Project description:Running Head: Genetics, Gut Microbiota, and ALS Progression We investigate the interplay among genetic background, GM composition, metabolism, and immune response in two distinct ALS mouse models: 129Sv_G93A and C57Ola_G93A, representing rapid and slow disease progression, respectively.
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 mouse and human ALS cases. The aim of the present study is to combine LCM and microarray analysis to compare the gene expression profiles of motor neurons from two SOD1G93A mouse strains (129Sv and C57) with different progression of the disease in order to discover the molecular mechanisms that may contribute to the distinct phenotypes and to uncover factors underlying fast and slow disease progression Motor neurons have been isolated from the spinal cord of 129SvG93A mice, C57G93A mice and non transgenic littermates at different time points and the transcription expression profile of the isolated motor neurons has been analysed
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 mouse and human ALS cases. The aim of the present study is to combine LCM and microarray analysis to compare the gene expression profiles of motor neurons from two SOD1G93A mouse strains (129Sv and C57) with different progression of the disease in order to discover the molecular mechanisms that may contribute to the distinct phenotypes and to uncover factors underlying fast and slow disease progression
Project description:Amyotrophic lateral sclerosis (ALS) is a lethal motor neuron disease that progressively debilitates neuronal cells that control voluntary muscle activity. In a mouse model of ALS that expresses mutated human superoxide dismutase 1 (SOD1-G93A) skeletal muscle is one of the tissues affected early by mutant SOD1 toxicity. Fast-twitch and slow-twitch muscles are differentially affected in ALS patients and in the SOD1-G93A model, fast-twitch muscles being more vulnerable. We used miRNA microarrays to investigate miRNA alterations in fast-twitch (EDL) and slow-twitch (soleus) skeletal muscles of symptomatic SOD1-G93A animals and their age-matched wild type littermates. At age of 90 days RNA was extracted from extensor digitorum longus (EDL) and soleus (SOL) muscles of male SOD1-G93A animals and their age-matched wild type male littermates. RNA was hybridized on Affymetrix Multispecies miRNA-2_0 Array.
Project description:Amyotrophic lateral sclerosis (ALS) is a lethal motor neuron disease that progressively debilitates neuronal cells that control voluntary muscle activity. In a mouse model of ALS that expresses mutated human superoxide dismutase 1 (SOD1-G93A) skeletal muscle is one of the tissues affected early by mutant SOD1 toxicity. Fast-twitch and slow-twitch muscles are differentially affected in ALS patients and in the SOD1-G93A model, fast-twitch muscles being more vulnerable. We used miRNA microarrays to investigate miRNA alterations in fast-twitch (EDL) and slow-twitch (soleus) skeletal muscles of symptomatic SOD1-G93A animals and their age-matched wild type littermates.
Project description:The rate of disease progression widely varies between patients with amyotrophic lateral sclerosis (ALS). Prognostic assessment using biomarkers is highly preferred for planning medical care and improving the design of clinical trials. Therefore, the current study aimed to assess prognostic biomarkers for predicting future functional decline in patients with ALS. The prospective progression rate was calculated using the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) at CSF collection and in 6 months. The ALS patients were classified into slow, intermediate, and fast progression groups. We performed comprehensive proteomic analyses of the CSF samples. In total, 26 proteins changed significantly (p < 0.05 and q < 0.10), with levels varying within a large dynamic range (fold change of > 1.5 or < 0.5). A receiver operating characteristic curve analyses showed that the following proteins showed high discrimination power between slow and fast progression groups: GPNMB, GFAP, GPC1, MGAT2, and CHI3L2. Of these, GPNMB, GPC1, and CHI3L2 were significantly correlated to prognostic progression rate. This study demonstrated that CSF levels of neuroinflammation and glycosylation-related proteins were significantly correlated with prospective progression rates in patients with ALS. These proteins could be useful prognostic biomarkers for ALS.
Project description:Extracellular vesicles (EVs) are nanostructures that are used as sources of biomarkers. To better understand whether EVs could be exploited as diagnostic and prognostic biomarkers in Amyotrophic Lateral Sclerosis (ALS), we analyzed plasma-derived of ALS patients and relative healthy and diseased controls. Using the nickel-based isolation, a recently published EV purification method, we unmasked peculiar features in plasma EVs of ALS patients with a potential straightforward application in a clinical setting. We report that the number of particles is increased in the plasma of ALS patients and of two mouse models of ALS while the average diameter is decreased. Proteins like HSP90 and phosphorylated TDP-43 are differentially represented in ALS patients and mice compared to the controls. In terms of disease progression, the levels of phosphorylated TDP-43 and cyclophilin A, along with the EV size distribution discriminated fast and slow progressors of the diseases suggesting a new means for patient stratification. We exploited the EV size distribution with machine learning analysis that combining different EV parameters resulted in very high prediction rates for disease diagnosis and prognosis
Project description:Skeletal muscle denervation is a characteristic feature of neuromuscular diseases such as amyotrophic lateral sclerosis (ALS) and sarcopenia, leading to atrophy, loss of muscle strength, and poor patient outcomes. Myofibers are typically classified into slow oxidative and fast glycolytic types based on their contractile and metabolic properties. Neuromuscular diseases predominantly affect fast myofibers, while slow myofibers are relatively spared. However, the mechanisms underlying the heightened susceptibility of fast myofibers to disease and atrophy remain unclear. To investigate this, we analyzed the transcriptional profiles of innervated and denervated myonuclei. Our findings revealed that the fast muscle gene program and the transcription factor Maf are repressed during denervation. Notably, overexpression of Maf in the skeletal muscles of mice prevented loss of muscle mass and myofiber atrophy caused by denervation. Single-nucleus RNA sequencing and ATAC sequencing demonstrated that Maf overexpression reprogrammed denervated myonuclei by repressing atrophic gene programs and reactivating fast muscle gene expression. Similar repression of fast muscle genes and Maf was observed in muscles from mice and humans with ALS. Consistent with these findings, Maf overexpression in human skeletal muscle cells induced the expression of fast muscle genes while suppressing atrophic gene expression. Our findings highlight a key role for Maf in maintaining muscle mass and demonstrate that its repression contributes to the progression of neuromuscular diseases in both mice and humans. Modulating Maf activity could offer a promising therapeutic strategy to preserve skeletal muscle function during disease, aging, or injury.
Project description:Skeletal muscle denervation is a characteristic feature of neuromuscular diseases such as amyotrophic lateral sclerosis (ALS) and sarcopenia, leading to atrophy, loss of muscle strength, and poor patient outcomes. Myofibers are typically classified into slow oxidative and fast glycolytic types based on their contractile and metabolic properties. Neuromuscular diseases predominantly affect fast myofibers, while slow myofibers are relatively spared. However, the mechanisms underlying the heightened susceptibility of fast myofibers to disease and atrophy remain unclear. To investigate this, we analyzed the transcriptional profiles of innervated and denervated myonuclei. Our findings revealed that the fast muscle gene program and the transcription factor Maf are repressed during denervation. Notably, overexpression of Maf in the skeletal muscles of mice prevented loss of muscle mass and myofiber atrophy caused by denervation. Single-nucleus RNA sequencing and ATAC sequencing demonstrated that Maf overexpression reprogrammed denervated myonuclei by repressing atrophic gene programs and reactivating fast muscle gene expression. Similar repression of fast muscle genes and Maf was observed in muscles from mice and humans with ALS. Consistent with these findings, Maf overexpression in human skeletal muscle cells induced the expression of fast muscle genes while suppressing atrophic gene expression. Our findings highlight a key role for Maf in maintaining muscle mass and demonstrate that its repression contributes to the progression of neuromuscular diseases in both mice and humans. Modulating Maf activity could offer a promising therapeutic strategy to preserve skeletal muscle function during disease, aging, or injury.