2-induced ROS may be associated with neuronal differentiation through the regulation of IL-6 expression. CoCl2 acts as a pro-oxidant, as do Fe(II, III and Cu(II. However, some biological activities have been reported for CoCl2 that have not been observed for other metal salts such as FeCl3, CuSO4, and NiCl2. The characteristic actions of CoCl2 may be associated with the differentiation of PC12 cells. Further elucidation of the mechanism of neurite outgrowth and regulation of ET-2/VIC expression by CoCl2 may lead to the development of treatments for neuronal disorders.

Microelectrode array-induced neuronal alignment directs neurite outgrowth: analysis using a fast Fourier transform (FFT).

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Radotić, Viktorija; Braeken, Dries; Kovačić, Damir

2017-12-01

Many studies have shown that the topography of the substrate on which neurons are cultured can promote neuronal adhesion and guide neurite outgrowth in the same direction as the underlying topography. To investigate this effect, isotropic substrate-complementary metal-oxide-semiconductor (CMOS) chips were used as one example of microelectrode arrays (MEAs) for directing neurite growth of spiral ganglion neurons. Neurons were isolated from 5 to 7-day-old rat pups, cultured 1 day in vitro (DIV) and 4 DIV, and then fixed with 4% paraformaldehyde. For analysis of neurite alignment and orientation, fast Fourier transformation (FFT) was used. Results revealed that on the micro-patterned surface of a CMOS chip, neurons orient their neurites along three directional axes at 30, 90, and 150° and that neurites aligned in straight lines between adjacent pillars and mostly followed a single direction while occasionally branching perpendicularly. We conclude that the CMOS substrate guides neurites towards electrodes by means of their structured pillar organization and can produce electrical stimulation of aligned neurons as well as monitoring their neural activities once neurites are in the vicinity of electrodes. These findings are of particular interest for neural tissue engineering with the ultimate goal of developing a new generation of MEA essential for improved electrical stimulation of auditory neurons.

Bifenthrin inhibits neurite outgrowth in differentiating PC12 cells.

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Tran, Van; Hoffman, Natalie; Mofunanaya, Adaobi; Pryor, Stephen C; Ojugbele, Olutosin; McLaughlin, Ashlea; Gibson, Lydia; Bonventre, Josephine A; Flynn, Katherine; Weeks, Benjamin S

2006-02-01

Bifenthrin is a third generation member of the synthetic pyrethroid family of insecticides. As a new pesticide within a relatively new class of pesticides, bifenthrin is considered relatively safe. Here, we used the PC12 neuronal cell line to examine the effect of bifenthrin on the formation of neurites and the potential developmental neurotoxicity of this pesticide. PC12 cells were exposed to varying concentrations of technical grade bifenthrin or Ortho Home Defense. Cell viability was determined using the AlmarBlue Toxicity Assay. Nontoxic concentrations of these chemicals were concomitantly with nerve growth factor and neurite outgrowth was assessed. Ortho Home Defense preparation reduced PC12 cell viability by approximately 50% and 70% at dilutions that correlate to bifenthrin concentrations of 10(-5) M and 10(-4) M, respectively. In contrast, technical grade bifenthrin, was not toxic to PC12 cells at 10(-3) M, which was the highest concentration tested that was soluble. At "nontoxic" concentrations of 10(-7) M and 10(-6) M, the Ortho Home Defense inhibited nerve growth factor-mediated neurite outgrowth by 30% and 55% respectively. Furthermore the nontoxic concentrations of technical grade bifenthrin of 10(-6) M and 10(-3) M inhibited neurite outgrowth by approximately 35% and 75% respectively. These data suggest that the toxicity of the Ortho Home Defense preparation was due to the "inert" additives in the preparation and not the bifenthrin itself. Further, these data suggest that, even in the absence of overt toxicity, bifenthrin may have deleterious effects to developing nervous system.

Sigma-1 receptor enhances neurite elongation of cerebellar granule neurons via TrkB signaling.

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Kimura, Yuriko; Fujita, Yuki; Shibata, Kumi; Mori, Megumi; Yamashita, Toshihide

2013-01-01

Sigma-1 receptor (Sig-1R) is an integral membrane protein predominantly expressed in the endoplasmic reticulum. Sig-1R demonstrates a high affinity to various synthetic compounds including well-known psychotherapeutic drugs in the central nervous system (CNS). For that, it is considered as an alternative target for psychotherapeutic drugs. On the cellular level, when Sig-1R is activated, it is known to play a role in neuroprotection and neurite elongation. These effects are suggested to be mediated by its ligand-operated molecular chaperone activity, and/or upregulation of various Ca(2+) signaling. In addition, recent studies show that Sig-1R activation induces neurite outgrowth via neurotrophin signaling. Here, we tested the hypothesis that Sig-1R activation promotes neurite elongation through activation of tropomyosin receptor kinase (Trk), a family of neurotrophin receptors. We found that 2-(4-morpholinethyl)1-phenylcyclohexanecarboxylate (PRE-084), a selective Sig-1R agonist, significantly promoted neurite outgrowth, and K252a, a Trk inhibitor, attenuated Sig-1R-mediated neurite elongation in cerebellar granule neurons (CGNs). Moreover, we revealed that Sig-1R interacts with TrkB, and PRE-084 treatment enhances phosphorylation of Y515, but not Y706. Thus, our results indicate that Sig-1R activation promotes neurite outgrowth in CGNs through Y515 phosphorylation of TrkB.

[Inhibitory proteins of neuritic regeneration in the extracellular matrix: structure, molecular interactions and their functions. Mechanisms of extracellular balance].

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Vargas, Javier; Uribe-Escamilla, Rebeca; Alfaro-Rodríguez, Alfonso

2013-01-01

After injury of the central nervous system (CNS) in higher vertebrates, neurons neither grow nor reconnect with their targets because their axons or dendrites cannot regenerate within the injured site. In the CNS, the signal from the environment regulating neurite regeneration is not exclusively generated by one molecular group. This signal is generated by the interaction of various types of molecules such as extracellular matrix proteins, soluble factors and surface membrane molecules; all these elements interact with one another generating the matrix's biological state: the extracellular balance. Proteins in the balanced extracellular matrix, support and promote cellular physiological states, including neuritic regeneration. We have reviewed three types of proteins of the extracellular matrix possessing an inhibitory effect and that are determinant of neuritic regeneration failure in the CNS: chondroitin sulfate proteoglycans, keratan sulfate proteoglycans and tenascin. We also review some of the mechanisms involved in the balance of extracellular proteins such as isomerization, epimerization, sulfation and glycosylation as well as the assemblage of the extracellular matrix, the interaction between the matrix and soluble factors and its proteolytic degradation. In the final section, we have presented some examples of the matrix's role in development and in tumor propagation.

The prescriptions from Shenghui soup enhanced neurite growth and GAP-43 expression level in PC12 cells.

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Zhang, Qi; Zhang, Zi-Jian; Wang, Xing-Hua; Ma, Jie; Song, Yue-Han; Liang, Mi; Lin, Sen-Xiang; Zhao, Jie; Zhang, Ao-Zhe; Li, Feng; Hua, Qian

2016-09-20

Shenghui soup is a traditional Chinese herbal medicine used in clinic for the treatment of forgetfulness. In order to understanding the prescription principle, the effects of "tonifying qi and strengthening spleen" group (TQSS) including Poria cocos (Schw.) Wolf. and Panax ginseng C.A.Mey and "eliminating phlegm and strengthening intelligence" group (EPSI) composed of Polygala tenuifolia Willd., Acorus calamus L. and Sinapis alba L from the herb complex on neurite growth in PC12 cells, two disassembled prescriptions derived from Shenghui soup and their molecular mechanisms were investigated. Firstly, CCK-8 kit was used to detect the impact of the two prescriptions on PC12 cell viability; and Flow cytometry was performed to measure the cell apoptosis when PC12 cells were treated with these drugs. Secondly, the effect of the two prescriptions on the differentiation of PC12 cells was observed. Finally, the mRNA and protein expression levels of GAP-43 were analyzed by RT-PCR and western blot, respectively. "Tonifying qi and strengthening spleen" prescription decreased cell viability in a dose-dependent manner, but had no significant effect on cell apoptosis. Meanwhile, it could improve neurite growth and elevate the mRNA and protein expression level of GAP-43. "Eliminating phlegm and strengthening intelligence" prescription also exerted the similar effects on cell viability and apoptosis. Furthermore, it could also enhance cell neurite growth, with a higher expression level of GAP-43 mRNA and protein. "Tonifying qi and strengthening spleen" and "eliminating phlegm and strengthening intelligence" prescriptions from Shenghui soup have a positive effect on neurite growth. Their effects are related to the up-regulating expression of GAP-43.

Glial membranes at the node of Ranvier prevent neurite outgrowth

DEFF Research Database (Denmark)

Huang, Jeffrey K; Phillips, Greg R; Roth, Alejandro D

2005-01-01

of neurite outgrowth, including the oligodendrocyte myelin glycoprotein (OMgp). In rat spinal cord, OMgp was not localized to compact myelin, as previously thought, but to oligodendroglia-like cells, whose processes converge to form a ring that completely encircles the nodes. In OMgp-null mice, CNS nodes......Nodes of Ranvier are regularly placed, nonmyelinated axon segments along myelinated nerves. Here we show that nodal membranes isolated from the central nervous system (CNS) of mammals restricted neurite outgrowth of cultured neurons. Proteomic analysis of these membranes revealed several inhibitors...

Light-Mediated Kinetic Control Reveals the Temporal Effect of the Raf/MEK/ERK Pathway in PC12 Cell Neurite Outgrowth

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Zhang, Kai; Duan, Liting; Ong, Qunxiang; Lin, Ziliang; Varman, Pooja Mahendra; Sung, Kijung; Cui, Bianxiao

2014-01-01

It has been proposed that differential activation kinetics allows cells to use a common set of signaling pathways to specify distinct cellular outcomes. For example, nerve growth factor (NGF) and epidermal growth factor (EGF) induce different activation kinetics of the Raf/MEK/ERK signaling pathway and result in differentiation and proliferation, respectively. However, a direct and quantitative linkage between the temporal profile of Raf/MEK/ERK activation and the cellular outputs has not been established due to a lack of means to precisely perturb its signaling kinetics. Here, we construct a light-gated protein-protein interaction system to regulate the activation pattern of the Raf/MEK/ERK signaling pathway. Light-induced activation of the Raf/MEK/ERK cascade leads to significant neurite outgrowth in rat PC12 pheochromocytoma cell lines in the absence of growth factors. Compared with NGF stimulation, light stimulation induces longer but fewer neurites. Intermittent on/off illumination reveals that cells achieve maximum neurite outgrowth if the off-time duration per cycle is shorter than 45 min. Overall, light-mediated kinetic control enables precise dissection of the temporal dimension within the intracellular signal transduction network. PMID:24667437

Activation of transglutaminase 2 by nerve growth factor in differentiating neuroblastoma cells: A role in cell survival and neurite outgrowth.

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Algarni, Alanood S; Hargreaves, Alan J; Dickenson, John M

2018-02-05

NGF (nerve growth factor) and tissue transglutaminase (TG2) play important roles in neurite outgrowth and modulation of neuronal cell survival. In this study, we investigated the regulation of TG2 transamidase activity by NGF in retinoic acid-induced differentiating mouse N2a and human SH-SY5Y neuroblastoma cells. TG2 transamidase activity was determined using an amine incorporation and a peptide cross linking assay. In situ TG2 activity was assessed by visualising the incorporation of biotin-X-cadaverine using confocal microscopy. The role of TG2 in NGF-induced cytoprotection and neurite outgrowth was investigated by monitoring hypoxia-induced cell death and appearance of axonal-like processes, respectively. The amine incorporation and protein crosslinking activity of TG2 increased in a time and concentration-dependent manner following stimulation with NGF in N2a and SH-SY5Y cells. NGF mediated increases in TG2 activity were abolished by the TG2 inhibitors Z-DON (Z-ZON-Val-Pro-Leu-OMe; Benzyloxycarbonyl-(6-Diazo-5-oxonorleucinyl)-l-valinyl-l-prolinyl-l-leucinmethylester) and R283 (1,3,dimethyl-2[2-oxo-propyl]thio)imidazole chloride) and by pharmacological inhibition of extracellular signal-regulated kinases 1 and 2 (ERK1/2), protein kinase B (PKB) and protein kinase C (PKC), and removal of extracellular Ca 2+ . Fluorescence microscopy demonstrated NGF induced in situ TG2 activity. TG2 inhibition blocked NGF-induced attenuation of hypoxia-induced cell death and neurite outgrowth in both cell lines. Together, these results demonstrate that NGF stimulates TG2 transamidase activity via a ERK1/2, PKB and PKC-dependent pathway in differentiating mouse N2a and human SH-SY5Y neuroblastoma cells. Furthermore, NGF-induced cytoprotection and neurite outgrowth are dependent upon TG2. These results suggest a novel and important role of TG2 in the cellular functions of NGF. Copyright © 2017 Elsevier B.V. All rights reserved.

Neuronal adaptor FE65 stimulates Rac1-mediated neurite outgrowth by recruiting and activating ELMO1.

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Li, Wen; Tam, Ka Ming Vincent; Chan, Wai Wan Ray; Koon, Alex Chun; Ngo, Jacky Chi Ki; Chan, Ho Yin Edwin; Lau, Kwok-Fai

2018-04-03

Neurite outgrowth is a crucial process in developing neurons for neural network formation. Understanding the regulatory mechanisms of neurite outgrowth is essential for developing strategies to stimulate neurite regeneration after nerve injury and in neurodegenerative disorders. FE65 is a brain-enriched adaptor that stimulates Rac1-mediated neurite elongation. However, the precise mechanism by which FE65 promotes the process remains elusive. Here, we show that ELMO1, a subunit of ELMO1-DOCK180 bipartite Rac1 GEF, interacts with the FE65 N-terminal region. Overexpression of FE65 and/or ELMO1 enhances whereas knockdown of FE65 or ELMO1 inhibits neurite outgrowth and Rac1 activation. The effect of FE65 alone or together with ELMO1 is attenuated by an FE65 double mutation that disrupts FE65-ELMO1 interaction. Notably, FE65 is found to activate ELMO1 by diminishing ELMO1 intramolecular autoinhibitory interaction and to promote the targeting of ELMO1 to the plasma membrane where Rac1 is activated. We also show that FE65, ELMO1 and DOCK180 form a tripartite complex. Knockdown of DOCK180 reduces the stimulatory effect of FE65-ELMO1 on Rac1 activation and neurite outgrowth. Thus, we identify a novel mechanism that FE65 stimulates Rac1-mediated neurite outgrowth by recruiting and activating of ELMO1. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

GIT1 enhances neurite outgrowth by stimulating microtubule assembly

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Yi-sheng Li

2016-01-01

Full Text Available GIT1, a G-protein-coupled receptor kinase interacting protein, has been reported to be involved in neurite outgrowth. However, the neurobiological functions of the protein remain unclear. In this study, we found that GIT1 was highly expressed in the nervous system, and its expression was maintained throughout all stages of neuritogenesis in the brain. In primary cultured mouse hippocampal neurons from GIT1 knockout mice, there was a significant reduction in total neurite length per neuron, as well as in the average length of axon-like structures, which could not be prevented by nerve growth factor treatment. Overexpression of GIT1 significantly promoted axon growth and fully rescued the axon outgrowth defect in the primary hippocampal neuron cultures from GIT1 knockout mice. The GIT1 N terminal region, including the ADP ribosylation factor-GTPase activating protein domain, the ankyrin domains and the Spa2 homology domain, were sufficient to enhance axonal extension. Importantly, GIT1 bound to many tubulin proteins and microtubule-associated proteins, and it accelerated microtubule assembly in vitro. Collectively, our findings suggest that GIT1 promotes neurite outgrowth, at least partially by stimulating microtubule assembly. This study provides new insight into the cellular and molecular pathogenesis of GIT1-associated neurological diseases.

Applied electric field enhances DRG neurite growth: influence of stimulation media, surface coating and growth supplements

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Wood, Matthew D.; Willits, Rebecca Kuntz

2009-08-01

Electrical therapies have been found to aid repair of nerve injuries and have been shown to increase and direct neurite outgrowth during stimulation. This enhanced neural growth existed even after the electric field (EF) or stimulation was removed, but the factors that may influence the enhanced growth, such as stimulation media or surface coating, have not been fully investigated. This study characterized neurite outgrowth and branching under various conditions: EF magnitude and application time, ECM surface coating, medium during EF application and growth supplements. A uniform, low-magnitude EF (24 or 44 V m-1) was applied to dissociated chick embryo dorsal root ganglia seeded on collagen or laminin-coated surfaces. During the growth period, cells were either exposed to NGF or N2, and during stimulation cells were exposed to either unsupplemented media (Ca2+) or PBS (no Ca2+). Parallel controls for each experiment included cells exposed to the chamber with no stimulation and cells remaining outside the chamber. After brief electrical stimulation (10 min), neurite length significantly increased 24 h after application for all conditions studied. Of particular interest, increased stimulation time (10-100 min) further enhanced neurite length on laminin but not on collagen surfaces. Neurite branching was not affected by stimulation on any surface, and no preferential growth of neurites was noted after stimulation. Overall, the results of this report suggest that short-duration electric stimulation is sufficient to enhance neurite length under a variety of conditions. While further data are needed to fully elucidate a mechanism for this increased growth, these data suggest that one focus of those investigations should be the interaction between the growth cone and the substrata.

Prostaglandin E2 facilitates neurite outgrowth in a motor neuron-like cell line, NSC-34

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Hiroshi Nango

2017-10-01

Full Text Available Prostaglandin E2 (PGE2 exerts various biological effects by binding to E-prostanoid receptors (EP1-4. Although recent studies have shown that PGE2 induces cell differentiation in some neuronal cells such as mouse DRG neurons and sensory neuron-like ND7/23 cells, it is unclear whether PGE2 plays a role in differentiation of motor neurons. In the present study, we investigated the mechanism of PGE2-induced differentiation of motor neurons using NSC-34, a mouse motor neuron-like cell line. Exposure of undifferentiated NSC-34 cells to PGE2 and butaprost, an EP2-selective agonist, resulted in a reduction of MTT reduction activity without increase the number of propidium iodide-positive cells and in an increase in the number of neurite-bearing cells. Sulprostone, an EP1/3 agonist, also significantly lowered MTT reduction activity by 20%; however, no increase in the number of neurite-bearing cells was observed within the concentration range tested. PGE2-induced neurite outgrowth was attenuated significantly in the presence of PF-0441848, an EP2-selective antagonist. Treatment of these cells with dibutyryl-cAMP increased the number of neurite-bearing cells with no effect on cell proliferation. These results suggest that PGE2 promotes neurite outgrowth and suppresses cell proliferation by activating the EP2 subtype, and that the cAMP-signaling pathway is involved in PGE2-induced differentiation of NSC-34 cells. Keywords: Prostaglandin E2, E-prostanoid receptors, Motor neuron, Neurite outgrowth, cAMP

Discovery of pyrroloimidazoles as agents stimulating neurite outgrowth

NARCIS (Netherlands)

Beck, Barbara; Leppert, Christian A.; Mueller, Bernhard K.; Dömling, Alexander

2006-01-01

A diverse library of substituted pyrroloimidazoles was assembled by a multicomponent reaction (MCR) of tosylmethyl isocyanides (TOSMIC), indole carbaldehydes and primary amines in a van Leusen reaction. A library of this scaffold was screened in a phenotypic assay for neurite outgrowth. Several

Role of G protein-regulated inducer of neurite outgrowth 3 (GRIN3) in β-arrestin 2-Akt signaling and dopaminergic behaviors.

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Mototani, Yasumasa; Okamura, Tadashi; Goto, Motohito; Shimizu, Yukiko; Yanobu-Takanashi, Rieko; Ito, Aiko; Kawamura, Naoya; Yagisawa, Yuka; Umeki, Daisuke; Nariyama, Megumi; Suita, Kenji; Ohnuki, Yoshiki; Shiozawa, Kouichi; Sahara, Yoshinori; Kozasa, Tohru; Saeki, Yasutake; Okumura, Satoshi

2018-06-01

The G protein-regulated inducer of neurite growth (GRIN) family has three isoforms (GRIN1-3), which bind to the Gαi/o subfamily of G protein that mediate signal processing via G protein-coupled receptors (GPCRs). Here, we show that GRIN3 is involved in regulation of dopamine-dependent behaviors and is essential for activation of the dopamine receptors (DAR)-β-arrestin signaling cascade. Analysis of functional regions of GRIN3 showed that a di-cysteine motif (Cys751/752) is required for plasma membrane localization. GRIN3 was co-immunoprecipitated with GPCR kinases 2/6 and β-arrestins 1/2. Among GRINs, only GRIN3, which is highly expressed in striatum, strongly interacted with β-arrestin 2. We also generated GRIN3-knockout mice (GRIN3KO). GRIN3KO exhibited reduced locomotor activity and increased anxiety-like behavior in the elevated maze test, as well as a reduced locomoter response to dopamine stimulation. We also examined the phosphorylation of Akt at threonine 308 (phospho308-Akt), which is dephosphorylated via a β-arrestin 2-mediated pathway. Dephosphorylation of phospho308-Akt via the D2R-β-arrestin 2 signaling pathway was completely abolished in striatum of GRIN3KO. Our results suggest that GRIN3 has a role in recruitment and assembly of proteins involved in β-arrestin-dependent, G protein-independent signaling.

Quantifying Spiral Ganglion Neurite and Schwann Behavior on Micropatterned Polymer Substrates.

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Cheng, Elise L; Leigh, Braden; Guymon, C Allan; Hansen, Marlan R

2016-01-01

The first successful in vitro experiments on the cochlea were conducted in 1928 by Honor Fell (Fell, Arch Exp Zellforsch 7(1):69-81, 1928). Since then, techniques for culture of this tissue have been refined, and dissociated primary culture of the spiral ganglion has become a widely accepted in vitro model for studying nerve damage and regeneration in the cochlea. Additionally, patterned substrates have been developed that facilitate and direct neural outgrowth. A number of automated and semi-automated methods for quantifying this neurite outgrowth have been utilized in recent years (Zhang et al., J Neurosci Methods 160(1):149-162, 2007; Tapias et al., Neurobiol Dis 54:158-168, 2013). Here, we describe a method to study the effect of topographical cues on spiral ganglion neurite and Schwann cell alignment. We discuss our microfabrication process, characterization of pattern features, cell culture techniques for both spiral ganglion neurons and spiral ganglion Schwann cells. In addition, we describe protocols for reducing fibroblast count, immunocytochemistry, and methods for quantifying neurite and Schwann cell alignment.

Bifenthrin causes neurite retraction in the absence of cell death: a model for pesticide associated neurodegeneration.

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Nandi, Avishek; Chandil, Daljit; Lechesal, Rethabile; Pryor, Stephen C; McLaughlin, Ashlea; Bonventre, Josephine A; Flynnx, Katherine; Weeks, Benjamin S

2006-05-01

Bifenthrin is a synthetic pyrethroid insecticide derivative of naturally occurring pyrethrins from chrysanthemum flowers. Bifenthrin is considered relatively safe and therefore incorporated as the active ingredient in preparations sold over the counter for household use. Recent studies have raised concern that chronic exposure to pesticides in the home setting may increase the risk for neurodegenerative diseases. To address this concer, in the present study, bifenthrin is added to pre-differentiated PC12 and effect of bifenthrin on the retraction of existing neurites is observed a model for neurodegeneration. PC12 cells were differentiated with nerve growth factor for twenty-four hours and then treated with what was determined to be a sublethal dose of bifenthrin for up to an additional 48 hours. The percent of cells with neurites was assessed at various times before and after nerve growth factor treatment. Bifenthrin toxicity was determined using trypan blue exclusion. Bifenthrin was not toxic to PC12 cells at concentrations ranging from 1 x 10(-10) M to 1 x 10(-4) M. Twenty-four hours after nerve growth factor treatment, a maximum percent of cells had formed neurites and with a treatment of 1 x 10(-5) M bifenthrin, approximately 80% of these neurites retracted in within 12 additional hours and almost all neurites had retracted within 48 hours. Trypan exclusion showed that these cells were viable. These data show that bifenthrin can stimulate the retraction of neurites in the absence of frank toxicity.

Induction of neurite outgrowth in 3D hydrogel-based environments

International Nuclear Information System (INIS)

Assunção-Silva, Rita C; Oliveira, Cátia Costa; Gomes, Eduardo D; Sousa, Nuno; Silva, Nuno A; Salgado, António J; Ziv-Polat, Ofra; Sahar, Abraham

2015-01-01

The ability of peripheral nervous system (PNS) axons to regenerate and re-innervate their targets after an injury has been widely recognized. However, despite the considerable advances made in microsurgical techniques, complete functional recovery is rarely achieved, especially for severe peripheral nerve injuries (PNIs). Therefore, alternative therapies that can successfully repair peripheral nerves are still essential. In recent years the use of biodegradable hydrogels enriched with growth-supporting and guidance cues, cell transplantation, and biomolecular therapies have been explored for the treatment of PNIs. Bearing this in mind, the aim of this study was to assess whether Gly-Arg-Gly-Asp-Ser synthetic peptide (GRGDS)-modified gellan gum (GG) based hydrogels could foster an amenable environment for neurite/axonal growth. Additionally, strategies to further improve the rate of neurite outgrowth were also tested, namely the use of adipose tissue derived stem cells (ASCs), as well as the glial derived neurotrophic factor (GDNF). In order to increase its stability and enhance its bioactivity, the GDNF was conjugated covalently to iron oxide nanoparticles (IONPs). The impact of hydrogel modification as well as the effect of the GDNF-IONPs on ASC behavior was also screened. The results revealed that the GRGDS-GG hydrogel was able to support dorsal root ganglia (DRG)-based neurite outgrowth, which was not observed for non-modified hydrogels. Moreover, the modified hydrogels were also able to support ASCs attachment. In contrast, the presence of the GDNF-IONPs had no positive or negative impact on ASC behavior. Further experiments revealed that the presence of ASCs in the hydrogel improved axonal growth. On the other hand, GDNF-IONPs alone or combined with ASCs significantly increased neurite outgrowth from DRGs, suggesting a beneficial role of the proposed strategy for future applications in PNI regenerative medicine. (note)

miR-103 Promotes Neurite Outgrowth and Suppresses Cells Apoptosis by Targeting Prostaglandin-Endoperoxide Synthase 2 in Cellular Models of Alzheimer's Disease.

Science.gov (United States)

Yang, Hui; Wang, Hongcai; Shu, Yongwei; Li, Xuling

2018-01-01

miR-103 has been reported to be decreased in brain of transgenic mouse model of Alzheimer's disease (AD) and in cerebrospinal fluid (CSF) of AD patients, while the detailed mechanism of its effect on AD is obscure, thus this study aimed to investigate the effect of miR-103 expression on neurite outgrowth and cells apoptosis as well as its targets in cellular models of AD. Blank mimic (NC1-mimic), miR-103 mimic, blank inhibitor (NC2-mimic) and miR-103 inhibitor plasmids were transferred into PC12 cellular AD model and Cellular AD model of cerebral cortex neurons which were established by Aβ1-42 insult. Rescue experiment was subsequently performed by transferring Prostaglandin-endoperoxide synthase 2 (PTGS2) and miR-103 mimic plasmid. mRNA and protein expressions were detected by qPCR and Western Blot assays. Total neurite outgrowth was detected by microscope, cells apoptosis was determined by Hoechst/PI assay, and apoptotic markers Caspase 3 and p38 expressions were determined by Western Blot assay. In both PC12 and cerebral cortex neurons cellular AD models, miR-103 mimic increases the total neurite outgrowth compared with NC1-mimic, while miR-103 inhibitor decreases the total neurite outgrowth than NC2-inhibitor. The apoptosis rate was decreased in miR-103 mimic group than NC1-mimic group while increased in miR-103 inhibitor group than NC2-inhibitor group. PTGS2, Adisintegrin and metalloproteinase 10 (ADAM10) and neprilysin (NEP) were selected as target genes of miR-103 by bioinformatics analysis. And PTGS2 was found to be conversely regulated by miR-103 expression while ADAM10 and NEP were not affected. After transfection by PTGS2 and miR-103 mimic plasmid in PC12 cellular AD model, the total neurite growth was shortened compared with miR-103 mimic group, and cells apoptosis was enhanced which indicated PTGS2 mimic attenuated the influence of miR-103 mimic on progression of AD. In conclusion, miR-103 promotes total neurite outgrowth and inhibits cells apoptosis

Binding of Cdc42 to phospholipase D1 is important in neurite outgrowth of neural stem cells

International Nuclear Information System (INIS)

Yoon, Mee-Sup; Cho, Chan Ho; Lee, Ki Sung; Han, Joong-Soo

2006-01-01

We previously demonstrated that phospholipase D (PLD) expression and PLD activity are upregulated during neuronal differentiation. In the present study, employing neural stem cells from the brain cortex of E14 rat embryos, we investigated the role of Rho family GTPases in PLD activation and in neurite outgrowth of neural stem cells during differentiation. As neuronal differentiation progressed, the expression levels of Cdc42 and RhoA increased. Furthermore, Cdc42 and PLD1 were mainly localized in neurite, whereas RhoA was localized in cytosol. Co-immunoprecipitation revealed that Cdc42 was bound to PLD1 during differentiation, whereas RhoA was associated with PLD1 during both proliferation and differentiation. These results indicate that the association between Cdc42 and PLD1 is related to neuronal differentiation. To examine the effect of Cdc42 on PLD activation and neurite outgrowth, we transfected dominant negative Cdc42 (Cdc42N17) and constitutively active Cdc42 (Cdc42V12) into neural stem cells, respectively. Overexpression of Cdc42N17 decreased both PLD activity and neurite outgrowth, whereas co-transfection with Cdc42N17 and PLD1 restored them. On the other hand, Cdc42V12 increased both PLD activity and neurite outgrowth, suggesting that active state of Cdc42 is important in upregulation of PLD activity which is responsible for the increase of neurite outgrowth

Effect of chondroitin sulfate proteoglycans on neuronal cell adhesion, spreading and neurite growth in culture

Directory of Open Access Journals (Sweden)

Jingyu Jin

2018-01-01

Full Text Available As one major component of extracellular matrix (ECM in the central nervous system, chondroitin sulfate proteoglycans (CSPGs have long been known as inhibitors enriched in the glial scar that prevent axon regeneration after injury. Although many studies have shown that CSPGs inhibited neurite outgrowth in vitro using different types of neurons, the mechanism by which CSPGs inhibit axonal growth remains poorly understood. Using cerebellar granule neuron (CGN culture, in this study, we evaluated the effects of different concentrations of both immobilized and soluble CSPGs on neuronal growth, including cell adhesion, spreading and neurite growth. Neurite length decreased while CSPGs concentration arised, meanwhile, a decrease in cell density accompanied by an increase in cell aggregates formation was observed. Soluble CSPGs also showed an inhibition on neurite outgrowth, but it required a higher concentration to induce cell aggregates formation than coated CSPGs. We also found that growth cone size was significantly reduced on CSPGs and neuronal cell spreading was restrained by CSPGs, attributing to an inhibition on lamellipodial extension. The effect of CSPGs on neuron adhesion was further evidenced by interference reflection microscopy (IRM which directly demonstrated that both CGNs and cerebral cortical neurons were more loosely adherent to a CSPG substrate. These data demonstrate that CSPGs have an effect on cell adhesion and spreading in addition to neurite outgrowth.

Inhibitory effects of brain-derived neurotrophic factor precursor on viability and neurite growth of murine hippocampal neurons

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Jia CHEN

2014-10-01

Full Text Available Objective　To explore the mediation effect of p75 neurotrophin receptor (p75NTR in the effect of brainderived neurotrophic factor precursor (proBDNF on viability and neurite growth of murine hippocampal neurons. Methods　 Hippocampal neurons were obtained from p75NTR+/+ and p75NTR-/- 18-day mice and primarily cultured. For p75NTR+/+ neurons, three experimental groups were set, i.e. control, proBDNF (30ng/ml, and proBDNF (30ng/ml+p75/Fc (30µg/ml groups. For p75NTR-/- neurons, two experimental groups were set, i.e. control and proBDNF (30ng/ml groups. MTT assays were performed after 24h to examine the viability of neonatal primary neurons. Immunofluorescent staining was conducted after 72h to investigate the neurite length. Results　With MAP2 and DAPI double fluorescent staining it was identified that the neonatal hippocampal neurons were successfully cultured in vitro with high purity. For viability assay of p75NTR+/+ neurons, it was found that the absorbance value at 570nm (A570 in proBDNF group was significantly lower than that in control group (P0.05. With neurite growth assay of p75NTR+/+ neurons, it was found that the neurite length in proBDNF group was significantly shorter than that in control group (P0.05. With neurite growth assay of p75NTR-/- neurons, no difference in neurite length was observed between proBDNF group and control group. Conclusion　proBDNF may inhibit the neuronal viability and neurite growth via p75NTR. DOI: 10.11855/j.issn.0577-7402.2014.09.03

Zebrafish diras1 Promoted Neurite Outgrowth in Neuro-2a Cells and Maintained Trigeminal Ganglion Neurons In Vivo via Rac1-Dependent Pathway.

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Yeh, Chi-Wei; Hsu, Li-Sung

2016-12-01

The small GTPase Ras superfamily regulates several neuronal functions including neurite outgrowth and neuron proliferation. In this study, zebrafish diras1a and diras1b were identified and were found to be mainly expressed in the central nervous system and dorsal neuron ganglion. Overexpression of green fluorescent protein (GFP)-diras1a or GFP-diras1b triggered neurite outgrowth of Neuro-2a cells. The wild types, but not the C terminus truncated forms, of diras1a and diras1b elevated the protein level of Ras-related C3 botulinum toxin substrate 1 (Rac1) and downregulated Ras homologous member A (RhoA) expression. Glutathione S-transferase (GST) pull-down assay also revealed that diras1a and diras1b enhanced Rac1 activity. Interfering with Rac1, Pak1, or cyclin-dependent kinase 5 (CDK5) activity or with the Arp2/3 inhibitor prevented diras1a and diras1b from mediating the neurite outgrowth effects. In the zebrafish model, knockdown of diras1a and/or diras1b by morpholino antisense oligonucleotides not only reduced axon guidance but also caused the loss of trigeminal ganglion without affecting the precursor markers, such as ngn1 and neuroD. Co-injection with messenger RNA (mRNA) derived from mouse diras1 or constitutively active human Rac1 restored the population of trigeminal ganglion. In conclusion, we provided preliminary evidence that diras1 is involved in neurite outgrowth and maintains the number of trigeminal ganglions through the Rac1-dependent pathway.

Nanotechnology versus stem cell engineering: in vitro comparison of neurite inductive potentials.

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Morano, Michela; Wrobel, Sandra; Fregnan, Federica; Ziv-Polat, Ofra; Shahar, Abraham; Ratzka, Andreas; Grothe, Claudia; Geuna, Stefano; Haastert-Talini, Kirsten

2014-01-01

Innovative nerve conduits for peripheral nerve reconstruction are needed in order to specifically support peripheral nerve regeneration (PNR) whenever nerve autotransplantation is not an option. Specific support of PNR could be achieved by neurotrophic factor delivery within the nerve conduits via nanotechnology or stem cell engineering and transplantation. Here, we comparatively investigated the bioactivity of selected neurotrophic factors conjugated to iron oxide nanoparticles (np-NTFs) and of bone marrow-derived stem cells genetically engineered to overexpress those neurotrophic factors (NTF-BMSCs). The neurite outgrowth inductive activity was monitored in culture systems of adult and neonatal rat sensory dorsal root ganglion neurons as well as in the cell line from rat pheochromocytoma (PC-12) cell sympathetic culture model system. We demonstrate that np-NTFs reliably support numeric neurite outgrowth in all utilized culture models. In some aspects, especially with regard to their long-term bioactivity, np-NTFs are even superior to free NTFs. Engineered NTF-BMSCs proved to be less effective in induction of sensory neurite outgrowth but demonstrated an increased bioactivity in the PC-12 cell culture system. In contrast, primary nontransfected BMSCs were as effective as np-NTFs in sensory neurite induction and demonstrated an impairment of neuronal differentiation in the PC-12 cell system. Our results evidence that nanotechnology as used in our setup is superior over stem cell engineering when it comes to in vitro models for PNR. Furthermore, np-NTFs can easily be suspended in regenerative hydrogel matrix and could be delivered that way to nerve conduits for future in vivo studies and medical application.

Mathematical Relationships between Neuron Morphology and Neurite Growth Dynamics in Drosophila melanogaster Larva Class IV Sensory Neurons

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Ganguly, Sujoy; Liang, Xin; Grace, Michael; Lee, Daniel; Howard, Jonathon

The morphology of neurons is diverse and reflects the diversity of neuronal functions, yet the principles that govern neuronal morphogenesis are unclear. In an effort to better understand neuronal morphogenesis we will be focusing on the development of the dendrites of class IV sensory neuron in Drosophila melanogaster. In particular we attempt to determine how the the total length, and the number of branches of dendrites are mathematically related to the dynamics of neurite growth and branching. By imaging class IV neurons during early embryogenesis we are able to measure the change in neurite length l (t) as a function of time v (t) = dl / dt . We found that the distribution of v (t) is well characterized by a hyperbolic secant distribution, and that the addition of new branches per unit time is well described by a Poisson process. Combining these measurements with the assumption that branching occurs with equal probability anywhere along the dendrite we were able to construct a mathematical model that provides reasonable agreement with the observed number of branches, and total length of the dendrites of the class IV sensory neuron.

Resveratrol Enhances Neurite Outgrowth and Synaptogenesis Via Sonic Hedgehog Signaling Following Oxygen-Glucose Deprivation/Reoxygenation Injury

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Fanren Tang

2017-09-01

Full Text Available Background/Aims: Neurite outgrowth and synaptogenesis are critical steps for functional recovery after stroke. Resveratrol promotes neurite outgrowth and synaptogenesis, but the underlying mechanism is not well understood, although the Sonic hedgehog (Shh signaling pathway may be involved. Given that resveratrol activates sirtuin (Sirt1, the present study examined whether this is mediated by Shh signaling. Methods: Primary cortical neuron cultures were pretreated with drugs before oxygen-glucose deprivation/reoxygenation (OGD/R. Cell viability and apoptosis were evaluated with Cell Counting Kit 8 and by terminal deoxynucleotidyl transferase dUTP nick end labeling, respectively. Neurite outgrowth and synaptogenesis were assessed by immunocytochemistry and western blotting, which was also used to examine the expression of Sirt1 and Shh signaling proteins. Results: Resveratrol and the Smoothened (Smo agonist purmophamine, which activates Shh signaling, increased viability, reduced apoptosis, and stimulated neurite outgrowth after OGD/R injury. Moreover, the expression of growth-associated protein(GAP-43, synaptophysin, Shh, Patched (Ptc-1, Smo, glioma-associated oncogene homolog (Gli-1, and Sirt1 were upregulated under these conditions. These effects were reversed by treatment with the Smo inhibitor cyclopamine, whereas the Sirt1 inhibitor sirtinol reduced the levels of Shh, Ptc-1, Smo, and Gli-1. Conclusions: Resveratrol reduces neuronal injury following OGD/R injury and enhances neurite outgrowth and synaptogenesis by activating Shh signaling, which in turn induces Sirt1.

Active learning of neuron morphology for accurate automated tracing of neurites

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Gala, Rohan; Chapeton, Julio; Jitesh, Jayant; Bhavsar, Chintan; Stepanyants, Armen

2014-01-01

Automating the process of neurite tracing from light microscopy stacks of images is essential for large-scale or high-throughput quantitative studies of neural circuits. While the general layout of labeled neurites can be captured by many automated tracing algorithms, it is often not possible to differentiate reliably between the processes belonging to different cells. The reason is that some neurites in the stack may appear broken due to imperfect labeling, while others may appear fused due to the limited resolution of optical microscopy. Trained neuroanatomists routinely resolve such topological ambiguities during manual tracing tasks by combining information about distances between branches, branch orientations, intensities, calibers, tortuosities, colors, as well as the presence of spines or boutons. Likewise, to evaluate different topological scenarios automatically, we developed a machine learning approach that combines many of the above mentioned features. A specifically designed confidence measure was used to actively train the algorithm during user-assisted tracing procedure. Active learning significantly reduces the training time and makes it possible to obtain less than 1% generalization error rates by providing few training examples. To evaluate the overall performance of the algorithm a number of image stacks were reconstructed automatically, as well as manually by several trained users, making it possible to compare the automated traces to the baseline inter-user variability. Several geometrical and topological features of the traces were selected for the comparisons. These features include the total trace length, the total numbers of branch and terminal points, the affinity of corresponding traces, and the distances between corresponding branch and terminal points. Our results show that when the density of labeled neurites is sufficiently low, automated traces are not significantly different from manual reconstructions obtained by trained users. PMID

Active learning of neuron morphology for accurate automated tracing of neurites

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Rohan eGala

2014-05-01

Full Text Available Automating the process of neurite tracing from light microscopy stacks of images is essential for large-scale or high-throughput quantitative studies of neural circuits. While the general layout of labeled neurites can be captured by many automated tracing algorithms, it is often not possible to differentiate reliably between the processes belonging to different cells. The reason is that some neurites in the stack may appear broken due to imperfect labeling, while others may appear fused due to the limited resolution of optical microscopy. Trained neuroanatomists routinely resolve such topological ambiguities during manual tracing tasks by combining information about distances between branches, branch orientations, intensities, calibers, tortuosities, colors, as well as the presence of spines or boutons. Likewise, to evaluate different topological scenarios automatically, we developed a machine learning approach that combines many of the above mentioned features. A specifically designed confidence measure was used to actively train the algorithm during user-assisted tracing procedure. Active learning significantly reduces the training time and makes it possible to obtain less than 1% generalization error rates by providing few training examples. To evaluate the overall performance of the algorithm a number of image stacks were reconstructed automatically, as well as manually by several trained users, making it possible to compare the automated traces to the baseline inter-user variability. Several geometrical and topological features of the traces were selected for the comparisons. These features include the total trace length, the total numbers of branch and terminal points, the affinity of corresponding traces, and the distances between corresponding branch and terminal points. Our results show that when the density of labeled neurites is sufficiently low, automated traces are not significantly different from manual reconstructions obtained by

Vital role of protein kinase C-related kinase (PRK1) in the formation and stability of neurites during hypoxia

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Thauerer, Bettina; zur Nedden, Stephanie; Baier-Bitterlich, Gabriele

2010-01-01

Exposure of pheochromocytoma (PC12) cells to hypoxia (1% O2) favors differentiation at the expense of cell viability. Additional incubation with nerve growth factor (NGF) and guanosine, a purine nucleoside with neurotrophin characteristics, rescued cell viability and further enhanced the extension of neurites. In parallel, an increase in the activity of protein kinase C-related kinase (PRK1), which is known to be involved in regulation of the actin cytoskeleton, was observed in hypoxic cells....

The Development of Self-Regulation across Early Childhood

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Montroy, Janelle J.; Bowles, Ryan P.; Skibbe, Lori E.; McClelland, Megan M.; Morrison, Frederick J.

2016-01-01

The development of early childhood self-regulation is often considered an early life marker for later life successes. Yet little longitudinal research has evaluated whether there are different trajectories of self-regulation development across children. This study investigates the development of behavioral self-regulation between the ages of 3 and…

Modeling extracellular electrical stimulation: I. Derivation and interpretation of neurite equations.

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Meffin, Hamish; Tahayori, Bahman; Grayden, David B; Burkitt, Anthony N

2012-12-01

Neuroprosthetic devices, such as cochlear and retinal implants, work by directly stimulating neurons with extracellular electrodes. This is commonly modeled using the cable equation with an applied extracellular voltage. In this paper a framework for modeling extracellular electrical stimulation is presented. To this end, a cylindrical neurite with confined extracellular space in the subthreshold regime is modeled in three-dimensional space. Through cylindrical harmonic expansion of Laplace's equation, we derive the spatio-temporal equations governing different modes of stimulation, referred to as longitudinal and transverse modes, under types of boundary conditions. The longitudinal mode is described by the well-known cable equation, however, the transverse modes are described by a novel ordinary differential equation. For the longitudinal mode, we find that different electrotonic length constants apply under the two different boundary conditions. Equations connecting current density to voltage boundary conditions are derived that are used to calculate the trans-impedance of the neurite-plus-thin-extracellular-sheath. A detailed explanation on depolarization mechanisms and the dominant current pathway under different modes of stimulation is provided. The analytic results derived here enable the estimation of a neurite's membrane potential under extracellular stimulation, hence bypassing the heavy computational cost of using numerical methods.

Diazinon and diazoxon impair the ability of astrocytes to foster neurite outgrowth in primary hippocampal neurons

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Pizzurro, Daniella M.; Dao, Khoi; Costa, Lucio G.

2014-01-01

Evidence from in vivo and epidemiological studies suggests that organophosphorus insecticides (OPs) are developmental neurotoxicants, but possible underlying mechanisms are still unclear. Astrocytes are increasingly recognized for their active role in normal neuronal development. This study sought to investigate whether the widely-used OP diazinon (DZ), and its oxygen metabolite diazoxon (DZO), would affect glial–neuronal interactions as a potential mechanism of developmental neurotoxicity. Specifically, we investigated the effects of DZ and DZO on the ability of astrocytes to foster neurite outgrowth in primary hippocampal neurons. The results show that both DZ and DZO adversely affect astrocyte function, resulting in inhibited neurite outgrowth in hippocampal neurons. This effect appears to be mediated by oxidative stress, as indicated by OP-induced increased reactive oxygen species production in astrocytes and prevention of neurite outgrowth inhibition by antioxidants. The concentrations of OPs were devoid of cytotoxicity, and cause limited acetylcholinesterase inhibition in astrocytes (18 and 25% for DZ and DZO, respectively). Among astrocytic neuritogenic factors, the most important one is the extracellular matrix protein fibronectin. DZ and DZO decreased levels of fibronectin in astrocytes, and this effect was also attenuated by antioxidants. Underscoring the importance of fibronectin in this context, adding exogenous fibronectin to the co-culture system successfully prevented inhibition of neurite outgrowth caused by DZ and DZO. These results indicate that DZ and DZO increase oxidative stress in astrocytes, and this in turn modulates astrocytic fibronectin, leading to impaired neurite outgrowth in hippocampal neurons. - Highlights: • DZ and DZO inhibit astrocyte-mediated neurite outgrowth in rat hippocampal neurons. • Oxidative stress is involved in inhibition of neuritogenesis by DZ and DZO. • DZ and DZO decrease expression of the neuritogenic

Diazinon and diazoxon impair the ability of astrocytes to foster neurite outgrowth in primary hippocampal neurons

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Pizzurro, Daniella M.; Dao, Khoi [Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA (United States); Costa, Lucio G. [Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA (United States); Department of Neuroscience, University of Parma, Parma (Italy)

2014-02-01

Evidence from in vivo and epidemiological studies suggests that organophosphorus insecticides (OPs) are developmental neurotoxicants, but possible underlying mechanisms are still unclear. Astrocytes are increasingly recognized for their active role in normal neuronal development. This study sought to investigate whether the widely-used OP diazinon (DZ), and its oxygen metabolite diazoxon (DZO), would affect glial–neuronal interactions as a potential mechanism of developmental neurotoxicity. Specifically, we investigated the effects of DZ and DZO on the ability of astrocytes to foster neurite outgrowth in primary hippocampal neurons. The results show that both DZ and DZO adversely affect astrocyte function, resulting in inhibited neurite outgrowth in hippocampal neurons. This effect appears to be mediated by oxidative stress, as indicated by OP-induced increased reactive oxygen species production in astrocytes and prevention of neurite outgrowth inhibition by antioxidants. The concentrations of OPs were devoid of cytotoxicity, and cause limited acetylcholinesterase inhibition in astrocytes (18 and 25% for DZ and DZO, respectively). Among astrocytic neuritogenic factors, the most important one is the extracellular matrix protein fibronectin. DZ and DZO decreased levels of fibronectin in astrocytes, and this effect was also attenuated by antioxidants. Underscoring the importance of fibronectin in this context, adding exogenous fibronectin to the co-culture system successfully prevented inhibition of neurite outgrowth caused by DZ and DZO. These results indicate that DZ and DZO increase oxidative stress in astrocytes, and this in turn modulates astrocytic fibronectin, leading to impaired neurite outgrowth in hippocampal neurons. - Highlights: • DZ and DZO inhibit astrocyte-mediated neurite outgrowth in rat hippocampal neurons. • Oxidative stress is involved in inhibition of neuritogenesis by DZ and DZO. • DZ and DZO decrease expression of the neuritogenic

Potentiation of nerve growth factor-induced neurite outgrowth in PC12 cells by ifenprodil: the role of sigma-1 and IP3 receptors.

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Tamaki Ishima

Full Text Available In addition to both the α1 adrenergic receptor and N-methyl-D-aspartate (NMDA receptor antagonists, ifenprodil binds to the sigma receptor subtypes 1 and 2. In this study, we examined the effects of ifenprodil on nerve growth factor (NGF-induced neurite outgrowth in PC12 cells. Ifenprodil significantly potentiated NGF-induced neurite outgrowth, in a concentration-dependent manner. In contrast, the α1 adrenergic receptor antagonist, prazosin and the NMDA receptor NR2B antagonist, Ro 25-6981 did not alter NGF-induced neurite outgrowth. Potentiation of NGF-induced neurite outgrowth mediated by ifenprodil was significantly antagonized by co-administration of the selective sigma-1 receptor antagonist, NE-100, but not the sigma-2 receptor antagonist, SM-21. Similarly, ifenprodil enhanced NGF-induced neurite outgrowth was again significantly reduced by the inositol 1,4,5-triphosphate (IP(3 receptor antagonists, xestospongin C and 2-aminoethoxydiphenyl borate (2-APB treatment. Furthermore, BAPTA-AM, a chelator of intracellular Ca(2+, blocked the effects of ifenprodil on NGF-induced neurite outgrowth, indicating the role of intracellular Ca(2+ in the neurite outgrowth. These findings suggest that activation at sigma-1 receptors and subsequent interaction with IP(3 receptors may mediate the pharmacological effects of ifenprodil on neurite outgrowth.

Ecdysone signaling regulates specification of neurons with a male-specific neurite in Drosophila

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Binglong Zhang

2018-02-01

Full Text Available Some mAL neurons in the male brain form the ipsilateral neurite (ILN[+] in a manner dependent on FruBM, a male-specific transcription factor. FruBM represses robo1 transcription, allowing the ILN to form. We found that the proportion of ILN[+]-mALs in all observed single cell clones dropped from ∼90% to ∼30% by changing the heat-shock timing for clone induction from 4-5 days after egg laying (AEL to 6-7 days AEL, suggesting that the ILN[+]-mALs are produced predominantly by young neuroblasts. Upon EcR-A knockdown, ILN[+]-mALs were produced at a high rate (∼60%, even when heat shocked at 6-7 days AEL, yet EcR-B1 knockdown reduced the proportion of ILN[+]-mALs to ∼30%. Immunoprecipitation assays in S2 cells demonstrated that EcR-A and EcR-B1 form a complex with FruBM. robo1 reporter transcription was repressed by FruBM and ecdysone counteracted FruBM. We suggest that ecdysone signaling modulates the FruBM action to produce an appropriate number of male-type neurons.

The inverse F-BAR domain protein srGAP2 acts through srGAP3 to modulate neuronal differentiation and neurite outgrowth of mouse neuroblastoma cells.

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Yue Ma

Full Text Available The inverse F-BAR (IF-BAR domain proteins srGAP1, srGAP2 and srGAP3 are implicated in neuronal development and may be linked to mental retardation, schizophrenia and seizure. A partially overlapping expression pattern and highly similar protein structures indicate a functional redundancy of srGAPs in neuronal development. Our previous study suggests that srGAP3 negatively regulates neuronal differentiation in a Rac1-dependent manner in mouse Neuro2a cells. Here we show that exogenously expressed srGAP1 and srGAP2 are sufficient to inhibit valporic acid (VPA-induced neurite initiation and growth in the mouse Neuro2a cells. While ectopic- or over-expression of RhoGAP-defective mutants, srGAP1(R542A and srGAP2(R527A exert a visible inhibitory effect on neuronal differentiation. Unexpectedly, knockdown of endogenous srGAP2 fails to facilitate the neuronal differentiation induced by VPA, but promotes neurite outgrowth of differentiated cells. All three IF-BAR domains from srGAP1-3 can induce filopodia formation in Neuro2a, but the isolated IF-BAR domain from srGAP2, not from srGAP1 and srGAP3, can promote VPA-induced neurite initiation and neuronal differentiation. We identify biochemical and functional interactions of the three srGAPs family members. We propose that srGAP3-Rac1 signaling may be required for the effect of srGAP1 and srGAP2 on attenuating neuronal differentiation. Furthermore, inhibition of Slit-Robo interaction can phenocopy a loss-of-function of srGAP3, indicating that srGAP3 may be dedicated to the Slit-Robo pathway. Our results demonstrate the interplay between srGAP1, srGAP2 and srGAP3 regulates neuronal differentiation and neurite outgrowth. These findings may provide us new insights into the possible roles of srGAPs in neuronal development and a potential mechanism for neurodevelopmental diseases.

Chlorpyrifos- and chlorpyrifos oxon-induced neurite retraction in pre-differentiated N2a cells is associated with transient hyperphosphorylation of neurofilament heavy chain and ERK 1/2

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Sindi, Ramya A.; Harris, Wayne; Arnott, Gordon; Flaskos, John; Lloyd Mills, Chris; Hargreaves, Alan J.

2016-01-01

Chlorpyrifos (CPF) and CPF-oxon (CPO) are known to inhibit neurite outgrowth but little is known about their ability to induce neurite retraction in differentiating neuronal cells. The aims of this study were to determine the ability of these compounds to destabilize neurites and to identify the key molecular events involved. N2a cells were induced to differentiate for 20 h before exposure to CPF or CPO for 2–8 h. Fixed cell monolayers labeled with carboxyfluorescein succinimidyl ester or immunofluorescently stained with antibodies to tubulin (B512) or phosphorylated neurofilament heavy chain (Ta51) showed time- and concentration-dependent reductions in numbers and length of axon-like processes compared to the control, respectively, retraction of neurites being observed within 2 h of exposure by live cell imaging. Neurofilament disruption was also observed in treated cells stained by indirect immunofluorescence with anti-phosphorylated neurofilament heavy chain (NFH) monoclonal antibody SMI34, while the microtubule network was unaffected. Western blotting analysis revealed transiently increased levels of reactivity of Ta51 after 2 h exposure and reduced levels of reactivity of the same antibody following 8 h treatment with both compounds, whereas reactivity with antibodies to anti-total NFH or anti-tubulin was not affected. The alteration in NFH phosphorylation at 2 h exposure was associated with increased activation of extracellular signal-regulated protein kinase ERK 1/2. However, increased levels of phosphatase activity were observed following 8 h exposure. These findings suggest for the first time that organophosphorothionate pesticide-induced neurite retraction in N2a cells is associated with transient increases in NFH phosphorylation and ERK1/2 activation. - Highlights: • Chlorpyrifos and chlorpyrifos oxon induced rapid neurite retraction in N2a cells. • This occurred following transient hyperphosphorylation of ERK 1/2. • It was concomitant with

Chlorpyrifos- and chlorpyrifos oxon-induced neurite retraction in pre-differentiated N2a cells is associated with transient hyperphosphorylation of neurofilament heavy chain and ERK 1/2

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Sindi, Ramya A., E-mail: ramya.sindi2010@my.ntu.ac.uk [Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom); School of Applied Medical Sciences, Umm Al-Qura University, Makkah (Saudi Arabia); Harris, Wayne [Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom); Arnott, Gordon [School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS (United Kingdom); Flaskos, John [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Lloyd Mills, Chris [School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS (United Kingdom); Hargreaves, Alan J., E-mail: alan.hargreaves@ntu.ac.uk [Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom)

2016-10-01

Chlorpyrifos (CPF) and CPF-oxon (CPO) are known to inhibit neurite outgrowth but little is known about their ability to induce neurite retraction in differentiating neuronal cells. The aims of this study were to determine the ability of these compounds to destabilize neurites and to identify the key molecular events involved. N2a cells were induced to differentiate for 20 h before exposure to CPF or CPO for 2–8 h. Fixed cell monolayers labeled with carboxyfluorescein succinimidyl ester or immunofluorescently stained with antibodies to tubulin (B512) or phosphorylated neurofilament heavy chain (Ta51) showed time- and concentration-dependent reductions in numbers and length of axon-like processes compared to the control, respectively, retraction of neurites being observed within 2 h of exposure by live cell imaging. Neurofilament disruption was also observed in treated cells stained by indirect immunofluorescence with anti-phosphorylated neurofilament heavy chain (NFH) monoclonal antibody SMI34, while the microtubule network was unaffected. Western blotting analysis revealed transiently increased levels of reactivity of Ta51 after 2 h exposure and reduced levels of reactivity of the same antibody following 8 h treatment with both compounds, whereas reactivity with antibodies to anti-total NFH or anti-tubulin was not affected. The alteration in NFH phosphorylation at 2 h exposure was associated with increased activation of extracellular signal-regulated protein kinase ERK 1/2. However, increased levels of phosphatase activity were observed following 8 h exposure. These findings suggest for the first time that organophosphorothionate pesticide-induced neurite retraction in N2a cells is associated with transient increases in NFH phosphorylation and ERK1/2 activation. - Highlights: • Chlorpyrifos and chlorpyrifos oxon induced rapid neurite retraction in N2a cells. • This occurred following transient hyperphosphorylation of ERK 1/2. • It was concomitant with

In vitro formation of the Merkel cell-neurite complex in embryonic mouse whiskers using organotypic co-cultures.

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Ishida, Kentaro; Saito, Tetsuichiro; Mitsui, Toshiyuki

2018-06-01

A Merkel cell-neurite complex is a touch receptor composed of specialized epithelial cells named Merkel cells and peripheral sensory nerves in the skin. Merkel cells are found in touch-sensitive skin components including whisker follicles. The nerve fibers that innervate Merkel cells of a whisker follicle extend from the maxillary branch of the trigeminal ganglion. Whiskers as a sensory organ attribute to the complicated architecture of the Merkel cell-neurite complex, and therefore it is intriguing how the structure is formed. However, observing the dynamic process of the formation of a Merkel cell-neurite complex in whiskers during embryonic development is still difficult. In this study, we tried to develop an organotypic co-culture method of a whisker pad and a trigeminal ganglion explant to form the Merkel cell-neurite complex in vitro. We initially developed two distinct culture methods of a single whisker row and a trigeminal ganglion explant, and then combined them. By dissecting and cultivating a single row from a whisker pad, the morphogenesis of whisker follicles could be observed under a microscope. After the co-cultivation of the whisker row with a trigeminal ganglion explant, a Merkel cell-neurite complex composed of Merkel cells, which were positive for both cytokeratin 8 and SOX2, Neurofilament-H-positive trigeminal nerve fibers and Schwann cells expressing Nestin, SOX2 and SOX10 was observed via immunohistochemical analyses. These results suggest that the process for the formation of a Merkel cell-neurite complex can be observed under a microscope using our organotypic co-culture method. © 2018 Japanese Society of Developmental Biologists.

Constitutive Overexpression of the Basic Helix-Loop-Helix Nex1/MATH-2 Transcription Factor Promotes Neuronal Differentiation of PC12 Cells and Neurite Regeneration

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Uittenbogaard, Martine; Chiaramello, Anne

2009-01-01

Elucidation of the intricate transcriptional pathways leading to neural differentiation and the establishment of neuronal identity is critical to the understanding and design of therapeutic approaches. Among the important players, the basic helix-loop-helix (bHLH) transcription factors have been found to be pivotal regulators of neurogenesis. In this study, we investigate the role of the bHLH differentiation factor Nex1/MATH-2 in conjunction with the nerve growth factor (NGF) signaling pathway using the rat phenochromocytoma PC12 cell line. We report that the expression of Nex1 protein is induced after 5 hr of NGF treatment and reaches maximal levels at 24 hr, when very few PC12 cells have begun extending neurites and ceased cell division. Furthermore, our study demonstrates that Nex1 has the ability to trigger neuronal differentiation of PC12 cells in the absence of neurotrophic factor. We show that Nex1 plays an important role in neurite outgrowth and has the capacity to regenerate neurite outgrowth in the absence of NGF. These results are corroborated by the fact that Nex1 targets a repertoire of distinct types of genes associated with neuronal differentiation, such as GAP-43, βIII-tubulin, and NeuroD. In addition, our findings show that Nex1 up-regulates the expression of the mitotic inhibitor p21WAF1, thus linking neuronal differentiation to cell cycle withdrawal. Finally, our studies show that overexpression of a Nex1 mutant has the ability to block the execution of NGF-induced differentiation program, suggesting that Nex1 may be an important effector of the NGF signaling pathway. PMID:11782967

Neurite outgrowth in human iPSC-derived neurons

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Data on morphology of rat and human neurons in cell cultureThis dataset is associated with the following publication:Druwe, I., T. Freudenrich , K. Wallace , T. Shafer , and W. Mundy. Comparison of Human Induced PluripotentStem Cell-Derived Neurons and Rat Primary CorticalNeurons as In Vitro Models of Neurite Outgrowth. Applied In vitro Toxicology. Mary Ann Liebert, Inc., Larchmont, NY, USA, 2(1): 26-36, (2016).

Neurite density imaging versus imaging of microscopic anisotropy in diffusion MRI: A model comparison using spherical tensor encoding.

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Lampinen, Björn; Szczepankiewicz, Filip; Mårtensson, Johan; van Westen, Danielle; Sundgren, Pia C; Nilsson, Markus

2017-02-15

In diffusion MRI (dMRI), microscopic diffusion anisotropy can be obscured by orientation dispersion. Separation of these properties is of high importance, since it could allow dMRI to non-invasively probe elongated structures such as neurites (axons and dendrites). However, conventional dMRI, based on single diffusion encoding (SDE), entangles microscopic anisotropy and orientation dispersion with intra-voxel variance in isotropic diffusivity. SDE-based methods for estimating microscopic anisotropy, such as the neurite orientation dispersion and density imaging (NODDI) method, must thus rely on model assumptions to disentangle these features. An alternative approach is to directly quantify microscopic anisotropy by the use of variable shape of the b-tensor. Along those lines, we here present the 'constrained diffusional variance decomposition' (CODIVIDE) method, which jointly analyzes data acquired with diffusion encoding applied in a single direction at a time (linear tensor encoding, LTE) and in all directions (spherical tensor encoding, STE). We then contrast the two approaches by comparing neurite density estimated using NODDI with microscopic anisotropy estimated using CODIVIDE. Data were acquired in healthy volunteers and in glioma patients. NODDI and CODIVIDE differed the most in gray matter and in gliomas, where NODDI detected a neurite fraction higher than expected from the level of microscopic diffusion anisotropy found with CODIVIDE. The discrepancies could be explained by the NODDI tortuosity assumption, which enforces a connection between the neurite density and the mean diffusivity of tissue. Our results suggest that this assumption is invalid, which leads to a NODDI neurite density that is inconsistent between LTE and STE data. Using simulations, we demonstrate that the NODDI assumptions result in parameter bias that precludes the use of NODDI to map neurite density. With CODIVIDE, we found high levels of microscopic anisotropy in white matter

Prenatal low-dose methylmercury exposure impairs neurite outgrowth and synaptic protein expression and suppresses TrkA pathway activity and eEF1A1 expression in the rat cerebellum

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Fujimura, Masatake, E-mail: fujimura@nimd.go.jp [Department of Basic Medical Sciences, National Institute for Minamata Disease, Kumamoto (Japan); Usuki, Fusako [Department of Clinical Medicine, National Institute for Minamata Disease, Kumamoto (Japan); Cheng, Jinping; Zhao, Wenchang [School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)

2016-05-01

Methylmercury (MeHg) is a highly neurotoxic environmental chemical that can cause developmental impairments. Human fetuses and neonates are particularly susceptible to MeHg toxicity; however, the mechanisms governing its effects in the developing brain are unclear. In the present study, we investigated the effects of prenatal and lactational MeHg exposure on the developing cerebellum in rats. We demonstrated that exposure to 5 ppm MeHg decreased postnatal expression of pre- and postsynaptic proteins, suggesting an impairment in synaptic development. MeHg exposure also reduced neurite outgrowth, as shown by a decrease in the expression of the neurite marker neurofilament H. These changes were not observed in rats exposed to 1 ppm MeHg. In order to define the underlying mechanism, we investigated the effects of MeHg exposure on the tropomyosin receptor kinase (Trk) A pathway, which plays important roles in neuronal differentiation and synapse formation. We demonstrated suppression of the TrkA pathway on gestation day 20 in rats exposed to 5 ppm MeHg. In addition, down-regulation of eukaryotic elongation factor 1A1 (eEF1A1) was observed on postnatal day 1. eEF1A1 knockdown in differentiating PC12 cells impaired neurite outgrowth and synaptic protein expression, similar to the results of MeHg exposure in the cerebellum. These results suggest that suppression of the TrkA pathway and subsequent decreases in eEF1A1 expression induced by prenatal exposure to MeHg may lead to reduced neurite outgrowth and synaptic protein expression in the developing cerebellum. - Highlights: • Prenatal exposure to MeHg decreased postnatal expression of synaptic proteins. • MeHg exposure also reduced neurite outgrowth postnatally. • Suppression of the TrkA pathway and eEF1A1 expression was induced by MeHg exposure. • eEF1A1 knockdown impaired neurite outgrowth and synaptic protein expression.

Prenatal low-dose methylmercury exposure impairs neurite outgrowth and synaptic protein expression and suppresses TrkA pathway activity and eEF1A1 expression in the rat cerebellum

International Nuclear Information System (INIS)

Fujimura, Masatake; Usuki, Fusako; Cheng, Jinping; Zhao, Wenchang

2016-01-01

Methylmercury (MeHg) is a highly neurotoxic environmental chemical that can cause developmental impairments. Human fetuses and neonates are particularly susceptible to MeHg toxicity; however, the mechanisms governing its effects in the developing brain are unclear. In the present study, we investigated the effects of prenatal and lactational MeHg exposure on the developing cerebellum in rats. We demonstrated that exposure to 5 ppm MeHg decreased postnatal expression of pre- and postsynaptic proteins, suggesting an impairment in synaptic development. MeHg exposure also reduced neurite outgrowth, as shown by a decrease in the expression of the neurite marker neurofilament H. These changes were not observed in rats exposed to 1 ppm MeHg. In order to define the underlying mechanism, we investigated the effects of MeHg exposure on the tropomyosin receptor kinase (Trk) A pathway, which plays important roles in neuronal differentiation and synapse formation. We demonstrated suppression of the TrkA pathway on gestation day 20 in rats exposed to 5 ppm MeHg. In addition, down-regulation of eukaryotic elongation factor 1A1 (eEF1A1) was observed on postnatal day 1. eEF1A1 knockdown in differentiating PC12 cells impaired neurite outgrowth and synaptic protein expression, similar to the results of MeHg exposure in the cerebellum. These results suggest that suppression of the TrkA pathway and subsequent decreases in eEF1A1 expression induced by prenatal exposure to MeHg may lead to reduced neurite outgrowth and synaptic protein expression in the developing cerebellum. - Highlights: • Prenatal exposure to MeHg decreased postnatal expression of synaptic proteins. • MeHg exposure also reduced neurite outgrowth postnatally. • Suppression of the TrkA pathway and eEF1A1 expression was induced by MeHg exposure. • eEF1A1 knockdown impaired neurite outgrowth and synaptic protein expression.

Nanotechnology versus stem cell engineering: in vitro comparison of neurite inductive potentials

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Morano M

2014-11-01

Full Text Available Michela Morano,1,* Sandra Wrobel,2,3,* Federica Fregnan,1 Ofra Ziv-Polat,4 Abraham Shahar,4 Andreas Ratzka,2 Claudia Grothe,2,3 Stefano Geuna,1 Kirsten Haastert-Talini2,3 1Department of Clinical and Biological Sciences, Università Degli Studi di Torino, Orbassano, Piemonte, Italy; 2Institute of Neuroanatomy, Hannover Medical School, Hannover, Lower-Saxony, Germany; 3Center for Systems Neuroscience (ZSN, Hannover, Lower-Saxony, Germany; 4NVR Research Ltd, Ness-Ziona, Israel *These authors contributed equally to this work and share first authorship Purpose: Innovative nerve conduits for peripheral nerve reconstruction are needed in order to specifically support peripheral nerve regeneration (PNR whenever nerve autotransplantation is not an option. Specific support of PNR could be achieved by neurotrophic factor delivery within the nerve conduits via nanotechnology or stem cell engineering and transplantation.Methods: Here, we comparatively investigated the bioactivity of selected neurotrophic factors conjugated to iron oxide nanoparticles (np-NTFs and of bone marrow-derived stem cells genetically engineered to overexpress those neurotrophic factors (NTF-BMSCs. The neurite outgrowth inductive activity was monitored in culture systems of adult and neonatal rat sensory dorsal root ganglion neurons as well as in the cell line from rat pheochromocytoma (PC-12 cell sympathetic culture model system.Results: We demonstrate that np-NTFs reliably support numeric neurite outgrowth in all utilized culture models. In some aspects, especially with regard to their long-term bioactivity, np-NTFs are even superior to free NTFs. Engineered NTF-BMSCs proved to be less effective in induction of sensory neurite outgrowth but demonstrated an increased bioactivity in the PC-12 cell culture system. In contrast, primary nontransfected BMSCs were as effective as np-NTFs in sensory neurite induction and demonstrated an impairment of neuronal differentiation in the PC-12�

Low-Intensity Pulsed Ultrasound Enhances Nerve Growth Factor-Induced Neurite Outgrowth through Mechanotransduction-Mediated ERK1/2-CREB-Trx-1 Signaling.

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Zhao, Lu; Feng, Yi; Hu, Hong; Shi, Aiwei; Zhang, Lei; Wan, Mingxi

2016-12-01

Enhancing the action of nerve growth factor (NGF) is a potential therapeutic approach to neural regeneration. To facilitate neural regeneration, we investigated whether combining low-intensity pulsed ultrasound (LIPUS) and NGF could promote neurite outgrowth, an essential process in neural regeneration. In the present study, PC12 cells were subjected to a combination of LIPUS (1 MHz, 30 or 50 mW/cm 2 , 20% duty cycle and 100-Hz pulse repetition frequency, 10 min every other day) and NGF (50 ng/mL) treatment, and then neurite outgrowth was compared. Our findings indicated that the combined treatment with LIPUS (50 mW/cm 2 ) and NGF (50 ng/mL) promotes neurite outgrowth that is comparable to that achieved by NGF (100 ng/mL) treatment alone. LIPUS significantly increased NGF-induced neurite length, but not neurite branching. These effects were attributed to the enhancing effects of LIPUS on NGF-induced phosphorylation of ERK1/2 and CREB and the expression of thioredoxin (Trx-1). Furthermore, blockage of stretch-activated ion channels with Gd 3+ suppressed the stimulating effects of LIPUS on NGF-induced neurite outgrowth and the downstream signaling activation. Taken together, our findings suggest that LIPUS enhances NGF-induced neurite outgrowth through mechanotransduction-mediated signaling of the ERK1/2-CREB-Trx-1 pathway. The combination of LIPUS and NGF could potentially be used for the treatment of nerve injury and neurodegenerative diseases. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Navigating neurites utilize cellular topography of Schwann cell somas and processes for optimal guidance

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Lopez-Fagundo, Cristina; Mitchel, Jennifer A.; Ramchal, Talisha D.; Dingle, Yu-Ting L.; Hoffman-Kim, Diane

2013-01-01

The path created by aligned Schwann cells (SCs) after nerve injury underlies peripheral nerve regeneration. We developed geometric bioinspired substrates to extract key information needed for axon guidance by deconstructing the topographical cues presented by SCs. We have previously reported materials that directly replicate SC topography with micro- and nanoscale resolution, but a detailed explanation of the means of directed axon extension on SC topography has not yet been described. Here, using neurite tracing and time-lapse microscopy, we analyzed the SC features that influence axon guidance. Novel poly(dimethylsiloxane) materials, fabricated via photolithography, incorporated bioinspired topographical components with the shapes and sizes of aligned SCs, namely somas and processes, where the length of the processes were varied but the soma geometry and dimensions were kept constant. Rat dorsal root ganglia neurites aligned to all materials presenting bioinspired topography after a 5 days in culture and to bioinspired materials presenting soma and process features after only 17 hours in culture. Key findings of this study were: Neurite response to underlying bioinspired topographical features was time dependent, where at 5 days, neurites aligned most strongly to materials presenting combinations of soma and process features, with higher than average density of either process or soma features; but at 17 hours they aligned more strongly to materials presenting average densities of soma and process features and to materials presenting process features only. These studies elucidate the influence of SC topography on axon guidance in a time-dependent setting and have implications for the optimization of nerve regeneration strategies. PMID:23557939

Pleurotus giganteus (Berk.) Karunarathna & K.D. Hyde: Nutritional value and in vitro neurite outgrowth activity in rat pheochromocytoma cells.

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Phan, Chia-Wei; Wong, Wei-Lun; David, Pamela; Naidu, Murali; Sabaratnam, Vikineswary

2012-07-19

Drugs dedicated to alleviate neurodegenerative diseases like Parkinson's and Alzheimer's have always been associated with debilitating side effects. Medicinal mushrooms which harness neuropharmacological compounds offer a potential possibility for protection against such diseases. Pleurotus giganteus (formerly known as Panus giganteus) has been consumed by the indigenous people in Peninsular Malaysia for many years. Domestication of this wild mushroom is gaining popularity but to our knowledge, medicinal properties reported for this culinary mushroom are minimal. The fruiting bodies P. giganteus were analysed for its nutritional values. Cytotoxicity of the mushroom's aqueous and ethanolic extracts towards PC12, a rat pheochromocytoma cell line was assessed by using 3-[4,5-dimethythiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Neurite outgrowth stimulation assay was carried out with nerve growth factor (NGF) as control. To elucidate signaling mechanisms involved by mushroom extract-induced neurite outgrowth, treatment of specific inhibitor for MEK/ERK and PI3K signalling pathway was carried out. The fruiting bodies of P. giganteus were found to have high carbohydrate, dietary fibre, potassium, phenolic compounds and triterpenoids. Both aqueous and ethanolic extracts induced neurite outgrowth of PC12 cells in a dose- and time-dependant manner with no detectable cytotoxic effect. At day 3, 25 μg/ml of aqueous extract and 15 μg/ml of ethanolic extract showed the highest percentage of neurite-bearing cells, i.e. 31.7 ± 1.1% and 33.3 ± 0.9%; respectively. Inhibition treatment results suggested that MEK/ERK and PI3K/Akt are responsible for neurite outgrowth of PC12 cells stimulated by P. giganteus extract. The high potassium content (1345.7 mg/100 g) may be responsible for promoting neurite extension, too. P. giganteus contains bioactive compounds that mimic NGF and are responsible for neurite stimulation. Hence, this mushroom may be

A role for complexes of survival of motor neurons (SMN) protein with gemins and profilin in neurite-like cytoplasmic extensions of cultured nerve cells

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Sharma, Aarti; Lambrechts, Anja; Le thi Hao; Le, Thanh T.; Sewry, Caroline A.; Ampe, Christophe; Burghes, Arthur H.M.; Morris, Glenn E.

2005-01-01

Spinal muscular atrophy (SMA) is caused by reduced levels of SMN (survival of motor neurons protein) and consequent loss of motor neurons. SMN is involved in snRNP transport and nuclear RNA splicing, but axonal transport of SMN has also been shown to occur in motor neurons. SMN also binds to the small actin-binding protein, profilin. We now show that SMN and profilin II co-localise in the cytoplasm of differentiating rat PC12 cells and in neurite-like extensions, especially at their growth cones. Many components of known SMN complexes were also found in these extensions, including gemin2 (SIP-1), gemin6, gemin7 and unrip (unr-interacting protein). Coilin p80 and Sm core protein immunoreactivity, however, were seen only in the nucleus. SMN is known to associate with β-actin mRNA and specific hnRNPs in axons and in neurite extensions of cultured nerve cells, and SMN also stimulates neurite outgrowth in cultures. Our results are therefore consistent with SMN complexes, rather than SMN alone, being involved in the transport of actin mRNPs along the axon as in the transport of snRNPs into the nucleus by similar SMN complexes. Antisense knockdown of profilin I and II isoforms inhibited neurite outgrowth of PC12 cells and caused accumulation of SMN and its associated proteins in cytoplasmic aggregates. BIAcore studies demonstrated a high affinity interaction of SMN with profilin IIa, the isoform present in developing neurons. Pathogenic missense mutations in SMN, or deletion of exons 5 and 7, prevented this interaction. The interaction is functional in that SMN can modulate actin polymerisation in vitro by reducing the inhibitory effect of profilin IIa. This suggests that reduced SMN in SMA might cause axonal pathfinding defects by disturbing the normal regulation of microfilament growth by profilins

Electric field-induced astrocyte alignment directs neurite outgrowth

OpenAIRE

ALEXANDER, JOHN K.; FUSS, BABETTE; COLELLO, RAYMOND J.

2006-01-01

The extension and directionality of neurite outgrowth are key to achieving successful target connections during both CNS development and during the re-establishment of connections lost after neural trauma. The degree of axonal elongation depends, in large part, on the spatial arrangement of astrocytic processes rich in growth-promoting proteins. Because astrocytes in culture align their processes on exposure to an electrical field of physiological strength, we sought to determine the extent t...

7, 8, 3′-Trihydroxyflavone Promotes Neurite Outgrowth and Protects Against Bupivacaine-Induced Neurotoxicity in Mouse Dorsal Root Ganglion Neurons

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Shi, Haohong; Luo, Xingjing

2016-01-01

Background 7, 8, 3′-trihydroxyflavone (THF) is a novel pro-neuronal small molecule that acts as a TrkB agonist. In this study, we examined the effect of THF on promoting neuronal growth and protecting anesthetics-induced neurotoxicity in dorsal root ganglion (DRG) neurons in vitro. Material/Methods Neonatal mouse DRG neurons were cultured in vitro and treated with various concentrations of THF. The effect of THF on neuronal growth was investigated by neurite outgrowth assay and Western blot. In addition, the protective effects of THF on bupivacaine-induced neurotoxicity were investigated by apoptosis TUNEL assay, neurite outgrowth assay, and Western blot, respectively. Results THF promoted neurite outgrowth of DRG neurons in dose-dependent manner, with an EC50 concentration of 67.4 nM. Western blot analysis showed THF activated TrkB signaling pathway by inducing TrkB phosphorylation. THF also rescued bupivacaine-induced neurotoxicity by reducing apoptosis and protecting neurite retraction in DRG neurons. Furthermore, the protection of THF in bupivacaine-injured neurotoxicity was directly associated with TrkB phosphorylation in a concentration-dependent manner in DRG neurons. Conclusions THF has pro-neuronal effect on DRG neurons by promoting neurite growth and protecting against bupivacaine-induced neurotoxicity, likely through TrkB activation. PMID:27371503

Emotional and attentional predictors of self-regulation in early childhood

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Stępień-Nycz Małgorzata

2015-09-01

Full Text Available The development of self-regulation in early childhood is related to development of emotional regulation and attention, in particular executive attention (Feldman, 2009; Posner & Rothbart, 1998. As the ability to self-regulate is crucial in life (Casey et al., 2011, it is important to reveal early predictors of self-regulation. The aim of the paper is to present the results of longitudinal studies on the relationships between the functioning of attention, regulation of emotion and later self-regulatory abilities. 310 children were assessed at three time points. At 12 months of age emotional regulation in situation of frustration and attention regulation were assessed. At 18 and 24 months behavioral-emotional regulation in the Snack Delay Task was measured. Additionally parents assessed executive attention using The Early Childhood Behavior Questionnaire when children were 26 months old. Structural equation modelling revealed two different paths to development of self-regulatory abilities at 18 months: emotional (reactive system and emotionalattentional and only one emotional-attentional path at 24 months. The early ability to focus attention and later executive attention functioning revealed to be important predictors of self-regulatory abilities both at 18 and 24 months of age.

Neurite outgrowth mediated by translation elongation factor eEF1A1: a target for antiplatelet agent cilostazol.

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Kenji Hashimoto

Full Text Available Cilostazol, a type-3 phosphodiesterase (PDE3 inhibitor, has become widely used as an antiplatelet drug worldwide. A recent second Cilostazol Stroke Prevention Study demonstrated that cilostazol is superior to aspirin for prevention of stroke after an ischemic stroke. However, its precise mechanisms of action remain to be determined. Here, we report that cilostazol, but not the PDE3 inhibitors cilostamide and milrinone, significantly potentiated nerve growth factor (NGF-induced neurite outgrowth in PC12 cells. Furthermore, specific inhibitors for the endoplasmic reticulum protein inositol 1,4,5-triphosphate (IP(3 receptors and several common signaling pathways (PLC-γ, PI3K, Akt, p38 MAPK, and c-Jun N-terminal kinase (JNK, and the Ras/Raf/ERK/MAPK significantly blocked the potentiation of NGF-induced neurite outgrowth by cilostazol. Using a proteomics analysis, we identified that levels of eukaryotic translation elongation factor eEF1A1 protein were significantly increased by treatment with cilostazol, but not cilostamide, in PC12 cells. Moreover, the potentiating effects of cilostazol on NGF-induced neurite outgrowth were significantly antagonized by treatment with eEF1A1 RNAi, but not the negative control of eEF1A1. These findings suggest that eEF1A1 and several common cellular signaling pathways might play a role in the mechanism of cilostazol-induced neurite outgrowth. Therefore, agents that can increase the eEF1A1 protein may have therapeutic relevance in diverse conditions with altered neurite outgrowth.

Large enhancement in neurite outgrowth on a cell membrane-mimicking conducting polymer

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Zhu, Bo; Luo, Shyh-Chyang; Zhao, Haichao; Lin, Hsing-An; Sekine, Jun; Nakao, Aiko; Chen, Chi; Yamashita, Yoshiro; Yu, Hsiao-Hua

2014-07-01

Although electrically stimulated neurite outgrowth on bioelectronic devices is a promising means of nerve regeneration, immunogenic scar formation can insulate electrodes from targeted cells and tissues, thereby reducing the lifetime of the device. Ideally, an electrode material capable of electrically interfacing with neurons selectively and efficiently would be integrated without being recognized by the immune system and minimize its response. Here we develop a cell membrane-mimicking conducting polymer possessing several attractive features. This polymer displays high resistance towards nonspecific enzyme/cell binding and recognizes targeted cells specifically to allow intimate electrical communication over long periods of time. Its low electrical impedance relays electrical signals efficiently. This material is capable to integrate biochemical and electrical stimulation to promote neural cellular behaviour. Neurite outgrowth is enhanced greatly on this new conducting polymer; in addition, electrically stimulated secretion of proteins from primary Schwann cells can also occur on it.

Effects of a synthetic bioactive peptide on neurite growth and nerve growth factor release in chondroitin sulfate hydrogels

OpenAIRE

Conovaloff, Aaron W.; Beier, Brooke L.; Irazoqui, Pedro P.; Panitch, Alyssa

2011-01-01

Previous work has revealed robust dorsal root ganglia neurite growth in hydrogels of chondroitin sulfate. In the current work, it was determined whether addition of a synthetic bioactive peptide could augment neurite growth in these matrices via enhanced binding and sequestering of growth factors. Fluorescence recovery after photobleaching studies revealed that addition of peptide slowed nerve growth factor diffusivity in chondroitin sulfate gels, but not in control gels of hyaluronic acid. F...

Extracellular Nm23H1 stimulates neurite outgrowth from dorsal root ganglia neurons in vitro independently of nerve growth factor supplementation or its nucleoside diphosphate kinase activity

International Nuclear Information System (INIS)

Wright, K.T.; Seabright, R.; Logan, A.; Lilly, A.J.; Khanim, F.; Bunce, C.M.; Johnson, W.E.B.

2010-01-01

Research highlights: → Extracellular Nm23H1 stimulates nerve growth. → Extracellular Nm23H1 provides pathfinding cues to growth cones. → The neurotrophic activity of Nm23H1 is independent of NDP kinase activity. → The neurotrophic activity of Nm23H1 is independent of NGF. -- Abstract: The nucleoside diphosphate (NDP) kinase, Nm23H1, is a highly expressed during neuronal development, whilst induced over-expression in neuronal cells results in increased neurite outgrowth. Extracellular Nm23H1 affects the survival, proliferation and differentiation of non-neuronal cells. Therefore, this study has examined whether extracellular Nm23H1 regulates nerve growth. We have immobilised recombinant Nm23H1 proteins to defined locations of culture plates, which were then seeded with explants of embryonic chick dorsal root ganglia (DRG) or dissociated adult rat DRG neurons. The substratum-bound extracellular Nm23H1 was stimulatory for neurite outgrowth from chick DRG explants in a concentration-dependent manner. On high concentrations of Nm23H1, chick DRG neurite outgrowth was extensive and effectively limited to the location of the Nm23H1, i.e. neuronal growth cones turned away from adjacent collagen-coated substrata. Nm23H1-coated substrata also significantly enhanced rat DRG neuronal cell adhesion and neurite outgrowth in comparison to collagen-coated substrata. These effects were independent of NGF supplementation. Recombinant Nm23H1 (H118F), which does not possess NDP kinase activity, exhibited the same activity as the wild-type protein. Hence, a novel neuro-stimulatory activity for extracellular Nm23H1 has been identified in vitro, which may function in developing neuronal systems.

Extracellular Nm23H1 stimulates neurite outgrowth from dorsal root ganglia neurons in vitro independently of nerve growth factor supplementation or its nucleoside diphosphate kinase activity

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Wright, K.T. [Keele University at the RJAH Orthopaedic Hospital, Oswestry, Shropshire (United Kingdom); Seabright, R.; Logan, A. [Neuropharmacology and Neurobiology, School of Clinical and Experimental Medicine, Birmingham University, Birmingham (United Kingdom); Lilly, A.J.; Khanim, F.; Bunce, C.M. [Biosciences, Birmingham University, Birmingham (United Kingdom); Johnson, W.E.B., E-mail: w.e.johnson@aston.ac.uk [Life and Health Sciences, Aston University, Birmingham (United Kingdom)

2010-07-16

Research highlights: {yields} Extracellular Nm23H1 stimulates nerve growth. {yields} Extracellular Nm23H1 provides pathfinding cues to growth cones. {yields} The neurotrophic activity of Nm23H1 is independent of NDP kinase activity. {yields} The neurotrophic activity of Nm23H1 is independent of NGF. -- Abstract: The nucleoside diphosphate (NDP) kinase, Nm23H1, is a highly expressed during neuronal development, whilst induced over-expression in neuronal cells results in increased neurite outgrowth. Extracellular Nm23H1 affects the survival, proliferation and differentiation of non-neuronal cells. Therefore, this study has examined whether extracellular Nm23H1 regulates nerve growth. We have immobilised recombinant Nm23H1 proteins to defined locations of culture plates, which were then seeded with explants of embryonic chick dorsal root ganglia (DRG) or dissociated adult rat DRG neurons. The substratum-bound extracellular Nm23H1 was stimulatory for neurite outgrowth from chick DRG explants in a concentration-dependent manner. On high concentrations of Nm23H1, chick DRG neurite outgrowth was extensive and effectively limited to the location of the Nm23H1, i.e. neuronal growth cones turned away from adjacent collagen-coated substrata. Nm23H1-coated substrata also significantly enhanced rat DRG neuronal cell adhesion and neurite outgrowth in comparison to collagen-coated substrata. These effects were independent of NGF supplementation. Recombinant Nm23H1 (H118F), which does not possess NDP kinase activity, exhibited the same activity as the wild-type protein. Hence, a novel neuro-stimulatory activity for extracellular Nm23H1 has been identified in vitro, which may function in developing neuronal systems.

Regulated expression of the neural cell adhesion molecule L1 by specific patterns of neural impulses.

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Itoh, K; Stevens, B; Schachner, M; Fields, R D

1995-11-24

Development of the mammalian nervous system is regulated by neural impulse activity, but the molecular mechanisms are not well understood. If cell recognition molecules [for example, L1 and the neural cell adhesion molecule (NCAM)] were influenced by specific patterns of impulse activity, cell-cell interactions controlling nervous system structure could be regulated by nervous system function at critical stages of development. Low-frequency electrical pulses delivered to mouse sensory neurons in culture (0.1 hertz for 5 days) down-regulated expression of L1 messenger RNA and protein (but not NCAM). Fasciculation of neurites, adhesion of neuroblastoma cells, and the number of Schwann cells on neurites was reduced after 0.1-hertz stimulation, but higher frequencies or stimulation after synaptogenesis were without effect.

Neurite regeneration in adult rat retinas exposed to advanced glycation end-products and regenerative effects of neurotrophin-4.

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Bikbova, Guzel; Oshitari, Toshiyuki; Yamamoto, Shuichi

2013-10-09

The purpose of this study was to determine the effect of low concentrations of advanced glycation end-products on neurite regeneration in isolated rat retinas, and to determine the effects of neurotrophin-4 on regeneration in advanced glycation end-products exposed retinas. Retinal explants of 4 adult Sprague-Dawley rats were cultured on collagen gel and were incubated in; (1) serum-free control culture media, (2) glucose-advanced glycation end-products-bovine serum albumin media, (3) glycolaldehyde-advanced glycation end-products-bovine serum albumin media, (4) glyceraldehyde-advanced glycation end-products-bovine serum albumin media, (5) glucose-advanced glycation end-products+neurotrophin-4 media, (6) glycolaldehyde-advanced glycation end-products+neurotrophin-4 media, or (7) glyceraldehyde-advanced glycation end-products+neurotrophin-4 supplemented culture media. After 7 days, the number of regenerating neurites from the explants was counted. Then, explants were fixed, cryosectioned, and stained for TUNEL. The ratio of TUNEL-positive cells to all cells in the ganglion cell layer was determined. Immunohistochemical examinations for the active-form of caspase-9 and apoptosis-inducing factor were performed. In retinas incubated with advanced glycation end-products containing media, the number of regenerating neurites were fewer than in retinas without advanced glycation end-products, and the number of TUNEL-positive cells and caspase-9- and apoptosis-inducing factor-immunopositive cells was significantly higher than in control media. Neurotrophin-4 supplementation increased the numbers of regenerating neuritis, and the number of TUNEL-positives, caspase-9-, and apoptosis-inducing factor-immunopositive cells were significantly fewer than that in advanced glycation end-products without neurotrophin-4 media. Low doses of advanced glycation end-products impede neurite regeneration in the rat retinas. Neurotrophin-4 significantly enhances neurite regeneration in

Regulator of G protein signaling 5 (RGS5) inhibits sonic hedgehog function in mouse cortical neurons.

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Liu, Chuanliang; Hu, Qiongqiong; Jing, Jia; Zhang, Yun; Jin, Jing; Zhang, Liulei; Mu, Lili; Liu, Yumei; Sun, Bo; Zhang, Tongshuai; Kong, Qingfei; Wang, Guangyou; Wang, Dandan; Zhang, Yao; Liu, Xijun; Zhao, Wei; Wang, Jinghua; Feng, Tao; Li, Hulun

2017-09-01

Regulator of G protein signaling 5 (RGS5) acts as a GTPase-activating protein (GAP) for the Gαi subunit and negatively regulates G protein-coupled receptor signaling. However, its presence and function in postmitotic differentiated primary neurons remains largely uncharacterized. During neural development, sonic hedgehog (Shh) signaling is involved in cell signaling pathways via Gαi activity. In particular, Shh signaling is essential for embryonic neural tube patterning, which has been implicated in neuronal polarization involving neurite outgrowth. Here, we examined whether RGS5 regulates Shh signaling in neurons. RGS5 transcripts were found to be expressed in cortical neurons and their expression gradually declined in a time-dependent manner in culture system. When an adenovirus expressing RGS5 was introduced into an in vitro cell culture model of cortical neurons, RGS5 overexpression significantly reduced neurite outgrowth and FM4-64 uptake, while cAMP-PKA signaling was also affected. These findings suggest that RGS5 inhibits Shh function during neurite outgrowth and the presynaptic terminals of primary cortical neurons mature via modulation of cAMP. Copyright © 2017 Elsevier Inc. All rights reserved.

Early Self-Regulation, Early Self-Regulatory Change, and Their Longitudinal Relations to Adolescents' Academic, Health, and Mental Well-Being Outcomes.

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Howard, Steven J; Williams, Kate E

2018-05-16

To evaluate the extent to which early self-regulation and early changes in self-regulation are associated with adolescents' academic, health, and mental well-being outcomes. Data were collected from 1 of the cohorts in a large dual-cohort cross-sequential study of Australian children. This cohort consisted of a nationally representative data set of 4983 Australian children assessed at 4 to 5 years of age, who were followed longitudinally to 14 to 15 years of age. Using regression within a path analysis framework, we first sought to investigate associations of early self-regulation (at 4-5 years and 6-7 years of age) with a broad range of academic, health, and mental well-being outcomes in adolescence (at 14-15 years). We next investigated the extent to which an early change in self-regulation (from 4 to 7 years of age) predicted these adolescents' outcomes. Early self-regulation predicted the full range of adolescents' outcomes considered such that a 1-SD increase in self-regulation problems was associated with a 1.5- to 2.5-times greater risk of more-negative outcomes. An early positive change in self-regulation was associated with a reduced risk of these negative outcomes for 11 of the 13 outcomes considered. These results suggest the potential of early self-regulation interventions, in particular, in influencing long-term academic, health, and well-being trajectories.

Neurite outgrowth stimulatory effects of myco synthesized AuNPs from Hericium erinaceus (Bull.: Fr.) Pers. on pheochromocytoma (PC-12) cells.

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Raman, Jegadeesh; Lakshmanan, Hariprasath; John, Priscilla A; Zhijian, Chan; Periasamy, Vengadesh; David, Pamela; Naidu, Murali; Sabaratnam, Vikineswary

2015-01-01

Hericium erinaceus has been reported to have a wide range of medicinal properties such as stimulation of neurite outgrowth, promotion of functional recovery of axonotmetic peroneal nerve injury, antioxidant, antihypertensive, and antidiabetic properties. In recent years, the green synthesis of gold nanoparticles (AuNPs) has attracted intense interest due to the potential use in biomedical applications. The aim of this study was to investigate the effects of AuNPs from aqueous extract of H. erinaceus on neurite outgrowth of rat pheochromocytoma (PC-12) cells. The formation of AuNPs was characterized by UV-visible spectrum, energy dispersive X-ray (EDX), field-emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), particle size distribution, and Fourier transform-infrared spectroscopy (FTIR). Furthermore, the neurite extension study of synthesized AuNPs was evaluated by in vitro assay. The AuNPs exhibited maximum absorbance between 510 and 600 nm in UV-visible spectrum. FESEM and TEM images showed the existence of nanoparticles with sizes of 20-40 nm. FTIR measurements were carried out to identify the possible biomolecules responsible for capping and efficient stabilization of the nanoparticles. The purity and the crystalline properties were confirmed by EDX diffraction analysis, which showed strong signals with energy peaks in the range of 2-2.4 keV, indicating the existence of gold atoms. The synthesized AuNPs showed significant neurite extension on PC-12 cells. Nerve growth factor 50 ng/mL was used as a positive control. Treatment with different concentrations (nanograms) of AuNPs resulted in neuronal differentiation and neuronal elongation. AuNPs induced maximum neurite outgrowth of 13% at 600 ng/mL concentration. In this study, the AuNPs synthesis was achieved by a simple, low-cost, and rapid bioreduction approach. AuNPs were shown to have potential neuronal differentiation and stimulated neurite outgrowth. The water

Spontaneous Age-Related Neurite Branching in C. elegans

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Tank, Elizabeth M. H.; Rodgers, Kasey E.; Kenyon, Cynthia

2011-01-01

The analysis of morphological changes that occur in the nervous system during normal aging could provide insight into cognitive decline and neurodegenerative disease. Previous studies have suggested that the nervous system of C. elegans maintains its structural integrity with age despite the deterioration of surrounding tissues. Unexpectedly, we observed that neurons in aging animals frequently displayed ectopic branches, and that the prevalence of these branches increased with time. Within age-matched populations, the branching of mechnosensory neurons correlated with decreased response to light touch and decreased mobility. The incidence of branching was influenced by two pathways that can affect the rate of aging, the Jun kinase pathway and the insulin/IGF-1 pathway. Loss of Jun kinase signaling, which slightly shortens lifespan, dramatically increased and accelerated the frequency of neurite branching. Conversely, inhibition of the daf-2 insulin/IGF-1-like signaling pathway, which extends lifespan, delayed and suppressed branching, and this delay required DAF-16/FOXO activity. Both JNK-1 and DAF-16 appeared to act within neurons in a cell-autonomous manner to influence branching, and, through their tissue-specific expression, it was possible to disconnect the rate at which branching occurred from the overall rate of aging of the animal. Old age has generally been associated with the decline and deterioration of different tissues, except in the case of tumor cell growth. To our knowledge, this is the first indication that aging can potentiate another form of growth, the growth of neurite branches, in normal animals. PMID:21697377

Neurophysiological correlates of attention behavior in early infancy: Implications for emotion regulation during early childhood

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Perry, Nicole B.; Swingler, Margaret M.; Calkins, Susan D.; Bell, Martha Ann

2015-01-01

Current theoretical conceptualizations of regulatory development suggest that attention processes and emotion regulation processes share common neurophysiological underpinnings and behavioral antecedents such that emotion regulation abilities may build upon early attentional skills. To further elucidate this proposed relationship, we tested whether early neurophysiological processes measured during an attention task in infancy predicted in-task attention behavior, and whether infant's attention behavior was subsequently associated with their ability to regulate emotion in early childhood (N=388). Results indicated that, greater EEG power change (from baseline to task) at medial frontal locations (F3 and F4) during an attention task at 10 months were associated with concurrent observed behavioral attention. Specifically, greater change in EEG power at the right frontal location (F4) was associated with more attention, and greater EEG power at the left frontal location (F3) was associated with less attention, indicating a potential right hemisphere specialization for attention processes already present in the first year of life. In addition, after controlling for 5-month attention behavior, increased behavioral attention at 10-months was negatively associated with children's observed frustration to emotional challenge at age 3. Finally, the indirect effects from 10-month EEG power change at F3 and F4 to 3-year emotion regulation via infants' 10-month behavioral attention were significant, suggesting that infant's attention behavior is one mechanism through which early neurophysiological activity is related to emotion regulation abilities in childhood. PMID:26381926

Neurite orientation dispersion and density imaging in the substantia nigra in idiopathic Parkinson disease.

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Kamagata, Koji; Hatano, Taku; Okuzumi, Ayami; Motoi, Yumiko; Abe, Osamu; Shimoji, Keigo; Kamiya, Kouhei; Suzuki, Michimasa; Hori, Masaaki; Kumamaru, Kanako K; Hattori, Nobutaka; Aoki, Shigeki

2016-08-01

We used neurite orientation dispersion and density imaging (NODDI) to quantify changes in the substantia nigra pars compacta (SNpc) and striatum in Parkinson disease (PD). Diffusion-weighted magnetic resonance images were acquired from 58 PD patients and 36 age- and sex-matched controls. The intracellular volume fraction (Vic), orientation dispersion index (OD), and isotropic volume fraction (Viso) of the basal ganglia were compared between groups. Multivariate logistic regression analysis determined which diffusion parameters were independent predictors of PD. Receiver operating characteristic (ROC) analysis compared the diagnostic accuracies of the evaluated indices. Pearson coefficient analysis correlated each diffusional parameter with disease severity. Vic in the contralateral SNpc and putamen were significantly lower in PD patients than in healthy controls (P disease severity. Multivariate logistic analysis revealed that Vic (P = 0.0000046) and mean diffusivity (P = 0.019) in the contralateral SNpc were the independent predictors of PD. In the ROC analysis, Vic in the contralateral SNpc showed the best diagnostic performance (mean cutoff, 0.62; sensitivity, 0.88; specificity, 0.83). NODDI is likely to be useful for diagnosing PD and assessing its progression. • Neurite orientation dispersion and density imaging (NODDI) is a new diffusion MRI technique • NODDI estimates neurite microstructure more specifically than diffusion tensor imaging • By using NODDI, nigrostriatal alterations in PD can be evaluated in vivo • NOODI is useful for diagnosing PD and assessing its disease progression.

Electrical stimulation of schwann cells promotes sustained increases in neurite outgrowth.

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Koppes, Abigail N; Nordberg, Andrea L; Paolillo, Gina M; Goodsell, Nicole M; Darwish, Haley A; Zhang, Linxia; Thompson, Deanna M

2014-02-01

Endogenous electric fields are instructive during embryogenesis by acting to direct cell migration, and postnatally, they can promote axonal growth after injury (McCaig 1991, Al-Majed 2000). However, the mechanisms for these changes are not well understood. Application of an appropriate electrical stimulus may increase the rate and success of nerve repair by directly promoting axonal growth. Previously, DC electrical stimulation at 50 mV/mm (1 mA, 8 h duration) was shown to promote neurite outgrowth and a more pronounced effect was observed if both peripheral glia (Schwann cells) and neurons were co-stimulated. If electrical stimulation is delivered to an injury site, both the neurons and all resident non-neuronal cells [e.g., Schwann cells, endothelial cells, fibroblasts] will be treated and this biophysical stimuli can influence axonal growth directly or indirectly via changes to the resident, non-neuronal cells. In this work, non-neuronal cells were electrically stimulated, and changes in morphology and neuro-supportive cells were evaluated. Schwann cell response (morphology and orientation) was examined after an 8 h stimulation over a range of DC fields (0-200 mV/mm, DC 1 mA), and changes in orientation were observed. Electrically prestimulating Schwann cells (50 mV/mm) promoted 30% more neurite outgrowth relative to co-stimulating both Schwann cells with neurons, suggesting that electrical stimulation modifies Schwann cell phenotype. Conditioned medium from the electrically prestimulated Schwann cells promoted a 20% increase in total neurite outgrowth and was sustained for 72 h poststimulation. An 11-fold increase in nerve growth factor but not brain-derived neurotrophic factor or glial-derived growth factor was found in the electrically prestimulated Schwann cell-conditioned medium. No significant changes in fibroblast or endothelial morphology and neuro-supportive behavior were observed poststimulation. Electrical stimulation is widely used in

ZDHHC3 Tyrosine Phosphorylation Regulates Neural Cell Adhesion Molecule Palmitoylation

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Lievens, Patricia Marie-Jeanne; Kuznetsova, Tatiana; Kochlamazashvili, Gaga; Cesca, Fabrizia; Gorinski, Natalya; Galil, Dalia Abdel; Cherkas, Volodimir; Ronkina, Natalia; Lafera, Juri; Gaestel, Matthias

2016-01-01

The neural cell adhesion molecule (NCAM) mediates cell-cell and cell-matrix adhesion. It is broadly expressed in the nervous system and regulates neurite outgrowth, synaptogenesis, and synaptic plasticity. Previous in vitro studies revealed that palmitoylation of NCAM is required for fibroblast growth factor 2 (FGF2)-stimulated neurite outgrowth and identified the zinc finger DHHC (Asp-His-His-Cys)-containing proteins ZDHHC3 and ZDHHC7 as specific NCAM-palmitoylating enzymes. Here, we verified that FGF2 controlled NCAM palmitoylation in vivo and investigated molecular mechanisms regulating NCAM palmitoylation by ZDHHC3. Experiments with overexpression and pharmacological inhibition of FGF receptor (FGFR) and Src revealed that these kinases control tyrosine phosphorylation of ZDHHC3 and that ZDHHC3 is phosphorylated by endogenously expressed FGFR and Src proteins. By site-directed mutagenesis, we found that Tyr18 is an FGFR1-specific ZDHHC3 phosphorylation site, while Tyr295 and Tyr297 are specifically phosphorylated by Src kinase in cell-based and cell-free assays. Abrogation of tyrosine phosphorylation increased ZDHHC3 autopalmitoylation, enhanced interaction with NCAM, and upregulated NCAM palmitoylation. Expression of ZDHHC3 with tyrosine mutated in cultured hippocampal neurons promoted neurite outgrowth. Our findings for the first time highlight that FGFR- and Src-mediated tyrosine phosphorylation of ZDHHC3 modulates ZDHHC3 enzymatic activity and plays a role in neuronal morphogenesis. PMID:27247265

Regulation of bone morphogenetic proteins in early embryonic development

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Yamamoto, Yukiyo; Oelgeschläger, Michael

2004-11-01

Bone morphogenetic proteins (BMPs), a large subgroup of the TGF-β family of secreted growth factors, control fundamental events in early embryonic development, organogenesis and adult tissue homeostasis. The plethora of dose-dependent cellular processes regulated by BMP signalling demand a tight regulation of BMP activity. Over the last decade, a number of proteins have been identified that bind BMPs in the extracellular space and regulate the interaction of BMPs with their cognate receptors, including the secreted BMP antagonist Chordin. In the early vertebrate embryo, the localized secretion of BMP antagonists from the dorsal blastopore lip establishes a functional BMP signalling gradient that is required for the determination of the dorsoventral or back to belly body axis. In particular, inhibition of BMP activity is essential for the formation of neural tissue in the development of vertebrate and invertebrate embryos. Here we review recent studies that have provided new insight into the regulation of BMP signalling in the extracellular space. In particular, we discuss the recently identified Twisted gastrulation protein that modulates, in concert with metalloproteinases of the Tolloid family, the interaction of Chordin with BMP and a family of proteins that share structural similarities with Chordin in the respective BMP binding domains. In addition, genetic and functional studies in zebrafish and frog provide compelling evidence that the secreted protein Sizzled functionally interacts with the Chd BMP pathway, despite being expressed ventrally in the early gastrula-stage embryo. These intriguing discoveries may have important implications, not only for our current concept of early embryonic patterning, but also for the regulation of BMP activity at later developmental stages and tissue homeostasis in the adult.

A three-dimensional image processing program for accurate, rapid, and semi-automated segmentation of neuronal somata with dense neurite outgrowth

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Ross, James D.; Cullen, D. Kacy; Harris, James P.; LaPlaca, Michelle C.; DeWeerth, Stephen P.

2015-01-01

Three-dimensional (3-D) image analysis techniques provide a powerful means to rapidly and accurately assess complex morphological and functional interactions between neural cells. Current software-based identification methods of neural cells generally fall into two applications: (1) segmentation of cell nuclei in high-density constructs or (2) tracing of cell neurites in single cell investigations. We have developed novel methodologies to permit the systematic identification of populations of neuronal somata possessing rich morphological detail and dense neurite arborization throughout thick tissue or 3-D in vitro constructs. The image analysis incorporates several novel automated features for the discrimination of neurites and somata by initially classifying features in 2-D and merging these classifications into 3-D objects; the 3-D reconstructions automatically identify and adjust for over and under segmentation errors. Additionally, the platform provides for software-assisted error corrections to further minimize error. These features attain very accurate cell boundary identifications to handle a wide range of morphological complexities. We validated these tools using confocal z-stacks from thick 3-D neural constructs where neuronal somata had varying degrees of neurite arborization and complexity, achieving an accuracy of ≥95%. We demonstrated the robustness of these algorithms in a more complex arena through the automated segmentation of neural cells in ex vivo brain slices. These novel methods surpass previous techniques by improving the robustness and accuracy by: (1) the ability to process neurites and somata, (2) bidirectional segmentation correction, and (3) validation via software-assisted user input. This 3-D image analysis platform provides valuable tools for the unbiased analysis of neural tissue or tissue surrogates within a 3-D context, appropriate for the study of multi-dimensional cell-cell and cell-extracellular matrix interactions. PMID

Effect of Testosterone on Neuronal Morphology and Neuritic Growth of Fetal Lamb Hypothalamus-Preoptic Area and Cerebral Cortex in Primary Culture.

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Radhika C Reddy

Full Text Available Testosterone plays an essential role in sexual differentiation of the male sheep brain. The ovine sexually dimorphic nucleus (oSDN, is 2 to 3 times larger in males than in females, and this sex difference is under the control of testosterone. The effect of testosterone on oSDN volume may result from enhanced expansion of soma areas and/or dendritic fields. To test this hypothesis, cells derived from the hypothalamus-preoptic area (HPOA and cerebral cortex (CTX of lamb fetuses were grown in primary culture to examine the direct morphological effects of testosterone on these cellular components. We found that within two days of plating, neurons derived from both the HPOA and CTX extend neuritic processes and express androgen receptors and aromatase immunoreactivity. Both treated and control neurites continue to grow and branch with increasing time in culture. Treatment with testosterone (10 nM for 3 days significantly (P < 0.05 increased both total neurite outgrowth (35% and soma size (8% in the HPOA and outgrowth (21% and number of branch points (33% in the CTX. These findings indicate that testosterone-induced somal enlargement and neurite outgrowth in fetal lamb neurons may contribute to the development of a fully masculine sheep brain.

Neurite outgrowth stimulatory effects of myco­synthesized AuNPs from Hericium erinaceus (Bull.: Fr. Pers. on pheochromocytoma (PC-12 cells

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Raman J

2015-09-01

Full Text Available Jegadeesh Raman,1 Hariprasath Lakshmanan,1 Priscilla A John,1,2 Chan Zhijian,3 Vengadesh Periasamy,3 Pamela David,1,4 Murali Naidu,1,4 Vikineswary Sabaratnam1,2 1Mushroom Research Centre, 2Institute of Biological Sciences, Faculty of Science, University of Malaya, 3Low Dimensional Materials Research Center (LDMRC, Department of Physics, Faculty of Science, 4Department of Anatomy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia Background: Hericium erinaceus has been reported to have a wide range of medicinal properties such as stimulation of neurite outgrowth, promotion of functional recovery of axonotmetic peroneal nerve injury, antioxidant, antihypertensive, and antidiabetic properties. In recent years, the green synthesis of gold nanoparticles (AuNPs has attracted intense interest due to the potential use in biomedical applications. The aim of this study was to investigate the effects of AuNPs from aqueous extract of H. erinaceus on neurite outgrowth of rat pheochromocytoma (PC-12 cells. Methods: The formation of AuNPs was characterized by UV–visible spectrum, energy dispersive X-ray (EDX, field-emission scanning electron microscope (FESEM, transmission electron microscopy (TEM, particle size distribution, and Fourier transform-infrared spectroscopy (FTIR. Furthermore, the neurite extension study of synthesized AuNPs was evaluated by in vitro assay. Results: The AuNPs exhibited maximum absorbance between 510 and 600 nm in UV–visible spectrum. FESEM and TEM images showed the existence of nanoparticles with sizes of 20–40 nm. FTIR measurements were carried out to identify the possible biomolecules responsible for capping and efficient stabilization of the nanoparticles. The purity and the crystalline properties were confirmed by EDX diffraction analysis, which showed strong signals with energy peaks in the range of 2–2.4 keV, indicating the existence of gold atoms. The synthesized AuNPs showed significant neurite

Physiological correlates of emotional reactivity and regulation in early adolescents.

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Latham, Melissa D; Cook, Nina; Simmons, Julian G; Byrne, Michelle L; Kettle, Jonathan W L; Schwartz, Orli; Vijayakumar, Nandita; Whittle, Sarah; Allen, Nicholas B

2017-07-01

Few studies have examined physiological correlates of emotional reactivity and regulation in adolescents, despite the occurrence in this group of significant developmental changes in emotional functioning. The current study employed multiple physiological measures (i.e., startle-elicited eyeblink and ERP, skin conductance, facial EMG) to assess the emotional reactivity and regulation of 113 early adolescents in response to valenced images. Reactivity was measured while participants viewed images, and regulation was measured when they were asked to discontinue or maintain their emotional reactions to the images. Adolescent participants did not exhibit fear-potentiated startle blink. However, they did display affect-consistent zygomatic and corrugator activity during reactivity, as well as inhibition of some of these facial patterns during regulation. Skin conductance demonstrated arousal dependent activity during reactivity, and overall decreases during regulation. These findings suggest that early adolescents display reactivity to valenced pictures, but not to startle probes. Psychophysiological patterns during emotion regulation indicate additional effort and/or attention during the regulation process. Copyright © 2017 Elsevier B.V. All rights reserved.

Ca2+ toxicity due to reverse Na+/Ca2+ exchange contributes to degeneration of neurites of DRG neurons induced by a neuropathy-associated Nav1.7 mutation

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Estacion, M.; Vohra, B. P. S; Liu, S.; Hoeijmakers, J.; Faber, C. G.; Merkies, I. S. J.; Lauria, G.; Black, J. A.

2015-01-01

Gain-of-function missense mutations in voltage-gated sodium channel Nav1.7 have been linked to small-fiber neuropathy, which is characterized by burning pain, dysautonomia and a loss of intraepidermal nerve fibers. However, the mechanistic cascades linking Nav1.7 mutations to axonal degeneration are incompletely understood. The G856D mutation in Nav1.7 produces robust changes in channel biophysical properties, including hyperpolarized activation, depolarized inactivation, and enhanced ramp and persistent currents, which contribute to the hyperexcitability exhibited by neurons containing Nav1.8. We report here that cell bodies and neurites of dorsal root ganglion (DRG) neurons transfected with G856D display increased levels of intracellular Na+ concentration ([Na+]) and intracellular [Ca2+] following stimulation with high [K+] compared with wild-type (WT) Nav1.7-expressing neurons. Blockade of reverse mode of the sodium/calcium exchanger (NCX) or of sodium channels attenuates [Ca2+] transients evoked by high [K+] in G856D-expressing DRG cell bodies and neurites. We also show that treatment of WT or G856D-expressing neurites with high [K+] or 2-deoxyglucose (2-DG) does not elicit degeneration of these neurites, but that high [K+] and 2-DG in combination evokes degeneration of G856D neurites but not WT neurites. Our results also demonstrate that 0 Ca2+ or blockade of reverse mode of NCX protects G856D-expressing neurites from degeneration when exposed to high [K+] and 2-DG. These results point to [Na+] overload in DRG neurons expressing mutant G856D Nav1.7, which triggers reverse mode of NCX and contributes to Ca2+ toxicity, and suggest subtype-specific blockade of Nav1.7 or inhibition of reverse NCX as strategies that might slow or prevent axon degeneration in small-fiber neuropathy. PMID:26156380

Early Family Relationships Predict Children’s Emotion Regulation and Defense Mechanisms

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Jallu Lindblom

2016-12-01

Full Text Available Early family relationships have been suggested to influence the development of children’s affect regulation, involving both emotion regulation and defense mechanisms. However, we lack research on the specific family predictors for these two forms of affect regulation, which have been conceptualized to differ in their functions and accessibility to consciousness. Accordingly, we examine how the (a quality and (b timing of family relationships during infancy predict child’s later emotion regulation and defense mechanisms. Parents (N = 703 reported autonomy and intimacy in marital and parenting relationships at the child’s ages of 2 and 12 months, and the child’s use of emotion regulation and immature and neurotic defenses at 7 to 8 years. As hypothesized, the results showed that functional early family relationships predicted children’s efficient emotion regulation, whereas dysfunctional relationships predicted reliance on defense mechanisms in middle childhood. Further, results showed a timing effect for neurotic defenses, partially confirming our hypothesis of early infancy being an especially important period for the development of defense mechanisms. The findings are discussed from the viewpoints of attachment and family dynamics, emotional self-awareness, and sense of security.

Neurite outgrowth induced by a synthetic peptide ligand of neural cell adhesion molecule requires fibroblast growth factor receptor activation

DEFF Research Database (Denmark)

Rønn, L C; Doherty, P; Holm, A

2000-01-01

identified a neuritogenic ligand, termed the C3 peptide, of the first immunoglobulin (lg) module of NCAM using a combinatorial library of synthetic peptides. Here we investigate whether stimulation of neurite outgrowth by this synthetic ligand of NCAM involves FGFRs. In primary cultures of cerebellar neurons...... from wild-type mice, the C3 peptide stimulated neurite outgrowth. This response was virtually absent in cultures of cerebellar neurons from transgenic mice expressing a dominant-negative form of the FGFR1. Likewise, in PC12E2 cells transiently expressing a dominant-negative form of the mouse FGFR1...

Mycolactone-mediated neurite degeneration and functional effects in cultured human and rat DRG neurons: Mechanisms underlying hypoalgesia in Buruli ulcer.

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Anand, U; Sinisi, M; Fox, M; MacQuillan, A; Quick, T; Korchev, Y; Bountra, C; McCarthy, T; Anand, P

2016-01-01

Mycolactone is a polyketide toxin secreted by the mycobacterium Mycobacterium ulcerans, responsible for the extensive hypoalgesic skin lesions characteristic of patients with Buruli ulcer. A recent pre-clinical study proposed that mycolactone may produce analgesia via activation of the angiotensin II type 2 receptor (AT2R). In contrast, AT2R antagonist EMA401 has shown analgesic efficacy in animal models and clinical trials for neuropathic pain. We therefore investigated the morphological and functional effects of mycolactone in cultured human and rat dorsal root ganglia (DRG) neurons and the role of AT2R using EMA401. Primary sensory neurons were prepared from avulsed cervical human DRG and rat DRG; 24 h after plating, neurons were incubated for 24 to 96 h with synthetic mycolactone A/B, followed by immunostaining with antibodies to PGP9.5, Gap43, β tubulin, or Mitotracker dye staining. Acute functional effects were examined by measuring capsaicin responses with calcium imaging in DRG neuronal cultures treated with mycolactone. Morphological effects: Mycolactone-treated cultures showed dramatically reduced numbers of surviving neurons and non-neuronal cells, reduced Gap43 and β tubulin expression, degenerating neurites and reduced cell body diameter, compared with controls. Dose-related reduction of neurite length was observed in mycolactone-treated cultures. Mitochondria were distributed throughout the length of neurites and soma of control neurons, but clustered in the neurites and soma of mycolactone-treated neurons. Functional effects: Mycolactone-treated human and rat DRG neurons showed dose-related inhibition of capsaicin responses, which were reversed by calcineurin inhibitor cyclosporine and phosphodiesterase inhibitor 3-isobutyl-1-Methylxanthine, indicating involvement of cAMP/ATP reduction. The morphological and functional effects of mycolactone were not altered by Angiotensin II or AT2R antagonist EMA401. Mycolactone induces toxic effects in DRG

ECR-MAPK regulation in liver early development.

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Zhao, Xiu-Ju; Zhuo, Hexian

2014-01-01

Early growth is connected to a key link between embryonic development and aging. In this paper, liver gene expression profiles were assayed at postnatal day 22 and week 16 of age. Meanwhile another independent animal experiment and cell culture were carried out for validation. Significance analysis of microarrays, qPCR verification, drug induction/inhibition assays, and metabonomics indicated that alpha-2u globulin (extracellular region)-socs2 (-SH2-containing signals/receptor tyrosine kinases)-ppp2r2a/pik3c3 (MAPK signaling)-hsd3b5/cav2 (metabolism/organization) plays a vital role in early development. Taken together, early development of male rats is ECR and MAPK-mediated coordination of cancer-like growth and negative regulations. Our data represent the first comprehensive description of early individual development, which could be a valuable basis for understanding the functioning of the gene interaction network of infant development.

Role of transglutaminase 2 in PAC1 receptor mediated protection against hypoxia-induced cell death and neurite outgrowth in differentiating N2a neuroblastoma cells.

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Algarni, Alanood S; Hargreaves, Alan J; Dickenson, John M

2017-03-15

The PAC 1 receptor and tissue transglutaminase (TG2) play important roles in neurite outgrowth and modulation of neuronal cell survival. In this study, we investigated the regulation of TG2 activity by the PAC 1 receptor in retinoic acid-induced differentiating N2a neuroblastoma cells. TG2 transamidase activity was determined using an amine incorporation and a peptide cross linking assay. In situ TG2 activity was assessed by visualising the incorporation of biotin-X-cadaverine using confocal microscopy. TG2 phosphorylation was monitored via immunoprecipitation and Western blotting. The role of TG2 in PAC 1 receptor-induced cytoprotection and neurite outgrowth was investigated by monitoring hypoxia-induced cell death and appearance of axonal-like processes, respectively. The amine incorporation and protein crosslinking activity of TG2 increased in a time and concentration-dependent manner following stimulation with pituitary adenylate cyclase-activating polypeptide-27 (PACAP-27). PACAP-27 mediated increases in TG2 activity were abolished by the TG2 inhibitors Z-DON and R283 and by pharmacological inhibition of protein kinase A (KT 5720 and Rp-cAMPs), protein kinase C (Ro 31-8220), MEK1/2 (PD 98059), and removal of extracellular Ca 2+ . Fluorescence microscopy demonstrated PACAP-27 induced in situ TG2 activity. TG2 inhibition blocked PACAP-27 induced attenuation of hypoxia-induced cell death and outgrowth of axon-like processes. TG2 activation and cytoprotection were also observed in human SH-SY5Y cells. Together, these results demonstrate that TG2 activity was stimulated downstream of the PAC 1 receptor via a multi protein kinase dependent pathway. Furthermore, PAC 1 receptor-induced cytoprotection and neurite outgrowth are dependent upon TG2. These results highlight the importance of TG2 in the cellular functions of the PAC 1 receptor. Copyright © 2017 Elsevier Inc. All rights reserved.

Identification of NCAM-binding peptides promoting neurite outgrowth via a heterotrimeric G-protein-coupled pathway

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Hansen, Raino Kristian; Christensen, Claus; Korshunova, Irina

2007-01-01

the fibroblast growth factor receptor, the Src-related non-receptor tyrosine kinase Fyn, and heterotrimeric G-proteins. Interestingly, neurite outgrowth stimulated by ENFIN2 and ENFIN11 was independent of signaling through fibroblast growth factor receptor and Fyn, but could be inhibited with pertussis toxin...

Dendritic branching of olfactory bulb mitral and tufted cells: regulation by TrkB.

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Fumiaki Imamura

2009-08-01

Full Text Available Projection neurons of mammalian olfactory bulb (OB, mitral and tufted cells, have dendrites whose morphologies are specifically differentiated for efficient odor information processing. The apical dendrite extends radially and arborizes in single glomerulus where it receives primary input from olfactory sensory neurons that express the same odor receptor. The lateral dendrites extend horizontally in the external plexiform layer and make reciprocal dendrodendritic synapses with granule cells, which moderate mitral/tufted cell activity. The molecular mechanisms regulating dendritic development of mitral/tufted cells is one of the unsolved important problems in the olfactory system. Here, we focused on TrkB receptors to test the hypothesis that neurotrophin-mediate mechanisms contributed to dendritic differentiation of OB mitral/tufted cells.With immunohistochemical analysis, we found that the TrkB neurotrophin receptor is expressed by both apical and lateral dendrites of mitral/tufted cells and that expression is evident during the early postnatal days when these dendrites exhibit their most robust growth and differentiation. To examine the effect of TrkB activation on mitral/tufted cell dendritic development, we cultured OB neurons. When BDNF or NT4 were introduced into the cultures, there was a significant increase in the number of primary neurites and branching points among the mitral/tufted cells. Moreover, BDNF facilitated filopodial extension along the neurites of mitral/tufted cells.In this report, we show for the first time that TrkB activation stimulates the dendritic branching of mitral/tufted cells in developing OB. This suggests that arborization of the apical dendrite in a glomerulus is under the tight regulation of TrkB activation.

Electrical Stimulation of Schwann Cells Promotes Sustained Increases in Neurite Outgrowth

OpenAIRE

Koppes, Abigail N.; Nordberg, Andrea L.; Paolillo, Gina M.; Goodsell, Nicole M.; Darwish, Haley A.; Zhang, Linxia; Thompson, Deanna M.

2013-01-01

Endogenous electric fields are instructive during embryogenesis by acting to direct cell migration, and postnatally, they can promote axonal growth after injury (McCaig 1991, Al-Majed 2000). However, the mechanisms for these changes are not well understood. Application of an appropriate electrical stimulus may increase the rate and success of nerve repair by directly promoting axonal growth. Previously, DC electrical stimulation at 50 mV/mm (1 mA, 8 h duration) was shown to promote neurite ou...

Inhibitory Activity of Yokukansankachimpihange against Nerve Growth Factor-Induced Neurite Growth in Cultured Rat Dorsal Root Ganglion Neurons

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Chiaki Murayama

2015-08-01

Full Text Available Chronic pruritus is a major and distressing symptom of many cutaneous diseases, however, the treatment remains a challenge in the clinic. The traditional Chinese-Japanese medicine (Kampo medicine is a conservative and increasingly popular approach to treat chronic pruritus for both patients and medical providers. Yokukansankachimpihange (YKH, a Kampo formula has been demonstrated to be effective in the treatment of itching of atopic dermatitis in Japan although its pharmacological mechanism is unknown clearly. In an attempt to clarify its pharmacological actions, in this study, we focused on the inhibitory activity of YKH against neurite growth induced with nerve growth factor (NGF in cultured rat dorsal root ganglion (DRG neurons because epidermal hyperinnervation is deeply related to itch sensitization. YKH showed approximately 200-fold inhibitory activity against NGF-induced neurite growth than that of neurotropin (positive control, a drug used clinically for treatment of chronic pruritus. Moreover, it also found that Uncaria hook, Bupleurum root and their chemical constituents rhynchophylline, hirsutine, and saikosaponin a, d showed inhibitory activities against NGF-induced neurite growth, suggesting they should mainly contribute to the inhibitory activity of YKH. Further study on the effects of YKH against epidermal nerve density in “itch-scratch” animal models is under investigation.

ECR-MAPK Regulation in Liver Early Development

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Xiu-Ju Zhao

2014-01-01

Full Text Available Early growth is connected to a key link between embryonic development and aging. In this paper, liver gene expression profiles were assayed at postnatal day 22 and week 16 of age. Meanwhile another independent animal experiment and cell culture were carried out for validation. Significance analysis of microarrays, qPCR verification, drug induction/inhibition assays, and metabonomics indicated that alpha-2u globulin (extracellular region-socs2 (-SH2-containing signals/receptor tyrosine kinases-ppp2r2a/pik3c3 (MAPK signaling-hsd3b5/cav2 (metabolism/organization plays a vital role in early development. Taken together, early development of male rats is ECR and MAPK-mediated coordination of cancer-like growth and negative regulations. Our data represent the first comprehensive description of early individual development, which could be a valuable basis for understanding the functioning of the gene interaction network of infant development.

Effects of huperzine A on secretion of nerve growth factor in cultured rat cortical astrocytes and neurite outgrowth in rat PC12 cells.

Science.gov (United States)

Tang, Li-li; Wang, Rui; Tang, Xi-can

2005-06-01

To study the effects of huperzine A (HupA) on neuritogenic activity and the expression of nerve growth factor (NGF). After being treated with 10 micromol/L HupA, neurite outgrowth of PC12 cells was observed and counted under phase-contrast microscopy. Mitogenic activity was assayed by [3H]thymidine incorporation. Cell cytotoxicity was evaluated by lactate dehydrogenase (LDH) release. AChE activity, mRNA and protein expression were measured by the Ellman method, RT-PCR, and Western blot, respectively. NGF mRNA and protein levels were determined by RT-PCR and ELISA assays. Treatment of PC12 cells with 10 micromol/L HupA for 48 h markedly increased the number of neurite-bearing cells, but caused no significant alteration in cell viability or other signs of cytotoxicity. In addition to inhibiting AChE activity, 10 micromol/L HupA also increased the mRNA and protein levels of this enzyme. In addition, following 2 h exposure of the astrocytes to 10 micromol/L HupA, there was a significant up-regulation of mRNA for NGF and P75 low-affinity NGF receptor. The protein level of NGF was also increased after 24 h treatment with HupA. Our findings demonstrate for the first time that HupA has a direct or indirect neurotrophic activity, which might be beneficial in treatment of neurodegenerative disorders such as Alzheimer disease.

Neurite outgrowth stimulatory effects of culinary-medicinal mushrooms and their toxicity assessment using differentiating Neuro-2a and embryonic fibroblast BALB/3T3

OpenAIRE

Phan, Chia-Wei; David, Pamela; Naidu, Murali; Wong, Kah-Hui; Sabaratnam, Vikineswary

2013-01-01

Background Mushrooms are not only regarded as gourmet cuisine but also as therapeutic agent to promote cognition health. However, little toxicological information is available regarding their safety. Therefore, the aim of this study was to screen selected ethno-pharmacologically important mushrooms for stimulatory effects on neurite outgrowth and to test for any cytotoxicity. Methods The stimulatory effect of mushrooms on neurite outgrowth was assessed in differentiating mouse neuroblastoma (...

Neurite silenciosa na hanseníase multibacilar avaliada através da evolução das incapacidades antes, durante e após a poliquimioterapia

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Pimentel Maria Inês Fernandes

2004-01-01

Full Text Available FUNDAMENTOS: A neurite silenciosa é definida como deterioração da função nervosa na ausência de dor neural, diferenciando-se da neurite franca, em que ocorre dor no nervo periférico, com ou sem prejuízo da função nervosa. Sua detecção precoce é importante para tentar impedir o estabelecimento de seqüelas decorrentes da hanseníase. OBJETIVOS: Conhecer a freqüência das neurites silenciosas em portadores de formas multibacilares de hanseníase. MÉTODOS: Cento e três pacientes (18,4% BB, 47,6% BL e 34% LL foram acompanhados durante o período médio de 64,6 meses a partir do momento do diagnóstico, durante e após a poliquimioterapia, por meio da avaliação do grau de incapacidade. RESULTADOS: Foram analisados doentes que tiveram piora do grau de incapacidade no término de tratamento, ou ao fim do seguimento, em relação ao grau manifestado antes do tratamento ou no término do tratamento medicamentoso. Ao todo, pelo menos cinco pacientes (4,9% do total evoluíram com neurite silenciosa, durante ou após a poliquimioterapia. CONCLUSÃO: Preconiza-se exame neurológico seqüencial cuidadoso dos pacientes multibacilares, de modo a detectar e tratar precocemente a neurite silenciosa.

Neurite outgrowth in human induced pluripotent stem cell-derived neurons as a high-throughput screen for developmental neurotoxicity or neurotoxicity.

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Ryan, Kristen R; Sirenko, Oksana; Parham, Fred; Hsieh, Jui-Hua; Cromwell, Evan F; Tice, Raymond R; Behl, Mamta

2016-03-01

Due to the increasing prevalence of neurological disorders and the large number of untested compounds in the environment, there is a need to develop reliable and efficient screening tools to identify environmental chemicals that could potentially affect neurological development. Herein, we report on a library of 80 compounds screened for their ability to inhibit neurite outgrowth, a process by which compounds may elicit developmental neurotoxicity, in a high-throughput, high-content assay using human neurons derived from induced pluripotent stem cells (iPSC). The library contains a diverse set of compounds including those that have been known to be associated with developmental neurotoxicity (DNT) and/or neurotoxicity (NT), environmental compounds with unknown neurotoxic potential (e.g., polycyclic aromatic hydrocarbons (PAHs) and flame retardants (FRs)), as well as compounds with no documented neurotoxic potential. Neurons were treated for 72h across a 6-point concentration range (∼0.3-100μM) in 384-well plates. Effects on neurite outgrowth were assessed by quantifying total outgrowth, branches, and processes. We also assessed the number ofviable cells per well. Concentration-response profiles were evaluated using a Hill model to derive benchmark concentration (BMC) values. Assay performance was evaluated using positive and negative controls and test replicates. Compounds were ranked by activity and selectivity (i.e., specific effects on neurite outgrowth in the absence of concomitant cytotoxicity) and repeat studies were conducted to confirm selectivity. Among the 80 compounds tested, 38 compounds were active, of which 16 selectively inhibited neurite outgrowth. Of these 16 compounds, 12 were known to cause DNT/NT and the remaining 4 compounds included 3 PAHs and 1 FR. In independent repeat studies, 14/16 selective compounds were reproducibly active in the assay, of which only 6 were selective for inhibition of neurite outgrowth. These 6 compounds were

Transcallosal Projections Require Glycoprotein M6-Dependent Neurite Growth and Guidance.

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Mita, Sakura; de Monasterio-Schrader, Patricia; Fünfschilling, Ursula; Kawasaki, Takahiko; Mizuno, Hidenobu; Iwasato, Takuji; Nave, Klaus-Armin; Werner, Hauke B; Hirata, Tatsumi

2015-11-01

The function of mature neurons critically relies on the developmental outgrowth and projection of their cellular processes. It has long been postulated that the neuronal glycoproteins M6a and M6b are involved in axon growth because these four-transmembrane domain-proteins of the proteolipid protein family are highly enriched on growth cones, but in vivo evidence has been lacking. Here, we report that the function of M6 proteins is required for normal axonal extension and guidance in vivo. In mice lacking both M6a and M6b, a severe hypoplasia of axon tracts was manifested. Most strikingly, the corpus callosum was reduced in thickness despite normal densities of cortical projection neurons. In single neuron tracing, many axons appeared shorter and disorganized in the double-mutant cortex, and some of them were even misdirected laterally toward the subcortex. Probst bundles were not observed. Upon culturing, double-mutant cortical and cerebellar neurons displayed impaired neurite outgrowth, indicating a cell-intrinsic function of M6 proteins. A rescue experiment showed that the intracellular loop of M6a is essential for the support of neurite extension. We propose that M6 proteins are required for proper extension and guidance of callosal axons that follow one of the most complex trajectories in the mammalian nervous system. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Contemplative Practices in Early Childhood: Implications for Self-Regulation Skills and School Readiness

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Willis, Elizabeth; Dinehart, Laura H.

2014-01-01

This article examines the development of self-regulation skills in early childhood and the possibilities of children's contemplative practices as a viable tool to facilitate this development. Current research indicates that self-regulation skills in early childhood education make a significant contribution to school readiness, and long-term…

Early experience with 'new federalism' in health insurance regulation.

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Pollitz, K; Tapay, N; Hadley, E; Specht, J

2000-01-01

The authors monitored the implementation of the Health Insurance Portability and Accountability Act (HIPAA) from 1997 to 1999. Regulators in all states and relevant federal agencies were interviewed and applicable laws and regulations studied. The authors found that HIPAA changed legal protections for consumers' health coverage in several ways. They examine how the process of regulating such coverage was affected at the state and federal levels and under an emerging partnership of the two. Despite some early implementation challenges, HIPAA's successes have been significant, although limited by the law's incremental nature.

Neurite outgrowth is significantly increased by the simultaneous presentation of Schwann cells and moderate exogenous electric fields

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Koppes, Abigail N.; Seggio, Angela M.; Thompson, Deanna M.

2011-08-01

Axonal extension is influenced by a variety of external guidance cues; therefore, the development and optimization of a multi-faceted approach is probably necessary to address the intricacy of functional regeneration following nerve injury. In this study, primary dissociated neonatal rat dorsal root ganglia neurons and Schwann cells were examined in response to an 8 h dc electrical stimulation (0-100 mV mm-1). Stimulated samples were then fixed immediately, immunostained, imaged and analyzed to determine Schwann cell orientation and characterize neurite outgrowth relative to electric field strength and direction. Results indicate that Schwann cells are viable following electrical stimulation with 10-100 mV mm-1, and retain a normal morphology relative to unstimulated cells; however, no directional bias is observed. Neurite outgrowth was significantly enhanced by twofold following exposure to either a 50 mV mm-1 electric field (EF) or co-culture with unstimulated Schwann cells by comparison to neurons cultured alone. Neurite outgrowth was further increased in the presence of simultaneously applied cues (Schwann cells + 50 mV mm-1 dc EF), exhibiting a 3.2-fold increase over unstimulated control neurons, and a 1.2-fold increase over either neurons cultured with unstimulated Schwann cells or the electrical stimulus alone. These results indicate that dc electric stimulation in combination with Schwann cells may provide synergistic guidance cues for improved axonal growth relevant to nerve injuries in the peripheral nervous system.

Enhanced differentiation of neural stem cells to neurons and promotion of neurite outgrowth by oxygen-glucose deprivation.

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Wang, Qin; Yang, Lin; Wang, Yaping

2015-06-01

Stroke has become the leading cause of mortality worldwide. Hypoxic or ischemic insults are crucial factors mediating the neural damage in the brain tissue of stroke patients. Neural stem cells (NSCs) have been recognized as a promising tool for the treatment of ischemic stroke and other neurodegenerative diseases due to their inducible pluripotency. In this study, we aim to mimick the cerebral hypoxic-ischemic injury in vitro using oxygen-glucose deprivation (OGD) strategy, and evaluate the effects of OGD on the NSC's neural differentiation, as well as the differentiated neurite outgrowth. Our data showed that NSCs under the short-term 2h OGD treatment are able to maintain cell viability and the capability to form neurospheres. Importantly, this moderate OGD treatment promotes NSC differentiation to neurons and enhances the performance of the mature neuronal networks, accompanying increased neurite outgrowth of differentiated neurons. However, long-term 6h and 8h OGD exposures in NSCs lead to decreased cell survival, reduced differentiation and diminished NSC-derived neurite outgrowth. The expressions of neuron-specific microtubule-associated protein 2 (MAP-2) and growth associated protein 43 (GAP-43) are increased by short-term OGD treatments but suppressed by long-term OGD. Overall, our results demonstrate that short-term OGD exposure in vitro induces differentiation of NSCs while maintaining their proliferation and survival, providing valuable insights of adopting NSC-based therapy for ischemic stroke and other neurodegenerative disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of 710 nm visible light irradiation on neurite outgrowth in primary rat cortical neurons following ischemic insult

International Nuclear Information System (INIS)

Choi, Dong-Hee; Lee, Kyoung-Hee; Kim, Ji-Hye; Kim, Moon Young; Lim, Jeong Hoon; Lee, Jongmin

2012-01-01

Highlights: ► 710 nm wavelength light (LED) has a protective effect in the stroke animal model. ► We determined the effects of LED irradiation in vitro stroke model. ► LED treatment promotes the neurite outgrowth through MAPK activation. ► The level of synaptic markers significantly increased with LED treatment. ► LED treatment protects cell death in the in vitro stroke model. -- Abstract: Objective: We previously reported that 710 nm Light-emitting Diode (LED) has a protective effect through cellular immunity activation in the stroke animal model. However, whether LED directly protects neurons suffering from neurodegeneration was entirely unknown. Therefore, we sought to determine the effects of 710 nm visible light irradiation on neuronal protection and neuronal outgrowth in an in vitro stroke model. Materials and methods: Primary cultured rat cortical neurons were exposed to oxygen-glucose deprivation (OGD) and reoxygenation and normal conditions. An LED array with a peak wavelength of 710 nm was placed beneath the covered culture dishes with the room light turned off and were irradiated accordingly. LED treatments (4 min at 4 J/cm 2 and 50 mW/cm 2 ) were given once to four times within 8 h at 2 h intervals for 7 days. Mean neurite density, mean neurite diameter, and total fiber length were also measured after microtubule associated protein 2 (MAP2) immunostaining using the Axio Vision program. Synaptic marker expression and MAPK activation were confirmed by Western blotting. Results: Images captured after MAP2 immunocytochemistry showed significant (p < 0.05) enhancement of post-ischemic neurite outgrowth with LED treatment once and twice a day. MAPK activation was enhanced by LED treatment in both OGD-exposed and normal cells. The levels of synaptic markers such as PSD 95, GAP 43, and synaptophysin significantly increased with LED treatment in both OGD-exposed and normal cells (p < 0.05). Conclusion: Our data suggest that LED treatment may promote

Astrocytic αVβ3 integrin inhibits neurite outgrowth and promotes retraction of neuronal processes by clustering Thy-1.

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Rodrigo Herrera-Molina

Full Text Available Thy-1 is a membrane glycoprotein suggested to stabilize or inhibit growth of neuronal processes. However, its precise function has remained obscure, because its endogenous ligand is unknown. We previously showed that Thy-1 binds directly to α(Vβ(3 integrin in trans eliciting responses in astrocytes. Nonetheless, whether α(Vβ(3 integrin might also serve as a Thy-1-ligand triggering a neuronal response has not been explored. Thus, utilizing primary neurons and a neuron-derived cell line CAD, Thy-1-mediated effects of α(Vβ(3 integrin on growth and retraction of neuronal processes were tested. In astrocyte-neuron co-cultures, endogenous α(Vβ(3 integrin restricted neurite outgrowth. Likewise, α(Vβ(3-Fc was sufficient to suppress neurite extension in Thy-1(+, but not in Thy-1(- CAD cells. In differentiating primary neurons exposed to α(Vβ(3-Fc, fewer and shorter dendrites were detected. This effect was abolished by cleavage of Thy-1 from the neuronal surface using phosphoinositide-specific phospholipase C (PI-PLC. Moreover, α(Vβ(3-Fc also induced retraction of already extended Thy-1(+-axon-like neurites in differentiated CAD cells as well as of axonal terminals in differentiated primary neurons. Axonal retraction occurred when redistribution and clustering of Thy-1 molecules in the plasma membrane was induced by α(Vβ(3 integrin. Binding of α(Vβ(3-Fc was detected in Thy-1 clusters during axon retraction of primary neurons. Moreover, α(Vβ(3-Fc-induced Thy-1 clustering correlated in time and space with redistribution and inactivation of Src kinase. Thus, our data indicates that α(Vβ(3 integrin is a ligand for Thy-1 that upon binding not only restricts the growth of neurites, but also induces retraction of already existing processes by inducing Thy-1 clustering. We propose that these events participate in bi-directional astrocyte-neuron communication relevant to axonal repair after neuronal damage.

Enhanced Neural Cell Adhesion and Neurite Outgrowth on Graphene-Based Biomimetic Substrates

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Suck Won Hong

2014-01-01

Full Text Available Neural cell adhesion and neurite outgrowth were examined on graphene-based biomimetic substrates. The biocompatibility of carbon nanomaterials such as graphene and carbon nanotubes (CNTs, that is, single-walled and multiwalled CNTs, against pheochromocytoma-derived PC-12 neural cells was also evaluated by quantifying metabolic activity (with WST-8 assay, intracellular oxidative stress (with ROS assay, and membrane integrity (with LDH assay. Graphene films were grown by using chemical vapor deposition and were then coated onto glass coverslips by using the scooping method. Graphene sheets were patterned on SiO2/Si substrates by using photolithography and were then covered with serum for a neural cell culture. Both types of CNTs induced significant dose-dependent decreases in the viability of PC-12 cells, whereas graphene exerted adverse effects on the neural cells just at over 62.5 ppm. This result implies that graphene and CNTs, even though they were the same carbon-based nanomaterials, show differential influences on neural cells. Furthermore, graphene-coated or graphene-patterned substrates were shown to substantially enhance the adhesion and neurite outgrowth of PC-12 cells. These results suggest that graphene-based substrates as biomimetic cues have good biocompatibility as well as a unique surface property that can enhance the neural cells, which would open up enormous opportunities in neural regeneration and nanomedicine.

LMTK1 regulates dendritic formation by regulating movement of Rab11A-positive endosomes.

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Takano, Tetsuya; Urushibara, Tomoki; Yoshioka, Nozomu; Saito, Taro; Fukuda, Mitsunori; Tomomura, Mineko; Hisanaga, Shin-Ichi

2014-06-01

Neurons extend two types of neurites-axons and dendrites-that differ in structure and function. Although it is well understood that the cytoskeleton plays a pivotal role in neurite differentiation and extension, the mechanisms by which membrane components are supplied to growing axons or dendrites is largely unknown. We previously reported that the membrane supply to axons is regulated by lemur kinase 1 (LMTK1) through Rab11A-positive endosomes. Here we investigate the role of LMTK1 in dendrite formation. Down-regulation of LMTK1 increases dendrite growth and branching of cerebral cortical neurons in vitro and in vivo. LMTK1 knockout significantly enhances the prevalence, velocity, and run length of anterograde movement of Rab11A-positive endosomes to levels similar to those expressing constitutively active Rab11A-Q70L. Rab11A-positive endosome dynamics also increases in the cell body and growth cone of LMTK1-deficient neurons. Moreover, a nonphosphorylatable LMTK1 mutant (Ser34Ala, a Cdk5 phosphorylation site) dramatically promotes dendrite growth. Thus LMTK1 negatively controls dendritic formation by regulating Rab11A-positive endosomal trafficking in a Cdk5-dependent manner, indicating the Cdk5-LMTK1-Rab11A pathway as a regulatory mechanism of dendrite development as well as axon outgrowth. © 2014 Takano et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

The Role of ATP in the Regulation of NCAM Function

DEFF Research Database (Denmark)

Hübschmann, Martin; Skladchikova, Galina

2008-01-01

overlaps with the site of NCAM-FGFR interaction, and ATP is capable of disrupting NCAM-FGFR binding. This implies that NCAM signaling through FGFR can be regulated by ATP, which is supported by the observation that ATP can abrogate NCAM-induced neurite outgrowth. Finally, ATP can induce NCAM ectodomain...... shedding, possibly affecting the structural plasticity associated with learning and memory....

Lion's Mane, Hericium erinaceus and Tiger Milk, Lignosus rhinocerotis (Higher Basidiomycetes) Medicinal Mushrooms Stimulate Neurite Outgrowth in Dissociated Cells of Brain, Spinal Cord, and Retina: An In Vitro Study.

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Samberkar, Snehlata; Gandhi, Sivasangkary; Naidu, Murali; Wong, Kah-Hui; Raman, Jegadeesh; Sabaratnam, Vikineswary

2015-01-01

Neurodegenerative disease is defined as a deterioration of the nervous system in the intellectual and cognitive capabilities. Statistics show that more than 80-90 million individuals age 65 and above in 2050 may be affected by neurodegenerative conditions like Alzheimer's and Parkinson's disease. Studies have shown that out of 2000 different types of edible and/or medicinal mushrooms, only a few countable mushrooms have been selected until now for neurohealth activity. Hericium erinaceus is one of the well-established medicinal mushrooms for neuronal health. It has been documented for its regenerative capability in peripheral nerve. Another mushroom used as traditional medicine is Lignosus rhinocerotis, which has been used for various illnesses. It has been documented for its neurite outgrowth potential in PC12 cells. Based on the regenerative capabilities of both the mushrooms, priority was given to select them for our study. The aim of this study was to investigate the potential of H. erinaceus and L. rhinocerotis to stimulate neurite outgrowth in dissociated cells of brain, spinal cord, and retina from chick embryo when compared to brain derived neurotrophic factor (BDNF). Neurite outgrowth activity was confirmed by the immu-nofluorescence method in all tissue samples. Treatment with different concentrations of extracts resulted in neuronal differentiation and neuronal elongation. H. erinaceus extract at 50 µg/mL triggered neurite outgrowth at 20.47%, 22.47%, and 21.70% in brain, spinal cord, and retinal cells. L. rhinocerotis sclerotium extract at 50 µg/mL induced maximum neurite outgrowth of 20.77% and 24.73% in brain and spinal cord, whereas 20.77% of neurite outgrowth was observed in retinal cells at 25 µg/mL, respectively.

Effect of Exosomes from Rat Adipose-Derived Mesenchymal Stem Cells on Neurite Outgrowth and Sciatic Nerve Regeneration After Crush Injury.

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Bucan, Vesna; Vaslaitis, Desiree; Peck, Claas-Tido; Strauß, Sarah; Vogt, Peter M; Radtke, Christine

2018-06-21

Peripheral nerve injury requires optimal conditions in both macro-environment and microenvironment for promotion of axonal regeneration. However, most repair strategies of traumatic peripheral nerve injury often lead to dissatisfying results in clinical outcome. Though various strategies have been carried out to improve the macro-environment, the underlying molecular mechanism of axon regeneration in the microenvironment provided by nerve conduit remains unclear. In this study, we evaluate the effects of from adipose-derived mesenchymal stem cells (adMSCs) originating exosomes with respect to sciatic nerve regeneration and neurite growth. Molecular and immunohistochemical techniques were used to investigate the presence of characteristic exosome markers. A co-culture system was established to determine the effect of exosomes on neurite elongation in vitro. The in vivo walking behaviour of rats was evaluated by footprint analysis, and the nerve regeneration was assessed by immunocytochemistry. adMSCs secrete nano-vesicles known as exosomes, which increase neurite outgrowth in vitro and enhance regeneration after sciatic nerve injury in vivo. Furthermore, we showed the presence of neural growth factors transcripts in adMSC exosomes for the first time. Our results demonstrate that exosomes, constitutively produced by adMSCs, are involved in peripheral nerve regeneration and have the potential to be utilised as a therapeutic tool for effective tissue-engineered nerves.

Ubiquitination of MBNL1 Is Required for Its Cytoplasmic Localization and Function in Promoting Neurite Outgrowth

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Pei-Ying Wang

2018-02-01

Full Text Available The Muscleblind-like protein family (MBNL plays an important role in regulating the transition between differentiation and pluripotency and in the pathogenesis of myotonic dystrophy type 1 (DM1, a CTG expansion disorder. How different MBNL isoforms contribute to the differentiation and are affected in DM1 has not been investigated. Here, we show that the MBNL1 cytoplasmic, but not nuclear, isoform promotes neurite morphogenesis and reverses the morphological defects caused by expanded CUG RNA. Cytoplasmic MBNL1 is polyubiquitinated by lysine 63 (K63. Reduced cytoplasmic MBNL1 in the DM1 mouse brain is consistent with the reduced extent of K63 ubiquitination. Expanded CUG RNA induced the deubiqutination of cytoplasmic MBNL1, which resulted in nuclear translocation and morphological impairment that could be ameliorated by inhibiting K63-linked polyubiquitin chain degradation. Our results suggest that K63-linked ubiquitination of MBNL1 is required for its cytoplasmic localization and that deubiquitination of cytoplasmic MBNL1 is pathogenic in the DM1 brain.

Wnt5a regulates midbrain dopaminergic axon growth and guidance.

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Brette D Blakely

2011-03-01

Full Text Available During development, precise temporal and spatial gradients are responsible for guiding axons to their appropriate targets. Within the developing ventral midbrain (VM the cues that guide dopaminergic (DA axons to their forebrain targets remain to be fully elucidated. Wnts are morphogens that have been identified as axon guidance molecules. Several Wnts are expressed in the VM where they regulate the birth of DA neurons. Here, we describe that a precise temporo-spatial expression of Wnt5a accompanies the development of nigrostriatal projections by VM DA neurons. In mice at E11.5, Wnt5a is expressed in the VM where it was found to promote DA neurite and axonal growth in VM primary cultures. By E14.5, when DA axons are approaching their striatal target, Wnt5a causes DA neurite retraction in primary cultures. Co-culture of VM explants with Wnt5a-overexpressing cell aggregates revealed that Wnt5a is capable of repelling DA neurites. Antagonism experiments revealed that the effects of Wnt5a are mediated by the Frizzled receptors and by the small GTPase, Rac1 (a component of the non-canonical Wnt planar cell polarity pathway. Moreover, the effects were specific as they could be blocked by Wnt5a antibody, sFRPs and RYK-Fc. The importance of Wnt5a in DA axon morphogenesis was further verified in Wnt5a-/- mice, where fasciculation of the medial forebrain bundle (MFB as well as the density of DA neurites in the MFB and striatal terminals were disrupted. Thus, our results identify a novel role of Wnt5a in DA axon growth and guidance.

Three-dimensional fine structure of the organization of microtubules in neurite varicosities by ultra-high voltage electron microscope tomography.

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Nishida, Tomoki; Yoshimura, Ryoichi; Endo, Yasuhisa

2017-09-01

Neurite varicosities are highly specialized compartments that are involved in neurotransmitter/ neuromodulator release and provide a physiological platform for neural functions. However, it remains unclear how microtubule organization contributes to the form of varicosity. Here, we examine the three-dimensional structure of microtubules in varicosities of a differentiated PC12 neural cell line using ultra-high voltage electron microscope tomography. Three-dimensional imaging showed that a part of the varicosities contained an accumulation of organelles that were separated from parallel microtubule arrays. Further detailed analysis using serial sections and whole-mount tomography revealed microtubules running in a spindle shape of swelling in some other types of varicosities. These electron tomographic results showed that the structural diversity and heterogeneity of microtubule organization supported the form of varicosities, suggesting that a different distribution pattern of microtubules in varicosities is crucial to the regulation of varicosities development.

Cell death in neural precursor cells and neurons before neurite formation prevents the emergence of abnormal neural structures in the Drosophila optic lobe.

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Hara, Yusuke; Sudo, Tatsuya; Togane, Yu; Akagawa, Hiromi; Tsujimura, Hidenobu

2018-04-01

Programmed cell death is a conserved strategy for neural development both in vertebrates and invertebrates and is recognized at various developmental stages in the brain from neurogenesis to adulthood. To understand the development of the central nervous system, it is essential to reveal not only molecular mechanisms but also the role of neural cell death (Pinto-Teixeira et al., 2016). To understand the role of cell death in neural development, we investigated the effect of inhibition of cell death on optic lobe development. Our data demonstrate that, in the optic lobe of Drosophila, cell death occurs in neural precursor cells and neurons before neurite formation and functions to prevent various developmental abnormalities. When neuronal cell death was inhibited by an effector caspase inhibitor, p35, multiple abnormal neuropil structures arose during optic lobe development-e.g., enlarged or fused neuropils, misrouted neurons and abnormal neurite lumps. Inhibition of cell death also induced morphogenetic defects in the lamina and medulla development-e.g., failures in the separation of the lamina and medulla cortices and the medulla rotation. These defects were reproduced in the mutant of an initiator caspase, dronc. If cell death was a mechanism for removing the abnormal neuropil structures, we would also expect to observe them in mutants defective for corpse clearance. However, they were not observed in these mutants. When dead cell-membranes were visualized with Apoliner, they were observed only in cortices and not in neuropils. These results suggest that the cell death occurs before mature neurite formation. Moreover, we found that inhibition of cell death induced ectopic neuroepithelial cells, neuroblasts and ganglion mother cells in late pupal stages, at sites where the outer and inner proliferation centers were located at earlier developmental stages. Caspase-3 activation was observed in the neuroepithelial cells and neuroblasts in the proliferation centers

Physical Activity, Self-Regulation, and Early Academic Achievement in Preschool Children

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Becker, Derek R.; McClelland, Megan M.; Loprinzi, Paul; Trost, Stewart G.

2014-01-01

Research Findings: The present study investigated whether active play during recess was associated with self-regulation and academic achievement in a prekindergarten sample. A total of 51 children in classes containing approximately half Head Start children were assessed on self-regulation, active play, and early academic achievement. Path…

TRPC6 channel-mediated neurite outgrowth in PC12 cells and hippocampal neurons involves activation of RAS/MEK/ERK, PI3K, and CAMKIV signaling.

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Heiser, Jeanine H; Schuwald, Anita M; Sillani, Giacomo; Ye, Lian; Müller, Walter E; Leuner, Kristina

2013-11-01

The non-selective cationic transient receptor canonical 6 (TRPC6) channels are involved in synaptic plasticity changes ranging from dendritic growth, spine morphology changes and increase in excitatory synapses. We previously showed that the TRPC6 activator hyperforin, the active antidepressant component of St. John's wort, induces neuritic outgrowth and spine morphology changes in PC12 cells and hippocampal CA1 neurons. However, the signaling cascade that transmits the hyperforin-induced transient rise in intracellular calcium into neuritic outgrowth is not yet fully understood. Several signaling pathways are involved in calcium transient-mediated changes in synaptic plasticity, ranging from calmodulin-mediated Ras-induced signaling cascades comprising the mitogen-activated protein kinase, PI3K signal transduction pathways as well as Ca(2+) /calmodulin-dependent protein kinase II (CAMKII) and CAMKIV. We show that several mechanisms are involved in TRPC6-mediated synaptic plasticity changes in PC12 cells and primary hippocampal neurons. Influx of calcium via TRPC6 channels activates different pathways including Ras/mitogen-activated protein kinase/extracellular signal-regulated kinases, phosphatidylinositide 3-kinase/protein kinase B, and CAMKIV in both cell types, leading to cAMP-response element binding protein phosphorylation. These findings are interesting not only in terms of the downstream targets of TRPC6 channels but also because of their potential to facilitate further understanding of St. John's wort extract-mediated antidepressant activity. Alterations in synaptic plasticity are considered to play an important role in the pathogenesis of depression. Beside several other proteins, TRPC6 channels regulate synaptic plasticity. This study demonstrates that different pathways including Ras/MEK/ERK, PI3K/Akt, and CAMKIV are involved in the improvement of synaptic plasticity by the TRPC6 activator hyperforin, the antidepressant active constituent of St. John

A Role for EHD4 in the Regulation of Early Endosomal Transport

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Sharma, Mahak; Naslavsky, Naava; Caplan, Steve

2009-01-01

All four of the C-terminal Eps15 homology domain (EHD) proteins have been implicated in the regulation of endocytic trafficking. However, the high level of amino acid sequence identity among these proteins has made it challenging to elucidate the precise function of individual EHD proteins. We demonstrate here with specific peptide antibodies that endogenous EHD4 localizes to Rab5-, early embryonic antigen 1 (EEA1)- and Arf6-containing endosomes and colocalizes with internalized transferrin in the cell periphery. Knock-down of EHD4 expression by both small interfering RNA and short hairpin RNA leads to the generation of enlarged early endosomal structures that contain Rab5 and EEA1 as well as internalized transferrin or major histocompatibility complex class I molecules. In addition, cargo destined for degradation, such as internalized low-density lipoprotein, also accumulates in the enlarged early endosomes in EHD4-depleted cells. Moreover, we have demonstrated that these enlarged early endosomes are enriched in levels of the activated GTP-bound Rab5. Finally, we show that endogenous EHD4 and EHD1 interact in cells, suggesting coordinated involvement in the regulation of receptor transport along the early endosome to endocytic recycling compartment axis. The results presented herein provide evidence that EHD4 is involved in the control of trafficking at the early endosome and regulates exit of cargo toward both the recycling compartment and the late endocytic pathway. PMID:18331452

Quantitative assessment of neurite outgrowth in human embryonic stem-cell derived neurons using automated high-content image analysis

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During development neurons undergo a number of morphological changes including neurite outgrowth from the cell body. Exposure to neurotoxicants that interfere with this process may cause in permanent deficits in nervous system function. While many studies have used rodent primary...

Co-effects of matrix low elasticity and aligned topography on stem cell neurogenic differentiation and rapid neurite outgrowth

Science.gov (United States)

Yao, Shenglian; Liu, Xi; Yu, Shukui; Wang, Xiumei; Zhang, Shuming; Wu, Qiong; Sun, Xiaodan; Mao, Haiquan

2016-05-01

The development of novel biomaterials that deliver precise regulatory signals to direct stem cell fate for nerve regeneration is the focus of current intensive research efforts. In this study, a hierarchically aligned fibrillar fibrin hydrogel (AFG) that was fabricated through electrospinning and the concurrent molecular self-assembly process mimics both the soft and oriented features of nerve tissue, thus providing hybrid biophysical cues to instruct cell behavior in vitro and in vivo. The electrospun hydrogels were examined by scanning electron microscopy (SEM), polarized light microscopy, small angle X-ray scattering assay and atomic force microscopy (AFM), showing a hierarchically linear-ordered structure from the nanoscale to the macroscale with a soft elastic character (elasticity ~1 kPa). We found that this low elasticity and aligned topography of AFG exhibit co-effects on promoting the neurogenic differentiation of human umbilical cord mesenchymal stem cells (hUMSCs) in comparison to random fibrin hydrogel (RFG) and tissue culture plate (TCP) control after two week cell culture in growth medium lacking supplementation with soluble neurogenic induction factors. In addition, AFG also induces dorsal root ganglion (DRG) neurons to rapidly project numerous long neurite outgrowths longitudinally along the AFG fibers for a total neurite extension distance of 1.96 mm in three days in the absence of neurotrophic factor supplementation. Moreover, the AFG implanted in a rat T9 dorsal hemisection spinal cord injury model was found to promote endogenous neural cell fast migration and axonal invasion along AFG fibers, resulting in aligned tissue cables in vivo. Our results suggest that matrix stiffness and aligned topography may instruct stem cell neurogenic differentiation and rapid neurite outgrowth, providing great promise for biomaterial design for applications in nerve regeneration.The development of novel biomaterials that deliver precise regulatory signals to

Effect of 710 nm visible light irradiation on neurite outgrowth in primary rat cortical neurons following ischemic insult

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Choi, Dong-Hee [Center for Neuroscience Research, SMART Institute of Advanced Biomedical Science, Konkuk University, Seoul (Korea, Republic of); Department of Medical Science, Konkuk University School of Medicine, Seoul (Korea, Republic of); Lee, Kyoung-Hee; Kim, Ji-Hye; Kim, Moon Young [Center for Neuroscience Research, SMART Institute of Advanced Biomedical Science, Konkuk University, Seoul (Korea, Republic of); Lim, Jeong Hoon [Department of Rehabilitation Medicine, Konkuk University School of Medicine, Seoul (Korea, Republic of); Rehabilitation Medicine, Division of Neurology, Department of Medicine, National University Hospital, National University Health System (Singapore); Lee, Jongmin, E-mail: leej@kuh.ac.kr [Center for Neuroscience Research, SMART Institute of Advanced Biomedical Science, Konkuk University, Seoul (Korea, Republic of); Department of Rehabilitation Medicine, Konkuk University School of Medicine, Seoul (Korea, Republic of)

2012-06-01

Highlights: Black-Right-Pointing-Pointer 710 nm wavelength light (LED) has a protective effect in the stroke animal model. Black-Right-Pointing-Pointer We determined the effects of LED irradiation in vitro stroke model. Black-Right-Pointing-Pointer LED treatment promotes the neurite outgrowth through MAPK activation. Black-Right-Pointing-Pointer The level of synaptic markers significantly increased with LED treatment. Black-Right-Pointing-Pointer LED treatment protects cell death in the in vitro stroke model. -- Abstract: Objective: We previously reported that 710 nm Light-emitting Diode (LED) has a protective effect through cellular immunity activation in the stroke animal model. However, whether LED directly protects neurons suffering from neurodegeneration was entirely unknown. Therefore, we sought to determine the effects of 710 nm visible light irradiation on neuronal protection and neuronal outgrowth in an in vitro stroke model. Materials and methods: Primary cultured rat cortical neurons were exposed to oxygen-glucose deprivation (OGD) and reoxygenation and normal conditions. An LED array with a peak wavelength of 710 nm was placed beneath the covered culture dishes with the room light turned off and were irradiated accordingly. LED treatments (4 min at 4 J/cm{sup 2} and 50 mW/cm{sup 2}) were given once to four times within 8 h at 2 h intervals for 7 days. Mean neurite density, mean neurite diameter, and total fiber length were also measured after microtubule associated protein 2 (MAP2) immunostaining using the Axio Vision program. Synaptic marker expression and MAPK activation were confirmed by Western blotting. Results: Images captured after MAP2 immunocytochemistry showed significant (p < 0.05) enhancement of post-ischemic neurite outgrowth with LED treatment once and twice a day. MAPK activation was enhanced by LED treatment in both OGD-exposed and normal cells. The levels of synaptic markers such as PSD 95, GAP 43, and synaptophysin significantly

Salicin from Willow Bark can Modulate Neurite Outgrowth in Human Neuroblastoma SH-SY5Y Cells.

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Wölfle, Ute; Haarhaus, Birgit; Kersten, Astrid; Fiebich, Bernd; Hug, Martin J; Schempp, Christoph M

2015-10-01

Salicin from willow bark has been used throughout centuries in China and Europe for the treatment of pain, headache, and inflammatory conditions. Recently, it could be demonstrated that salicin binds and activates the bitter taste receptor TAS2R16. Studies on rodent tissues showed the general expression of bitter taste receptors (TAS2Rs) in rodent brain. Here, we demonstrate the expression of hTAS2R16 in human neuronal tissues and the neuroblastoma cell line SH-SY5Y. The functionality was analyzed in the neuroblastoma cell line SH-SY5Y after stimulation with salicin, a known TAS2R16 agonist. In this setting salicin induced in SH-SY5Y cells phosphorylation of ERK and CREB, the key transcription factor of neuronal differentiation. PD98059, an inhibitor of the ERK pathway, as well as probenecid, a TAS2R16 antagonist, inhibited receptor phosphorylation as well as neurite outgrowth. These data show that salicin might modulate neurite outgrowth by bitter taste receptor activation. Copyright © 2015 John Wiley & Sons, Ltd.

Effects of 4-aminopyridine on organelle movement in cultured mouse dorsal root ganglion neurites.

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Hiruma, Hiromi; Kawakami, Tadashi

2010-03-01

Aminopyridines, widely used as a K(+) channel blocker, are membrane-permeable weak bases and have the ability to form vacuoles in the cytoplasm. The vacuoles originate from acidic organelles such as lysosomes. Here, we investigated the effects of 4-aminopyridine (4-AP) on organelle movement in neurites of cultured mouse dorsal root ganglion (DRG) neurons by using video-enhanced microscopy. Some experiments were carried out using fluorescent dyes for lysosomes and mitochondria and confocal microscopy. Treatment of DRG neurons with 4 mM 4-AP caused Brownian movement of some lysosomes within 5 min. The Brownian movement gradually became rapid and vacuoles were formed around individual lysosomes 10-20 min after the start of treatment. Axonal transport of organelles was inhibited by 4-AP. Lysosomes showing Brownian movement were not transported in longitudinal direction of the neurite and the transport of mitochondria was interrupted by vacuoles. The 4-AP-induced Brownian movement of lysosomes with vacuole formation and inhibition of axonal transport were prevented by the simultaneous treatment with vacuolar H(+) ATPase inhibitor bafilomycin A1 or in Cl(-)-free SO(4)(2-) medium. These results indicate that changes in organelle movement by 4-AP are related to vacuole formation and the vacuolar H(+) ATPase and Cl(-) are required for the effects of 4-AP.

Early Behavioral Self-Regulation, Academic Achievement, and Gender: Longitudinal Findings from France, Germany, and Iceland

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Gestsdottir, Steinunn; von Suchodoletz, Antje; Wanless, Shannon B.; Hubert, Blandine; Guimard, Philippe; Birgisdottir, Freyja; Gunzenhauser, Catherine; McClelland, Megan

2014-01-01

Research suggests that behavioral self-regulation skills are critical for early school success, but few studies have explored such links among young children in Europe. This study examined the contribution of early self-regulation to academic achievement gains among children in France, Germany, and Iceland. Gender differences in behavioral…

Neurite outgrowth stimulatory effects of culinary-medicinal mushrooms and their toxicity assessment using differentiating Neuro-2a and embryonic fibroblast BALB/3T3

Science.gov (United States)

2013-01-01

Background Mushrooms are not only regarded as gourmet cuisine but also as therapeutic agent to promote cognition health. However, little toxicological information is available regarding their safety. Therefore, the aim of this study was to screen selected ethno-pharmacologically important mushrooms for stimulatory effects on neurite outgrowth and to test for any cytotoxicity. Methods The stimulatory effect of mushrooms on neurite outgrowth was assessed in differentiating mouse neuroblastoma (N2a) cells. Neurite length was measured using Image-Pro Insight processor system. Neuritogenesis activity was further validated by fluorescence immunocytochemical staining of neurofilaments. In vitro cytotoxicity was investigated by using mouse embryonic fibroblast (BALB/3T3) and N2a cells for any embryo- and neuro-toxic effects; respectively. Results Aqueous extracts of Ganoderma lucidum, Lignosus rhinocerotis, Pleurotus giganteus and Grifola frondosa; as well as an ethanol extract of Cordyceps militaris significantly (p < 0.05) promoted the neurite outgrowth in N2a cells by 38.4 ± 4.2%, 38.1 ± 2.6%, 33.4 ± 4.6%, 33.7 ± 1.5%, and 35.8 ± 3.4%; respectively. The IC50 values obtained from tetrazolium (MTT), neutral red uptake (NRU) and lactate dehydrogenase (LDH) release assays showed no toxic effects following 24 h exposure of N2a and 3T3 cells to mushroom extracts. Conclusion Our results indicate that G. lucidum, L. rhinocerotis, P. giganteus, G. frondosa and C. militaris may be developed as safe and healthy dietary supplements for brain and cognitive health. PMID:24119256

The Development of Prosocial Behaviour in Early Childhood: Contributions of Early Parenting and Self-Regulation

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Williams, Kate E.; Berthelsen, Donna

2017-01-01

This research considers the role of parenting practices and early self-regulation, on children's prosocial behaviour when they begin school. Data for 4007 children were drawn from "Growing Up in Australia: The Longitudinal Study of Australian Children" (LSAC). The analyses explored relations between self-reported parenting practices for…

Nanostructured Polyaniline Coating on ITO Glass Promotes the Neurite Outgrowth of PC 12 Cells by Electrical Stimulation.

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Wang, Liping; Huang, Qianwei; Wang, Jin-Ye

2015-11-10

A conducting polymer polyaniline (PANI) with nanostructure was synthesized on indium tin oxide (ITO) glass. The effect of electrical stimulation on the proliferation and the length of neurites of PC 12 cells was investigated. The dynamic protein adsorption on PANI and ITO surfaces in a cell culture medium was also compared with and without electrical stimulation. The adsorbed proteins were characterized using SDS-PAGE. A PANI coating on ITO surface was shown with 30-50 nm spherical nanostructure. The number of PC 12 cells was significantly greater on the PANI/ITO surface than on ITO and plate surfaces after cell seeding for 24 and 36 h. This result confirmed that the PANI coating is nontoxic to PC 12 cells. The electrical stimulation for 1, 2, and 4 h significantly enhanced the cell numbers for both PANI and ITO conducting surfaces. Moreover, the application of electrical stimulation also improved the neurite outgrowth of PC 12 cells, and the number of PC 12 cells with longer neurite lengths increased obviously under electrical stimulation for the PANI surface. From the mechanism, the adsorption of DMEM proteins was found to be enhanced by electrical stimulation for both PANI/ITO and ITO surfaces. A new band 2 (around 37 kDa) was observed from the collected adsorbed proteins when PC 12 cells were cultured on these surfaces, and culturing PC 12 cells also seemed to increase the amount of band 1 (around 90 kDa). When immersing PANI/ITO and ITO surfaces in a DMEM medium without a cell culture, the number of band 3 (around 70 kDa) and band 4 (around 45 kDa) proteins decreased compared to that of PC 12 cell cultured surfaces. These results are valuable for the design and improvement of the material performance for neural regeneration.

Pure neuritic leprosy presenting as ulnar nerve neuropathy: a case report of electrodiagnostic, radiographic, and histopathological findings.

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Payne, Russell; Baccon, Jennifer; Dossett, John; Scollard, David; Byler, Debra; Patel, Akshal; Harbaugh, Kimberly

2015-11-01

Hansen's disease, or leprosy, is a chronic infectious disease with many manifestations. Though still a major health concern and leading cause of peripheral neuropathy in the developing world, it is rare in the United States, with only about 150 cases reported each year. Nevertheless, it is imperative that neurosurgeons consider it in the differential diagnosis of neuropathy. The causative organism is Mycobacterium leprae, which infects and damages Schwann cells in the peripheral nervous system, leading first to sensory and then to motor deficits. A rare presentation of Hansen's disease is pure neuritic leprosy. It is characterized by nerve involvement without the characteristic cutaneous stigmata. The authors of this report describe a case of pure neuritic leprosy presenting as ulnar nerve neuropathy with corresponding radiographic, electrodiagnostic, and histopathological data. This 11-year-old, otherwise healthy male presented with progressive right-hand weakness and numbness with no cutaneous abnormalities. Physical examination and electrodiagnostic testing revealed findings consistent with a severe ulnar neuropathy at the elbow. Magnetic resonance imaging revealed diffuse thickening and enhancement of the ulnar nerve and narrowing at the cubital tunnel. The patient underwent ulnar nerve decompression with biopsy. Pathology revealed acid-fast organisms within the nerve, which was pathognomonic for Hansen's disease. He was started on antibiotic therapy, and on follow-up he had improved strength and sensation in the ulnar nerve distribution. Pure neuritic leprosy, though rare in the United States, should be considered in the differential diagnosis of those presenting with peripheral neuropathy and a history of travel to leprosy-endemic areas. The long incubation period of M. leprae, the ability of leprosy to mimic other conditions, and the low sensitivity of serological tests make clinical, electrodiagnostic, and radiographic evaluation necessary for diagnosis

Moringa oleifera with promising neuronal survival and neurite outgrowth promoting potentials.

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Hannan, Md Abdul; Kang, Ji-Young; Mohibbullah, Md; Hong, Yong-Ki; Lee, Hyunsook; Choi, Jae-Suk; Choi, In Soon; Moon, Il Soo

2014-02-27

Moringa oleifera Lam. (Moringaceae) by virtue of its high nutritional as well as ethnomedical values has been gaining profound interest both in nutrition and medicinal research. The leaf of this plant is used in ayurvedic medicine to treat paralysis, nervous debility and other nerve disorders. In addition, research evidence also suggests the nootropic as well as neuroprotective roles of Moringa oleifera leaf in animal models. The aim of the present study was to evaluate the effect of Moringa oleifera leaf in the primary hippocampal neurons regarding its neurotrophic and neuroprotective properties. The primary culture of embryonic hippocampal neurons was incubated with the ethanol extract of Moringa oleifera leaf (MOE). After an indicated time, cultures were either stained directly with a lipophilic dye, DiO, or fixed and immunolabeled to visualize the neuronal morphology. Morphometric analyses for neurite maturation and synaptogenesis were performed using Image J software. Neuronal viability was evaluated using trypan blue exclusion and lactate dehydrogenase assays. MOE promoted neurite outgrowth in a concentration-dependent manner with an optimal concentration of 30 μg/mL. As a very initial effect, MOE significantly promoted the earlier stages of neuronal differentiation. Subsequently, MOE significantly increased the number and length of dendrites, the length of axon, and the number and length of both dendrite and axonal branches, and eventually facilitated synaptogenesis. The β-carotene, one major compound of MOE, promoted neuritogensis, but the increase was not comparable with the effect of MOE. In addition, MOE supported neuronal survival by protecting neurons from naturally occurring cell death in vitro. Our findings indicate that MOE promotes axodendritic maturation as well as provides neuroprotection suggesting a promising pharmacological importance of this nutritionally and ethnomedically important plant for the well-being of nervous system. Copyright �

Type I bHLH Proteins Daughterless and Tcf4 Restrict Neurite Branching and Synapse Formation by Repressing Neurexin in Postmitotic Neurons

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Mitchell D’Rozario

2016-04-01

Full Text Available Proneural proteins of the class I/II basic-helix-loop-helix (bHLH family are highly conserved transcription factors. Class I bHLH proteins are expressed in a broad number of tissues during development, whereas class II bHLH protein expression is more tissue restricted. Our understanding of the function of class I/II bHLH transcription factors in both invertebrate and vertebrate neurobiology is largely focused on their function as regulators of neurogenesis. Here, we show that the class I bHLH proteins Daughterless and Tcf4 are expressed in postmitotic neurons in Drosophila melanogaster and mice, respectively, where they function to restrict neurite branching and synapse formation. Our data indicate that Daughterless performs this function in part by restricting the expression of the cell adhesion molecule Neurexin. This suggests a role for these proteins outside of their established roles in neurogenesis.

Electrically conductive biodegradable polymer composite for nerve regeneration: electricity-stimulated neurite outgrowth and axon regeneration.

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Zhang, Ze; Rouabhia, Mahmoud; Wang, Zhaoxu; Roberge, Christophe; Shi, Guixin; Roche, Phillippe; Li, Jiangming; Dao, Lê H

2007-01-01

Normal and electrically stimulated PC12 cell cultures and the implantation of nerve guidance channels were performed to evaluate newly developed electrically conductive biodegradable polymer composites. Polypyrrole (PPy) doped by butane sulfonic acid showed a significantly higher number of viable cells compared with PPy doped by polystyrenesulfonate after a 6-day culture. The PC12 cells were left to proliferate for 6 days, and the PPy-coated membranes, showing less initial cell adherence, recorded the same proliferation rate as did the noncoated membranes. Direct current electricity at various intensities was applied to the PC12 cell-cultured conductive membranes. After 7 days, the greatest number of neurites appeared on the membranes with a current intensity approximating 1.7-8.4 microA/cm. Nerve guidance channels made of conductive biodegradable composite were implanted into rats to replace 8 mm of sciatic nerve. The implants were harvested after 2 months and analyzed with immunohistochemistry and transmission electron microscopy. The regenerated nerve tissue displayed myelinated axons and Schwann cells that were similar to those in the native nerve. Electrical stimulation applied through the electrically conductive biodegradable polymers therefore enhanced neurite outgrowth in a current-dependent fashion. The conductive polymers also supported sciatic nerve regeneration in rats.

Neurite outgrowth stimulatory effects of culinary-medicinal mushrooms and their toxicity assessment using differentiating Neuro-2a and embryonic fibroblast BALB/3T3.

Science.gov (United States)

Phan, Chia-Wei; David, Pamela; Naidu, Murali; Wong, Kah-Hui; Sabaratnam, Vikineswary

2013-10-11

Mushrooms are not only regarded as gourmet cuisine but also as therapeutic agent to promote cognition health. However, little toxicological information is available regarding their safety. Therefore, the aim of this study was to screen selected ethno-pharmacologically important mushrooms for stimulatory effects on neurite outgrowth and to test for any cytotoxicity. The stimulatory effect of mushrooms on neurite outgrowth was assessed in differentiating mouse neuroblastoma (N2a) cells. Neurite length was measured using Image-Pro Insight processor system. Neuritogenesis activity was further validated by fluorescence immunocytochemical staining of neurofilaments. In vitro cytotoxicity was investigated by using mouse embryonic fibroblast (BALB/3T3) and N2a cells for any embryo- and neuro-toxic effects; respectively. Aqueous extracts of Ganoderma lucidum, Lignosus rhinocerotis, Pleurotus giganteus and Grifola frondosa; as well as an ethanol extract of Cordyceps militaris significantly (p effects following 24 h exposure of N2a and 3T3 cells to mushroom extracts. Our results indicate that G. lucidum, L. rhinocerotis, P. giganteus, G. frondosa and C. militaris may be developed as safe and healthy dietary supplements for brain and cognitive health.

Focal adhesion kinase regulates neuronal growth, synaptic plasticity and hippocampus-dependent spatial learning and memory.

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Monje, Francisco J; Kim, Eun-Jung; Pollak, Daniela D; Cabatic, Maureen; Li, Lin; Baston, Arthur; Lubec, Gert

2012-01-01

The focal adhesion kinase (FAK) is a non-receptor tyrosine kinase abundantly expressed in the mammalian brain and highly enriched in neuronal growth cones. Inhibitory and facilitatory activities of FAK on neuronal growth have been reported and its role in neuritic outgrowth remains controversial. Unlike other tyrosine kinases, such as the neurotrophin receptors regulating neuronal growth and plasticity, the relevance of FAK for learning and memory in vivo has not been clearly defined yet. A comprehensive study aimed at determining the role of FAK in neuronal growth, neurotransmitter release and synaptic plasticity in hippocampal neurons and in hippocampus-dependent learning and memory was therefore undertaken using the mouse model. Gain- and loss-of-function experiments indicated that FAK is a critical regulator of hippocampal cell morphology. FAK mediated neurotrophin-induced neuritic outgrowth and FAK inhibition affected both miniature excitatory postsynaptic potentials and activity-dependent hippocampal long-term potentiation prompting us to explore the possible role of FAK in spatial learning and memory in vivo. Our data indicate that FAK has a growth-promoting effect, is importantly involved in the regulation of the synaptic function and mediates in vivo hippocampus-dependent spatial learning and memory. Copyright © 2011 S. Karger AG, Basel.

HDAC up-regulation in early colon field carcinogenesis is involved in cell tumorigenicity through regulation of chromatin structure.

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Yolanda Stypula-Cyrus

Full Text Available Normal cell function is dependent on the proper maintenance of chromatin structure. Regulation of chromatin structure is controlled by histone modifications that directly influence chromatin architecture and genome function. Specifically, the histone deacetylase (HDAC family of proteins modulate chromatin compaction and are commonly dysregulated in many tumors, including colorectal cancer (CRC. However, the role of HDAC proteins in early colorectal carcinogenesis has not been previously reported. We found HDAC1, HDAC2, HDAC3, HDAC5, and HDAC7 all to be up-regulated in the field of human CRC. Furthermore, we observed that HDAC2 up-regulation is one of the earliest events in CRC carcinogenesis and observed this in human field carcinogenesis, the azoxymethane-treated rat model, and in more aggressive colon cancer cell lines. The universality of HDAC2 up-regulation suggests that HDAC2 up-regulation is a novel and important early event in CRC, which may serve as a biomarker. HDAC inhibitors (HDACIs interfere with tumorigenic HDAC activity; however, the precise mechanisms involved in this process remain to be elucidated. We confirmed that HDAC inhibition by valproic acid (VPA targeted the more aggressive cell line. Using nuclease digestion assays and transmission electron microscopy imaging, we observed that VPA treatment induced greater changes in chromatin structure in the more aggressive cell line. Furthermore, we used the novel imaging technique partial wave spectroscopy (PWS to quantify nanoscale alterations in chromatin. We noted that the PWS results are consistent with the biological assays, indicating a greater effect of VPA treatment in the more aggressive cell type. Together, these results demonstrate the importance of HDAC activity in early carcinogenic events and the unique role of higher-order chromatin structure in determining cell tumorigenicity.

Co-effects of matrix low elasticity and aligned topography on stem cell neurogenic differentiation and rapid neurite outgrowth.

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Yao, Shenglian; Liu, Xi; Yu, Shukui; Wang, Xiumei; Zhang, Shuming; Wu, Qiong; Sun, Xiaodan; Mao, Haiquan

2016-05-21

The development of novel biomaterials that deliver precise regulatory signals to direct stem cell fate for nerve regeneration is the focus of current intensive research efforts. In this study, a hierarchically aligned fibrillar fibrin hydrogel (AFG) that was fabricated through electrospinning and the concurrent molecular self-assembly process mimics both the soft and oriented features of nerve tissue, thus providing hybrid biophysical cues to instruct cell behavior in vitro and in vivo. The electrospun hydrogels were examined by scanning electron microscopy (SEM), polarized light microscopy, small angle X-ray scattering assay and atomic force microscopy (AFM), showing a hierarchically linear-ordered structure from the nanoscale to the macroscale with a soft elastic character (elasticity ∼1 kPa). We found that this low elasticity and aligned topography of AFG exhibit co-effects on promoting the neurogenic differentiation of human umbilical cord mesenchymal stem cells (hUMSCs) in comparison to random fibrin hydrogel (RFG) and tissue culture plate (TCP) control after two week cell culture in growth medium lacking supplementation with soluble neurogenic induction factors. In addition, AFG also induces dorsal root ganglion (DRG) neurons to rapidly project numerous long neurite outgrowths longitudinally along the AFG fibers for a total neurite extension distance of 1.96 mm in three days in the absence of neurotrophic factor supplementation. Moreover, the AFG implanted in a rat T9 dorsal hemisection spinal cord injury model was found to promote endogenous neural cell fast migration and axonal invasion along AFG fibers, resulting in aligned tissue cables in vivo. Our results suggest that matrix stiffness and aligned topography may instruct stem cell neurogenic differentiation and rapid neurite outgrowth, providing great promise for biomaterial design for applications in nerve regeneration.

Nerve growth factor alters microtubule targeting agent-induced neurotransmitter release but not MTA-induced neurite retraction in sensory neurons.

Science.gov (United States)

Pittman, Sherry K; Gracias, Neilia G; Fehrenbacher, Jill C

2016-05-01

Peripheral neuropathy is a dose-limiting side effect of anticancer treatment with the microtubule-targeted agents (MTAs), paclitaxel and epothilone B (EpoB); however, the mechanisms by which the MTAs alter neuronal function and morphology are unknown. We previously demonstrated that paclitaxel alters neuronal sensitivity, in vitro, in the presence of nerve growth factor (NGF). Evidence in the literature suggests that NGF may modulate the neurotoxic effects of paclitaxel. Here, we examine whether NGF modulates changes in neuronal sensitivity and morphology induced by paclitaxel and EpoB. Neuronal sensitivity was assessed using the stimulated release of calcitonin gene-related peptide (CGRP), whereas morphology of established neurites was evaluated using a high content screening system. Dorsal root ganglion cultures, maintained in the absence or presence of NGF, were treated from day 7 to day 12 in culture with paclitaxel (300nM) or EpoB (30nM). Following treatment, the release of CGRP was stimulated using capsaicin or high extracellular potassium. In the presence of NGF, EpoB mimicked the effects of paclitaxel: capsaicin-stimulated release was attenuated, potassium-stimulated release was slightly enhanced and the total peptide content was unchanged. In the absence of NGF, both paclitaxel and EpoB decreased capsaicin- and potassium-stimulated release and the total peptide content, suggesting that NGF may reverse MTA-induced hyposensitivity. Paclitaxel and EpoB both decreased neurite length and branching, and this attenuation was unaffected by NGF in the growth media. These differential effects of NGF on neuronal sensitivity and morphology suggest that neurite retraction is not a causative factor to alter neuronal sensitivity. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of sub-lethal neurite outgrowth inhibitory concentrations of chlorpyrifos oxon on cytoskeletal proteins and acetylcholinesterase in differentiating N2a cells

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Flaskos, J., E-mail: flaskos@vet.auth.gr [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Nikolaidis, E. [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Harris, W. [School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom); Sachana, M. [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Hargreaves, A.J., E-mail: alan.hargreaves@ntu.ac.uk [School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom)

2011-11-15

Previous work in our laboratory has shown that sub-lethal concentrations (1-10 {mu}M) of chlorpyrifos (CPF), diazinon (DZ) and diazinon oxon (DZO) inhibit the outgrowth of axon-like neurites in differentiating mouse N2a neuroblastoma cells concomitant with altered levels and/or phosphorylation state of axonal cytoskeleton and growth-associated proteins. The aim of the present work was to determine whether chlorpyrifos oxon (CPO) was capable of inhibiting N2a cell differentiation in a similar manner. Using experimental conditions similar to our previous work, sub-lethal concentrations (1-10 {mu}M) of CPO were found to inhibit N2a cell differentiation. However, unlike previous studies with DZ and DZO, there was a high level of sustained inhibition of acetylcholinesterase (AChE) in CPO treated cells. Impairment of neurite outgrowth was also associated with reduced levels of growth associated protein-43 and neurofilament heavy chain (NFH), and the distribution of NFH in cells stained by indirect immunofluorescence was disrupted. However, in contrast to previous findings for DZO, the absolute level of phosphorylated NFH was unaffected by CPO exposure. Taken together, the findings suggest that sub-lethal concentrations of CPO inhibit axon outgrowth in differentiating N2a cells and that this effect involves reduced levels of two proteins that play key roles in axon outgrowth and maintenance. Although the inhibition of neurite outgrowth is unlikely to involve AChE inhibition directly, further work will help to determine whether the persistent inhibition of AChE by CPO can account for the different effects induced by CPO and DZO on the levels of total and phosphorylated NFH. -- Highlights: Black-Right-Pointing-Pointer Sub-lethal levels of chlorpyrifos oxon inhibit neurite outgrowth in N2a cells Black-Right-Pointing-Pointer Acetylcholinesterase exhibits sustained inhibition throughout exposure Black-Right-Pointing-Pointer The levels of neurofilament heavy chain and GAP-43

Effects of sub-lethal neurite outgrowth inhibitory concentrations of chlorpyrifos oxon on cytoskeletal proteins and acetylcholinesterase in differentiating N2a cells

International Nuclear Information System (INIS)

Flaskos, J.; Nikolaidis, E.; Harris, W.; Sachana, M.; Hargreaves, A.J.

2011-01-01

Previous work in our laboratory has shown that sub-lethal concentrations (1–10 μM) of chlorpyrifos (CPF), diazinon (DZ) and diazinon oxon (DZO) inhibit the outgrowth of axon-like neurites in differentiating mouse N2a neuroblastoma cells concomitant with altered levels and/or phosphorylation state of axonal cytoskeleton and growth-associated proteins. The aim of the present work was to determine whether chlorpyrifos oxon (CPO) was capable of inhibiting N2a cell differentiation in a similar manner. Using experimental conditions similar to our previous work, sub-lethal concentrations (1–10 μM) of CPO were found to inhibit N2a cell differentiation. However, unlike previous studies with DZ and DZO, there was a high level of sustained inhibition of acetylcholinesterase (AChE) in CPO treated cells. Impairment of neurite outgrowth was also associated with reduced levels of growth associated protein-43 and neurofilament heavy chain (NFH), and the distribution of NFH in cells stained by indirect immunofluorescence was disrupted. However, in contrast to previous findings for DZO, the absolute level of phosphorylated NFH was unaffected by CPO exposure. Taken together, the findings suggest that sub-lethal concentrations of CPO inhibit axon outgrowth in differentiating N2a cells and that this effect involves reduced levels of two proteins that play key roles in axon outgrowth and maintenance. Although the inhibition of neurite outgrowth is unlikely to involve AChE inhibition directly, further work will help to determine whether the persistent inhibition of AChE by CPO can account for the different effects induced by CPO and DZO on the levels of total and phosphorylated NFH. -- Highlights: ► Sub-lethal levels of chlorpyrifos oxon inhibit neurite outgrowth in N2a cells ► Acetylcholinesterase exhibits sustained inhibition throughout exposure ► The levels of neurofilament heavy chain and GAP-43 protein are reduced ► Neurofilament heavy chain forms aggregates in cell

Naftidrofuryl affects neurite regeneration by injured adult auditory neurons.

Science.gov (United States)

Lefebvre, P P; Staecker, H; Moonen, G; van de Water, T R

1993-07-01

Afferent auditory neurons are essential for the transmission of auditory information from Corti's organ to the central auditory pathway. Auditory neurons are very sensitive to acute insult and have a limited ability to regenerate injured neuronal processes. Therefore, these neurons appear to be a limiting factor in restoration of hearing function following an injury to the peripheral auditory receptor. In a previous study nerve growth factor (NGF) was shown to stimulate neurite repair but not survival of injured auditory neurons. In this study, we have demonstrated a neuritogenesis promoting effect of naftidrofuryl in an vitro model for injury to adult auditory neurons, i.e. dissociated cell cultures of adult rat spiral ganglia. Conversely, naftidrofuryl did not have any demonstrable survival promoting effect on these in vitro preparations of injured auditory neurons. The potential uses of this drug as a therapeutic agent in acute diseases of the inner ear are discussed in the light of these observations.

A Subset of Autism-Associated Genes Regulate the Structural Stability of Neurons

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Lin, Yu-Chih; Frei, Jeannine A.; Kilander, Michaela B. C.; Shen, Wenjuan; Blatt, Gene J.

2016-01-01

Autism spectrum disorder (ASD) comprises a range of neurological conditions that affect individuals’ ability to communicate and interact with others. People with ASD often exhibit marked qualitative difficulties in social interaction, communication, and behavior. Alterations in neurite arborization and dendritic spine morphology, including size, shape, and number, are hallmarks of almost all neurological conditions, including ASD. As experimental evidence emerges in recent years, it becomes clear that although there is broad heterogeneity of identified autism risk genes, many of them converge into similar cellular pathways, including those regulating neurite outgrowth, synapse formation and spine stability, and synaptic plasticity. These mechanisms together regulate the structural stability of neurons and are vulnerable targets in ASD. In this review, we discuss the current understanding of those autism risk genes that affect the structural connectivity of neurons. We sub-categorize them into (1) cytoskeletal regulators, e.g., motors and small RhoGTPase regulators; (2) adhesion molecules, e.g., cadherins, NCAM, and neurexin superfamily; (3) cell surface receptors, e.g., glutamatergic receptors and receptor tyrosine kinases; (4) signaling molecules, e.g., protein kinases and phosphatases; and (5) synaptic proteins, e.g., vesicle and scaffolding proteins. Although the roles of some of these genes in maintaining neuronal structural stability are well studied, how mutations contribute to the autism phenotype is still largely unknown. Investigating whether and how the neuronal structure and function are affected when these genes are mutated will provide insights toward developing effective interventions aimed at improving the lives of people with autism and their families. PMID:27909399

Regulation of motor proteins, axonal transport deficits and adult-onset neurodegenerative diseases.

Science.gov (United States)

Brady, Scott T; Morfini, Gerardo A

2017-09-01

Neurons affected in a wide variety of unrelated adult-onset neurodegenerative diseases (AONDs) typically exhibit a "dying back" pattern of degeneration, which is characterized by early deficits in synaptic function and neuritic pathology long before neuronal cell death. Consistent with this observation, multiple unrelated AONDs including Alzheimer's disease, Parkinson's disease, Huntington's disease, and several motor neuron diseases feature early alterations in kinase-based signaling pathways associated with deficits in axonal transport (AT), a complex cellular process involving multiple intracellular trafficking events powered by microtubule-based motor proteins. These pathogenic events have important therapeutic implications, suggesting that a focus on preservation of neuronal connections may be more effective to treat AONDs than addressing neuronal cell death. While the molecular mechanisms underlying AT abnormalities in AONDs are still being analyzed, evidence has accumulated linking those to a well-established pathological hallmark of multiple AONDs: altered patterns of neuronal protein phosphorylation. Here, we present a short overview on the biochemical heterogeneity of major motor proteins for AT, their regulation by protein kinases, and evidence revealing cell type-specific AT specializations. When considered together, these findings may help explain how independent pathogenic pathways can affect AT differentially in the context of each AOND. Copyright © 2017 Elsevier Inc. All rights reserved.

MiRNA-mediated regulation of cell signaling and homeostasis in the early mouse embryo.

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Pernaute, Barbara; Spruce, Thomas; Rodriguez, Tristan A; Manzanares, Miguel

2011-02-15

At the time of implantation the mouse embryo is composed of three tissues the epiblast, trophectoderm and primitive endoderm. As development progresses the epiblast goes on to form the foetus whilst the trophectoderm and primitive endoderm give rise to extra-embryonic structures with important roles in embryo patterning and nutrition. Dramatic changes in gene expression occur during early embryo development and these require regulation at different levels. miRNAs are small non coding RNAs that have emerged over the last decade as important post-transcriptional repressors of gene expression. The roles played by miRNAs during early mammalian development are only starting to be elucidated. In order to gain insight into the function of miRNAs in the different lineages of the early mouse embryo we have analysed in depth the phenotype of embryos and extra-embryonic stem cells mutant for the miRNA maturation protein Dicer. This study revealed that miRNAs are involved in regulating cell signaling and homeostasis in the early embryo. Specifically, we identified a role for miRNAs in regulating the Erk signaling pathway in the extra-embryonic endoderm, cell cycle progression in extra-embryonic tissues and apoptosis in the epiblast.

AMP N1-Oxide, a Unique Compound of Royal Jelly, Induces Neurite Outgrowth from PC12 Vells via Signaling by Protein Kinase A Independent of that by Mitogen-Activated Protein Kinase

Directory of Open Access Journals (Sweden)

Noriko Hattori

2010-01-01

Full Text Available Earlier we identified adenosine monophosphate (AMP N1-oxide as a unique compound of royal jelly (RJ that induces neurite outgrowth (neuritegenesis from cultured rat pheochromocytoma PC12 cells via the adenosine A2A receptor. Now, we found that AMP N1-oxide stimulated the phosphorylation of not only mitogen-activated protein kinase (MAPK but also that of cAMP/calcium-response element-binding protein (CREB in a dose-dependent manner. Inhibition of MAPK activation by a MEK inhibitor, PD98059, did not influence the AMP N1-oxide-induced neuritegenesis, whereas that of protein kinase A (PKA by a selective inhibitor, KT5720, significantly reduced neurite outgrowth. AMP N1-oxide also had the activity of suppressing the growth of PC12 cells, which correlated well with the neurite outgrowth-promoting activity. KT5720 restored the growth of AMP N1-oxide-treated PC12 cells. It is well known that nerve growth factor suppresses proliferation of PC12 cells before causing stimulation of neuronal differentiation. Thus, AMP N1-oxide elicited neuronal differentiation of PC12 cells, as evidenced by generation of neurites, and inhibited cell growth through adenosine A2A receptor-mediated PKA signaling, which may be responsible for characteristic actions of RJ.

Chemical Constituents from Hericium erinaceus Promote Neuronal Survival and Potentiate Neurite Outgrowth via the TrkA/Erk1/2 Pathway.

Science.gov (United States)

Zhang, Cheng-Chen; Cao, Chen-Yu; Kubo, Miwa; Harada, Kenichi; Yan, Xi-Tao; Fukuyama, Yoshiyasu; Gao, Jin-Ming

2017-07-30

Hericium erinaceus is a culinary-medicinal mushroom used traditionally in Eastern Asia to improve memory. In this work, we investigated the neuroprotective and neuritogenic effects of the secondary metabolites isolated from the MeOH extract of cultured mycelium of H. erinaceus and the primary mechanisms involved. One new dihydropyridine compound ( 6 ) and one new natural product ( 2 ) together with five known compounds ( 1 , 3 - 5 , 7 ) were obtained and their structures were elucidated by spectroscopic analysis, including 2D NMR and HRMS. The cell-based screening for bioactivity showed that 4-chloro-3,5-dimethoxybenzoic methyl ester ( 1 ) and a cyathane diterpenoid, erincine A ( 3 ), not only potentiated NGF-induced neurite outgrowth but also protected neuronally-differentiated cells against deprivation of NGF in PC12 pheochromocytoma cells. Additionally, compound 3 induced neuritogenesis in primary rat cortex neurons. Furthermore, our results revealed that TrkA-mediated and Erk1/2-dependant pathways could be involved in 1 and 3 -promoted NGF-induced neurite outgrowth in PC12 cells.

Moving to the Beat: Using Music, Rhythm, and Movement to Enhance Self-Regulation in Early Childhood Classrooms

Science.gov (United States)

Williams, Kate E.

2018-01-01

Differences in early self-regulation skills contribute to disparities in success in early learning and school transition, as well as in childhood well-being. Self-regulation refers to managing emotional, cognitive, and behavioral processes that are conducive to positive adjustment and social relationships. Researchers have identified that various…

Predictors of Behavioral Regulation in Kindergarten: Household Chaos, Parenting, and Early Executive Functions

Science.gov (United States)

Vernon-Feagans, Lynne; Garrett-Peters, Patricia; Willoughby, Michael

2016-01-01

Behavioral regulation is an important school readiness skill that has been linked to early executive function (EF) and later success in learning and school achievement. Although poverty and related risks, as well as negative parenting, have been associated with poorer EF and behavioral regulation, chaotic home environments may also play a role in…

Regulation of fertilization and early seed development.

Science.gov (United States)

Dresselhaus, Thomas; Doughty, James

2014-04-01

Plant reproduction meetings often deal either with pre-fertilization processes such as flowering and pollen biology or post-fertilization processes such as embryogenesis and seed development. The Biochemical Society Focused Meeting entitled 'Regulation of Fertilization and Early Seed Development' was organized to close this gap and to discuss mechanistic similarities and future research directions in the reproductive processes shortly before, during and after fertilization. As an outcome of the workshop, invited speakers and a few selected oral communication presenters contributed focused reviews and technical articles for this issue of Biochemical Society Transactions. We provide here a short overview of the contents and highlights of the various articles.

Transcriptional factor PU.1 regulates decidual C1q expression in early pregnancy in human

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Priyaa Madhukaran Raj

2015-02-01

Full Text Available C1q is the first recognition subcomponent of the complement classical pathway, which in addition to being synthesized in the liver, is also expressed by macrophages and dendritic cells. Trophoblast invasion during early placentation results in accumulation of debris that triggers the complement system. Hence, both early and late components of the classical pathway are widely distributed in the placenta and decidua. In addition, C1q has recently been shown to significantly contribute to feto-maternal tolerance, trophoblast migration, and spiral artery remodeling, although the exact mechanism remains unknown. Pregnancy in mice, genetically deficient in C1q, mirrors symptoms similar to that of human preeclampsia. Thus, regulated complement activation has been proposed as an essential requirement for normal successful pregnancy. Little is known about the molecular pathways that regulate C1q expression in pregnancy. PU.1, an Ets-family transcription factor, is required for the development of hematopoietic myeloid lineage immune cells, and its expression is tissue- specific. Recently, PU.1 has been shown to regulate C1q gene expression in dendritic cells and macrophages. Here, we have examined if PU.1 transcription factor regulates decidual C1q expression. We used immune-histochemical analysis, PCR and immunostaining to localize and study the gene expression of PU.1 transcription factor in early human decidua. PU.1 was highly expressed at gene and protein level in early human decidual cells including trophoblast and stromal cells. Surprisingly, nuclear as well as cytoplasmic PU.1 expression was observed. Decidual cells with predominantly nuclear PU.1 expression had higher C1q expression. It is likely that nuclear and cytoplasmic PU.1 localization has a role to play in early pregnancy via regulating C1q expression in the decidua during implantation.

An Early Years Toolbox for Assessing Early Executive Function, Language, Self-Regulation, and Social Development: Validity, Reliability, and Preliminary Norms.

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Howard, Steven J; Melhuish, Edward

2017-06-01

Several methods of assessing executive function (EF), self-regulation, language development, and social development in young children have been developed over previous decades. Yet new technologies make available methods of assessment not previously considered. In resolving conceptual and pragmatic limitations of existing tools, the Early Years Toolbox (EYT) offers substantial advantages for early assessment of language, EF, self-regulation, and social development. In the current study, results of our large-scale administration of this toolbox to 1,764 preschool and early primary school students indicated very good reliability, convergent validity with existing measures, and developmental sensitivity. Results were also suggestive of better capture of children's emerging abilities relative to comparison measures. Preliminary norms are presented, showing a clear developmental trajectory across half-year age groups. The accessibility of the EYT, as well as its advantages over existing measures, offers considerably enhanced opportunities for objective measurement of young children's abilities to enable research and educational applications.

Perceived maternal autonomy-support and early adolescent emotion regulation: a longitudinal study

OpenAIRE

Brenning, Katrijn; Soenens, Bart; Van Petegem, Stijn; Vansteenkiste, Maarten

2015-01-01

This study investigated longitudinal associations between perceived maternal autonomy-supportive parenting and early adolescents' use of three emotion regulation (ER) styles: emotional integration, suppressive regulation, and dysregulation. We tested whether perceived maternal autonomy support predicted changes in ER and whether these ER styles, in turn, related to changes in adjustment (i.e., depressive symptoms, self-esteem). Participants (N= 311, mean age at Time 1 = 12.04) reported on per...

Neural cell adhesion molecule-stimulated neurite outgrowth depends on activation of protein kinase C and the Ras-mitogen-activated protein kinase pathway

DEFF Research Database (Denmark)

Kolkova, K; Novitskaya, V; Pedersen, N

2000-01-01

, inhibitors of the nonreceptor tyrosine kinase p59(fyn), PLC, PKC and MEK and an activator of PKC, phorbol-12-myristate-13-acetate (PMA). MEK2 transfection rescued cells treated with all inhibitors. The same was found for PMA treatment, except when cells concomitantly were treated with the MEK inhibitor....... Arachidonic acid rescued cells treated with antibodies to the FGF receptor or the PLC inhibitor, but not cells in which the activity of PKC, p59(fyn), FAK, Ras, or MEK was inhibited. Interaction of NCAM with a synthetic NCAM peptide ligand, known to induce neurite outgrowth, was shown to stimulate...... phosphorylation of the MAP kinases extracellular signal-regulated kinases ERK1 and ERK2. The MAP kinase activation was sustained, because ERK1 and ERK2 were phosphorylated in PC12-E2 cells and primary hippocampal neurons even after 24 hr of cultivation on NCAM-expressing fibroblasts. Based on these results, we...

CSK negatively regulates nerve growth factor induced neural differentiation and augments AKT kinase activity

International Nuclear Information System (INIS)

Dey, Nandini; Howell, Brian W.; De, Pradip K.; Durden, Donald L.

2005-01-01

Src family kinases are involved in transducing growth factor signals for cellular differentiation and proliferation in a variety of cell types. The activity of all Src family kinases (SFKs) is controlled by phosphorylation at their C-terminal 527-tyrosine residue by C-terminal SRC kinase, CSK. There is a paucity of information regarding the role of CSK and/or specific Src family kinases in neuronal differentiation. Pretreatment of PC12 cells with the Src family kinase inhibitor, PP1, blocked NGF-induced activation of SFKs and obliterated neurite outgrowth. To confirm a role for CSK and specific isoforms of SFKs in neuronal differentiation, we overexpressed active and catalytically dead CSK in the rat pheochromocytoma cell line, PC12. CSK overexpression caused a profound inhibition of NGF-induced activation of FYN, YES, RAS, and ERK and inhibited neurite outgrowth, NGF-stimulated integrin-directed migration and blocked the NGF-induced conversion of GDP-RAC to its GTP-bound active state. CSK overexpression markedly augmented the activation state of AKT following NGF stimulation. In contrast, kinase-dead CSK augmented the activation of FYN, RAS, and ERK and increased neurite outgrowth. These data suggest a distinct requirement for CSK in the regulation of NGF/TrkA activation of RAS, RAC, ERK, and AKT via the differential control of SFKs in the orchestration of neuronal differentiation

Differential regulation of collapsin response mediator protein 2 (CRMP2 phosphorylation by GSK3ß and CDK5 following traumatic brain injury

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Sarah Marie Wilson

2014-05-01

Full Text Available Aberrant ion channel function has been heralded as a main underlying mechanism driving epilepsy and its symptoms. However, it has become increasingly clear that treatment strategies targeting voltage-gated sodium or calcium channels merely mask the symptoms of epilepsy without providing disease-modifying benefits. Ion channel function is likely only one important cog in a highly complex machine. Gross morphological changes, such as reactive sprouting and outgrowth, may also play a role in epileptogenesis. Mechanisms responsible for these changes are not well understood. Here we investigate the potential involvement of the neurite outgrowth-promoting molecule collapsin response mediator protein 2 (CRMP2. CRMP2 activity, in this respect, is regulated by phosphorylation state, where phosphorylation by a variety of kinases, including glycogen synthase kinase 3 β (GSK3β renders it inactive. Phosphorylation (inactivation of CRMP2 was decreased at two distinct phases following traumatic brain injury (TBI. While reduced CRMP2 phosphorylation during the early phase was attributed to the inactivation of GSK3β, the sustained decrease in CRMP2 phosphorylation in the late phase appeared to be independent of GSK3β activity. Instead, the reduction in GSK3β-phosphorylated CRMP2 was attributed to a loss of priming by cyclin-dependent kinase 5 (CDK5, which allows for subsequent phosphorylation by GSK3β. Based on the observation that the proportion of active CRMP2 is increased for up to 4 weeks following TBI, it was hypothesized that it may drive neurite outgrowth, and therefore, circuit reorganization during this time. Therefore, a novel small-molecule tool was used to target CRMP2 in an attempt to determine its importance in mossy fiber sprouting following TBI. In this report, we demonstrate novel differential regulation of CRMP2 phosphorylation by GSK3β and CDK5 following TBI.

Application of neurite orientation dispersion and density imaging (NODDI) to a tau pathology model of Alzheimer's disease.

LENUS (Irish Health Repository)

Colgan, N

2015-10-23

Increased hyperphosphorylated tau and the formation of intracellular neurofibrillary tangles are associated with the loss of neurons and cognitive decline in Alzheimer\\'s disease, and related neurodegenerative conditions. We applied two diffusion models, diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI), to in vivo diffusion magnetic resonance images (dMRI) of a mouse model of human tauopathy (rTg4510) at 8.5months of age. In grey matter regions with the highest degree of tau burden, microstructural indices provided by both NODDI and DTI discriminated the rTg4510 (TG) animals from wild type (WT) controls; however only the neurite density index (NDI) (the volume fraction that comprises axons or dendrites) from the NODDI model correlated with the histological measurements of the levels of hyperphosphorylated tau protein. Reductions in diffusion directionality were observed when implementing both models in the white matter region of the corpus callosum, with lower fractional anisotropy (DTI) and higher orientation dispersion (NODDI) observed in the TG animals. In comparison to DTI, histological measures of tau pathology were more closely correlated with NODDI parameters in this region. This in vivo dMRI study demonstrates that NODDI identifies potential tissue sources contributing to DTI indices and NODDI may provide greater specificity to pathology in Alzheimer\\'s disease.

Enhancement of neurite outgrowth in neuron cancer stem cells by growth on 3-D collagen scaffolds

Energy Technology Data Exchange (ETDEWEB)

Chen, Chih-Hao [Department of Electrical Engineering, I-Shou University, Taiwan, ROC (China); Neurosurgery, Department of Surgery, Kaohsiung Veterans General Hospital, Taiwan, ROC (China); Department of Biomedical Engineering, I-Shou University, Taiwan, ROC (China); Kuo, Shyh Ming [Department of Biomedical Engineering, I-Shou University, Taiwan, ROC (China); Liu, Guei-Sheung [Centre for Eye Research Australia, University of Melbourne (Australia); Chen, Wan-Nan U. [Department of Biological Science and Technology, I-Shou University, Taiwan, ROC (China); Chuang, Chin-Wen [Department of Electrical Engineering, I-Shou University, Taiwan, ROC (China); Liu, Li-Feng, E-mail: liulf@isu.edu.tw [Department of Biological Science and Technology, I-Shou University, Taiwan, ROC (China)

2012-11-09

Highlights: Black-Right-Pointing-Pointer Neuron cancer stem cells (NCSCs) behave high multiply of growth on collagen scaffold. Black-Right-Pointing-Pointer Enhancement of NCSCs neurite outgrowth on porous collagen scaffold. Black-Right-Pointing-Pointer 3-D collagen culture of NCSCs shows an advance differentiation than 2-D culture. -- Abstract: Collagen is one component of the extracellular matrix that has been widely used for constructive remodeling to facilitate cell growth and differentiation. The 3-D distribution and growth of cells within the porous scaffold suggest a clinical significance for nerve tissue engineering. In the current study, we investigated proliferation and differentiation of neuron cancer stem cells (NCSCs) on a 3-D porous collagen scaffold that mimics the natural extracellular matrix. We first generated green fluorescence protein (GFP) expressing NCSCs using a lentiviral system to instantly monitor the transitions of morphological changes during growth on the 3-D scaffold. We found that proliferation of GFP-NCSCs increased, and a single cell mass rapidly grew with unrestricted expansion between days 3 and 9 in culture. Moreover, immunostaining with neuronal nuclei (NeuN) revealed that NCSCs grown on the 3-D collagen scaffold significantly enhanced neurite outgrowth. Our findings confirmed that the 80 {mu}m porous collagen scaffold could enhance attachment, viability and differentiation of the cancer neural stem cells. This result could provide a new application for nerve tissue engineering and nerve regeneration.

Enhancement of neurite outgrowth in neuron cancer stem cells by growth on 3-D collagen scaffolds

International Nuclear Information System (INIS)

Chen, Chih-Hao; Kuo, Shyh Ming; Liu, Guei-Sheung; Chen, Wan-Nan U.; Chuang, Chin-Wen; Liu, Li-Feng

2012-01-01

Highlights: ► Neuron cancer stem cells (NCSCs) behave high multiply of growth on collagen scaffold. ► Enhancement of NCSCs neurite outgrowth on porous collagen scaffold. ► 3-D collagen culture of NCSCs shows an advance differentiation than 2-D culture. -- Abstract: Collagen is one component of the extracellular matrix that has been widely used for constructive remodeling to facilitate cell growth and differentiation. The 3-D distribution and growth of cells within the porous scaffold suggest a clinical significance for nerve tissue engineering. In the current study, we investigated proliferation and differentiation of neuron cancer stem cells (NCSCs) on a 3-D porous collagen scaffold that mimics the natural extracellular matrix. We first generated green fluorescence protein (GFP) expressing NCSCs using a lentiviral system to instantly monitor the transitions of morphological changes during growth on the 3-D scaffold. We found that proliferation of GFP-NCSCs increased, and a single cell mass rapidly grew with unrestricted expansion between days 3 and 9 in culture. Moreover, immunostaining with neuronal nuclei (NeuN) revealed that NCSCs grown on the 3-D collagen scaffold significantly enhanced neurite outgrowth. Our findings confirmed that the 80 μm porous collagen scaffold could enhance attachment, viability and differentiation of the cancer neural stem cells. This result could provide a new application for nerve tissue engineering and nerve regeneration.

A characteristic chondroitin sulfate trisaccharide unit with a sulfated fucose branch exhibits neurite outgrowth-promoting activity: Novel biological roles of fucosylated chondroitin sulfates isolated from the sea cucumber Apostichopus japonicus.

Science.gov (United States)

Shida, Miharu; Mikami, Tadahisa; Tamura, Jun-Ichi; Kitagawa, Hiroshi

2017-06-03

Chondroitin sulfate (CS) is a class of sulfated glycosaminoglycan (GAG) chains that consist of repeating disaccharide unit composed of glucuronic acid (GlcA) and N-acetylgalactosamine (GalNAc). CS chains are found throughout the pericellular and extracellular spaces and contribute to the formation of functional microenvironments for numerous biological events. However, their structure-function relations remain to be fully characterized. Here, a fucosylated CS (FCS) was isolated from the body wall of the sea cucumber Apostichopus japonicus. Its promotional effects on neurite outgrowth were assessed by using isolated polysaccharides and the chemically synthesized FCS trisaccharide β-D-GalNAc(4,6-O-disulfate) (1-4)[α-l-fucose (2,4-O-disulfate) (1-3)]-β-D-GlcA. FCS polysaccharides contained the E-type disaccharide unit GlcA-GalNAc(4,6-O-disulfate) as a CS major backbone structure and carried distinct sulfated fucose branches. Despite their relatively lower abundance of E unit, FCS polysaccharides exhibited neurite outgrowth-promoting activity comparable to squid cartilage-derived CS-E polysaccharides, which are characterized by their predominant E units, suggesting potential roles of the fucose branch in neurite outgrowth. Indeed, the chemically synthesized FCS trisaccharide was as effective as CS-E tetrasaccharide in stimulating neurite elongation in vitro. In conclusion, FCS trisaccharide units with 2,4-O-disulfated fucose branches may provide new insights into understanding the structure-function relations of CS chains. Copyright © 2017 Elsevier Inc. All rights reserved.

Chemical Constituents from Hericium erinaceus Promote Neuronal Survival and Potentiate Neurite Outgrowth via the TrkA/Erk1/2 Pathway

Directory of Open Access Journals (Sweden)

Cheng-Chen Zhang

2017-07-01

Full Text Available Hericium erinaceus is a culinary-medicinal mushroom used traditionally in Eastern Asia to improve memory. In this work, we investigated the neuroprotective and neuritogenic effects of the secondary metabolites isolated from the MeOH extract of cultured mycelium of H. erinaceus and the primary mechanisms involved. One new dihydropyridine compound (6 and one new natural product (2 together with five known compounds (1,3–5,7 were obtained and their structures were elucidated by spectroscopic analysis, including 2D NMR and HRMS. The cell-based screening for bioactivity showed that 4-chloro-3,5-dimethoxybenzoic methyl ester (1 and a cyathane diterpenoid, erincine A (3, not only potentiated NGF-induced neurite outgrowth but also protected neuronally-differentiated cells against deprivation of NGF in PC12 pheochromocytoma cells. Additionally, compound 3 induced neuritogenesis in primary rat cortex neurons. Furthermore, our results revealed that TrkA-mediated and Erk1/2-dependant pathways could be involved in 1 and 3-promoted NGF-induced neurite outgrowth in PC12 cells.

Evaluation of the Preschool Situational Self-Regulation Toolkit (PRSIST) Program for Supporting children's early self-regulation development: study protocol for a cluster randomized controlled trial.

Science.gov (United States)

Howard, Steven J; Vasseleu, Elena; Neilsen-Hewett, Cathrine; Cliff, Ken

2018-01-24

For children with low self-regulation in the preschool years, the likelihood of poorer intellectual, health, wealth and anti-social outcomes in adulthood is overwhelming. Yet this knowledge has not yielded a framework for understanding self-regulatory change, nor generated particularly successful methods for enacting this change. Reconciling insights from cross-disciplinary theory, research and practice, this study seeks to implement a newly developed program of low-cost and routine practices and activities for supporting early self-regulatory development within preschool contexts and to evaluate its effect on children's self-regulation, executive function and school readiness; and educator perceived knowledge, attitudes and self-efficacy related to self-regulation. The Early Start to Self-Regulation study is a cluster randomized, controlled trial for evaluating benefits of the Preschool Situational Self-Regulation Toolkit (PRSIST) program, when implemented by early childhood educators, compared with routine practice. The PRSIST program combines professional learning, adult practices, child activities and connections to the home to support children's self-regulation development. Fifty preschool centers in New South Wales, Australia, will be selected to ensure a range of characteristics, namely: National Quality Standards (NQS) ratings, geographic location and socioeconomic status. After collection of baseline child and educator data, participating centers will then be randomly allocated to one of two groups, stratified by NQS rating: (1) an intervention group (25 centers) that will implement the PRSIST program; or (2) a control group (25 centers) that will continue to engage in practice as usual. Primary outcomes at the child level will be two measures of self-regulation: Head-Toes-Knees-Shoulders task and the PRSIST observational assessment. Secondary outcomes at the child level will be adult-reported measures of child self-regulation, executive function and

Neurite extension and neuronal differentiation of human induced pluripotent stem cell derived neural stem cells on polyethylene glycol hydrogels containing a continuous Young's Modulus gradient.

Science.gov (United States)

Mosley, Matthew C; Lim, Hyun Ju; Chen, Jing; Yang, Yueh-Hsun; Li, Shenglan; Liu, Ying; Smith Callahan, Laura A

2017-03-01

Mechanotransduction in neural cells involves multiple signaling pathways that are not fully understood. Differences in lineage and maturation state are suggested causes for conflicting reports on neural cell mechanosensitivity. To optimize matrices for use in stem cell therapy treatments transplanting human induced pluripotent stem cell derived neural stem cells (hNSC) into lesions after spinal cord injury, the effects of Young's Modulus changes on hNSC behavior must be understood. The present study utilizes polyethylene glycol hydrogels containing a continuous gradient in Young's modulus to examine changes in the Young's Modulus of the culture substrate on hNSC neurite extension and neural differentiation. Changes in the Young's Modulus of the polyethylene glycol hydrogels was found to affect neurite extension and cellular organization on the matrices. hNSC cultured on 907 Pa hydrogels were found to extend longer neurites than hNSC cultured on other tested Young's Moduli hydrogels. The gene expression of β tubulin III and microtubule-associated protein 2 in hNSC was affected by changes in the Young's Modulus of the hydrogel. The combinatory method approach used in the present study demonstrates that hNSC are mechanosensitive and the matrix Young's Modulus should be a design consideration for hNSC transplant applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 824-833, 2017. © 2016 Wiley Periodicals, Inc.

Post-transcriptional regulation of macrophage ABCA1, an early response gene to IFN-γ

International Nuclear Information System (INIS)

Alfaro Leon, Martha Leticia; Evans, Glenn F.; Farmen, Mark W.; Zuckerman, Steven H.

2005-01-01

Interferon-γ (IFN-γ) down-regulates receptors associated with reverse cholesterol transport including ABCA1. In the present study, the kinetics and mechanism of ABCA1 down-regulation were determined in mouse peritoneal macrophages. IFN-γ decreased ABCA1 mRNA 1 h following IFN-γ addition and was maximally reduced by 3 h. Down-regulation was protein synthesis dependent and involved post-transcriptional processes. ABCA1 message had a T 1/2 of 115 min in actinomycin treated cells that was reduced to a T 1/2 of 37 min by IFN-γ. The decrease in message stability was also associated with a rapid loss of ABCA1 protein, significant 3 h following IFN-γ addition. The kinetics of ABCA1 message and protein decrease was consistent with the early IFN-γ-induced changes in Stat1 phosphorylation and nuclear translocation observed in these cells. Therefore, ABCA1 can be considered as an early response gene to macrophage activation by IFN-γ with down-regulation occurring by message destabilization

Emotional and Adrenocortical Regulation in Early Adolescence: Prediction by Attachment Security and Disorganization in Infancy

Science.gov (United States)

Spangler, Gottfried; Zimmermann, Peter

2014-01-01

The aim of the present study was to examine differences in emotion expression and emotion regulation in emotion-eliciting situations in early adolescence from a bio-psycho-social perspective, specifically investigating the influence of early mother-infant attachment and attachment disorganization on behavioural and adrenocortical responses. The…

Immune Regulator MCPIP1 Modulates TET Expression during Early Neocortical Development

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Huihui Jiang

2016-09-01

Full Text Available MCPIP1 is a recently identified immune regulator that plays critical roles in preventing immune disorders, and is also present in the brain. Currently an unresolved question remains as to how MCPIP1 performs its non-immune functions in normal brain development. Here, we report that MCPIP1 is abundant in neural progenitor cells (NPCs and newborn neurons during the early stages of neurogenesis. The suppression of MCPIP1 expression impairs normal neuronal differentiation, cell-cycle exit, and concomitant NPC proliferation. MCPIP1 is important for maintenance of the NPC pool. Notably, we demonstrate that MCPIP1 reduces TET (TET1/TET2/TET3 levels and then decreases 5-hydroxymethylcytosine levels. Furthermore, the MCPIP1 interaction with TETs is involved in neurogenesis and in establishing the proper number of NPCs in vivo. Collectively, our findings not only demonstrate that MCPIP1 plays an important role in early cortical neurogenesis but also reveal an unexpected link between neocortical development, immune regulators, and epigenetic modification.

Regulation of Adult Neurogenesis and Plasticity by (Early) Stress, Glucocorticoids, and Inflammation

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Lucassen, P.J.; Oomen, C.A.; Naninck, E.F.G.; Fitzsimons, C.P.; van Dam, A.M.; Czeh, B.; Korosi, A.

2015-01-01

Exposure to stress is one of the best-known negative regulators of adult neurogenesis (AN). We discuss changes in neurogenesis in relation to exposure to stress, glucocorticoid hormones, and inflammation, with a particular focus on early development and on lasting effects of stress. Although the

The C1 domain-targeted isophthalate derivative HMI-1b11 promotes neurite outgrowth and GAP-43 expression through PKCα activation in SH-SY5Y cells.

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Talman, Virpi; Amadio, Marialaura; Osera, Cecilia; Sorvari, Salla; Boije Af Gennäs, Gustav; Yli-Kauhaluoma, Jari; Rossi, Daniela; Govoni, Stefano; Collina, Simona; Ekokoski, Elina; Tuominen, Raimo K; Pascale, Alessia

2013-07-01

Protein kinase C (PKC) is a family of serine/threonine phosphotransferases ubiquitously expressed and involved in multiple cellular functions, such as proliferation, apoptosis and differentiation. The C1 domain of PKC represents an attractive drug target, especially for developing PKC activators. Dialkyl 5-(hydroxymethyl)isophthalates are a novel group of synthetic C1 domain ligands that exhibit antiproliferative effect in HeLa cervical carcinoma cells. Here we selected two isophthalates, HMI-1a3 and HMI-1b11, and characterized their effects in the human neuroblastoma cell line SH-SY5Y. Both of the active isophthalates exhibited significant antiproliferative and differentiation-inducing effects. Since HMI-1b11 did not impair cell survival even at the highest concentration tested (20μM), and supported neurite growth and differentiation of SH-SY5Y cells, we focused on studying its downstream signaling cascades and effects on gene expression. Consistently, genome-wide gene expression microarray and gene set enrichment analysis indicated that HMI-1b11 (10μM) induced changes in genes mainly related to cell differentiation. In particular, further studies revealed that HMI-1b11 exposure induced up-regulation of GAP-43, a marker for neurite sprouting and neuronal differentiation. These effects were induced by a 7-min HMI-1b11 treatment and specifically depended on PKCα activation, since pretreatment with the selective inhibitor Gö6976 abolished the up-regulation of GAP-43 protein observed at 12h. In parallel, we found that a 7-min exposure to HMI-1b11 induced PKCα accumulation to the cytoskeleton, an effect that was again prevented by pretreatment with Gö6976. Despite similar binding affinities to PKC, the isophthalates had different effects on PKC-dependent ERK1/2 signaling: HMI-1a3-induced ERK1/2 phosphorylation was transient, while HMI-1b11 induced a rapid but prolonged ERK1/2 phosphorylation. Overall our data are in accordance with previous studies showing that

Loss of Aβ-nerve endings associated with the Merkel cell-neurite complex in the lesional oral mucosa epithelium of lichen planus and hyperkeratosis.

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Carrión, Daniela Calderón; Korkmaz, Yüksel; Cho, Britta; Kopp, Marion; Bloch, Wilhelm; Addicks, Klaus; Niedermeier, Wilhelm

2016-03-30

The Merkel cell-neurite complex initiates the perception of touch and mediates Aβ slowly adapting type I responses. Lichen planus is a chronic inflammatory autoimmune disease with T-cell-mediated inflammation, whereas hyperkeratosis is characterized with or without epithelial dysplasia in the oral mucosa. To determine the effects of lichen planus and hyperkeratosis on the Merkel cell-neurite complex, healthy oral mucosal epithelium and lesional oral mucosal epithelium of lichen planus and hyperkeratosis patients were stained by immunohistochemistry (the avidin-biotin-peroxidase complex and double immunofluorescence methods) using pan cytokeratin, cytokeratin 20 (K20, a Merkel cell marker), and neurofilament 200 (NF200, a myelinated Aβ- and Aδ-nerve fibre marker) antibodies. NF200-immunoreactive (ir) nerve fibres in healthy tissues and in the lesional oral mucosa epithelium of lichen planus and hyperkeratosis were counted and statistically analysed. In the healthy oral mucosa, K20-positive Merkel cells with and without close association to the intraepithelial NF200-ir nerve fibres were detected. In the lesional oral mucosa of lichen planus and hyperkeratosis patients, extremely rare NF200-ir nerve fibres were detected only in the lamina propria. Compared with healthy tissues, lichen planus and hyperkeratosis tissues had significantly decreased numbers of NF200-ir nerve fibres in the oral mucosal epithelium. Lichen planus and hyperkeratosis were associated with the absence of Aβ-nerve endings in the oral mucosal epithelium. Thus, we conclude that mechanosensation mediated by the Merkel cell-neurite complex in the oral mucosal epithelium is impaired in lichen planus and hyperkeratosis.

Surface microstructures on planar substrates and textile fibers guide neurite outgrowth: a scaffold solution to push limits of critical nerve defect regeneration?

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Stefan Weigel

Full Text Available The treatment of critical size peripheral nerve defects represents one of the most serious problems in neurosurgery. If the gap size exceeds a certain limit, healing can't be achieved. Connection mismatching may further reduce the clinical success. The present study investigates how far specific surface structures support neurite outgrowth and by that may represent one possibility to push distance limits that can be bridged. For this purpose, growth cone displacement of fluorescent embryonic chicken spinal cord neurons was monitored using time-lapse video. In a first series of experiments, parallel patterns of polyimide ridges of different geometry were created on planar silicon oxide surfaces. These channel-like structures were evaluated with and without amorphous hydrogenated carbon (a-C:H coating. In a next step, structured and unstructured textile fibers were investigated. All planar surface materials (polyimide, silicon oxide and a-C:H proved to be biocompatible, i.e. had no adverse effect on nerve cultures and supported neurite outgrowth. Mean growth cone migration velocity measured on 5 minute base was marginally affected by surface structuring. However, surface structure variability, i.e. ridge height, width and inter-ridge spacing, significantly enhanced the resulting net velocity by guiding the growth cone movement. Ridge height and inter-ridge distance affected the frequency of neurites crossing over ridges. Of the evaluated dimensions ridge height, width, and inter-ridge distance of respectively 3, 10, and 10 µm maximally supported net axon growth. Comparable artificial grooves, fabricated onto the surface of PET fibers by using an excimer laser, showed similar positive effects. Our data may help to further optimize surface characteristics of artificial nerve conduits and bioelectronic interfaces.

Insecure Attachment and Eating Pathology in Early Adolescence: Role of Emotion Regulation

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van Durme, Kim; Braet, Caroline; Goossens, Lien

2015-01-01

The present study investigated whether associations exist between attachment dimensions toward mother and different forms of eating pathology (EP) in a group of early adolescent boys and girls, and whether these associations were mediated by maladaptive emotion regulation (ER) strategies. Developmentally appropriate self-report questionnaires were…

Microenvironments and Signaling Pathways Regulating Early Dissemination, Dormancy, and Metastasis

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2016-09-01

regulators of branching morphogenesis during mammary gland development 17,18, arguing that normal mammary epithelial cells cooperate with these innate ...CD45+CD11b+F4/80+ cells lacking lymphoid and granulocytic markers (Supplementary Fig.3B). viSNE plots 30 of myelo- monocytic cells (Fig.5A) showed that...cancer cells and how the microenvironment in these primary sites named P-TMEM (Primary Tumor Microenvironment of Metastases) contribute to early

From early family systems to internalizing symptoms: The role of emotion regulation and peer relations.

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Lindblom, Jallu; Vänskä, Mervi; Flykt, Marjo; Tolvanen, Asko; Tiitinen, Aila; Tulppala, Maija; Punamäki, Raija-Leena

2017-04-01

Research has demonstrated the importance of early family characteristics, such as the quality of caregiving, on children's later mental health. Information is, however, needed about the role of more holistic family systems and specific child-related socioemotional mechanisms. In this study, we conceptualize families as dynamic family system types, consisting of both marital and parenting trajectories over the transition to parenthood. First, we examine how early family system types predict children's anxiety, depression, peer exclusion, and emotion regulation. Second, we test whether couples' infertility history and other family related contextual factors moderate the effects of family system types on child outcomes. Third, we test whether children's emotion regulation and peer exclusion mediate the effects of family system types on anxiety and depression. The participants were 452 families representing cohesive, distant, authoritative, enmeshed, and discrepant family types, identified on the basis of relationship autonomy and intimacy from pregnancy to the child's age of 2 and 12 months. Children's anxiety, depression, emotion regulation, and peer exclusion were assessed at the age of 7-8 years. Structural equation modeling showed that distant, enmeshed, and discrepant families similarly predicted children's heightened anxiety and depression. Infertility history, parental education, and parity moderated the associations between certain family system types and child outcomes. Finally, emotion regulation, but not peer exclusion, was a common mediating mechanism between distant and enmeshed families and children's depression. The results emphasize the importance of early family environments on children's emotion regulation development and internalizing psychopathology. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

p35 regulates the CRM1-dependent nucleocytoplasmic shuttling of nuclear hormone receptor coregulator-interacting factor 1 (NIF-1.

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Xiao-Su Zhao

Full Text Available Cyclin-dependent kinase 5 (Cdk5 is a proline-directed serine/threonine kinase, which plays critical roles in a wide spectrum of neuronal functions including neuronal survival, neurite outgrowth, and synapse development and plasticity. Cdk5 activity is controlled by its specific activators: p35 or p39. While knockout studies reveal that Cdk5/p35 is critical for neuronal migration during early brain development, functions of Cdk5/p35 have been unraveled through the identification of the interacting proteins of p35, most of which are Cdk5/p35 substrates. However, it remains unclear whether p35 can regulate neuronal functions independent of Cdk5 activity. Here, we report that a nuclear protein, nuclear hormone receptor coregulator (NRC-interacting factor 1 (NIF-1, is a new interacting partner of p35. Interestingly, p35 regulates the functions of NIF-1 independent of Cdk5 activity. NIF-1 was initially discovered as a transcriptional regulator that enhances the transcriptional activity of nuclear hormone receptors. Our results show that p35 interacts with NIF-1 and regulates its nucleocytoplasmic trafficking via the nuclear export pathway. Furthermore, we identified a nuclear export signal on p35; mutation of this site or blockade of the CRM1/exportin-dependent nuclear export pathway resulted in the nuclear accumulation of p35. Intriguingly, blocking the nuclear export of p35 attenuated the nuclear accumulation of NIF-1. These findings reveal a new p35-dependent mechanism in transcriptional regulation that involves the nucleocytoplasmic shuttling of transcription regulators.

p35 regulates the CRM1-dependent nucleocytoplasmic shuttling of nuclear hormone receptor coregulator-interacting factor 1 (NIF-1).

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Zhao, Xiao-Su; Fu, Wing-Yu; Chien, Winnie W Y; Li, Zhen; Fu, Amy K Y; Ip, Nancy Y

2014-01-01

Cyclin-dependent kinase 5 (Cdk5) is a proline-directed serine/threonine kinase, which plays critical roles in a wide spectrum of neuronal functions including neuronal survival, neurite outgrowth, and synapse development and plasticity. Cdk5 activity is controlled by its specific activators: p35 or p39. While knockout studies reveal that Cdk5/p35 is critical for neuronal migration during early brain development, functions of Cdk5/p35 have been unraveled through the identification of the interacting proteins of p35, most of which are Cdk5/p35 substrates. However, it remains unclear whether p35 can regulate neuronal functions independent of Cdk5 activity. Here, we report that a nuclear protein, nuclear hormone receptor coregulator (NRC)-interacting factor 1 (NIF-1), is a new interacting partner of p35. Interestingly, p35 regulates the functions of NIF-1 independent of Cdk5 activity. NIF-1 was initially discovered as a transcriptional regulator that enhances the transcriptional activity of nuclear hormone receptors. Our results show that p35 interacts with NIF-1 and regulates its nucleocytoplasmic trafficking via the nuclear export pathway. Furthermore, we identified a nuclear export signal on p35; mutation of this site or blockade of the CRM1/exportin-dependent nuclear export pathway resulted in the nuclear accumulation of p35. Intriguingly, blocking the nuclear export of p35 attenuated the nuclear accumulation of NIF-1. These findings reveal a new p35-dependent mechanism in transcriptional regulation that involves the nucleocytoplasmic shuttling of transcription regulators.

A low-cost microwell device for high-resolution imaging of neurite outgrowth in 3D

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Ren, Yuan; Mlodzianoski, Michael J.; Cheun Lee, Aih; Huang, Fang; Suter, Daniel M.

2018-06-01

Objective. Current neuronal cell culture is mostly performed on two-dimensional (2D) surfaces, which lack many of the important features of the native environment of neurons, including topographical cues, deformable extracellular matrix, and spatial isotropy or anisotropy in three dimensions. Although three-dimensional (3D) cell culture systems provide a more physiologically relevant environment than 2D systems, their popularity is greatly hampered by the lack of easy-to-make-and-use devices. We aim to develop a widely applicable 3D culture procedure to facilitate the transition of neuronal cultures from 2D to 3D. Approach. We made a simple microwell device for 3D neuronal cell culture that is inexpensive, easy to assemble, and fully compatible with commonly used imaging techniques, including super-resolution microscopy. Main results. We developed a novel gel mixture to support 3D neurite regeneration of Aplysia bag cell neurons, a system that has been extensively used for quantitative analysis of growth cone dynamics in 2D. We found that the morphology and growth pattern of bag cell growth cones in 3D culture closely resemble the ones of growth cones observed in vivo. We demonstrated the capability of our device for high-resolution imaging of cytoskeletal and signaling proteins as well as organelles. Significance. Neuronal cell culture has been a valuable tool for neuroscientists to study the behavior of neurons in a controlled environment. Compared to 2D, neurons cultured in 3D retain the majority of their native characteristics, while offering higher accessibility, control, and repeatability. We expect that our microwell device will facilitate a wider adoption of 3D neuronal cultures to study the mechanisms of neurite regeneration.

No significant regulation of bicoid mRNA by Pumilio or Nanos in the early Drosophila embryo.

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Wharton, Tammy H; Nomie, Krystle J; Wharton, Robin P

2018-01-01

Drosophila Pumilio (Pum) is a founding member of the conserved Puf domain class of RNA-binding translational regulators. Pum binds with high specificity, contacting eight nucleotides, one with each of the repeats in its RNA-binding domain. In general, Pum is thought to block translation in collaboration with Nanos (Nos), which exhibits no binding specificity in isolation but is recruited jointly to regulatory sequences containing a Pum binding site in the 3'-UTRs of target mRNAs. Unlike Pum, which is ubiquitous in the early embryo, Nos is tightly restricted to the posterior, ensuring that repression of its best-characterized target, maternal hunchback (hb) mRNA, takes place exclusively in the posterior. An exceptional case of Nos-independent regulation by Pum has been described-repression of maternal bicoid (bcd) mRNA at the anterior pole of the early embryo, dependent on both Pum and conserved Pum binding sites in the 3'-UTR of the mRNA. We have re-investigated regulation of bcd in the early embryo; our experiments reveal no evidence of a role for Pum or its conserved binding sites in regulation of the perdurance of bcd mRNA or protein. Instead, we find that Pum and Nos control the accumulation of bcd mRNA in testes.

An Early Years Toolbox for Assessing Early Executive Function, Language, Self-Regulation, and Social Development: Validity, Reliability, and Preliminary Norms

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Howard, Steven J.; Melhuish, Edward

2017-01-01

Several methods of assessing executive function (EF), self-regulation, language development, and social development in young children have been developed over previous decades. Yet new technologies make available methods of assessment not previously considered. In resolving conceptual and pragmatic limitations of existing tools, the Early Years…

Sonic hedgehog promotes neurite outgrowth of cortical neurons under oxidative stress: Involving of mitochondria and energy metabolism.

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He, Weiliang; Cui, Lili; Zhang, Cong; Zhang, Xiangjian; He, Junna; Xie, Yanzhao; Chen, Yanxia

2017-01-01

Oxidative stress has been demonstrated to be involved in the etiology of several neurobiological disorders. Sonic hedgehog (Shh), a secreted glycoprotein factor, has been implicated in promoting several aspects of brain remodeling process. Mitochondria may play an important role in controlling fundamental processes in neuroplasticity. However, little evidence is available about the effect and the potential mechanism of Shh on neurite outgrowth in primary cortical neurons under oxidative stress. Here, we revealed that Shh treatment significantly increased the viability of cortical neurons in a dose-dependent manner, which was damaged by hydrogen peroxide (H 2 O 2 ). Shh alleviated the apoptosis rate of H 2 O 2 -induced neurons. Shh also increased neuritogenesis injuried by H 2 O 2 in primary cortical neurons. Moreover, Shh reduced the generation of reactive oxygen species (ROS), increased the activities of SOD and and decreased the productions of MDA. In addition, Shh protected mitochondrial functions, elevated the cellular ATP levels and amelioratesd the impairment of mitochondrial complex II activities of cortical neurons induced by H 2 O 2 . In conclusion, all these results suggest that Shh acts as a prosurvival factor playing an essential role to neurite outgrowth of cortical neuron under H 2 O 2 -induced oxidative stress, possibly through counteracting ROS release and preventing mitochondrial dysfunction and ATP as well as mitochondrial complex II activities against oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

Discrete β-adrenergic mechanisms regulate early and late erythropoiesis in erythropoietin-resistant anemia.

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Hasan, Shirin; Mosier, Michael J; Szilagyi, Andrea; Gamelli, Richard L; Muthumalaiappan, Kuzhali

2017-10-01

Anemia of critical illness is resistant to exogenous erythropoietin. Packed red blood cells transfusions is the only treatment option, and despite related cost and morbidity, there is a need for alternate strategies. Erythrocyte development can be divided into erythropoietin-dependent and erythropoietin-independent stages. We have shown previously that erythropoietin-dependent development is intact in burn patients and the erythropoietin-independent early commitment stage, which is regulated by β1/β2-adrenergic mechanisms, is compromised. Utilizing the scald burn injury model, we studied erythropoietin-independent late maturation stages and the effect of β1/β2, β-2, or β-3 blockade in burn mediated erythropoietin-resistant anemia. Burn mice were randomized to receive daily injections of propranolol (nonselective β1/β2 antagonist), nadolol (long-acting β1/β2 antagonist), butoxamine (selective β2 antagonist), or SR59230A (selective β3 antagonist) for 6 days after burn. Total bone marrow cells were characterized as nonerythroid cells, early and late erythroblasts, nucleated orthochromatic erythroblasts and enucleated reticulocyte subsets using CD71, Ter119, and Syto-16 by flow cytometry. Multipotential progenitors were probed for MafB expressing cells. Although propranolol improved early and late erythroblasts, only butoxamine and selective β3-antagonist administrations were positively reflected in the peripheral blood hemoglobin and red blood cells count. While burn impeded early commitment and late maturation stages, β1/β2 antagonism increased the early erythroblasts through commitment stages via β2 specific MafB regulation. β3 antagonism was more effective in improving overall red blood cells through late maturation stages. The study unfolds novel β2 and β3 adrenergic mechanisms orchestrating erythropoietin resistant anemia after burn, which impedes both the early commitment stage and the late maturation stages, respectively. Copyright © 2017

Proteomic analysis of differentiating neuroblastoma cells treated with sub-lethal neurite inhibitory concentrations of diazinon: Identification of novel biomarkers of effect

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Harris, W.; Sachana, M.; Flaskos, J.; Hargreaves, A.J.

2009-01-01

In previous work we showed that sub-lethal levels of diazinon inhibited neurite outgrowth in differentiating N2a neuroblastoma cells. Western blotting analysis targeted at proteins involved in axon growth and stress responses, revealed that such exposure led to a reduction in the levels of neurofilament heavy chain, microtubule associated protein 1 B (MAP 1B) and HSP-70. The aim of this study was to apply the approach of 2 dimensional polyacrylamide gel electrophoresis and mass spectrometry to identify novel biomarkers of effect. A number of proteins were found to be up-regulated compared to the control on silver-stained gels. These were classified in to 3 main groups of proteins: cytosolic factors, chaperones and the actin-binding protein cofilin, all of which are involved in cell differentiation, survival or metabolism. The changes observed for cofilin were further confirmed by quantitative Western blotting analysis with anti-actin and anti-cofilin antibodies. Indirect immunofluorescence staining with the same antibodies indicated that the microfilament network was disrupted in diazinon-treated cells. Our data suggest that microfilament organisation is disrupted by diazinon exposure, which may be related to increased cofilin expression.

Associations between Early Family Risk, Children's Behavioral Regulation, and Academic Achievement in Portugal

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Cadima, Joana; Gamelas, Ana M.; McClelland, Megan; Peixoto, Carla

2015-01-01

Research Findings: This study examined concurrent associations between family sociodemographic risk, self-regulation, and early literacy and mathematics in young children from Azores, Portugal (N = 186). Family sociodemographic risk was indexed by low maternal education, low family income, and low occupational status. Behavioral aspects of…

Early Childhood Profiles of Sleep Problems and Self-Regulation Predict Later School Adjustment

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Williams, Kate E.; Nicholson, Jan M.; Walker, Sue; Berthelsen, Donna

2016-01-01

Background: Children's sleep problems and self-regulation problems have been independently associated with poorer adjustment to school, but there has been limited exploration of longitudinal early childhood profiles that include both indicators. Aims: This study explores the normative developmental pathway for sleep problems and self-regulation…

GCN5 Regulates FGF Signaling and Activates Selective MYC Target Genes during Early Embryoid Body Differentiation

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Li Wang

2018-01-01

Full Text Available Precise control of gene expression during development is orchestrated by transcription factors and co-regulators including chromatin modifiers. How particular chromatin-modifying enzymes affect specific developmental processes is not well defined. Here, we report that GCN5, a histone acetyltransferase essential for embryonic development, is required for proper expression of multiple genes encoding components of the fibroblast growth factor (FGF signaling pathway in early embryoid bodies (EBs. Gcn5−/− EBs display deficient activation of ERK and p38, mislocalization of cytoskeletal components, and compromised capacity to differentiate toward mesodermal lineage. Genomic analyses identified seven genes as putative direct targets of GCN5 during early differentiation, four of which are cMYC targets. These findings established a link between GCN5 and the FGF signaling pathway and highlighted specific GCN5-MYC partnerships in gene regulation during early differentiation.

Children's Self-Regulation in the Context of Participatory Pedagogy in Early Childhood Education

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Kangas, Jonna; Ojala, Mikko; Venninen, Tuulikki

2015-01-01

Research Findings: Research has shown that self-regulation can support child development in the areas of children's attentional flexibility, working memory, and inhibitory control for excluding impulsive responses. How this is actually related in everyday pedagogical early childhood education (ECE) activities has rarely been studied in detail. In…

Network-based characterization of the synaptic proteome reveals that removal of epigenetic regulator Prmt8 restricts proteins associated with synaptic maturation.

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Lee, Patrick Kia Ming; Goh, Wilson Wen Bin; Sng, Judy Chia Ghee

2017-02-01

The brain adapts to dynamic environmental conditions by altering its epigenetic state, thereby influencing neuronal transcriptional programs. An example of an epigenetic modification is protein methylation, catalyzed by protein arginine methyltransferases (PRMT). One member, Prmt8, is selectively expressed in the central nervous system during a crucial phase of early development, but little else is known regarding its function. We hypothesize Prmt8 plays a role in synaptic maturation during development. To evaluate this, we used a proteome-wide approach to characterize the synaptic proteome of Prmt8 knockout versus wild-type mice. Through comparative network-based analyses, proteins and functional clusters related to neurite development were identified to be differentially regulated between the two genotypes. One interesting protein that was differentially regulated was tenascin-R (TNR). Chromatin immunoprecipitation demonstrated binding of PRMT8 to the tenascin-r (Tnr) promoter. TNR, a component of perineuronal nets, preserves structural integrity of synaptic connections within neuronal networks during the development of visual-somatosensory cortices. On closer inspection, Prmt8 removal increased net formation and decreased inhibitory parvalbumin-positive (PV+) puncta on pyramidal neurons, thereby hindering the maturation of circuits. Consequently, visual acuity of the knockout mice was reduced. Our results demonstrated Prmt8's involvement in synaptic maturation and its prospect as an epigenetic modulator of developmental neuroplasticity by regulating structural elements such as the perineuronal nets. © 2016 International Society for Neurochemistry.

The metabolic enhancer piracetam ameliorates the impairment of mitochondrial function and neurite outgrowth induced by beta-amyloid peptide.

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Kurz, C; Ungerer, I; Lipka, U; Kirr, S; Schütt, T; Eckert, A; Leuner, K; Müller, W E

2010-05-01

beta-Amyloid peptide (Abeta) is implicated in the pathogenesis of Alzheimer's disease by initiating a cascade of events from mitochondrial dysfunction to neuronal death. The metabolic enhancer piracetam has been shown to improve mitochondrial dysfunction following brain aging and experimentally induced oxidative stress. We used cell lines (PC12 and HEK cells) and murine dissociated brain cells. The protective effects of piracetam in vitro and ex vivo on Abeta-induced impairment of mitochondrial function (as mitochondrial membrane potential and ATP production), on secretion of soluble Abeta and on neurite outgrowth in PC12 cells were investigated. Piracetam improves mitochondrial function of PC12 cells and acutely dissociated brain cells from young NMRI mice following exposure to extracellular Abeta(1-42). Similar protective effects against Abeta(1-42) were observed in dissociated brain cells from aged NMRI mice, or mice transgenic for mutant human amyloid precursor protein (APP) treated with piracetam for 14 days. Soluble Abeta load was markedly diminished in the brain of those animals after treatment with piracetam. Abeta production by HEK cells stably transfected with mutant human APP was elevated by oxidative stress and this was reduced by piracetam. Impairment of neuritogenesis is an important consequence of Abeta-induced mitochondrial dysfunction and Abeta-induced reduction of neurite growth in PC12 cells was substantially improved by piracetam. Our findings strongly support the concept of improving mitochondrial function as an approach to ameliorate the detrimental effects of Abeta on brain function.

Early Postnatal Manganese Exposure Causes Lasting Impairment of Selective and Focused Attention and Arousal Regulation in Adult Rats

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Beaudin, Stephane A.; Strupp, Barbara J.; Strawderman, Myla; Smith, Donald R.

2016-01-01

Background: Studies in children and adolescents have associated early developmental manganese (Mn) exposure with inattention, impulsivity, hyperactivity, and oppositional behaviors, but causal inferences are precluded by the correlational nature of the data and generally limited control for potential confounders. Objectives: To determine whether early postnatal oral Mn exposure causes lasting attentional and impulse control deficits in adulthood, and whether continued lifelong Mn exposure exacerbates these effects, using a rat model of environmental Mn exposure. Methods: Neonates were exposed orally to 0, 25 or 50 mg Mn/kg/day during early postnatal life (PND 1–21) or throughout life from PND 1 until the end of the study. In adulthood, the animals were tested on a series of learning and attention tasks using the five-choice serial reaction time task. Results: Early postnatal Mn exposure caused lasting attentional dysfunction due to impairments in attentional preparedness, selective attention, and arousal regulation, whereas associative ability (learning) and impulse control were spared. The presence and severity of these deficits varied with the dose and duration of Mn exposure. Conclusions: This study is the first to show that developmental Mn exposure can cause lasting impairments in focused and selective attention and arousal regulation, and to identify the specific nature of the impairments. Given the importance of attention and arousal regulation in cognitive functioning, these findings substantiate concerns about the adverse effects of developmental Mn exposure in humans. Citation: Beaudin SA, Strupp BJ, Strawderman M, Smith DR. 2017. Early postnatal manganese exposure causes lasting impairment of selective and focused attention and arousal regulation in adult rats. Environ Health Perspect 125:230–237; http://dx.doi.org/10.1289/EHP258 PMID:27384154

Early Postnatal Manganese Exposure Causes Lasting Impairment of Selective and Focused Attention and Arousal Regulation in Adult Rats.

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Beaudin, Stephane A; Strupp, Barbara J; Strawderman, Myla; Smith, Donald R

2017-02-01

Studies in children and adolescents have associated early developmental manganese (Mn) exposure with inattention, impulsivity, hyperactivity, and oppositional behaviors, but causal inferences are precluded by the correlational nature of the data and generally limited control for potential confounders. To determine whether early postnatal oral Mn exposure causes lasting attentional and impulse control deficits in adulthood, and whether continued lifelong Mn exposure exacerbates these effects, using a rat model of environmental Mn exposure. Neonates were exposed orally to 0, 25 or 50 mg Mn/kg/day during early postnatal life (PND 1-21) or throughout life from PND 1 until the end of the study. In adulthood, the animals were tested on a series of learning and attention tasks using the five-choice serial reaction time task. Early postnatal Mn exposure caused lasting attentional dysfunction due to impairments in attentional preparedness, selective attention, and arousal regulation, whereas associative ability (learning) and impulse control were spared. The presence and severity of these deficits varied with the dose and duration of Mn exposure. This study is the first to show that developmental Mn exposure can cause lasting impairments in focused and selective attention and arousal regulation, and to identify the specific nature of the impairments. Given the importance of attention and arousal regulation in cognitive functioning, these findings substantiate concerns about the adverse effects of developmental Mn exposure in humans. Citation: Beaudin SA, Strupp BJ, Strawderman M, Smith DR. 2017. Early postnatal manganese exposure causes lasting impairment of selective and focused attention and arousal regulation in adult rats. Environ Health Perspect 125:230-237; http://dx.doi.org/10.1289/EHP258.

MiR-193b regulates early chondrogenesis by inhibiting the TGF-beta2 signaling pathway.

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Hou, Changhe; Yang, Zibo; Kang, Yan; Zhang, Ziji; Fu, Ming; He, Aishan; Zhang, Zhiqi; Liao, Weiming

2015-04-13

Cartilage generation and degradation are regulated by miRNAs. Our previous study has shown altered expression of miR-193b in chondrogenic human adipose-derived mesenchymal stem cells (hADSCs). In the current study, we investigated the role of miR-193b in chondrogenesis and cartilage degradation. Luciferase reporter assays showed that miR-193b targeted seed sequences of the TGFB2 and TGFBR3 3'-UTRs. MiR-193b suppressed the expression of early chondrogenic markers in chondrogenic ATDC5 cells, and TNF-alpha expression in IL-1b-induced PMCs. In conclusion, MiR-193b may inhibit early chondrogenesis by targeting TGFB2 and TGFBR3, and may regulate inflammation by repressing TNF-alpha expression in inflamed chondrocytes. Copyright © 2015. Published by Elsevier B.V.

The selective and inducible activation of endogenous PI 3-kinase in PC12 cells results in efficient NGF-mediated survival but defective neurite outgrowth.

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Ashcroft, M; Stephens, R M; Hallberg, B; Downward, J; Kaplan, D R

1999-08-12

The Trk/Nerve Growth Factor receptor mediates the rapid activation of a number of intracellular signaling proteins, including phosphatidylinositol 3-kinase (PI 3-kinase). Here, we describe a novel, NGF-inducible system that we used to specifically address the signaling potential of endogenous PI 3-kinase in NGF-mediated neuronal survival and differentiation processes. This system utilizes a Trk receptor mutant (Trk(def)) lacking sequences Y490, Y785 and KFG important for the activation of the major Trk targets; SHC, PLC-gammal, Ras, PI 3-kinase and SNT. Trk(def) was kinase active but defective for NGF-induced responses when stably expressed in PC12nnr5 cells (which lack detectable levels of TrkA and are non-responsive to NGF). The PI 3-kinase consensus binding site, YxxM (YVPM), was introduced into the insert region within the kinase domain of Trk(def). NGF-stimulated tyrosine phosphorylation of the Trk(def)+PI 3-kinase addback receptor, resulted in the direct association and selective activation of PI 3-kinase in vitro and the production of PI(3,4)P2 and PI(3,4,5)P3 in vivo (comparable to wild-type). PC12nnr5 cells stably expressing Trk(def) + PI 3-kinase, initiated neurite outgrowth but failed to stably extend and maintain these neurites in response to NGF as compared to PC12 parental cells, or PC12nnr5 cells overexpressing wild-type Trk. However, Trk(def) + PI 3-kinase was fully competent in mediating NGF-induced survival processes. We propose that while endogenous PI 3-kinase can contribute in part to neurite initiation processes, its selective activation and subsequent signaling to downstream effectors such as Akt, functions mainly to promote cell survival in the PC12 system.

Investing in the Early Childhood Mental Health Workforce Development: Enhancing Professionals' Competencies to Support Emotion and Behavior Regulation in Young Children.

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Ritblatt, Shulamit N; Hokoda, Audrey; Van Liew, Charles

2017-09-19

This paper delineates a preventive approach to early childhood mental health by preparing the workforce to provide relational, sensitive care to young children ages 0-5. One of the most prevalent issues in early childhood is behavioral challenges and the inability of young children to regulate themselves. This leads to an expulsion rate in early childhood (3-4 times higher than K-12 expulsion rate) and future mental health issues. The Early Childhood Social-Emotional and Behavior Regulation Intervention Specialist (EC-SEBRIS) graduate level certificate program was created to strengthen early care and education providers with the knowledge and practice of how to support emotion and behavior regulation in young children in their groups. Evaluation data provide evidence that early care and education professionals increased in their perception of self-efficacy and in their sensitivity of care and skills to support behavioral health in young children. Results indicated that the children in their care showed less challenging behaviors and increased social competencies. This manuscript highlights the importance of prevention and the dire need to provide young children with high-quality, appropriate care to support their mental health.

Conditioned medium of dental pulp cells stimulated by Chinese propolis show neuroprotection and neurite extension in vitro.

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Kudo, Daichi; Inden, Masatoshi; Sekine, Shin-Ichiro; Tamaoki, Naritaka; Iida, Kazuki; Naito, Eiji; Watanabe, Kazuhiro; Kamishina, Hiroaki; Shibata, Toshiyuki; Hozumi, Isao

2015-03-04

The purpose of this study was to clarify the effect of Chinese propolis on the expression level of neurotrophic factors in dental pulp cells (DPCs). We also investigated that the effects of the conditioned medium (CM) of DPCs stimulated by the propolis against oxidative and endoplasmic reticulum (ER) stresses in human neuroblastoma SH-SY5Y cells, and on neurite extensions in rat adrenal pheochromocytoma PC12 cells. To investigate the effect of the propolis on the levels of neurotrophic factors in DPCs, we performed a qRT-PCR experiment. As results, NGF, but not BDNF and NT-3, in DPCs was significantly elevated by the propolis in a concentration-dependent manner. H2O2-induced cell death was significantly inhibited by the treatment with the CM of DPCs. In addition, the treatment with the propolis-stimulated CM of DPCs had a more protective effect than that with the CM of DPCs. We also examine the effect of the propolis-stimulated CM of DPCs against a tunicamycin-induced ER stress. The treatment with the propolis-stimulated CM as well as the CM of DPCs significantly inhibited tunicamycin-induced cell death. Moreover, the treatment with the propolis-stimulated CM of DPCs significantly induced neurite outgrowth from PC12 cells than that with the CM of DPCs. These results suggest that the CM of DPCs as well as DPCs will be an efficient source of new treatments for neurodegenerative diseases and that the propolis promote the advantage of the CM of DPCs via producing neurotrophic factors. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

MicroRNA-4639 Is a Regulator of DJ-1 Expression and a Potential Early Diagnostic Marker for Parkinson’s Disease

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Yimeng Chen

2017-07-01

Full Text Available Parkinson’s disease (PD is the second most common neurodegenerative disorder and has profound impacts on the daily lives of patients. However, there is a lack of effective biomarkers for early diagnosis, and the mechanisms of PD pathogenesis remain obscure. microRNAs (miRNAs are post-transcriptional gene regulators and can be easily detected in plasma, which suggests a promising role as diagnostic markers. Here, we aimed to explore a peripheral biomarker, which not only can be applied for early diagnosis of PD but also has the potential to be a therapeutic target. Through miRNA microarray screening and further validation in plasma from 169 sporadic PD patients, 170 healthy controls, and 60 essential tremor (ET patients, hsa-miR-4639-5p level was identified to be significantly up-regulated in PD patients. Also, it was able to discriminate between early PD patients (disease duration ≤2 years or Hoehn and Yahr stage 1–2.5 and healthy controls. Furthermore, hsa-miR-4639-5p was shown to negatively regulate DJ-1 (PARK7, a well-known PD-related gene, in the post-transcriptional level. Abnormal up-regulation of hsa-miR-4639-5p caused down-regulation of DJ-1 protein level, leading to severe oxidative stress and neuronal death. In conclusion, hsa-miR-4639-5p has the potential to be a peripheral diagnostic biomarker and therapeutic target for early PD.

Evolution of allosteric regulation in chorismate mutases from early plants

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Kroll, Kourtney; Holland, Cynthia K.; Starks, Courtney M.; Jez, Joseph M.

2017-09-28

Plants, fungi, and bacteria synthesize the aromatic amino acids: l-phenylalanine, l-tyrosine, and l-tryptophan. Chorismate mutase catalyzes the branch point reaction of phenylalanine and tyrosine biosynthesis to generate prephenate. In Arabidopsis thaliana, there are two plastid-localized chorismate mutases that are allosterically regulated (AtCM1 and AtCM3) and one cytosolic isoform (AtCM2) that is unregulated. Previous analysis of plant chorismate mutases suggested that the enzymes from early plants (i.e. bryophytes/moss, lycophytes, and basal angiosperms) formed a clade distinct from the isoforms found in flowering plants; however, no biochemical information on these enzymes is available. To understand the evolution of allosteric regulation in plant chorismate mutases, we analyzed a basal lineage of plant enzymes homologous to AtCM1 based on sequence similarity. The chorismate mutases from the moss/bryophyte Physcomitrella patens (PpCM1 and PpCM2), the lycophyte Selaginella moellendorffii (SmCM), and the basal angiosperm Amborella trichopoda (AmtCM1 and AmtCM2) were characterized biochemically. Tryptophan was a positive effector for each of the five enzymes examined. Histidine was a weak positive effector for PpCM1 and AmtCM1. Neither tyrosine nor phenylalanine altered the activity of SmCM; however, tyrosine was a negative regulator of the other four enzymes. Phenylalanine down-regulates both moss enzymes and AmtCM2. The 2.0 Å X-ray crystal structure of PpCM1 in complex with the tryptophan identified the allosteric effector site and reveals structural differences between the R- (more active) and T-state (less active) forms of plant chorismate mutases. Molecular insight into the basal plant chorismate mutases guides our understanding of the evolution of allosteric regulation in these enzymes.

The Traditional Japanese Herbal Medicine Hachimijiogan Elicits Neurite Outgrowth Effects in PC12 Cells and Improves Cognitive in AD Model Rats via Phosphorylation of CREB

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Kaori Kubota

2017-11-01

Full Text Available Hachimijiogan (HJG is a traditional herbal medicine that improves anxiety disorders in patients with dementia. In this study, we tested the hypothesis that HJG exerts neurotrophic factor-like effects to ameliorate memory impairment in Alzheimer disease (AD model rats. First, we describe that HJG acts to induce neurite outgrowth in PC12 cells (a rat pheochromocytoma cell line like nerve growth factor (NGF in a concentration-dependent manner (3 μg/ml HJG, p < 0.05; 10–500 μg/ml HJG, p < 0.001. While six herbal constituents of HJG, Rehmannia root, Dioscorea rhizome, Rhizoma Alismatis, Poria sclerotium, Moutan bark, and Cinnamon bark, could induce neurite outgrowth effects, the effect was strongest with HJG (500 μg/ml. Second, we demonstrated that HJG-induced neurite outgrowth was blocked by an inhibitor of cAMP response element binding protein (CREB, KG-501 (10 μM, p < 0.001. Moreover, HJG was observed to induce CREB phosphorylation 20–90 min after treatment (20 min, 2.50 ± 0.58-fold and CRE-mediated transcription in cultured PC12 cells (500 μg/ml, p < 0.01; 1000 μg/ml, p < 0.001. These results suggest a CREB-dependent mechanism underlies the neurotrophic effects of HJG. Finally, we examined improvements of memory impairment following HJG treatment using a Morris water maze in AD model animals (CI + Aβ rats. Repeated oral administration of HJG improved memory impairment (300 mg/kg, p < 0.05; 1000 mg/kg, p < 0.001 and induced CREB phosphorylation within the hippocampus (1000 mg/kg, p < 0.01. Together, our results suggest that HJG possesses neurotrophic effects similar to those of NGF, and can ameliorate cognitive dysfunction in a rat dementia model via CREB activation. Thus, HJG could potentially be a substitute for neurotrophic factors as a treatment for dementia.

Distribution of Endogenous NO Regulates Early Gravitropic Response and PIN2 Localization in Arabidopsis Roots

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Ramiro París

2018-04-01

Full Text Available High-resolution and automated image analysis of individual roots demonstrated that endogenous nitric oxide (NO contribute significantly to gravitropism of Arabidopsis roots. Lowering of endogenous NO concentrations strongly reduced and even reversed gravitropism, resulting in upward bending, without affecting root growth rate. Notably, the asymmetric accumulation of NO along the upper and lower sides of roots correlated with a positive gravitropic response. Detection of NO by the specific DAF-FM DA fluorescent probe revealed that NO was higher at the lower side of horizontally-oriented roots returning to initial values 2 h after the onset of gravistimulation. We demonstrate that NO promotes plasma membrane re-localization of PIN2 in epidermal cells, which is required during the early root gravitropic response. The dynamic and asymmetric localization of both auxin and NO is critical to regulate auxin polar transport during gravitropism. Our results collectively suggest that, although auxin and NO crosstalk occurs at different levels of regulation, they converge in the regulation of PIN2 membrane trafficking in gravistimulated roots, supporting the notion that a temporally and spatially coordinated network of signal molecules could participate in the early phases of auxin polar transport during gravitropism.

Toward the Development of an Artificial Brain on a Micropatterned and Material-Regulated Biochip by Guiding and Promoting the Differentiation and Neurite Outgrowth of Neural Stem/Progenitor Cells.

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Liu, Yung-Chiang; Lee, I-Chi; Lei, Kin Fong

2018-02-14

An in vitro model mimicking the in vivo environment of the brain must be developed to study neural communication and regeneration and to obtain an understanding of cellular and molecular responses. In this work, a multilayered neural network was successfully constructed on a biochip by guiding and promoting neural stem/progenitor cell differentiation and network formation. The biochip consisted of 3 × 3 arrays of cultured wells connected with channels. Neurospheroids were cultured on polyelectrolyte multilayer (PEM) films in the culture wells. Neurite outgrowth and neural differentiation were guided and promoted by the micropatterns and the PEM films. After 5 days in culture, a 3 × 3 neural network was constructed on the biochip. The function and the connections of the network were evaluated by immunocytochemistry and impedance measurements. Neurons were generated and produced functional and recyclable synaptic vesicles. Moreover, the electrical connections of the neural network were confirmed by measuring the impedance across the neurospheroids. The current work facilitates the development of an artificial brain on a chip for investigations of electrical stimulations and recordings of multilayered neural communication and regeneration.

Emotional Reactivity and Regulation in Infancy Interact to Predict Executive Functioning in Early Childhood

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Ursache, Alexandra; Blair, Clancy; Stifter, Cynthia; Voegtline, Kristin

2013-01-01

The relation of observed emotional reactivity and regulation in infancy to executive function in early childhood was examined in a prospective longitudinal sample of 1,292 children from predominantly low-income and rural communities. Children participated in a fear eliciting task at ages 7, 15, and 24 months and completed an executive function…

Linking Self-Regulation and Risk Proneness to Risky Sexual Behavior: Pathways through Peer Pressure and Early Substance Use

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Crockett, Lisa J.; Raffaelli, Marcela; Shen, Yuh-Ling

2006-01-01

The linkages between self-regulation in childhood, risk proneness in early adolescence, and risky sexual behavior in mid-adolescence were examined in a cohort of children (N=518) from the National Longitudinal Survey of Youth. The possible mediating role of two early adolescent variables (substance use and negative peer pressure) was also…

First-in-Man Intrathecal Application of Neurite Growth-Promoting Anti-Nogo-A Antibodies in Acute Spinal Cord Injury.

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Kucher, Klaus; Johns, Donald; Maier, Doris; Abel, Rainer; Badke, Andreas; Baron, Hagen; Thietje, Roland; Casha, Steven; Meindl, Renate; Gomez-Mancilla, Baltazar; Pfister, Christian; Rupp, Rüdiger; Weidner, Norbert; Mir, Anis; Schwab, Martin E; Curt, Armin

2018-05-01

Neutralization of central nervous system neurite growth inhibitory factors, for example, Nogo-A, is a promising approach to improving recovery following spinal cord injury (SCI). In animal SCI models, intrathecal delivery of anti-Nogo-A antibodies promoted regenerative neurite growth and functional recovery. This first-in-man study assessed the feasibility, safety, tolerability, pharmacokinetics, and preliminary efficacy of the human anti-Nogo-A antibody ATI355 following intrathecal administration in patients with acute, complete traumatic paraplegia and tetraplegia. Patients (N = 52) started treatment 4 to 60 days postinjury. Four consecutive dose-escalation cohorts received 5 to 30 mg/2.5 mL/day continuous intrathecal ATI355 infusion over 24 hours to 28 days. Following pharmacokinetic evaluation, 2 further cohorts received a bolus regimen (6 intrathecal injections of 22.5 and 45 mg/3 mL, respectively, over 4 weeks). ATI355 was well tolerated up to 1-year follow-up. All patients experienced ≥1 adverse events (AEs). The 581 reported AEs were mostly mild and to be expected following acute SCI. Fifteen patients reported 16 serious AEs, none related to ATI355; one bacterial meningitis case was considered related to intrathecal administration. ATI355 serum levels showed dose-dependency, and intersubject cerebrospinal fluid levels were highly variable after infusion and bolus injection. In 1 paraplegic patient, motor scores improved by 8 points. In tetraplegic patients, mean total motor scores increased, with 3/19 gaining >10 points, and 1/19 27 points at Week 48. Conversion from complete to incomplete SCI occurred in 7/19 patients with tetraplegia. ATI335 was well tolerated in humans; efficacy trials using intrathecal antibody administration may be considered in acute SCI.

The gga-let-7 family post-transcriptionally regulates TGFBR1 and LIN28B during the differentiation process in early chick development.

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Lee, Sang In; Jeon, Mi-Hyang; Kim, Jeom Sun; Jeon, Ik-Soo; Byun, Sung June

2015-12-01

Early chick embryogenesis is governed by a complex mechanism involving transcriptional and post-transcriptional regulation, although how post-transcriptional processes influence the balance between pluripotency and differentiation during early chick development have not been previously investigated. Here, we characterized the microRNA (miRNA) signature associated with differentiation in the chick embryo, and found that as expression of the gga-let-7 family increases through early development, expression of their direct targets, TGFBR1 and LIN28B, decreases; indeed, gga-let-7a-5p and gga-let-7b miRNAs directly bind to TGFBR1 and LIN28B transcripts. Our data further indicate that TGFBR1 and LIN28B maintain pluripotency by regulating POUV, NANOG, and CRIPTO. Therefore, gga-let-7 miRNAs act as post-transcriptional regulators of differentiation in blastodermal cells by repressing the expression of the TGFBR1 and LIN28B, which intrinsically controls blastodermal cell differentiation in early chick development. © 2015 Wiley Periodicals, Inc.

Zebrafish foxo3b negatively regulates canonical Wnt signaling to affect early embryogenesis.

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Xun-wei Xie

Full Text Available FOXO genes are involved in many aspects of development and vascular homeostasis by regulating cell apoptosis, proliferation, and the control of oxidative stress. In addition, FOXO genes have been showed to inhibit Wnt/β-catenin signaling by competing with T cell factor to bind to β-catenin. However, how important of this inhibition in vivo, particularly in embryogenesis is still unknown. To demonstrate the roles of FOXO genes in embryogenesis will help us to further understand their relevant physiological functions. Zebrafish foxo3b gene, an orthologue of mammalian FOXO3, was expressed maternally and distributed ubiquitously during early embryogenesis and later restricted to brain. After morpholino-mediated knockdown of foxo3b, the zebrafish embryos exhibited defects in axis and neuroectoderm formation, suggesting its critical role in early embryogenesis. The embryo-developmental marker gene staining at different stages, phenotype analysis and rescue assays revealed that foxo3b acted its role through negatively regulating both maternal and zygotic Wnt/β-catenin signaling. Moreover, we found that foxo3b could interact with zebrafish β-catenin1 and β-catenin2 to suppress their transactivation in vitro and in vivo, further confirming its role relevant to the inhibition of Wnt/β-catenin signaling. Taken together, we revealed that foxo3b played a very important role in embryogenesis and negatively regulated maternal and zygotic Wnt/β-catenin signaling by directly interacting with both β-catenin1 and β-catenin2. Our studies provide an in vivo model for illustrating function of FOXO transcription factors in embryogenesis.

Downstream of tyrosine kinase/docking protein 6, as a novel substrate of tropomyosin-related kinase C receptor, is involved in neurotrophin 3-mediated neurite outgrowth in mouse cortex neurons

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Yuan Jian

2010-06-01

Full Text Available Abstract Background The downstream of tyrosine kinase/docking protein (Dok adaptor protein family has seven members, Dok1 to Dok7, that act as substrates of multiple receptor tyrosine kinase and non-receptor tyrosine kinase. The tropomyosin-related kinase (Trk receptor family, which has three members (TrkA, TrkB and TrkC, are receptor tyrosine kinases that play pivotal roles in many stages of nervous system development, such as differentiation, migration, axon and dendrite projection and neuron patterning. Upon related neurotrophin growth factor stimulation, dimerisation and autophosphorylation of Trk receptors can occur, recruiting adaptor proteins to mediate signal transduction. Results In this report, by using yeast two-hybrid assays, glutathione S-transferase (GST precipitation assays and coimmunoprecipitation (Co-IP experiments, we demonstrate that Dok6 selectively binds to the NPQY motif of TrkC through its phosphotyrosine-binding (PTB domain in a kinase activity-dependent manner. We further confirmed their interaction by coimmunoprecipitation and colocalisation in E18.5 mouse cortex neurons, which provided more in vivo evidence. Next, we demonstrated that Dok6 is involved in neurite outgrowth in mouse cortex neurons via the RNAi method. Knockdown of Dok6 decreased neurite outgrowth in cortical neurons upon neurotrophin 3 (NT-3 stimulation. Conclusions We conclude that Dok6 interacts with the NPQY motif of the TrkC receptor through its PTB domain in a kinase activity-dependent manner, and works as a novel substrate of the TrkC receptor involved in NT-3-mediated neurite outgrowth in mouse cortex neurons.

Atrial natriuretic peptide regulates Ca channel in early developmental cardiomyocytes.

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Lin Miao

Full Text Available BACKGROUND: Cardiomyocytes derived from murine embryonic stem (ES cells possess various membrane currents and signaling cascades link to that of embryonic hearts. The role of atrial natriuretic peptide (ANP in regulation of membrane potentials and Ca(2+ currents has not been investigated in developmental cardiomyocytes. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the role of ANP in regulating L-type Ca(2+ channel current (I(CaL in different developmental stages of cardiomyocytes derived from ES cells. ANP decreased the frequency of action potentials (APs in early developmental stage (EDS cardiomyocytes, embryonic bodies (EB as well as whole embryo hearts. ANP exerted an inhibitory effect on basal I(CaL in about 70% EDS cardiomyocytes tested but only in about 30% late developmental stage (LDS cells. However, after stimulation of I(CaL by isoproterenol (ISO in LDS cells, ANP inhibited the response in about 70% cells. The depression of I(CaL induced by ANP was not affected by either Nomega, Nitro-L-Arginine methyl ester (L-NAME, a nitric oxide synthetase (NOS inhibitor, or KT5823, a cGMP-dependent protein kinase (PKG selective inhibitor, in either EDS and LDS cells; whereas depression of I(CaL by ANP was entirely abolished by erythro-9-(2-Hydroxy-3-nonyl adenine (EHNA, a selective inhibitor of type 2 phosphodiesterase(PDE2 in most cells tested. CONCLUSION/SIGNIFICANCES: Taken together, these results indicate that ANP induced depression of action potentials and I(CaL is due to activation of particulate guanylyl cyclase (GC, cGMP production and cGMP-activation of PDE2 mediated depression of adenosine 3', 5'-cyclic monophophate (cAMP-cAMP-dependent protein kinase (PKA in early cardiomyogenesis.

Critical time window of neuronal cholesterol synthesis during neurite outgrowth.

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Fünfschilling, Ursula; Jockusch, Wolf J; Sivakumar, Nandhini; Möbius, Wiebke; Corthals, Kristina; Li, Sai; Quintes, Susanne; Kim, Younghoon; Schaap, Iwan A T; Rhee, Jeong-Seop; Nave, Klaus-Armin; Saher, Gesine

2012-05-30

Cholesterol is an essential membrane component enriched in plasma membranes, growth cones, and synapses. The brain normally synthesizes all cholesterol locally, but the contribution of individual cell types to brain cholesterol metabolism is unknown. To investigate whether cortical projection neurons in vivo essentially require cholesterol biosynthesis and which cell types support neurons, we have conditionally ablated the cholesterol biosynthesis in these neurons in mice either embryonically or postnatally. We found that cortical projection neurons synthesize cholesterol during their entire lifetime. At all stages, they can also benefit from glial support. Adult neurons that lack cholesterol biosynthesis are mainly supported by astrocytes such that their functional integrity is preserved. In contrast, microglial cells support young neurons. However, compensatory efforts of microglia are only transient leading to layer-specific neuronal death and the reduction of cortical projections. Hence, during the phase of maximal membrane growth and maximal cholesterol demand, neuronal cholesterol biosynthesis is indispensable. Analysis of primary neurons revealed that neurons tolerate only slight alteration in the cholesterol content and plasma membrane tension. This quality control allows neurons to differentiate normally and adjusts the extent of neurite outgrowth, the number of functional growth cones and synapses to the available cholesterol. This study highlights both the flexibility and the limits of horizontal cholesterol transfer in vivo and may have implications for the understanding of neurodegenerative diseases.

Antiangiogenic Treatment Diminishes Renal Injury and Dysfunction via Regulation of Local AKT in Early Experimental Diabetes

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Bai, Xiaoyan; Li, Xiao; Tian, Jianwei; Zhou, Zhanmei

2014-01-01

In view of increased vascular endothelial growth factor-A (VEGF-A) expression and renal dysfunction in early diabetes, we designed a study to test whether VEGF-A inhibition can prevent early renal injury and dysfunction. We investigated the relationship and mechanism between VEGF-A and AKT regulation. In vitro, VEGF-A small interfering RNA (siRNA) and AKT inhibitor MK-2206 were employed to podocytes and NRK-52 cells cultured in high glucose (30 mM). In vivo, the antiangiogenic drug endostatin...

Early Seizure Detection Based on Cardiac Autonomic Regulation Dynamics

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Jonatas Pavei

2017-10-01

Full Text Available Epilepsy is a neurological disorder that causes changes in the autonomic nervous system. Heart rate variability (HRV reflects the regulation of cardiac activity and autonomic nervous system tone. The early detection of epileptic seizures could foster the use of new treatment approaches. This study presents a new methodology for the prediction of epileptic seizures using HRV signals. Eigendecomposition of HRV parameter covariance matrices was used to create an input for a support vector machine (SVM-based classifier. We analyzed clinical data from 12 patients (9 female; 3 male; age 34.5 ± 7.5 years, involving 34 seizures and a total of 55.2 h of interictal electrocardiogram (ECG recordings. Data from 123.6 h of ECG recordings from healthy subjects were used to test false positive rate per hour (FP/h in a completely independent data set. Our methodological approach allowed the detection of impending seizures from 5 min to just before the onset of a clinical/electrical seizure with a sensitivity of 94.1%. The FP rate was 0.49 h−1 in the recordings from patients with epilepsy and 0.19 h−1 in the recordings from healthy subjects. Our results suggest that it is feasible to use the dynamics of HRV parameters for the early detection and, potentially, the prediction of epileptic seizures.

Reverse-engineering of gene networks for regulating early blood development from single-cell measurements.

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Wei, Jiangyong; Hu, Xiaohua; Zou, Xiufen; Tian, Tianhai

2017-12-28

Recent advances in omics technologies have raised great opportunities to study large-scale regulatory networks inside the cell. In addition, single-cell experiments have measured the gene and protein activities in a large number of cells under the same experimental conditions. However, a significant challenge in computational biology and bioinformatics is how to derive quantitative information from the single-cell observations and how to develop sophisticated mathematical models to describe the dynamic properties of regulatory networks using the derived quantitative information. This work designs an integrated approach to reverse-engineer gene networks for regulating early blood development based on singel-cell experimental observations. The wanderlust algorithm is initially used to develop the pseudo-trajectory for the activities of a number of genes. Since the gene expression data in the developed pseudo-trajectory show large fluctuations, we then use Gaussian process regression methods to smooth the gene express data in order to obtain pseudo-trajectories with much less fluctuations. The proposed integrated framework consists of both bioinformatics algorithms to reconstruct the regulatory network and mathematical models using differential equations to describe the dynamics of gene expression. The developed approach is applied to study the network regulating early blood cell development. A graphic model is constructed for a regulatory network with forty genes and a dynamic model using differential equations is developed for a network of nine genes. Numerical results suggests that the proposed model is able to match experimental data very well. We also examine the networks with more regulatory relations and numerical results show that more regulations may exist. We test the possibility of auto-regulation but numerical simulations do not support the positive auto-regulation. In addition, robustness is used as an importantly additional criterion to select candidate

Algal Toxin Azaspiracid-1 Induces Early Neuronal Differentiation and Alters Peripherin Isoform Stoichiometry

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Linda V. Hjørnevik

2015-12-01

Full Text Available Azaspiracid-1 is an algal toxin that accumulates in edible mussels, and ingestion may result in human illness as manifested by vomiting and diarrhoea. When injected into mice, it causes neurotoxicological symptoms and death. Although it is well known that azaspiracid-1 is toxic to most cells and cell lines, little is known about its biological target(s. A rat PC12 cell line, commonly used as a model for the peripheral nervous system, was used to study the neurotoxicological effects of azaspiracid-1. Azaspiracid-1 induced differentiation-related morphological changes followed by a latter cell death. The differentiated phenotype showed peripherin-labelled neurite-like processes simultaneously as a specific isoform of peripherin was down-regulated. The precise mechanism behind this down-regulation remains uncertain. However, this study provides new insights into the neurological effects of azaspiracid-1 and into the biological significance of specific isoforms of peripherin.

Regulation of Arabidopsis Early Anther Development by Putative Cell-Cell Signaling Molecules and Transcriptional Regulators

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Yu-Jin Sun; Carey LH Hord; Chang-Bin Chen; Hong Ma

2007-01-01

Anther development in flowering plants involves the formation of several cell types, including the tapetal and pollen mother cells. The use of genetic and molecular tools has led to the identification and characterization of genes that are critical for normal cell division and differentiation in Arabidopsis early anther development. We review here several recent studies on these genes, including the demonstration that the putative receptor protein kinases BAM1 and BAM2 together play essential roles in the control of early cell division and differentiation. In addition, we discuss the hypothesis that BAM1/2 may form a positive-negative feedback regulatory loop with a previously identified key regulator, SPOROCYTELESS (also called NOZZLE),to control the balance between sporogenous and somatic cell types in the anther. Furthermore, we summarize the isolation and functional analysis of the DYSFUNCTIONAL TAPETUM1 (DYT1) gene in promoting proper tapetal cell differentiation. Our finding that DYT1 encodes a putative transcription factor of the bHLH family, as well as relevant expression analyses, strongly supports a model that DYT1 serves as a critical link between upstream factors and downstream target genes that are critical for normal tapetum development and function. These studies, together with other recently published works, indicate that cell-cell communication and transcriptional control are key processes essential for cell fate specification in anther development.

Executive Function in Adolescence: Associations with Child and Family Risk Factors and Self-Regulation in Early Childhood.

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Berthelsen, Donna; Hayes, Nicole; White, Sonia L J; Williams, Kate E

2017-01-01

Executive functions are important higher-order cognitive skills for goal-directed thought and action. These capacities contribute to successful school achievement and lifelong wellbeing. The importance of executive functions to children's education begins in early childhood and continues throughout development. This study explores contributions of child and family factors in early childhood to the development of executive function in adolescence. Analyses draw on data from the nationally representative study, Growing up in Australia: The Longitudinal Study of Australian Children . Participants are 4819 children in the Kindergarten Cohort who were recruited at age 4-5 years. Path analyses were employed to examine contributions of early childhood factors, including family socio-economic position (SEP), parenting behaviors, maternal mental health, and a child behavioral risk index, to the development of executive function in adolescence. The influence of children's early self-regulatory behaviors (attentional regulation at 4-5 years and approaches to learning at 6-7 years) were also taken into account. A composite score for the outcome measure of executive function was constructed from scores on three Cogstate computerized tasks for assessing cognition and measured visual attention, visual working memory, and spatial problem-solving. Covariates included child gender, age at assessment of executive function, Aboriginal and Torres Strait Islander status, speaking a language other than English at home, and child's receptive vocabulary skills. There were significant indirect effects involving child and family risk factors measured at 4-5 years on executive function at age 14-15 years, mediated by measures of self-regulatory behavior. Child behavioral risk, family SEP and parenting behaviors (anger, warmth, and consistency) were associated with attentional regulation at 4-5 years which, in turn, was significantly associated with approaches to learning at 6-7 years. Both

TGF-β/Smad2/3 signaling directly regulates several miRNAs in mouse ES cells and early embryos.

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Nicholas Redshaw

Full Text Available The Transforming Growth Factor-β (TGF-β signaling pathway is one of the major pathways essential for normal embryonic development and tissue homeostasis, with anti-tumor but also pro-metastatic properties in cancer. This pathway directly regulates several target genes that mediate its downstream functions, however very few microRNAs (miRNAs have been identified as targets. miRNAs are modulators of gene expression with essential roles in development and a clear association with diseases including cancer. Little is known about the transcriptional regulation of the primary transcripts (pri-miRNA, pri-miR from which several mature miRNAs are often derived. Here we present the identification of miRNAs regulated by TGF-β signaling in mouse embryonic stem (ES cells and early embryos. We used an inducible ES cell system to maintain high levels of the TGF-β activated/phosphorylated Smad2/3 effectors, which are the transcription factors of the pathway, and a specific inhibitor that blocks their activation. By performing short RNA deep-sequencing after 12 hours Smad2/3 activation and after 16 hours inhibition, we generated a database of responsive miRNAs. Promoter/enhancer analysis of a subset of these miRNAs revealed that the transcription of pri-miR-181c/d and the pri-miR-341∼3072 cluster were found to depend on activated Smad2/3. Several of these miRNAs are expressed in early mouse embryos, when the pathway is known to play an essential role. Treatment of embryos with TGF-β inhibitor caused a reduction of their levels confirming that they are targets of this pathway in vivo. Furthermore, we showed that pri-miR-341∼3072 transcription also depends on FoxH1, a known Smad2/3 transcription partner during early development. Together, our data show that miRNAs are regulated directly by the TGF-β/Smad2/3 pathway in ES cells and early embryos. As somatic abnormalities in functions known to be regulated by the TGF-β/Smad2/3 pathway underlie tumor

Examining the Predictive Relations between Two Aspects of Self-Regulation and Growth in Preschool Children’s Early Literacy Skills

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Lonigan, Christopher J.; Allan, Darcey M.; Phillips, Beth M.

2016-01-01

There is strong evidence that self-regulatory processes are linked to early academic skills both concurrently and longitudinally. The majority of extant longitudinal studies, however, have been conducted using autoregressive techniques that may not accurately model change across time. The purpose of this study was to examine the unique associations between two components of self-regulation, attention and executive functioning (EF), and growth in early literacy skills over the preschool year using latent-growth-curve analysis. The sample included 1,082 preschool children (M-age = 55.0 months, SD = 3.73). Children completed measures of vocabulary, syntax, phonological awareness, print knowledge, cognitive ability, and self-regulation, and children’s classroom teachers completed a behavior rating measure. To examine the independent relations of the self-regulatory skills and cognitive ability with children’s initial early literacy skills and growth across the preschool year, growth models in which the intercept and slope were simultaneously regressed on each of the predictor variables were examined. Because of the significant relation between intercept and slope for most outcomes, slope was regressed on intercept in the models to allow a determination of direct and indirect effects of the predictors on growth in children’s language and literacy skills across the preschool year. In general, both teacher-rated inattention and directly measured EF were uniquely associated with initial skills level; however, only teacher-rated inattention uniquely predicted growth in early literacy skills. These findings suggest that teacher-ratings of inattention may measure an aspect of self-regulation that is particularly associated with the acquisition of academic skills in early childhood. PMID:27854463

The Secretome of Bone Marrow and Wharton Jelly Derived Mesenchymal Stem Cells Induces Differentiation and Neurite Outgrowth in SH-SY5Y Cells

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Ana O. Pires

2014-01-01

Full Text Available The goal of this study was to determine and compare the effects of the secretome of mesenchymal stem cells (MSCs isolated from human bone-marrow (BMSCs and the Wharton jelly surrounding the vein and arteries of the umbilical cord (human umbilical cord perivascular cells (HUCPVCs on the survival and differentiation of a human neuroblastoma cell line (SH-SY5Y. For this purpose, SH-SY5Y cells were differentiated with conditioned media (CM from the MSCs populations referred above. Retinoic acid cultured cells were used as control for neuronal differentiated SH-SY5Y cells. SH-SY5Y cells viability assessment revealed that the secretome of BMSCs and HUCPVCs, in the form of CM, was able to induce their survival. Moreover, immunocytochemical experiments showed that CM from both MSCs was capable of inducing neuronal differentiation of SH-SY5Y cells. Finally, neurite lengths assessment and quantitative real-time reverse-transcription polymerase chain reaction (RT-PCR analysis demonstrated that CM from BMSCs and HUCPVCs differently induced neurite outgrowth and mRNA levels of neuronal markers exhibited by SH-SY5Y cells. Overall, our results show that the secretome of both BMSCs and HUCPVCs was capable of supporting SH-SY5Y cells survival and promoting their differentiation towards a neuronal phenotype.

Regulation of the autophagy protein LC3 by phosphorylation

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Cherra, Salvatore J.; Kulich, Scott M.; Uechi, Guy; Balasubramani, Manimalha; Mountzouris, John; Day, Billy W.

2010-01-01

Macroautophagy is a major catabolic pathway that impacts cell survival, differentiation, tumorigenesis, and neurodegeneration. Although bulk degradation sustains carbon sources during starvation, autophagy contributes to shrinkage of differentiated neuronal processes. Identification of autophagy-related genes has spurred rapid advances in understanding the recruitment of microtubule-associated protein 1 light chain 3 (LC3) in autophagy induction, although braking mechanisms remain less understood. Using mass spectrometry, we identified a direct protein kinase A (PKA) phosphorylation site on LC3 that regulates its participation in autophagy. Both metabolic (rapamycin) and pathological (MPP+) inducers of autophagy caused dephosphorylation of endogenous LC3. The pseudophosphorylated LC3 mutant showed reduced recruitment to autophagosomes, whereas the nonphosphorylatable mutant exhibited enhanced puncta formation. Finally, autophagy-dependent neurite shortening induced by expression of a Parkinson disease–associated G2019S mutation in leucine-rich repeat kinase 2 was inhibited by dibutyryl–cyclic adenosine monophosphate, cytoplasmic expression of the PKA catalytic subunit, or the LC3 phosphorylation mimic. These data demonstrate a role for phosphorylation in regulating LC3 activity. PMID:20713600

Mosaic and Regulation Phenomena during the Early Formation of the Chick Blastoderm

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Marc Callebaut

2010-01-01

Full Text Available After culturing symmetrically hemisectioned unincubated chicken blastoderms, asymmetric hemiembryos developed (indicating mosaic development. In the present study, we observed that after prolonged culture, the further asymmetric development (way with no possible return becomes profoundly disturbed, more particularly the Rauber's sickle-dependent phenomena: gastrulation and the formation of the coelomo-cardiovascular complex with absence of heart and pericard development. By contrast, the neural plate develops symmetrically. Asymmetrical ablation of Rauber's sickle and the neighboring upper layer results in the development of an apparently normal symmetrical embryo. Indeed, at the unoperated side, a normal half coelomo-cardiovascular system develops with a unilateral or bilateral heart tube and pericard formation (indicating regulation. Both regulation and mosaicism indicate that during normal early development, the interaction between the left and right sides of the caudal area centralis of the blastoderm is indispensable, depending on the spatial relationship between the elementary tissues (upper layer, Rauber's sickle, endophyll.

O exame neurológico inicial na hanseníase multibacilar: correlação entre a presença de nervos afetados com incapacidades presentes no diagnóstico e com a ocorrência de neurites francas

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Pimentel Maria Inês Fernandes

2003-01-01

Full Text Available FUNDAMENTOS: As incapacidades constituem o principal problema decorrente da hanseníase. É importante identificar os fatores de risco envolvidos, de modo a acompanhar os pacientes mais propensos com maior atenção. OBJETIVOS: Determinar se a presença de nervos periféricos espessados e/ou dolorosos no momento do diagnóstico se correlaciona com a ocorrência de incapacidades físicas no exame inicial, bem como com episódios posteriores de neurite, em pacientes multibacilares, durante e após a poliquimioterapia. MÉTODOS: Foram estudados 103 pacientes portadores de formas multibacilares de hanseníase, sendo anotados a presença de nervos periféricos acometidos no momento o diagnóstico, o grau de incapacidade antes do tratamento (GIAT, e a ocorrência de episódios de neurites durante e após a poliquimioterapia para multibacilares. RESULTADOS: A detecção de nervos periféricos acometidos à época do diagnóstico correlacionou-se estatisticamente (p 0. Do mesmo modo, correlacionou-se significativamente (p < 0,05 com a ocorrência de neurites, durante a poliquimioterapia e no acompanhamento subseqüente (período médio de seguimento dos pacientes de 64,6 meses, a partir do diagnóstico. CONCLUSÃO: Sublinha-se a necessidade de realização de cuidadoso exame dos nervos periféricos por ocasião do diagnóstico, tanto para uma maior atenção para incapacidades já instaladas, quanto com relação à prevenção de incapacidades posteriores. Os profissionais que lidam com os portadores desta enfermidade devem estar atentos ao acometimento neurológico inicial por constituir fator de suscetibilidade às neurites e seqüelas neurológicas.

Roles of ADAM13-regulated Wnt activity in early Xenopus eye development

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Wei, Shuo; Xu, Guofeng; Bridges, Lance C.; Williams, Phoebe; Nakayama, Takuya; Shah, Anoop; Grainger, Robert M.; White, Judith M.; DeSimone, Douglas W.

2012-01-01

Pericellular proteolysis by ADAM family metalloproteinases has been widely implicated in cell signaling and development. We recently found that Xenopus ADAM13, an ADAM metalloproteinase, is required for activation of canonical Wnt signaling during cranial neural crest (CNC) induction by regulating a novel crosstalk between Wnt and ephrin B (EfnB) signaling pathways (Wei et al., 2010b). In the present study we show that the metalloproteinase activity of ADAM13 also plays important roles in eye development in X. tropicalis. Knockdown of ADAM13 results in reduced expression of eye field markers pax6 and rx1, as well as that of the pan-neural marker sox2. Activation of canonical Wnt signaling or inhibition of forward EfnB signaling rescues the eye defects caused by loss of ADAM13, suggesting that ADAM13 functions through regulation of the EfnB-Wnt pathway interaction. Downstream of Wnt, the head inducer Cerberus was identified as an effector that mediates ADAM13 function in early eye field formation. Furthermore, ectopic expression of the Wnt target gene snail2 restores cerberus expression and rescues the eye defects caused by ADAM13 knockdown. Together these data suggest an important role of ADAM13-regulated Wnt activity in eye development in Xenopus. PMID:22227340

SHIP-1 Increases Early Oxidative Burst and Regulates Phagosome Maturation in Macrophages1

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Kamen, Lynn A.; Levinsohn, Jonathan; Cadwallader, Amy; Tridandapani, Susheela; Swanson, Joel A.

2010-01-01

Although the inositol phosphatase SHIP-1 is generally thought to inhibit signaling for Fc receptor-mediated phagocytosis, the product of its activity, phosphatidylinositol 3,4 bisphosphate (PI(3,4)P2) has been implicated in activation of the NADPH oxidase. This suggests that SHIP-1 positively regulates generation of reactive oxygen species after phagocytosis. To examine how SHIP-1 activity contributes to Fc receptor-mediated phagocytosis, we measured and compared phospholipid dynamics, membrane trafficking and the oxidative burst in macrophages from SHIP-1-deficient and wild-type mice. SHIP-1-deficient macrophages showed significantly elevated ratios of PI(3,4,5) P3 to PI(3,4)P2 on phagosomal membranes. Imaging reactive oxygen intermediate activities in phagosomes revealed decreased early NADPH oxidase activity in SHIP-1-deficient macrophages. SHIP-1-deficiency also altered later stages of phagosome maturation, as indicated by the persistent elevation of PI(3)P and the early localization of Rab5a to phagosomes. These direct measurements of individual organelles indicate that phagosomal SHIP-1 enhances the early oxidative burst through localized alteration of the membrane 3′ phosphoinositide composition. PMID:18490750

Global regulation of mRNA translation and stability in the early Drosophila embryo by the Smaug RNA-binding protein.

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Chen, Linan; Dumelie, Jason G; Li, Xiao; Cheng, Matthew Hk; Yang, Zhiyong; Laver, John D; Siddiqui, Najeeb U; Westwood, J Timothy; Morris, Quaid; Lipshitz, Howard D; Smibert, Craig A

2014-01-07

Smaug is an RNA-binding protein that induces the degradation and represses the translation of mRNAs in the early Drosophila embryo. Smaug has two identified direct target mRNAs that it differentially regulates: nanos and Hsp83. Smaug represses the translation of nanos mRNA but has only a modest effect on its stability, whereas it destabilizes Hsp83 mRNA but has no detectable effect on Hsp83 translation. Smaug is required to destabilize more than one thousand mRNAs in the early embryo, but whether these transcripts represent direct targets of Smaug is unclear and the extent of Smaug-mediated translational repression is unknown. To gain a panoramic view of Smaug function in the early embryo, we identified mRNAs that are bound to Smaug using RNA co-immunoprecipitation followed by hybridization to DNA microarrays. We also identified mRNAs that are translationally repressed by Smaug using polysome gradients and microarrays. Comparison of the bound mRNAs to those that are translationally repressed by Smaug and those that require Smaug for their degradation suggests that a large fraction of Smaug's target mRNAs are both translationally repressed and degraded by Smaug. Smaug directly regulates components of the TRiC/CCT chaperonin, the proteasome regulatory particle and lipid droplets, as well as many metabolic enzymes, including several glycolytic enzymes. Smaug plays a direct and global role in regulating the translation and stability of a large fraction of the mRNAs in the early Drosophila embryo, and has unanticipated functions in control of protein folding and degradation, lipid droplet function and metabolism.

Parental Discipline and Externalizing Behavior Problems in Early Childhood: The Roles of Moral Regulation and Child Gender

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Kerr, David C.R.; Lopez, Nestor L.; Olson, Sheryl L.; Sameroff, Arnold J.

2004-01-01

We tested whether individual differences in a component of early conscience mediated relations between parental discipline and externalizing behavior problems in 238 3.5-year-olds. Parents contributed assessments of discipline practices and child moral regulation. Observations of children's behavioral restraint supplemented parental reports.…

End-Binding Protein 1 (EB1) Up-regulation is an Early Event in Colorectal Carcinogenesis

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Stypula-Cyrus, Yolanda; Mutyal, Nikhil N.; Cruz, Mart Angelo Dela; Kunte, Dhananjay P.; Radosevich, Andrew J.; Wali, Ramesh; Roy, Hemant K.; Backman, Vadim

2014-01-01

End-binding protein (EB1) is a microtubule protein that binds to the tumor suppressor adenomatous polyposis coli (APC). While EB1 is implicated as a potential oncogene, its role in cancer progression is unknown. Therefore, we analyzed EB1/APC expression at the earliest stages of colorectal carcinogenesis and in the uninvolved mucosa ("field effect") of human and animal tissue. We also performed siRNA-knockdown in colon cancer cell lines. EB1 is up-regulated in early and field carcinogenesis in the colon, and the cellular/nano-architectural effect of EB1 knockdown depended on the genetic context. Thus, dysregulation of EB1 is an important early event in colon carcinogenesis. PMID:24492008

Executive Function in Adolescence: Associations with Child and Family Risk Factors and Self-Regulation in Early Childhood

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Berthelsen, Donna; Hayes, Nicole; White, Sonia L. J.; Williams, Kate E.

2017-01-01

Executive functions are important higher-order cognitive skills for goal-directed thought and action. These capacities contribute to successful school achievement and lifelong wellbeing. The importance of executive functions to children’s education begins in early childhood and continues throughout development. This study explores contributions of child and family factors in early childhood to the development of executive function in adolescence. Analyses draw on data from the nationally representative study, Growing up in Australia: The Longitudinal Study of Australian Children. Participants are 4819 children in the Kindergarten Cohort who were recruited at age 4–5 years. Path analyses were employed to examine contributions of early childhood factors, including family socio-economic position (SEP), parenting behaviors, maternal mental health, and a child behavioral risk index, to the development of executive function in adolescence. The influence of children’s early self-regulatory behaviors (attentional regulation at 4–5 years and approaches to learning at 6–7 years) were also taken into account. A composite score for the outcome measure of executive function was constructed from scores on three Cogstate computerized tasks for assessing cognition and measured visual attention, visual working memory, and spatial problem-solving. Covariates included child gender, age at assessment of executive function, Aboriginal and Torres Strait Islander status, speaking a language other than English at home, and child’s receptive vocabulary skills. There were significant indirect effects involving child and family risk factors measured at 4–5 years on executive function at age 14–15 years, mediated by measures of self-regulatory behavior. Child behavioral risk, family SEP and parenting behaviors (anger, warmth, and consistency) were associated with attentional regulation at 4–5 years which, in turn, was significantly associated with approaches to learning at 6

Executive Function in Adolescence: Associations with Child and Family Risk Factors and Self-Regulation in Early Childhood

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Donna Berthelsen

2017-06-01

Full Text Available Executive functions are important higher-order cognitive skills for goal-directed thought and action. These capacities contribute to successful school achievement and lifelong wellbeing. The importance of executive functions to children’s education begins in early childhood and continues throughout development. This study explores contributions of child and family factors in early childhood to the development of executive function in adolescence. Analyses draw on data from the nationally representative study, Growing up in Australia: The Longitudinal Study of Australian Children. Participants are 4819 children in the Kindergarten Cohort who were recruited at age 4–5 years. Path analyses were employed to examine contributions of early childhood factors, including family socio-economic position (SEP, parenting behaviors, maternal mental health, and a child behavioral risk index, to the development of executive function in adolescence. The influence of children’s early self-regulatory behaviors (attentional regulation at 4–5 years and approaches to learning at 6–7 years were also taken into account. A composite score for the outcome measure of executive function was constructed from scores on three Cogstate computerized tasks for assessing cognition and measured visual attention, visual working memory, and spatial problem-solving. Covariates included child gender, age at assessment of executive function, Aboriginal and Torres Strait Islander status, speaking a language other than English at home, and child’s receptive vocabulary skills. There were significant indirect effects involving child and family risk factors measured at 4–5 years on executive function at age 14–15 years, mediated by measures of self-regulatory behavior. Child behavioral risk, family SEP and parenting behaviors (anger, warmth, and consistency were associated with attentional regulation at 4–5 years which, in turn, was significantly associated with approaches

An Empathetic Beginning in Education: Exploring the Prospects of Self-Regulation Skills on Pro-Social Behaviour in the Early Childhood Environment

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Willis, Elizabeth

2016-01-01

One avenue substantially researched and supported in early childhood research is the importance and the cultivation of self-regulation skills in the classroom. Most educational research on self-regulation skills has illustrated the importance between the enhancement of these skills and long-term academic success. Notwithstanding, there is little…

Family Interactions, Exposure to Violence, and Emotion Regulation: Perceptions of Children and Early Adolescents at Risk

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Houltberg, Benjamin J.; Henry, Carolyn S.; Morris, Amanda Sheffield

2012-01-01

This study examined the protective nature of youth reports of family interactions in relation to perceived exposure to violence and anger regulation in 84 children and early adolescents (mean age of 10.5; 7-15 years old) primarily from ethnic minority groups and living in high-risk communities in a large southwestern city. Path analysis and…

APP with Kunitz type protease inhibitor domain (KPI) correlates with neuritic plaque density but not with cortical synaptophysin immunoreactivity in Alzheimer's disease and non-demented aged subjects: a multifactorial analysis.

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Zhan, S S; Sandbrink, R; Beyreuther, K; Schmitt, H P

1995-01-01

The formation of beta A4 amyloid protein in neuritic plaques in Alzheimer's disease (AD) and advanced age is a complex process that involves a number of both cellular and molecular mechanisms, the interrelations of which are not yet completely understood. We have examined quantitatively, in AD and aged controls an extended spectrum of amyloid plaque-related cellular and molecular factors and the cortical synaptophysin immunoreactivity (synaptic density) in order to check for interrelations between them by multifactorial analysis. In 3 cases of senile dementia of the Alzheimer type (SDAT) aged 72, 80 and 82 years, and 9 controls aged 43-88 (mean age 65) years, the cortical synaptophysin immunoreactivity was assessed, together with the numbers of neurons, astrocytes and microglial cells, senile plaques, of tangle-bearing neurons, and the amount of beta A4 amyloid precursor protein (APP) with and without the Kunitz type serine protease inhibitor (KPI) domain. The main results were: APP including the KPI domain (KPI-APP) correlated with the number of neuritic plaques, regardless of whether they occurred in SDAT or non-demented controls. There was no significant difference in the amount of KPI-APP between SDAT and controls. Conversely, APP695 (without KPI) was significantly reduced in SDAT. KPI-APP did not correlate with the synaptophysin immunoreactivity (RGVA), while APP695 showed a significant correlation with the latter in all evaluations. It also correlated with the neuron counts, which was not true for KPI-APP. These results support previous findings indicating that KPI-APP is an important local factor for amyloid deposition in the neuritic plaques, both in AD and in non-demented aged people. On the contrary, KPI-APP does not seem to be significantly involved in the mechanisms of synaptic change outside of the plaques.

Individual differences in the development of early peer aggression: Integrating contributions of self-regulation, theory of mind, and parenting

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OLSON, SHERYL L.; LOPEZ-DURAN, NESTOR; LUNKENHEIMER, ERIKA S.; CHANG, HYEIN; SAMEROFF, ARNOLD J.

2014-01-01

This prospective longitudinal study focused on self-regulatory, social–cognitive, and parenting precursors of individual differences in children’s peer-directed aggression at early school age. Participants were 1993-year-old boys and girls who were reassessed following the transition to kindergarten (5.5–6 years). Peer aggression was assessed in preschool and school settings using naturalistic observations and teacher reports. Children’s self-regulation abilities and theory of mind understanding were assessed during a laboratory visit, and parenting risk (corporal punishment and low warmth/responsiveness) was assessed using interview-based and questionnaire measures. Individual differences in children’s peer aggression were moderately stable across the preschool to school transition. Preschool-age children who manifested high levels of aggressive peer interactions also showed lower levels of self-regulation and theory of mind understanding, and experienced higher levels of adverse parenting than others. Our main finding was that early corporal punishment was associated with increased levels of peer aggression across the transition from preschool to school, as was the interaction between low maternal emotional support and children’s early delays in theory of mind understanding. These data highlight the need for family-directed preventive efforts during the early preschool years. PMID:21262052

A Longitudinal Study for the Empirical Validation of an Etiopathogenetic Model of Internet Addiction in Adolescence Based on Early Emotion Regulation

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Silvia Cimino

2018-01-01

Full Text Available Several etiopathogenetic models have been conceptualized for the onset of Internet Addiction (IA. However, no study had evaluated the possible predictive effect of early emotion regulation strategies on the development of IA in adolescence. In a sample of N=142 adolescents with Internet Addiction, this twelve-year longitudinal study aimed at verifying whether and how emotion regulation strategies (self-focused versus other-focused at two years of age were predictive of school-age children’s internalizing/externalizing symptoms, which in turn fostered Internet Addiction (compulsive use of the Web versus distressed use in adolescence. Our results confirmed our hypotheses demonstrating that early emotion regulation has an impact on the emotional-behavioral functioning in middle childhood (8 years of age, which in turn has an influence on the onset of IA in adolescence. Moreover, our results showed a strong, direct statistical link between the characteristics of emotion regulation strategies in infancy and IA in adolescence. These results indicate that a common root of unbalanced emotion regulation could lead to two different manifestations of Internet Addiction in youths and could be useful in the assessment and treatment of adolescents with IA.

Early vertebrate origin and diversification of small transmembrane regulators of cellular ion transport.

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Pirkmajer, Sergej; Kirchner, Henriette; Lundell, Leonidas S; Zelenin, Pavel V; Zierath, Juleen R; Makarova, Kira S; Wolf, Yuri I; Chibalin, Alexander V

2017-07-15

Small transmembrane proteins such as FXYDs, which interact with Na + ,K + -ATPase, and the micropeptides that interact with sarco/endoplasmic reticulum Ca 2+ -ATPase play fundamental roles in regulation of ion transport in vertebrates. Uncertain evolutionary origins and phylogenetic relationships among these regulators of ion transport have led to inconsistencies in their classification across vertebrate species, thus hampering comparative studies of their functions. We discovered the first FXYD homologue in sea lamprey, a basal jawless vertebrate, which suggests small transmembrane regulators of ion transport emerged early in the vertebrate lineage. We also identified 13 gene subfamilies of FXYDs and propose a revised, phylogeny-based FXYD classification that is consistent across vertebrate species. These findings provide an improved framework for investigating physiological and pathophysiological functions of small transmembrane regulators of ion transport. Small transmembrane proteins are important for regulation of cellular ion transport. The most prominent among these are members of the FXYD family (FXYD1-12), which regulate Na + ,K + -ATPase, and phospholamban, sarcolipin, myoregulin and DWORF, which regulate the sarco/endoplasmic reticulum Ca 2+ -ATPase (SERCA). FXYDs and regulators of SERCA are present in fishes, as well as terrestrial vertebrates; however, their evolutionary origins and phylogenetic relationships are obscure, thus hampering comparative physiological studies. Here we discovered that sea lamprey (Petromyzon marinus), a representative of extant jawless vertebrates (Cyclostomata), expresses an FXYD homologue, which strongly suggests that FXYDs predate the emergence of fishes and other jawed vertebrates (Gnathostomata). Using a combination of sequence-based phylogenetic analysis and conservation of local chromosome context, we determined that FXYDs markedly diversified in the lineages leading to cartilaginous fishes (Chondrichthyes) and bony

Proneural Transcription Factors Regulate Different Steps of Cortical Neuron Migration through Rnd-Mediated Inhibition of RhoA Signaling

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Pacary, Emilie; Heng, Julian; Azzarelli, Roberta; Riou, Philippe; Castro, Diogo; Lebel-Potter, Mélanie; Parras, Carlos; Bell, Donald M.; Ridley, Anne J.; Parsons, Maddy; Guillemot, François

2011-01-01

Summary Little is known of the intracellular machinery that controls the motility of newborn neurons. We have previously shown that the proneural protein Neurog2 promotes the migration of nascent cortical neurons by inducing the expression of the atypical Rho GTPase Rnd2. Here, we show that another proneural factor, Ascl1, promotes neuronal migration in the cortex through direct regulation of a second Rnd family member, Rnd3. Both Rnd2 and Rnd3 promote neuronal migration by inhibiting RhoA signaling, but they control distinct steps of the migratory process, multipolar to bipolar transition in the intermediate zone and locomotion in the cortical plate, respectively. Interestingly, these divergent functions directly result from the distinct subcellular distributions of the two Rnd proteins. Because Rnd proteins also regulate progenitor divisions and neurite outgrowth, we propose that proneural factors, through spatiotemporal regulation of Rnd proteins, integrate the process of neuronal migration with other events in the neurogenic program. PMID:21435554

The metabolic enhancer piracetam ameliorates the impairment of mitochondrial function and neurite outgrowth induced by ß-amyloid peptide

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Kurz, C; Ungerer, I; Lipka, U; Kirr, S; Schütt, T; Eckert, A; Leuner, K; Müller, WE

2010-01-01

Background and purpose: β-Amyloid peptide (Aβ) is implicated in the pathogenesis of Alzheimer's disease by initiating a cascade of events from mitochondrial dysfunction to neuronal death. The metabolic enhancer piracetam has been shown to improve mitochondrial dysfunction following brain aging and experimentally induced oxidative stress. Experimental approach: We used cell lines (PC12 and HEK cells) and murine dissociated brain cells. The protective effects of piracetam in vitro and ex vivo on Aβ-induced impairment of mitochondrial function (as mitochondrial membrane potential and ATP production), on secretion of soluble Aβ and on neurite outgrowth in PC12 cells were investigated. Key results: Piracetam improves mitochondrial function of PC12 cells and acutely dissociated brain cells from young NMRI mice following exposure to extracellular Aβ1-42. Similar protective effects against Aβ1-42 were observed in dissociated brain cells from aged NMRI mice, or mice transgenic for mutant human amyloid precursor protein (APP) treated with piracetam for 14 days. Soluble Aβ load was markedly diminished in the brain of those animals after treatment with piracetam. Aβ production by HEK cells stably transfected with mutant human APP was elevated by oxidative stress and this was reduced by piracetam. Impairment of neuritogenesis is an important consequence of Aβ-induced mitochondrial dysfunction and Aβ-induced reduction of neurite growth in PC12 cells was substantially improved by piracetam. Conclusion and implications: Our findings strongly support the concept of improving mitochondrial function as an approach to ameliorate the detrimental effects of Aβ on brain function. This article is commented on by Moncada, pp. 217–219 of this issue. To view this commentary visit http://dx.doi.org/10.1111/j.1476-5381.2010.00706.x and to view related papers by Pravdic et al. and Puerta et al. visit http://dx.doi.org/10.1111/j.1476-5381.2010.00698.x and http://dx.doi.org/10.1111/j

The Subcellular Dynamics of the Gs-Linked Receptor GPR3 Contribute to the Local Activation of PKA in Cerebellar Granular Neurons.

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Miyagi, Tatsuhiro; Tanaka, Shigeru; Hide, Izumi; Shirafuji, Toshihiko; Sakai, Norio

2016-01-01

G-protein-coupled receptor (GPR) 3 is a member of the GPR family that constitutively activates adenylate cyclase. We have reported that the expression of GPR3 in cerebellar granular neurons (CGNs) contributes to neurite outgrowth and modulates neuronal proliferation and survival. To further identify its role, we have analyzed the precise distribution and local functions of GPR3 in neurons. The fluorescently tagged GPR3 protein was distributed in the plasma membrane, the Golgi body, and the endosomes. In addition, we have revealed that the plasma membrane expression of GPR3 functionally up-regulated the levels of PKA, as measured by a PKA FRET indicator. Next, we asked if the PKA activity was modulated by the expression of GPR3 in CGNs. PKA activity was highly modulated at the neurite tips compared to the soma. In addition, the PKA activity at the neurite tips was up-regulated when GPR3 was transfected into the cells. However, local PKA activity was decreased when endogenous GPR3 was suppressed by a GPR3 siRNA. Finally, we determined the local dynamics of GPR3 in CGNs using time-lapse analysis. Surprisingly, the fluorescent GPR3 puncta were transported along the neurite in both directions over time. In addition, the anterograde movements of the GPR3 puncta in the neurite were significantly inhibited by actin or microtubule polymerization inhibitors and were also disturbed by the Myosin II inhibitor blebbistatin. Moreover, the PKA activity at the tips of the neurites was decreased when blebbistatin was administered. These results suggested that GPR3 was transported along the neurite and contributed to the local activation of PKA in CGN development. The local dynamics of GPR3 in CGNs may affect local neuronal functions, including neuronal differentiation and maturation.

Polo-Like Kinase 2 is Dynamically Regulated to Coordinate Proliferation and Early Lineage Specification Downstream of Yes-Associated Protein 1 in Cardiac Progenitor Cells.

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Mochizuki, Michika; Lorenz, Vera; Ivanek, Robert; Della Verde, Giacomo; Gaudiello, Emanuele; Marsano, Anna; Pfister, Otmar; Kuster, Gabriela M

2017-10-24

Recent studies suggest that adult cardiac progenitor cells (CPCs) can produce new cardiac cells. Such cell formation requires an intricate coordination of progenitor cell proliferation and commitment, but the molecular cues responsible for this regulation in CPCs are ill defined. Extracellular matrix components are important instructors of cell fate. Using laminin and fibronectin, we induced two slightly distinct CPC phenotypes differing in proliferation rate and commitment status and analyzed the early transcriptomic response to CPC adhesion (<2 hours). Ninety-four genes were differentially regulated on laminin versus fibronectin, consisting of mostly downregulated genes that were enriched for Yes-associated protein (YAP) conserved signature and TEA domain family member 1 (TEAD1)-related genes. This early gene regulation was preceded by the rapid cytosolic sequestration and degradation of YAP on laminin. Among the most strongly regulated genes was polo-like kinase 2 ( Plk2 ). Plk2 expression depended on YAP stability and was enhanced in CPCs transfected with a nuclear-targeted mutant YAP. Phenotypically, the early downregulation of Plk2 on laminin was succeeded by lower cell proliferation, enhanced lineage gene expression (24 hours), and facilitated differentiation (3 weeks) compared with fibronectin. Finally, overexpression of Plk2 enhanced CPC proliferation and knockdown of Plk2 induced the expression of lineage genes. Plk2 acts as coordinator of cell proliferation and early lineage commitment in CPCs. The rapid downregulation of Plk2 on YAP inactivation marks a switch towards enhanced commitment and facilitated differentiation. These findings link early gene regulation to cell fate and provide novel insights into how CPC proliferation and differentiation are orchestrated. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Evidence of an IFN-γ by early life stress interaction in the regulation of amygdala reactivity to emotional stimuli.

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Redlich, Ronny; Stacey, David; Opel, Nils; Grotegerd, Dominik; Dohm, Katharina; Kugel, Harald; Heindel, Walter; Arolt, Volker; Baune, Bernhard T; Dannlowski, Udo

2015-12-01

Since numerous studies have found that exposure to early life stress leads to increased peripheral inflammation and psychiatric disease, it is thought that peripheral immune activation precedes and possibly mediates the onset of stress-associated psychiatric disease. Despite early studies, IFNγ has received little attention relative to other inflammatory cytokines in the context of the pathophysiology of affective disorders. Neuroimaging endophenotypes have emerged recently as a promising means of elucidating these types of complex relationships including the modeling of the interaction between environmental factors and genetic predisposition. Here we investigate the GxE relationship between early-life stress and genetic variants of IFNγ on emotion processing. To investigate the impact of the relationship between genetic variants of IFNγ (rs1861494, rs2069718, rs2430561) and early life stress on emotion processing, a sample of healthy adults (n=409) undergoing an emotional faces paradigm in an fMRI study were genotyped and analysed. Information on early life stress was obtained via Childhood Trauma Questionnaire (CTQ). A positive association between early life stress and amygdala reactivity was found. Specifically, the main effect of genotype of rs1861494 on amygdala reactivity indicates a higher neural response in C allele carriers compared to T homozygotes, while we did not find main effects of rs2069718 and rs2430561. Importantly, interaction analyses revealed a specific interaction between IFNγ genotype (rs1861494) and early life stress affecting amygdala reactivity to emotional faces, resulting from a positive association between CTQ scores and amygdala reactivity in C allele carriers while this association was absent in T homozygotes. Our findings indicate that firstly the genetic variant of IFNγ (rs1861494) is involved with the regulation of amygdala reactivity to emotional stimuli and secondly, that this genetic variant moderates effects of early life

Regulation of protein synthesis during sea urchin early development

International Nuclear Information System (INIS)

Kelso, L.C.

1989-01-01

Fertilization of the sea urchin egg results in a 20-40 fold increase in the rate of protein synthesis. The masked message hypothesis proposes that mRNAs are masked or unavailable for translation in the egg. We devised an in vivo assay to test this hypothesis. Our results show that masked mRNAs limit protein synthesis in the unfertilized egg. In addition, we show that protein synthesis is also regulated at the level of translational machinery. Following fertilization is a period of rapid cell divisions. This period, known as the rapid cleavage stage, is characterized by the transient synthesis of a novel set of proteins. The synthesis of these proteins is programmed by maternal mRNAs stored in the unfertilized egg. To study the behavior of these mRNAs, we prepared a cDNA library from polysomal poly (A+) RNA from 2-hour embryos. [ 32 P] labeled probes, prepared from the cDNA library, were used to monitor the levels of individual mRNAs in polysomes at fertilization and during early development

Steroidogenesis and early response gene expression in MA-10 Leydig tumor cells following heterologous receptor down-regulation and cellular desensitization

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Tsuey-Ming Chen

2016-03-01

Full Text Available The Leydig tumor cell line, MA-10, expresses the luteinizing hormone receptor, a G protein-coupled receptor that, when activated with luteinizing hormone or chorionic gonadotropin (CG, stimulates cAMP production and subsequent steroidogenesis, notably progesterone. These cells also respond to epidermal growth factor (EGF and phorbol esters with increased steroid biosynthesis. In order to probe the intracellular pathways along with heterologous receptor down-regulation and cellular desensitization, cells were preincubated with EGF or phorbol esters and then challenged with CG, EGF, dibutryl-cyclic AMP, and a phorbol ester. Relative receptor numbers, steroid biosynthesis, and expression of the early response genes, JUNB and c-FOS, were measured. It was found that in all cases but one receptor down-regulation and decreased progesterone production were closely coupled under the conditions used; the exception involved preincubation of the cells with EGF followed by addition of CG where the CG-mediated stimulation of steroidogenesis was considerably lower than the level of receptor down-regulation. In a number of instances JUNB and c-FOS expression paralleled the decreases in receptor number and progesterone production, while in some cases these early response genes were affected little if at all by the changes in receptor number. This finding may indicate that even low levels of activated signaling kinases, e.g. protein kinase A, protein kinase C, or receptor tyrosine kinase, may suffice to yield good expression of JUNB and c-FOS, or it may suggest alternative pathways for regulating expression of these two early response genes.

Phospholipase A2 activation as a therapeutic approach for cognitive enhancement in early-stage Alzheimer disease.

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Schaeffer, Evelin L; Forlenza, Orestes V; Gattaz, Wagner F

2009-01-01

Alzheimer disease (AD) is the leading cause of dementia in the elderly and has no known cure. Evidence suggests that reduced activity of specific subtypes of intracellular phospholipases A2 (cPLA2 and iPLA2) is an early event in AD and may contribute to memory impairment and neuropathology in the disease. The objective of this study was to review the literature focusing on the therapeutic role of PLA2 stimulation by cognitive training and positive modulators, or of supplementation with arachidonic acid (PLA2 product) in facilitating memory function and synaptic transmission and plasticity in either research animals or human subjects. MEDLINE database was searched (no date restrictions) for published articles using the keywords Alzheimer disease (mild, moderate, severe), mild cognitive impairment, healthy elderly, rats, mice, phospholipase A(2), phospholipid metabolism, phosphatidylcholine, arachidonic acid, cognitive training, learning, memory, long-term potentiation, protein kinases, dietary lipid compounds, cell proliferation, neurogenesis, and neuritogenesis. Reference lists of the identified articles were checked to select additional studies of interest. Overall, the data suggest that PLA2 activation is induced in the healthy brain during learning and memory. Furthermore, learning seems to regulate endogenous neurogenesis, which has been observed in AD brains. Finally, PLA2 appears to be implicated in homeostatic processes related to neurite outgrowth and differentiation in both neurodevelopmental processes and response to neuronal injury. The use of positive modulators of PLA2 (especially of cPLA2 and iPLA2) or supplementation with dietary lipid compounds (e.g., arachidonic acid) in combination with cognitive training could be a valuable therapeutic strategy for cognitive enhancement in early-stage AD.

Role of glial cell line-derived neurotrophic factor (GDNF)-neural cell adhesion molecule (NCAM) interactions in induction of neurite outgrowth and identification of a binding site for NCAM in the heel region of GDNF

DEFF Research Database (Denmark)

Nielsen, Janne; Gotfryd, Kamil; Li, Shizhong

2009-01-01

NCAM-induced neurite outgrowth by being independent of NCAM polysialylation. Additionally, we investigated the structural basis for GDNF-NCAM interactions and find that NCAM Ig3 is necessary for GDNF binding. Furthermore, we identify within the heel region of GDNF a binding site for NCAM...

MicroRNA-212 post-transcriptionally regulates oocyte-specific basic-helix-loop-helix transcription factor, factor in the germline alpha (FIGLA, during bovine early embryogenesis.

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Swamy K Tripurani

Full Text Available Factor in the germline alpha (FIGLA is an oocyte-specific basic helix-loop-helix transcription factor essential for primordial follicle formation and expression of many genes required for folliculogenesis, fertilization and early embryonic survival. Here we report the characterization of bovine FIGLA gene and its regulation during early embryogenesis. Bovine FIGLA mRNA expression is restricted to gonads and is detected in fetal ovaries harvested as early as 90 days of gestation. FIGLA mRNA and protein are abundant in germinal vesicle and metaphase II stage oocytes, as well as in embryos from pronuclear to eight-cell stage but barely detectable at morula and blastocyst stages, suggesting that FIGLA might be a maternal effect gene. Recent studies in zebrafish and mice have highlighted the importance of non-coding small RNAs (microRNAs as key regulatory molecules targeting maternal mRNAs for degradation during embryonic development. We hypothesized that FIGLA, as a maternal transcript, is regulated by microRNAs during early embryogenesis. Computational predictions identified a potential microRNA recognition element (MRE for miR-212 in the 3' UTR of the bovine FIGLA mRNA. Bovine miR-212 is expressed in oocytes and tends to increase in four-cell and eight-cell stage embryos followed by a decline at morula and blastocyst stages. Transient transfection and reporter assays revealed that miR-212 represses the expression of FIGLA in a MRE dependent manner. In addition, ectopic expression of miR-212 mimic in bovine early embryos dramatically reduced the expression of FIGLA protein. Collectively, our results demonstrate that FIGLA is temporally regulated during bovine early embryogenesis and miR-212 is an important negative regulator of FIGLA during the maternal to zygotic transition in bovine embryos.

Regulation of radiation-induced apoptosis by early growth response-1 gene in solid tumors

International Nuclear Information System (INIS)

Ahmed, M.

2003-01-01

Ionizing radiation exposure is associated with activation of certain immediate-early genes that function as transcription factors. These include members of jun or fos and early growth response (EGR) gene families. In particular, the functional role of EGR-1 in radiation-induced signaling is pivotal since the promoter of EGR-1 contains radiation-inducible CArG DNA sequences. The Egr-1 gene belongs to a family of Egr genes that includes EGR-2, EGR-3, EGR-4, EGR-α and the tumor suppressor, Wilms' tumor gene product, WT1. The Egr-1 gene product, EGR-1, is a nuclear protein that contains three zinc fingers of the C 2 H 2 subtype. The EGR-1 GC-rich consensus target sequence, 5'-GCGT/GGGGCG-3' or 5'-TCCT/ACCTCCTCC-3', has been identified in the promoter regions of transcription factors, growth factors, receptors, cell cycle regulators and pro-apoptotic genes. The gene targets mediated by Egr-1 in response to ionizing radiation include TNF-α , p53, Rb and Bax, all these are effectors of apoptosis. Based on these targets, Egr-1 is a pivotal gene that initiates early signal transduction events in response to ionizing radiation leading to either growth arrest or cell death in tumor cells. There are two potential application of Egr-1 gene in therapy of cancer. First, the Egr-1 promoter contains information for appropriate spatial and temporal expression in-vivo that can be regulated by ionizing radiation to control transcription of genes that have pro-apoptotic and suicidal function. Secondly, EGR-1 protein can eliminate 'induced-radiation resistance' by inhibiting the functions of radiation-induced pro-survival genes (NFκB activity and bcl-2 expression) and activate pro-apoptotic genes (such as bax) to confer a significant radio-sensitizing effect. Together, the reported findings from my laboratory demonstrate clearly that EGR-1 is an early central gene that confers radiation sensitivity and its pro-apoptotic functions are synergized by abrogation of induced radiation

Human adipose tissue-derived multilineage progenitor cells exposed to oxidative stress induce neurite outgrowth in PC12 cells through p38 MAPK signaling

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Moriyama Mariko

2012-08-01

Full Text Available Abstract Background Adipose tissues contain populations of pluripotent mesenchymal stem cells that also secrete various cytokines and growth factors to support repair of damaged tissues. In this study, we examined the role of oxidative stress on human adipose-derived multilineage progenitor cells (hADMPCs in neurite outgrowth in cells of the rat pheochromocytoma cell line (PC12. Results We found that glutathione depletion in hADMPCs, caused by treatment with buthionine sulfoximine (BSO, resulted in the promotion of neurite outgrowth in PC12 cells through upregulation of bone morphogenetic protein 2 (BMP2 and fibroblast growth factor 2 (FGF2 transcription in, and secretion from, hADMPCs. Addition of N-acetylcysteine, a precursor of the intracellular antioxidant glutathione, suppressed the BSO-mediated upregulation of BMP2 and FGF2. Moreover, BSO treatment caused phosphorylation of p38 MAPK in hADMPCs. Inhibition of p38 MAPK was sufficient to suppress BMP2 and FGF2 expression, while this expression was significantly upregulated by overexpression of a constitutively active form of MKK6, which is an upstream molecule from p38 MAPK. Conclusions Our results clearly suggest that glutathione depletion, followed by accumulation of reactive oxygen species, stimulates the activation of p38 MAPK and subsequent expression of BMP2 and FGF2 in hADMPCs. Thus, transplantation of hADMPCs into neurodegenerative lesions such as stroke and Parkinson’s disease, in which the transplanted hADMPCs are exposed to oxidative stress, can be the basis for simple and safe therapies.

The Nun study: clinically silent AD, neuronal hypertrophy, and linguistic skills in early life.

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Iacono, D; Markesbery, W R; Gross, M; Pletnikova, O; Rudow, G; Zandi, P; Troncoso, J C

2009-09-01

It is common to find substantial Alzheimer disease (AD) lesions, i.e., neuritic beta-amyloid plaques and neurofibrillary tangles, in the autopsied brains of elderly subjects with normal cognition assessed shortly before death. We have termed this status asymptomatic AD (ASYMAD). We assessed the morphologic substrate of ASYMAD compared to mild cognitive impairment (MCI) in subjects from the Nun Study. In addition, possible correlations between linguistic abilities in early life and the presence of AD pathology with and without clinical manifestations in late life were considered. Design-based stereology was used to measure the volumes of neuronal cell bodies, nuclei, and nucleoli in the CA1 region of hippocampus (CA1). Four groups of subjects were compared: ASYMAD (n = 10), MCI (n = 5), AD (n = 10), and age-matched controls (n = 13). Linguistic ability assessed in early life was compared among all groups. A significant hypertrophy of the cell bodies (+44.9%), nuclei (+59.7%), and nucleoli (+80.2%) in the CA1 neurons was found in ASYMAD compared with MCI. Similar differences were observed with controls. Furthermore, significant higher idea density scores in early life were observed in controls and ASYMAD group compared to MCI and AD groups. 1) Neuronal hypertrophy may constitute an early cellular response to Alzheimer disease (AD) pathology or reflect compensatory mechanisms that prevent cognitive impairment despite substantial AD lesions; 2) higher idea density scores in early life are associated with intact cognition in late life despite the presence of AD lesions.

Progranulin regulates neuronal outgrowth independent of Sortilin

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Gass Jennifer

2012-07-01

Full Text Available Abstract Background Progranulin (PGRN, a widely secreted growth factor, is involved in multiple biological functions, and mutations located within the PGRN gene (GRN are a major cause of frontotemporal lobar degeneration with TDP-43-positive inclusions (FLTD-TDP. In light of recent reports suggesting PGRN functions as a protective neurotrophic factor and that sortilin (SORT1 is a neuronal receptor for PGRN, we used a Sort1-deficient (Sort1−/− murine primary hippocampal neuron model to investigate whether PGRN’s neurotrophic effects are dependent on SORT1. We sought to elucidate this relationship to determine what role SORT1, as a regulator of PGRN levels, plays in modulating PGRN’s neurotrophic effects. Results As the first group to evaluate the effect of PGRN loss in Grn knockout primary neuronal cultures, we show neurite outgrowth and branching are significantly decreased in Grn−/− neurons compared to wild-type (WT neurons. More importantly, we also demonstrate that PGRN overexpression can rescue this phenotype. However, the recovery in outgrowth is not observed following treatment with recombinant PGRN harboring missense mutations p.C139R, p.P248L or p.R432C, indicating that these mutations adversely affect the neurotrophic properties of PGRN. In addition, we also present evidence that cleavage of full-length PGRN into granulin peptides is required for increased neuronal outgrowth, suggesting that the neurotrophic functions of PGRN are contained within certain granulins. To further characterize the mechanism by which PGRN impacts neuronal morphology, we assessed the involvement of SORT1. We demonstrate that PGRN induced-outgrowth occurs in the absence of SORT1 in Sort1−/− cultures. Conclusion We demonstrate that loss of PGRN impairs proper neurite outgrowth and branching, and that exogenous PGRN alleviates this impairment. Furthermore, we determined that exogenous PGRN induces outgrowth independent of SORT1, suggesting another

Effects of early maternal distress and parenting on the development of children's self-regulation and externalizing behavior.

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Choe, Daniel Ewon; Olson, Sheryl L; Sameroff, Arnold J

2013-05-01

Emotional distress experienced by mothers increases young children's risk of externalizing problems through suboptimal parenting and child self-regulation. An integrative structural equation model tested hypotheses that mothers' parenting (i.e., low levels of inductive discipline and maternal warmth) would mediate adverse effects of early maternal distress on child effortful control, which in turn would mediate effects of maternal parenting on child externalizing behavior. This longitudinal study spanning ages 3, 6, and 10 included 241 children, mothers, and a subset of teachers. The hypothesized model was partially supported. Elevated maternal distress was associated with less inductive discipline and maternal warmth, which in turn were associated with less effortful control at age 3 but not at age 6. Inductive discipline and maternal warmth mediated adverse effects of maternal distress on children's effortful control. Less effortful control at ages 3 and 6 predicted smaller relative decreases in externalizing behavior at 6 and 10, respectively. Effortful control mediated effects of inductive discipline, but not maternal warmth, on externalizing behavior. Findings suggest elevated maternal distress increases children's risk of externalizing problems by compromising early parenting and child self-regulation.

Endocardial to myocardial notch-wnt-bmp axis regulates early heart valve development.

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Yidong Wang

Full Text Available Endocardial to mesenchymal transformation (EMT is a fundamental cellular process required for heart valve formation. Notch, Wnt and Bmp pathways are known to regulate this process. To further address how these pathways coordinate in the process, we specifically disrupted Notch1 or Jagged1 in the endocardium of mouse embryonic hearts and showed that Jagged1-Notch1 signaling in the endocardium is essential for EMT and early valvular cushion formation. qPCR and RNA in situ hybridization assays reveal that endocardial Jagged1-Notch1 signaling regulates Wnt4 expression in the atrioventricular canal (AVC endocardium and Bmp2 in the AVC myocardium. Whole embryo cultures treated with Wnt4 or Wnt inhibitory factor 1 (Wif1 show that Bmp2 expression in the AVC myocardium is dependent on Wnt activity; Wnt4 also reinstates Bmp2 expression in the AVC myocardium of endocardial Notch1 null embryos. Furthermore, while both Wnt4 and Bmp2 rescue the defective EMT resulting from Notch inhibition, Wnt4 requires Bmp for its action. These results demonstrate that Jagged1-Notch1 signaling in endocardial cells induces the expression of Wnt4, which subsequently acts as a paracrine factor to upregulate Bmp2 expression in the adjacent AVC myocardium to signal EMT.

Abnormal neural precursor cell regulation in the early postnatal Fragile X mouse hippocampus.

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Sourial, Mary; Doering, Laurie C

2017-07-01

The regulation of neural precursor cells (NPCs) is indispensable for a properly functioning brain. Abnormalities in NPC proliferation, differentiation, survival, or integration have been linked to various neurological diseases including Fragile X syndrome. Yet, no studies have examined NPCs from the early postnatal Fragile X mouse hippocampus despite the importance of this developmental time point, which marks the highest expression level of FMRP, the protein missing in Fragile X, in the rodent hippocampus and is when hippocampal NPCs have migrated to the dentate gyrus (DG) to give rise to lifelong neurogenesis. In this study, we examined NPCs from the early postnatal hippocampus and DG of Fragile X mice (Fmr1-KO). Immunocytochemistry on neurospheres showed increased Nestin expression and decreased Ki67 expression, which collectively indicated aberrant NPC biology. Intriguingly, flow cytometric analysis of the expression of the antigens CD15, CD24, CD133, GLAST, and PSA-NCAM showed a decreased proportion of neural stem cells (GLAST + CD15 + CD133 + ) and an increased proportion of neuroblasts (PSA-NCAM + CD15 + ) in the DG of P7 Fmr1-KO mice. This was mirrored by lower expression levels of Nestin and the mitotic marker phospho-histone H3 in vivo in the P9 hippocampus, as well as a decreased proportion of cells in the G 2 /M phases of the P7 DG. Thus, the absence of FMRP leads to fewer actively cycling NPCs, coinciding with a decrease in neural stem cells and an increase in neuroblasts. Together, these results show the importance of FMRP in the developing hippocampal formation and suggest abnormalities in cell cycle regulation in Fragile X. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

fNIRS evidence of prefrontal regulation of frustration in early childhood.

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Perlman, Susan B; Luna, Beatriz; Hein, Tyler C; Huppert, Theodore J

2014-01-15

The experience of frustration is common in early childhood, yet some children seem to possess a lower tolerance for frustration than others. Characterizing the biological mechanisms underlying a wide range of frustration tolerance observed in early childhood may inform maladaptive behavior and psychopathology that is associated with this construct. The goal of this study was to measure prefrontal correlates of frustration in 3-5-year-old children, who are not readily adaptable for typical neuroimaging approaches, using functional near infrared spectroscopy (fNIRS). fNIRS of frontal regions were measured as frustration was induced in children through a computer game where a desired and expected prize was "stolen" by an animated dog. A fNIRS general linear model (GLM) was used to quantify the correlation of brain regions with the task and identify areas that were statistically different between the winning and frustrating test conditions. A second-level voxel-based ANOVA analysis was then used to correlate the amplitude of each individual's brain activation with measure of parent-reported frustration. Experimental results indicated increased activity in the middle prefrontal cortex during winning of a desired prize, while lateral prefrontal cortex activity increased during frustration. Further, activity increase in lateral prefrontal cortex during frustration correlated positively with parent-reported frustration tolerance. These findings point to the role of the lateral prefrontal cortex as a potential region supporting the regulation of emotion during frustration. Copyright © 2013 Elsevier Inc. All rights reserved.

Astrocyte-to-neuron communication through integrin-engaged Thy-1/CBP/Csk/Src complex triggers neurite retraction via the RhoA/ROCK pathway.

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Maldonado, H; Calderon, C; Burgos-Bravo, F; Kobler, O; Zuschratter, W; Ramirez, O; Härtel, S; Schneider, P; Quest, A F G; Herrera-Molina, R; Leyton, L

2017-02-01

Two key proteins for cellular communication between astrocytes and neurons are αvβ3 integrin and the receptor Thy-1. Binding of these molecules in the same (cis) or on adjacent (trans) cellular membranes induces Thy-1 clustering, triggering actin cytoskeleton remodeling. Molecular events that could explain how the Thy-1-αvβ3 integrin interaction signals have only been studied separately in different cell types, and the detailed transcellular communication and signal transduction pathways involved in neuronal cytoskeleton remodeling remain unresolved. Using biochemical and genetic approaches, single-molecule tracking, and high-resolution nanoscopy, we provide evidence that upon binding to αvβ3 integrin, Thy-1 mobility decreased while Thy-1 nanocluster size increased. This occurred concomitantly with inactivation and exclusion of the non-receptor tyrosine kinase Src from the Thy-1/C-terminal Src kinase (Csk)-binding protein (CBP)/Csk complex. The Src inactivation decreased the p190Rho GTPase activating protein phosphorylation, promoting RhoA activation, cofilin, and myosin light chain II phosphorylation and, consequently, neurite shortening. Finally, silencing the adaptor CBP demonstrated that this protein was a key transducer in the Thy-1 signaling cascade. In conclusion, these data support the hypothesis that the Thy-1-CBP-Csk-Src-RhoA-ROCK axis transmitted signals from astrocytic integrin-engaged Thy-1 (trans) to the neuronal actin cytoskeleton. Importantly, the β3 integrin in neurons (cis) was not found to be crucial for neurite shortening. This is the first study to detail the signaling pathway triggered by αvβ3, the endogenous Thy-1 ligand, highlighting the role of membrane-bound integrins as trans acting ligands in astrocyte-neuron communication. Copyright © 2016 Elsevier B.V. All rights reserved.

The Cdk4-E2f1 pathway regulates early pancreas development by targeting Pdx1+ progenitors and Ngn3+ endocrine precursors

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Kim, So Yoon; Rane, Sushil G.

2011-01-01

Cell division and cell differentiation are intricately regulated processes vital to organ development. Cyclin-dependent kinases (Cdks) are master regulators of the cell cycle that orchestrate the cell division and differentiation programs. Cdk1 is essential to drive cell division and is required for the first embryonic divisions, whereas Cdks 2, 4 and 6 are dispensable for organogenesis but vital for tissue-specific cell development. Here, we illustrate an important role for Cdk4 in regulating early pancreas development. Pancreatic development involves extensive morphogenesis, proliferation and differentiation of the epithelium to give rise to the distinct cell lineages of the adult pancreas. The cell cycle molecules that specify lineage commitment within the early pancreas are unknown. We show that Cdk4 and its downstream transcription factor E2f1 regulate mouse pancreas development prior to and during the secondary transition. Cdk4 deficiency reduces embryonic pancreas size owing to impaired mesenchyme development and fewer Pdx1+ pancreatic progenitor cells. Expression of activated Cdk4R24C kinase leads to increased Nkx2.2+ and Nkx6.1+ cells and a rise in the number and proliferation of Ngn3+ endocrine precursors, resulting in expansion of the β cell lineage. We show that E2f1 binds and activates the Ngn3 promoter to modulate Ngn3 expression levels in the embryonic pancreas in a Cdk4-dependent manner. These results suggest that Cdk4 promotes β cell development by directing E2f1-mediated activation of Ngn3 and increasing the pool of endocrine precursors, and identify Cdk4 as an important regulator of early pancreas development that modulates the proliferation potential of pancreatic progenitors and endocrine precursors. PMID:21490060

Pedagogical Work, Stress Regulation and Work-Related Well-Being among Early Childhood Professionals in Integrated Special Day-Care Groups

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Nislin, Mari A.; Sajaniemi, Nina K.; Sims, Margaret; Suhonen, Eira; Maldonado Montero, Enrique F.; Hirvonen, Ari; Hyttinen, Sirpa

2016-01-01

The aim of this study was to investigate the relationship between early childhood professionals' (ECPs) stress regulation (using salivary cortisol and alpha-amylase [AA] measurements), work engagement and the quality of their pedagogical work in integrated special day-care groups. Participants were 89 ECPs from 21 integrated special day-care…

Neurite orientation dispersion and density imaging in the substantia nigra in idiopathic Parkinson disease

International Nuclear Information System (INIS)

Kamagata, Koji; Suzuki, Michimasa; Hori, Masaaki; Kumamaru, Kanako K.; Aoki, Shigeki; Hatano, Taku; Okuzumi, Ayami; Motoi, Yumiko; Hattori, Nobutaka; Abe, Osamu; Shimoji, Keigo; Kamiya, Kouhei

2016-01-01

We used neurite orientation dispersion and density imaging (NODDI) to quantify changes in the substantia nigra pars compacta (SNpc) and striatum in Parkinson disease (PD). Diffusion-weighted magnetic resonance images were acquired from 58 PD patients and 36 age- and sex-matched controls. The intracellular volume fraction (Vic), orientation dispersion index (OD), and isotropic volume fraction (Viso) of the basal ganglia were compared between groups. Multivariate logistic regression analysis determined which diffusion parameters were independent predictors of PD. Receiver operating characteristic (ROC) analysis compared the diagnostic accuracies of the evaluated indices. Pearson coefficient analysis correlated each diffusional parameter with disease severity. Vic in the contralateral SNpc and putamen were significantly lower in PD patients than in healthy controls (P < 0.00058). Vic and OD in the SNpc and putamen showed significant negative correlations (P < 0.05) with disease severity. Multivariate logistic analysis revealed that Vic (P = 0.0000046) and mean diffusivity (P = 0.019) in the contralateral SNpc were the independent predictors of PD. In the ROC analysis, Vic in the contralateral SNpc showed the best diagnostic performance (mean cutoff, 0.62; sensitivity, 0.88; specificity, 0.83). NODDI is likely to be useful for diagnosing PD and assessing its progression. (orig.)

Differential regulation of axon outgrowth and reinnervation by neurotrophin-3 and neurotrophin-4 in the hippocampal formation.

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Hechler, Daniel; Boato, Francesco; Nitsch, Robert; Hendrix, Sven

2010-08-01

In this study, we investigated the hypothesis whether neurotrophins have a differential influence on neurite growth from the entorhinal cortex depending on the presence or absence of hippocampal target tissue. We investigated organotypic brain slices derived from the entorhinal-hippocampal system to analyze the effects of endogenous and recombinant neurotrophin-3 (NT-3) and neurotrophin-4 (NT-4) on neurite outgrowth and reinnervation. In the reinnervation assay, entorhinal cortex explants of transgenic mice expressing enhanced green fluorescent protein (EGFP) were co-cultured with wild-type hippocampi under the influence of recombinant NT-3 and NT-4 (500 ng/ml). Both recombinant NT-3 and NT-4 significantly increased the growth of EGFP+ nerve fibers into the target tissue. Consistently, reinnervation of the hippocampi of NT-4(-/-) and NT-3(+/-)NT-4(-/-) mice was substantially reduced. In contrast, the outgrowth assay did not exhibit reduction in axon outgrowth of NT-4(-/-) or NT-3(+/-)NT-4(-/-) cortex explants, while the application of recombinant NT-3 (500 ng/ml) induced a significant increase in the neurite extension of cortex explants. Recombinant NT-4 had no effect. In summary, only recombinant NT-3 stimulates axon outgrowth from cortex explants, while both endogenous and recombinant NT-3 and NT-4 synergistically promote reinnervation of the denervated hippocampus. These results suggest that endogenous and exogenous NT-3 and NT-4 differentially influence neurite growth depending on the presence or absence of target tissue.

Early bovine embryos regulate oviduct epithelial cell gene expression during in vitro co-culture.

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Schmaltz-Panneau, Barbara; Cordova, Amanda; Dhorne-Pollet, Sophie; Hennequet-Antier, Christelle; Uzbekova, Sveltlana; Martinot, Emmanuelle; Doret, Sarah; Martin, Patrice; Mermillod, Pascal; Locatelli, Yann

2014-10-01

In mammals, the oviduct may participate to the regulation of early embryo development. In vitro co-culture of early bovine embryos with bovine oviduct epithelial cells (BOEC) has been largely used to mimic the maternal environment. However, the mechanisms of BOEC action have not been clearly elucidated yet. The aim of this study was to determine the response of BOEC cultures to the presence of developing bovine embryos. A 21,581-element bovine oligonucleotide array was used compare the gene expression profiles of confluent BOEC cultured for 8 days with or without embryos. This study revealed 34 differentially expressed genes (DEG). Of these 34 genes, IFI6, ISG15, MX1, IFI27, IFI44, RSAD2, IFITM1, EPSTI1, USP18, IFIT5, and STAT1 expression increased to the greatest extent due to the presence of embryos with a major impact on antiviral and immune response. Among the mRNAs at least 25 are already described as induced by interferons. In addition, transcript levels of new candidate genes involved in the regulation of transcription, modulation of the maternal immune system and endometrial remodeling were found to be increased. We selected 7 genes and confirmed their differential expression by quantitative RT-PCR. The immunofluorescence imaging of cellular localization of STAT1 protein in BOEC showed a nuclear translocation in the presence of embryos, suggesting the activation of interferon signaling pathway. This first systematic study of BOEC transcriptome changes in response to the presence of embryos in cattle provides some evidences that these cells are able to adapt their transcriptomic profile in response to embryo signaling. Copyright © 2014 Elsevier B.V. All rights reserved.

Early peroxisome proliferator-activated receptor gamma regulated genes involved in expansion of pancreatic beta cell mass

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Vivas Yurena

2011-12-01

Full Text Available Abstract Background The progression towards type 2 diabetes depends on the allostatic response of pancreatic beta cells to synthesise and secrete enough insulin to compensate for insulin resistance. The endocrine pancreas is a plastic tissue able to expand or regress in response to the requirements imposed by physiological and pathophysiological states associated to insulin resistance such as pregnancy, obesity or ageing, but the mechanisms mediating beta cell mass expansion in these scenarios are not well defined. We have recently shown that ob/ob mice with genetic ablation of PPARγ2, a mouse model known as the POKO mouse failed to expand its beta cell mass. This phenotype contrasted with the appropriate expansion of the beta cell mass observed in their obese littermate ob/ob mice. Thus, comparison of these models islets particularly at early ages could provide some new insights on early PPARγ dependent transcriptional responses involved in the process of beta cell mass expansion Results Here we have investigated PPARγ dependent transcriptional responses occurring during the early stages of beta cell adaptation to insulin resistance in wild type, ob/ob, PPARγ2 KO and POKO mice. We have identified genes known to regulate both the rate of proliferation and the survival signals of beta cells. Moreover we have also identified new pathways induced in ob/ob islets that remained unchanged in POKO islets, suggesting an important role for PPARγ in maintenance/activation of mechanisms essential for the continued function of the beta cell. Conclusions Our data suggest that the expansion of beta cell mass observed in ob/ob islets is associated with the activation of an immune response that fails to occur in POKO islets. We have also indentified other PPARγ dependent differentially regulated pathways including cholesterol biosynthesis, apoptosis through TGF-β signaling and decreased oxidative phosphorylation.

MuSC is involved in regulating axonal fasciculation of mouse primary vestibular afferents.

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Kawauchi, Daisuke; Kobayashi, Hiroaki; Sekine-Aizawa, Yoko; Fujita, Shinobu C; Murakami, Fujio

2003-10-01

Regulation of axonal fasciculation plays an important role in the precise patterning of neural circuits. Selective fasciculation contributes to the sorting of different types of axons and prevents the misrouting of axons. However, axons must defasciculate once they reach the target area. To study the regulation of fasciculation, we focused on the primary vestibulo-cerebellar afferents (PVAs), which show a dramatic change from fasciculated axon bundles to defasciculated individual axons at their target region, the cerebellar primordium. To understand how fasciculation and defasciculation are regulated in this system, we investigated the roles of murine SC1-related protein (MuSC), a molecule belonging to the immunoglobulin superfamily. We show: (i) by comparing 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (Dil) labelling and anti-MuSC immunohistochemistry, that downregulation of MuSC in PVAs during development is concomitant with the defasciculation of PVA axons; (ii) in a binding assay with cells expressing MuSC, that MuSC has cell-adhesive activity via a homophilic binding mechanism, and this activity is increased by multimerization; and (iii) that MuSC also displays neurite outgrowth-promoting activity in vestibular ganglion cultures. These findings suggest that MuSC is involved in axonal fasciculation and its downregulation may help to initiate the defasciculation of PVAs.

Possible Roles of CC- and CXC-Chemokines in Regulating Bovine Endometrial Function during Early Pregnancy

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Ryosuke Sakumoto

2017-03-01

Full Text Available The aim of the present study was to determine the possible roles of chemokines in regulating bovine endometrial function during early pregnancy. The expression of six chemokines, including CCL2, CCL8, CCL11, CCL14, CCL16, and CXCL10, was higher in the endometrium at 15 and 18 days of pregnancy than at the same days in non-pregnant animals. Immunohistochemical staining showed that chemokine receptors (CCR1, CCR2, CCR3, and CXCR3 were expressed in the epithelial cells and glandular epithelial cells of the bovine endometrium as well as in the fetal trophoblast obtained from a cow on day 18 of pregnancy. The addition of interferon-τ (IFNT to an endometrial tissue culture system increased CCL8 and CXCL10 expression in the tissues, but did not affect CCL2, CCL11, and CCL16 expression. CCL14 expression by these tissues was inhibited by IFNT. CCL16, but not other chemokines, clearly stimulated interferon-stimulated gene 15 (ISG15 and myxovirus-resistance gene 1 (MX1 expression in these tissues. Cyclooxygenase 2 (COX2 expression decreased after stimulation with CCL8 and CCL14, and oxytocin receptor (OTR expression was decreased by CCL2, CCL8, CCL14, and CXCL10. Collectively, the expression of chemokine genes is increased in the endometrium during early pregnancy. These genes may contribute to the regulation of endometrial function by inhibiting COX2 and OTR expression, subsequently decreasing prostaglandin production and preventing luteolysis in cows.

Neuroligin-1 induces neurite outgrowth through interaction with neurexin-1ß and activation of fibroblast growth factor receptor-1

DEFF Research Database (Denmark)

Gjørlund, Michelle D; Nielsen, Janne; Pankratova, Stanislava

2012-01-01

Neurexin-1 (NRXN1) and neuroligin-1 (NLGN1) are synaptic cell adhesion molecules that connect pre- and postsynaptic neurons at synapses and mediate signaling across the synapse, which modulates synaptic activity and determines the properties of neuronal networks. Defects in the genes encoding NLGN1...... have been linked to cognitive diseases such as autism. The roles of both NRXN1 and NLGN1 during synaptogenesis have been studied extensively, but little is known about the role of these molecules in neuritogenesis, which eventually results in neuronal circuitry formation. The present study investigated...... the neuritogenic effect of NLGN1 in cultures of hippocampal neurons. Our results show that NLGN1, both in soluble and membrane-bound forms, induces neurite outgrowth that depends on the interaction with NRXN1ß and on activation of fibroblast growth factor receptor-1. In addition, we demonstrate that a synthetic...

Extracellular signal-regulated kinase activation is required for consolidation and reconsolidation of memory at an early stage of ontogenesis.

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Languille, Solène; Davis, Sabrina; Richer, Paulette; Alcacer, Cristina; Laroche, Serge; Hars, Bernard

2009-11-01

The ability to form long-term memories exists very early during ontogeny; however, the properties of early memory processes, brain structures involved and underlying cellular mechanisms are poorly defined. Here, we examine the role of extracellular signal-regulated kinase (ERK), a member of the mitogen-activated protein kinase/ERK signaling cascade, which is crucial for adult memory, in the consolidation and reconsolidation of an early memory using a conditioned taste aversion paradigm in 3-day-old rat pups. We show that intraperitoneal injection of SL327, the upstream mitogen-activated protein kinase kinase inhibitor, impairs both consolidation and reconsolidation of early memory, leaving short-term memory after acquisition and after reactivation intact. The amnesic effect of SL327 diminishes with increasing delays after acquisition and reactivation. Biochemical analyses revealed ERK hyperphosphorylation in the amygdala but not the hippocampus following acquisition, suggesting functional activation of the amygdala as early as post-natal day 3, although there was no clear evidence for amygdalar ERK activation after reactivation. These results indicate that, despite an immature brain, the basic properties of memory and at least some of the molecular mechanisms and brain structures implicated in aversion memory share a number of similarities with the adult and emerge very early during ontogeny.

Auto-inhibitory regulation of angiotensin II functionality in hamster aorta during the early phases of dyslipidemia.

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Pereira, Priscila Cristina; Pernomian, Larissa; Côco, Hariane; Gomes, Mayara Santos; Franco, João José; Marchi, Kátia Colombo; Hipólito, Ulisses Vilela; Uyemura, Sergio Akira; Tirapelli, Carlos Renato; de Oliveira, Ana Maria

2016-06-15

Emerging data point the crosstalk between dyslipidemia and renin-angiotensin system (RAS). Advanced dyslipidemia is described to induce RAS activation in the vasculature. However, the interplay between early dyslipidemia and the RAS remains unexplored. Knowing that hamsters and humans have a similar lipid profile, we investigated the effects of early and advanced dyslipidemia on angiotensin II-induced contraction. Cumulative concentration-response curves for angiotensin II (1.0pmol/l to 1.0µmol/l) were obtained in the hamster thoracic aorta. We also investigated the modulatory action of NAD(P)H oxidase on angiotensin II-induced contraction using ML171 (Nox-1 inhibitor, 0.5µmol/l) and VAS2870 (Nox-4 inhibitor, 5µmol/l). Early dyslipidemia was detected in hamsters treated with a cholesterol-rich diet for 15 days. Early dyslipidemia decreased the contraction induced by angiotensin II and the concentration of Nox-4-derived hydrogen peroxide. Advanced dyslipidemia, observed in hamsters treated with cholesterol-rich diet for 30 days, restored the contractile response induced by angiotensin II by compensatory mechanism that involves Nox-4-mediated oxidative stress. The hyporresponsiveness to angiotensin II may be an auto-inhibitory regulation of the angiotensinergic function during early dyslipidemia in an attempt to reduce the effects of the upregulation of the vascular RAS during the advanced stages of atherogenesis. The recovery of vascular angiotensin II functionality during the advanced phases of dyslipidemia is the result of the upregulation of redox-pro-inflammatory pathway that might be most likely involved in atherogenesis progression rather than in the recovery of vascular function. Taken together, our findings show the early phase of dyslipidemia may be the most favorable moment for effective atheroprotective therapeutic interventions. Copyright © 2016 Elsevier B.V. All rights reserved.

Early growth response-1 negative feedback regulates skeletal muscle postprandial insulin sensitivity via activating Ptp1b transcription.

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Wu, Jing; Tao, Wei-Wei; Chong, Dan-Yang; Lai, Shan-Shan; Wang, Chuang; Liu, Qi; Zhang, Tong-Yu; Xue, Bin; Li, Chao-Jun

2018-03-15

Postprandial insulin desensitization plays a critical role in maintaining whole-body glucose homeostasis by avoiding the excessive absorption of blood glucose; however, the detailed mechanisms that underlie how the major player, skeletal muscle, desensitizes insulin action remain to be elucidated. Herein, we report that early growth response gene-1 ( Egr-1) is activated by insulin in skeletal muscle and provides feedback inhibition that regulates insulin sensitivity after a meal. The inhibition of the transcriptional activity of Egr-1 enhanced the phosphorylation of the insulin receptor (InsR) and Akt, thus increasing glucose uptake in L6 myotubes after insulin stimulation, whereas overexpression of Egr-1 decreased insulin sensitivity. Furthermore, deletion of Egr-1 in the skeletal muscle improved systemic insulin sensitivity and glucose tolerance, which resulted in lower blood glucose levels after refeeding. Mechanistic analysis demonstrated that EGR-1 inhibited InsR phosphorylation and glucose uptake in skeletal muscle by binding to the proximal promoter region of protein tyrosine phosphatase-1B (PTP1B) and directly activating transcription. PTP1B knockdown largely restored insulin sensitivity and enhanced glucose uptake, even under conditions of EGR-1 overexpression. Our results indicate that EGR-1/PTP1B signaling negatively regulates postprandial insulin sensitivity and suggest a potential therapeutic target for the prevention and treatment of excessive glucose absorption.-Wu, J., Tao, W.-W., Chong, D.-Y., Lai, S.-S., Wang, C., Liu, Q., Zhang, T.-Y., Xue, B., Li, C.-J. Early growth response-1 negative feedback regulates skeletal muscle postprandial insulin sensitivity via activating Ptp1b transcription.

Diffusion Tensor Imaging Tractography in Pure Neuritic Leprosy: First Experience Report and Review of the Literature

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Michele R. Colonna

2016-01-01

Full Text Available Five years after both right ulnar and median nerve decompression for paraesthesias and palsy, a patient, coming from Nigeria but living in Italy, came to our unit claiming to have persistent pain and combined median and ulnar palsy. Under suspicion of leprosy, skin and left sural nerve biopsy were performed. Skin tests were negative, but Schwann cells resulted as positive for acid-fast bacilli (AFB, leading to the diagnosis of Pure Neuritic Leprosy (PNL. The patient was given PB multidrug therapy and recovered from pain in two months. After nine months both High Resolution Ultrasonography (HRUS and Magnetic Resonance Imaging (MRI were performed, revealing thickening of the nerves. Since demyelination is common in PNL, the Authors started to use Diffusion Tensor Imaging Tractography (DTIT to get better morphological and functional data about myelination than does the traditional imaging. DTIT proved successful in showing myelin discontinuity, reorganization, and myelination, and the Authors suggest that it can give more information about the evolution of the disease, as well as further indications for surgery (nerve decompression, nerve transfers, and babysitting for distal effector protection, and should be added to traditional imaging tools in leprosy.

Longitudinal Relations between Beliefs Supporting Aggression,Anger Regulation, and Dating Aggression among Early Adolescents.

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Sullivan, Terri N; Garthe, Rachel C; Goncy, Elizabeth A; Carlson, Megan M; Behrhorst, Kathryn L

2017-05-01

Dating aggression occurs frequently in early to mid-adolescence and has negative repercussions for psychosocial adjustment and physical health. The patterns of behavior learned during this developmental timeframe may persist in future dating relationships, underscoring the need to identify risk factors for this outcome. The current study examined longitudinal relations between beliefs supporting aggression, anger regulation, and dating aggression. Participants were 176 middle school students in sixth, seventh, and eighth grade (50 % female; 82 % African American). No direct effects were found between beliefs supporting reactive or proactive aggression and dating aggression. Beliefs supporting reactive aggression predicted increased rates of anger dysregulation, and beliefs supporting proactive aggression led to subsequent increases in anger inhibition. Anger dysregulation and inhibition were associated with higher frequencies of dating aggression. An indirect effect was found for the relation between beliefs supporting reactive aggression and dating aggression via anger dysregulation. Another indirect effect emerged for the relation between beliefs supporting proactive aggression and dating aggression through anger inhibition. The study's findings suggested that beliefs supporting proactive and reactive aggression were differentially related to emotion regulation processes, and identified anger dysregulation and inhibition as risk factors for dating aggression among adolescents.

PDGF-regulated rab4-dependent recycling of alphavbeta3 integrin from early endosomes is necessary for cell adhesion and spreading.

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Roberts, M; Barry, S; Woods, A; van der Sluijs, P; Norman, J

2001-09-18

It has been postulated that the regulation of integrin vesicular traffic facilitates cell migration by internalizing integrins at the rear of the cell and transporting them forward within vesicles for exocytosis at the leading edge to form new contacts with the extracellular matrix. The rab family of GTPases control key targeting events in the endo/exocytic pathway; therefore, these GTPases may be involved in the regulation of cell-matrix contact assembly. The endo/exocytic cycle of alphavbeta3 and alpha5beta1 integrins was studied using mouse 3T3 fibroblast cell lines. In serum-starved cells, internalized integrins were transported through rab4-positive, early endosomes and arrived at the rab11-positive, perinuclear recycling compartment approximately 30 min after endocytosis. From the recycling compartment, integrins were recycled to the plasma membrane in a rab11-dependent fashion. Following treatment with PDGF, alphavbeta3 integrin, but not alpha5beta1, was rapidly recycled directly back to the plasma membrane from the early endosomes via a rab4-dependent mechanism without the involvement of rab11. This rapid recycling pathway directed alphavbeta3 to numerous small puncta distributed evenly across the dorsal surface of the cell, and the integrin only became localized into focal complexes at later times following PDGF addition. Interestingly, inhibition of PDGF-stimulated alphavbeta3 recycling using dominant-negative rab4 mutants compromised cell adhesion and spreading on vitronectin (a ligand for alphavbeta3), but adhesion to fibronectin (a ligand for alpha5beta1 and alphavbeta3) was unchanged. We propose that growth factor-regulated, rab4-dependent recycling of alphavbeta3 integrin from early endosomes to the plasma membrane is a critical upstream event in the assembly of cell-matrix contacts.

Regulation of early and delayed radiation responses in rat small intestine by capsaicin-sensitive nerves

International Nuclear Information System (INIS)

Wang Junru; Zheng Huaien; Kulkarni, Ashwini; Ou Xuemei; Hauer-Jensen, Martin

2006-01-01

Purpose: Mast cells protect against the early manifestations of intestinal radiation toxicity, but promote chronic intestinal wall fibrosis. Intestinal sensory nerves are closely associated with mast cells, both anatomically and functionally, and serve an important role in the regulation of mucosal homeostasis. This study examined the effect of sensory nerve ablation on the intestinal radiation response in an established rat model. Methods and Materials: Rats underwent sensory nerve ablation with capsaicin or sham ablation. Two weeks later, a localized segment of ileum was X-irradiated or sham irradiated. Structural, cellular, and molecular changes were examined 2 weeks (early injury) and 26 weeks (chronic injury) after irradiation. The mast cell dependence of the effect of sensory nerve ablation on intestinal radiation injury was assessed using c-kit mutant (Ws/Ws) mast cell-deficient rats. Results: Capsaicin treatment caused a baseline reduction in mucosal mast cell density, crypt cell proliferation, and expression of substance P and calcitonin gene-related peptide, two neuropeptides released by sensory neurons. Sensory nerve ablation strikingly exacerbated early intestinal radiation toxicity (loss of mucosal surface area, inflammation, intestinal wall thickening), but attenuated the development of chronic intestinal radiation fibrosis (collagen I accumulation and transforming growth factor β immunoreactivity). In mast cell-deficient rats, capsaicin treatment exacerbated postradiation epithelial injury (loss of mucosal surface area), but none of the other aspects of radiation injury were affected by capsaicin treatment. Conclusions: Ablation of capsaicin-sensitive enteric neurons exacerbates early intestinal radiation toxicity, but attenuates development of chronic fibroproliferative changes. The effect of capsaicin treatment on the intestinal radiation response is partly mast cell dependent

Selective phosphorylation during early macrophage differentiation

KAUST Repository

Zhang, Huoming

2015-08-26

The differentiation of macrophages from monocytes is a tightly controlled and complex biological process. Although numerous studies have been conducted using biochemical approaches or global gene/gene profiling, the mechanisms of the early stages of differentiation remain unclear. Here we used SILAC-based quantitative proteomics approach to perform temporal phosphoproteome profiling of early macrophage differentiation. We identified a large set of phosphoproteins and grouped them as PMA-regulated and non-regulated phosphoproteins in the early stages of differentiation. Further analysis of the PMA-regulated phosphoproteins revealed that transcriptional suppression, cytoskeletal reorganization and cell adhesion were among the most significantly activated pathways. Some key involved regulators of these pathways are mTOR, MYB, STAT1 and CTNNB. Moreover, we were able to classify the roles and activities of several transcriptional factors during different differentiation stages and found that E2F is likely to be an important regulator during the relatively late stages of differentiation. This study provides the first comprehensive picture of the dynamic phosphoproteome during myeloid cells differentiation, and identifies potential molecular targets in leukemic cells.

Chemical constituents from Hericium erinaceus and their ability to stimulate NGF-mediated neurite outgrowth on PC12 cells.

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Zhang, Cheng-Chen; Yin, Xia; Cao, Chen-Yu; Wei, Jing; Zhang, Qiang; Gao, Jin-Ming

2015-11-15

One new meroterpenoid, named hericenone K (11), along with 10 known compounds (1-10), ergosterol peroxide (1), cerevisterol (2), 3β,5α,9α-trihydroxy-ergosta-7,22-dien-6-one (3), inoterpene A (4), astradoric acid C (5), betulin (6), oleanolic acid (7), ursolic acid (8), hemisceramide (9), and 3,4-dihydro-5-methoxy-2-methyl-2-(4'-methyl-2'-oxo-3'-pentenyl)-9(7H)-oxo-2H-furo[3,4-h]benzopyran (10), was isolated from the fruiting bodies of the mushroom Hericium erinaceus. Their structures were characterized on the basis of spectroscopic methods, as well as through comparison with previously reported data. Compounds 3-6, 8, and 9 were isolated from Hericium species for the first time. Compounds 10 and 11 was suggested to be racemic by the CD spectrum data and specific rotations, which ware resolved by chiral HPLC into respective enantiomers. Compounds 1-3, (±)-10, (-)-10 and (+)-10 in the presence of NGF (20 ng/mL) exerted a significant increase in neurite-bearing cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

Increased cystic fibrosis transmembrane conductance regulators expression and decreased epithelial sodium channel alpha subunits expression in early abortion: findings from a mouse model and clinical cases of abortion.

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Min Zhou

Full Text Available The status of the maternal endometrium is vital in regulating humoral homeostasis and for ensuring embryo implantation. Cystic fibrosis transmembrane conductance regulators (CFTR and epithelial sodium channel alpha subunits (ENaC-α play an important role in female reproduction by maintaining humoral and cell homeostasis. However, it is not clear whether the expression levels of CFTR and ENaC-α in the decidual component during early pregnancy are related with early miscarriage. CBA×DBA/2 mouse mating has been widely accepted as a classical model of early miscarriage. The abortion rate associated with this mating was 33.33% in our study. The decidua of abortion-prone CBA female mice (DBA/2 mated had higher CFTR mRNA and protein expression and lower ENaC-α mRNA and protein expression, compared to normal pregnant CBA mice (BLAB/C mated. Furthermore, increased CFTR expression and decreased ENaC-α expression were observed in the uterine tissue from women with early miscarriage, as compared to those with successful pregnancy. In conclusion, increased CFTR expression and decreased ENaC-α expression in the decidua of early abortion may relate with failure of early pregnancy.

Cerebral amyloid-beta protein accumulation with aging in cotton-top tamarins: a model of early Alzheimer's disease?

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Lemere, Cynthia A; Oh, Jiwon; Stanish, Heather A; Peng, Ying; Pepivani, Imelda; Fagan, Anne M; Yamaguchi, Haruyasu; Westmoreland, Susan V; Mansfield, Keith G

2008-04-01

Alzheimer's disease (AD) is the most common progressive form of dementia in the elderly. Two major neuropathological hallmarks of AD include cerebral deposition of amyloid-beta protein (Abeta) into plaques and blood vessels, and the presence of neurofibrillary tangles in brain. In addition, activated microglia and reactive astrocytes are often associated with plaques and tangles. Numerous other proteins are associated with plaques in human AD brain, including Apo E and ubiquitin. The amyloid precursor protein and its shorter fragment, Abeta, are homologous between humans and non-human primates. Cerebral Abeta deposition has been reported previously for rhesus monkeys, vervets, squirrel monkeys, marmosets, lemurs, cynomologous monkeys, chimpanzees, and orangutans. Here we report, for the first time, age-related neuropathological changes in cotton-top tamarins (CTT, Saguinus oedipus), an endangered non-human primate native to the rainforests of Colombia and Costa Rica. Typical lifespan is 13-14 years of age in the wild and 15-20+ years in captivity. We performed detailed immunohistochemical analyses of Abeta deposition and associated pathogenesis in archived brain sections from 36 tamarins ranging in age from 6-21 years. Abeta plaque deposition was observed in 16 of the 20 oldest tamarins (>12 years). Plaques contained mainly Abeta42, and in the oldest animals, were associated with reactive astrocytes, activated microglia, Apo E, and ubiquitin-positive dystrophic neurites, similar to human plaques. Vascular Abeta was detected in 14 of the 20 aged tamarins; Abeta42 preceded Abeta40 deposition. Phospho-tau labeled dystrophic neurites and tangles, typically present in human AD, were absent in the tamarins. In conclusion, tamarins may represent a model of early AD pathology.

Early regulation of axolotl limb regeneration.

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Makanae, Aki; Satoh, Akira

2012-10-01

Amphibian limb regeneration has been studied for a long time. In amphibian limb regeneration, an undifferentiated blastema is formed around the region damaged by amputation. The induction process of blastema formation has remained largely unknown because it is difficult to study the induction of limb regeneration. The recently developed accessory limb model (ALM) allows the investigation of limb induction and reveals early events of amphibian limb regeneration. The interaction between nerves and wound epidermis/epithelium is an important aspect of limb regeneration. During early limb regeneration, neurotrophic factors act on wound epithelium, leading to development of a functional epidermis/epithelium called the apical epithelial cap (AEC). AEC and nerves create a specific environment that inhibits wound healing and induces regeneration through blastema formation. It is suggested that FGF-signaling and MMP activities participate in creating a regenerative environment. To understand why urodele amphibians can create such a regenerative environment and humans cannot, it is necessary to identify the similarities and differences between regenerative and nonregenerative animals. Here we focus on ALM to consider limb regeneration from a new perspective and we also reported that focal adhesion kinase (FAK)-Src signaling controlled fibroblasts migration in axolotl limb regeneration. Copyright © 2012 Wiley Periodicals, Inc.

Risk factors for alcoholism in the Oklahoma Family Health Patterns project: impact of early life adversity and family history on affect regulation and personality.

Science.gov (United States)

Sorocco, Kristen H; Carnes, Nathan C; Cohoon, Andrew J; Vincent, Andrea S; Lovallo, William R

2015-05-01

This study examined the impact of early lifetime adversity (ELA) on affect regulation and personality in persons with family history (FH+) and without (FH-) a family history of alcoholism. We examined the impact of early life adversity in healthy young adults, 18-30 years of age enrolled in a long-term study on risk for alcohol and other substance abuse. ELA was assessed by a composite score of low socioeconomic status and personal experience of physical or sexual abuse and/or separation from parents before age 16, resulting in a score of 0, 1-2, or >3 adverse events. Unstable affect regulation and personality variables were obtained via self-report measures. Higher ELA scores were seen in FH+ (χ(2)=109.2, paffect regulation, negative moods, and have risky drinking and drug abuse tendencies independent of ELA level. ELA predicts reduced stress reactivity and poorer cognitive control over impulsive behaviors as shown elsewhere. The present work shows that FH+ have poor mood regulation and antisocial characteristics. The greater prevalence of ELA in FH+ persons indicates that life experience and FH+ work in tandem to result in risky patterns of alcohol and drug experimentation to elevate risk for alcoholism. Further studies of genetic and environmental contributions to alcoholism are called for. Published by Elsevier Ireland Ltd.

KCNK10, a Tandem Pore Domain Potassium Channel, Is a Regulator of Mitotic Clonal Expansion during the Early Stage of Adipocyte Differentiation

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Makoto Nishizuka

2014-12-01

Full Text Available KCNK10, a member of tandem pore domain potassium channel family, gives rise to leak K+ currents. It plays important roles in stabilizing the negative resting membrane potential and in counterbalancing depolarization. We previously demonstrated that kcnk10 expression is quickly elevated during the early stage of adipogenesis of 3T3-L1 cells and that reduction of kcnk10 expression inhibits adipocyte differentiation. However, the molecular mechanism of KCNK10 in adipocyte differentiation remains unclear. Here we revealed that kcnk10 is induced by 3-isobutyl-1-methylxanthine, a cyclic nucleotide phosphodiesterase inhibitor and a potent inducer of adipogenesis, during the early stage of adipocyte differentiation. We also demonstrated that KCNK10 functions as a positive regulator of mitotic clonal expansion (MCE, a necessary process for terminal differentiation. The reduction of kcnk10 expression repressed the expression levels of CCAAT/enhancer-binding protein β (C/EBPβ and C/EBPδ as well as the phosphorylation level of Akt during the early phase of adipogenesis. In addition, knockdown of kcnk10 expression suppressed insulin-induced Akt phosphorylation. These results indicate that KCNK10 contributes to the regulation of MCE through the control of C/EBPβ and C/EBPδ expression and insulin signaling.

Are trajectories of self-regulation abilities from ages 2-3 to 6-7 associated with academic achievement in the early school years?

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Sawyer, A C P; Chittleborough, C R; Mittinty, M N; Miller-Lewis, L R; Sawyer, M G; Sullivan, T; Lynch, J W

2015-09-01

The aim of this study was to estimate the association between two key aspects of self-regulation, 'task attentiveness' and 'emotional regulation' assessed from ages 2-3 to 6-7 years, and academic achievement when children were aged 6-7 years. Participants (n = 3410) were children in the Longitudinal Study of Australian Children. Parents rated children's task attentiveness and emotional regulation abilities when children were aged 2-3, 4-5 and 6-7. Academic achievement was assessed using the Academic Rating Scale completed by teachers. Linear regression models were used to estimate the association between developmental trajectories (i.e. rate of change per year) of task attentiveness and emotional regulation, and academic achievement at 6-7 years. Improvements in task attentiveness between 2-3 and 6-7 years, adjusted for baseline levels of task attentiveness, child and family confounders, and children's receptive vocabulary and non-verbal reasoning skills at age 6-7 were associated with greater teacher-rated literacy [B = 0.05, 95% confidence interval (CI) = 0.04-0.06] and maths achievement (B = 0.04, 95% CI = 0.03-0.06) at 6-7 years. Improvements in emotional regulation, adjusting for baseline levels and covariates, were also associated with better teacher-rated literacy (B = 0.02, 95% CI = 0.01-0.04) but not with maths achievement (B = 0.01, 95% CI = -0.01-0.02) at 6-7 years. For literacy, improvements in task attentiveness had a stronger association with achievement at 6-7 years than improvements in emotional regulation. Our study shows that improved trajectories of task attentiveness from ages 2-3 to 6-7 years are associated with improved literacy and maths achievement during the early school years. Trajectories of improving emotional regulation showed smaller effects on academic outcomes. Results suggest that interventions that improve task attentiveness when children are aged 2-3 to 6-7 years have the potential to improve literacy and maths achievement during

Comparison of neurotrophin and repellent sensitivities of early embryonic geniculate and trigeminal axons

NARCIS (Netherlands)

Rochlin, M William; O'Connor, R.; Giger, Roman J; Verhaagen, J; Farbman, A I

2000-01-01

Geniculate (gustatory) and trigeminal (somatosensory) afferents take different routes to the tongue during rat embryonic development. To learn more about the mechanisms controlling neurite outgrowth and axon guidance, we are studying the roles of diffusible factors. We previously profiled the in

Inhibition of Rho kinase regulates specification of early differentiation events in P19 embryonal carcinoma stem cells.

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Roman J Krawetz

Full Text Available The Rho kinase pathway plays a key role in many early cell/tissue determination events that take place in embryogenesis. Rho and its downstream effector Rho kinase (ROCK play pivotal roles in cell migration, apoptosis (membrane blebbing, cell proliferation/cell cycle, cell-cell adhesion and gene regulation. We and others have previously demonstrated that inhibition of ROCK blocks endoderm differentiation in embryonal carcinoma stem cells, however, the effect of ROCK inhibition on mesoderm and ectoderm specification has not been fully examined. In this study, the role of ROCK within the specification and differentiation of all three germ layers was examined.P19 cells were treated with the specific ROCK inhibitor Y-27623, and increase in differentiation efficiency into neuro-ectodermal and mesodermal lineages was observed. However, as expected a dramatic decrease in early endodermal markers was observed when ROCK was inhibited. Interestingly, within these ROCK-inhibited RA treated cultures, increased levels of mesodermal or ectodermal markers were not observed, instead it was found that the pluripotent markers SSEA-1 and Oct-4 remained up-regulated similar to that seen in undifferentiated cultures. Using standard and widely accepted methods for reproducible P19 differentiation into all three germ layers, an enhancement of mesoderm and ectoderm differentiation with a concurrent loss of endoderm lineage specification was observed with Y-27632 treatment. Evidence would suggest that this effect is in part mediated through TGF-β and SMAD signaling as ROCK-inhibited cells displayed aberrant SMAD activation and did not return to a 'ground' state after the inhibition had been removed.Given this data and the fact that only a partial rescue of normal differentiation capacity occurred when ROCK inhibition was alleviated, the effect of ROCK inhibition on the differentiation capacity of pluripotent cell populations should be further examined to elucidate the

Zinc Promotes Adipose-Derived Mesenchymal Stem Cell Proliferation and Differentiation towards a Neuronal Fate.

Science.gov (United States)

Moon, Mi-Young; Kim, Hyun Jung; Choi, Bo Young; Sohn, Min; Chung, Tae Nyoung; Suh, Sang Won

2018-01-01

Zinc is an essential element required for cell division, migration, and proliferation. Under zinc-deficient conditions, proliferation and differentiation of neural progenitors are significantly impaired. Adipose-derived mesenchymal stem cells (AD-MSCs) are multipotent stem cells that can differentiate into neurons. The aim of this study was to evaluate the effect of zinc on AD-MSC proliferation and differentiation. We initially examined the effect of zinc on stem cell proliferation at the undifferentiated stage. AD-MSCs showed high proliferation rates on day 6 in 30  μ M and 100  μ M of ZnCl 2 . Zinc chelation inhibited AD-MSC proliferation via downregulation of ERK1/2 activity. We then assessed whether zinc was involved in cell migration and neurite outgrowth during differentiation. After three days of neuronal differentiation, TUJ-1-positive cells were observed, implying that AD-MSCs had differentiated into early neuron or neuron-like cells. Neurite outgrowth was increased in the zinc-treated group, while the CaEDTA-treated group showed diminished, shrunken neurites. Furthermore, we showed that zinc promoted neurite outgrowth via the inactivation of RhoA and led to the induction of neuronal gene expression (MAP2 and nestin) in differentiated stem cells. Taken together, zinc promoted AD-MSC proliferation and affected neuronal differentiation, mainly by increasing neurite outgrowth.

Zinc Promotes Adipose-Derived Mesenchymal Stem Cell Proliferation and Differentiation towards a Neuronal Fate

Directory of Open Access Journals (Sweden)

Mi-Young Moon

2018-01-01

Full Text Available Zinc is an essential element required for cell division, migration, and proliferation. Under zinc-deficient conditions, proliferation and differentiation of neural progenitors are significantly impaired. Adipose-derived mesenchymal stem cells (AD-MSCs are multipotent stem cells that can differentiate into neurons. The aim of this study was to evaluate the effect of zinc on AD-MSC proliferation and differentiation. We initially examined the effect of zinc on stem cell proliferation at the undifferentiated stage. AD-MSCs showed high proliferation rates on day 6 in 30 μM and 100 μM of ZnCl2. Zinc chelation inhibited AD-MSC proliferation via downregulation of ERK1/2 activity. We then assessed whether zinc was involved in cell migration and neurite outgrowth during differentiation. After three days of neuronal differentiation, TUJ-1-positive cells were observed, implying that AD-MSCs had differentiated into early neuron or neuron-like cells. Neurite outgrowth was increased in the zinc-treated group, while the CaEDTA-treated group showed diminished, shrunken neurites. Furthermore, we showed that zinc promoted neurite outgrowth via the inactivation of RhoA and led to the induction of neuronal gene expression (MAP2 and nestin in differentiated stem cells. Taken together, zinc promoted AD-MSC proliferation and affected neuronal differentiation, mainly by increasing neurite outgrowth.

Myocardial Tbx20 regulates early atrioventricular canal formation and endocardial epithelial-mesenchymal transition via Bmp2.

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Cai, Xiaoqiang; Nomura-Kitabayashi, Aya; Cai, Weibin; Yan, Jianyun; Christoffels, Vincent M; Cai, Chen-Leng

2011-12-15

During early embryogenesis, the formation of the cardiac atrioventricular canal (AVC) facilitates the transition of the heart from a linear tube into a chambered organ. However, the genetic pathways underlying this developmental process are poorly understood. The T-box transcription factor Tbx20 is expressed predominantly in the AVC of early heart tube. It was shown that Tbx20 activates Nmyc1 and suppresses Tbx2 expression to promote proliferation and specification of the atrial and ventricular chambers, yet it is not known if Tbx20 is involved in early AVC development. Here, we report that mice lacking Tbx20 in the AVC myocardium fail to form the AVC constriction, and the endocardial epithelial-mesenchymal transition (EMT) is severely perturbed. Tbx20 maintains expression of a variety of genes, including Bmp2, Tbx3 and Hand1 in the AVC myocardium. Intriguingly, we found Bmp2 downstream genes involved in the EMT initiation are also downregulated. In addition, re-expression of Bmp2 in the AVC myocardium substantially rescues the EMT defects resulting from the lack of Tbx20, suggesting Bmp2 is one of the key downstream targets of Tbx20 in AVC development. Our data support a complex signaling network with Tbx20 suppressing Tbx2 in the AVC myocardium but also indirectly promoting Tbx2 expression through Bmp2. The spatiotemporal expression of Tbx2 in the AVC appears to be balanced between these two opposing signals. Overall, our study provides genetic evidence that Tbx20 has essential roles in regulating AVC development that coordinate early cardiac chamber formation. Copyright © 2011 Elsevier Inc. All rights reserved.

Common pathogenic effects of missense mutations in the P-type ATPase ATP13A2 (PARK9) associated with early-onset parkinsonism.

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Podhajska, Agata; Musso, Alessandra; Trancikova, Alzbeta; Stafa, Klodjan; Moser, Roger; Sonnay, Sarah; Glauser, Liliane; Moore, Darren J

2012-01-01

Mutations in the ATP13A2 gene (PARK9) cause autosomal recessive, juvenile-onset Kufor-Rakeb syndrome (KRS), a neurodegenerative disease characterized by parkinsonism. KRS mutations produce truncated forms of ATP13A2 with impaired protein stability resulting in a loss-of-function. Recently, homozygous and heterozygous missense mutations in ATP13A2 have been identified in subjects with early-onset parkinsonism. The mechanism(s) by which missense mutations potentially cause parkinsonism are not understood at present. Here, we demonstrate that homozygous F182L, G504R and G877R missense mutations commonly impair the protein stability of ATP13A2 leading to its enhanced degradation by the proteasome. ATP13A2 normally localizes to endosomal and lysosomal membranes in neurons and the F182L and G504R mutations disrupt this vesicular localization and promote the mislocalization of ATP13A2 to the endoplasmic reticulum. Heterozygous T12M, G533R and A746T mutations do not obviously alter protein stability or subcellular localization but instead impair the ATPase activity of microsomal ATP13A2 whereas homozygous missense mutations disrupt the microsomal localization of ATP13A2. The overexpression of ATP13A2 missense mutants in SH-SY5Y neural cells does not compromise cellular viability suggesting that these mutant proteins lack intrinsic toxicity. However, the overexpression of wild-type ATP13A2 may impair neuronal integrity as it causes a trend of reduced neurite outgrowth of primary cortical neurons, whereas the majority of disease-associated missense mutations lack this ability. Finally, ATP13A2 overexpression sensitizes cortical neurons to neurite shortening induced by exposure to cadmium or nickel ions, supporting a functional interaction between ATP13A2 and heavy metals in post-mitotic neurons, whereas missense mutations influence this sensitizing effect. Collectively, our study provides support for common loss-of-function effects of homozygous and heterozygous missense

Antiangiogenic treatment diminishes renal injury and dysfunction via regulation of local AKT in early experimental diabetes.

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Bai, Xiaoyan; Li, Xiao; Tian, Jianwei; Zhou, Zhanmei

2014-01-01

In view of increased vascular endothelial growth factor-A (VEGF-A) expression and renal dysfunction in early diabetes, we designed a study to test whether VEGF-A inhibition can prevent early renal injury and dysfunction. We investigated the relationship and mechanism between VEGF-A and AKT regulation. In vitro, VEGF-A small interfering RNA (siRNA) and AKT inhibitor MK-2206 were employed to podocytes and NRK-52 cells cultured in high glucose (30 mM). In vivo, the antiangiogenic drug endostatin was administered in 12 week-old streptozotocin-induced male Sprague Dawley rats. The levels of VEGF-A, AKT, phosphorylated Ser⁴⁷³-AKT, phosphorylated Thr³⁰⁸-AKT, nephrin, angiotensin II (Ang II), angiotensin type II receptor 1 (ATR1) were examined using quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR), Western blot analysis and immunohistochemistry. Interactions between phosphorylated Thr³⁰⁸-AKT and either nephrin in podocytes or Ang II in renal tubules were studied, respectively, using confocal immunofluorescence microscopy and immunoprecipitation. Silencing VEGF-A in podocytes upregulated phosphorylated Thr³⁰⁸-AKT and nephrin. Silencing VEGF-A in NRK-52E cells upregulated phosphorylated Thr³⁰⁸-AKT while downregulated Ang II and ATR1. MK-2206 enhanced VEGF-A expression in both podocytes and NRK-52E cells by inhibiting AKT activities. In diabetic rat kidneys, VEGF-A was upregulated and phosphorylated Thr³⁰⁸-AKT colocalized with either nephrin in podocytes or Ang II in renal tubules. With the endostatin treatment, the level of VEGF-A decreased while phosphorylated Thr³⁰⁸-AKT increased in both glomeruli and renal tubules. Treatment with endostatin upregulated nephrin in podocytes while downregulated Ang II and AT1R in renal tubules. Glomerular mesangial expansion was attenuated by the endostatin treatment, however, differences did not reach statistical significance. Endostatin ameliorated the interstitial fibrosis

Antiangiogenic treatment diminishes renal injury and dysfunction via regulation of local AKT in early experimental diabetes.

Directory of Open Access Journals (Sweden)

Xiaoyan Bai

Full Text Available In view of increased vascular endothelial growth factor-A (VEGF-A expression and renal dysfunction in early diabetes, we designed a study to test whether VEGF-A inhibition can prevent early renal injury and dysfunction. We investigated the relationship and mechanism between VEGF-A and AKT regulation. In vitro, VEGF-A small interfering RNA (siRNA and AKT inhibitor MK-2206 were employed to podocytes and NRK-52 cells cultured in high glucose (30 mM. In vivo, the antiangiogenic drug endostatin was administered in 12 week-old streptozotocin-induced male Sprague Dawley rats. The levels of VEGF-A, AKT, phosphorylated Ser⁴⁷³-AKT, phosphorylated Thr³⁰⁸-AKT, nephrin, angiotensin II (Ang II, angiotensin type II receptor 1 (ATR1 were examined using quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR, Western blot analysis and immunohistochemistry. Interactions between phosphorylated Thr³⁰⁸-AKT and either nephrin in podocytes or Ang II in renal tubules were studied, respectively, using confocal immunofluorescence microscopy and immunoprecipitation. Silencing VEGF-A in podocytes upregulated phosphorylated Thr³⁰⁸-AKT and nephrin. Silencing VEGF-A in NRK-52E cells upregulated phosphorylated Thr³⁰⁸-AKT while downregulated Ang II and ATR1. MK-2206 enhanced VEGF-A expression in both podocytes and NRK-52E cells by inhibiting AKT activities. In diabetic rat kidneys, VEGF-A was upregulated and phosphorylated Thr³⁰⁸-AKT colocalized with either nephrin in podocytes or Ang II in renal tubules. With the endostatin treatment, the level of VEGF-A decreased while phosphorylated Thr³⁰⁸-AKT increased in both glomeruli and renal tubules. Treatment with endostatin upregulated nephrin in podocytes while downregulated Ang II and AT1R in renal tubules. Glomerular mesangial expansion was attenuated by the endostatin treatment, however, differences did not reach statistical significance. Endostatin ameliorated the

Dopaminergic neuronal loss, reduced neurite complexity and autophagic abnormalities in transgenic mice expressing G2019S mutant LRRK2.

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David Ramonet

2011-04-01

Full Text Available Mutations in the leucine-rich repeat kinase 2 (LRRK2 gene cause late-onset, autosomal dominant familial Parkinson's disease (PD and also contribute to idiopathic PD. LRRK2 mutations represent the most common cause of PD with clinical and neurochemical features that are largely indistinguishable from idiopathic disease. Currently, transgenic mice expressing wild-type or disease-causing mutants of LRRK2 have failed to produce overt neurodegeneration, although abnormalities in nigrostriatal dopaminergic neurotransmission have been observed. Here, we describe the development and characterization of transgenic mice expressing human LRRK2 bearing the familial PD mutations, R1441C and G2019S. Our study demonstrates that expression of G2019S mutant LRRK2 induces the degeneration of nigrostriatal pathway dopaminergic neurons in an age-dependent manner. In addition, we observe autophagic and mitochondrial abnormalities in the brains of aged G2019S LRRK2 mice and markedly reduced neurite complexity of cultured dopaminergic neurons. These new LRRK2 transgenic mice will provide important tools for understanding the mechanism(s through which familial mutations precipitate neuronal degeneration and PD.

Selective phosphorylation during early macrophage differentiation

KAUST Repository

Zhang, Huoming; Qian, Pei-Yuan; Ravasi, Timothy

2015-01-01

-regulated phosphoproteins in the early stages of differentiation. Further analysis of the PMA-regulated phosphoproteins revealed that transcriptional suppression, cytoskeletal reorganization and cell adhesion were among the most significantly activated pathways. Some key

Lindersin B from Lindernia crustacea induces neuritogenesis by activation of tyrosine kinase A/phosphatidylinositol 3 kinase/extracellular signal-regulated kinase signaling pathway.

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Cheng, Lihong; Ye, Ying; Xiang, Lan; Osada, Hiroyuki; Qi, Jianhua

2017-01-15

Neurotrophic factors such as nerve growth factor (NGF) play important roles in nervous system. NGF is a potential therapeutic drug for treatment of neurodegenerative diseases. However, because of physicochemical property, NGF cannot pass through the blood-brain barrier (BBB). Hence, small molecules which exhibit NGF-mimic activity and can pass through the BBB are considered to be promising drug candidates for treatment of such diseases. The present study was designed to isolate NGF-mimic substance from extract of natural products, determine their structures and investigate mechanism of action of the active substance. Extract of Lindernia crustacean was partitioned between water and ethyl acetate to obtain water layer and ethyl acetate layer samples, respectively, and then evaluated their neuritogenic activity in PC12 cells. The active sample was separated by open columns, followed by HPLC purification to obtain active compound. Then, specific inhibitors were used to investigate signaling pathway of neurite outgrowth induced by the active compound. Finally, western blot analysis was performed to confirm the pathway proposed by inhibitor experiments. The ethyl acetate layer sample of extract of Lindernia crustacea exhibited significant neuritogenic activity. Two new compounds, named as linderside A and lindersin B, were isolated; their structures were elucidated by spectroscopic and chemical derivatization methods. Linderside A is a cucurbitane glycoside, whereas lindersin B is a cucurbitane triterpenoid. Each compound has an unusual isopentene unit, namely, a double bond bound to an unmodified isopropyl group at the end of cucurbitane triterpenoid side chain. Among them, lindersin B induced significant neurite outgrowth in PC12 cells, while linderside A was inactive against PC12 cells. Western blotting analysis results showed that lindersin B-induced neuritogenic activity depended on the activation of the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated

Practices for Parent Participation in Early Intervention/ Early Childhood Special Education

OpenAIRE

Acar, Serra; Akamoğlu, Yusuf

2014-01-01

The authors examined the extent to which practices for parent participation in early intervention/ early childhood special education (EI/ECSE) programs. The role of parents in the EI/ECSE is important and supported through the literature. The changing traditional family picture in the classrooms, the importance of evolving laws and regulations and recommended practices regarding parent participation are highlighted. The conceptual framework is based on the children, parents, and practitioners...

The fidelity of synaptonemal complex assembly is regulated by a signaling mechanism that controls early meiotic progression.

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Silva, Nicola; Ferrandiz, Nuria; Barroso, Consuelo; Tognetti, Silvia; Lightfoot, James; Telecan, Oana; Encheva, Vesela; Faull, Peter; Hanni, Simon; Furger, Andre; Snijders, Ambrosius P; Speck, Christian; Martinez-Perez, Enrique

2014-11-24

Proper chromosome segregation during meiosis requires the assembly of the synaptonemal complex (SC) between homologous chromosomes. However, the SC structure itself is indifferent to homology, and poorly understood mechanisms that depend on conserved HORMA-domain proteins prevent ectopic SC assembly. Although HORMA-domain proteins are thought to regulate SC assembly as intrinsic components of meiotic chromosomes, here we uncover a key role for nuclear soluble HORMA-domain protein HTP-1 in the quality control of SC assembly. We show that a mutant form of HTP-1 impaired in chromosome loading provides functionality of an HTP-1-dependent checkpoint that delays exit from homology search-competent stages until all homolog pairs are linked by the SC. Bypassing of this regulatory mechanism results in premature meiotic progression and licensing of homology-independent SC assembly. These findings identify nuclear soluble HTP-1 as a regulator of early meiotic progression, suggesting parallels with the mode of action of Mad2 in the spindle assembly checkpoint. Copyright © 2014 Elsevier Inc. All rights reserved.

Regulation of angiotensin II-induced neuromodulation by MARCKS in brain neurons.

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Lu, D; Yang, H; Lenox, R H; Raizada, M K

1998-07-13

Angiotensin II (Ang II) exerts chronic stimulatory actions on tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DbetaH), and the norepinephrine transporter (NET), in part, by influencing the transcription of their genes. These neuromodulatory actions of Ang II involve Ras-Raf-MAP kinase signal transduction pathways (Lu, D., H. Yang, and M.K. Raizada. 1997. J. Cell Biol. 135:1609-1617). In this study, we present evidence to demonstrate participation of another signaling pathway in these neuronal actions of Ang II. It involves activation of protein kinase C (PKC)beta subtype and phosphorylation and redistribution of myristoylated alanine-rich C kinase substrate (MARCKS) in neurites. Ang II caused a dramatic redistribution of MARCKS from neuronal varicosities to neurites. This was accompanied by a time-dependent stimulation of its phosphorylation, that was mediated by the angiotensin type 1 receptor subtype (AT1). Incubation of neurons with PKCbeta subtype specific antisense oligonucleotide (AON) significantly attenuated both redistribution and phosphorylation of MARCKS. Furthermore, depletion of MARCKS by MARCKS-AON treatment of neurons resulted in a significant decrease in Ang II-stimulated accumulation of TH and DbetaH immunoreactivities and [3H]NE uptake activity in synaptosomes. In contrast, mRNA levels of TH, DbetaH, and NET were not influenced by MARKS-AON treatment. MARCKS pep148-165, which contains PKC phosphorylation sites, inhibited Ang II stimulation of MARCKS phosphorylation and reduced the amount of TH, DbetaH, and [3H]NE uptake in neuronal synaptosomes. These observations demonstrate that phosphorylation of MARCKS by PKCbeta and its redistribution from varicosities to neurites is important in Ang II-induced synaptic accumulation of TH, DbetaH, and NE. They suggest that a coordinated stimulation of transcription of TH, DbetaH, and NET, mediated by Ras-Raf-MAP kinase followed by their transport mediated by PKCbeta-MARCKS pathway are key in persistent

Family Income Dynamics, Early Childhood Education and Care, and Early Child Behavior Problems in Norway

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Zachrisson, Henrik D.; Dearing, Eric

2015-01-01

The sociopolitical context of Norway includes low poverty rates and universal access to subsidized and regulated Early Childhood Education and Care (ECEC). In this context, the association between family income dynamics and changes in early child behavior problems was investigated, as well as whether high-quality ECEC buffers children from the…

Early Childhood Media Exposure and Self-Regulation: Bi-Directional Longitudinal Associations.

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Cliff, Dylan P; Howard, Steven J; Radesky, Jenny S; McNeill, Jade; Vella, Stewart A

2018-04-26

To investigate: i) prospective associations between media exposure (television viewing, computers, and electronic games) at 2 years and self-regulation at 4 and 6 years, and ii) bi-directional associations between media exposure and self-regulation at 4 and 6 years. We hypothesized that media exposure and self-regulation would display a negative prospective association and subsequent bi-directional inverse associations. Data from the nationally-representative Longitudinal Study of Australian Children (LSAC) when children were aged 2 (n=2786) and 4/6 years (n=3527) were used. Primary caregivers reported children's weekly electronic media exposure. A composite measure of self-regulation was computed from caregivers-, teacher-, and observer-report data. Associations were examined using linear regression and cross-lagged panel models, accounting for covariates. Lower television viewing and total media exposure at 2 years were associated with higher self-regulation at 4 years (both β -0.02; 95% confidence interval [CI] -0.03, -0.01). Lower self-regulation at 4 years was also significantly associated with higher television viewing (β -0.15; 95% CI -0.21, -0.08), electronic game use (β -0.05; 95% CI -0.09, -0.01), and total media exposure (β -0.19; 95% CI -0.29, -0.09) at 6 years. However, media exposure at 4 years was not associated with self-regulation at 6 years. Although media exposure duration at 2 years was associated with later self-regulation, and self-regulation at 4 years was associated with later media exposure, associations were of small magnitude. More research is needed examining content quality, social context, and mobile media use and child self-regulation. Copyright © 2018. Published by Elsevier Inc.

Targeting self-regulation to promote health behaviors in children.

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Miller, Alison L; Gearhardt, Ashley N; Fredericks, Emily M; Katz, Benjamin; Shapiro, Lilly Fink; Holden, Kelsie; Kaciroti, Niko; Gonzalez, Richard; Hunter, Christine; Lumeng, Julie C

2018-02-01

Poor self-regulation (i.e., inability to harness cognitive, emotional, motivational resources to achieve goals) is hypothesized to contribute to unhealthy behaviors across the lifespan. Enhancing early self-regulation may increase positive health outcomes. Obesity is a major public health concern with early-emerging precursors related to self-regulation; it is therefore a good model for understanding self-regulation and health behavior. Preadolescence is a transition when children increase autonomy in health behaviors (e.g., eating, exercise habits), many of which involve self-regulation. This paper presents the scientific rationale for examining self-regulation mechanisms that are hypothesized to relate to health behaviors, specifically obesogenic eating, that have not been examined in children. We describe novel intervention protocols designed to enhance self-regulation skills, specifically executive functioning, emotion regulation, future-oriented thinking, and approach bias. Interventions are delivered via home visits. Assays of self-regulation and obesogenic eating behaviors using behavioral tasks and self-reports are implemented and evaluated to determine feasibility and psychometrics and to test intervention effects. Participants are low-income 9-12 year-old children who have been phenotyped for self-regulation, stress, eating behavior and adiposity through early childhood. Study goals are to examine intervention effects on self-regulation and whether change in self-regulation improves obesogenic eating. Copyright © 2017 Elsevier Ltd. All rights reserved.

Maternal abuse history and self-regulation difficulties in preadolescence.

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Delker, Brianna C; Noll, Laura K; Kim, Hyoun K; Fisher, Philip A

2014-12-01

Although poor parenting is known to be closely linked to self-regulation difficulties in early childhood, comparatively little is understood about the role of other risk factors in the early caregiving environment (such as a parent's own experiences of childhood abuse) in developmental pathways of self-regulation into adolescence. Using a longitudinal design, this study aimed to examine how a mother's history of abuse in childhood relates to her offspring's self-regulation difficulties in preadolescence. Maternal controlling parenting and exposure to intimate partner aggression in the child's first 24-36 months were examined as important early social and environmental influences that may explain the proposed connection between maternal abuse history and preadolescent self-regulation. An ethnically diverse sample of mothers (N=488) who were identified as at-risk for child maltreatment was recruited at the time of their children's birth. Mothers and their children were assessed annually from the child's birth through 36 months, and at age 9-11 years. Structural equation modeling and bootstrap tests of indirect effects were conducted to address the study aims. Findings indicated that maternal abuse history indirectly predicted their children's self-regulation difficulties in preadolescence mainly through maternal controlling parenting in early childhood, but not through maternal exposure to aggression by an intimate partner. Maternal history of childhood abuse and maternal controlling parenting in her child's early life may have long-term developmental implications for child self-regulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Temperamental predictors of subjective well-being from early adolescence to mid-life: The role of temporal and energetic regulation.

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Bojanowska, Agnieszka; Zalewska, Anna M

2017-02-14

We investigated links between temperament traits described in Strelau's Regulative Theory of Temperament (Emotional Reactivity, Briskness, Activity, Endurance, Perseveration and Sensory Sensitivity) and subjective well-being (SWB)-Positive Affect, Negative Affect and Life Satisfaction as conceptualised by Diener. Participants representing early (n = 166) and late adolescence (n = 199), early (n = 195) and mid-adulthood (n = 156) filled out Formal Characteristics of Behaviour-Temperament Inventory, Positive and Negative Affect Schedule and Satisfaction with Life Scale. Results showed that higher Briskness, Endurance, Activity, lower Perseveration and Emotional Reactivity corresponded with higher SWB. They predicted 16% of affective components' and 7% of satisfaction variance. Each well-being component had a unique set of predictors; however, predictors of affective components varied across age groups. Higher Positive Affect was predicted by traits responsible for energetic regulation (higher Endurance and Activity and lower Emotional Reactivity) and by higher Perseveration, but their role (excluding Emotional Reactivity) was age-dependent. Higher Negative Affect was predicted by higher Emotional Reactivity and dimensions expressing temporal characteristics, lower Briskness and higher Perseveration (Perseveration was not significant among younger adolescents). Higher Satisfaction was steadily predicted by lower Emotional Reactivity and higher Activity. To conclude, the functions of temperament traits are mostly in line with theoretical expectations, but more complex than indicated by previous research. © 2017 The Authors. International Journal of Psychology published by John Wiley & Sons Ltd on behalf of International Union of Psychological Science.

Reaching Out to Send a Message: Proteins Associated with Neurite Outgrowth and Neurotransmission are Altered with Age in the Long-Lived Naked Mole-Rat.

Science.gov (United States)

Triplett, Judy C; Swomley, Aaron M; Kirk, Jessime; Grimes, Kelly M; Lewis, Kaitilyn N; Orr, Miranda E; Rodriguez, Karl A; Cai, Jian; Klein, Jon B; Buffenstein, Rochelle; Butterfield, D Allan

2016-07-01

Aging is the greatest risk factor for developing neurodegenerative diseases, which are associated with diminished neurotransmission as well as neuronal structure and function. However, several traits seemingly evolved to avert or delay age-related deterioration in the brain of the longest-lived rodent, the naked mole-rat (NMR). The NMR remarkably also exhibits negligible senescence, maintaining an extended healthspan for ~75 % of its life span. Using a proteomic approach, statistically significant changes with age in expression and/or phosphorylation levels of proteins associated with neurite outgrowth and neurotransmission were identified in the brain of the NMR and include: cofilin-1; collapsin response mediator protein 2; actin depolymerizing factor; spectrin alpha chain; septin-7; syntaxin-binding protein 1; synapsin-2 isoform IIB; and dynamin 1. We hypothesize that such changes may contribute to the extended lifespan and healthspan of the NMR.

Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation

Energy Technology Data Exchange (ETDEWEB)

Li, Ying [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Clinical Laboratory, Second Affiliated Hospital of Dalian Medical University, Dalian 116023 (China); Huang, Xiaohua [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Clinical Biochemistry, College of Laboratory Medicine, Dalian Medical University, Dalian 116044 (China); An, Yue [Department of Clinical Laboratory, Second Affiliated Hospital of Dalian Medical University, Dalian 116023 (China); Ren, Feng [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Yang, Zara Zhuyun; Zhu, Hongmei; Zhou, Lei [The Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Molecular and Clinical Medicine, Kunming Medical University, Kunming 650228 (China); Department of Anatomy and Developmental Biology, Monash University, Clayton 3800 (Australia); He, Xiaowen; Schachner, Melitta [Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, New Brunswick, NJ (United States); Xiao, Zhicheng, E-mail: zhicheng.xiao@monash.edu [The Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Molecular and Clinical Medicine, Kunming Medical University, Kunming 650228 (China); Department of Anatomy and Developmental Biology, Monash University, Clayton 3800 (Australia); Ma, Keli, E-mail: makeli666@aliyun.com [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Li, Yali, E-mail: yalilipaper@gmail.com [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Anatomy, National University of Singapore, Singapore 119078 (Singapore)

2013-10-25

Highlights: •Down-regulating FUT9 and ST3Gal4 expression blocks L1-induced neuronal differentiation of ESCs. •Up-regulating FUT9 and ST3Gal4 expression in L1-ESCs depends on the activation of PLCγ. •L1 promotes ESCs to differentiate into neuron through regulating cell surface glycosylation. -- Abstract: Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study, we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase Cγ (PLCγ) signaling pathway with either a specific PLCγ inhibitor or knockdown PLCγ reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression.

Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation

International Nuclear Information System (INIS)

Li, Ying; Huang, Xiaohua; An, Yue; Ren, Feng; Yang, Zara Zhuyun; Zhu, Hongmei; Zhou, Lei; He, Xiaowen; Schachner, Melitta; Xiao, Zhicheng; Ma, Keli; Li, Yali

2013-01-01

Highlights: •Down-regulating FUT9 and ST3Gal4 expression blocks L1-induced neuronal differentiation of ESCs. •Up-regulating FUT9 and ST3Gal4 expression in L1-ESCs depends on the activation of PLCγ. •L1 promotes ESCs to differentiate into neuron through regulating cell surface glycosylation. -- Abstract: Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study, we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase Cγ (PLCγ) signaling pathway with either a specific PLCγ inhibitor or knockdown PLCγ reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression

Disassembly of microtubules and inhibition of neurite outgrowth, neuroblastoma cell proliferation, and MAP kinase tyrosine dephosphorylation by dibenzyl trisulphide.

Science.gov (United States)

Rösner, H; Williams, L A; Jung, A; Kraus, W

2001-08-22

Dibenzyl trisulphide (DTS), a main lipophilic compound in Petiveria alliacea L. (Phytolaccaceae), was identified as one of the active immunomodulatory compounds in extracts of the plant. To learn more about its biological activities and molecular mechanisms, we conducted one-dimensional NMR interaction studies with bovine serum albumin (BSA) and tested DTS and related compounds in two well-established neuronal cell-and-tissue culture systems. We found that DTS preferentially binds to an aromatic region of BSA which is rich in tyrosyl residues. In SH-SY5Y neuroblastoma cells, DTS attenuates the dephosphorylation of tyrosyl residues of MAP kinase (erk1/erk2). In the same neuroblastoma cell line and in Wistar 38 human lung fibroblasts, DTS causes a reversible disassembly of microtubules, but it did not affect actin dynamics. Probably due to the disruption of the microtubule dynamics, DTS also inhibits neuroblastoma cell proliferation and neurite outgrowth from spinal cord explants. Related dibenzyl compounds with none, one, or two sulphur atoms were found to be significantly less effective. These data confirmed that the natural compound DTS has a diverse spectrum of biological properties, including cytostatic and neurotoxic actions in addition to immunomodulatory activities.

Immediate early gene activity-regulated cytoskeletal-associated protein regulates estradiol-induced lordosis behavior in female rats.

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Christensen, Amy; Dewing, Phoebe; Micevych, Pavel

2015-01-01

Sensory feedback is an important component of any behavior, with each instance influencing subsequent activity. Female sexual receptivity is mediated both by the steroid hormone milieu and interaction with the male. We tested the influence of repeated mating on the level of sexual receptivity in ovariectomized rats treated with estradiol benzoate (EB) once every fourth day to mimic the normal phasic changes of circulating estradiol. Females were divided into two groups: naïve, which were tested for lordosis behavior once, and experienced rats, which were tested for lordosis after each EB injection. To monitor the effect of mating, the number of neurons expressing the immediate early gene activity-regulated cytoskeleton-associated protein (Arc) were counted in the mediobasal hypothalamus. Females were unreceptive following the first EB treatment, but the mating induced Arc expression. In naïve rats, each subsequent EB injection increased the levels of sexual receptivity. This ramping was not observed in experienced rats, which achieved only a moderate level of sexual receptivity. However, experienced females treated with EB and progesterone were maximally receptive and did not have Arc expression. To test whether the expression of Arc attenuated lordosis, Arc antisense oligodeoxynucleotides (asODN) were microinjected into experienced females' arcuate nuclei. Arc expression was attenuated, and the experienced EB-treated females achieved maximal sexual receptivity. These results demonstrate that Arc expression in the hypothalamus might influence future sexual receptivity and provides evidence of learning in the arcuate nucleus. The loss of Arc results in unrestrained sexual receptivity. © 2014 Wiley Periodicals, Inc.

Sprouty4 is an endogenous negative modulator of TrkA signaling and neuronal differentiation induced by NGF.

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Fernando C Alsina

Full Text Available The Sprouty (Spry family of proteins represents endogenous regulators of downstream signaling pathways induced by receptor tyrosine kinases (RTKs. Using real time PCR, we detect a significant increase in the expression of Spry4 mRNA in response to NGF, indicating that Spry4 could modulate intracellular signaling pathways and biological processes induced by NGF and its receptor TrkA. In this work, we demonstrate that overexpression of wild-type Spry4 causes a significant reduction in MAPK and Rac1 activation and neurite outgrowth induced by NGF. At molecular level, our findings indicate that ectopic expression of a mutated form of Spry4 (Y53A, in which a conserved tyrosine residue was replaced, fail to block both TrkA-mediated Erk/MAPK activation and neurite outgrowth induced by NGF, suggesting that an intact tyrosine 53 site is required for the inhibitory effect of Spry4 on NGF signaling. Downregulation of Spry4 using small interference RNA knockdown experiments potentiates PC12 cell differentiation and MAPK activation in response to NGF. Together, these findings establish a new physiological mechanism through which Spry4 regulates neurite outgrowth reducing not only the MAPK pathway but also restricting Rac1 activation in response to NGF.

Early dissemination seeds metastasis in breast cancer

Science.gov (United States)

Hosseini, Hedayatollah; Obradović, Milan M.S.; Hoffmann, Martin; Harper, Kathryn; Sosa, Maria Soledad; Werner-Klein, Melanie; Nanduri, Lahiri Kanth; Werno, Christian; Ehrl, Carolin; Maneck, Matthias; Patwary, Nina; Haunschild, Gundula; Gužvić, Miodrag; Reimelt, Christian; Grauvogl, Michael; Eichner, Norbert; Weber, Florian; Hartkopf, Andreas; Taran, Florin-Andrei; Brucker, Sara Y.; Fehm, Tanja; Rack, Brigitte; Buchholz, Stefan; Spang, Rainer; Meister, Gunter; Aguirre-Ghiso, Julio A.; Klein, Christoph A.

2016-01-01

Accumulating data suggest that metastatic dissemination often occurs early during tumour formation but the mechanisms of early metastatic spread have not yet been addressed. Here, we studied metastasis in a HER2-driven mouse breast cancer model and found that progesterone-induced signalling triggered migration of cancer cells from early lesions shortly after HER2 activation, but promoted proliferation in advanced primary tumour cells. The switch from migration to proliferation was regulated by elevated HER2 expression and increased tumour cell density involving miRNA-mediated progesterone receptor (PGR) down-regulation and was reversible. Cells from early, low-density lesions displayed more stemness features than cells from dense, advanced tumours, migrated more and founded more metastases. Strikingly, we found that at least 80% of metastases were derived from early disseminated cancer cells (DCC). Karyotypic and phenotypic analysis of human disseminated cancer cells and primary tumours corroborated the relevance of these findings for human metastatic dissemination. PMID:27974799

Dealing with duplicate regulations and conflicting jurisdictions

International Nuclear Information System (INIS)

Aamodt, P.L.

1991-01-01

There are a number of situations where mixed wastes are regulated by dual regulations and regulators. This presentation attempts to show where such duplication exists and how it evolved historically through legislative actions. The presentation includes a discussion of strategies that have been used to deal with the problems that result from duplicate regulations and jurisdictional conflicts. The RCRA and AEA regulations are really more similar than dissimilar. There are significant issues that must be worked through with the regulators. It is most important to work with your regulators early in process. The following are suggestions for dealing with the regulators. (1) Know the regulations in advance of discussions. (2) Begin dialogue with the regulator(s) as early as possible and get to know the people you will be dealing with -- and let them know you. (3) Explain the technical/regulatory issues/problems that you face at your facility in sufficient detail that they are clearly understood, and work with the regulator(s) to reasonably address them in the language/requirements of the permit. (4) Always attempt to comply with the regulations first before going in with a variance request -- document your efforts, and be honest with your assessment of issues. (5) Don't be adversarial -- remember that the regulator has the same objectives as you do. 1 tab

Early cell death detection with digital holographic microscopy.

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Nicolas Pavillon

Full Text Available BACKGROUND: Digital holography provides a non-invasive measurement of the quantitative phase shifts induced by cells in culture, which can be related to cell volume changes. It has been shown previously that regulation of cell volume, in particular as it relates to ionic homeostasis, is crucially involved in the activation/inactivation of the cell death processes. We thus present here an application of digital holographic microscopy (DHM dedicated to early and label-free detection of cell death. METHODS AND FINDINGS: We provide quantitative measurements of phase signal obtained on mouse cortical neurons, and caused by early neuronal cell volume regulation triggered by excitotoxic concentrations of L-glutamate. We show that the efficiency of this early regulation of cell volume detected by DHM, is correlated with the occurrence of subsequent neuronal death assessed with the widely accepted trypan blue method for detection of cell viability. CONCLUSIONS: The determination of the phase signal by DHM provides a simple and rapid optical method for the early detection of cell death.

The Relations Between Maternal Prenatal Anxiety or Stress and Child's Early Negative Reactivity or Self-Regulation: A Systematic Review.

Science.gov (United States)

Korja, Riikka; Nolvi, Saara; Grant, Kerry Ann; McMahon, Cathy

2017-12-01

In the present review, we examine the association between maternal prenatal stress or anxiety and children's early negative reactivity or self-regulation. The review includes 32 studies that focus on pregnancy-related anxiety, state or trait anxiety, perceived stress, and stressful life events in relation to child's crying, temperament, or behavior during the first 2 years of life. We searched four electronic databases and 32 studies were selected based on the inclusion criteria. Twenty-three studies found an association between maternal prenatal anxiety or stress and a child's negative reactivity or self-regulation, and typically the effect sizes varied from low to moderate. The association was found regardless of the form of prenatal stress or anxiety and the trimester in which the prenatal stress or anxiety was measured. In conclusion, several forms of prenatal anxiety and stress may increase the risk of emotional and self-regulatory difficulties during the first 2 years of life.

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

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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.

Tyrosine pathway regulation is host-mediated in the pea aphid symbiosis during late embryonic and early larval development.

Science.gov (United States)

Rabatel, Andréane; Febvay, Gérard; Gaget, Karen; Duport, Gabrielle; Baa-Puyoulet, Patrice; Sapountzis, Panagiotis; Bendridi, Nadia; Rey, Marjolaine; Rahbé, Yvan; Charles, Hubert; Calevro, Federica; Colella, Stefano

2013-04-10

Nutritional symbioses play a central role in insects' adaptation to specialized diets and in their evolutionary success. The obligatory symbiosis between the pea aphid, Acyrthosiphon pisum, and the bacterium, Buchnera aphidicola, is no exception as it enables this important agricultural pest insect to develop on a diet exclusively based on plant phloem sap. The symbiotic bacteria provide the host with essential amino acids lacking in its diet but necessary for the rapid embryonic growth seen in the parthenogenetic viviparous reproduction of aphids. The aphid furnishes, in exchange, non-essential amino acids and other important metabolites. Understanding the regulations acting on this integrated metabolic system during the development of this insect is essential in elucidating aphid biology. We used a microarray-based approach to analyse gene expression in the late embryonic and the early larval stages of the pea aphid, characterizing, for the first time, the transcriptional profiles in these developmental phases. Our analyses allowed us to identify key genes in the phenylalanine, tyrosine and dopamine pathways and we identified ACYPI004243, one of the four genes encoding for the aspartate transaminase (E.C. 2.6.1.1), as specifically regulated during development. Indeed, the tyrosine biosynthetic pathway is crucial for the symbiotic metabolism as it is shared between the two partners, all the precursors being produced by B. aphidicola. Our microarray data are supported by HPLC amino acid analyses demonstrating an accumulation of tyrosine at the same developmental stages, with an up-regulation of the tyrosine biosynthetic genes. Tyrosine is also essential for the synthesis of cuticular proteins and it is an important precursor for cuticle maturation: together with the up-regulation of tyrosine biosynthesis, we observed an up-regulation of cuticular genes expression. We were also able to identify some amino acid transporter genes which are essential for the switch

DEAR1 is a dominant regulator of acinar morphogenesis and an independent predictor of local recurrence-free survival in early-onset breast cancer.

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Steven T Lott

2009-05-01

Full Text Available Breast cancer in young women tends to have a natural history of aggressive disease for which rates of recurrence are higher than in breast cancers detected later in life. Little is known about the genetic pathways that underlie early-onset breast cancer. Here we report the discovery of DEAR1 (ductal epithelium-associated RING Chromosome 1, a novel gene encoding a member of the TRIM (tripartite motif subfamily of RING finger proteins, and provide evidence for its role as a dominant regulator of acinar morphogenesis in the mammary gland and as an independent predictor of local recurrence-free survival in early-onset breast cancer.Suppression subtractive hybridization identified DEAR1 as a novel gene mapping to a region of high-frequency loss of heterozygosity (LOH in a number of histologically diverse human cancers within Chromosome 1p35.1. In the breast epithelium, DEAR1 expression is limited to the ductal and glandular epithelium and is down-regulated in transition to ductal carcinoma in situ (DCIS, an early histologic stage in breast tumorigenesis. DEAR1 missense mutations and homozygous deletion (HD were discovered in breast cancer cell lines and tumor samples. Introduction of the DEAR1 wild type and not the missense mutant alleles to complement a mutation in a breast cancer cell line, derived from a 36-year-old female with invasive breast cancer, initiated acinar morphogenesis in three-dimensional (3D basement membrane culture and restored tissue architecture reminiscent of normal acinar structures in the mammary gland in vivo. Stable knockdown of DEAR1 in immortalized human mammary epithelial cells (HMECs recapitulated the growth in 3D culture of breast cancer cell lines containing mutated DEAR1, in that shDEAR1 clones demonstrated disruption of tissue architecture, loss of apical basal polarity, diffuse apoptosis, and failure of lumen formation. Furthermore, immunohistochemical staining of a tissue microarray from a cohort of 123 young

Identification of let-7-regulated oncofetal genes

DEFF Research Database (Denmark)

Boyerinas, Benjamin; Park, Sun-Mi; Shomron, Noam

2008-01-01

-regulated at the end of embryonic development. Let-7 is often down-regulated early during cancer development, suggesting that let-7-regulated oncofetal genes (LOG) may become reexpressed in cancer cells. Using comparative bioinformatics, we have identified 12 conserved LOGs that include HMGA2 and IMP-1/CRD-BP. IMP-1...

Memories of early work on muscle contraction and regulation in the 1950's and 1960's

International Nuclear Information System (INIS)

Huxley, Hugh E.

2008-01-01

Professor Ebashi's epic work on the biochemistry of the regulation of muscle contraction began in the early 1950's, during the same period that work on the molecular basis of force production in muscle was also beginning. The latter work started in two MRC Research Units in the UK, and was continued jointly by the two workers from those Units who had, independently, gone to MIT to learn the new techniques of electron microscopy and to apply them to muscle. In a somewhat similar fashion, Professor Ebashi also spent one or two years in the USA, continuing his work on the role of calcium in muscle regulation in Lippman's laboratory, before returning to Japan to achieve the great breakthroughs in this work during the 1960's. Hanson and Huxley, after putting forward the overlapping actin and myosin filament arrays model for the striated muscle sarcomere, and subsequently the sliding filament model of muscle contraction (simultaneously with A.F Huxley and R. Niedergerke), returned to the UK to pursue detailed structural studies in separate Research Units, in a mixture of consultation, collaboration, and competition, during the later 1950's and throughout the 1960's. However, the path to enlightenment described here in some detail was somewhat more tortuous than the standard literature perhaps reveals. Nevertheless, by the time of the Cold Spring Harbor Symposium on Muscle Contraction in 1972, the two lines of enquiry on regulation itself, and on the tilting cross-bridge model of force production, had arrived at a good deal of common ground, and indeed the identification of troponin and its periodic distribution along the actin filaments had helped resolve a long-standing puzzle in the interpretation of the low angle X-ray diagram. Since then, an enormous amount of remarkable new work has been necessary to establish troponin regulation and the tilting cross-bridge mechanism in molecular detail, but the work in the 1950's and 1960's has provided a firm and accurate basis

Dendritic Actin Cytoskeleton: Structure, Functions, and Regulations

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Anja Konietzny

2017-05-01

Full Text Available Actin is a versatile and ubiquitous cytoskeletal protein that plays a major role in both the establishment and the maintenance of neuronal polarity. For a long time, the most prominent roles that were attributed to actin in neurons were the movement of growth cones, polarized cargo sorting at the axon initial segment, and the dynamic plasticity of dendritic spines, since those compartments contain large accumulations of actin filaments (F-actin that can be readily visualized using electron- and fluorescence microscopy. With the development of super-resolution microscopy in the past few years, previously unknown structures of the actin cytoskeleton have been uncovered: a periodic lattice consisting of actin and spectrin seems to pervade not only the whole axon, but also dendrites and even the necks of dendritic spines. Apart from that striking feature, patches of F-actin and deep actin filament bundles have been described along the lengths of neurites. So far, research has been focused on the specific roles of actin in the axon, while it is becoming more and more apparent that in the dendrite, actin is not only confined to dendritic spines, but serves many additional and important functions. In this review, we focus on recent developments regarding the role of actin in dendrite morphology, the regulation of actin dynamics by internal and external factors, and the role of F-actin in dendritic protein trafficking.

CDDO and ATRA Instigate Differentiation of IMR32 Human Neuroblastoma Cells

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Namrata Chaudhari

2017-09-01

Full Text Available Neuroblastoma is the most common solid extra cranial tumor in infants. Improving the clinical outcome of children with aggressive tumors undergoing one of the multiple treatment options has been a major concern. Differentiating neuroblastoma cells holds promise in inducing tumor growth arrest and treating minimal residual disease. In this study, we investigated the effect of partial PPARγ agonist 2-cyano-3,12-dioxooleana-1,9(11-dien-28-oic acid (CDDO on human neuroblastoma IMR32 cells. Our results demonstrate that treatment with low concentration of CDDO and particularly in combination with all trans retinoic acid (ATRA induced neurite outgrowth, increased the percentage of more than two neurites bearing cells, and decreased viability in IMR32 cells. These morphological changes were associated with an increase in expression of bonafide differentiation markers like β3-tubulin and Neuron Specific Enolase (NSE. The differentiation was accompanied by a decrease in the expression of MYCN whose amplification is known to contribute to the pathogenesis of neuroblastoma. MYCN is known to negatively regulate NMYC downstream-regulated gene 1 (NDRG1 in neuroblastomas. MYCN down-regulation induced by CDDO correlated with increased expression of NDRG1. CDDO decreased Anaplastic Lymphoma Kinase (ALK mRNA expression without affecting its protein level, while ATRA significantly down-regulated ALK. Antagonism of PPARγ receptor by T0070907 meddled with differentiation inducing effects of CDDO as observed by stunted neurite growth, increased viability and decreased expression of differentiation markers. Our findings indicate that IMR32 differentiation induced by CDDO in combination with ATRA enhances, differentiation followed by cell death via cAMP-response-element binding protein (CREB independent and PPARγ dependent signaling mechanisms.

A natural diarylheptanoid promotes neuronal differentiation via activating ERK and PI3K-Akt dependent pathways.

Science.gov (United States)

Tang, G; Dong, X; Huang, X; Huang, X-J; Liu, H; Wang, Y; Ye, W-C; Shi, L

2015-09-10

Neuronal differentiation is a critical developmental process that determines accurate synaptic connection and circuit wiring. A wide variety of naturally occurring compounds have been shown as promising drug leads for the generation and differentiation of neurons. Here we report that a diarylheptanoid from the plant Alpinia officinarum, 7-(4-hydroxyphenyl)-1-phenyl-4E-hepten-3-one (Cpd 1), exhibited potent activities in neuronal differentiation and neurite outgrowth. Cpd 1 induced differentiation of neuroblastoma Neuro-2a cells into a neuron-like morphology, and accelerated the establishment of axon-dendrite polarization of cultured hippocampal neurons. Moreover, Cpd 1 promoted neurite extension in both Neuro-2a cells and neurons. We showed that the effects of Cpd 1 on neuronal differentiation and neurite growth were specifically dependent on the activation of extracellular signal-regulated kinases (ERKs) and phosphoinositide 3-kinase (PI3K)-Akt signaling pathways. Importantly, intraperitoneal administration of Cpd 1 promoted the differentiation of new-born progenitor cells into mature neurons in the adult hippocampal dentate gyrus. Collectively, this study identifies a naturally occurring diarylheptanoid with beneficial effects on neuronal differentiation and neurite outgrowth in vitro and in vivo. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Function of JARID2 in bovines during early embryonic development

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Yao Fu

2017-12-01

Full Text Available Histone lysine modifications are important epigenetic modifications in early embryonic development. JARID2, which is a member of the jumonji demethylase protein family, is a regulator of early embryonic development and can regulate mouse development and embryonic stem cell (ESC differentiation by modifying histone lysines. JARID2 can affect early embryonic development by regulating the methylation level of H3K27me3, which is closely related to normal early embryonic development. To investigate the expression pattern of JARID2 and the effect of JARID2-induced H3K27 methylation in bovine oocytes and early embryonic stages, JARID2 mRNA expression and localization were detected in bovine oocytes and early embryos via qRT-PCR and immunofluorescence in the present study. The results showed that JARID2 is highly expressed in the germinal vesicle (GV, MII, 2-cell, 4-cell, 8-cell, 16-cell and blastocyst stages, but the relative expression level of JARID2 in bovine GV oocytes is significantly lower than that at other oocyte/embryonic stages (p < 0.05, and JARID2 is expressed primarily in the nucleus. We next detected the mRNA expression levels of embryonic development-related genes (OCT4, SOX2 and c-myc after JARID2 knockdown through JARID2-2830-siRNA microinjection to investigate the molecularpathwayunderlying the regulation of H3K27me3 by JARID2 during early embryonic development. The results showed that the relative expression levels of these genes in 2-cell embryos weresignificantly higher than those in the blastocyst stage, and expression levels were significantly increased after JARID2 knockdown. In summary, the present study identified the expression pattern of JARID2 in bovine oocytes and at each early embryonic stage, and the results suggest that JARID2 plays a key role in early embryonic development by regulating the expression of OCT4, SOX2 and c-myc via modification of H3K27me3 expression. This work provides new data for improvements in the

p27Kip1 Modulates Axonal Transport by Regulating α-Tubulin Acetyltransferase 1 Stability

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Giovanni Morelli

2018-05-01

Full Text Available Summary: The protein p27Kip1 plays roles that extend beyond cell-cycle regulation during cerebral cortex development, such as the regulation of neuronal migration and neurite branching via signaling pathways that converge on the actin and microtubule cytoskeletons. Microtubule-dependent transport is essential for the maturation of neurons and the establishment of neuronal connectivity though synapse formation and maintenance. Here, we show that p27Kip1 controls the transport of vesicles and organelles along the axon of mice cortical projection neurons in vitro. Moreover, suppression of the p27Kip1 ortholog, dacapo, in Drosophila melanogaster disrupts axonal transport in vivo, leading to the reduction of locomotor activity in third instar larvae and adult flies. At the molecular level, p27Kip1 stabilizes the α-tubulin acetyltransferase 1, thereby promoting the acetylation of microtubules, a post-translational modification required for proper axonal transport. : Morelli et al. report that p27Kip1/Dacapo modulates the acetylation of microtubules in axons via stabilization of ATAT1, the main α-tubulin acetyltransferase. Its conditional loss leads to the reduction of bidirectional axonal transport of vesicles and mitochondria in vitro in mice and in vivo in Drosophila. Keywords: p27Kip1, dacapo, acetylation, axonal transport, ATAT1, alpha-tubulin, HDAC6, Drosophila, mouse, cerebral cortex

Industrial Innovation and Environmental Regulation: Developing ...

International Development Research Centre (IDRC) Digital Library (Canada)

What role should governments play in protecting the environment and controlling the environmental impacts of industry? Do regulations benefit the environment, and how do they affect industrial innovation? Since the modern era of environmental management began in the early 1970s, regulations have been used with ...

Flotillin-1 is an evolutionary-conserved memory-related protein up-regulated in implicit and explicit learning paradigms.

Science.gov (United States)

Monje, Francisco J; Divisch, Isabella; Demit, Marvie; Lubec, Gert; Pollak, Daniela D

2013-06-01

Studies of synaptic plasticity using the marine mollusk Aplysia californica as model system have been successfully used to identify proteins involved in learning and memory. The importance of molecular elements regulated by the learning- related neurotransmitter serotonin in Aplysia can then be explored in rodent models and finally tested for their relevance for human physiology and pathology. Herein, 2-DE gel-based electrophoresis has been used to investigate protein level changes after treatment with serotonin in Aplysia abdominal ganglia. Twenty-one proteins have been found to be regulated by serotonin, and protein level changes of actin depolymerizing factor (ADF), deleted in azoospermia associated protein (DAZAP-1), and Flotillin-1 have been verified by Western blotting. Flotillin-1, a member of the flotillin/reggie family of scaffolding proteins, has been previously found to be involved in neuritic branching and synapse formation in hippocampal neurons in vitro. However, its importance for hippocampal- dependent learning and memory in the mouse has not been examined. Here, elevated levels of Flotillin-1 in hippocampal tissue of mice trained in the Morris water maze confirmed the relevance of Flotillin-1 for memory-related processes in a mammalian system. Thus, a translational approach-from invertebrates to rodents-led to the identification of Flotillin-1 as evolutionary-conserved memory-related protein.

The dynamics of connexin expression, degradation and localisation are regulated by gonadotropins during the early stages of in vitro maturation of swine oocytes.

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Nicolas Santiquet

Full Text Available Gap junctional communication (GJC plays a primordial role in oocyte maturation and meiotic resumption in mammals by directing the transfer of numerous molecules between cumulus cells and the oocyte. Gap junctions are made of connexins (Cx, proteins that regulate GJC in numerous ways. Understanding the dynamic regulation of connexin arrangements during in vitro maturation (IVM could provide a powerful tool for controlling meiotic resumption and consequently in vitro development of fully competent oocytes. However, physiological events happening during the early hours of IVM may still be elucidated. The present study reports the dynamic regulation of connexin expression, degradation and localization during this stage. Cx43, Cx45 and Cx60 were identified as the main connexins expressed in swine COC. Cx43 and Cx45 transcripts were judged too static to be a regulator of GJC, while Cx43 protein expression was highly responsive to gonadotropins, suggesting that it might be the principal regulator of GJC. In addition, the degradation of Cx43 expressed after 4.5 h of IVM in response to equine chorionic gonadotropin appeared to involve the proteasomal complex. Cx43 localisation appeared to be associated with GJC. Taken together, these results show for the first time that gonadotropins regulate Cx43 protein expression, degradation and localisation in porcine COC during the first several hours of IVM. Regulation of Cx43 may in turn, via GJC, participate in the development of fully competent oocytes.

SnoN facilitates axonal regeneration after spinal cord injury.

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Jiun L Do

Full Text Available Adult CNS neurons exhibit a reduced capacity for growth compared to developing neurons, due in part to downregulation of growth-associated genes as development is completed. We tested the hypothesis that SnoN, an embryonically regulated transcription factor that specifies growth of the axonal compartment, can enhance growth in injured adult neurons. In vitro, SnoN overexpression in dissociated adult DRG neuronal cultures significantly enhanced neurite outgrowth. Moreover, TGF-β1, a negative regulator of SnoN, inhibited neurite outgrowth, and SnoN over-expression overcame this inhibition. We then examined whether SnoN influenced axonal regeneration in vivo: indeed, expression of a mutant form of SnoN resistant to degradation significantly enhanced axonal regeneration following cervical spinal cord injury, despite peri-lesional upregulation of TGF-β1. Thus, a developmental mechanism that specifies extension of the axonal compartment also promotes axonal regeneration after adult CNS injury.

Nutrient management regulations in The Netherlands

NARCIS (Netherlands)

Schröder, J.J.; Neeteson, J.J.

2008-01-01

The application of nutrients affect the quality of the environment which justifies the consideration of regulations regarding their use in agriculture. In the early 1990s The Netherlands decided to use the indicator `nutrient surplus at farm level¿ as the basis for a regulation which was called the

From External Regulation to Self-Regulation: Early Parenting Precursors of Young Children's Executive Functioning

Science.gov (United States)

Bernier, Annie; Carlson, Stephanie M.; Whipple, Natasha

2010-01-01

In keeping with proposals emphasizing the role of early experience in infant brain development, this study investigated the prospective links between quality of parent-infant interactions and subsequent child executive functioning (EF), including working memory, impulse control, and set shifting. Maternal sensitivity, mind-mindedness and autonomy…

The microtubule-associated protein 1A (MAP1A) is an early molecular target of soluble Aβ-peptide

DEFF Research Database (Denmark)

Clemmensen, C; Aznar, S; Knudsen, G M

2012-01-01

that microtubule rearrangements may be proximate to neuritic degeneration and deficits in episodic declarative memory. Here, we examined primary cortical neurons for changes in markers associated with synaptic function following exposure to sublethal concentrations of non-aggregated Aβ-peptide. This data show...

Vasopressin up-regulates the expression of growth-related immediate-early genes via two distinct EGF receptor transactivation pathways

Science.gov (United States)

Fuentes, Lida Q.; Reyes, Carlos E.; Sarmiento, José M.; Villanueva, Carolina I.; Figueroa, Carlos D.; Navarro, Javier; González, Carlos B.

2008-01-01

Activation of V1a receptor triggers the expression of growth-related immediate-early genes (IEGs), including c-Fos and Egr-1. Here we found that pre-treatment of rat vascular smooth muscle A-10 cell line with the EGF receptor inhibitor AG1478 or the over-expression of an EGFR dominant negative mutant (HEBCD533) blocked the vasopressin-induced expression of IEGs, suggesting that activation of these early genes mediated by V1a receptor is via transactivation of the EGF receptor. Importantly, the inhibition of the metalloproteinases, which catalyzed the shedding of the EGF receptor agonist HB-EGF, selectively blocked the vasopressin-induced expression c-Fos. On the other hand, the inhibition of c-Src selectively blocked the vasopressin-induced expression of Egr-1. Interestingly, in contrast to the expression of c-Fos, the expression of Egr-1 was mediated via the Ras/MEK/MAPK-dependent signalling pathway. Vasopressin-triggered expression of both genes required the release of intracellular calcium, activation of PKC and β-arrestin 2. These findings demonstrated that vasopressin up-regulated the expression of c-Fos and Erg-1 via transactivation of two distinct EGF receptor-dependent signalling pathways. PMID:18571897

Neurite Outgrowth and Neuroprotective Effects of Quercetin from Caesalpinia mimosoides Lamk. on Cultured P19-Derived Neurons

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Napat Tangsaengvit

2013-01-01

Full Text Available Quercetin has been isolated for the first time from ethyl acetate extract of Caesalpinia mimosoides Lamk. C. mimosoides Lamk. (Fabaceae or Cha rueat (Thai name is an indigenous plant found in mixed deciduous forest in northern and north-eastern parts of Thailand. Thai rural people consume its young shoots and leaves as a fresh vegetable, as well as it is used for medicinal purposes.The antioxidant capacity in terms of radical scavenging activity of quercetin was determined as IC50 of 3.18 ± 0.07 µg/mL, which was higher than that of Trolox and ascorbic acid (12.54 ± 0.89 and 10.52 ± 0.48 µg/mL, resp.. The suppressive effect of quercetin on both purified and cellular acetylcholinesterase (AChE enzymes was investigated as IC50 56.84 ± 2.64 and 36.60 ± 2.78 µg/mL, respectively. In order to further investigate the protective ability of quercetin on neuronal cells, P19-derived neurons were used as a neuronal model in this study. As a result, quercetin at a very low dose of 1 nM enhanced survival and induced neurite outgrowth of P19-derived neurons. Furthermore, this flavonoid also possessed significant protection against oxidative stress induced by serum deprivation. Altogether, these findings suggest that quercetin is a multifunctional compound and promising valuable drugs candidate for the treatment of neurodegenerative disease.

Dynamic range of Nef-mediated evasion of HLA class II-restricted immune responses in early HIV-1 infection.

Science.gov (United States)

Mahiti, Macdonald; Brumme, Zabrina L; Jessen, Heiko; Brockman, Mark A; Ueno, Takamasa

2015-07-31

HLA class II-restricted CD4(+) T lymphocytes play an important role in controlling HIV-1 replication, especially in the acute/early infection stage. But, HIV-1 Nef counteracts this immune response by down-regulating HLA-DR and up-regulating the invariant chain associated with immature HLA-II (Ii). Although functional heterogeneity of various Nef activities, including down-regulation of HLA class I (HLA-I), is well documented, our understanding of Nef-mediated evasion of HLA-II-restricted immune responses during acute/early infection remains limited. Here, we examined the ability of Nef clones from 47 subjects with acute/early progressive infection and 46 subjects with chronic progressive infection to up-regulate Ii and down-regulate HLA-DR and HLA-I from the surface of HIV-infected cells. HLA-I down-regulation function was preserved among acute/early Nef clones, whereas both HLA-DR down-regulation and Ii up-regulation functions displayed relatively broad dynamic ranges. Nef's ability to down-regulate HLA-DR and up-regulate Ii correlated positively at this stage, suggesting they are functionally linked in vivo. Acute/early Nef clones also exhibited higher HLA-DR down-regulation and lower Ii up-regulation functions compared to chronic Nef clones. Taken together, our results support enhanced Nef-mediated HLA class II immune evasion activities in acute/early compared to chronic infection, highlighting the potential importance of these functions following transmission. Copyright © 2015 Elsevier Inc. All rights reserved.

Early gene regulation of osteogenesis in embryonic stem cells

KAUST Repository

Kirkham, Glen R.; Lovrics, Anna; Byrne, Helen M.; Jensen, Oliver E.; King, John R.; Shakesheff, Kevin M.; Buttery, Lee D. K.

2012-01-01

The early gene regulatory networks (GRNs) that mediate stem cell differentiation are complex, and the underlying regulatory associations can be difficult to map accurately. In this study, the expression profiles of the genes Dlx5, Msx2 and Runx2

CDKL5, a protein associated with rett syndrome, regulates neuronal morphogenesis via Rac1 signaling.

Science.gov (United States)

Chen, Qian; Zhu, Yong-Chuan; Yu, Jing; Miao, Sheng; Zheng, Jing; Xu, Li; Zhou, Yang; Li, Dan; Zhang, Chi; Tao, Jiong; Xiong, Zhi-Qi

2010-09-22

Mutations in cyclin-dependent kinase-like 5 (CDKL5), also known as serine/threonine kinase 9 (STK9), have been identified in patients with Rett syndrome (RTT) and X-linked infantile spasm. However, the function of CDKL5 in the brain remains unknown. Here, we report that CDKL5 is a critical regulator of neuronal morphogenesis. We identified a neuron-specific splicing variant of CDKL5 whose expression was markedly induced during postnatal development of the rat brain. Downregulating CDKL5 by RNA interference (RNAi) in cultured cortical neurons inhibited neurite growth and dendritic arborization, whereas overexpressing CDKL5 had opposite effects. Furthermore, knocking down CDKL5 in the rat brain by in utero electroporation resulted in delayed neuronal migration, and severely impaired dendritic arborization. In contrast to its proposed function in the nucleus, we found that CDKL5 regulated dendrite development through a cytoplasmic mechanism. In fibroblasts and in neurons, CDKL5 colocalized and formed a protein complex with Rac1, a critical regulator of actin remodeling and neuronal morphogenesis. Overexpression of Rac1 prevented the inhibition of dendrite growth caused by CDKL5 knockdown, and the growth-promoting effect of ectopically expressed CDKL5 on dendrites was abolished by coexpressing a dominant-negative form of Rac1. Moreover, CDKL5 was required for brain-derived neurotrophic factor (BDNF)-induced activation of Rac1. Together, these results demonstrate a critical role of CDKL5 in neuronal morphogenesis and identify a Rho GTPase signaling pathway which may contribute to CDKL5-related disorders.

Early Prediction of Student Self-Regulation Strategies by Combining Multiple Models

Science.gov (United States)

Sabourin, Jennifer L.; Mott, Bradford W.; Lester, James C.

2012-01-01

Self-regulated learning behaviors such as goal setting and monitoring have been found to be crucial to students' success in computer-based learning environments. Consequently, understanding students' self-regulated learning behavior has been the subject of increasing interest. Unfortunately, monitoring these behaviors in real-time has proven…

Early gene regulation of osteogenesis in embryonic stem cells

KAUST Repository

Kirkham, Glen R.

2012-01-01

The early gene regulatory networks (GRNs) that mediate stem cell differentiation are complex, and the underlying regulatory associations can be difficult to map accurately. In this study, the expression profiles of the genes Dlx5, Msx2 and Runx2 in mouse embryonic stem cells were monitored over a 48 hour period after exposure to the growth factors BMP2 and TGFβ1. Candidate GRNs of early osteogenesis were constructed based on published experimental findings and simulation results of Boolean and ordinary differential equation models were compared with our experimental data in order to test the validity of these models. Three gene regulatory networks were found to be consistent with the data, one of these networks exhibited sustained oscillation, a behaviour which is consistent with the general view of embryonic stem cell plasticity. The work cycle presented in this paper illustrates how mathematical modelling can be used to elucidate from gene expression profiles GRNs that are consistent with experimental data. © 2012 The Royal Society of Chemistry.

Avaliação da limitação das atividades diárias e qualidade de vida de pacientes com hanseníase submetidos à cirurgia de neurólise para tratamento das neurites

OpenAIRE

Reis,Felipe José Jandre dos; Gomes,Maria Kátia; Cunha,Antonio José Ledo Alves da

2013-01-01

A neurólise é indicada para reduzir o ­sofrimento neural e impedir a instalação de sequelas e incapacidades em pacientes com hanseníase. O objetivo deste estudo foi verificar o grau de limitação das atividades e a qualidade de vida de pacientes com hanseníase submetidos a neurólise para tratamento das neurites. Participaram do estudo os pacientes submetidos à neurólise no período de 1998 a 2011. Foram coletadas informações sociodemográficas e clínicas, limitações das atividades (SALSA) e a qu...

Porcine SLITRK1

DEFF Research Database (Denmark)

Larsen, Knud Erik; Momeni, Jamal; Farajzadeh, Leila

2014-01-01

The membrane protein SLITRK1 functions as a developmentally regulated stimulator of neurite outgrowth and variants in this gene have been implicated in Tourette syndrome. In the current study we have cloned and characterized the porcine SLITRK1 gene. The genomic organization of SLITRK1 lacks...

Toll-like receptors in brain development and homeostasis

DEFF Research Database (Denmark)

Larsen, Peter H; Holm, Thomas Hellesøe; Owens, Trevor

2007-01-01

Toll-like receptors (TLRs) are best known as initiators of the innate immune response to pathogens. Recent reports now reveal intriguing roles for TLRs in the central nervous system (CNS). These include the regulation of neuroinflammation and of neurite outgrowth. The archetypal Toll protein in D...

Getting Back to the Woods: Familial Perspectives on Culture and Preschoolers' Acquisition of Self-Regulation and Emotion Regulation

Science.gov (United States)

Boyer, Wanda

2013-01-01

Discourse on culture is vital to early childhood educators' understanding of the young child in various socio-cultural experiences in family and community settings. In this article, the author will present a contemporary definition of culture. This article will then discuss the developmental constructs of self-regulation and emotion regulation and…

fNIRS Evidence of Prefrontal Regulation of Frustration in Early Childhood

OpenAIRE

Perlman, Susan B.; Luna, Beatriz; Hein, Tyler C.; Huppert, Theodore J.

2013-01-01

The experience of frustration is common in early childhood, yet some children seem to possess a lower tolerance for frustration than others. Characterizing the biological mechanisms underlying a wide range of frustration tolerance observed in early childhood may inform maladaptive behavior and psychopathology that is associated with this construct. The goal of this study was to measure prefrontal correlates of frustration in 3–5 year-old children, who are not readily adaptable for typical neu...

Individual differences in early adolescents' latent trait cortisol: Interaction of early adversity and 5-HTTLPR.

Science.gov (United States)

Chen, Frances R; Stroud, Catherine B; Vrshek-Schallhorn, Suzanne; Doane, Leah D; Granger, Douglas A

2017-10-01

The present study aimed to examine the interaction of 5-HTTLPR and early adversity on trait-like levels of cortisol. A community sample of 117 early adolescent girls (M age=12.39years) provided DNA samples for 5-HTTLPR genotyping, and saliva samples for assessing cortisol 3 times a day (waking, 30min post-waking, and bedtime) over a three-day period. Latent trait cortisol (LTC) was modeled using the first 2 samples of each day. Early adversity was assessed with objective contextual stress interviews with adolescents and their mothers. A significant 5-HTTLPR×early adversity interaction indicated that greater early adversity was associated with lower LTC levels, but only among individuals with either L/L or S/L genotype. Findings suggest that serotonergic genetic variation may influence the impact of early adversity on individual differences in HPA-axis regulation. Future research should explore whether this interaction contributes to the development of psychopathology through HPA axis functioning. Copyright © 2017 Elsevier B.V. All rights reserved.

Is credit for early action credible early action?

International Nuclear Information System (INIS)

Rolfe, C.; Michaelowa, A.; Dutschke, M.

1999-12-01

cannot participate effectively in the credit for early action program. Credit for early action could have major distributive effects while having very limited environmental impact. Credit for early action is inherently more complex and requires more administrative management and regulation than well-designed market instruments, and credit for early action may not counteract the disincentives created by the possibility of grandfathering. 22 refs., 7 figs

Inducible cAMP early repressor acts as a negative regulator for kindling epileptogenesis and long-term fear memory.

Science.gov (United States)

Kojima, Nobuhiko; Borlikova, Gilyana; Sakamoto, Toshiro; Yamada, Kazuyuki; Ikeda, Toshio; Itohara, Shigeyoshi; Niki, Hiroaki; Endo, Shogo

2008-06-18

Long-lasting neuronal plasticity as well as long-term memory (LTM) requires de novo synthesis of proteins through dynamic regulation of gene expression. cAMP-responsive element (CRE)-mediated gene transcription occurs in an activity-dependent manner and plays a pivotal role in neuronal plasticity and LTM in a variety of species. To study the physiological role of inducible cAMP early repressor (ICER), a CRE-mediated gene transcription repressor, in neuronal plasticity and LTM, we generated two types of ICER mutant mice: ICER-overexpressing (OE) mice and ICER-specific knock-out (KO) mice. Both ICER-OE and ICER-KO mice show no apparent abnormalities in their development and reproduction. A comprehensive battery of behavioral tests revealed no robust changes in locomotor activity, sensory and motor functions, and emotional responses in the mutant mice. However, long-term conditioned fear memory was attenuated in ICER-OE mice and enhanced in ICER-KO mice without concurrent changes in short-term fear memory. Furthermore, ICER-OE mice exhibited retardation of kindling development, whereas ICER-KO mice exhibited acceleration of kindling. These results strongly suggest that ICER negatively regulates the neuronal processes required for long-term fear memory and neuronal plasticity underlying kindling epileptogenesis, possibly through suppression of CRE-mediated gene transcription.

EZH2 regulates neuroblastoma cell differentiation via NTRK1 promoter epigenetic modifications.

Science.gov (United States)

Li, Zhenghao; Takenobu, Hisanori; Setyawati, Amallia Nuggetsiana; Akita, Nobuhiro; Haruta, Masayuki; Satoh, Shunpei; Shinno, Yoshitaka; Chikaraishi, Koji; Mukae, Kyosuke; Akter, Jesmin; Sugino, Ryuichi P; Nakazawa, Atsuko; Nakagawara, Akira; Aburatani, Hiroyuki; Ohira, Miki; Kamijo, Takehiko

2018-05-01

The polycomb repressor complex 2 molecule EZH2 is now known to play a role in essential cellular processes, namely, cell fate decisions, cell cycle regulation, senescence, cell differentiation, and cancer development/progression. EZH2 inhibitors have recently been developed; however, their effectiveness and underlying molecular mechanisms in many malignancies have not yet been elucidated in detail. Although the functional role of EZH2 in tumorigenesis in neuroblastoma (NB) has been investigated, mutations of EZH2 have not been reported. A Kaplan-Meier analysis on the event free survival and overall survival of NB patients indicated that the high expression of EZH2 correlated with an unfavorable prognosis. In order to elucidate the functional roles of EZH2 in NB tumorigenesis and its aggressiveness, we knocked down EZH2 in NB cell lines using lentivirus systems. The knockdown of EZH2 significantly induced NB cell differentiation, e.g., neurite extension, and the neuronal differentiation markers, NF68 and GAP43. EZH2 inhibitors also induced NB cell differentiation. We performed a comprehensive transcriptome analysis using Human Gene Expression Microarrays and found that NTRK1 (TrkA) is one of the EZH2-related suppression targets. The depletion of NTRK1 canceled EZH2 knockdown-induced NB cell differentiation. Our integrative methylome, transcriptome, and chromatin immunoprecipitation assays using NB cell lines and clinical samples clarified that the NTRK1 P1 and P2 promoter regions were regulated differently by DNA methylation and EZH2-related histone modifications. The NTRK1 transcript variants 1/2, which were regulated by EZH2-related H3K27me3 modifications at the P1 promoter region, were strongly expressed in favorable, but not unfavorable NB. The depletion and inhibition of EZH2 successfully induced NTRK1 transcripts and functional proteins. Collectively, these results indicate that EZH2 plays important roles in preventing the differentiation of NB cells and also

The molluscan RING-finger protein L-TRIM is essential for neuronal outgrowth

NARCIS (Netherlands)

van Diepen, M. T.; Spencer, G.E.; Minnen, J.; Gouwenberg, Y.; Bouwman, J.G.; Smit, A. B.; van Kesteren, R.E.

2005-01-01

The tripartite motif proteins TRIM-2 and TRIM-3 have been put forward as putative organizers of neuronal outgrowth and structural plasticity. Here, we identified a molluscan orthologue of TRIM-2/3, named L-TRIM, which is up-regulated during in vitro neurite outgrowth of central neurons. In adult

Transcriptomic responses in mouse brain exposed to chronic excess of the neurotransmitter glutamate

Directory of Open Access Journals (Sweden)

Pal Ranu

2010-06-01

Full Text Available Abstract Background Increases during aging in extracellular levels of glutamate (Glu, the major excitatory neurotransmitter in the brain, may be linked to chronic neurodegenerative diseases. Little is known about the molecular responses of neurons to chronic, moderate increases in Glu levels. Genome-wide gene expression in brain hippocampus was examined in a unique transgenic (Tg mouse model that exhibits moderate Glu hyperactivity throughout the lifespan, the neuronal Glutamate dehydrogenase (Glud1 mouse, and littermate 9 month-old wild type mice. Results Integrated bioinformatic analyses on transcriptomic data were used to identify bio-functions, pathways and gene networks underlying neuronal responses to increased Glu synaptic release. Bio-functions and pathways up-regulated in Tg mice were those associated with oxidative stress, cell injury, inflammation, nervous system development, neuronal growth, and synaptic transmission. Increased gene expression in these functions and pathways indicated apparent compensatory responses offering protection against stress, promoting growth of neuronal processes (neurites and re-establishment of synapses. The transcription of a key gene in the neurite growth network, the kinase Ptk2b, was significantly up-regulated in Tg mice as was the activated (phosphorylated form of the protein. In addition to genes related to neurite growth and synaptic development, those associated with neuronal vesicle trafficking in the Huntington's disease signalling pathway, were also up-regulated. Conclusions This is the first study attempting to define neuronal gene expression patterns in response to chronic, endogenous Glu hyperactivity at brain synapses. The patterns observed were characterized by a combination of responses to stress and stimulation of nerve growth, intracellular transport and recovery.

Drosophila Kismet regulates histone H3 lysine 27 methylation and early elongation by RNA polymerase II.

Directory of Open Access Journals (Sweden)

Shrividhya Srinivasan

2008-10-01

Full Text Available Polycomb and trithorax group proteins regulate cellular pluripotency and differentiation by maintaining hereditable states of transcription. Many Polycomb and trithorax group proteins have been implicated in the covalent modification or remodeling of chromatin, but how they interact with each other and the general transcription machinery to regulate transcription is not well understood. The trithorax group protein Kismet-L (KIS-L is a member of the CHD subfamily of chromatin-remodeling factors that plays a global role in transcription by RNA polymerase II (Pol II. Mutations in CHD7, the human counterpart of kis, are associated with CHARGE syndrome, a developmental disorder affecting multiple tissues and organs. To clarify how KIS-L activates gene expression and counteracts Polycomb group silencing, we characterized defects resulting from the loss of KIS-L function in Drosophila. These studies revealed that KIS-L acts downstream of P-TEFb recruitment to stimulate elongation by Pol II. The presence of two chromodomains in KIS-L suggested that its recruitment or function might be regulated by the methylation of histone H3 lysine 4 by the trithorax group proteins ASH1 and TRX. Although we observed significant overlap between the distributions of KIS-L, ASH1, and TRX on polytene chromosomes, KIS-L did not bind methylated histone tails in vitro, and loss of TRX or ASH1 function did not alter the association of KIS-L with chromatin. By contrast, loss of kis function led to a dramatic reduction in the levels of TRX and ASH1 associated with chromatin and was accompanied by increased histone H3 lysine 27 methylation-a modification required for Polycomb group repression. A similar increase in H3 lysine 27 methylation was observed in ash1 and trx mutant larvae. Our findings suggest that KIS-L promotes early elongation and counteracts Polycomb group repression by recruiting the ASH1 and TRX histone methyltransferases to chromatin.

Neural cell adhesion molecule-180-mediated homophilic binding induces epidermal growth factor receptor (EGFR) down-regulation and uncouples the inhibitory function of EGFR in neurite outgrowth

DEFF Research Database (Denmark)

Povlsen, Gro Klitgaard; Berezin, Vladimir; Bock, Elisabeth

2008-01-01

The neural cell adhesion molecule (NCAM) plays important roles in neuronal development, regeneration, and synaptic plasticity. NCAM homophilic binding mediates cell adhesion and induces intracellular signals, in which the fibroblast growth factor receptor plays a prominent role. Recent studies...... this NCAM-180-induced EGFR down-regulation involves increased EGFR ubiquitination and lysosomal EGFR degradation. Furthermore, NCAM-180-mediated EGFR down-regulation requires NCAM homophilic binding and interactions of the cytoplasmic domain of NCAM-180 with intracellular interaction partners, but does...

Canonical TGF-β Signaling Negatively Regulates Neuronal Morphogenesis through TGIF/Smad Complex-Mediated CRMP2 Suppression.

Science.gov (United States)

Nakashima, Hideyuki; Tsujimura, Keita; Irie, Koichiro; Ishizu, Masataka; Pan, Miao; Kameda, Tomonori; Nakashima, Kinichi

2018-05-16

Functional neuronal connectivity requires proper neuronal morphogenesis and its dysregulation causes neurodevelopmental diseases. Transforming growth factor-β (TGF-β) family cytokines play pivotal roles in development, but little is known about their contribution to morphological development of neurons. Here we show that the Smad-dependent canonical signaling of TGF-β family cytokines negatively regulates neuronal morphogenesis during brain development. Mechanistically, activated Smads form a complex with transcriptional repressor TG-interacting factor (TGIF), and downregulate the expression of a neuronal polarity regulator, collapsin response mediator protein 2. We also demonstrate that TGF-β family signaling inhibits neurite elongation of human induced pluripotent stem cell-derived neurons. Furthermore, the expression of TGF-β receptor 1, Smad4, or TGIF, which have mutations found in patients with neurodevelopmental disorders, disrupted neuronal morphogenesis in both mouse (male and female) and human (female) neurons. Together, these findings suggest that the regulation of neuronal morphogenesis by an evolutionarily conserved function of TGF-β signaling is involved in the pathogenesis of neurodevelopmental diseases. SIGNIFICANCE STATEMENT Canonical transforming growth factor-β (TGF-β) signaling plays a crucial role in multiple organ development, including brain, and mutations in components of the signaling pathway associated with several human developmental disorders. In this study, we found that Smads/TG-interacting factor-dependent canonical TGF-β signaling regulates neuronal morphogenesis through the suppression of collapsin response mediator protein-2 (CRMP2) expression during brain development, and that function of this signaling is evolutionarily conserved in the mammalian brain. Mutations in canonical TGF-β signaling factors identified in patients with neurodevelopmental disorders disrupt the morphological development of neurons. Thus, our

The p75 neurotrophin receptor evades the endolysosomal route in neuronal cells, favouring multivesicular bodies specialised for exosomal release

Science.gov (United States)

Escudero, Claudia A.; Lazo, Oscal M.; Galleguillos, Carolina; Parraguez, Jose I.; Lopez-Verrilli, Maria A.; Cabeza, Carolina; Leon, Luisa; Saeed, Uzma; Retamal, Claudio; Gonzalez, Alfonso; Marzolo, Maria-Paz; Carter, Bruce D.; Court, Felipe A.; Bronfman, Francisca C.

2014-01-01

ABSTRACT The p75 neurotrophin receptor (p75, also known as NGFR) is a multifaceted signalling receptor that regulates neuronal physiology, including neurite outgrowth, and survival and death decisions. A key cellular aspect regulating neurotrophin signalling is the intracellular trafficking of their receptors; however, the post-endocytic trafficking of p75 is poorly defined. We used sympathetic neurons and rat PC12 cells to study the mechanism of internalisation and post-endocytic trafficking of p75. We found that p75 internalisation depended on the clathrin adaptor protein AP2 and on dynamin. More surprisingly, p75 evaded the lysosomal route at the level of the early endosome, instead accumulating in two different types of endosomes, Rab11-positive endosomes and multivesicular bodies (MVBs) positive for CD63, a marker of the exosomal pathway. Consistently, depolarisation by KCl induced the liberation of previously endocytosed full-length p75 into the extracellular medium in exosomes. Thus, p75 defines a subpopulation of MVBs that does not mature to lysosomes and is available for exosomal release by neuronal cells. PMID:24569882

Mental health of early adolescents from high-risk neighborhoods: the role of maternal HIV and other contextual, self-regulation, and family factors.

Science.gov (United States)

Mellins, Claude A; Brackis-Cott, Elizabeth; Dolezal, Curtis; Leu, Cheng Shiun; Valentin, Cidna; Meyer-Bahlburg, Heino F L

2008-01-01

To examine the effect of maternal HIV infection, as well as other individual, family, and contextual factors on the mental health of inner-city, ethnic minority early adolescents. Participants included 220 HIV-negative early adolescents (10-14 years) and their mothers, half of whom were HIV-infected. Individual interviews were conducted regarding youth depression, anxiety, externalizing and internalizing behaviour problems, as well as a range of correlates of youth mental health guided by a modified version of Social Action Theory, a theoretical model of behavioral health. Although the HIV status of mothers alone did not predict youth mental health, youth knowledge of mother's HIV infection and mother's overall health were associated with worse youth mental health outcomes, as were contextual, self-regulation, and family interaction factors from our theoretical model. There is a need for family-based mental health interventions for this population, particularly focusing on parent-child relationships, disclosure, and youth self-esteem.

Sex differences and emotion regulation: an event-related potential study.

Directory of Open Access Journals (Sweden)

Elyse K T Gardener

Full Text Available Difficulties in emotion regulation have been implicated as a potential mechanism underlying anxiety and mood disorders. It is possible that sex differences in emotion regulation may contribute towards the heightened female prevalence for these disorders. Previous fMRI studies of sex differences in emotion regulation have shown mixed results, possibly due to difficulties in discriminating the component processes of early emotional reactivity and emotion regulation. The present study used event-related potentials (ERPs to examine sex differences in N1 and N2 components (reflecting early emotional reactivity and P3 and LPP components (reflecting emotion regulation. N1, N2, P3, and LPP were recorded from 20 men and 23 women who were instructed to "increase," "decrease," and "maintain" their emotional response during passive viewing of negative images. Results indicated that women had significantly greater N1 and N2 amplitudes (reflecting early emotional reactivity to negative stimuli than men, supporting a female negativity bias. LPP amplitudes increased to the "increase" instruction, and women displayed greater LPP amplitudes than men to the "increase" instruction. There were no differences to the "decrease" instruction in women or men. These findings confirm predictions of the female negativity bias hypothesis and suggest that women have greater up-regulation of emotional responses to negative stimuli. This finding is highly significant in light of the female vulnerability for developing anxiety disorders.

Sex differences and emotion regulation: an event-related potential study.

Science.gov (United States)

Gardener, Elyse K T; Carr, Andrea R; Macgregor, Amy; Felmingham, Kim L

2013-01-01

Difficulties in emotion regulation have been implicated as a potential mechanism underlying anxiety and mood disorders. It is possible that sex differences in emotion regulation may contribute towards the heightened female prevalence for these disorders. Previous fMRI studies of sex differences in emotion regulation have shown mixed results, possibly due to difficulties in discriminating the component processes of early emotional reactivity and emotion regulation. The present study used event-related potentials (ERPs) to examine sex differences in N1 and N2 components (reflecting early emotional reactivity) and P3 and LPP components (reflecting emotion regulation). N1, N2, P3, and LPP were recorded from 20 men and 23 women who were instructed to "increase," "decrease," and "maintain" their emotional response during passive viewing of negative images. Results indicated that women had significantly greater N1 and N2 amplitudes (reflecting early emotional reactivity) to negative stimuli than men, supporting a female negativity bias. LPP amplitudes increased to the "increase" instruction, and women displayed greater LPP amplitudes than men to the "increase" instruction. There were no differences to the "decrease" instruction in women or men. These findings confirm predictions of the female negativity bias hypothesis and suggest that women have greater up-regulation of emotional responses to negative stimuli. This finding is highly significant in light of the female vulnerability for developing anxiety disorders.

The Canonical Immediate Early 3 Gene Product pIE611 of Mouse Cytomegalovirus Is Dispensable for Viral Replication but Mediates Transcriptional and Posttranscriptional Regulation of Viral Gene Products.

Science.gov (United States)

Rattay, Stephanie; Trilling, Mirko; Megger, Dominik A; Sitek, Barbara; Meyer, Helmut E; Hengel, Hartmut; Le-Trilling, Vu Thuy Khanh

2015-08-01

Transcription of mouse cytomegalovirus (MCMV) immediate early ie1 and ie3 is controlled by the major immediate early promoter/enhancer (MIEP) and requires differential splicing. Based on complete loss of genome replication of an MCMV mutant carrying a deletion of the ie3-specific exon 5, the multifunctional IE3 protein (611 amino acids; pIE611) is considered essential for viral replication. Our analysis of ie3 transcription resulted in the identification of novel ie3 isoforms derived from alternatively spliced ie3 transcripts. Construction of an IE3-hemagglutinin (IE3-HA) virus by insertion of an in-frame HA epitope sequence allowed detection of the IE3 isoforms in infected cells, verifying that the newly identified transcripts code for proteins. This prompted the construction of an MCMV mutant lacking ie611 but retaining the coding capacity for the newly identified isoforms ie453 and ie310. Using Δie611 MCMV, we demonstrated the dispensability of the canonical ie3 gene product pIE611 for viral replication. To determine the role of pIE611 for viral gene expression during MCMV infection in an unbiased global approach, we used label-free quantitative mass spectrometry to delineate pIE611-dependent changes of the MCMV proteome. Interestingly, further analysis revealed transcriptional as well as posttranscriptional regulation of MCMV gene products by pIE611. Cytomegaloviruses are pathogenic betaherpesviruses persisting in a lifelong latency from which reactivation can occur under conditions of immunosuppression, immunoimmaturity, or inflammation. The switch from latency to reactivation requires expression of immediate early genes. Therefore, understanding of immediate early gene regulation might add insights into viral pathogenesis. The mouse cytomegalovirus (MCMV) immediate early 3 protein (611 amino acids; pIE611) is considered essential for viral replication. The identification of novel protein isoforms derived from alternatively spliced ie3 transcripts prompted

Factors regulating early life history dispersal of Atlantic cod (Gadus morhua) from coastal Newfoundland.

Science.gov (United States)

Stanley, Ryan R E; deYoung, Brad; Snelgrove, Paul V R; Gregory, Robert S

2013-01-01

To understand coastal dispersal dynamics of Atlantic cod (Gadus morhua), we examined spatiotemporal egg and larval abundance patterns in coastal Newfoundland. In recent decades, Smith Sound, Trinity Bay has supported the largest known overwintering spawning aggregation of Atlantic cod in the region. We estimated spawning and dispersal characteristics for the Smith Sound-Trinity Bay system by fitting ichthyoplankton abundance data to environmentally-driven, simplified box models. Results show protracted spawning, with sharply increased egg production in early July, and limited dispersal from the Sound. The model for the entire spawning season indicates egg export from Smith Sound is 13%•day(-1) with a net mortality of 27%•day(-1). Eggs and larvae are consistently found in western Trinity Bay with little advection from the system. These patterns mirror particle tracking models that suggest residence times of 10-20 days, and circulation models indicating local gyres in Trinity Bay that act in concert with upwelling dynamics to retain eggs and larvae. Our results are among the first quantitative dispersal estimates from Smith Sound, linking this spawning stock to the adjacent coastal waters. These results illustrate the biophysical interplay regulating dispersal and connectivity originating from inshore spawning of coastal northwest Atlantic.

Factors regulating early life history dispersal of Atlantic cod (Gadus morhua from coastal Newfoundland.

Directory of Open Access Journals (Sweden)

Ryan R E Stanley

Full Text Available To understand coastal dispersal dynamics of Atlantic cod (Gadus morhua, we examined spatiotemporal egg and larval abundance patterns in coastal Newfoundland. In recent decades, Smith Sound, Trinity Bay has supported the largest known overwintering spawning aggregation of Atlantic cod in the region. We estimated spawning and dispersal characteristics for the Smith Sound-Trinity Bay system by fitting ichthyoplankton abundance data to environmentally-driven, simplified box models. Results show protracted spawning, with sharply increased egg production in early July, and limited dispersal from the Sound. The model for the entire spawning season indicates egg export from Smith Sound is 13%•day(-1 with a net mortality of 27%•day(-1. Eggs and larvae are consistently found in western Trinity Bay with little advection from the system. These patterns mirror particle tracking models that suggest residence times of 10-20 days, and circulation models indicating local gyres in Trinity Bay that act in concert with upwelling dynamics to retain eggs and larvae. Our results are among the first quantitative dispersal estimates from Smith Sound, linking this spawning stock to the adjacent coastal waters. These results illustrate the biophysical interplay regulating dispersal and connectivity originating from inshore spawning of coastal northwest Atlantic.

DELLA-induced early transcriptional changes during etiolated development in Arabidopsis thaliana.

Directory of Open Access Journals (Sweden)

Javier Gallego-Bartolomé

Full Text Available The hormones gibberellins (GAs control a wide variety of processes in plants, including stress and developmental responses. This task largely relies on the activity of the DELLA proteins, nuclear-localized transcriptional regulators that do not seem to have DNA binding capacity. The identification of early target genes of DELLA action is key not only to understand how GAs regulate physiological responses, but also to get clues about the molecular mechanisms by which DELLAs regulate gene expression. Here, we have investigated the global, early transcriptional response triggered by the Arabidopsis DELLA protein GAI during skotomorphogenesis, a developmental program tightly regulated by GAs. Our results show that the induction of GAI activity has an almost immediate effect on gene expression. Although this transcriptional regulation is largely mediated by the PIFs and HY5 transcription factors based on target meta-analysis, additional evidence points to other transcription factors that would be directly involved in DELLA regulation of gene expression. First, we have identified cis elements recognized by Dofs and type-B ARRs among the sequences enriched in the promoters of GAI targets; and second, an enrichment in additional cis elements appeared when this analysis was extended to a dataset of early targets of the DELLA protein RGA: CArG boxes, bound by MADS-box proteins, and the E-box CACATG that links the activity of DELLAs to circadian transcriptional regulation. Finally, Gene Ontology analysis highlights the impact of DELLA regulation upon the homeostasis of the GA, auxin, and ethylene pathways, as well as upon pre-existing transcriptional networks.

Neuropathology and Neurochemistry of Nonmotor Symptoms in Parkinson's Disease

Directory of Open Access Journals (Sweden)

Isidro Ferrer

2011-01-01

Full Text Available Parkinson disease (PD is no longer considered a complex motor disorder characterized by Parkinsonism but rather a systemic disease with variegated non-motor deficits and neurological symptoms, including impaired olfaction, autonomic failure, cognitive impairment, and psychiatric symptoms. Many of these alterations appear before or in parallel with motor deficits and then worsen with disease progression. Although there is a close relation between motor symptoms and the presence of Lewy bodies (LBs and neurites filled with abnormal -synuclein, other neurological alterations are independent of the amount of -synuclein inclusions in neurons and neurites, thereby indicating that different mechanisms probably converge in the degenerative process. Involvement of the cerebral cortex that may lead to altered behaviour and cognition are related to several convergent factors such as (a abnormal -synuclein and other proteins at the synapses, rather than LBs and neurites, (b impaired dopaminergic, noradrenergic, cholinergic and serotoninergic cortical innervation, and (c altered neuronal function resulting from reduced energy production and increased energy demands. These alterations appear at early stages of the disease and may precede by years the appearance of cell loss and cortical atrophy.

Geometrical Determinants of Neuronal Actin Waves.

Science.gov (United States)

Tomba, Caterina; Braïni, Céline; Bugnicourt, Ghislain; Cohen, Floriane; Friedrich, Benjamin M; Gov, Nir S; Villard, Catherine

2017-01-01

Hippocampal neurons produce in their early stages of growth propagative, actin-rich dynamical structures called actin waves. The directional motion of actin waves from the soma to the tip of neuronal extensions has been associated with net forward growth, and ultimately with the specification of neurites into axon and dendrites. Here, geometrical cues are used to control actin wave dynamics by constraining neurons on adhesive stripes of various widths. A key observable, the average time between the production of consecutive actin waves, or mean inter-wave interval (IWI), was identified. It scales with the neurite width, and more precisely with the width of the proximal segment close to the soma. In addition, the IWI is independent of the total number of neurites. These two results suggest a mechanistic model of actin wave production, by which the material conveyed by actin waves is assembled in the soma until it reaches the threshold leading to the initiation and propagation of a new actin wave. Based on these observations, we formulate a predictive theoretical description of actin wave-driven neuronal growth and polarization, which consistently accounts for different sets of experiments.

EARLY REGULATION IN CHILDREN WHO ARE LATER DIAGNOSED WITH AUTISM SPECTRUM DISORDER. A LONGITUDINAL STUDY WITHIN THE DANISH NATIONAL BIRTH COHORT.

Science.gov (United States)

Lemcke, Sanne; Parner, Erik T; Bjerrum, Merete; Thomsen, Per H; Lauritsen, Marlene B

2018-03-01

Studies have shown that children later diagnosed with autism spectrum disorders (ASD) in their first years of life might show symptoms in main developmental areas and that these signs might be sensed by the parents. The present study investigated in a large birth cohort if children later diagnosed with ASD had deviations at 6 and 18 months in areas such as the ability to self-regulate emotions, feeding, and sleeping. The study was based on prospective information collected from 76,322 mothers who participated in the Danish National Birth Cohort. When the children reached an average age of 11 years, 973 children with ASD and a control group of 300 children with intellectual disability (IDnoASD) were identified via Danish health registries. Associations were found between short periods of breast-feeding and the children later diagnosed with ASD and IDnoASD as well as associations at 18 months to deviations in regulation of emotions and activity. The similarities in these associations emphasize how difficult it is to distinguish between diagnoses early in life. © 2018 Michigan Association for Infant Mental Health.

Modulators of cytoskeletal reorganization in CA1 hippocampal neurons show increased expression in patients at mid-stage Alzheimer's disease.

Directory of Open Access Journals (Sweden)

Patricia F Kao

2010-10-01

Full Text Available During the progression of Alzheimer's disease (AD, hippocampal neurons undergo cytoskeletal reorganization, resulting in degenerative as well as regenerative changes. As neurofibrillary tangles form and dystrophic neurites appear, sprouting neuronal processes with growth cones emerge. Actin and tubulin are indispensable for normal neurite development and regenerative responses to injury and neurodegenerative stimuli. We have previously shown that actin capping protein beta2 subunit, Capzb2, binds tubulin and, in the presence of tau, affects microtubule polymerization necessary for neurite outgrowth and normal growth cone morphology. Accordingly, Capzb2 silencing in hippocampal neurons resulted in short, dystrophic neurites, seen in neurodegenerative diseases including AD. Here we demonstrate the statistically significant increase in the Capzb2 expression in the postmortem hippocampi in persons at mid-stage, Braak and Braak stage (BB III-IV, non-familial AD in comparison to controls. The dynamics of Capzb2 expression in progressive AD stages cannot be attributed to reactive astrocytosis. Moreover, the increased expression of Capzb2 mRNA in CA1 pyramidal neurons in AD BB III-IV is accompanied by an increased mRNA expression of brain derived neurotrophic factor (BDNF receptor tyrosine kinase B (TrkB, mediator of synaptic plasticity in hippocampal neurons. Thus, the up-regulation of Capzb2 and TrkB may reflect cytoskeletal reorganization and/or regenerative response occurring in hippocampal CA1 neurons at a specific stage of AD progression.

Distribution of precursor amyloid-β-protein messenger RNA in human cerebral cortex: relationship to neurofibrillary tangles and neuritic plaques

International Nuclear Information System (INIS)

Lewis, D.A.; Higgins, G.A.; Young, W.G.; Goldgaber, D.; Gajdusek, D.C.; Wilson, M.C.; Morrison, J.H.

1988-01-01

Neurofibrillary tangles (NFT) and neuritic plaques (NP), two neuropathological markers of Alzheimer disease, may both contain peptide fragments derived from the human amyloid β protein. However, the nature of the relationship between NFT and NP and the source of the amyloid β proteins found in each have remained unclear. The authors used in situ hybridization techniques to map the anatomical distribution of precursor amyloid-β-protein mRNA in the neocortex of brains from three subjects with no known neurologic disease and from five patients with Alzheimer disease. In brains from control subjects, positively hybridizing neurons were present in cortical regions and layers that contain a high density of neuropathological markers in Alzheimer disease, as well as in those loci that contain NP but few NFT. Quantitative analyses of in situ hybridization patterns within layers III and V of the superior frontal cortex revealed that the presence of high numbers of NFT in Alzheimer-diseased brains was associated with a decrease in the number of positively hybridizing neurons compared to controls and Alzheimer-diseased brains with few NFT. These findings suggest that the expression of precursor amyloid-β-protein mRNA may be a necessary but is clearly not a sufficient prerequisite for NFT formation. In addition, these results may indicate that the amyloid β protein, present in NP in a given region or layer of cortex, is not derived from the resident neuronal cell bodies that express the mRNA for the precursor protein

Commercial Banks and Capital Regulation in the Early 20th Century US

OpenAIRE

Gou, Michael

2017-01-01

My dissertation investigates the effect of capital requirements on commercial banks and the impact of commercial bank suspensions on the United States economy during the early 20th century. The first chapter examines the effect of capital requirements on bank stability. The early 20th century United States provides an opportunity to determine whether imposing capital requirements on commercial banks promotes banking stability in the long run. The structure of the national banking system fac...

Regulation of c-myc and c-fos mRNA levels by polyomavirus: distinct roles for the capsid protein VP1 and the viral early proteins

International Nuclear Information System (INIS)

Zullo, J.; Stiles, C.D.; Garcea, R.L.

1987-01-01

The levels of c-myc, c-fos, and JE mRNAs accumulate in a biphasic pattern following infection of quiescent BALB/c 3T3 mouse cells with polyomavirus. Maximal levels of c-myc and c-fos mRNAs were seen within 1 hr and were nearly undetectable at 6 hr after infection. At 12 hr after infection mRNA levels were again maximal and remained elevated thereafter. Empty virions (capsids) and recombinant VP 1 protein, purified from Escherichia coli, induced the early but not the late phase of mRNA accumulation. Virions, capsids, and recombinant VP 1 protein stimulated [ 3 H]thymidine nuclear labeling and c-myc mRNA accumulation in a dose-responsive manner paralleling their affinity for the cell receptor for polyoma. The second phase of mRNA accumulation is regulated by the viral early gene products, as shown by polyomavirus early gene mutants and by a transfected cell line (336a) expressing middle tumor antigen upon glucocorticoid addition. These results suggest that polyomavirus interacts with the cell membrane at the onset of infection to increase the levels of mRNA for the cellular genes associated with cell competence for DNA replication, and subsequently these levels are maintained by the action of the early viral proteins

Daidzein induces neuritogenesis in DRG neuronal cultures

Directory of Open Access Journals (Sweden)

Yang Shih-Hung

2012-08-01

Full Text Available Absract Background Daidzein, a phytoestrogen found in isoflavone, is known to exert neurotrophic and neuroprotective effects on the nervous system. Using primary rat dorsal root ganglion (DRG neuronal cultures, we have examined the potential neurite outgrowth effect of daidzein. Methods Dissociated dorsal root ganglia (DRG cultures were used to study the signaling mechanism of daidzein-induced neuritogenesis by immunocytochemistry and Western blotting. Results In response to daidzein treatment, DRG neurons showed a significant increase in total neurite length and in tip number per neuron. The neuritogenic effect of daidzein was significantly hampered by specific blockers for Src, protein kinase C delta (PKCδ and mitogen-activated protein kinase/extracellular signal-regulated kinase kinases (MEK/ERK, but not by those for estrogen receptor (ER. Moreover, daidzein induced phosphorylation of Src, PKCδ and ERK. The activation of PKCδ by daidzein was attenuated in the presence of a Src kinase inhibitor, and that of ERK by daidzein was diminished in the presence of either a Src or PKCδ inhibitor. Conclusion Daidzein may stimulate neurite outgrowth of DRG neurons depending on Src kinase, PKCδ and ERK signaling pathway.

Bioactivity-guided fractionation identifies amygdalin as a potent neurotrophic agent from herbal medicine Semen Persicae extract.

Science.gov (United States)

Yang, Chuanbin; Zhao, Jia; Cheng, Yuanyuan; Li, Xuechen; Rong, Jianhui

2014-01-01

Herbal medicine Semen Persicae is widely used to treat blood stasis in Chinese medicine and other oriental folk medicines. Although little is known about the effects of Semen Persicae and its active compounds on neuron differentiation, our pilot study showed that Semen Persicae extract promoted neurite outgrowth in rat dopaminergic PC12 cells. In the present study, we developed a bioactivity-guided fractionation procedure for the characterization of the neurotrophic activity of Semen Persicae extract. The resultant fractions were assayed for neurite outgrowth in PC12 cells based on microscopic assessment. Through liquid-liquid extraction and reverse phase HPLC separation, a botanical glycoside amygdalin was isolated as the active compound responsible for the neurotrophic activity of Semen Persicae extract. Moreover, we found that amygdalin rapidly induced the activation of extracellular-signal-regulated kinase 1/2 (ERK1/2). A specific ERK1/2 inhibitor PD98059 attenuated the stimulatory effect of amygdalin on neurite outgrowth. Taken together, amygdalin was identified as a potent neurotrophic agent from Semen Persicae extract through a bioactivity-guided fractional procedure. The neurotrophic activity of amygdalin may be mediated by the activation of ERK1/2 pathway.

Bioactivity-Guided Fractionation Identifies Amygdalin as a Potent Neurotrophic Agent from Herbal Medicine Semen Persicae Extract

Directory of Open Access Journals (Sweden)

Chuanbin Yang

2014-01-01

Full Text Available Herbal medicine Semen Persicae is widely used to treat blood stasis in Chinese medicine and other oriental folk medicines. Although little is known about the effects of Semen Persicae and its active compounds on neuron differentiation, our pilot study showed that Semen Persicae extract promoted neurite outgrowth in rat dopaminergic PC12 cells. In the present study, we developed a bioactivity-guided fractionation procedure for the characterization of the neurotrophic activity of Semen Persicae extract. The resultant fractions were assayed for neurite outgrowth in PC12 cells based on microscopic assessment. Through liquid-liquid extraction and reverse phase HPLC separation, a botanical glycoside amygdalin was isolated as the active compound responsible for the neurotrophic activity of Semen Persicae extract. Moreover, we found that amygdalin rapidly induced the activation of extracellular-signal-regulated kinase 1/2 (ERK1/2. A specific ERK1/2 inhibitor PD98059 attenuated the stimulatory effect of amygdalin on neurite outgrowth. Taken together, amygdalin was identified as a potent neurotrophic agent from Semen Persicae extract through a bioactivity-guided fractional procedure. The neurotrophic activity of amygdalin may be mediated by the activation of ERK1/2 pathway.

Early life treatment with vancomycin reduces diabetes incidence in NOD mice

DEFF Research Database (Denmark)

Hansen, Camilla Hartmann Friis; Nielsen, Dennis Sandris; Vogensen, Finn Kvist

Type 1 diabetes (T1D) results from an uncontrolled T cell mediated destruction of the insulin-producing beta-cells in the pancreas. Causal factors include a combination of genetics, early life incidents and the food we eat. The involved adaptive immune response can be down regulated by a regulato...... of the mechanisms regulating intestinal immune homeostasis toward a proinflammatory mucosal environment.......Type 1 diabetes (T1D) results from an uncontrolled T cell mediated destruction of the insulin-producing beta-cells in the pancreas. Causal factors include a combination of genetics, early life incidents and the food we eat. The involved adaptive immune response can be down regulated by a regulatory...... immune response and a fine-tuned balance between these immunological components is crucial for characteristics of the disease, such as severity, onset time and recovery. The balance between the regulatory and the adaptive immune response is heavily influenced by early life bacterial stimulation...

Biotechnology regulation: limiting or contributing to biotech development?

DEFF Research Database (Denmark)

Hansen, Anne Grethe

2001-01-01

to the European arena, their role and extension are still an issue. In this paper, the often anticipated innovation-inhibiting effects of regulation are questioned by giving an account of regulations and debates in Denmark. An account which includes the shifting positions of industry, the research community......Modern biotechnology has been characterized by being surrounded by scientific and public debate and by interest conflicts. An early Danish debate and regulation has been criticized for inhibiting or retarding development and thus growth. Though much regulation and debate have been transferred...

Sex Differences and Emotion Regulation: An Event-Related Potential Study

OpenAIRE

Gardener, Elyse K. T.; Carr, Andrea R.; MacGregor, Amy; Felmingham, Kim L.

2013-01-01

Difficulties in emotion regulation have been implicated as a potential mechanism underlying anxiety and mood disorders. It is possible that sex differences in emotion regulation may contribute towards the heightened female prevalence for these disorders. Previous fMRI studies of sex differences in emotion regulation have shown mixed results, possibly due to difficulties in discriminating the component processes of early emotional reactivity and emotion regulation. The present study used event...

Effective management of regulator RI/FS comments

International Nuclear Information System (INIS)

Wolinsky, S.M.; Lojek, D.; George, R.D.; Houser, S.M.; Strimbu, M.J.

1995-01-01

This paper describes a successful strategy that facilitates regulatory approval of CERCLA documents required by compliance agreement and CERCLA, based on the experience of Operable Unit 1, Waste Storage Area, of the Fernald Environmental Management Project (FEMP). This strategy, which has become the site standard at the FEMP, was instrumental in obtaining regulator approval of the OU1 RI and FS, and early approval of the Record of Decision during a very tight compliance agreement-driven schedule. This strategy can be applied at any DOE Superfund site, especially where there is need to recover lost schedule, an incentive to meet milestones early, a need to improve the relationship between the DOE and the regulators, or where the regulatory agencies have historically provided a large volume of comments on CERCLA documents. The strategy focuses on early identification and resolution of issues relating to draft RI/FS documents, as raised in regulatory agency review comments. This pro-active strategy has the potential for schedule and cost savings, as well as for improved communication between DOE and the regulators. The strategy includes preparation of a separate comment response document, integration of comment responses with RI/FS documents, development of a database of agency comments and their resolution, and sharing lessons learned with preparers of subsequent RI/FS documents. The paper provides background on the FEMP and describes the FEMP comment response strategy; DOE and regulator interface; the Sitewide Comment Database; networked electronic file management; the process for classifying, analyzing, and responding to comments; integration with base RI/FS documents; and a conclusion

Effective management of regulator RI/FS comments

Energy Technology Data Exchange (ETDEWEB)

Wolinsky, S.M.; Lojek, D.; George, R.D.; Houser, S.M.; Strimbu, M.J.

1995-12-31

This paper describes a successful strategy that facilitates regulatory approval of CERCLA documents required by compliance agreement and CERCLA, based on the experience of Operable Unit 1, Waste Storage Area, of the Fernald Environmental Management Project (FEMP). This strategy, which has become the site standard at the FEMP, was instrumental in obtaining regulator approval of the OU1 RI and FS, and early approval of the Record of Decision during a very tight compliance agreement-driven schedule. This strategy can be applied at any DOE Superfund site, especially where there is need to recover lost schedule, an incentive to meet milestones early, a need to improve the relationship between the DOE and the regulators, or where the regulatory agencies have historically provided a large volume of comments on CERCLA documents. The strategy focuses on early identification and resolution of issues relating to draft RI/FS documents, as raised in regulatory agency review comments. This pro-active strategy has the potential for schedule and cost savings, as well as for improved communication between DOE and the regulators. The strategy includes preparation of a separate comment response document, integration of comment responses with RI/FS documents, development of a database of agency comments and their resolution, and sharing lessons learned with preparers of subsequent RI/FS documents. The paper provides background on the FEMP and describes the FEMP comment response strategy; DOE and regulator interface; the Sitewide Comment Database; networked electronic file management; the process for classifying, analyzing, and responding to comments; integration with base RI/FS documents; and a conclusion.

Quality Early Education and Child Care From Birth to Kindergarten.

Science.gov (United States)

Donoghue, Elaine A

2017-08-01

High-quality early education and child care for young children improves physical and cognitive outcomes for the children and can result in enhanced school readiness. Preschool education can be viewed as an investment (especially for at-risk children), and studies show a positive return on that investment. Barriers to high-quality early childhood education include inadequate funding and staff education as well as variable regulation and enforcement. Steps that have been taken to improve the quality of early education and child care include creating multidisciplinary, evidence-based child care practice standards; establishing state quality rating and improvement systems; improving federal and state regulations; providing child care health consultation; as well as initiating other innovative partnerships. Pediatricians have a role in promoting quality early education and child care for all children not only in the medical home but also at the community, state, and national levels. Copyright © 2017 by the American Academy of Pediatrics.

Activity-associated miRNA are packaged in Map1b-enriched exosomes released from depolarized neurons.

Science.gov (United States)

Goldie, Belinda J; Dun, Matthew D; Lin, Minjie; Smith, Nathan D; Verrills, Nicole M; Dayas, Christopher V; Cairns, Murray J

2014-08-01

Rapid input-restricted change in gene expression is an important aspect of synaptic plasticity requiring complex mechanisms of post-transcriptional mRNA trafficking and regulation. Small non-coding miRNA are uniquely poised to support these functions by providing a nucleic-acid-based specificity component for universal-sequence-dependent RNA binding complexes. We investigated the subcellular distribution of these molecules in resting and potassium chloride depolarized human neuroblasts, and found both selective enrichment and depletion in neurites. Depolarization was associated with a neurite-restricted decrease in miRNA expression; a subset of these molecules was recovered from the depolarization medium in nuclease resistant extracellular exosomes. These vesicles were enriched with primate specific miRNA and the synaptic-plasticity-associated protein MAP1b. These findings further support a role for miRNA as neural plasticity regulators, as they are compartmentalized in neurons and undergo activity-associated redistribution or release into the extracellular matrix. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

An Fgf-Shh signaling hierarchy regulates early specification of the zebrafish skull.

Science.gov (United States)

McCarthy, Neil; Sidik, Alfire; Bertrand, Julien Y; Eberhart, Johann K

2016-07-15

The neurocranium generates most of the craniofacial skeleton and consists of prechordal and postchordal regions. Although development of the prechordal is well studied, little is known of the postchordal region. Here we characterize a signaling hierarchy necessary for postchordal neurocranial development involving Fibroblast growth factor (Fgf) signaling for early specification of mesodermally-derived progenitor cells. The expression of hyaluron synthetase 2 (has2) in the cephalic mesoderm requires Fgf signaling and Has2 function, in turn, is required for postchordal neurocranial development. While Hedgehog (Hh)-deficient embryos also lack a postchordal neurocranium, this appears primarily due to a later defect in chondrocyte differentiation. Inhibitor studies demonstrate that postchordal neurocranial development requires early Fgf and later Hh signaling. Collectively, our results provide a mechanistic understanding of early postchordal neurocranial development and demonstrate a hierarchy of signaling between Fgf and Hh in the development of this structure. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Do infants fed directly from the breast have improved appetite regulation and slower growth during early childhood compared with infants fed from a bottle?

Directory of Open Access Journals (Sweden)

Fisher Jennifer O

2011-08-01

Full Text Available Abstract Background Behavioral mechanisms that contribute to the association between breastfeeding and reduced obesity risk are poorly understood. The purpose of this study was to evaluate the hypothesis that feeding human milk from the breast (direct breastfeeding has a more optimal association with subsequent child appetite regulation behaviors and growth, when compared to bottle-feeding. Methods Children (n = 109 aged 3- to 6- years were retrospectively classified as directly breastfed (fed exclusively at the breast, bottle-fed human milk, or bottle-fed formula in the first three months of life. Young children's appetite regulation was examined by measuring three constructs (satiety response, food responsiveness, enjoyment of food associated with obesity risk, using the Child Eating Behavior Questionnaire. Multinomial logistic regression analyses were used to test whether children bottle-fed either human milk or formula had reduced odds of high satiety and increased odds of high food responsiveness and high enjoyment of food compared to children fed directly from the breast. Current child weight status and growth trends from 6-36 months were also examined for their relation to direct breastfeeding and appetite regulation behaviors in early childhood. Results Children fed human milk in a bottle were 67% less likely to have high satiety responsiveness compared to directly breastfed children, after controlling for child age, child weight status, maternal race/ethnicity, and maternal education. There was no association of bottle-feeding (either human milk or formula with young children's food responsiveness and enjoyment of food. There was neither an association of direct breastfeeding with current child weight status, nor was there a clear difference between directly breastfed and bottle-fed children in growth trajectories from 6- to 36-months. More rapid infant changes in weight-for-age score were associated with lower satiety responsiveness

Nav2 is necessary for cranial nerve development and blood pressure regulation

OpenAIRE

McNeill, Elizabeth M; Roos, Kenneth P; Moechars, Dieder; Clagett-Dame, Margaret

2010-01-01

Abstract Background All-trans retinoic acid (atRA) is required for nervous system development, including the developing hindbrain region. Neuron navigator 2 (Nav2) was first identified as an atRA-responsive gene in human neuroblastoma cells (retinoic acid-induced in neuroblastoma 1, Rainb1), and is required for atRA-mediated neurite outgrowth. In this paper, we explore the importance of Nav2 in nervous system development and function in vivo. Results Nav2 hypomorphic homozygous mutants show d...

Application of sequence stratigraphy to carbonate reservoir prediction, Early Palaeozoic eastern Warburton basin, South Australia

Energy Technology Data Exchange (ETDEWEB)

Xiaowen S.; Stuart, W.J.

1996-12-31

The Early Palaeozoic Warburton Basin underlies the gas and oil producing Cooper and Eromanga Basins. Postdepositional tectonism created high potential fracture porosities, complicating the stratigraphy and making reservoir prediction difficult. Sequence stratigraphy integrating core, cuttings, well-log, seismic and biostratigraphic data has recognized a carbonate-dominated to mixed carbonate/siliciclastic supersequence comprising several depositional sequences. Biostratigraphy based on trilobites and conodonts ensures reliable well and seismic correlations across structurally complex areas. Lithofacies interpretation indicates sedimentary environments ranging from carbonate inner shelf, peritidal, shelf edge, deep outer shelf and slope to basin. Log facies show gradually upward shallowing trends or abrupt changes indicating possible sequence boundaries. With essential depositional models and sequence analysis from well data, seismic facies suggest general reflection configurations including parallel-continuous layered patterns indicating uniform neuritic shelf, and mounded structures suggesting carbonate build-ups and pre-existing volcanic relief. Seismic stratigraphy also reveals inclined slope and onlapping margins of a possibly isolated platform geometry. The potential reservoirs are dolomitized carbonates containing oomoldic, vuggy, intercrystalline and fracture porosities in lowstand systems tracts either on carbonate mounds and shelf crests or below shelf edge. The source rock is a deep basinal argillaceous mudstone, and the seal is fine-grained siltstone/shale of the transgressive system tract.

Application of sequence stratigraphy to carbonate reservoir prediction, Early Palaeozoic eastern Warburton basin, South Australia

Energy Technology Data Exchange (ETDEWEB)

Xiaowen S.; Stuart, W.J.

1996-01-01

The Early Palaeozoic Warburton Basin underlies the gas and oil producing Cooper and Eromanga Basins. Postdepositional tectonism created high potential fracture porosities, complicating the stratigraphy and making reservoir prediction difficult. Sequence stratigraphy integrating core, cuttings, well-log, seismic and biostratigraphic data has recognized a carbonate-dominated to mixed carbonate/siliciclastic supersequence comprising several depositional sequences. Biostratigraphy based on trilobites and conodonts ensures reliable well and seismic correlations across structurally complex areas. Lithofacies interpretation indicates sedimentary environments ranging from carbonate inner shelf, peritidal, shelf edge, deep outer shelf and slope to basin. Log facies show gradually upward shallowing trends or abrupt changes indicating possible sequence boundaries. With essential depositional models and sequence analysis from well data, seismic facies suggest general reflection configurations including parallel-continuous layered patterns indicating uniform neuritic shelf, and mounded structures suggesting carbonate build-ups and pre-existing volcanic relief. Seismic stratigraphy also reveals inclined slope and onlapping margins of a possibly isolated platform geometry. The potential reservoirs are dolomitized carbonates containing oomoldic, vuggy, intercrystalline and fracture porosities in lowstand systems tracts either on carbonate mounds and shelf crests or below shelf edge. The source rock is a deep basinal argillaceous mudstone, and the seal is fine-grained siltstone/shale of the transgressive system tract.

Early gene Broad complex plays a key role in regulating the immune response triggered by ecdysone in the Malpighian tubules of Drosophila melanogaster.

Science.gov (United States)

Verma, Puja; Tapadia, Madhu G

2015-08-01

In insects, humoral response to injury is accomplished by the production of antimicrobial peptides (AMPs) which are secreted in the hemolymph to eliminate the pathogen. Drosophila Malpighian tubules (MTs), however, are unique immune organs that show constitutive expression of AMPs even in unchallenged conditions and the onset of immune response is developmental stage dependent. Earlier reports have shown ecdysone positively regulates immune response after pathogenic challenge however, a robust response requires prior potentiation by the hormone. Here we provide evidence to show that MTs do not require prior potentiation with ecdysone hormone for expression of AMPs and they respond to ecdysone very fast even without immune challenge, although the different AMPs Diptericin, Cecropin, Attacin, Drosocin show differential expression in response to ecdysone. We show that early gene Broad complex (BR-C) could be regulating the IMD pathway by activating Relish and physically interacting with it to activate AMPs expression. BR-C depletion from Malpighian tubules renders the flies susceptible to infection. We also show that in MTs ecdysone signaling is transduced by EcR-B1 and B2. In the absence of ecdysone signaling the IMD pathway associated genes are down regulated and activation and translocation of transcription factor Relish is also affected. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dynamic Transcriptional Regulation of Fis in Salmonella During the Exponential Phase.

Science.gov (United States)

Wang, Hui; Wang, Lei; Li, Ping; Hu, Yilang; Zhang, Wei; Tang, Bo

2015-12-01

Fis is one of the most important global regulators and has attracted extensive research attention. Many studies have focused on comparing the Fis global regulatory networks for exploring Fis function during different growth stages, such as the exponential and stationary stages. Although the Fis protein in bacteria is mainly expressed in the exponential phase, the dynamic transcriptional regulation of Fis during the exponential phase remains poorly understood. To address this question, we used RNA-seq technology to identify the Fis-regulated genes in the S. enterica serovar Typhimurium during the early exponential phase, and qRT-PCR was performed to validate the transcriptional data. A total of 1495 Fis-regulated genes were successfully identified, including 987 Fis-repressed genes and 508 Fis-activated genes. Comparing the results of this study with those of our previous study, we found that the transcriptional regulation of Fis was diverse during the early- and mid-exponential phases. The results also showed that the strong positive regulation of Fis on Salmonella pathogenicity island genes in the mid-exponential phase transitioned into insignificant effect in the early exponential phase. To validate these results, we performed a cell infection assay and found that Δfis only exhibited a 1.49-fold decreased capacity compared with the LT2 wild-type strain, indicating a large difference from the 6.31-fold decrease observed in the mid-exponential phase. Our results provide strong evidence for a need to thoroughly understand the dynamic transcriptional regulation of Fis in Salmonella during the exponential phase.

A growing field: The regulation of axonal regeneration by Wnt signaling.

Science.gov (United States)

Garcia, Armando L; Udeh, Adanna; Kalahasty, Karthik; Hackam, Abigail S

2018-01-01

The canonical Wnt/β-catenin pathway is a highly conserved signaling cascade that plays critical roles during embryogenesis. Wnt ligands regulate axonal extension, growth cone guidance and synaptogenesis throughout the developing central nervous system (CNS). Recently, studies in mammalian and fish model systems have demonstrated that Wnt/β-catenin signaling also promotes axonal regeneration in the adult optic nerve and spinal cord after injury, raising the possibility that Wnt could be developed as a therapeutic strategy. In this review, we summarize experimental evidence that reveals novel roles for Wnt signaling in the injured CNS, and discuss possible mechanisms by which Wnt ligands could overcome molecular barriers inhibiting axonal growth to promote regeneration. A central challenge in the neuroscience field is developing therapeutic strategies that induce robust axonal regeneration. Although adult axons have the capacity to respond to axonal guidance molecules after injury, there are several major obstacles for axonal growth, including extensive neuronal death, glial scars at the injury site, and lack of axonal guidance signals. Research in rodents demonstrated that activation of Wnt/β-catenin signaling in retinal neurons and radial glia induced neuronal survival and axonal growth, but that activation within reactive glia at the injury site promoted proliferation and glial scar formation. Studies in zebrafish spinal cord injury models confirm an axonal regenerative role for Wnt/β-catenin signaling and identified the cell types responsible. Additionally, in vitro and in vivo studies demonstrated that Wnt induces axonal and neurite growth through transcription-dependent effects of its central mediator β-catenin, potentially by inducing regeneration-promoting genes. Canonical Wnt signaling may also function through transcription-independent interactions of β-catenin with cytoskeletal elements, which could stabilize growing axons and control growth cone

Infant Sleep Predicts Attention Regulation and Behavior Problems at 3-4 Years of Age.

Science.gov (United States)

Sadeh, Avi; De Marcas, Gali; Guri, Yael; Berger, Andrea; Tikotzky, Liat; Bar-Haim, Yair

2015-01-01

This longitudinal study assessed the role of early sleep patterns in predicting attention regulation and behavior problems. Sleep of 43 infants was assessed using actigraphy at 12 months of age and then reassessed when the children were 3-4 years old. During this follow-up, their attention regulation and behavior problems were also assessed using a computerized test and parental reports. Lower quality of sleep in infancy significantly predicted compromised attention regulation and behavior problems. These findings underscore the need to identify and treat early sleep problems.

Up-regulation of DRP-3 long isoform during the induction of neural progenitor cells by glutamate treatment in the ex vivo rat retina

Energy Technology Data Exchange (ETDEWEB)

Tokuda, Kazuhiro, E-mail: r502um@yamaguchi-u.ac.jp [Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi (Japan); Department of Biochemistry and Functional Proteomics, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi (Japan); Kuramitsu, Yasuhiro; Byron, Baron; Kitagawa, Takao [Department of Biochemistry and Functional Proteomics, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi (Japan); Tokuda, Nobuko [Faculty of Health Sciences, Yamaguchi University Graduate School of Medicine, Ube (Japan); Kobayashi, Daiki; Nagayama, Megumi; Araki, Norie [Department of Tumor Genetics and Biology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto (Japan); Sonoda, Koh-Hei [Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi (Japan); Nakamura, Kazuyuki [Department of Biochemistry and Functional Proteomics, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi (Japan)

2015-08-07

Glutamate has been shown to induce neural progenitor cells in the adult vertebrate retina. However, protein dynamics during progenitor cell induction by glutamate are not fully understood. To identify specific proteins involved in the process, we employed two-dimensional electrophoresis-based proteomics on glutamate untreated and treated retinal ex vivo sections. Rat retinal tissues were incubated with 1 mM glutamate for 1 h, followed by incubation in glutamate-free media for a total of 24 h. Consistent with prior reports, it was found that mitotic cells appeared in the outer nuclear layer without any histological damage. Immunohistological evaluations and immunoblotting confirmed the emergence of neuronal progenitor cells in the mature retina treated with glutamate. Proteomic analysis revealed the up-regulation of dihydropyrimidinase-related protein 3 (DRP-3), DRP-2 and stress-induced-phosphoprotein 1 (STIP1) during neural progenitor cell induction by glutamate. Moreover, mRNA expression of DRP-3, especially, its long isoform, robustly increased in the treated retina compared to that in the untreated retina. These results may indicate that glutamate induces neural progenitor cells in the mature rat retina by up-regulating the proteins which mediate cell mitosis and neurite growth. - Highlights: • Glutamate induced neuronal progenitor cells in the mature rat retina. • Proteomic analysis revealed the up-regulation of DRP-3, DRP-2 and STIP1. • mRNA expression of DRP-3, especially, its long isoform, robustly increased.

External-environmental and internal-health early life predictors of adolescent development.

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Hartman, Sarah; Li, Zhi; Nettle, Daniel; Belsky, Jay

2017-12-01

A wealth of evidence documents associations between various aspects of the rearing environment and later development. Two evolutionary-inspired models advance explanations for why and how such early experiences shape later functioning: (a) the external-prediction model, which highlights the role of the early environment (e.g., parenting) in regulating children's development, and (b) the internal-prediction model, which emphasizes internal state (i.e., health) as the critical regulator. Thus, by using data from the NICHD Study of Early Child Care and Youth Development, the current project draws from both models by investigating whether the effect of the early environment on later adolescent functioning is subject to an indirect effect by internal-health variables. Results showed a significant indirect effect of internal health on the relation between the early environment and adolescent behavior. Specifically, early environmental adversity during the first 5 years of life predicted lower quality health during childhood, which then led to problematic adolescent functioning and earlier age of menarche for girls. In addition, for girls, early adversity predicted lower quality health that forecasted earlier age of menarche leading to increased adolescent risk taking. The discussion highlights the importance of integrating both internal and external models to further understand the developmental processes that effect adolescent behavior.

The early activation marker CD69 regulates the expression of chemokines and CD4 T cell accumulation in intestine.

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Katarina Radulovic

Full Text Available Migration of naïve and activated lymphocytes is regulated by the expression of various molecules such as chemokine receptors and ligands. CD69, the early activation marker of C-type lectin domain family, is also shown to regulate the lymphocyte migration by affecting their egress from the thymus and secondary lymphoid organs. Here, we aimed to investigate the role of CD69 in accumulation of CD4 T cells in intestine using murine models of inflammatory bowel disease. We found that genetic deletion of CD69 in mice increases the expression of the chemokines CCL-1, CXCL-10 and CCL-19 in CD4(+ T cells and/or CD4(- cells. Efficient in vitro migration of CD69-deficient CD4 T cells toward the chemokine stimuli was the result of increased expression and/or affinity of chemokine receptors. In vivo CD69(-/- CD4 T cells accumulate in the intestine in higher numbers than B6 CD4 T cells as observed in competitive homing assay, dextran sodium sulphate (DSS-induced colitis and antigen-specific transfer colitis. In DSS colitis CD69(-/- CD4 T cell accumulation in colonic lamina propria (cLP was associated with increased expression of CCL-1, CXCL-10 and CCL-19 genes. Furthermore, treatment of DSS-administrated CD69(-/- mice with the mixture of CCL-1, CXCL-10 and CCL-19 neutralizing Abs significantly decreased the histopathological signs of colitis. Transfer of OT-II×CD69(-/- CD45RB(high CD4 T cells into RAG(-/- hosts induced CD4 T cell accumulation in cLP. This study showed CD69 as negative regulator of inflammatory responses in intestine as it decreases the expression of chemotactic receptors and ligands and reduces the accumulation of CD4 T cells in cLP during colitis.

The CD147/MMP-2 signaling pathway may regulate early stage cardiac remodelling in spontaneously hypertensive rats.

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Li, Bowei; Zhou, Wanxing; Yang, Xiaorong; Zhou, Yuliang; Tan, Yongjing; Yuan, Congcong; Song, Yulan; Chen, Xiao; Zhang, Wei

2016-11-01

Previous studies have reported that decreased matrix metalloproteinase-2 (MMP-2) is associated with early stage (age 8-16 weeks) ventricular remodelling in spontaneously hypertensive rats (SHR). We hypothesized that inhibited CD147/MMP-2 signalling might down-regulate MMP-2 expression and augment remodelling in spontaneously hypertensive rats. Twenty-nine male SHR (8 weeks) were randomly assigned to SHR, CD147, and CD147+DOX groups. The control group included eight age-matched WKY rats. CD147 and CD147+DOX groups received recombinant human CD147 (600 ng/kg in 1.5 mL saline, weekly). The SHR and WKY groups received the vehicle. The CD147+DOX group also received doxycycline, an inhibitor of MMPs (daily, 30 mg/kg in 1.5 mL saline, iG). On day 56 echocardiography and left ventricular mass index (LVWI) measurements were collected and histological sections were stained for cell and collagen content. Myocardium MMP-2, TIMP-1, CD147, and collagens types I and III were estimated by western blot. CD147 and the ratio of MMP-2/TIMP-1 were lower in SHR than WKY rats (PCD147 rats showed CD147, MMP-2 and MMP-2/TIMP-1 were increased (PCD147 levels did not differ between CD147+DOX and CD147 groups, CVF, collagens type I and III and partial fiber breaks were more abundant in CD147+DOX (PCD147/MMP-2 pathway was associated with early stage cardiac remodelling, and CD147 supplementation may attenuate this response. © 2016 John Wiley & Sons Australia, Ltd.

Peer victimization and peer rejection during early childhood

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Godleski, Stephanie A.; Kamper, Kimberly E.; Ostrov, Jamie M.; Hart, Emily J.; Blakely-McClure, Sarah J.

2014-01-01

Objective The development and course of the subtypes of peer victimization is a relatively understudied topic despite the association of victimization with important developmental and clinical outcomes. Moreover, understanding potential predictors, such as peer rejection and emotion regulation, in early childhood may be especially important to elucidate possible bi-directional pathways between relational and physical victimization and rejection. The current study (N = 97) was designed to explore several gaps and limitations in the peer victimization and peer rejection literature. In particular, the prospective associations between relational and physical victimization and peer rejection over the course of 3.5 months during early childhood (i.e., 3- to 5- years-old) were investigated in an integrated model. Method The study consisted of 97 (42 girls) preschool children recruited from four early childhood schools in the northeast of the US. Using observations, research assistant report and teacher report, relational and physical aggression, relational and physical victimization, peer rejection, and emotion regulation were measured in a short-term longitudinal study. Path analyses were conducted to test the overall hypothesized model. Results Peer rejection was found to predict increases in relational victimization. In addition, emotion regulation was found to predict decreases in peer rejection and physical victimization. Conclusions Implications for research and practice are discussed, including teaching coping strategies for peer rejection and emotional distress. PMID:25133659

Semaphorin7A and its receptors: pleiotropic regulators of immune cell function, bone homeostasis, and neural development.

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Jongbloets, Bart C; Ramakers, Geert M J; Pasterkamp, R Jeroen

2013-03-01

Semaphorins form a large, evolutionary conserved family of cellular guidance signals. The semaphorin family contains several secreted and transmembrane proteins, but only one GPI-anchored member, Semaphorin7A (Sema7A). Although originally identified in immune cells, as CDw108, Sema7A displays widespread expression outside the immune system. It is therefore not surprising that accumulating evidence supports roles for this protein in a wide variety of biological processes in different organ systems and in disease. Well-characterized biological effects of Sema7A include those during bone and immune cell regulation, neuron migration and neurite growth. These effects are mediated by two receptors, plexinC1 and integrins. However, most of what is known today about Sema7A signaling concerns Sema7A-integrin interactions. Here, we review our current knowledge of Sema7A function and signaling in different organ systems, highlighting commonalities between the cellular effects and signaling pathways activated by Sema7A in different cell types. Furthermore, we discuss a potential role for Sema7A in disease and provide directions for further research. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sphingosine-1-Phosphate and the S1P3 Receptor Initiate Neuronal Retraction via RhoA/ROCK Associated with CRMP2 Phosphorylation

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Quarta, Serena; Camprubí-Robles, Maria; Schweigreiter, Rüdiger; Matusica, Dusan; Haberberger, Rainer V.; Proia, Richard L.; Bandtlow, Christine E.; Ferrer-Montiel, Antonio; Kress, Michaela

2017-01-01

The bioactive lipid sphingosine-1-phosphate (S1P) is an important regulator in the nervous system. Here, we explored the role of S1P and its receptors in vitro and in preclinical models of peripheral nerve regeneration. Adult sensory neurons and motor neuron-like cells were exposed to S1P in an in vitro assay, and virtually all neurons responded with a rapid retraction of neurites and growth cone collapse which were associated with RhoA and ROCK activation. The S1P1 receptor agonist SEW2871 neither activated RhoA or neurite retraction, nor was S1P-induced neurite retraction mitigated in S1P1-deficient neurons. Depletion of S1P3 receptors however resulted in a dramatic inhibition of S1P-induced neurite retraction and was on the contrary associated with a significant elongation of neuronal processes in response to S1P. Opposing responses to S1P could be observed in the same neuron population, where S1P could activate S1P1 receptors to stimulate elongation or S1P3 receptors and retraction. S1P was, for the first time in sensory neurons, linked to the phosphorylation of collapsin response-mediated protein-2 (CRMP2), which was inhibited by ROCK inhibition. The improved sensory recovery after crush injury further supported the relevance of a critical role for S1P and receptors in fine-tuning axonal outgrowth in peripheral neurons. PMID:29066950

Early prevention of obesity

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Claudio Maffeis

2014-06-01

Full Text Available Childhood obesity is the metabolic disorder with the highest prevalence in both children and adults. Urgency to treat and prevent childhood obesity is based on the clear evidence that obesity tends to track from childhood to adulthood, is associated to morbidity also in childhood and to long-term mortality. Early life, i.e., intrauterine life and the first two years, is a sensitive window for prevention. Anatomical and functional maturation of the hypothalamic structures devoted to regulating energy intake and expenditure and body size mainly occurs in the first 1,000 days of life. Therefore, factors affecting the foetal exposition to maternal metabolic environment and early postnatal nutrition are crucial in modulating the definition of the metabolic programming processes in the brain. Maternal diseases, mainly malnutrition for defect or excess, obesity and diabetes, placental disorders and dysfunctions, maternal use of alcohol and drugs, smoking, affect long term metabolic programming of the foetus with lifelong consequences. Similarly, early nutrition contributes to complete the long-term metabolic regulating framework initiated in the uterus. Breastfeeding, adequate weaning, attention to portion size and diet composition are potential tools for reducing the obesity risk later in childhood. Longitudinal randomized controlled studies are needed for exploring the efficacy of obesity prevention strategies initiated after conception.Proceedings of the 10th International Workshop on Neonatology · Cagliari (Italy · October 22nd-25th, 2014 · The last ten years, the next ten years in Neonatology Guest Editors: Vassilios Fanos, Michele Mussap, Gavino Faa, Apostolos Papageorgiou

The early noncoding region of human papillomavirus type 16 is regulated by cytoplasmic polyadenylation factors

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Glahder, Jacob-Andreas Harald; Kristiansen, Karen; Durand, Marjorie

2010-01-01

All human papillomavirus type 16 (HPV-16) early mRNAs are polyadenylated at the poly(A) signal within the early 3' untranslated region (3'UTR). The 3'end of the early E5 open reading frame and the 3'UTR of HPV-16 is very AU-rich, with five regions similar to cytoplasmic polyadenylation elements (...

Children's Early Approaches to Learning and Academic Trajectories through Fifth Grade

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Li-Grining, Christine P.; Votruba-Drzal, Elizabeth; Maldonado-Carreno, Carolina; Haas, Kelly

2010-01-01

Children's early approaches to learning (ATL) enhance their adaptation to the demands they experience with the start of formal schooling. The current study uses individual growth modeling to investigate whether children's early ATL, which includes persistence, emotion regulation, and attentiveness, explain individual differences in their academic…

Casein kinase 1 alpha regulates chromosome congression and separation during mouse oocyte meiotic maturation and early embryo development.

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Lu Wang

Full Text Available Casein kinase I alpha (CK1α is a member of serine/threonine protein kinase, generally present in all eukaryotes. In mammals, CK1α regulates the transition from interphase to metaphase in mitosis. However, little is known about its role in meiosis. Here we examined Ck1α mRNA and protein expression, as well as its subcellular localization in mouse oocytes from germinal vesicle to the late 1-cell stage. Our results showed that the expression level of CK1α was increased in metaphase. Immunostaining results showed that CK1α colocalized with condensed chromosomes during oocyte meiotic maturation and early embryo development. We used the loss-of-function approach by employing CK1α specific morpholino injection to block the function of CK1α. This functional blocking leads to failure of polar body 1 (PB1 extrusion, chromosome misalignment and MII plate incrassation. We further found that D4476, a specific and efficient CK1 inhibitor, decreased the rate of PB1 extrusion. Moreover, D4476 resulted in giant polar body extrusion, oocyte pro-MI arrest, chromosome congression failure and impairment of embryo developmental potential. In addition, we employed pyrvinium pamoate (PP, an allosteric activator of CK1α, to enhance CK1α activity in oocytes. Supplementation of PP induced oocyte meiotic maturation failure, severe congression abnormalities and misalignment of chromosomes. Taken together, our study for the first time demonstrates that CK1α is required for chromosome alignment and segregation during oocyte meiotic maturation and early embryo development.

Short-term mastication after weaning upregulates GABAergic signalling and reduces dendritic spine in thalamus.

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Ogawa, Mana; Nagai, Toshitada; Saito, Yoshikazu; Miyaguchi, Hitonari; Kumakura, Kei; Abe, Keiko; Asakura, Tomiko

2018-04-06

Mastication enhances brain function and mental health, but little is known about the molecular mechanisms underlying the effects of mastication on neural development in early childhood. Therefore, we analysed the gene expression in juvenile neural circuits in rats fed with a soft or chow diet immediately after weaning. We observed that the gene expression patterns in the thalamus varied depending on the diet. Furthermore, gene ontology analysis revealed that two terms were significantly enhanced: chemical synaptic transmission and positive regulation of dendritic spine morphogenesis. With respect to chemical synaptic transmission, glutamate decarboxylase and GABA receptors were upregulated in the chow diet group. The related genes, including vesicular GABA transporter, were also upregulated, suggesting that mastication activates GABAergic signalling. With respect to dendritic spine morphogenesis, Ingenuity Pathway Analysis predicted fewer extension of neurites and neurons and fewer number of branches in the chow diet group. The numbers of spines in the ventral posterolateral and posteromedial regions were significantly decreased. These results suggest that mastication in the early developing period upregulates GABAergic signalling genes, with a decrease of spines in the thalamus. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Minsky and dynamic macroprudential regulation

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Jan Kregel

2014-06-01

Full Text Available In the context of current debates about the proper form of prudential regulation and proposals for the imposition of liquidity and capital ratios, the paper examines Hyman Minsky’s work as a consultant to government agencies exploring financial regulatory reform in the 1960s. As the author explains, this often-overlooked early work, a precursor to Minsky’s “financial instability hypothesis”, serves as yet another useful guide to explaining why regulation and supervision in the lead-up to the 2008 financial crisis were flawed, and why the approach to reregulation after the crisis has been incomplete.

Child Self-Regulation, Parental Secure Base Scripts, and At-Risk Kindergartners' Academic Achievement

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McLear, Caitlin; Trentacosta, Christopher J.; Smith-Darden, Joanne

2016-01-01

Research Findings: Early reading and mathematics skills predict later academic success, and child self-regulation and secure parent-child relationships are both predictors of early academic skills. Self-regulatory and family relationship factors have rarely been studied together as predictors of early academic success in populations of young…

The role of neprilysin in regulating the hair cycle.

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Naoko Morisaki

Full Text Available In most mammals, each hair follicle undergoes a cyclic process of growing, regressing and resting phases (anagen, catagen, telogen, respectively called the hair cycle. Various biological factors have been reported to regulate or to synchronize with the hair cycle. Some factors involved in the extracellular matrix, which is a major component of skin tissue, are also thought to regulate the hair cycle. We have focused on an enzyme that degrades elastin, which is associated with skin elasticity. Since our previous study identified skin fibroblast elastase as neprilysin (NEP, we examined the fluctuation of NEP enzyme activity and its expression during the synchronized hair cycle of rats. NEP activity in the skin was elevated at early anagen, and decreased during catagen to telogen. The expression of NEP mRNA and protein levels was modulated similarly. Immunostaining showed changes in NEP localization throughout the hair cycle, from the follicular epithelium during early anagen to the dermal papilla during catagen. To determine whether NEP plays an important role in regulating the hair cycle, we used a specific inhibitor of NEP (NPLT. NPLT was applied topically daily to the dorsal skin of C3H mice, which had been depilated in advance. Mice treated with NPLT had significantly suppressed hair growth. These data suggest that NEP plays an important role in regulating the hair cycle by its increased expression and activity in the follicular epithelium during early anagen.

The Proteomic Signature of Aspergillus fumigatus During Early Development*

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Cagas, Steven E.; Jain, Mohit Raja; Li, Hong; Perlin, David S.

2011-01-01

Aspergillus fumigatus is a saprophytic fungus that causes a range of diseases in humans including invasive aspergillosis. All forms of disease begin with the inhalation of conidia, which germinate and develop. Four stages of early development were evaluated using the gel free system of isobaric tagging for relative and absolute quantitation to determine the full proteomic profile of the pathogen. A total of 461 proteins were identified at 0, 4, 8, and 16 h and fold changes for each were established. Ten proteins including the hydrophobin rodlet protein RodA and a protein involved in melanin synthesis Abr2 were found to decrease relative to conidia. To generate a more comprehensive view of early development, a whole genome microarray analysis was performed comparing conidia to 8 and 16 h of growth. A total of 1871 genes were found to change significantly at 8 h with 1001 genes up-regulated and 870 down-regulated. At 16 h, 1235 genes changed significantly with 855 up-regulated and 380 down-regulated. When a comparison between the proteomics and microarray data was performed at 8 h, a total of 22 proteins with significant changes also had corresponding genes that changed significantly. When the same comparison was performed at 16 h, 12 protein and gene combinations were found. This study, the most comprehensive to date, provides insights into early pathways activated during growth and development of A. fumigatus. It reveals a pathogen that is gearing up for rapid growth by building translation machinery, generating ATP, and is very much committed to aerobic metabolism. PMID:21825280

Pluripotent Stem Cell Studies Elucidate the Underlying Mechanisms of Early Embryonic Development

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Lingyu Li

2011-03-01

Full Text Available Early embryonic development is a multi-step process that is intensively regulated by various signaling pathways. Because of the complexity of the embryo and the interactions between the germ layers, it is very difficult to fully understand how these signals regulate embryo patterning. Recently, pluripotent stem cell lines derived from different developmental stages have provided an in vitro system for investigating molecular mechanisms regulating cell fate decisions. In this review, we summarize the major functions of the BMP, FGF, Nodal and Wnt signaling pathways, which have well-established roles in vertebrate embryogenesis. Then, we highlight recent studies in pluripotent stem cells that have revealed the stage-specific roles of BMP，FGF and Nodal pathways during neural differentiation. These findings enhance our understanding of the stepwise regulation of embryo patterning by particular signaling pathways and provide new insight into the mechanisms underlying early embryonic development.

Pure neuritic leprosy: Resolving diagnostic issues in acid fast bacilli (AFB)-negative nerve biopsies: A single centre experience from South India.

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Hui, Monalisa; Uppin, Megha S; Challa, Sundaram; Meena, A K; Kaul, Subhash

2015-01-01

Demonstration of lepra bacilli is essential for definite or unequivocal diagnosis of pure neuritic leprosy (PNL) on nerve biopsy. However, nerves always do not show bacilli owing to the changes of previous therapy or due to low bacillary load in tuberculoid forms. In absence of granuloma or lepra bacilli, other morphologic changes in endoneurium and perineurium can be of help in making a probable diagnosis of PNL and treating the patient with multidrug therapy. Forty-six biopsies of PNL were retrospectively reviewed and histologic findings were compared with 25 biopsies of non leprosy neuropathies (NLN) including vasculitic neuropathy and chronic inflammatory demyelinating polyneuropathy (CIDP). The distribution of endoneurial infiltrate and fibrosis, perineurial thickening, and myelin abnormalities were compared between PNL and NLN biopsies and analyzed by Chi-square test. Out of 46 PNL casses, 24 (52.17 %) biopsies were negative for acid fast bacilli (AFB). In these cases, the features which favor a diagnosis of AFB-negative PNL were endoneurial infiltrate (51.1%), endoneurial fibrosis (54.2%), perineurial thickening (70.8%), and reduced number of myelinated nerve fibers (75%). Nerve biopsy is an efficient tool to diagnose PNL and differentiate it from other causes of NLN. In absence of AFB, the diagnosis of PNL is challenging. In this article, we have satisfactorily evaluated the various hisopthological features and found that endoneurial inflammation, dense fibrosis, and reduction in the number of myelinated nerve fibers are strong supportive indicators of PNL regardless of AFB positivity.

Responsive feeding: establishing healthy eating behaviour early on ...

African Journals Online (AJOL)

2013-04-12

Apr 12, 2013 ... facilitation of self-regulation skills early in life may predict future food intake ... eating behaviour through communicating their attitudes and beliefs about ..... as well as disturbances in self-esteem, body image and socialisation ...

Transcriptomic analysis highlights epigenetic and transcriptional regulation during zygotic embryo development of Pinus pinaster.

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de Vega-Bartol, José J; Simões, Marta; Lorenz, W Walter; Rodrigues, Andreia S; Alba, Rob; Dean, Jeffrey F D; Miguel, Célia M

2013-08-30

It is during embryogenesis that the plant body plan is established and the meristems responsible for all post-embryonic growth are specified. The molecular mechanisms governing conifer embryogenesis are still largely unknown. Their elucidation may contribute valuable information to clarify if the distinct features of embryo development in angiosperms and gymnosperms result from differential gene regulation. To address this issue, we have performed the first transcriptomic analysis of zygotic embryo development in a conifer species (Pinus pinaster) focusing our study in particular on regulatory genes playing important roles during plant embryo development, namely epigenetic regulators and transcription factors. Microarray analysis of P. pinaster zygotic embryogenesis was performed at five periods of embryo development from early developing to mature embryos. Our results show that most changes in transcript levels occurred in the first and the last embryo stage-to-stage transitions, namely early to pre-cotyledonary embryo and cotyledonary to mature embryo. An analysis of functional categories for genes that were differentially expressed through embryogenesis highlighted several epigenetic regulation mechanisms. While putative orthologs of transcripts associated with mechanisms that target transposable elements and repetitive sequences were strongly expressed in early embryogenesis, PRC2-mediated repression of genes seemed more relevant during late embryogenesis. On the other hand, functions related to sRNA pathways appeared differentially regulated across all stages of embryo development with a prevalence of miRNA functions in mid to late embryogenesis. Identification of putative transcription factor genes differentially regulated between consecutive embryo stages was strongly suggestive of the relevance of auxin responses and regulation of auxin carriers during early embryogenesis. Such responses could be involved in establishing embryo patterning. Later in

In vivo characterization of cortical and white matter neuroaxonal pathology in early multiple sclerosis.

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Granberg, Tobias; Fan, Qiuyun; Treaba, Constantina Andrada; Ouellette, Russell; Herranz, Elena; Mangeat, Gabriel; Louapre, Céline; Cohen-Adad, Julien; Klawiter, Eric C; Sloane, Jacob A; Mainero, Caterina

2017-11-01

Neuroaxonal pathology is a main determinant of disease progression in multiple sclerosis; however, its underlying pathophysiological mechanisms, including its link to inflammatory demyelination and temporal occurrence in the disease course are still unknown. We used ultra-high field (7 T), ultra-high gradient strength diffusion and T1/T2-weighted myelin-sensitive magnetic resonance imaging to characterize microstructural changes in myelin and neuroaxonal integrity in the cortex and white matter in early stage multiple sclerosis, their distribution in lesional and normal-appearing tissue, and their correlations with neurological disability. Twenty-six early stage multiple sclerosis subjects (disease duration ≤5 years) and 24 age-matched healthy controls underwent 7 T T2*-weighted imaging for cortical lesion segmentation and 3 T T1/T2-weighted myelin-sensitive imaging and neurite orientation dispersion and density imaging for assessing microstructural myelin, axonal and dendrite integrity in lesional and normal-appearing tissue of the cortex and the white matter. Conventional mean diffusivity and fractional anisotropy metrics were also assessed for comparison. Cortical lesions were identified in 92% of early multiple sclerosis subjects and they were characterized by lower intracellular volume fraction (P = 0.015 by paired t-test), lower myelin-sensitive contrast (P = 0.030 by related-samples Wilcoxon signed-rank test) and higher mean diffusivity (P = 0.022 by related-samples Wilcoxon signed-rank test) relative to the contralateral normal-appearing cortex. Similar findings were observed in white matter lesions relative to normal-appearing white matter (all P test) and lower fractional anisotropy (P Wilcoxon signed-rank test) suggestive of less coherent underlying fibre orientation. Additionally, the normal-appearing white matter in multiple sclerosis subjects had diffusely lower intracellular volume fractions than the white matter in controls (P = 0.029 by unpaired

The USA prepares to change its radiation protection regulations

International Nuclear Information System (INIS)

Anon.

1990-01-01

The US Nuclear Regulatory Commission (NRC) is preparing to revise its basic regulation on protection of people from ionizing radiation. The current regulation, ''Standards for protection against radiation'' -commonly referred to as ''Part 20'' - was originally published for comment in 1955. The regulation was based on early recommendations from the International Commission on Radiological Protection (ICRP). In 1977, the ICRP made major changes in its recommendations, known as ICRP-26. In 1990, the NRC Commissioners approved a new Part 20 reflecting ICRP-26, but improvements are to be specified and considered before a new regulation is published. (author)

Changes in miRNA Expression Profiling during Neuronal Differentiation and Methyl Mercury-Induced Toxicity in Human in Vitro Models

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Giorgia Pallocca

2014-08-01

Full Text Available MicroRNAs (miRNAs are implicated in the epigenetic regulation of several brain developmental processes, such as neurogenesis, neuronal differentiation, neurite outgrowth, and synaptic plasticity. The main aim of this study was to evaluate whether miRNA expression profiling could be a useful approach to detect in vitro developmental neurotoxicity. For this purpose, we assessed the changes in miRNA expression caused by methyl mercury chloride (MeHgCl, a well-known developmental neurotoxicant, comparing carcinoma pluripotent stem cells (NT-2 with human embryonic stem cells (H9, both analyzed during the early stage of neural progenitor commitment into neuronal lineage. The data indicate the activation of two distinct miRNA signatures, one activated upon neuronal differentiation and another upon MeHgCl-induced toxicity. Particularly, exposure to MeHgCl elicited, in both neural models, the down-regulation of the same six out of the ten most up-regulated neuronal pathways, as shown by the up-regulation of the corresponding miRNAs and further assessment of gene ontology (GO term and pathway enrichment analysis. Importantly, some of these common miRNA-targeted pathways defined in both cell lines are known to play a role in critical developmental processes, specific for neuronal differentiation, such as axon guidance and neurotrophin-regulated signaling. The obtained results indicate that miRNAs expression profiling could be a promising tool to assess developmental neurotoxicity pathway perturbation, contributing towards improved predictive human toxicity testing.

Developmental neurotoxicity of different pesticides in PC-12 cells in vitro

Energy Technology Data Exchange (ETDEWEB)

Christen, Verena [University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH-4132, Muttenz (Switzerland); Rusconi, Manuel; Crettaz, Pierre [Federal Office of Public Health, Division Chemical Products, 3003 Bern (Switzerland); Fent, Karl, E-mail: karl.fent@bluewin.ch [University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH-4132, Muttenz (Switzerland); Swiss Federal Institute of Technology Zürich (ETH Zürich), Department of Environmental Systems Sciences, Institute of Biogeochemistry and Pollution Dynamics, CH-8092 Zürich (Switzerland)

2017-06-15

The detection of developmental neurotoxicity (DNT) of chemicals has high relevance for protection of human health. However, DNT of many pesticides is only little known. Furthermore, validated in vitro systems for assessment of DNT are not well established. Here we employed the rat phaeochromocytoma cell line PC-12 to evaluate DNT of 18 frequently used pesticides of different classes, including neonicotinoids, pyrethroids, organophosphates, organochlorines, as well as quaternary ammonium compounds, the organic compound used in pesticides, piperonyl butoxide, as well as the insect repellent diethyltoluamide (DEET). We determined the outgrowth of neurites in PC-12 cells co-treated with nerve growth factor and different concentrations of biocides for 5 days. Furthermore, we determined transcriptional alterations of selected genes that may be associated with DNT, such as camk2α and camk2β, gap-43, neurofilament-h, tubulin-α and tubulin-β. Strong and dose- dependent inhibition of neurite outgrowth was induced by azamethiphos and chlorpyrifos, and dieldrin and heptachlor, which was correlated with up-regulation of gap-43. No or only weak effects on neurite outgrowth and transcriptional alterations occurred for neonicotinoids acetamiprid, clothianidin, imidacloprid and thiamethoxam, the pyrethroids λ-cyhalothrin, cyfluthrin, deltamethrin, and permethrin, the biocidal disinfectants C12-C14-alkyl(ethylbenzyl)dimethylammonium (BAC), benzalkonium chloride and barquat (dimethyl benzyl ammonium chloride), and piperonyl butoxide and DEET. Our study confirms potential developmental neurotoxicity of some pesticides and provides first evidence that azamethiphos has the potential to act as a developmental neurotoxic compound. We also demonstrate that inhibition of neurite outgrowth and transcriptional alterations of gap-43 expression correlate, which suggests the employment of gap-43 expression as a biomarker for detection and initial evaluation of potential DNT of chemicals

Developmental neurotoxicity of different pesticides in PC-12 cells in vitro

International Nuclear Information System (INIS)

Christen, Verena; Rusconi, Manuel; Crettaz, Pierre; Fent, Karl

2017-01-01

The detection of developmental neurotoxicity (DNT) of chemicals has high relevance for protection of human health. However, DNT of many pesticides is only little known. Furthermore, validated in vitro systems for assessment of DNT are not well established. Here we employed the rat phaeochromocytoma cell line PC-12 to evaluate DNT of 18 frequently used pesticides of different classes, including neonicotinoids, pyrethroids, organophosphates, organochlorines, as well as quaternary ammonium compounds, the organic compound used in pesticides, piperonyl butoxide, as well as the insect repellent diethyltoluamide (DEET). We determined the outgrowth of neurites in PC-12 cells co-treated with nerve growth factor and different concentrations of biocides for 5 days. Furthermore, we determined transcriptional alterations of selected genes that may be associated with DNT, such as camk2α and camk2β, gap-43, neurofilament-h, tubulin-α and tubulin-β. Strong and dose- dependent inhibition of neurite outgrowth was induced by azamethiphos and chlorpyrifos, and dieldrin and heptachlor, which was correlated with up-regulation of gap-43. No or only weak effects on neurite outgrowth and transcriptional alterations occurred for neonicotinoids acetamiprid, clothianidin, imidacloprid and thiamethoxam, the pyrethroids λ-cyhalothrin, cyfluthrin, deltamethrin, and permethrin, the biocidal disinfectants C12-C14-alkyl(ethylbenzyl)dimethylammonium (BAC), benzalkonium chloride and barquat (dimethyl benzyl ammonium chloride), and piperonyl butoxide and DEET. Our study confirms potential developmental neurotoxicity of some pesticides and provides first evidence that azamethiphos has the potential to act as a developmental neurotoxic compound. We also demonstrate that inhibition of neurite outgrowth and transcriptional alterations of gap-43 expression correlate, which suggests the employment of gap-43 expression as a biomarker for detection and initial evaluation of potential DNT of chemicals

NeuronMetrics: software for semi-automated processing of cultured neuron images.

Science.gov (United States)

Narro, Martha L; Yang, Fan; Kraft, Robert; Wenk, Carola; Efrat, Alon; Restifo, Linda L

2007-03-23

Using primary cell culture to screen for changes in neuronal morphology requires specialized analysis software. We developed NeuronMetrics for semi-automated, quantitative analysis of two-dimensional (2D) images of fluorescently labeled cultured neurons. It skeletonizes the neuron image using two complementary image-processing techniques, capturing fine terminal neurites with high fidelity. An algorithm was devised to span wide gaps in the skeleton. NeuronMetrics uses a novel strategy based on geometric features called faces to extract a branch number estimate from complex arbors with numerous neurite-to-neurite contacts, without creating a precise, contact-free representation of the neurite arbor. It estimates total neurite length, branch number, primary neurite number, territory (the area of the convex polygon bounding the skeleton and cell body), and Polarity Index (a measure of neuronal polarity). These parameters provide fundamental information about the size and shape of neurite arbors, which are critical factors for neuronal function. NeuronMetrics streamlines optional manual tasks such as removing noise, isolating the largest primary neurite, and correcting length for self-fasciculating neurites. Numeric data are output in a single text file, readily imported into other applications for further analysis. Written as modules for ImageJ, NeuronMetrics provides practical analysis tools that are easy to use and support batch processing. Depending on the need for manual intervention, processing time for a batch of approximately 60 2D images is 1.0-2.5 h, from a folder of images to a table of numeric data. NeuronMetrics' output accelerates the quantitative detection of mutations and chemical compounds that alter neurite morphology in vitro, and will contribute to the use of cultured neurons for drug discovery.

Family Income Dynamics, Early Childhood Education and Care, and Early Child Behavior Problems in Norway

Science.gov (United States)

Zachrisson, Henrik Daae; Dearing, Eric

2014-01-01

The sociopolitical context of Norway includes low poverty rates and universal access to subsidized and regulated Early Childhood Education and Care (ECEC). In this context, the association between family income dynamics and changes in early child behavior problems was investigated, as well as whether high quality ECEC buffers children from the effects of income dynamics. In a population-based sample (N = 75,296), within-family changes in income-to-needs predicted changes in externalizing and internalizing problems (from age 18 to 36 months), particularly for lower-income children. For internalizing problems, ECEC buffered the effect of income-to-needs changes. These findings lend further support to the potential benefits of ECEC for children from lower-income families. PMID:25345342

Early prevention of obesity

OpenAIRE

Claudio Maffeis

2014-01-01

Childhood obesity is the metabolic disorder with the highest prevalence in both children and adults. Urgency to treat and prevent childhood obesity is based on the clear evidence that obesity tends to track from childhood to adulthood, is associated to morbidity also in childhood and to long-term mortality. Early life, i.e., intrauterine life and the first two years, is a sensitive window for prevention. Anatomical and functional maturation of the hypothalamic structures devoted to regulating...

Tenascin-C in peripheral nerve morphogenesis.

Science.gov (United States)

Chiquet, M; Wehrle-Haller, B

1994-01-01

The extracellular matrix (ECM) molecule tenascin/cytotactin (TN-C) is expressed at a high level by satellite (glial precursor) cells in developing peripheral nerves of the chick embryo; synthesis of its mRNA peaks at the time period when axonal growth is maximal. When offered as a substrate in vitro, TN-C mediates neurite outgrowth by both motor and sensory neurons. The ability to grow neurites on TN-C is developmentally regulated: sensory neurons from 4-day chick embryos (the stage at which peripheral nerves start to develop) grow immediately and rapidly, whereas neurons from older embryos respond with a long delay. A TN-C domain responsible for this activity is located within the C-terminal (distal) portion of TN-C subunits. Integrin receptors seem to be involved on peripheral neurites because their growth on TN-C is completely blocked by antibodies to beta 1 integrins. In striking contrast to neuronal processes, nerve satellite cells can attach to a TN-C substrate but are completely inhibited in their migratory activity. Artificial substrate borders between tenascin and fibronectin or laminin act as selective barriers that allow neurites to pass while holding up satellite cells. The repulsive action of TN-C on satellite cells is similar to that observed for other cell types and is likely to be mediated by additional TN-C domains. In view of these data, it is surprising that mice seem to develop normally without a functional TN-C gene. TN-C is likely to be redundant, that is, its dual action on cell adhesion is shared by other molecules.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of Regenerative Phenotype of Unrestricted Somatic Stem Cells (USSC) from Human Umbilical Cord Blood (hUCB) by Functional Secretome Analysis*

Science.gov (United States)

Schira, Jessica; Falkenberg, Heiner; Hendricks, Marion; Waldera-Lupa, Daniel M.; Kögler, Gesine; Meyer, Helmut E.; Müller, Hans Werner; Stühler, Kai

2015-01-01

Stem cell transplantation is a promising therapeutic strategy to enhance axonal regeneration after spinal cord injury. Unrestricted somatic stem cells (USSC) isolated from human umbilical cord blood is an attractive stem cell population available at GMP grade without any ethical concerns. It has been shown that USSC transplantation into acute injured rat spinal cords leads to axonal regrowth and significant locomotor recovery, yet lacking cell replacement. Instead, USSC secrete trophic factors enhancing neurite growth of primary cortical neurons in vitro. Here, we applied a functional secretome approach characterizing proteins secreted by USSC for the first time and validated candidate neurite growth promoting factors using primary cortical neurons in vitro. By mass spectrometric analysis and exhaustive bioinformatic interrogation we identified 1156 proteins representing the secretome of USSC. Using Gene Ontology we revealed that USSC secretome contains proteins involved in a number of relevant biological processes of nerve regeneration such as cell adhesion, cell motion, blood vessel formation, cytoskeleton organization and extracellular matrix organization. We found for instance that 31 well-known neurite growth promoting factors like, e.g. neuronal growth regulator 1, NDNF, SPARC, and PEDF span the whole abundance range of USSC secretome. By the means of primary cortical neurons in vitro assays we verified SPARC and PEDF as significantly involved in USSC mediated neurite growth and therewith underline their role in improved locomotor recovery after transplantation. From our data we are convinced that USSC are a valuable tool in regenerative medicine as USSC's secretome contains a comprehensive network of trophic factors supporting nerve regeneration not only by a single process but also maintained its regenerative phenotype by a multitude of relevant biological processes. PMID:26183719

Green tea polyphenols alleviate early BBB damage during experimental focal cerebral ischemia through regulating tight junctions and PKCalpha signaling.

Science.gov (United States)

Liu, Xiaobai; Wang, Zhenhua; Wang, Ping; Yu, Bo; Liu, Yunhui; Xue, Yixue

2013-07-21

It has been supposed that green tea polyphenols (GTPs) have neuroprotective effects on brain damage after brain ischemia in animal experiments. Little is known regarding GTPs' protective effects against the blood-brain barrier (BBB) disruption after ischemic stroke. We investigated the effects of GTPs on the expression of claudin-5, occludin, and ZO-1, and the corresponding cellular mechanisms involved in the early stage of cerebral ischemia. Male Wistar rats were subjected to a middle cerebral artery occlusion (MCAO) for 0, 30, 60, and 120 min. GTPs (400 mg/kg/day) or vehicle was administered by intragastric gavage twice a day for 30 days prior to MCAO. At different time points, the expression of claudin-5, occludin, ZO-1, and PKCα signaling pathway in microvessel fragments of cerebral ischemic tissue were evaluated. GTPs reduced BBB permeability at 60 min and 120 min after ischemia as compared with the vehicle group. Transmission electron microscopy also revealed that GTPs could reverse the opening of tight junction (TJ) barrier at 60 min and 120 min after MACO. The decreased mRNA and protein expression levels of claudin-5, occludin, and ZO-1 in microvessel fragments of cerebral ischemic tissue were significantly prevented by treatment with GTPs at the same time points after ischemia in rats. Furthermore, GTPs could attenuate the increase in the expression levels of PKCα mRNA and protein caused by cerebral ischemia. These results demonstrate that GTPs may act as a potential neuroprotective agent against BBB damage at the early stage of focal cerebral ischemia through the regulation of TJ and PKCα signaling.

The Brakeless co-regulator can directly activate and repress transcription in early Drosophila embryos.

Science.gov (United States)

Crona, Filip; Holmqvist, Per-Henrik; Tang, Min; Singla, Bhumica; Vakifahmetoglu-Norberg, Helin; Fantur, Katrin; Mannervik, Mattias

2015-11-01

The Brakeless protein performs many important functions during Drosophila development, but how it controls gene expression is poorly understood. We previously showed that Brakeless can function as a transcriptional co-repressor. In this work, we perform transcriptional profiling of brakeless mutant embryos. Unexpectedly, the majority of affected genes are down-regulated in brakeless mutants. We demonstrate that genomic regions in close proximity to some of these genes are occupied by Brakeless, that over-expression of Brakeless causes a reciprocal effect on expression of these genes, and that Brakeless remains an activator of the genes upon fusion to an activation domain. Together, our results show that Brakeless can both repress and activate gene expression. A yeast two-hybrid screen identified the Mediator complex subunit Med19 as interacting with an evolutionarily conserved part of Brakeless. Both down- and up-regulated Brakeless target genes are also affected in Med19-depleted embryos, but only down-regulated targets are influenced in embryos depleted of both Brakeless and Med19. Our data provide support for a Brakeless activator function that regulates transcription by interacting with Med19. We conclude that the transcriptional co-regulator Brakeless can either activate or repress transcription depending on context. Copyright © 2015 Elsevier Inc. All rights reserved.

The Role of Behavioral Self-Regulation in Learning to Read: A 2-Year Longitudinal Study of Icelandic Preschool Children

Science.gov (United States)

Birgisdóttir, Freyja; Gestsdóttir, Steinunn; Thorsdóttir, Fanney

2015-01-01

Research Findings: Research suggests that behavioral self-regulation skills are critical for early school success, including success in literacy, but few studies have explored the relations that behavioral self-regulation may have with different components of early literacy development. The present study investigated the longitudinal contribution…

Preschool self regulation predicts later mental health and educational achievement in very preterm and typically developing children.

Science.gov (United States)

Woodward, Lianne J; Lu, Zhigang; Morris, Alyssa R; Healey, Dione M

2017-02-01

To examine the extent to which preschool emotional and behavioral regulatory difficulties were associated with an increased risk of later mental health and educational problems. Of particular interest was whether early regulatory abilities contributed to later risk once baseline child behavioral adjustment and cognitive function were taken into account. Data were drawn from a prospective longitudinal study of 223 children born very preterm (VPT; Regulation Checklist, and (3) tester ratings of child behavior during neuropsychological testing. At age 9 years, mental health and educational achievement were assessed using the Development and Well-being Assessment interview and the Woodcock Johnson-III Tests of Achievement. VPT-born children had poorer emotional and behavioral regulation across all measures and time points. They also had higher rates of DSM-IV mental health disorder and educational delay at age 9. Across both study groups, poorer self regulation was associated with an increased risk of ADHD, conduct disorder, anxiety disorders and any disorder net of preschool child behavior problems and social risk. In contrast, only associations between early regulation and later language and any educational delay remained significant after adjustment for preschool cognitive functioning and family social risk. Early assessment of regulation in addition to behavioral screening may improve the early identification of preschool children at mental health risk.

Early Life Experience and Gut Microbiome: The Brain-Gut-Microbiota Signaling System.

Science.gov (United States)

Cong, Xiaomei; Henderson, Wendy A; Graf, Joerg; McGrath, Jacqueline M

2015-10-01

Over the past decades, advances in neonatal care have led to substantial increases in survival among preterm infants. With these gains, recent concerns have focused on increases in neurodevelopment morbidity related to the interplay between stressful early life experiences and the immature neuroimmune systems. This interplay between these complex mechanisms is often described as the brain-gut signaling system. The role of the gut microbiome and the brain-gut signaling system have been found to be remarkably related to both short- and long-term stress and health. Recent evidence supports that microbial species, ligands, and/or products within the developing intestine play a key role in early programming of the central nervous system and regulation of the intestinal innate immunity. The purpose of this state-of-the-science review is to explore the supporting evidence demonstrating the importance of the brain-gut-microbiota axis in regulation of early life experience. We also discuss the role of gut microbiome in modulating stress and pain responses in high-risk infants. A conceptual framework has been developed to illustrate the regulation mechanisms involved in early life experience. The science in this area is just beginning to be uncovered; having a fundamental understanding of these relationships will be important as new discoveries continue to change our thinking, leading potentially to changes in practice and targeted interventions.

Assessing self-regulated learning in early childhood education: Difficulties, needs, and prospects.

Science.gov (United States)

de la Fuente Arias, Jesús; Lozano Díaz, Antonia

2010-05-01

Self-regulated learning is one of the main processes being investigated today within developmental and educational psychology; however, the research has come up against a number of challenges for which no satisfactory response has been found, and which are impeding progress in the field. These challenges are two-fold: one part is methodological, as the process of self-regulation must be evaluated at the very moment in which it occurs, and the other part is developmental, as these processes have not been fully assessed in children under the age of 6 years. This article gives a broad overview of these challenges, as well as prospects for future solutions which are beginning to take shape.

Prion protein cleavage fragments regulate adult neural stem cell quiescence through redox modulation of mitochondrial fission and SOD2 expression.

Science.gov (United States)

Collins, Steven J; Tumpach, Carolin; Groveman, Bradley R; Drew, Simon C; Haigh, Cathryn L

2018-03-24

Neurogenesis continues in the post-developmental brain throughout life. The ability to stimulate the production of new neurones requires both quiescent and actively proliferating pools of neural stem cells (NSCs). Actively proliferating NSCs ensure that neurogenic demand can be met, whilst the quiescent pool makes certain NSC reserves do not become depleted. The processes preserving the NSC quiescent pool are only just beginning to be defined. Herein, we identify a switch between NSC proliferation and quiescence through changing intracellular redox signalling. We show that N-terminal post-translational cleavage products of the prion protein (PrP) induce a quiescent state, halting NSC cellular growth, migration, and neurite outgrowth. Quiescence is initiated by the PrP cleavage products through reducing intracellular levels of reactive oxygen species. First, inhibition of redox signalling results in increased mitochondrial fission, which rapidly signals quiescence. Thereafter, quiescence is maintained through downstream increases in the expression and activity of superoxide dismutase-2 that reduces mitochondrial superoxide. We further observe that PrP is predominantly cleaved in quiescent NSCs indicating a homeostatic role for this cascade. Our findings provide new insight into the regulation of NSC quiescence, which potentially could influence brain health throughout adult life.

Self-recognition: a constraint on the formation of electrical coupling in neurons.

Science.gov (United States)

Guthrie, P B; Lee, R E; Rehder, V; Schmidt, M F; Kater, S B

1994-03-01

Electrical coupling between specific neurons is important for proper function of many neuronal circuits. Identified cultured neurons from the snail Helisoma show a strong correlation between electrical coupling and presence of gap junction plaques in freeze-fracture replicas. Gap junction plaques, however, were never seen between overlapping neurites from a single neuron, even though those same neurites formed gap junctions with neurites from another essentially identical identified neuron. This observation suggests that a form of self-recognition inhibits reflexive gap junction formation between sibling neurites. When one or both of those growth cones had been physically isolated from the neuronal cell body, both electrical coupling and gap junction plaques, between growth cones from the same neuron, were observed to form rapidly (within 30 min). Thus, inhibition of electrical coupling between sibling neurites apparently depends on cytoplasmic continuity between neurites, and not the molecular composition of neurite membrane. The formation of gap junctions is not likely due to the isolation process; rather, the physical isolation appears to release an inhibition of reflexive gap junction formation. These data demonstrate the existence of a previously unknown constraint on the formation of electrical synapses.

Moving Ahead in the Study of the Development of Emotion Regulation

Science.gov (United States)

Cole, Pamela M.

2014-01-01

This special section on the development of emotion regulation highlights several important new directions for research. Specifically, the findings of these studies indicate that: (1) emotion regulation develops across the lifespan and not just in early childhood and does so in complex ways, (2) it is necessary to distinguish among emotions to…

Negative feedback regulation of Homer 1a on norepinephrine-dependent cardiac hypertrophy

Energy Technology Data Exchange (ETDEWEB)

Chiarello, Carmelina; Bortoloso, Elena; Carpi, Andrea; Furlan, Sandra; Volpe, Pompeo, E-mail: pompeo.volpe@unipd.it

2013-07-15

Homers are scaffolding proteins that modulate diverse cell functions being able to assemble signalling complexes. In this study, the presence, sub-cellular distribution and function of Homer 1 was investigated. Homer 1a and Homer 1b/c are constitutively expressed in cardiac muscle of both mouse and rat and in HL-1 cells, a cardiac cell line. As judged by confocal immunofluorescence microscopy, Homer 1a displays sarcomeric and peri-nuclear localization. In cardiomyocytes and cultured HL-1 cells, the hypertrophic agonist norepinephrine (NE) induces α{sub 1}-adrenergic specific Homer 1a over-expression, with a two-to-three-fold increase within 1 h, and no up-regulation of Homer 1b/c, as judged by Western blot and qPCR. In HL-1 cells, plasmid-driven over-expression of Homer 1a partially antagonizes activation of ERK phosphorylation and ANF up-regulation, two well-established, early markers of hypertrophy. At the morphometric level, NE-induced increase of cell size is likewise and partially counteracted by exogenous Homer 1a. Under the same experimental conditions, Homer 1b/c does not have any effect on ANF up-regulation nor on cell hypertrophy. Thus, Homer 1a up-regulation is associated to early stages of cardiac hypertrophy and appears to play a negative feedback regulation on molecular transducers of hypertrophy. -- Highlights: • Homer 1a is constitutively expressed in cardiac tissue. • In HL-1 cells, norepinephrine activates signaling pathways leading to hypertrophy. • Homer 1a up-regulation is an early event of norepinephrine-induced hypertrophy. • Homer 1a plays a negative feedback regulation modulating pathological hypertrophy. • Over-expression of Homer 1a per se does not induce hypertrophy.

Negative feedback regulation of Homer 1a on norepinephrine-dependent cardiac hypertrophy

International Nuclear Information System (INIS)

Chiarello, Carmelina; Bortoloso, Elena; Carpi, Andrea; Furlan, Sandra; Volpe, Pompeo

2013-01-01

Homers are scaffolding proteins that modulate diverse cell functions being able to assemble signalling complexes. In this study, the presence, sub-cellular distribution and function of Homer 1 was investigated. Homer 1a and Homer 1b/c are constitutively expressed in cardiac muscle of both mouse and rat and in HL-1 cells, a cardiac cell line. As judged by confocal immunofluorescence microscopy, Homer 1a displays sarcomeric and peri-nuclear localization. In cardiomyocytes and cultured HL-1 cells, the hypertrophic agonist norepinephrine (NE) induces α 1 -adrenergic specific Homer 1a over-expression, with a two-to-three-fold increase within 1 h, and no up-regulation of Homer 1b/c, as judged by Western blot and qPCR. In HL-1 cells, plasmid-driven over-expression of Homer 1a partially antagonizes activation of ERK phosphorylation and ANF up-regulation, two well-established, early markers of hypertrophy. At the morphometric level, NE-induced increase of cell size is likewise and partially counteracted by exogenous Homer 1a. Under the same experimental conditions, Homer 1b/c does not have any effect on ANF up-regulation nor on cell hypertrophy. Thus, Homer 1a up-regulation is associated to early stages of cardiac hypertrophy and appears to play a negative feedback regulation on molecular transducers of hypertrophy. -- Highlights: • Homer 1a is constitutively expressed in cardiac tissue. • In HL-1 cells, norepinephrine activates signaling pathways leading to hypertrophy. • Homer 1a up-regulation is an early event of norepinephrine-induced hypertrophy. • Homer 1a plays a negative feedback regulation modulating pathological hypertrophy. • Over-expression of Homer 1a per se does not induce hypertrophy

Early-Onset X-Linked Retinitis Pigmentosa in a Heterozygous Female Harboring an Intronic Donor Splice Site Mutation in the Retinitis Pigmentosa GTPase Regulator Gene.

Science.gov (United States)

Shifera, Amde Selassie; Kay, Christine Nichols

2015-01-01

To report a heterozygous female presenting with an early-onset and severe form of X-linked retinitis pigmentosa (XLRP). This is a case series presenting the clinical findings in a heterozygous female with XLRP and two of her family members. Fundus photography, fundus autofluorescence, ocular coherence tomography, and visual perimetry are presented. The proband reported here is a heterozygous female who presented at the age of 8 years with an early onset and aggressive form of XLRP. The patient belongs to a four-generation family with a total of three affected females and four affected males. The patient was initially diagnosed with retinitis pigmentosa (RP) at the age of 4 years. Genetic testing identified a heterozygous donor splice site mutation in intron 1 (IVS1 + 1G > A) of the retinitis pigmentosa GTPase regulator gene. The father of the proband was diagnosed with RP when he was a young child. The sister of the proband, evaluated at the age of 6 years, showed macular pigmentary changes. Although carriers of XLRP are usually asymptomatic or have a mild disease of late onset, the proband presented here exhibited an early-onset, aggressive form of the disease. It is not clear why some carrier females manifest a severe phenotype. A better understanding of the genetic processes involved in the penetrance and expressivity of XLRP in heterozygous females could assist in providing the appropriate counseling to affected families.

Developmental consequences of early parenting experiences: self-recognition and self-regulation in three cultural communities.

Science.gov (United States)

Keller, Heidi; Yovsi, Relindis; Borke, Joern; Kärtner, Joscha; Jensen, Henning; Papaligoura, Zaira

2004-01-01

This study relates parenting of 3-month-old children to children's self-recognition and self-regulation at 18 to 20 months. As hypothesized, observational data revealed differences in the sociocultural orientations of the 3 cultural samples' parenting styles and in toddlers' development of self-recognition and self-regulation. Children of Cameroonian Nso farmers who experience a proximal parenting style develop self-regulation earlier, children of Greek urban middle-class families who experience a distal parenting style develop self-recognition earlier, and children of Costa Rican middle-class families who experience aspects of both distal and proximal parenting styles fall between the other 2 groups on both self-regulation and self-recognition. Results are discussed with respect to their implications for culturally informed developmental pathways.

Regulation on control of nuclear fuel materials

International Nuclear Information System (INIS)

Ikeda, Kaname

1976-01-01

Some comment is made on the present laws and the future course of consolidating the regulation of nuclear fuel materials. The first part gives the definitions of the nuclear fuel materials in the laws. The second part deals with the classification and regulation in material handling. Refinement undertaking, fabrication undertaking, reprocessing undertaking, the permission of the government to use the materials, the permission of the government to use the materials under international control, the restriction of transfer and receipt, the reporting, and the safeguard measures are commented. The third part deals with the strengthening of regulation. The nuclear fuel safety deliberation special committee will be established at some opportunity of revising the ordinance. The nuclear material safeguard special committee has been established in the Atomic Energy Commission. The last part deals with the future course of legal consolidation. The safety control will be strengthened. The early investigation of waste handling is necessary, because low level solid wastes are accumulating at each establishment. The law for transporting nuclear materials must be consolidated as early as possible to correspond to foreign transportation laws. Physical protection is awaiting the conclusions of the nuclear fuel safeguard special committee. The control and information systems for the safeguard measures must be consolidated in the laws. (Iwakiri, K.)

Predicting Early Spelling: The Contribution of Children's Early Literacy, Private Speech during Spelling, Behavioral Regulation, and Parental Spelling Support

Science.gov (United States)

Aram, Dorit; Abiri, Shimrit; Elad, Lili

2014-01-01

The present study aimed to extend understanding of preschoolers' early spelling using the Vygotskian ("Mind in society: the development of higher psychological processes," Cambridge, Harvard University Press, 1978) paradigm of child development. We assessed the contribution of maternal spelling support in predicting children's word…

Regulation of behaviour by the nuclear receptor TLX.

Science.gov (United States)

O'Leary, J D; O'Leary, O F; Cryan, J F; Nolan, Y M

2018-03-01

The orphan nuclear receptor Tlx (Nr2e1) is a key regulator of both embryonic and adult hippocampal neurogenesis. Several different mouse models have been developed which target Tlx in vivo including spontaneous deletion models (from birth) and targeted and conditional knockouts. Although some conflicting findings have been reported, for the most part studies have demonstrated that Tlx is important in regulating processes that underlie neurogenesis, spatial learning, anxiety-like behaviour and interestingly, aggression. More recent data have demonstrated that disrupting Tlx during early life induces hyperactivity and that Tlx plays a role in emotional regulation. Moreover, there are sex- and age-related differences in some behaviours in Tlx knockout mice during adolescence and adulthood. Here, we discuss the role of Tlx in motor-, cognitive-, aggressive- and anxiety-related behaviours during adolescence and adulthood. We examine current evidence which provides insight into Tlx during neurodevelopment, and offer our thoughts on the function of Tlx in brain and behaviour. We further hypothesize that Tlx is a key target in understanding the emergence of neurobiological disorders during adolescence and early adulthood. © 2016 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Academic Motivation and Self-Regulated Learning in Predicting Academic Achievement in College

Science.gov (United States)

Çetin, Baris

2015-01-01

The purpose of this study was to determine whether academic motivation and academic self-regulated learning predicted students' GPAs in the Early Childhood Education Department. The study participants consisted of 166 early childhood education majors enrolled in the 2014 spring semester at Georgia Southern University, USA. Data were gathered using…

Implicit conditioning of faces via the social regulation of emotion: ERP evidence of early attentional biases for security conditioned faces.

Science.gov (United States)

Beckes, Lane; Coan, James A; Morris, James P

2013-08-01

Not much is known about the neural and psychological processes that promote the initial conditions necessary for positive social bonding. This study explores one method of conditioned bonding utilizing dynamics related to the social regulation of emotion and attachment theory. This form of conditioning involves repeated presentations of negative stimuli followed by images of warm, smiling faces. L. Beckes, J. Simpson, and A. Erickson (2010) found that this conditioning procedure results in positive associations with the faces measured via a lexical decision task, suggesting they are perceived as comforting. This study found that the P1 ERP was similarly modified by this conditioning procedure and the P1 amplitude predicted lexical decision times to insecure words primed by the faces. The findings have implications for understanding how the brain detects supportive people, the flexibility and modifiability of early ERP components, and social bonding more broadly. Copyright © 2013 Society for Psychophysiological Research.

Fatty Acid–Regulated Transcription Factors in the Liver