NG108-15 Cells Research Articles

63 Developing a 3D in Vitro Schwann Cell Model of Myelination for Peripheral Nerve Injury

Abstract Aim This study investigated the effectiveness of fabricating engineered neural tissue (EngNT) to develop a 3D in vitro model of myelination for peripheral nerve injury. Additionally, the effect of metformin and sulindac sulfide in nerve regeneration was evaluated by assessing neurite growth in both monolayer and 3D co-culture systems. Method Neuronal cells (NG108-15 and SH-SY5Y cell lines) were treated with metformin for 72 hrs in an Incucyte® live-cell analysis system. EngNT cellular collagen gels were fabricated using Schwann cells (SCL4.1/F7), SCL4.1/F7:NG108-15 (1:1) cells or harvested rat dorsal root ganglion cells. NG108–15 cells were co-cultured with SCL4.1/F7 cellular gels. 3D EngNT co-cultures were treated with metformin and sulindac sulfide for 72 hrs. EngNT cellular gels were analysed with transmission electron microscopy (TEM). Results TEM evaluation of EngNT co-cultures demonstrated the enfoldment of neurones by Schwann cells resulting in cell-cell contacts and myelination was identified. NG108-15 and SH-SY5Y cells exhibited significant neurite growth with 100 μM metformin being the optimal dose (151.4 ± 3 μM and 108.0 ± 12 μM respectively). Increased neurite growth of NG108-15 neurones was demonstrated with 100 μM (179.3 ± 2 μM) metformin treatment in 3D EngNT. Additionally, significant neurite growth was demonstrated following treatment with 100 μM (203.9 ± 32 μM) sulindac sulfide. Conclusions A 3D EngNT in vitro co-culture model of Schwann cell myelination was developed illustrating the cell-cell interaction between Schwann cells and neurones and the formation of myelin in the peripheral nervous system. Metformin elicits significant positive results on neurite growth in vitro highlighting its therapeutic potential in PNI.

Alpha-Synuclein and GM1 Ganglioside Co-Localize in Neuronal Cytosol Leading to Inverse Interaction-Relevance to Parkinson's Disease.

Research on GM1 ganglioside and its neuroprotective role in Parkinson's disease (PD), particularly in mitigating the aggregation of α-Synuclein (aSyn), is well established across various model organisms. This essential molecule, GM1, is intimately linked to preventing aSyn aggregation, and its deficiency is believed to play a key role in the initiation of PD. In our current study, we attempted to shed light on the cytosolic interactions between GM1 and aSyn based on previous reports demonstrating gangliosides and monomeric aSyn to be present in neuronal cytosol. Native-PAGE and Western blot analysis of neuronal cytosol from mouse brains demonstrated the presence of both GM1 and monomeric aSyn in the neuronal cytosol of normal mouse brain. To demonstrate that an adequate level of GM1 prevents the aggregation of aSyn, we used NG108-15 and SH-SY5Y cells with and without treatment of 1-phenyl-2-palmitoyl-3-morpholino-1-propanol (PPMP), which inhibits the synthesis/expression of GM1. Cells treated with PPMP to reduce GM1 expression showed a significant increase in the formation of aggregated aSyn compared to untreated cells. We thus demonstrated that sufficient GM1 prevents the aggregation of aSyn. For this to occur, aSyn and GM1 must show proximity within the neuron. The present study provides evidence for such co-localization in neuronal cytosol, which also facilitates the inverse interaction revealed in studies with the two cell types above. This adds to the explanation of how GM1 prevents the aggregation of aSyn and onset of Parkinson's disease.

Synthesis of Ethyl Methyl 4-aryl-1,4-dihydropyridine-3,5-dicarboxylates as Potential Calcium Channel Blockers for Hypertension

Aim: Several new dihydropyridine-based calcium channel blockers have been synthesized and pharmacologically evaluated for the treatment of hypertension Background: Dihydropyridines constitute an important class of calcium channel blockers (CCBs) due to their high potency, wide heterogeneity and tremendous biological usefulness. As a follow-up to our previous studies on 4-aryl-1,4-dihydropyridines as calcium channel blockers for the treatment of hypertension, four new series of methyl ethyl ester substituted 1,4-dihydropyridines are reported. Objectives: The aim of the work was to study the effects of unsymmetrical ester substitutions on calcium channel blocking activity of dihydropyridines (DHPs) while retaining the aminoalkoxy side chain at various positions of the 4-aryl ring. The type and location of the substituents on the 4-aryl ring have been extensively explored to study the structure-activity relationship (SAR) in this series of dihydropyridines as calcium channel blockers. Methodology: The target DHPs were synthesized using modified Hantzsch condensation and further derivatization. The compounds were screened for their inhibitory potential against L-type calcium channels at a single concentration of 10 μM on NG108-15 cells (Neuroblastoma X Glioma). The most potent DHP 12 was also tested for its vasodilatory activity using rat thoracic aortic rings precontracted with KCl (30 mM) and in vivo antihypertensive activity in rats using the tail-cuff method. Results: The newly synthesized DHPs displayed diversified calcium channel blocking activity with compounds 1e, 1h, 2d, 2f, 2h, 6, 9, 11, 12 and 14, producing more than 50% inhibition of veratridine response. 3-imidazolylpropoxy substituted analogue 12 turned out to be the most potent compound of the four series of compounds and produced fairly higher inhibition (78.6%) of veratridine response in comparison to nifedipine (70%) at 10 μM. In addition, compound 12 produced potent vasodilatory and antihypertensive properties. Conclusion: Both location of the side chain and the type of substituent on methyl ethyl ester substituted 4-aryl ring affected the response of dihydropyridine derivatives towards L-type calcium channels.

P21-24: THJ-2201, a synthetic cannabinoid, modulates mitochondrial function and dynamics during the neurodifferentiation of NG108-15 cells at biologically relevant concentrations

P21-24: THJ-2201, a synthetic cannabinoid, modulates mitochondrial function and dynamics during the neurodifferentiation of NG108-15 cells at biologically relevant concentrations

P21-12: The Synthetic Sannabinoid ADB-FUBINACA decreases global DNA methylation during the neuronal differentiation of NG108-15 cells by increasing TET activity

P21-12: The Synthetic Sannabinoid ADB-FUBINACA decreases global DNA methylation during the neuronal differentiation of NG108-15 cells by increasing TET activity

Docosahexaenoic acid contributes to increased CaMKII protein expression and a tendency to increase nNOS protein expression in differentiated NG108-15 cells.

Docosahexaenoic acid (DHA; 22:6n-3), an n-3 polyunsaturated fatty acid, has various important roles in brain functions. Nitric oxide (NO) produced by neuronal NO synthase (nNOS) and Ca2+/calmodulindependent protein kinase II (CaMKII) is also involved in brain functions. We investigated the influence of DHA on nNOS and CaMKII protein expression in differentiated NG108-15 cells. NG108-15 cells were seeded in 12-well plates, and after 24 h, the medium was replaced with Dulbecco's modified Eagle's medium containing 1% fetal bovine serum, 0.2 mM dibutyryl cyclic adenosine monophosphate and 100 nM dexamethasone as differentiation-inducing medium. When cells were cultured in differentiation-inducing medium, neurite-like outgrowths were observed on days 5 and 6. However, no significant difference in morphology was observed in cells with or without DHA treatment. With or without DHA addition, nNOS protein expression was increased on days 5 and 6 compared with day 0. This increase tended to be enhanced by DHA. CaMKII protein expression did not change after differentiation without DHA, but was significantly increased on day 6 compared with day 0 with DHA addition. These data indicate that DHA is involved in brain functions by regulating CaMKII and nNOS protein expression.

Dynamic optical clamp: A novel electrophysiology tool and a technique for closed-loop stimulation

Optical methods of neuromodulation show great promise. Recent research has shown that optogenetic and electrical stimulation interact both in vitro and in vivo to facilitate action potentials. With standard electrophysiology approaches, it is not possible to directly compare the cell’s response to a test pulse after an optical or electrical stimulation that lead to the same depolarisation. This paper describes the development of a new “dynamic optical clamp” technique, which aims to build on existing voltage clamp methods, but using light as the clamping input in place of electrical currents. We propose a technique based on combinations of optical and electrical stimulation to clamp membrane potential optically. After illustrating the problem in the context of optogenetically-active spiral ganglion neurons from transgenic mice, the proposed optical clamp was first tested within a NEURON simulation and then demonstrated in vitro with NG108-15 cells transfected with a Channelrhodopsin-2 plasmid. Testing of different control schemes within the NEURON simulation showed that a proportional–integral–derivative controller was appropriate for this application. The dynamic optical clamp technique allowed the membrane voltage of optogenetically-modified NG108-15 cells to be controlled using only light during electrophysiology studies. In order to translate optical approaches into implantable devices, a greater understanding of both the mechanisms of optical modulation and the engineering limitations is desirable. The dynamic optical clamp can be adapted for use in closed-loop neuronal control in future generations of neuroprosthetic devices. The enhanced control afforded by this technique could facilitate future investigations of ion channel dynamics during optical stimulation.

The miR-34b-5p-negative target Gnai2 aggravates fluorine combined with aluminum-induced apoptosis of rat offspring hippocampal neurons and NG108-15 cells.

It is known that fluorine and aluminum are commonly found in the environment and that long-term overexposure can adversely affect the organism's nervous system, damaging the structure and function of brain tissue. Our previous study showed that fluorine combined with aluminum (FA) could trigger apoptosis in vitro and cause spatial learning and memory impairment and differentially expressed miRNAs (including miR-34b-5p) in the hippocampi in vivo. However, the detailed mechanism is unclear. Learning memory damage is implicated in excessive hippocampal neuron apoptosis, and miR-34b-5p participates in regulating the hippocampal neuron apoptosis. Thus, in the current research, Sprague-Dawley (SD) rats were subjected to FA, and NG108-15 control cells and NG108-15 cells pretransfected with miR-34b-5p agomir or antagomir were exposed to FA. We found that FA triggered apoptosis of rat hippocampal neurons and NG108-15 cells, increased miR-34b-5p expression, and decreased Gnai2, PKA, ERK and CREB expression. Inhibition of miR-34b-5p alleviated FA-induced NG108-15 cell apoptosis and further increased Gnai2, PKA, ERK, and CREB expression, and vice versa. Furthermore, miR-34b-5p modulated the level of Gnai2 by directly targeting its 3'-untranslated region (UTR), as verified through the dual Luciferase reporter assay. These outcomes suggested that miR-34b-5p participated in FA-induced neuronal apoptosis by targeting Gnai2 negatively, thereby inhibiting the PKA/ERK/CREB signaling pathway.

Oxoglutarate dehydrogenase complex controls glutamate-mediated neuronal death

Brain injury is accompanied by neuroinflammation, accumulation of extracellular glutamate and mitochondrial dysfunction, all of which cause neuronal death. The aim of this study was to investigate the impact of these mechanisms on neuronal death.Patients from the neurosurgical intensive care unit suffering aneurysmal subarachnoid hemorrhage (SAH) were recruited retrospectively from a respective database. In vitro experiments were performed in rat cortex homogenate, primary dissociated neuronal cultures, B35 and NG108-15 cell lines. We employed methods including high resolution respirometry, electron spin resonance, fluorescent microscopy, kinetic determination of enzymatic activities and immunocytochemistry.We found that elevated levels of extracellular glutamate and nitric oxide (NO) metabolites correlated with poor clinical outcome in patients with SAH. In experiments using neuronal cultures we showed that the 2-oxoglutarate dehydrogenase complex (OGDHC), a key enzyme of the glutamate-dependent segment of the tricarboxylic acid (TCA) cycle, is more susceptible to the inhibition by NO than mitochondrial respiration. Inhibition of OGDHC by NO or by succinyl phosphonate (SP), a highly specific OGDHC inhibitor, caused accumulation of extracellular glutamate and neuronal death. Extracellular nitrite did not substantially contribute to this NO action. Reactivation of OGDHC by its cofactor thiamine (TH) reduced extracellular glutamate levels, Ca2+ influx into neurons and cell death rate. Salutary effect of TH against glutamate toxicity was confirmed in three different cell lines.Our data suggest that the loss of control over extracellular glutamate, as described here, rather than commonly assumed impaired energy metabolism, is the critical pathological manifestation of insufficient OGDHC activity, leading to neuronal death.

Medium chain length polyhydroxyalkanoates as potential matrix materials for peripheral nerve regeneration.

Polyhydroxyalkanoates are natural, biodegradable, thermoplastic and sustainable polymers with a huge potential in fabrication of bioresorbable implantable devices for tissue engineering. We describe a comparative evaluation of three medium chain length polyhydroxyalkanoates (mcl-PHAs), namely poly(3-hydroxyoctanoate), poly(3-hydroxyoctanoate-co-3-hydoxydecanoate) and poly(3-hydroxyoctanoate-co-3-hydroxydecanoate-co-3-hydroxydodecanoate), one short chain length polyhydroxyalkanoate, poly(3-hydroxybutyrate), P(3HB) and synthetic aliphatic polyesters (polycaprolactone and polylactide) with a specific focus on nerve regeneration, due to mechanical properties of mcl-PHAs closely matching nerve tissues. In vitro biological studies with NG108-15 neuronal cell and primary Schwann cells did not show a cytotoxic effect of the materials on both cell types. All mcl-PHAs supported cell adhesion and viability. Among the three mcl-PHAs, P(3HO-co-3HD) exhibited superior properties with regards to numbers of cells adhered and viable cells for both cell types, number of neurite extensions from NG108-15 cells, average length of neurite extensions and Schwann cells. Although, similar characteristics were observed for flat P(3HB) surfaces, high rigidity of this biomaterial, and FDA-approved polymers such as PLLA, limits their applications in peripheral nerve regeneration. Therefore, we have designed, synthesized and evaluated these materials for nerve tissue engineering and regenerative medicine, the interaction of mcl-PHAs with neuronal and Schwann cells, identifying mcl-PHAs as excellent materials to enhance nerve regeneration and potentially their clinical application in peripheral nerve repair.

Organophosphate agent action at the fatty acid amide hydrolase enhancing anandamide-induced apoptosis in NG108-15 cells.

Organophosphate (OP) agents are continuously utilized in large amount throughout the globe for crop protection and public health, thereby creating a potential concern on human health. OP agent as an anticholinesterase also acts on the endocannabinoid (EC)-hydrolases, i.e., fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), to reveal unexpected adverse effects including ADHD-like behaviors in adolescent male rats. The present investigation examines a hypothesis that OP compound inhibiting the EC-hydrolase(s) dysregulates the EC-signaling system, triggering apoptosis in neuronal cells. Ethyl octylphosphonofluoridate (EOPF), as an OP probe, preferably acts on FAAH over MAGL in intact NG108-15 cells. Anandamide (AEA), an endogenous FAAH substrate, is cytotoxic in a concentration-dependent manner, although 2-arachidonoylglycerol, an endogenous MAGL substrate, gives no effect in the concentrations examined here. EOPF pretreatment markedly enhances AEA-induced cytotoxicity. Interestingly, the cannabinoid receptor blocker AM251 diminishes AEA-induced cell death, whereas AM251 does not prevent the cell death in the presence of EOPF. The consistent results are displayed in apoptosis markers evaluation (caspases and mitochondrial membrane potential). Accordingly, FAAH inhibition by EOPF suppresses AEA-metabolism, and accumulated excess AEA overstimulates both the cannabinoid receptor- and mitochondria-mediated apoptotic pathways.

6-Gingerol, a major ingredient of ginger, attenuated cisplatin-induced pica in rats via regulating 5-HT3R/Ca2+/CaMKII/ERK1/2 signaling pathway

6-gingerol, the representative single ingredient in ginger, was demonstrated antiemetic properties against CINV via blocking the 5-hydroxytryptamine 3 receptors (5-HT3Rs), however, its underlying mechanism has not been fully clarified. Emerging evidence suggested that the 5-HT3R-mediated activation of calcium/calmodulin-dependent protein kinase II/extracellular signal-regulated kinase 1/2 (Ca2+/CaMKII/ERK1/2) signaling pathway may contribute to the occurrence of CINV. We first verified the antiemetic action of 6-gingerol via a cisplatin-induced pica model of rats, and found that 6-gingerol significantly reduced the kaolin intake. Further, 6-gingerol markedly down-regulated the expression of 5-HT3Rs and the levels of calmodulin, CaMKII, p-CaMKII, ERK1/2, p-ERK1/2, and β-arrestin2. Additionally, we demonstrated that 6-gingerol significantly decreased the level of intracellular Ca2+ in NG108-15 cells, and inhibited the Ca2+/CaMKII/ERK1/2 signaling pathway mediated by 5-HT3Rs. Taken together, 6-gingerol has an antiemetic effect against CINV, and the underlying mechanism may be related to the inhibition of the 5-HT3R-mediated Ca2+/CaMKII/ERK1/2 signaling pathway.

Role and Mechanism of MicroRNA-7a-5p in Paraventricular Nucleus on Sympathetic Overactivity in the Spontaneously Hypertensive Rats

Abstract Background To investigate the role and mechanism of microRNA-7a-5p (miR-7a-5p) in paraventricular nucleus on sympathetic overactivity in the spontaneously hypertensive rats (SHR). Methods Wistar-Kyoto (WKY) rats and SHR aged 12 weeks were randomly divided into recombinant adeno-associated virus (rAAV) overexpressing miR-7a-5p mimic, miR-7a-5p negative control (NC), antimiR-7a-5p, or NC of antimir-7a-5p treatment groups (n = 6 per group). In addition, WKY rats and SHR aged 12 weeks were randomly divided into rAAV overexpressing GABRA1, GABRA1 NC, GABRA1 shRNA, or NC of GABRA1 shRNA treatment groups (n = 6 per group). Four weeks later, hemodynamic parameters, renal sympathetic nerve activity (RSNA), and plasma norepinephrine levels were observed. Results Four weeks after injection of rAAV into the paraventricular nucleus, overexpression of miR-7a-5p mimic increased RSNA and mean arterial pressure (MAP) in WKY and SHR (all P < 0.05). The number of FosB positive neurons in paraventricular nucleus was significantly upregulated (all P < 0.01) while the number of GABRA1 positive neurons in paraventricular nucleus was significantly downregulated (all P < 0.01). Overexpression of GABRA1 in hypothalamic paraventricular nucleus decreased RSNA and MAP in WKY and SHR (all P < 0.05). Compared with WKY, the overexpression or knockdown of miR-7a-5p/GABRA1 had more significant effect on RSNA and MAP in SHR (all P < 0.05). The expression of miR-7a-5p in hypothalamic paraventricular nucleus in SHR was significantly upregulated (P < 0.01) while GABRA1 protein levels were significantly downregulated (P < 0.01). miR-7a-5p mimic transfection in primary brain neurons or NG108 cells resulted in significant downregulation of GABRA1 protein expression. TargetScan prediction showed that there was sequence binding at the 3′UTR end of GABRA1 mRNA by miR-7a-5p. Dual luciferase reporter assay confirmed that miR-7a-5p can target GABRA1 gene. Conclusions miR-7a-5p in hypothalamic paraventricular nucleus increases RSNA by inhibiting GABRA1 expression, and may contribute to the development of hypertension.

Apoptosis of NG108-15 cells induced by fluorine combined with aluminum exposure and the effect of curcumin intervention

The mechanism by which the combination of fluorine and aluminum (FA) cause learning and memory impairment is still unclear. Curcumin is a yellow polyphenol extracted from the rhizome of the plant curcuma longa linn, which has anti-apoptotic and antioxidant functions; studies have shown that the PKC-NMDAR pathway plays an important role in the process of cell apoptosis. Based on the above, we designed an in vitro study on the role of curcumin in cell apoptosis caused by coexistence of FA. In this study, the cell viability of NG108-15 cell was detected by CCK-8; cell apoptosis was detected by AO/EB dual fluorescence staining kit; mRNA expressions of PKC and NMDAR were evaluated by qRT-PCR and protein expressions of caspase3, Bax, Bcl-2, PKC and NMDAR were evaluated by WB. Our results showed that curcumin alleviated FA-induced apoptosis of NG108-15 cells, possibly by inhibiting the increase of caspase3 protein and Bax protein, and the decrease of Bcl-2 protein, thereby upregulating the expression of PKC and NMDAR to exert neuroprotective effect.

Docosahexaenoic Acid Increases Vesicular Glutamate Transporter 2 Protein Levels in Differentiated NG108-15 Cells.

Docosahexaenoic acid (DHA; 22:6n-3), which is enriched in the neuronal membrane, plays a variety of roles in the brain. Vesicular glutamate transporters (VGLUTs) are responsible for incorporating glutamine into synaptic vesicles. We investigated the influence of DHA on the fatty acid profile and the levels of VGLUT1 and VGLUT2 proteins in differentiated NG108-15 cells, a neuroblastoma-glioma hybrid cell line. NG108-15 cells were plated and 24 h later the medium was replaced with Dulbecco's modified Eagle's medium supplemented with 1% fetal bovine serum, 0.2 mM dibutyryl cAMP, and 100 nM dexamethasone, which was added to induce differentiation. After 6 d, the amount of DHA in the cells was increased by addition of DHA to the medium. VGLUT2 levels were increased by the addition of DHA. These data indicate that DHA affected the levels of VGLUT2 in NG108-15 cells under differentiation-promoting conditions, suggesting that DHA affects brain functions involving VGLUT2.

P16-10 The synthetic cannabinoid ADB-FUBINACA modulates mitochondrial activity and dynamics during neurodifferentiation of NG108-15 cells

P16-10 The synthetic cannabinoid ADB-FUBINACA modulates mitochondrial activity and dynamics during neurodifferentiation of NG108-15 cells

Golgi stress induces upregulation of the ER-Golgi SNARE Syntaxin-5, altered βAPP processing, and Caspase-3-dependent apoptosis in NG108-15 cells

The involvement of secretory pathways and Golgi dysfunction in neuronal cells during Alzheimer's disease progression is poorly understood. Our previous overexpression and knockdown studies revealed that the intracellular protein level of Syntaxin-5, an endoplasmic reticulum-Golgi soluble N-ethylmaleimide-sensitive factor-attachment protein receptor (SNARE), modulates beta-amyloid precursor protein processing in neuronal cells. We recently showed that changes in endogenous Syntaxin-5 protein expression occur under stress induction. Syntaxin-5 was upregulated by endoplasmic reticulum stress but was degraded by Caspase-3 during apoptosis in neuronal cells. In addition, we showed that sustained endoplasmic reticulum stress promotes Caspase-3-dependent apoptosis during the later phase of the endoplasmic reticulum stress response in NG108-15 cells. In this study, to elucidate the consequences of secretory pathway dysfunction in beta-amyloid precursor protein processing that lead to neuronal cell death, we examined the effect of various stresses on endoplasmic reticulum-Golgi SNARE expression and beta-amyloid precursor protein processing. By using compounds to disrupt Golgi function, we show that Golgi stress promotes upregulation of the endoplasmic reticulum-Golgi SNARE Syntaxin-5, and prolonged stress causes Caspase-3-dependent apoptosis. Golgi stress induced intracellular beta-amyloid precursor protein accumulation and a concomitant decrease in total amyloid-beta production. We also examined the protective effect of the chemical chaperone 4-phenylbutylate on changes in amyloid-beta production and the activation of Caspase-3 induced by endoplasmic reticulum and Golgi stress. The compound alleviated the increase in the amyloid-beta 1–42/amyloid-beta 1–40 ratio induced by endoplasmic reticulum and Golgi stress. Furthermore, 4-phenylbutylate could rescue Caspase-3-dependent apoptosis induced by prolonged organelle stress. These results suggest that organelle stress originating from the endoplasmic reticulum and Golgi has a substantial impact on the amyloidogenic processing of beta-amyloid precursor protein and Caspase-3-dependent apoptosis, leading to neuronal cell death.

Mitochondrial effects and Caspase-3 activation induced by synthetic cannabinoids in NG108-15 cells

Mitochondrial effects and Caspase-3 activation induced by synthetic cannabinoids in NG108-15 cells

AMB-Fubinaca, AB-Chminaca and HU-308’s effects on in vitro differentiation and proliferation of NG108-15 cells

AMB-Fubinaca, AB-Chminaca and HU-308’s effects on in vitro differentiation and proliferation of NG108-15 cells

Synthetic cannabinoids affect the expression of autophagic mediators ATG5, BECLIN-1, RAB7A and LC3 in brain-derived NG108-15 cells

Synthetic cannabinoids affect the expression of autophagic mediators ATG5, BECLIN-1, RAB7A and LC3 in brain-derived NG108-15 cells