scholarly journals Calcium Export from Neurons and Multi-Kinase Signaling Cascades Contribute to Ouabain Neuroprotection in Hyperhomocysteinemia

Biomolecules ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1104
Author(s):  
Maria A. Ivanova ◽  
Arina D. Kokorina ◽  
Polina D. Timofeeva ◽  
Tatiana V. Karelina ◽  
Polina A. Abushik ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Primary Cultures ◽  
Glutamate Excitotoxicity ◽  
Neuroprotective Effects ◽  
Mediated Effects ◽  
Mitochondrial Inner Membrane ◽  
Rat Cortical Neurons ◽  
Proteinkinase C ◽  
Apoptosis Related Protein

Pathological homocysteine (HCY) accumulation in the human plasma, known as hyperhomocysteinemia, exacerbates neurodegenerative diseases because, in the brain, this amino acid acts as a persistent N-methyl-d-aspartate receptor agonist. We studied the effects of 0.1–1 nM ouabain on intracellular Ca2+ signaling, mitochondrial inner membrane voltage (φmit), and cell viability in primary cultures of rat cortical neurons in glutamate and HCY neurotoxic insults. In addition, apoptosis-related protein expression and the involvement of some kinases in ouabain-mediated effects were evaluated. In short insults, HCY was less potent than glutamate as a neurotoxic agent and induced a 20% loss of φmit, whereas glutamate caused a 70% decrease of this value. Subnanomolar ouabain exhibited immediate and postponed neuroprotective effects on neurons. (1) Ouabain rapidly reduced the Ca2+ overload of neurons and loss of φmit evoked by glutamate and HCY that rescued neurons in short insults. (2) In prolonged 24 h excitotoxic insults, ouabain prevented neuronal apoptosis, triggering proteinkinase A and proteinkinase C dependent intracellular neuroprotective cascades for HCY, but not for glutamate. We, therefore, demonstrated here the role of PKC and PKA involving pathways in neuronal survival caused by ouabain in hyperhomocysteinemia, which suggests existence of different appropriate pharmacological treatment for hyperhomocysteinemia and glutamate excitotoxicity.

scholarly journals Calcium export from neurons and multi-kinase signaling cascades contribute to ouabain neuroprotection in hyperhomocysteinemia

2020 ◽  
Author(s):  
Maria A. Ivanova ◽  
Arina D. Kokorina ◽  
Polina D. Timofeeva ◽  
Tatiana V. Karelina ◽  
Polina A. Abushik ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Intracellular Signaling ◽  
Primary Cultures ◽  
Membrane Voltage ◽  
Glutamate Excitotoxicity ◽  
Kinase Signaling ◽  
Neuroprotective Effects ◽  
Inner Membrane ◽  
Mitochondrial Inner Membrane ◽  
Voltage Loss

Abstract Background: Subnanomolar ouabain binding to the Na,K-ATPase triggers intracellular signaling, prevents an overload of neurons with Ca2+, and their apoptosis caused by glutamate receptor agonists. Elevated plasma homocysteine (HCY), known as hyperhomocysteinemia, represents a risk factor for stroke and can exacerbate many neuronal disorders. HCY acts as a persistent N-methyl-D-aspartate receptor (NMDAR) agonist, which, in contrast to glutamate, desensitizes NMDARs containing GluN2B subunits. Mechanisms of HCY neurotoxicity remain not clearly understood since GluN2B-containing NMDARs provide a major contribution to excitotoxicity among glutamate receptors.Methods: Using fluorescent tools combined with the confocal microscopy, we compared 0.1 - 1 nM ouabain effects on the intracellular Ca2+ signaling, on the mitochondrial inner membrane voltage and the cell viability in primary cultures of rat cortical neurons in glutamate and HCY neurotoxic insults. We also studied an apoptosis-related protein expression and the involvement of some kinases in ouabain mediated effects.Results: In short insults HCY was less potent than glutamate as a neurotoxic agent. This amino acid induced the voltage loss (∆φmit) of 0.2 of the total mitochondrial inner membrane voltage (φmit) instead of ∆φmit = 0.7 for glutamate. We have found that subnanomolar ouabain exhibited rapid and postponed neuroprotective effects on neurons and (1) rapidly reduced the Ca2+ overload of neurons and the voltage loss of inner mitochondrial membranes evoked by glutamate and HCY, and (2) prevented neuronal apoptosis during 24 h treatments with glutamate or HCY. Using a set of specific kinase inhibitors such as PKA inhibitor, chelerythrine, and KN93, we demonstrated the role of multi-kinase signaling pathways involving PKC and PKA in neuronal survival caused by ouabain in hyperhomocysteinemia. Conclusions: Subnanomolar ouabain prevents neurodegeneration caused by glutamate and HCY. For both amino acids, ouabain evokes an acceleration of Ca2+ export by sodium-calcium exchangers from neurons preventing the voltage loss by mitochondrial inner membranes that rescue neurons in short insults. In prolonged insults, ouabain triggers intracellular neuroprotective cascades, including activation of PKA and PKC for HCY, but not for glutamate. This suggests that different appropriate pharmacology for hyperhomocysteinemia and glutamate excitotoxicity could be applied for clinical treatments.

scholarly journals ROS-Independent Preconditioning in Neurons via Activation of mitoKATP Channels by BMS-191095

2008 ◽  
Vol 28 (6) ◽  
pp. 1090-1103 ◽  
Author(s):  
Tamás Gáspár ◽  
James A Snipes ◽  
Anna R Busija ◽  
Béla Kis ◽  
Ferenc Domoki ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Glycogen Synthase ◽  
Neuroprotective Effect ◽  
Primary Cultures ◽  
Brain Mitochondria ◽  
Glutamate Excitotoxicity ◽  
Ros Generation ◽  
Rat Cortical Neurons ◽  
Phosphoinositide 3 Kinase

Previously, we have shown that the selective mitochondrial ATP-sensitive potassium (mitoKATP) channel opener BMS-191095 (BMS) induces neuronal preconditioning (PC); however, the exact mechanism of BMS-induced neuroprotection remains unclear. In this study, we have identified key components of the cascade resulting in delayed neuronal PC with BMS using isolated rat brain mitochondria and primary cultures of rat cortical neurons. BMS depolarized isolated mitochondria without an increase in reactive oxygen species (ROS) generation and induced rapid phosphorylation of Akt and glycogen synthase kinase-3β. Long-term (3 days) treatment of neurons with BMS resulted in sustained mitochondrial depolarization, decreased basal ROS generation, and elevated ATP levels. This treatment also elicited almost complete protection against glutamate excitotoxicity, which could be abolished using the phosphoinositide 3-kinase (PI3K) inhibitor wortmannin, but not with the superoxide dismutase (SOD) mimetic M40401. Long-term BMS treatment induced a PI3K-dependent increase in the expression and activity of catalase without affecting manganese SOD and copper/zinc-dependent SOD. Finally, the catalase inhibitor 3-aminotriazole dose-dependently antagonized the neuroprotective effect of BMS-induced PC. In summary, BMS depolarizes mitochondria without ROS generation, activates the PI3K—Akt pathway, improves ATP content, and increases catalase expression. These mechanisms appear to play important roles in the neuroprotective effect of BMS.

Neuroprotective effects of vitexin by inhibition of NMDA receptors in primary cultures of mouse cerebral cortical neurons

2013 ◽  
Vol 386 (1-2) ◽  
pp. 251-258 ◽  
Author(s):  
Le Yang ◽  
Zhi-ming Yang ◽  
Nan Zhang ◽  
Zhen Tian ◽  
Shui-bing Liu ◽  
...  
Keyword(s):  
Nmda Receptors ◽  
Cortical Neurons ◽  
Primary Cultures ◽  
Neuroprotective Effects ◽  
Cerebral Cortical Neurons

scholarly journals Astrocytes enhance the tolerance of rat cortical neurons to glutamate excitotoxicity

2018 ◽  
Author(s):  
Li‑Nan Zhang ◽  
Qi Wang ◽  
Xiao‑Hui Xian ◽  
Jie Qi ◽  
Li‑Zhe Liu ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Glutamate Excitotoxicity ◽  
Rat Cortical Neurons

Role of Cannabidiol and Tetrahydrocannabivarin on Paclitaxel-Induced Neuropathic Pain in Rodents

2021 ◽  
Author(s):  
Anil Kumar Kalvala ◽  
Arvind Bagde ◽  
Peggy Arthur ◽  
Sunil Kumar Surapaneni ◽  
Ramesh Nimma ◽  
...  
Keyword(s):  
Primary Cultures ◽  
P38 Map Kinase ◽  
Control Group ◽  
Cb1 Receptors ◽  
Neuroprotective Effects ◽  
Sd Rats ◽  
Protein Expressions ◽  
Behavioral Parameters ◽  
Neurobehavioral Symptoms

Abstract The purpose of this study was to investigate the neuroprotective effects of phytocannabinoids, synthetic cannabidiol (CBD) and tetrahydrocannabivarin (THCV) and their combination on taxol induced peripheral neuropathy (PIPN) in mice. Briefly, six groups of C57BL/6J mice (n = 6) were used. PTX (8 mg/kg/day, i.p.) was given to the mice on days 1, 3, 5, and 7 to induce neuropathy. Mice were evaluated for their behavioral parameters and also at the end of the study, DRG collected from the animals were subjected to RNA sequence and westernblot analysis. Further, immunocytochemistry and mitochondrial functional assays were performed on cultured DRGs derived from SD rats. The combination of CBD and THCV improved thermal and mechanical neurobehavioral symptoms in mice by two folds as compared to individual treatments. KEGG (RNA Sequencing) identified P38-MAPK, AMPK, and PI3K-AKT pathways as potential CBD and THCV therapeutic targets. In PTX-treated animals, the expression of p-AMPK, SIRT1, NRF2, HO1, SOD2, and catalase was significantly reduced (p<0.001), whereas the expression of PI3K, p-AKT, p-P38 MAP kinase, BAX, TGF-, NLRP3 inflammasome, and caspase 3 was significantly increased (p<0.001) when compared to control group. In reversing these protein expressions, combination therapy outperformed single therapies. CBD and THCV treatment increased AMPK, Catalase, and Complex I expression while decreasing mitochondrial superoxides in DRG primary cultures. In mice and DRG primary cultures, WAY100135 and rimonabant inhibited the effects of CBD and THCV by blocking 5 HT1A and CB1 receptors. In conclusion, entourage effect of CBD and THCV combination against PIPN appears to protect neurons in mice by modulating 5HT1A and CB1 receptors, respectively.

scholarly journals Nckβ Adapter Controls Neuritogenesis by Maintaining the Cellular Paxillin Level

2007 ◽  
Vol 27 (17) ◽  
pp. 6001-6011 ◽  
Author(s):  
Shengxi Guan ◽  
Mei Chen ◽  
David Woodley ◽  
Wei Li
Keyword(s):  
Pc12 Cells ◽  
Cortical Neurons ◽  
State Level ◽  
Cell Types ◽  
Steady State Level ◽  
Down Regulation ◽  
Evolutionarily Conserved ◽  
Rat Cortical Neurons ◽  
Interfering Rna

ABSTRACT The SH2/SH3 adapter Nck has an evolutionarily conserved role in neurons, linking the cell surface signals to actin cytoskeleton-mediated responses. The mechanism, however, remains poorly understood. We have investigated the role of Nck/Nckα/Nck1 versus Grb4/Nckβ/Nck2 side-by-side in the process of mammalian neuritogenesis. Here we show that permanent genetic silencing of Nckβ, but not Nckα, completely blocked nerve growth factor-induced neurite outgrowth in PC12 cells and dramatically disrupted the axon and dendrite tree in primary rat cortical neurons. By screening for changes among the components reportedly present in complex with Nck, we found that the steady-state level of paxillin was significantly reduced in Nckβ knockdown, but not Nckα knockdown, neurons. Interestingly, Nckβ knockdown did not affect the paxillin level in glial cells and several other cell types of various tissue origins. Genetic silencing of paxillin blocked neuritogenesis, just like Nckβ knockdown. Reintroducing a nondegradable Nckβ into Nckβ short interfering RNA-expressing PC12 cells rescued paxillin from down-regulation and allowed the resumption of neuritogenesis. Forced expression of paxillin in Nckβ knockdown PC12 also rescued its capacity for neuritogenesis. Finally, Nckβ, but not Nckα, binds strongly to paxillin and treatment of the neurons with proteosome inhibitors prevented paxillin down-regulation in Nckβ knockdown neurons. Thus, Nckβ maintains paxillin stability during neuritogenesis.

A Role of Peroxides in Ca2+Ionophore-Induced Apoptosis in Cultured Rat Cortical Neurons

1996 ◽  
Vol 227 (2) ◽  
pp. 513-518 ◽  
Author(s):  
Yutaka Hatanaka ◽  
Keiichiro Suzuki ◽  
Yoshimi Kawasaki ◽  
Yasuhisa Endo ◽  
Naoyuki Taniguchi ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Rat Cortical Neurons ◽  
Induced Apoptosis

scholarly journals Excitotoxic glutamate causes neuronal insulin resistance by inhibiting insulin receptor/Akt/mTOR pathway

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Igor Pomytkin ◽  
Irina Krasil’nikova ◽  
Zanda Bakaeva ◽  
Alexander Surin ◽  
Vsevolod Pinelis
Keyword(s):  
Insulin Resistance ◽  
Insulin Receptor ◽  
Cortical Neurons ◽  
Glycogen Synthase ◽  
Primary Cultures ◽  
Biological Response ◽  
Mtor Pathway ◽  
Serine Phosphorylation ◽  
Glutamate Excitotoxicity ◽  
Neuronal Insulin Resistance

Abstract Aim An impaired biological response to insulin in the brain, known as central insulin resistance, was identified during stroke and traumatic brain injury, for which glutamate excitotoxicity is a common pathogenic factor. The exact molecular link between excitotoxicity and central insulin resistance remains unclear. To explore this issue, the present study aimed to investigate the effects of glutamate-evoked increases in intracellular free Ca2+ concentrations [Ca2+]i and mitochondrial depolarisations, two key factors associated with excitotoxicity, on the insulin-induced activation of the insulin receptor (IR) and components of the Akt/ mammalian target of rapamycin (mTOR) pathway in primary cultures of rat cortical neurons. Methods Changes in [Ca2+]i and mitochondrial inner membrane potentials (ΔΨm) were monitored in rat cultured cortical neurons, using the fluorescent indicators Fura-FF and Rhodamine 123, respectively. The levels of active, phosphorylated signalling molecules associated with the IR/Akt/mTOR pathway were measured with the multiplex fluorescent immunoassay. Results When significant mitochondrial depolarisations occurred due to glutamate-evoked massive influxes of Ca2+ into the cells, insulin induced 48% less activation of the IR (assessed by IR tyrosine phosphorylation, pY1150/1151), 72% less activation of Akt (assessed by Akt serine phosphorylation, pS473), 44% less activation of mTOR (assessed by mTOR pS2448), and 38% less inhibition of glycogen synthase kinase β (GSK3β) (assessed by GSK3β pS9) compared with respective controls. These results suggested that excitotoxic glutamate inhibits signalling via the IR/Akt/mTOR pathway at multiple levels, including the IR, resulting in the development of acute neuronal insulin resistance within minutes, as an early pathological event associated with excitotoxicity.

Sign in / Sign up

Export Citation Format

Share Document