Neuronal Cell Proliferation Research Articles

A Compound Heterozygous Pathogenic Variant in B4GALNT1 Is Associated With Axonal Charcot-Marie-Tooth Disease.

Background and PurposePathogenic variants in B4GALNT1 have been reported to cause hereditary spastic paraplegia 26. This study has revealed that a novel compound heterozygous pathogenic variant in B4GALNT1 is associated with axonal Charcot-Marie-Tooth disease (CMT).MethodsWhole-exome sequencing (WES) was used to identify the causative factors and characterize the clinical features of a Korean family with sensorimotor polyneuropathy. Functional assessment of the mutant genes was performed using a motor neuron cell line.ResultsThe WES revealed a compound heterozygous pathogenic variant (c.128dupC and c.451G>A) in B4GALNT1 as the causative of the present patient, a 53-year-old male who presented with axonal sensorimotor polyneuropathy and cognitive impairment without spasticity. The electrodiagnostic study showed axonal sensorimotor polyneuropathy. B4GALNT1 was critical to the proliferation of motor neuron cells. The compensation assay revealed that the pathogenic variants might affect the enzymatic activity of B4GALNT1.ConclusionsThis study is the first to identify a case of autosomal recessive axonal CMT associated with a compound heterozygous pathogenic variant in B4GALNT1. This finding expands the clinical and genetic spectra of peripheral neuropathy.

Magnetic Resonance Spectroscopy in Evaluation of Focal Brain Lesions- A Cross-sectional Prospective Study

Introduction: The characterisation of intracranial mass lesions only with the help of conventional magnetic resonance imaging alone may be inconclusive. Magnetic Resonance Spectroscopy (MRS) is a non invasive technique which is superior to Magnetic Resonance Imaging (MRI) in the characterisation of brain lesions. Magnetic resonance spectroscopy is comparatively fast, non-invasive method that gives biochemical analysis of the normal brain parenchyma and of the pathological processes. Magnetic resonance spectroscopy has the advantage of providing characterisation of tissues based on their molecular composition. It gives information about neuronal vitality, cell proliferation, degradation and energy metabolism. Aim: To describe the spectrum of magnetic resonance spectroscopy in focal brain lesions and to detect the metabolic and biochemical changes in various focal brain lesions. Also, to distinguish neoplastic from non-neoplastic lesions. Materials and Methods: This prospective study was carried out at Department of Radiodiagnosis, Sri Manakula Vinaynagar Medical College and Hospital, Puducherry, India for a period of 18 months from November 2017 to April 2019. A total of 40 MRI brain with clinically suspected brain lesions were included in the study. Magnetic resonance spectroscopy studies were performed in all patients with focal brain lesions. On the basis of spectral and distribution patterns of the pathologic spectra seen in MR spectroscopy, a qualitative analysis was done. The metabolic area ratios Choline/Creatinine (Cho/Cr)/Cr, NAA/Cho and NAA/Cr were evaluated (NAA- N-acetyl, Cho- choline, Cr- creatine). Data was collected using prescribed proforma and analysed using Statistical Package for the Social Sciences (SPSS) 22 version software. Results: Out of the 40 patients evaluated 11 cases were high grade gliomas, seven cases were Neurocysticercosis, five low grade glioma, five meningioma, four metastasis, four tubercular abscesses, two tuberculoma and two lymphoma. Increased Cho/ Cr ratio was noted in neoplastic lesions when compared to non neoplastic lesions. Conclusion: The MRS in addition to appropriate conventional MRI sequences provides useful supplementary information and has a potential to validate treatment strategies. Neoplastic lesions show elevated choline and Cho Cr ratio with reduction in N-acetyl aspartate (NAA), whereas non neoplastic lesions show decreased Cho/Cr ratio. Hence, MRS could be a problem solving tool in differentiating neoplastic from non neoplastic lesions.

Ketamine and Propofol Protect Neuron Cells from Oxygen-Glucose Deprivation-Induced Injury through SAPK/JNK Signalling Pathway.

Ketamine and propofol are commonly used anaesthetic reagents. Recent research revealed that ketamine and propofol have an important role in cell survival. However, it remains unknown whether they affect the outcome of hypoxic-ischemic brain injury. To address this issue, we in this study investigated the effects of ketamine and propofol on the survival and proliferation of neuronal PC12 cells after exposure to oxygen-glucose deprivation- (OGD-) induced injury. PC12 cells were maintained under a 3-dimensional (3D) culture system to mimic a real physiological microenvironment. The cell injury was induced by 5% CO2 and 95% N2 for a different time point. MTT assay was used for the cell proliferation assay. The cell apoptosis was evaluated by annexin V and propidium iodide (PI) labeling, immunofluorescence staining, transmission electron microscopy (TEM), flow cytometry, and Western blot, respectively. Our results showed that PC12 cell apoptosis was significantly increased for up to 70% after the cells were treated with OGD for 24 hours and reduced to baseline at the 72-hour time point. However, pretreatment with ketamine and propofol significantly protected the cells from OGD-induced cell apoptosis, as evidenced by more expression of antiapoptotic Bcl-2 and lower expression of proapoptotic cleaved caspase-3, phosphor-SAPK/JNK, and phosphor-c-Jun than those of untreated control cells. Thus, we conclude that ketamine and propofol protected PC12 cells from OGD-induced cell apoptosis, at least partially through the SAPK/JNK signalling pathway.

The biophysical basis of receptor tyrosine kinase ligand functional selectivity: Trk-B case study.

Tropomyosin receptor kinase B (Trk-B) belongs to the second largest family of membrane receptors, Receptor Tyrosine Kinases (RTKs). Trk-B is known to interact with three different neurotrophins: Brain-Derived Neurotrophic Factor (BDNF), Neurotrophin-4 (NT-4), and Neurotrophin-3 (NT-3). All three neurotrophins are involved in survival and proliferation of neuronal cells, but each induces distinct signaling through Trk-B. We hypothesize that the different biological effects correlate with differences in the interactions between the Trk-B receptors, when bound to different ligands, in the plasma membrane. To test this hypothesis, we use quantitative FRET to characterize Trk-B dimerization in response to NT-3 and NT-4 in live cells, and compare it to the previously published data for Trk-B in the absence and presence of BDNF. Our study reveals that the distinct Trk-B signaling outcomes are underpinned by both different configurations and different stabilities of the three ligand-bound Trk-B dimers in the plasma membrane.

In‐vitro neuronal cell proliferation and in‐vivo neuroprotective activity of pinus roxburghii for memory and cognition

AbstractBackgroundPinus roxburghii Sarg. is traditionally used as a nerve tonic, hemostatic and anticonvulsant. The present study was aimed to investigate the neuroprotective activity of P. roxburghii stem bark for memory and cognition using in‐vitro and in‐vivo methods.MethodPlant drug was extracted with methanol using Soxhlet extraction. In‐vitro cell viability activity of P. roxburghii was assessed using PC‐12 cell lines. The in‐vivo neuroprotective activity of P. roxburghii was tested on Wistar albino rats (either sex) and ICV‐STZ (3 mg/kg, bilateral) was given to cause memory deficit. HPTLC fingerprinting was performed for the presence of quercetin and gallic acid in the plant extract.ResultThe phytochemical testing of extract revealed the presence of flavonoids, alkaloids, steroids, and tannins. P. roxburghii showed significant cell viability at 10, 50 and 100 µg/ml in an in‐vitro test on PC‐12 cell lines. In the in‐vivo activity, ICV‐STZ caused significant deterioration in memory and cognition, tissue oxidative stress and AchE activity. P. roxburghii 100, 200 and 300 mg/kg, p.o. and donepezil (3 mg/kg, p.o.) significantly (p<0.05) reversed the behavioral changes in rats when tested on morris water maze and elevated plus maze. Increased levels of lipid peroxidation, AchE activity and decreased the level of glutathione were significantly (p<0.05) antagonized by P. roxburghii, similar to donepezil in rat brain. Quercetin and gallic acid were identified quantitatively in the plant extract in HPTLC study.ConclusionThe methanolic extract of P. roxburghii ameliorated ICV‐STZ induced cognitive deficits and memory impairment possibly due to the presence of quercetin and gallic acid.

Understanding Abnormal SMO-SHH Signaling in Autism Spectrum Disorder: Potential Drug Target and Therapeutic Goals.

Autism is a multifactorial neurodevelopmental condition; it demonstrates some main characteristics, such as impaired social relationships and increased repetitive behavior. The initiation of autism spectrum disorder is mostly triggered during brain development by the deregulation of signaling pathways. Sonic hedgehog (SHH) signaling is one such mechanism that influences neurogenesis and neural processes during the development of the central nervous system. SMO-SHH signaling is also an important part of a broad variety of neurological processes, including neuronal cell differentiation, proliferation, and survival. Dysregulation of SMO-SHH signaling leads to many physiological changes that lead to neurological disorders such as ASD and contribute to cognitive decline. The aberrant downregulation of SMO-SHH signals contributes to the proteolytic cleavage of GLI (glioma-associated homolog) into GLI3 (repressor), which increases oxidative stress, neuronal excitotoxicity, neuroinflammation, and apoptosis by suppressing target gene expression. We outlined in this review that SMO-SHH deregulation plays a crucial role in the pathogenesis of autism and addresses the current status of SMO-SHH pathway modulators. Additionally, a greater understanding of the SHH signaling pathway is an effort to improve successful treatment for autism and other neurological disorders.

Modulation of Neuronal Cell Affinity on PEDOT-PSS Nonwoven Silk Scaffolds for Neural Tissue Engineering.

Peripheral nerve injury is a common consequence of trauma with low regenerative potential. Electroconductive scaffolds can provide appropriate cell growth microenvironments and synergistic cell guidance cues for nerve tissue engineering. In the present study, electrically conductive scaffolds were prepared by conjugating poly (3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT-PSS) or dimethyl sulfoxide (DMSO)-treated PEDOT-PSS on electrospun silk scaffolds. Conductance could be tuned by the coating concentration and was further boosted by DMSO treatment. Analogue NG108-15 neuronal cells were cultured on the scaffolds to evaluate neuronal cell growth, proliferation, and differentiation. Cellular viability was maintained on all scaffold groups while showing comparatively better metabolic activity and proliferation than neat silk. DMSO-treated PEDOT-PSS functionalized scaffolds partially outperformed their PEDOT-PSS counterparts. Differentiation assessments suggested that these PEDOT-PSS assembled silk scaffolds could support neurite sprouting, indicating that they show promise to be used as a future platform to restore electrochemical coupling at the site of injury and preserve normal nerve function.

Neuroprotective effects of aromatic turmerone on activity deprivation-induced apoptosis in cerebellar granule neurons.

Ar-turmerone, which is a major bioactive component found in the essential oil derived from Curcuma longa, has been reported to inhibit proliferation and induce apoptosis in cancer cell lines. Recently, ar-turmerone has been reported to increase the proliferation of neuronal stem cells, in contrast to its actions in cancer cells. These observations raise the possibility that ar-turmerone serves specific functions in neuronal cell lineages. However, the effects of ar-turmerone on postmitotic neurons remain elusive. In the present study, we investigated the neuroprotective functions of ar-turmerone in primary cerebellar granule neuronal cultures. We found that ar-turmerone increased the survival of neurons following activity deprivation. Consistently, the induction of cleaved caspase-3, a hallmark of apoptosis, was prevented by ar-turmerone, although neither the level of reactive oxygen species nor the mitochondrial membrane potential was affected. This study reports a neuroprotective function for ar-turmerone, providing new insights into the potential therapeutic applications of ar-turmerone for neurological disorders.

Influence of bacterial components on the developmental programming of enteric neurons.

BackgroundIntestinal bacteria have been increasingly shown to be involved in early postnatal development. Previous work has shown that intestinal bacteria are necessary for the structural development and intrinsic function of the enteric nervous system in early postnatal life. Furthermore, colonization with a limited number of bacteria appears to be sufficient for the formation of a normal enteric nervous system. We tested the hypothesis that common bacterial components could influence the programming of developing enteric neurons.MethodsThe developmental programming of enteric neurons was studied by isolating enteric neural crest‐derived cells from the fetal gut of C57Bl/6 mice at embryonic day 15.5. After the establishment of the cell line, cultured enteric neuronal precursors were exposed to increasing concentrations of a panel of bacterial components including lipopolysaccharide, flagellin, and components of peptidoglycan.Key ResultExposure to bacterial components consistently affected proportions of enteric neuronal precursors that developed into nitrergic neurons. Furthermore, flagellin and D‐gamma‐Glu‐mDAP were found to promote the development of serotonergic neurons. Proportions of dopaminergic neurons remained unchanged. Proliferation of neuronal precursor cells was significantly increased upon exposure to lipopolysaccharide and flagellin, while no significant changes were observed in the proportion of apoptotic neuronal precursors compared to baseline with exposure to any bacterial component.Conclusions and InterfacesThese findings suggest that bacterial components may influence the development of enteric neurons.

Inflammatory lncRNA AK039862 regulates paraquat-inhibited proliferation and migration of microglial and neuronal cells through the Pafah1b1/Foxa1 pathway in co-culture environments

Emerging evidences having suggested that particular lncRNAs have a potential effect on PD progression through provoking damage and inflammatory responses of microglia/ dopaminergic cells. In addition, paraquat can be accumulated in human body through various approaches and have an increased risk for Parkinson’s disease. However, the specific role and mechanism of lncRNA related to neurotoxic in the progression of PD is unclear. In our study, a mouse PD model was established induced by the intraperitoneal injection of paraquat (5 mg/kg and 10 mg/kg) every three days (10 times). We determined differential expression of lncRNA AK039862 and its potential targeted genes Pafah1b1/Foxa1 in PD mouse model, then we used fluorescence in situ hybridization (FISH) to visualize the cellular distribution of AK039862. Short interfering RNAs (siRNAs) and overexpression plasmids were designed for knockdown or overexpression of AK039862. To simulate the coexisting dopaminergic cells and microglia cells in vitro, we applied several non-contact co-culture models, including conditioned medium and Transwell co-culture systems. Cytotoxicity of PQ was evaluated using bv2 cells with the concentrations: 30, 60 μM, and mn9d cells with the concentrations: 50, 100 μM. As a result, we depicted multiple interesting individual and interactive features of inflammatory lncRNA AK039862 involved in PQ-induced cellular functional effects. First, we detected that AK039862 contributed to the neuronal injury process in PQ-treated mice and co-localization of AK039862 with dopaminergic cells in vivo. And interestingly, we demonstrated that PQ significantly inhibited microglia and dopaminergic cells proliferation and microglia migration in vitro. Further research indicated that the PQ-induced low expression of AK039862 rescued microglia proliferation and migration inhibition via the AK039862/Pafah1b1/Foxa1 pathway. Meanwhile, AK039862 also participated in the interaction between microglia and dopaminergic cells with PQ treatment in non-contact co-culture models. In summary, we found that PQ inhibited the proliferation and migration of microglial cells, and elucidated AK039862 played a key role in PQ-induced neuroinflammatory damage through Pafah1b1/Foxa1. Finally, inflammatory AK039862 is involved in the complex communication between microglia and dopaminergic cells in the environment of PQ damage.

Fingerprint-based 2D-QSAR Models for Predicting Bcl-2 Inhibitors Affinity

Background: Bcl-2 family plays an essential role in the cell cycle events incorporating survival, proliferation, and differentiation in normal and neoplastic neuronal cells. Thus, it has been validated as a principal target for the treatment of cancer. For this reason, we will build a model based on a large number of Bcl-2 inhibitors to predict the activities of new compounds as future Bcl-2 inhibitors. Methods: In this study, QSAR models were successfully used to predict the inhibitory activity against Bcl-2 for a set of compounds collected from BDB (Binding database). The kPLS (kernelbased Partial Least-Square) method implemented in Schrodinger's Canvas, was used for searching the correlation between pIC50 and binary fingerprints for a set of known Bcl-2 inhibitors. Results and Discussion: Models based on binary fingerprints with two kPLS factors have been found with decent predictive power (q2 > 0.58), while the optimal number of factors is about 5. The enrichment study (148 actives, 5700 decoys) has shown excellent classification ability of our models (AUC > 0.90) for all cases). Conclusion: We found that the kPLS method, in combination with binary fingerprints, is useful for the affinity prediction and the Bcl-2 inhibitors classification. The obtained promising results, methods, and applications highlighted in this study will help us to design more selective Bcl-2 inhibitors with better structural characteristics and improved anti-cancer activity.

4D printing of stretchable nanocookie@conduit material hosting biocues and magnetoelectric stimulation for neurite sprouting

A high-frequency magnetic field (MF) generates an electric current by charging conductors that enable the induction of various biological processes, including changes in cell fate and programming. In this study, we show that electromagnetized carbon porous nanocookies (NCs) under MF treatment facilitate magnetoelectric conversion for growth factor release and cell stimulation to induce neuron cell differentiation and proliferation in vitro and in vivo. Integrating four-dimensional printing technology, the NCs are exposed on the surface, which enhances the cell adhesion and allows direct manipulation of electromagnetic stimulation of the cells. Remarkably, large amounts of growth factor encapsulated in NC@conduit resulted in excellent permeability and on-demand release, improving the in vivo layers of myelin sheaths and directing the axon orientation at 1 month postimplantation. This study offers proof of principle for MF-guided in vivo neuron regeneration as a potentially viable tissue regeneration approach for neuronal diseases.

IQGAP3 interacts with Rad17 to recruit the Mre11-Rad50-Nbs1 complex and contributes to radioresistance in lung cancer.

IQ motif containing GTPase-activating protein 3 (IQGAP3) has been implicated in diverse cellular processes, including neuronal morphogenesis, cell proliferation and motility, and epithelial-mesenchymal transition. However, its role in cancer radioresistance is completely unknown. Here, we report that IQGAP3 is overproduced in lung cancer patients and correlates with poor clinical outcomes. Functionally, we demonstrate that depletion of IQGAP3 impairs oncogenesis and overcomes radioresistance in lung cancer in vitro and in vivo. Mechanistically, we uncover that IQGAP3 interacts with Rad17 and controls its expression to activate the ATM/Chk2 and ATR/Chk1 signaling pathways by recruiting the Mre11-Rad50-Nbs1 (MRN) complex in response to DNA damage. Moreover, Rad17 is identified as the major downstream effector that mediates the functions of IQGAP3 in lung cancer. Clinically, IQGAP3 overexpression positively correlates with Rad17 upregulation in human lung cancer tissues. Collectively, these data support key role for IQGAP3 in promoting lung cancer radioresistance by interacting with Rad17 and suggest that targeting IQGAP3 may be an attractive strategy for lung cancer radiotherapy.

DNA CpG methylation in sequential glioblastoma specimens

PurposeGlioblastoma is the most aggressive form of brain tumors. A better understanding of the molecular mechanisms leading to its evolution is essential for the development of treatments more effective than the available modalities. Here, we aim to identify molecular drivers of glioblastoma development and recurrence by analyzing DNA CpG methylation patterns in sequential samples.MethodsDNA was isolated from 22 pairs of primary and recurrent formalin-fixed, paraffin-embedded glioblastoma specimens, and subjected to reduced representation bisulfite sequencing. Bioinformatic analyses were conducted to identify differentially methylated sites and pathways, and biostatistics was used to test correlations among clinical and pathological parameters.ResultsDifferentially methylated pathways likely involved in primary tumor development included those of neuronal differentiation, myelination, metabolic processes, synapse organization and endothelial cell proliferation, while pathways differentially active during glioblastoma recurrence involved those associated with cell processes and differentiation, immune response, Wnt regulation and catecholamine secretion and transport.ConclusionDNA CpG methylation analyses in sequential clinical specimens revealed hypomethylation in certain pathways such as neuronal tissue development and angiogenesis likely involved in early tumor development and growth, while suggested altered regulation in catecholamine secretion and transport, Wnt expression and immune response contributing to glioblastoma recurrence. These pathways merit further investigations and may represent novel therapeutic targets.

Endocannabinoid Receptors in the CNS: Potential Drug Targets for the Prevention and Treatment of Neurologic and Psychiatric Disorders.

The endocannabinoid system participates in the regulation of CNS homeostasis and functions, including neurotransmission, cell signaling, inflammation and oxidative stress, as well as neuronal and glial cell proliferation, differentiation, migration and survival. Endocannabinoids are produced by multiple cell types within the CNS and their main receptors, CB1 and CB2, are expressed in both neurons and glia. Signaling through these receptors is implicated in the modulation of neuronal and glial alterations in neuroinflammatory, neurodegenerative and psychiatric conditions, including Alzheimer’s, Parkinson’s and Huntington’s disease, multiple sclerosis, amyotrophic lateral sclerosis, stroke, epilepsy, anxiety and depression. The therapeutic potential of endocannabinoid receptors in neurological disease has been hindered by unwelcome side effects of current drugs used to target them; however, due to their extensive expression within the CNS and their involvement in physiological and pathological process in nervous tissue, they are attractive targets for drug development. The present review highlights the potential applications of the endocannabinoid system for the prevention and treatment of neurologic and psychiatric disorders.

Regulating Age-Related Hearing Loss with Bisphenol A via the Long Non-Coding RNA X Inactive Specific Transcript and MicroRNA-34a-5p Pathways

Age-related hearing loss (AHL) is a common, high-incidence, perceptual disease in the elderly population worldwide. Since bisphenol A (BPA) has been reported to associate with cell apoptosis, we hypothesize that BPA can inhibit the neuronal apoptosis in AHL. Forty Wistar rats were recruited to model AHL; they were then treated with different doses of BPA. We used auditory brainstem response testing to measure the BPA-induced improvement in the rats’ hearing. We examined the proliferation and apoptosis of the auditory cortical neurons in the rats with MTT assay and flow cytometry. Also, to delineate the underlying mechanism of BPA’s effect on AHL, we quantitated the expression level of long non-coding RNA X inactive specific transcript (lncRNA XIST) and miR-34a-5p in the rats’ auditory cortex with a novel method called nanoparticle PCR. We found that BPA intervention improved the hearing of AHL model rats, enhanced neuronal cell proliferation, restricted neuronal cell apoptosis, upregulated miR-34a-5p levels, and downregulated lncRNA XIST levels. The dual-luciferase reporter (DLR) assay revealed that BPA inhibited the apoptosis of auditory cortex neurons by targeting miR-34a-5p with lncRNA XIST and regulated the process of AHL. Therefore, we come to a conclusion that BPA contributes to the improvement of AHL, which may be achieved by upregulating miR-34a-5p and inhibiting the apoptosis of auditory cortex neurons via lncRNA XIST.

The effect of surface modification of poly-lactide-co-glycolide/carbon nanotube nanofibrous scaffolds by laminin protein on nerve tissue engineering.

The presence of biological cues to promote the attachment, proliferation, and differentiation of neuronal cells is important in the process of nerve regeneration. In this study, laminin as a neurite promoting protein, has been used to modify poly-lactide-co-glycolide/carbon nanotube (PLGA/CNT) electrospun nanofibrous scaffolds by means of either mussel-inspired poly(dopamine) (PD) coating or via direct physical adsorption as a simple route for the functionalization of biomaterials. The laminin-modified scaffolds were characterized by a combination of field emission scanning electron microscopy (SEM), X-ray photoelectron spectroscopy, and contact angle measurements. Subsequently, various properties of scaffolds such as degradation time, amount of attached laminin and the rate of CNT release were investigated. The synergistic effect of topographical and biological cues for PC12 cell attachment, proliferation, and differentiation were then studied by SEM and confocal microscopy. The results of degradation study showed that laminin-modified scaffolds were biodegradable with good structural integrity that persisted about 4 weeks. The amount of laminin attached to the PLGA/CNT and PLGA/CNT-PD scaffolds was 3.12 ± 0.6 and 3.04 ± 071 μg per mg of the scaffold, respectively. Although laminin-modified scaffolds could improve cell proliferation identically, neurite extensions on the PLGA/CNT scaffold modified via PD coating (PLGA/CNT-PD-lam scaffold) were significantly longer than those observed on PLGA/CNT scaffold modified via physical adsorption (PLGA/CNT-lam scaffold) and unmodified scaffolds. Together, these results indicated that surface modification via PD coating could be a promising strategy to fabricate biomimetic scaffolds capable of sustaining longer neuronal growth for nerve tissue engineering.

Expression and Functional Study of Single Mutations of Carbonic Anhydrase 8 in Neuronal Cells.

Carbonic anhydrase 8 (CA8), an isozyme of α-carbonic anhydrases, lacks the ability to catalyze the reversible hydration of CO2 to bicarbonate and proton. Previous studies have shown that single point mutations of CA8, CA8-S100P, and CA8-G162R, are associated with novel syndromes including congenital ataxia and mild cognitive impairment. Our previous results demonstrated that overexpression of wild type (WT) CA8 promoted cell proliferation, neurite outgrowth, anti-apoptosis, invasion and migration abilities in neuronal cells. In this study, we examined the expressions and functions of CA8-S100P and CA8-G162R in neuroblastoma cells lines, compared with those of WT CA8. Our results show that the protein expressions of mutant CA8-S100P and CA8-G162R were significantly decreased in Neuro-2a and SK-N-SH cells. Interestingly, CA8-S100P demonstrated a significant increase in cell proliferation in both Neuro-2a and SK-N-SH cells. However, both CA8 mutations showed significantly decreased effects on cell protection and migration in SK-N-SH cells. Surprisingly, a significant increase of invasive ability was observed in SK-N-SH cells with overexpression of CA8-S100P as compared with those with overexpression of WT CA8 under retinoic acid (RA) treatment. In addition, we found that Neuro-2a cells with overexpression of CA8-S100P and CA8-G162R showed significantly increased neurite outgrowth. Taken together, our data suggest that the expressions of CA8-S100P and CA8-G162R in neuronal cells alter cell morphology, proliferation, mobility and viability; indicating that the homozygous point mutations of CA8 lead to not only the loss of WT CA8 function, but also the gain of novel functions leading to neuromuscular dysfunction.

MRNA Profiling for miR-124-mediated Repair in Spinal Cord Injury

The miRNA miR-124 has been reported to be a promising target for the repair of spinal cord injury (SCI), which is a devastating neurological condition. This study aimed to investigate the underlying molecular mechanisms of miR-124-mediated SCI repair. We established miR-124 SCI model rats and further treated them with agomiR-124 for 14 days. After that, their spinal cords were sectioned, and levels of NeuN, GFAP, and NF-200 were measured via immunofluorescence or via immunohistochemistry. In addition, the spinal dorsal horns were collected for sequencing of total RNA. Differentially expressed (DE) mRNAs were then profiled and a number of these were further verified with qPCR. Gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to predict the potential functions of the DE mRNAs. AgomiR-124 was found to significantly inhibit the decrease of neurons and the activation of astrocytes, while promoting NF-200 expression in the dorsal horn. At fourteen days after agomiR-124 treatment, a total of 85 mRNAs were upregulated and 80 mRNAs were downregulated. We focused our analysis of the DE mRNAs on the top 20 most DE mRNAs, and found four upregulated genes (Nploc4, Yme1l1, LOC103693564, and Aspa) and four downregulated genes (Epb41l2, LOC100911685, LOC100910833, and Smarcc1), which are likely to be of interest to SCI researchers. In addition, we noted that Tal1 is a potential target gene of miR-124, and that a low level of this gene promoted the proliferation of neuronal precursor cells and inhibited their differentiation. In conclusion, miR-124 was able to mediate SCI repair by altering the expression of various mRNAs in rats. The miR-124/Tal1 axis may participate in the treatment of SCI by agomiR-124 by repopulating neural stem cells.

Label-free proteomics differences in the dorsolateral prefrontal cortex between bipolar disorder patients with and without psychosis

BackgroundPsychosis is common in bipolar disorder (BD) and is related to more severe cognitive impairments. Since the molecular mechanism of BD psychosis is elusive, we conducted this study to explore the proteomic differences associated with BD psychosis in the dorsolateral prefrontal cortex (DLPFC; BA9). MethodsPostmortem DLPFC gray matter tissues from five pairs of age-matched male BD subjects with and without psychosis history were used. Tissue proteomes were identified and quantified by label-free liquid chromatography tandem mass spectrometry and then compared between groups. Statistical significance was set at q < 0.40 and Log2 fold change (Log2FC) ≥ |1|. Protein groups with differential expression between groups at p < 0.05 were subjected to pathway analysis. ResultsEleven protein groups differed significantly between groups, including the reduction of tenascin C (q = 0.005, Log2FC = −1.78), the elevations of synaptoporin (q = 0.235, Log2FC = 1.17) and brain-specific angiogenesis inhibitor 1-associated protein 3 (q = 0.241, Log2FC = 2.10) in BD with psychosis. The between-group differences of these proteins were confirmed by Western blots. The top enriched pathways (p < 0.05 with ≥ 3 hits) were the outgrowth of neurons, neuronal cell proliferation, growth of neurites, and outgrowth of neurites, which were all predicted to be upregulated in BD with psychosis. LimitationsSmall sample size and uncertain relationships of the observed proteomic differences with illness stage and acute psychosis. ConclusionsThese results suggested BD with psychosis history may be associated with abnormalities in neurodevelopment, neuroplasticity, neurotransmission, and neuromodulation in the DLPFC.