Expression data of isolated motor neurons from SOD1 G93A mice, after G-CSF treatment
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ABSTRACT: Gene expression changes in spinal motor neurons of the SOD1G93A-transgenic model for ALS after treatment with G-CSF. To gain insight into the mode of action of G-CSF, we performed gene expression profiling on isolated lumbar motor neurons from SOD1G93A mice, the most frequently studied animal model for ALS, with and without G-CSF treatment.
Project description:Familial amyotrophic lateral sclerosis (ALS) represents about 10% of ALS cases. In about 20% of familial ALS patients, a mutation in superoxide dismutase-1 (SOD1) can be found. The ubiquitous SOD1 protein converts superoxide radical anions to oxygen and hydrogen peroxide. Patients with familial ALS caused by mutations in SOD1 can show comorbidity with frontotemporal dementia and develop cognitive impairment, including apathy, inattention, verbal deficits, and hypersexuality. At the cellular level, pathological signs of ALS may include tau immunoreactive astrocytic and neuronal inclusions, suggesting that cognitive dysfunction in ALS may also reflect abnormal protein metabolism of the microtubule associated protein (MAP), tau. To identify cell-specific expression changes, we performed laser capture microdissection (LCM) to isolate anterior horn motor neurons and surrounding cells. To determine common pathways for the development of ALS due to dysfunction of SOD1 or TAU, we performed whole transcriptome analysis in SOD1 and TAU mouse models. Because ALS is a neurodegenerative disease that specifically affects motor neurons, these cells were the main investigative target. Global transcriptomes of glial cells surrounding the motor neurons were also assessed, because these cells have been implicated as triggers of neurodegeneration. Mouse experiments were performed at the presymptomatic stage, prior to the onset of cell loss, in order to reduce false positive signals due to tissue reactive changes. Lumbar anterior horn anterior horn motor neurons and surrounding cells (glia) were isolated from presymptomatic TAU-P301L and SOD1-G93A transgenic mice using laser capture microdissection (LCM; PixCell® IIe LCM System, Arcturus, Molecular Devices, CA). On average, 500 motor neuron bodies or surrounding glial cells from 20 tissue sections per animal were collected. RNA isolation from LCM collected cells was performed using the Qiagen RNeasy Micro Kit. Only RNA with RNA Integrity Numbers (RIN) above 7.5 were taken for further analysis (Agilent Bioanalyzer 2100). A two-round T7-based amplification and labeling protocol (Agilent Low RNA Input Linear Amplification Kit PLUS) was used to generate high quality labeled cRNA. Agilent Whole Mouse Genome Microarray comparisons of motor neurons and surrounding glia were performed between transgenic (SOD1G93A and TAUP301L) and corresponding nontransgenic (control) littermate animals, producing four independent comparison groups: SOD1G93A motor neurons versus control motor neurons (SOD1mn), SOD1G93A motor neuron surrounding glia versus control glia (SOD1gl), TAUP301L motor neurons versus control motor neurons (TAUmn) and TAUP301L glia versus control glia (TAUgl). Each comparison used four pairs of transgenic (SOD1G93A or TAUP301L) vs. corresponding control littermate animals, producing four biological replicates. Raw microarray data were acquired using the Agilent DNA Microarray scanner and processed with the accompanying Agilent Feature Extraction 10.5 Image Analysis software using default settings. Normalized signal intensities were used to identify gene expression changes in SOD1G93A and TAUP301L motor neurons and surrounding glial cells, generating four partially overlapping sets of data. For the identification of differential expression, the genes were required to pass two conservative criteria: a ratio beyond the 99.5% confidence interval observed in homotypic comparisons, which corresponded to an approximately 1.5-fold expression change, and a paired t-test (P<0.01) computed using 100 permutations of the data for each gene. Correction for multiple comparisons was performed using the adjusted Bonferroni test. The analysis was performed in the TM4: Microarray Software Suite. These techniques identified 251 transcripts representing 186 known genes for which expression was altered in at least one of the four comparisons. Four-condition experiment, SOD1G93A motor neurons versus control motor neurons (SODmn), SOD1G93A motor neuron surrounding glia versus control glia (SODgl), TAUP301L motor neurons versus control motor neurons (TAUmn) and TAUP301L glia versus control glia (TAUgl). Each comparison used four pairs of transgenic (SOD1G93A or TAUP301L) vs. corresponding control littermate animals, producing four biological replicates. Biological replicates: 4 SOD1G93A motor neurons (SODmn), 4 non SOD littermate motor neurons (nonSODmn), 4 SOD1G93A motor neuron surrounding glia (SODgl), 4 non SOD littermate motor neuron surrounding glia (nonSODgl), 4 TAUP301L motor neurons (TAUmn), 4 non TAU littermate motor neurons (nonTAUmn), 4 TAUP301L motor neuron surrounding glia (TAUgl), 4 non TAU littermate motor neuron surrounding glia (nonTAUgl). Four independent comparison groups were generated: SOD1G93A motor neurons versus control nonSOD motor neurons, SOD1G93A motor neuron surrounding glia versus control nonSOD glia, TAUP301L motor neurons versus control nonTAU motor neurons and TAUP301L glia versus control nonTAU glia. Each comparison used four pairs of transgenic (SOD1G93A or TAUP301L) vs. corresponding control littermate animals, producing four biological replicates. Each replicate was repeated twice with dye flip to correct for unequal dye incorporation rates. Therefore, eight microarray hybridizations were performed for each biological comparison, for a total of 32 microarray slides and generating four groups of differentially expressed genes in SOD1G93A motor neurons (SODmn), SOD1G93A motor neuron surrounding glial cells (SODgl), TAUP301L motor neurons (TAUmn), and TAUP301L surrounding glial cells (TAUgl).
Project description:Gene expression changes in spinal motor neurons of the SOD1G93A-transgenic model for ALS after treatment with G-CSF. To gain insight into the mode of action of G-CSF, we performed gene expression profiling on isolated lumbar motor neurons from SOD1G93A mice, the most frequently studied animal model for ALS, with and without G-CSF treatment. A first group of SOD1G93A and WT mice was included in the study at week 11 of age when SOD1G93A mice present no signs of motor dysfunction but subtle signs of denervation detectable by electromyography. The second cohort of mice was treated with G-CSF or vehicle from week 11 to week 15. At the time of study completion, SOD1G93A mice presented clear motor impairment and motor neuron degeneration is documented. This design should provide information on genes altered in motor neurons of SOD1G93A mice from the clinically non-symptomatic to an early symptomatic stage, and give insight into genes influenced by G-CSF treatment. We sampled 300 motoneurons per mouse spinal cord by laser microdissection.
Project description:Familial amyotrophic lateral sclerosis (ALS) represents about 10% of ALS cases. In about 20% of familial ALS patients, a mutation in superoxide dismutase-1 (SOD1) can be found. The ubiquitous SOD1 protein converts superoxide radical anions to oxygen and hydrogen peroxide. Patients with familial ALS caused by mutations in SOD1 can show comorbidity with frontotemporal dementia and develop cognitive impairment, including apathy, inattention, verbal deficits, and hypersexuality. At the cellular level, pathological signs of ALS may include tau immunoreactive astrocytic and neuronal inclusions, suggesting that cognitive dysfunction in ALS may also reflect abnormal protein metabolism of the microtubule associated protein (MAP), tau. To identify cell-specific expression changes, we performed laser capture microdissection (LCM) to isolate anterior horn motor neurons and surrounding cells. To determine common pathways for the development of ALS due to dysfunction of SOD1 or TAU, we performed whole transcriptome analysis in SOD1 and TAU mouse models. Because ALS is a neurodegenerative disease that specifically affects motor neurons, these cells were the main investigative target. Global transcriptomes of glial cells surrounding the motor neurons were also assessed, because these cells have been implicated as triggers of neurodegeneration. Mouse experiments were performed at the presymptomatic stage, prior to the onset of cell loss, in order to reduce false positive signals due to tissue reactive changes. Lumbar anterior horn anterior horn motor neurons and surrounding cells (glia) were isolated from presymptomatic TAU-P301L and SOD1-G93A transgenic mice using laser capture microdissection (LCM; PixCell® IIe LCM System, Arcturus, Molecular Devices, CA). On average, 500 motor neuron bodies or surrounding glial cells from 20 tissue sections per animal were collected. RNA isolation from LCM collected cells was performed using the Qiagen RNeasy Micro Kit. Only RNA with RNA Integrity Numbers (RIN) above 7.5 were taken for further analysis (Agilent Bioanalyzer 2100). A two-round T7-based amplification and labeling protocol (Agilent Low RNA Input Linear Amplification Kit PLUS) was used to generate high quality labeled cRNA. Agilent Whole Mouse Genome Microarray comparisons of motor neurons and surrounding glia were performed between transgenic (SOD1G93A and TAUP301L) and corresponding nontransgenic (control) littermate animals, producing four independent comparison groups: SOD1G93A motor neurons versus control motor neurons (SOD1mn), SOD1G93A motor neuron surrounding glia versus control glia (SOD1gl), TAUP301L motor neurons versus control motor neurons (TAUmn) and TAUP301L glia versus control glia (TAUgl). Each comparison used four pairs of transgenic (SOD1G93A or TAUP301L) vs. corresponding control littermate animals, producing four biological replicates. Raw microarray data were acquired using the Agilent DNA Microarray scanner and processed with the accompanying Agilent Feature Extraction 10.5 Image Analysis software using default settings. Normalized signal intensities were used to identify gene expression changes in SOD1G93A and TAUP301L motor neurons and surrounding glial cells, generating four partially overlapping sets of data. For the identification of differential expression, the genes were required to pass two conservative criteria: a ratio beyond the 99.5% confidence interval observed in homotypic comparisons, which corresponded to an approximately 1.5-fold expression change, and a paired t-test (P<0.01) computed using 100 permutations of the data for each gene. Correction for multiple comparisons was performed using the adjusted Bonferroni test. The analysis was performed in the TM4: Microarray Software Suite. These techniques identified 251 transcripts representing 186 known genes for which expression was altered in at least one of the four comparisons.
Project description:To investigate the role of motor neuron autophagy in ALS, we generated mice in which the critical autophagy gene Atg7 was specifically disrupted in motor neurons (Atg7 cKO). We also bred these mice to the SOD1G93A mouse model of ALS. Then we performed RNA sequencing on lumbar spinal cords from these mice to determine how motor neuron autophagy inhibition altered gene expression.
Project description:Microarray analysis has been applied to the study of ALS in order to investigate gene expression in whole spinal cord homogenates of SOD1 G93A mice and human ALS cases, although the massive presence of glial cells and inflammatory factors has made it difficult to define which gene expression changes were motor neuron specific. Recently, laser capture microdissection (LCM), combined with microarray analysis, has allowed the identification of motor neuron specific changes in gene expression in human ALS cases. The aim of the present study is to combine LCM and microarray analysis to study how motor neurons in the spinal cord of transgenic SOD1 G93A mice and transgenic SOD1 WT respond to stimuli determined by the presence of the human mutant protein throughout the evolution of the stages in motor neuron injury Experiment Overall Design: Motor neurons have been isolated from the spinal cord of G93A mice and non transgenic littermates at different time points and the transcription expression profile of the isolated motor neurons has been analysed
Project description:Gene expression profiling has been performed previously on motor cortex and spinal cord homogenates and of sporadic ALS cases and controls, to identify genes and pathways differentially expressed in ALS. More recent studies have combined the use of laser capture microdissection (LCM) with gene expression profiling to isolate the motor neurons from the surrounding cells, such as microglia and astrocytes, in order to determine those genes differentially expressed in the vulnerable cell population – i.e. motor neuron. The aim of the present study is to combine LCM and microarray analysis to determine those genes and pathways differentially expressed in MNs from human SOD1-related MND and to establish potential pathways for therapeutic intervention. Keywords: Human motor neurons The aim of this study was to determine the gene expression profiles from a small subset of cases which all carry mutations in the SOD1 gene. Expression profiles from isolated motor neurons in SOD1-related ALS cases were compared to those from control motor neurons, in order to establish the pathways implicated in SOD1-related motor neuronal cell death. The 'control' samples were originally submitted to GEO as GSE19332.
Project description:Mitochondria from affected tissues of Amyotrophic Lateral Sclerosis (ALS) patients show morphological and biochemical abnormalities. The impairment of mitochondrial functions causes oxidative damage and accumulation of ROS and represents one of the major features that lead to the selective death of motor neurons in ALS. Our aim was to assess the ability of oxidative stress found in ALS to induce post-translational modifications (PTMs) in VDAC1, the main protein of the outer mitochondrial membrane and known to interact with SOD1 mutants related to ALS. In this work, specific post-translational modifications (PTMs) of the VDAC1 protein purified by hydroxyapatite from mitochondria of a NSC34 cell line expressing human SOD1G93A, a suitable ALS motor neurons model, were analyzed by tryptic and chymotryptic proteolysis and UHPLC/High Resolution ESI-MS/MS. Selective deamidations of asparagine and glutamine of VDAC1 in ALS-related NSC34-SOD1G93A cells but not in NSC34-SOD1 or NSC34wt cells were found. In addition, we identified differences in the over-oxidation of methionine and cysteines between VDAC1 purified from ALS model or non-ALS NSC34 cells. The specific range of PTMs identified exclusively in VDAC1 from NSC34-SOD1G93A cells but not fromNSC34control lines, suggests the appearance of important changes to the structure of the VDAC1 channel and therefore to the bioenergetics metabolism of ALS motor neurons.
Project description:Amyotrophic lateral sclerosis (ALS) is caused by the progressive degeneration of motor neurons. Mutations in the Cu/Zn superoxide dismutase (SOD1) are found in about 20% of patients with familial ALS. Mutant SOD1 causes motor neuron death through an acquired toxic property. Although, molecular mechanism underlying this toxic gain-of-function remains unknown, evidence support the role of mutant SOD1 expression in non-neuronal cells in shaping motor neuron degeneration. We have previously found that in contrast to non-transgenic, SOD1G93A-expressing astrocytes induced apoptosis of co-cultured motor neurons. This prompted us to investigate whether the effect on motor neuron survival was related to a change in the gene expression profile. Through high-density oligonucletide microarrays we found changes in the expression of genes involved in transcription, signaling, cell proliferation, extracellular matrix construction, response to stress and steroid and lipid metabolism. Decorin, a small multifunctional proteoglycan, was the most up-regulated gene. Down-regulated genes included the insulin-like growth factor-1 receptor and the RNA binding protein ROD1. We also analyzed the expression of selected genes in purified motor neurons expressing SOD1G93A and in spinal cord of asymptomatic and early symptomatic ALS-rodent model. The expression of mutated SOD1 in astrocytes cause gene expression changes with potential consequences for its interaction with motor neurons. The astrocyte-specific gene expression profile contributes to the identification of possible candidates for cell type-specific therapies in ALS Keywords: Cell type comparison
Project description:A consistent clinical feature of amyotrophic lateral sclerosis (ALS) is the sparing of eye movements. Pathological studies have confirmed that there is relative sparing of the cranial motor nuclei of the oculomotor, trochlear and abducens nerves, although pathological changes resembling those seen in anterior horn cells are present to a lesser degree. The aim of the present study is to combine LCM and microarray analysis to study the differences between motor neurons that are selectively resistant (oculomotor neurons) and those that are vulnerable (lumbar spinal motor neurons) to the disease process in amyotrophic lateral sclerosis. We used microarray analysis to determine the differences in gene expression between oculomotor and lumbar spinal motor neurons, isolated by laser capture microdissection from the midbrain and spinal cord of neurologically normal human controls.
Project description:Early molecular events related to cytoskeleton are poorly described in Amyotrophic Lateral Sclerosis (ALS), especially in the Schwann cell (SC), which offers strong trophic support to motor neurons. DAVID tool identified cytoskeleton-related genes by employing the Cellular Component of Gene Ontology (CCO) in a large gene profiling of lumbar spinal cord and sciatic nerve of presymptomatic SOD1G93A mice. One and five CCO terms related to cytoskeleton were described from the spinal cord deregulated genes of 40 days (actin cytoskeleton) and 80 days (microtubule cytoskeleton, cytoskeleton part, actin cytoskeleton, neurofilament cytoskeleton and cytoskeleton) old transgene mice, respectively. Also, four terms were depicted from the deregulated genes of sciatic nerve of 60 days old transgenes (actin cytoskeleton, cytoskeleton part, microtubule cytoskeleton and cytoskeleton). Kif1b was the unique gene that appeared deregulated in more than one studied region or presymptomatic age. The expression of Kif1b (qPCR) elevated in the lumbar spinal cord (40 days old) and decreased in the sciatic nerve (60 days old) of presymptomatic ALS mice, results that were in line to microarray findings. Upregulation (24.8 fold) of Kif1b was seen in laser microdissected enriched immunolabeled motor neurons from the spinal cord of 40 days old presymptomatic SOD1G93A mice. Furthermore, Kif1b was downregulated in the sciatic nerve Schwann cells of presymptomatic ALS mice (60 days old) that were enriched by means of cell microdissection (6.35 fold), cell sorting (3.53 fold) and primary culture (2.70 fold) technologies. The gene regulation of cytoskeleton molecules is an important occurrence in motor neurons and Schwann cells in presymptomatic stages of ALS and may be relevant in the dying back mechanisms of neuronal death. Differential regulation of Kif1b in the spinal cord and sciatic nerve cells emerged as key event in ALS. Sciatic nerve from SOD1G93A and Non transgenic controls from 60 days were used in the experiments. 4 biological replicates were used. A reference sample, comprised by RNA from different neonatal organs (heart, liver, kidney) were used in the hybridations