scholarly journals Electrical activity controls area-specific expression of neuronal apoptosis in the mouse developing cerebral cortex

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Oriane Blanquie ◽  
Jenq-Wei Yang ◽  
Werner Kilb ◽  
Salim Sharopov ◽  
Anne Sinning ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Primary Motor Cortex ◽  
Sensory Deprivation ◽  
Activity Patterns ◽  
Postnatal Period ◽  
Dependent Manner ◽  
Specific Expression ◽  
Neuronal Identity ◽  
Functional Maturation ◽  
Dependent Processes

Programmed cell death widely but heterogeneously affects the developing brain, causing the loss of up to 50% of neurons in rodents. However, whether this heterogeneity originates from neuronal identity and/or network-dependent processes is unknown. Here, we report that the primary motor cortex (M1) and primary somatosensory cortex (S1), two adjacent but functionally distinct areas, display striking differences in density of apoptotic neurons during the early postnatal period. These differences in rate of apoptosis negatively correlate with region-dependent levels of activity. Disrupting this activity either pharmacologically or by electrical stimulation alters the spatial pattern of apoptosis and sensory deprivation leads to exacerbated amounts of apoptotic neurons in the corresponding functional area of the neocortex. Thus, our data demonstrate that spontaneous and periphery-driven activity patterns are important for the structural and functional maturation of the neocortex by refining the final number of cortical neurons in a region-dependent manner.

Structured spike series specify gene expression patterns for olfactory circuit formation

Science ◽  
2019 ◽  
Vol 365 (6448) ◽  
pp. eaaw5030 ◽  
Author(s):  
Ai Nakashima ◽  
Naoki Ihara ◽  
Mayo Shigeta ◽  
Hiroshi Kiyonari ◽  
Yuji Ikegaya ◽  
...  
Keyword(s):  
Spontaneous Activity ◽  
Neural Activity ◽  
Activity Patterns ◽  
Expression Patterns ◽  
Temporal Patterns ◽  
Dependent Manner ◽  
Specific Expression ◽  
Circuit Formation ◽  
Combinatorial Code ◽  
Olfactory Map

Neural circuits emerge through the interplay of genetic programming and activity-dependent processes. During the development of the mouse olfactory map, axons segregate into distinct glomeruli in an olfactory receptor (OR)–dependent manner. ORs generate a combinatorial code of axon-sorting molecules whose expression is regulated by neural activity. However, it remains unclear how neural activity induces OR-specific expression patterns of axon-sorting molecules. We found that the temporal patterns of spontaneous neuronal spikes were not spatially organized but were correlated with the OR types. Receptor substitution experiments demonstrated that ORs determine spontaneous activity patterns. Moreover, optogenetically differentiated patterns of neuronal activity induced specific expression of the corresponding axon-sorting molecules and regulated axonal segregation. Thus, OR-dependent temporal patterns of spontaneous activity play instructive roles in generating the combinatorial code of axon-sorting molecules during olfactory map formation.

scholarly journals Cortical and Striatal Electroencephalograms and Apomorphine Effects in the FUS Mouse Model of Amyotrophic Lateral Sclerosis

2021 ◽  
pp. 1-15
Author(s):  
Vasily Vorobyov ◽  
Alexander Deev ◽  
Frank Sengpiel ◽  
Vladimir Nebogatikov ◽  
Aleksey A. Ustyugov
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Motor Neurons ◽  
Cortical Neurons ◽  
Primary Motor Cortex ◽  
Beta Activity ◽  
Systemic Injection ◽  
Eeg Spectra ◽  
Electroencephalogram Eeg ◽  
Lateral Sclerosis

Background: Amyotrophic lateral sclerosis (ALS) is characterized by degeneration of motor neurons resulting in muscle atrophy. In contrast to the lower motor neurons, the role of upper (cortical) neurons in ALS is yet unclear. Maturation of locomotor networks is supported by dopaminergic (DA) projections from substantia nigra to the spinal cord and striatum. Objective: To examine the contribution of DA mediation in the striatum-cortex networks in ALS progression. Methods: We studied electroencephalogram (EEG) from striatal putamen (Pt) and primary motor cortex (M1) in ΔFUS(1–359)-transgenic (Tg) mice, a model of ALS. EEG from M1 and Pt were recorded in freely moving young (2-month-old) and older (5-month-old) Tg and non-transgenic (nTg) mice. EEG spectra were analyzed for 30 min before and for 60 min after systemic injection of a DA mimetic, apomorphine (APO), and saline. Results: In young Tg versus nTg mice, baseline EEG spectra in M1 were comparable, whereas in Pt, beta activity in Tg mice was enhanced. In older Tg versus nTg mice, beta dominated in EEG from both M1 and Pt, whereas theta and delta 2 activities were reduced. In younger Tg versus nTg mice, APO increased theta and decreased beta 2 predominantly in M1. In older mice, APO effects in these frequency bands were inversed and accompanied by enhanced delta 2 and attenuated alpha in Tg versus nTg mice. Conclusion: We suggest that revealed EEG modifications in ΔFUS(1–359)-transgenic mice are associated with early alterations in the striatum-cortex interrelations and DA transmission followed by adaptive intracerebral transformations.

scholarly journals Cortical neurons exhibit diverse myelination patterns that scale between mouse brain regions and regenerate after demyelination

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Cody L. Call ◽  
Dwight E. Bergles
Keyword(s):  
Cortical Neurons ◽  
Regional Differences ◽  
Brain Regions ◽  
Axon Diameter ◽  
Neuronal Identity ◽  
Cortical Areas ◽  
Myelin Sheaths ◽  
Parvalbumin Interneurons ◽  
Selection Of

ABSTRACTAxons in the cerebral cortex show a broad range of myelin coverage. Oligodendrocytes establish this pattern by selecting a cohort of axons for myelination; however, the distribution of myelin on distinct neurons and extent of internode replacement after demyelination remain to be defined. Here we show that myelination patterns of seven distinct neuron subtypes in somatosensory cortex are influenced by both axon diameter and neuronal identity. Preference for myelination of parvalbumin interneurons was preserved between cortical areas with varying myelin density, suggesting that regional differences in myelin abundance arises through local control of oligodendrogenesis. By imaging loss and regeneration of myelin sheaths in vivo we show that myelin distribution on individual axons was altered but overall myelin content on distinct neuron subtypes was restored. Our findings suggest that local changes in myelination are tolerated, allowing regenerated oligodendrocytes to restore myelin content on distinct neurons through opportunistic selection of axons.

scholarly journals Using Brain Activity Patterns to Differentiate Real and Virtual Attended Targets during Augmented Reality Scenarios

Information ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 226
Author(s):  
Lisa-Marie Vortmann ◽  
Leonid Schwenke ◽  
Felix Putze
Keyword(s):  
Augmented Reality ◽  
Eye Tracking ◽  
Brain Activity ◽  
Activity Patterns ◽  
Training Data ◽  
Machine Learning Techniques ◽  
Neural Net ◽  
Dependent Manner ◽  
Tracking Data ◽  
Average Accuracy

Augmented reality is the fusion of virtual components and our real surroundings. The simultaneous visibility of generated and natural objects often requires users to direct their selective attention to a specific target that is either real or virtual. In this study, we investigated whether this target is real or virtual by using machine learning techniques to classify electroencephalographic (EEG) and eye tracking data collected in augmented reality scenarios. A shallow convolutional neural net classified 3 second EEG data windows from 20 participants in a person-dependent manner with an average accuracy above 70% if the testing data and training data came from different trials. This accuracy could be significantly increased to 77% using a multimodal late fusion approach that included the recorded eye tracking data. Person-independent EEG classification was possible above chance level for 6 out of 20 participants. Thus, the reliability of such a brain–computer interface is high enough for it to be treated as a useful input mechanism for augmented reality applications.

scholarly journals The Carbamate, Physostigmine does not Impair Axonal Transport in Rat Cortical Neurons

2021 ◽  
Vol 16 ◽  
pp. 263310552110202
Author(s):  
Sean X Naughton ◽  
Wayne D Beck ◽  
Zhe Wei ◽  
Guangyu Wu ◽  
Peter W Baas ◽  
...  
Keyword(s):  
Axonal Transport ◽  
Cortical Neurons ◽  
Acetylcholinesterase Inhibitors ◽  
Neurological Deficits ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Rat Cortical Neurons ◽  
Toxicological Mechanism

Among the various chemicals that are commonly used as pesticides, organophosphates (OPs), and to a lesser extent, carbamates, are most frequently associated with adverse long-term neurological consequences. OPs and the carbamate, pyridostigmine, used as a prophylactic drug against potential nerve agent attacks, have also been implicated in Gulf War Illness (GWI), which is often characterized by chronic neurological symptoms. While most OP- and carbamate-based pesticides, and pyridostigmine are relatively potent acetylcholinesterase inhibitors (AChEIs), this toxicological mechanism is inadequate to explain their long-term health effects, especially when no signs of acute cholinergic toxicity are exhibited. Our previous work suggests that a potential mechanism of the long-term neurological deficits associated with OPs is impairment of axonal transport (AXT); however, we had not previously evaluated carbamates for this effect. Here we thus evaluated the carbamate, physostigmine (PHY), a highly potent AChEI, on AXT using an in vitro neuronal live imaging assay that we have previously found to be very sensitive to OP-related deficits in AXT. We first evaluated the OP, diisopropylfluorophosphate (DFP) (concentration range 0.001-10.0 µM) as a reference compound that we found previously to impair AXT and subsequently evaluated PHY (concentration range 0.01-100 nM). As expected, DFP impaired AXT in a concentration-dependent manner, replicating our previously published results. In contrast, none of the concentrations of PHY (including concentrations well above the threshold for impairing AChE) impaired AXT. These data suggest that the long-term neurological deficits associated with some carbamates are not likely due to acute impairments of AXT.

Abstract 17112: Transgenic Endothelial-Specific HIV-Nef Expression Induces Pulmonary Hypertension and Systemic Vascular Dysfunction, Which Can Be Reverted by Treatment With Statin

Circulation ◽  
2018 ◽  
Vol 138 (Suppl_1) ◽  
Author(s):  
Natalia Bogatcheva ◽  
Sarvesh Chelvanambi ◽  
Xingjuan Chen ◽  
Alexander Obukhov ◽  
Matthias Clauss
Keyword(s):  
Pulmonary Hypertension ◽  
Vascular Dysfunction ◽  
Vascular Diseases ◽  
Arterial Disease ◽  
Statin Treatment ◽  
Systemic Circulation ◽  
Vascular Pathology ◽  
Systemic Hypertension ◽  
Dependent Manner ◽  
Specific Expression

Introduction: HIV patients on ART perplexingly remain at higher risk for developing cardiovascular diseases including acute peripheral arterial disease and pulmonary hypertension. A likely culprit for observed vascular changes is HIV protein Nef, detected both intracellularly and extracellularly in the absence of HIV RNA or DNA. Nef is known to induce endothelial dysfunction through the activation of NADPH; statins are known to inhibit NADPH activation. Hypothesis: Nef expression in endothelial cells will trigger cardiopulmonary and vascular pathology; Nef effects will be reversed by statin. Methods: Endothelial-specific expression of HIV-Nef was achieved by mating the VE-Cadherin-Tet off mice with TRE-Nef mice. The resulting Nef+ double transgenics and their Nef- negative littermates were maintained without doxycycline to induce Nef expression. Changes in pulmonary acceleration and ejection times were analyzed by ultrasound (INVEVO2100). Additionally, we assessed the ability of bradykinin-preconstricted aortic rings to dilate in response to acetylcholine in NO-dependent manner. Results: Between week 10 and week 13 of age, Nef expressing mice displayed gradual reduction of PAT/PET ratio (down to the 75% of the original PAT/PET ratio at week 10), indicative of developing pulmonary hypertension (N=6). PAT/PET ratio in Nef-negative mice did not change significantly between week 10 and 13 of age. Importantly, statin treatment initiated at week 10 completely suppressed PAT/PET changes developing in Nef-expressing mice. Arterial rings from Nef expressing mice (n=4) showed significantly impaired dilatation in response to acetylcholine (10% relaxation in Nef+ mice vs 40% relaxation in Nef-negative littermates, p=0.03), indicative of changes in systemic circulation. This difference was significantly attenuated in Nef+ mice receiving statin treatment. Conclusions: Our data suggests that mice with endothelial expression of HIV-Nef display pathological changes in pulmonary and systemic circulation. Statin treatment significantly attenuates changes in parameters indicative of pulmonary and systemic hypertension, suggesting that statin will be beneficial for patients with HIV-induced cardiopulmonary and vascular diseases.

scholarly journals 0128 SENSORY DEPRIVATION SUPPRESSES CORTICAL ACTIVITY IN A STATE AND ENVIRONMENT DEPENDENT MANNER

SLEEP ◽  
2017 ◽  
Vol 40 (suppl_1) ◽  
pp. A48-A48
Author(s):  
KB Hengen ◽  
A Torrado Pacheco ◽  
GG Turrigiano
Keyword(s):  
Sensory Deprivation ◽  
Cortical Activity ◽  
Dependent Manner

Effects of 5-HT on thalamocortical synaptic transmission in the developing rat

1994 ◽  
Vol 72 (5) ◽  
pp. 2438-2450 ◽  
Author(s):  
R. W. Rhoades ◽  
C. A. Bennett-Clarke ◽  
M. Y. Shi ◽  
R. D. Mooney
Keyword(s):  
Synaptic Transmission ◽  
Somatosensory Cortex ◽  
Cortical Neurons ◽  
Input Resistance ◽  
Inhibitory Effect ◽  
Primary Somatosensory Cortex ◽  
Excitatory Postsynaptic Potential ◽  
Dependent Manner ◽  
Cortical Cells ◽  
Thalamocortical Axons

1. Recent immunocytochemical and receptor binding data have demonstrated a transient somatotopic patterning of serotonin (5-HT)-immunoreactive fibers in the primary somatosensory cortex of developing rats and a transient expression of 5-HT1B receptors on thalamocortical axons from the ventral posteromedial thalamic nucleus (VPM). 2. These results suggest that 5-HT should strongly modulate thalamocortical synaptic transmission for a limited time during postnatal development. This hypothesis was tested in intracellular recording experiments carried out in thalamocortical slice preparations that included VPM, the thalamic radiations, and the primary somatosensory cortex. Effects of 5-HT and analogues were monitored on membrane potentials and input resistances of cortical neurons and on the amplitude of the synaptic potentials evoked in them by stimulation of VPM. 3. Results obtained from cortical neurons in slices taken from rats during the first 2 wk of life indicated that 5-HT strongly inhibited the VPM-evoked excitatory postsynaptic potential (EPSP) recorded from cortical neurons in a dose-dependent manner. In contrast, 5-HT had no significant effects on membrane potential, input resistance, or depolarizations induced by direct application of glutamic acid to cortical cells. 4. The effects of 5-HT were mimicked by the 5-HT1B receptor agonists 1-[3-(trifluoromethyl)phenyl]-piperazine (TFMPP) and 7-trifluoromethyl-4(4-methyl-1-piperazinyl)-pyrrolo[1,2-a]-quinoxaline maleate and antagonized by the 5-HT1B receptor antagonist (-)-pindolol. The 5-HT1A agonist [(+/-)8-hydroxydipropylaminotetralin HBr] (8-OH-DPAT) had less effect on the VPM-elicited EPSP, and the effects of 5-HT upon this response were generally not antagonized by either 1-(2-methoxyphenyl)-4-[4-(2- phthalimmido)butyl]piperazine HBr (a 5-HT1A antagonist) or ketanserine (a 5-HT2 antagonist) or spiperone (a 5-HT1A and 2 antagonist). 5. The ability of 5-HT to inhibit the VPM-evoked EPSP in cortical neurons was significantly reduced in slices from animals > 2 wk of age. The effectiveness of TFMPP in such animals was even more attenuated than that of 5-HT, and the effectiveness of 8-OH-DPAT was unchanged with age. These results are consistent with the disappearance of 5-HT1B receptors from thalamocortical axons after the second postnatal week and the maintenance of 5-HT1A receptors on some neurons. 6. All of the results obtained in this study are consistent with the conclusion that 5-HT has a profound, but developmentally transient, presynaptic inhibitory effect upon thalamocortical transmission in the rat's somatosensory cortex.

scholarly journals Apamin Enhances Neurite Outgrowth and Regeneration after Laceration Injury in Cortical Neurons

Toxins ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 603
Author(s):  
Hyunseong Kim ◽  
Jin Young Hong ◽  
Junseon Lee ◽  
Wan-Jin Jeon ◽  
In-Hyuk Ha
Keyword(s):  
Phospholipase A2 ◽  
Neurite Outgrowth ◽  
Cortical Neurons ◽  
Neurological Diseases ◽  
Minor Component ◽  
Underlying Mechanism ◽  
Bee Venom ◽  
Dependent Manner ◽  
Neuroprotective Effects ◽  
Wide Range

Apamin is a minor component of bee venom and is a polypeptide with 18 amino acid residues. Although apamin is considered a neurotoxic compound that blocks the potassium channel, its neuroprotective effects on neurons have been recently reported. However, there is little information about the underlying mechanism and very little is known regarding the toxicological characterization of other compounds in bee venom. Here, cultured mature cortical neurons were treated with bee venom components, including apamin, phospholipase A2, and the main component, melittin. Melittin and phospholipase A2 from bee venom caused a neurotoxic effect in dose-dependent manner, but apamin did not induce neurotoxicity in mature cortical neurons in doses of up to 10 µg/mL. Next, 1 and 10 µg/mL of apamin were applied to cultivate mature cortical neurons. Apamin accelerated neurite outgrowth and axon regeneration after laceration injury. Furthermore, apamin induced the upregulation of brain-derived neurotrophic factor and neurotrophin nerve growth factor, as well as regeneration-associated gene expression in mature cortical neurons. Due to its neurotherapeutic effects, apamin may be a promising candidate for the treatment of a wide range of neurological diseases.

scholarly journals All-Trans Retinoic Acid induces synaptic plasticity in human cortical neurons

2020 ◽  
Author(s):  
Maximilian Lenz ◽  
Pia Kruse ◽  
Amelie Eichler ◽  
Julia Muellerleile ◽  
Jakob Straehle ◽  
...  
Keyword(s):  
Retinoic Acid ◽  
Synaptic Plasticity ◽  
Cortical Neurons ◽  
Mrna Translation ◽  
Dependent Manner ◽  
Human Cortex ◽  
Functional Changes ◽  
Trans Retinoic Acid ◽  
All Trans Retinoic Acid ◽  
Structural And Functional Properties

ABSTRACTA defining feature of the brain is its ability to adapt structural and functional properties of synaptic contacts in an experience-dependent manner. In the human cortex direct experimental evidence for synaptic plasticity is currently missing. Here, we probed plasticity in human cortical slices using the vitamin A derivative all-trans retinoic acid, which has been suggested as medication for the treatment of neuropsychiatric disorders, e.g., Alzheimer’s disease. Our experiments demonstrate coordinated structural and functional changes of excitatory synapses of superficial (layer 2/3) pyramidal neurons in the presence of all-trans retinoic acid. This synaptic adaptation is accompanied by ultrastructural remodeling of the calcium-storing spine apparatus organelle and requires mRNA-translation. We conclude that all-trans retinoic acid is a potent mediator of synaptic plasticity in the adult human cortex.

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