In vitro exposure to PM2.5 of olfactory Ensheathing cells and SH-SY5Y cells and possible association with neurodegenerative processes.

PM2.5 exposure represents a risk factor for the public health. PM2.5 is able to cross the blood-alveolar and blood-brain barriers and reach the brain through three routes: nasal olfactory pathway, nose-brain pathway, blood-brain barrier pathway. We evaluated the effect of PM2.5 to induce cytotoxicity and reduced viability on in vitro cultures of OECs (Olfactory Ensheathing Cells) and SH-SY5Y cells. PM2.5 samples were collected in the metropolitan area of Catania, and the gravimetric determination of PM2.5, characterization of 10 trace elements and 16 polycyclic aromatic hydrocarbons (PAHs) were carried out for each sample. PM2.5 extracts were exposed to cultures of OECs and SH-SY5Y cells for 24-48-72 h, and the cell viability assay (MTT) was evaluated. Assessment of mitochondrial and cytoskeleton damage, and the assessment of apoptotic process were performed in the samples that showed lower cell viability. We have found an annual average value of PM2.5 = 16.9 µg/m3 and a maximum value of PM2.5 = 27.6 µg/m3 during the winter season. PM2.5 samples collected during the winter season also showed higher concentrations of PAHs and trace elements. The MTT assay showed a reduction in cell viability for both OECs (44%, 62%, 64%) and SH-SY5Y cells (16%, 17%, 28%) after 24-48-72 h of PM2.5 exposure. Furthermore, samples with lower cell viability showed a decrease in mitochondrial membrane potential, increased cytotoxicity, and also impaired cellular integrity and induction of the apoptotic process after increased expression of vimentin and caspase-3 activity, respectively. These events are involved in neurodegenerative processes and could be triggered not only by the concentration and time of exposure to PM2.5, but also by the presence of trace elements and PAHs on the PM2.5 substrate. The identification of more sensitive cell lines could be the key to understanding how exposure to PM2.5 can contribute to the onset of neurodegenerative processes.

The ε-Isozyme of Protein Kinase C (PKCε) Is Impaired in ALS Motor Cortex and Its Pulse Activation by Bryostatin-1 Produces Long Term Survival in Degenerating SOD1-G93A Motor Neuron-like Cells.

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and ultimately fatal neurodegenerative disease, characterized by a progressive depletion of upper and lower motor neurons (MNs) in the brain and spinal cord. The aberrant regulation of several PKC-mediated signal transduction pathways in ALS has been characterized so far, describing either impaired expression or altered activity of single PKC isozymes (α, ß, ζ and δ). Here, we detailed the distribution and cellular localization of the ε-isozyme of protein kinase C (PKCε) in human postmortem motor cortex specimens and reported a significant decrease in both PKCε mRNA (PRKCE) and protein immunoreactivity in a subset of sporadic ALS patients. We furthermore investigated the steady-state levels of both pan and phosphorylated PKCε in doxycycline-activated NSC-34 cell lines carrying the human wild-type (WT) or mutant G93A SOD1 and the biological long-term effect of its transient agonism by Bryostatin-1. The G93A-SOD1 cells showed a significant reduction of the phosphoPKCε/panPKCε ratio compared to the WT. Moreover, a brief pulse activation of PKCε by Bryostatin-1 produced long-term survival in activated G93A-SOD1 degenerating cells in two different cell death paradigms (serum starvation and chemokines-induced toxicity). Altogether, the data support the implication of PKCε in ALS pathophysiology and suggests its pharmacological modulation as a potential neuroprotective strategy, at least in a subgroup of sporadic ALS patients.

CXCR2 increases in ALS cortical neurons and its inhibition prevents motor neuron degeneration in vitro and improves neuromuscular function in SOD1G93A mice.

Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease characterized by depletion of motor neurons (MNs), for which effective medical treatments are still required. Previous transcriptomic analysis revealed the up-regulation of C-X-C motif chemokine receptor 2 (CXCR2)-mRNA in a subset of sporadic ALS patients and SOD1G93A mice. Here, we confirmed the increase of CXCR2 in human ALS cortex, and showed that CXCR2 is mainly localized in cell bodies and axons of cortical neurons. We also investigated the effects of reparixin, an allosteric inhibitor of CXCR2, in degenerating human iPSC-derived MNs and SOD1G93A mice. In vitro, reparixin rescued MNs from apoptotic cell death, preserving neuronal morphology, mitochondrial membrane potential and cytoplasmic membrane integrity, whereas in vivo it improved neuromuscular function of SOD1G93A mice. Altogether, these data suggest a role for CXCR2 in ALS pathology and support its pharmacological inhibition as a candidate therapeutic strategy against ALS at least in a specific subgroup of patients.

The contribution of CNVs to the most common aging-related neurodegenerative diseases.

Alzheimer and Parkinson's diseases are neurodegenerative aging-related pathological conditions, mainly caused by the interplay of genetic and non-genetic factors and whose incidence rate is going to drastically increase given the growing life expectancy. To address these complex multifactorial traits, a systems biology strategy is needed to highlight genotype-phenotype correlations as well as overlapping gene signatures. Copy number variants (CNVs) are structural chromosomal imbalances that can have pathogenic nature causing or contributing to the disease onset or progression. Moreover, neurons affected by CNVs have been found to decline in number depending on age in healthy controls and may be selectively vulnerable to aging-related cell-death. In this review, we aim to update the reader on the role of these variations in the pathogenesis of Alzheimer and Parkinson diseases. To widen the comprehension of pathogenic mechanisms underlying them, we discuss variations detected from blood or brain specimens, as well as overlapped signatures between the two pathologies.

Omics Data and Their Integrative Analysis to Support Stratified Medicine in Neurodegenerative Diseases.

Molecular and clinical heterogeneity is increasingly recognized as a common characteristic of neurodegenerative diseases (NDs), such as Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis. This heterogeneity makes difficult the development of early diagnosis and effective treatment approaches, as well as the design and testing of new drugs. As such, the stratification of patients into meaningful disease subgroups, with clinical and biological relevance, may improve disease management and the development of effective treatments. To this end, omics technologies-such as genomics, transcriptomics, proteomics and metabolomics-are contributing to offer a more comprehensive view of molecular pathways underlying the development of NDs, helping to differentiate subtypes of patients based on their specific molecular signatures. In this article, we discuss how omics technologies and their integration have provided new insights into the molecular heterogeneity underlying the most prevalent NDs, aiding to define early diagnosis and progression markers as well as therapeutic targets that can translate into stratified treatment approaches, bringing us closer to the goal of personalized medicine in neurology.

Design and Validation of a Custom NGS Panel Targeting a Set of Lysosomal Storage Diseases Candidate for NBS Applications.

Lysosomal storage diseases (LSDs) are a heterogeneous group of approximately 70 monogenic metabolic disorders whose diagnosis represents an arduous challenge for clinicians due to their variability in phenotype penetrance, clinical manifestations, and high allelic heterogeneity. In recent years, the approval of disease-specific therapies and the rapid emergence of novel rapid diagnostic methods has opened, for a set of selected LSDs, the possibility for inclusion in extensive national newborn screening (NBS) programs. Herein, we evaluated the clinical utility and diagnostic validity of a targeted next-generation sequencing (tNGS) panel (called NBS_LSDs), designed ad hoc to scan the coding regions of six genes (GBA, GAA, SMPD1, IDUA1, GLA, GALC) relevant for a group of LSDs candidate for inclusion in national NBS programs (MPSI, Pompe, Fabry, Krabbe, Niemann Pick A-B and Gaucher diseases). A standard group of 15 samples with previously known genetic mutations was used to test and validate the entire flowchart. Analytical accuracy, sensitivity, and specificity, as well as turnaround time and costs, were assessed. Results showed that the Ion AmpliSeq and Ion Chef System-based high-throughput NBS_LSDs tNGS panel is a fast, accurate, and cost-effective process. The introduction of this technology into routine NBS procedures as a second-tier test along with primary biochemical assays will allow facilitating the identification and management of selected LSDs and reducing diagnostic delay.

iPSCs: A Preclinical Drug Research Tool for Neurological Disorders.

The development and commercialization of new drugs is an articulated, lengthy, and very expensive process that proceeds through several steps, starting from target identification, screening new leading compounds for testing in preclinical studies, and subsequently in clinical trials to reach the final approval for therapeutic use. Preclinical studies are usually performed using both cell cultures and animal models, although they do not completely resume the complexity of human diseases, in particular neurodegenerative conditions. To this regard, stem cells represent a powerful tool in all steps of drug discovery. The recent advancement in induced Pluripotent Stem Cells (iPSCs) technology has opened the possibility to obtain patient-specific disease models for drug screening and development. Here, we report the use of iPSCs as a disease model for drug development in the contest of neurological disorders, including Alzheimer's (AD) and Parkinson's disease (PD), Amyotrophic lateral Sclerosis (ALS), and Fragile X syndrome (FRAX).

Dental mesenchymal stem cells and neuro-regeneration: a focus on spinal cord injury.

Regenerative medicine is a branch of translational research that aims to reestablish irreparably damaged tissues and organs by stimulating the body's own repair mechanisms via the implantation of stem cells differentiated into specialized cell types. A rich source of adult stem cells is located inside the tooth and is represented by human dental pulp stem cells, or hDPSCs. These cells are characterized by a high proliferative rate, have self-renewal and multi-lineage differentiation properties and are often used for tissue engineering and regenerative medicine. The present review will provide an overview of hDPSCs and related features with a special focus on their potential applications in regenerative medicine of the nervous system, such as, for example, after spinal cord injury. Recent advances in the identification and characterization of dental stem cells and in dental tissue engineering strategies suggest that bioengineering approaches may successfully be used to regenerate districts of the central nervous system, previously considered irreparable.

Alternative Splicing of ALS Genes: Misregulation and Potential Therapies.

Neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS), spinal muscular atrophy (SMA), Parkinson's, Alzheimer's, and Huntington's disease affect a rapidly increasing population worldwide. Although common pathogenic mechanisms have been identified (e.g., protein aggregation or dysfunction, immune response alteration and axonal degeneration), the molecular events underlying timing, dosage, expression, and location of RNA molecules are still not fully elucidated. In particular, the alternative splicing (AS) mechanism is a crucial player in RNA processing and represents a fundamental determinant for brain development, as well as for the physiological functions of neuronal circuits. Although in recent years our knowledge of AS events has increased substantially, deciphering the molecular interconnections between splicing and ALS remains a complex task and still requires considerable efforts. In the present review, we will summarize the current scientific evidence outlining the involvement of AS in the pathogenic processes of ALS. We will also focus on recent insights concerning the tuning of splicing mechanisms by epigenomic and epi-transcriptomic regulation, providing an overview of the available genomic technologies to investigate AS drivers on a genome-wide scale, even at a single-cell level resolution. In the future, gene therapy strategies and RNA-based technologies may be utilized to intercept or modulate the splicing mechanism and produce beneficial effects against ALS.

Molecular mechanisms involved in the protective effect of pituitary adenylate cyclase-activating polypeptide in an in vitro model of amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the loss of upper and lower motor neurons. Based on transcriptional profiles of motor cortex samples, in a previous work, we were able to classify two subgroups of sporadic ALS (SALS) patients, named SALS1 and SALS2. A further meta-analysis study has revealed sixteen drug targets commonly deregulated in SALS2 and superoxide dismutase 1 (SOD1) G93A mice. The identified candidate drug targets included pituitary adenylate cyclase-activating polypeptide (PACAP), epidermal growth factor receptor (EGFR) and matrix metallopeptidase-2 (MMP-2). By using a motor neuron-like hybrid cell line (NSC-34) expressing human SOD1 G93A as an in vitro model of ALS, here we investigated the functional correlation among these three genes. Our results have shown that PACAP increases cell viability following serum deprivation. This effect is induced through EGFR transactivation mediated by protein kinase A stimulation. Furthermore, EGFR phosphorylation activates mitogen-activated protein kinases/extracellular signal-regulated kinases 1 and 2 survival signaling pathway and increases MMP-2 expression, significantly reduced by serum starvation. These results suggest that a deeper characterization of mechanisms involved in PACAP/EGFR/MMP-2 axis activation in G93A SOD1 mutated neurons may allow identifying new targets for ALS therapy.

NAP counteracts hyperglycemia/hypoxia induced retinal pigment epithelial barrier breakdown through modulation of HIFs and VEGF expression.

Diabetic macular edema (DME) is a common complication leading to a central vision loss in patients with diabetes. In this eye pathology, the hyperglycaemic/hypoxic microenvironment of pigmented epithelium is responsible for outer blood retinal barrier integrity changes. More recently, we have shown that a small peptide derived from the activity-dependent neuroprotective protein (ADNP), known as NAP, counteracts damages occurring during progression of diabetic retinopathy by modulating HIFs/VEGF pathway. Here, we have investigated for the first time the role of this peptide on outer blood retinal barrier (BRB) integrity exposed to hyperglycaemic/hypoxic insult mimicking a model in vitro of DME. To characterize NAP role on disease's pathogenesis, we have analyzed its effect on HIFs/VEGF system in human retinal pigmented epithelial cells, ARPE-19, grown in high glucose and low oxygen tension. The results have shown that NAP prevents outer BRB breakdown by reducing HIF1α/HIF2α, VEGF/VEGFRs, and increasing HIF3α expression, moreover it is able to reduce the percentage of apoptotic cells by modulating the expression of two death related genes, BAX and Bcl2. Further investigations are needed to determine the possible use of NAP in DME treatment.

PACAP and PAC1R are differentially expressed in motor cortex of amyotrophic lateral sclerosis patients and support survival of iPSC-derived motor neurons.

Amyotrophic lateral sclerosis (ALS) is a fatal and disabling neurodegenerative disease characterized by upper and lower motor neurons depletion. In our previous work, comprehensive genomic profiling of 41 motor cortex samples enabled to discriminate controls from sporadic ALS patients, and segregated these latter into two distinct subgroups (SALS1 and SALS2), each associated with different deregulated genes. In the present study, we focused our attention on two of them, Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) and its type 1 receptor (PAC1R), and validated the results of the transcriptome experiments by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), immunohistochemistry and Western blot analysis. To assess the functional role of PACAP and PAC1R in ALS, we developed an in vitro model of human induced pluripotent stem cells (iPSC)-derived motor neurons and examined the trophic effects of exogenous PACAP following neurodegenerative stimuli. Treatment with 100 nm PACAP was able to effectively rescue iPSC-derived motor neurons from apoptosis, as shown by cell viability assay and protein dosage of the apoptotic marker (BAX). All together, these data suggest that perturbations in the PACAP-PAC1R pathway may be involved in ALS pathology and represent a potential drug target to enhance motor neuron viability.

Differential expression of PARK2 splice isoforms in an in vitro model of dopaminergic-like neurons exposed to toxic insults mimicking Parkinson's disease.

Mutations in PARK2 (or parkin) are responsible for 50% of cases of autosomal-recessive juvenile-onset Parkinson's disease (PD). To date, 21 alternative splice variants of the human gene have been cloned. Yet most studies have focused on the full-length protein, whereas the spectrum of the parkin isoforms expressed in PD has never been investigated. In this study, the role of parkin proteins in PD neurodegeneration was explored for the first time by analyzing their expression profile in an in vitro model of PD. To do so, undifferentiated and all-trans-retinoic-acid (RA)-differentiated SH-SY5Y cells (which thereby acquire a PD-like phenotype) were exposed to PD-mimicking neurotoxins: 1-methyl-4-phenylpyridinium (MPP+ ) and 6-hydroxydopamine (6-OHDA) are widely used in PD models, whereas carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and carbobenzoxy-Leu-Leu-leucinal (MG132) interfere, respectively, with mitochondrial mitophagy and proteasomal degradation. Following treatment with each neurotoxin H1, the first parkin isoform to be cloned, was down-regulated compared to the respective controls both in undifferentiated and RA-differentiated cells. In contrast, the expression pattern of the minor splice isoforms varied as a function of the compound used: it was largely unchanged in both cell cultures (eg, H21-H6, H12, XP isoform) or it showed virtually opposite alterations in undifferentiated and RA-differentiated cells (eg, H20 and H3 isoform). This complex picture suggests that up- or down-regulation may be a direct effect of toxin exposure, and that the different isoforms may exert different actions in neurodegeneration via modulation of different molecular pathways.

NeuroArray: A Customized aCGH for the Analysis of Copy Number Variations in Neurological Disorders.

BACKGROUND: Neurological disorders are a highly heterogeneous group of pathological conditions that affect both the peripheral and the central nervous system. These pathologies are characterized by a complex and multifactorial etiology involving numerous environmental agents and genetic susceptibility factors. For this reason, the investigation of their pathogenetic basis by means of traditional methodological approaches is rather arduous. High-throughput genotyping technologies, including the microarray-based comparative genomic hybridization (aCGH), are currently replacing classical detection methods, providing powerful molecular tools to identify genomic unbalanced structural rearrangements and explore their role in the pathogenesis of many complex human diseases. METHODS: In this report, we comprehensively describe the design method, the procedures, validation, and implementation of an exon-centric customized aCGH (NeuroArray 1.0), tailored to detect both single and multi-exon deletions or duplications in a large set of multi- and monogenic neurological diseases. This focused platform enables a targeted measurement of structural imbalances across the human genome, targeting the clinically relevant genes at exon-level resolution. CONCLUSION: An increasing use of the NeuroArray platform may offer new insights in investigating potential overlapping gene signatures among neurological conditions and defining genotype-phenotype relationships.

Caffeine Prevents Blood Retinal Barrier Damage in a Model, In Vitro, of Diabetic Macular Edema.

Diabetic macular edema (DME) is the major cause of vision loss in patients affected by diabetic retinopathy. Hyperglycemia and hypoxia represent the key elements in the progression of these pathologies, leading to breakdown of the blood-retinal barrier (BRB). Caffeine, a psychoactive substance largely consumed in the world, is a nonselective antagonist of adenosine receptors (AR) and it possesses a protective effect in various diseases, including eye pathologies. Here, we have investigated the effect of this substance on BRB integrity following exposure to hyperglycemic/hypoxic insult. Retinal pigmented epithelial cells, ARPE-19, have been grown on semi-permeable supports mimicking an experimental model, in vitro, of outer BRB. Caffeine treatment has reduced cell monolayer permeability after exposure to high glucose and desferoxamine as shown by TEER and FITC-dextran permeability assays. This effect is also mediated through the restoration of membrane's tight junction expression, ZO-1. Moreover, we have demonstrated that caffeine is able to prevent outer BRB damage by inhibiting apoptotic cell death induced by hyperglycemic/hypoxic insult since it downregulates the proapoptotic Bax and upregulates the anti-apoptotic Bcl-2 genes. Although further studies are needed to better comprise the beneficial effect of caffeine, we can speculate that it might be used as an innovative drug for DME treatment. J. Cell. Biochem. 118: 2371-2379, 2017. © 2017 Wiley Periodicals, Inc.

Copy number variability in Parkinson's disease: assembling the puzzle through a systems biology approach.

Parkinson's disease (PD), the second most common progressive neurodegenerative disorder of aging, was long believed to be a non-genetic sporadic origin syndrome. The proof that several genetic loci are responsible for rare Mendelian forms has represented a revolutionary breakthrough, enabling to reveal molecular mechanisms underlying this debilitating still incurable condition. While single nucleotide polymorphisms (SNPs) and small indels constitute the most commonly investigated DNA variations accounting for only a limited number of PD cases, larger genomic molecular rearrangements have emerged as significant PD-causing mutations, including submicroscopic Copy Number Variations (CNVs). CNVs constitute a prevalent source of genomic variations and substantially participate in each individual's genomic makeup and phenotypic outcome. However, the majority of genetic studies have focused their attention on single candidate-gene mutations or on common variants reaching a significant statistical level of acceptance. This gene-centric approach is insufficient to uncover the genetic background of polygenic multifactorial disorders like PD, and potentially masks rare individual CNVs that all together might contribute to disease development or progression. In this review, we will discuss literature and bioinformatic data describing the involvement of CNVs on PD pathobiology. We will analyze the most frequent copy number changes in familiar PD genes and provide a "systems biology" overview of rare individual rearrangements that could functionally act on commonly deregulated molecular pathways. Assessing the global genome-wide burden of CNVs in PD patients may reveal new disease-related molecular mechanisms, and open the window to a new possible genetic scenario in the unsolved PD puzzle.

A customized high-resolution array-comparative genomic hybridization to explore copy number variations in Parkinson's disease.

Parkinson's disease (PD), the second most common progressive neurodegenerative disorder, was long believed to be a non-genetic sporadic syndrome. Today, only a small percentage of PD cases with genetic inheritance patterns are known, often complicated by reduced penetrance and variable expressivity. The few well-characterized Mendelian genes, together with a number of risk factors, contribute to the major sporadic forms of the disease, thus delineating an intricate genetic profile at the basis of this debilitating and incurable condition. Along with single nucleotide changes, gene-dosage abnormalities and copy number variations (CNVs) have emerged as significant disease-causing mutations in PD. However, due to their size variability and to the quantitative nature of the assay, CNV genotyping is particularly challenging. For this reason, innovative high-throughput platforms and bioinformatics algorithms are increasingly replacing classical CNV detection methods. Here, we report the design strategy, development, validation and implementation of NeuroArray, a customized exon-centric high-resolution array-based comparative genomic hybridization (aCGH) tailored to detect single/multi-exon deletions and duplications in a large panel of PD-related genes. This targeted design allows for a focused evaluation of structural imbalances in clinically relevant PD genes, combining exon-level resolution with genome-wide coverage. The NeuroArray platform may offer new insights in elucidating inherited potential or de novo structural alterations in PD patients and investigating new candidate genes.

Splicing: is there an alternative contribution to Parkinson's disease?

Alternative splicing is a crucial mechanism of gene expression regulation that enormously increases the coding potential of our genome and represents an intermediate step between messenger RNA (mRNA) transcription and protein posttranslational modifications. Alternative splicing occupies a central position in the development and functions of the nervous system. Therefore, its deregulation frequently leads to several neurological human disorders. In the present review, we provide an updated overview on the impact of alternative splicing in Parkinson's disease (PD), the second most common neurodegenerative disorder worldwide. We will describe the alternative splicing of major PD-linked genes by collecting the current evidences about this intricate and not carefully explored aspect. Assessing the role of this mechanism on PD pathobiology may represent a central step toward an improved understanding of this complex disease.

Increasing the Coding Potential of Genomes Through Alternative Splicing: The Case of PARK2 Gene.

The completion of the Human Genome Project aroused renewed interest in alternative splicing, an efficient and widespread mechanism that generates multiple protein isoforms from individual genes. Although our knowledge about alternative splicing is growing exponentially, its real impact on cellular life is still to be clarified. Connecting all splicing features (genes, splice transcripts, isoforms, and relative functions) may be useful to resolve this tangle. Herein, we will start from the case of a single gene, Parkinson protein 2, E3 ubiquitin protein ligase (PARK2), one of the largest in our genome. This gene is implicated in the pathogenesis of autosomal recessive juvenile Parkinsonism and it has been recently linked to cancer, leprosy, autism, type 2 diabetes mellitus and Alzheimer's disease. PARK2 primary transcript undergoes an extensive alternative splicing, which enhances transcriptomic diversification and protein diversity in tissues and cells. This review will provide an update of all human PARK2 alternative splice transcripts and isoforms presently known, and correlate them to those in rat and mouse, two common animal models for studying human disease genes. Alternative splicing relies upon a complex process that could be easily altered by both cis and trans-acting mutations. Although the contribution of PARK2 splicing in human disease remains to be fully explored, some evidences show disruption of this versatile form of genetic regulation may have pathological consequences.

The multifaceted role of the CXC chemokines and receptors signaling axes in ALS pathophysiology.

Amyotrophic lateral sclerosis (ALS) is a late-onset motor neuron disease with complex genetic basis and still no clear etiology. Multiple intertwined layers of immune system-related dysfunctions and neuroinflammatory mechanisms are emerging as substantial determinants in ALS onset and progression. In this review, we collect the increasingly arising evidence implicating four main CXC chemokines/cognate receptors signaling axes (CXCR1/2-CXCL1/2/8; CXCR3-CXCL9/10/11; CXCR4/7-CXCL12; CXCR5-CXCL13) in the pathophysiology of ALS. Findings in preclinical models implicate these signaling pathways in motor neuron toxicity and neuroprotection, while in ALS patients dysregulation of CXCLs/CXCRs has been shown at both central and peripheral levels. Immunological monitoring of CXC-ligands in ALS may allow tracking of disease progression, while pharmacological modulation of CXC-receptors provides a novel therapeutic strategy. A deeper understanding of the interplay between CXC-mediated neuroinflammation and ALS is crucial to advance research into treatments for this debilitating uncurable disorder.