Molecular mechanisms of non-transferrin-bound and transferring-bound iron uptake in primary hippocampal neurons

Objective: Corticosterone causes significant neurotoxicity in primary hippocampal neurons which is associated with depression. Dysfunctional autophagy is implicated in cognitive impairment and depressive-like behavior. The traditional Chinese medicine Sinisan (SNS) is highly effective in clinical treatment of depression. However, the molecular mechanisms underlying therapeutic effects of SNS are unknown.Purpose: The aim of this study was to elucidate the protective effect of SNS and the underlying mechanisms against corticosterone-induced neuronal damage.Study Design: The effects of serum derived from rats containing SNS (or untreated controls) on the expression of autophagy-related molecules in primary rat hippocampal neurons exposed to different concentrations of corticosterone for different intervals were explored.Methods: CCK-8 assay, LDH assay were used to analyze cell viability and LDH activity. Western blot, qRT-PCR, and immunofluorescence assays were used to determine protein and mRNA expression levels of molecules such as LC3, p62, Beclin1, ULK1, PI3K, p-PI3K, Akt p-Akt, mTOR, p-mTOR, p70S6, p-p70S6, 4ebp1 and p-4ebp1.Results: Corticosterone induced a dose- and time-dependent reduction in cellular viability. Moreover, corticosterone (100–400 μM) treatment for 24 h increased LC3-II/LC3-I protein ratio, increased Beclin1 and ULK1 protein expression levels, and decreased p62, PI3K, p-PI3K, p-Akt, p-mTOR, p-p70S6, and p-4ebp1 protein expression levels. Notably, SNS-containing serum reversed corticosterone-induced reduction of neuronal viability, and increased p62, PI3K, p-Akt, p-mTOR, p-p70S6, and p-4ebp1 protein and mRNA expression levels. In addition, SNS-containing serum decreased LC3-II/LC3-I protein ratio, and downregulated Beclin1, and ULK1 protein and mRNA expression in primary hippocampal neurons.Conclusion: SNS protects primary hippocampal neurons against corticosterone-induced neurotoxicity by preventing excessive autophagy through activation of PI3K/AKT/mTOR pathway.

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Metformin attenuates LPS-induced neuronal injury and cognitive impairments by blocking NF-κB pathway

BMC Neuroscience ◽

10.1186/s12868-021-00678-5 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Chenliang Zhou ◽

Bo Peng ◽

Zhenghui Qin ◽

Wei Zhu ◽

Cuiping Guo

Keyword(s):

Synaptic Plasticity ◽

Signaling Pathway ◽

Hippocampal Neurons ◽

Molecular Mechanisms ◽

Inflammatory Responses ◽

Neuronal Damage ◽

Cognitive Impairments ◽

Neuronal Injury ◽

Sd Rats ◽

Primary Hippocampal Neurons

Abstract Background Neuroinflammatory response is considered to be a high-risk factor for cognitive impairments in the brain. Lipopolysaccharides (LPS) is an endotoxin that induces acute inflammatory responses in injected bodies. However, the molecular mechanisms underlying LPS-associated cognitive impairments still remain unclear. Methods Here, primary hippocampal neurons were treated with LPS, and western blotting and immunofluorescence were used to investigate whether LPS induces neurons damage. At the same time, SD rats were injected with LPS (830 μg/Kg) intraperitoneally, and Open field test, Novel Objective Recognition test, Fear condition test were used to detect cognitive function. LTP was used to assess synaptic plasticity, and molecular biology technology was used to assess the NF-κB pathway, while ELISA was used to detect inflammatory factors. In addition, metformin was used to treat primary hippocampal neurons, and intraventricularly administered to SD rats. The same molecular technics, behavioral and electrophysiological tests were used to examine whether metformin could alleviate the LPS-associated neuronal damage, as well as synaptic plasticity, and behavioral alterations in SD rats. Results Altogether, neuronal damage were observed in primary hippocampal neurons after LPS intervention, which were alleviated by metformin treatment. At the same time, LPS injection in rat triggers cognitive impairment through activation of NF-κB signaling pathway, and metformin administration alleviates the LPS-induced memory dysfunction and improves synaptic plasticity. Conclusion These findings highlight a novel pathogenic mechanism of LPS-related cognitive impairments through activation of NF-κB signaling pathway, and accumulation of inflammatory mediators, which induces neuronal pathologic changes and cognitive impairments. However, metformin attenuates LPS-induced neuronal injury and cognitive impairments by blocking NF-κB pathway.

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ATRA-induced increase in intracellular Ca2+concentration in primary hippocampal neurons

Cell Biology International ◽

10.1042/cbi034s074b ◽

2010 ◽

Vol 34 (8) ◽

pp. S74-S74

Author(s):

Tingyu Li ◽

Xiaojuan Zhang ◽

Xuan Zhang ◽

Jian Hea ◽

Yang Bi Youxue Liu ◽

...

Keyword(s):

Hippocampal Neurons ◽

Primary Hippocampal Neurons

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Schisandrin Restores the Amyloid β-Induced Impairments on Mitochondrial Function, Energy Metabolism, Biogenesis, and Dynamics in Rat Primary Hippocampal Neurons

Pharmacology ◽

10.1159/000507818 ◽

2021 ◽

pp. 1-11

Author(s):

Zhongyuan Piao ◽

Lin Song ◽

Lifen Yao ◽

Limei Zhang ◽

Yichan Lu

Keyword(s):

Energy Metabolism ◽

Cytochrome C ◽

Mitochondrial Biogenesis ◽

Mitochondrial Function ◽

Hippocampal Neurons ◽

Citrate Synthase ◽

Mitochondrial Permeability Transition ◽

Amyloid Β ◽

Mitochondrial Functions ◽

Primary Hippocampal Neurons

Introduction: Schisandrin which is derived from Schisandra chinensis has shown multiple pharmacological effects on various diseases including Alzheimer’s disease (AD). It is demonstrated that mitochondrial dysfunction plays an essential role in the pathogenesis of neurodegenerative disorders. Objective: Our study aims to investigate the effects of schisandrin on mitochondrial functions and metabolisms in primary hippocampal neurons. Methods: In our study, rat primary hippocampal neurons were isolated and treated with indicated dose of amyloid β1–42 (Aβ1–42) oligomer to establish a cell model of AD in vitro. Schisandrin (2 μg/mL) was further subjected to test its effects on mitochondrial function, energy metabolism, mitochondrial biogenesis, and dynamics in the Aβ1–42 oligomer-treated neurons. Results and Conclusions: Our findings indicated that schisandrin significantly alleviated the Aβ1–42 oligomer-induced loss of mitochondrial membrane potential and impaired cytochrome c oxidase activity. Additionally, the opening of mitochondrial permeability transition pore and release of cytochrome c were highly restricted with schisandrin treatment. Alterations in cell viability, ATP production, citrate synthase activity, and the expressions of glycolysis-related enzymes demonstrated the relief of defective energy metabolism in Aβ-treated neurons after the treatment of schisandrin. For mitochondrial biogenesis, elevated expression of peroxisome proliferator-activated receptor γ coactivator along with promoted mitochondrial mass was found in schisandrin-treated cells. The imbalance in the cycle of fusion and fission was also remarkably restored by schisandrin. In summary, this study provides novel mechanisms for the protective effect of schisandrin on mitochondria-related functions.

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Cdc42 Facilitates Axonogenesis by Enhancing Microtubule Stabilization in Primary Hippocampal Neurons

Cellular and Molecular Neurobiology ◽

10.1007/s10571-021-01051-0 ◽

2021 ◽

Author(s):

Ang Li ◽

Hui-Ming Zhu ◽

Yu Chen ◽

Fang Yan ◽

Zhong-Ying Liu ◽

...

Keyword(s):

Hippocampal Neurons ◽

Microtubule Stabilization ◽

Primary Hippocampal Neurons

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Neurotrophic Properties of Silexan, an Essential Oil from the Flowers of Lavender-Preclinical Evidence for Antidepressant-Like Properties

Pharmacopsychiatry ◽

10.1055/a-1293-8585 ◽

2020 ◽

Vol 54 (01) ◽

pp. 37-46

Author(s):

Kristina Friedland ◽

Giacomo Silani ◽

Anita Schuwald ◽

Carola Stockburger ◽

Egon Koch ◽

...

Keyword(s):

Essential Oil ◽

Hippocampal Neurons ◽

Day Treatment ◽

Neuronal Cell ◽

Antidepressant Activity ◽

In Vivo Models ◽

Antidepressant Effects ◽

Primary Hippocampal Neurons

Abstract Background Silexan, a special essential oil from flowering tops of lavandula angustifolia, is used to treat subsyndromal anxiety disorders. In a recent clinical trial, Silexan also showed antidepressant effects in patients suffering from mixed anxiety-depression (ICD-10 F41.2). Since preclinical data explaining antidepressant properties of Silexan are missing, we decided to investigate if Silexan also shows antidepressant-like effects in vitro as well as in vivo models. Methods We used the forced swimming test (FST) in rats as a simple behavioral test indicative of antidepressant activity in vivo. As environmental events and other risk factors contribute to depression through converging molecular and cellular mechanisms that disrupt neuronal function and morphology—resulting in dysfunction of the circuitry that is essential for mood regulation and cognitive function—we investigated the neurotrophic properties of Silexan in neuronal cell lines and primary hippocampal neurons. Results The antidepressant activity of Silexan (30 mg/kg BW) in the FST was comparable to the tricyclic antidepressant imipramine (20 mg/kg BW) after 9-day treatment. Silexan triggered neurite outgrowth and synaptogenesis in 2 different neuronal cell models and led to a significant increase in synaptogenesis in primary hippocampal neurons. Silexan led to a significant phosphorylation of protein kinase A and subsequent CREB phosphorylation. Conclusion Taken together, Silexan demonstrates antidepressant-like effects in cellular as well as animal models for antidepressant activity. Therefore, our data provides preclinical evidence for the clinical antidepressant effects of Silexan in patients with mixed depression and anxiety.

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BDNF mobilizes synaptic vesicles and enhances synapse formation by disrupting cadherin–β-catenin interactions

The Journal of Cell Biology ◽

10.1083/jcb.200601087 ◽

2006 ◽

Vol 174 (2) ◽

pp. 289-299 ◽

Cited By ~ 115

Author(s):

Shernaz X. Bamji ◽

Beatriz Rico ◽

Nikole Kimes ◽

Louis F. Reichardt

Keyword(s):

Synaptic Vesicle ◽

Synaptic Vesicles ◽

Hippocampal Neurons ◽

Molecular Mechanisms ◽

Synapse Formation ◽

Time Lapse ◽

Synapse Density ◽

Vesicle Mobility ◽

Small Clusters ◽

Vertebrate Central Nervous System

Neurons of the vertebrate central nervous system have the capacity to modify synapse number, morphology, and efficacy in response to activity. Some of these functions can be attributed to activity-induced synthesis and secretion of the neurotrophin brain-derived neurotrophic factor (BDNF); however, the molecular mechanisms by which BDNF mediates these events are still not well understood. Using time-lapse confocal analysis, we show that BDNF mobilizes synaptic vesicles at existing synapses, resulting in small clusters of synaptic vesicles “splitting” away from synaptic sites. We demonstrate that BDNF's ability to mobilize synaptic vesicle clusters depends on the dissociation of cadherin–β-catenin adhesion complexes that occurs after tyrosine phosphorylation of β-catenin. Artificially maintaining cadherin–β-catenin complexes in the presence of BDNF abolishes the BDNF-mediated enhancement of synaptic vesicle mobility, as well as the longer-term BDNF-mediated increase in synapse number. Together, this data demonstrates that the disruption of cadherin–β-catenin complexes is an important molecular event through which BDNF increases synapse density in cultured hippocampal neurons.

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Impact of manganese on primary hippocampal neurons from rodents

Hippocampus ◽

10.1002/hipo.22252 ◽

2014 ◽

Vol 24 (5) ◽

pp. 598-610 ◽

Cited By ~ 12

Author(s):

Alexia Daoust ◽

Yasmina Saoudi ◽

Jacques Brocard ◽

Nora Collomb ◽

Cécile Batandier ◽

...

Keyword(s):

Hippocampal Neurons ◽

Primary Hippocampal Neurons

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Deletion of the Actin-Associated Tropomyosin Tpm3 Leads to Reduced Cell Complexity in Cultured Hippocampal Neurons—New Insights into the Role of the C-Terminal Region of Tpm3.1

Cells ◽

10.3390/cells10030715 ◽

2021 ◽

Vol 10 (3) ◽

pp. 715

Author(s):

Tamara Tomanić ◽

Claire Martin ◽

Holly Stefen ◽

Esmeralda Parić ◽

Peter Gunning ◽

...

Keyword(s):

Amino Acid ◽

Hippocampal Neurons ◽

Molecular Mechanisms ◽

Growth Cones ◽

Amino Acid Residues ◽

Terminal Amino Acid ◽

C Terminus ◽

Primary Mouse ◽

Terminal Amino

Tropomyosins (Tpms) have been described as master regulators of actin, with Tpm3 products shown to be involved in early developmental processes, and the Tpm3 isoform Tpm3.1 controlling changes in the size of neuronal growth cones and neurite growth. Here, we used primary mouse hippocampal neurons of C57/Bl6 wild type and Bl6Tpm3flox transgenic mice to carry out morphometric analyses in response to the absence of Tpm3 products, as well as to investigate the effect of C-terminal truncation on the ability of Tpm3.1 to modulate neuronal morphogenesis. We found that the knock-out of Tpm3 leads to decreased neurite length and complexity, and that the deletion of two amino acid residues at the C-terminus of Tpm3.1 leads to more detrimental changes in neurite morphology than the deletion of six amino acid residues. We also found that Tpm3.1 that lacks the 6 C-terminal amino acid residues does not associate with stress fibres, does not segregate to the tips of neurites, and does not impact the amount of the filamentous actin pool at the axonal growth cones, as opposed to Tpm3.1, which lacks the two C-terminal amino acid residues. Our study provides further insight into the role of both Tpm3 products and the C-terminus of Tpm3.1, and it forms the basis for future studies that aim to identify the molecular mechanisms underlying Tpm3.1 targeting to different subcellular compartments.

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