Progressive Neuronal Degeneration Research Articles

NPT100-18A rescues mitochondrial oxidative stress and neuronal degeneration in human iPSC-based Parkinson’s model

BackgroundParkinson’s disease (PD) is a neurodegenerative disorder characterized by protein aggregates mostly consisting of misfolded alpha-synuclein (αSyn). Progressive degeneration of midbrain dopaminergic neurons (mDANs) and nigrostriatal projections results in severe motor symptoms. While the preferential loss of mDANs has not been fully understood yet, the cell type-specific vulnerability has been linked to a unique intracellular milieu, influenced by dopamine metabolism, high demand for mitochondrial activity, and increased level of oxidative stress (OS). These factors have been shown to adversely impact αSyn aggregation. Reciprocally, αSyn aggregates, in particular oligomers, can impair mitochondrial functions and exacerbate OS. Recent drug-discovery studies have identified a series of small molecules, including NPT100-18A, which reduce αSyn oligomerization by preventing misfolding and dimerization. NPT100-18A and structurally similar compounds (such as NPT200-11/UCB0599, currently being assessed in clinical studies) point towards a promising new approach for disease-modification.MethodsInduced pluripotent stem cell (iPSC)-derived mDANs from PD patients with a monoallelic SNCA locus duplication and unaffected controls were treated with NPT100-18A. αSyn aggregation was evaluated biochemically and reactive oxygen species (ROS) levels were assessed in living mDANs using fluorescent dyes. Adenosine triphosphate (ATP) levels were measured using a luminescence-based assay, and neuronal cell death was evaluated by immunocytochemistry.ResultsCompared to controls, patient-derived mDANs exhibited higher cytoplasmic and mitochondrial ROS probe levels, reduced ATP-related signals, and increased activation of caspase-3, reflecting early neuronal cell death. NPT100-18A-treatment rescued cleaved caspase-3 levels to control levels and, importantly, attenuated mitochondrial oxidative stress probe levels in a compartment-specific manner and, at higher concentrations, increased ATP signals.ConclusionsOur findings demonstrate that NPT100-18A limits neuronal degeneration in a human in vitro model of PD. In addition, we provide first mechanistic insights into how a compartment-specific antioxidant effect in mitochondria might contribute to the neuroprotective effects of NPT100-18A.

Bifidobacterium infantis and Bifidobacterium breve Improve Symptomatology and Neuronal Damage in Neurodegenerative Disease: A Systematic Review

Background/Objectives: This systematic review focused on collecting the most significant findings on the impact of the administration of Bifidobacterium infantis (or Bifidobacterium longum subps. infantis) and Bifidobacterium breve, alone, in conjunction, or in combination with other strains, in the treatment of neurodegenerative diseases including Alzheimer’s disease (AD) and Parkinson’s disease (PD). These diseases are characterized by the progressive degeneration of neurons, resulting in a broad spectrum of clinical manifestations. AD is typified by a progressive decline in cognitive abilities, while PD is marked by motor symptoms associated with the loss of dopamine (DA). Methods: Five different databases, ScienceDirect, Scopus, Wiley, PubMed, and Web of Science (WoS), were reviewed and the studies were screened for inclusion by the following criteria: (i) studies that specifically evaluated the use of Bifidobacterium infantis, Bifidobacterium longum subsp. infantis, or Bifidobacterium breve as a therapeutic intervention, either in human or animal models, in the context of neurodegenerative diseases; (ii) the studies were required to address one or more of the pathologies examined in this article, and the pathologies included, but were not limited to, neurodegeneration, Alzheimer’s disease, Parkinson’s disease, and oxidative stress; (iii) the full text was accessible online; and (iv) the article was written in English. Results: The data suggest that these probiotics have neuroprotective effects that may delay disease progression. Conclusions: This study provides updated insights into the use of these Bifidobacterium strains in neurodegenerative diseases like AD and PD, with the main limitation being the limited number of clinical trials available.

High-prediction QSAR Modeling Study Based on the Efficacy of a Novel 6-hydroxybenzothiazole-2-carboxamide Targeted Monoamine Oxidase B in the Treatment of Neurodegenerative Diseases.

Neurodegenerative diseases are a group of disorders characterized by progressive neuronal degeneration and death, of which Alzheimer's disease and Parkinson's disease are the most common. These diseases are closely associated with increased expression of monoamine oxidase B (MAO-B), an important enzyme that regulates neurotransmitter concentration, and its overactivity leads to oxidative stress and neurotoxicity, accelerating the progression of neurodegenerative diseases. Therefore, the development of effective MAO-B inhibitors is important for the treatment of neurodegenerative diseases. This study aims to improve the prediction of the efficacy of novel 6-hydroxybenzothiazole- 2-carboxamide compounds in inhibiting MAO-B by improving the quantitative constitutive effect relationship (QSAR) modeling and to provide a theoretical basis for the discovery of novel neuroprotective drugs. The study first optimized the structures of 36 compounds using the heuristic method (HM) in CODESSA software to construct linear QSAR models. Subsequently, key descriptors were screened by using the gene expression programming (GEP) technique to generate nonlinear QSAR models and validate them. The R², F-value, and R²cv of the linear model were 0.5724, 10.3752, and 0.4557, respectively, whereas the nonlinear model constructed by the GEP algorithm showed higher prediction accuracies by achieving R² values of 0.89 and 0.82, and mean squared errors (MSE) of 0.0799 and 0.1215 for the training and test sets, respectively. In addition, molecular docking experiments confirmed that the novel compound 31 was tightly bound to the MAO-B active site with significant inhibitory activity. In this study, we successfully improved the prediction ability of the efficacy of novel 6-hydroxybenzothiazole-2-carboxamide compounds to inhibit MAO-B by improving the QSAR model. This not only provides new drug candidates for the treatment of neurodegenerative diseases, but also provides important theoretical guidance for subsequent drug design and development, which can help accelerate the process of new drug discovery and reduce the disease burden of patients.

Targeting the Interplay Between Autophagy and the Nrf2 Pathway in Parkinson's Disease with Potential Therapeutic Implications.

Parkinson's disease (PD) is a prevalent neurodegenerative disorder marked by the progressive degeneration of midbrain dopaminergic neurons and resultant locomotor dysfunction. Despite over two centuries of recognition as a chronic disease, the exact pathogenesis of PD remains elusive. The onset and progression of PD involve multiple complex pathological processes, with dysfunctional autophagy and elevated oxidative stress serving as critical contributors. Notably, emerging research has underscored the interplay between autophagy and oxidative stress in PD pathogenesis. Given the limited efficacy of therapies targeting either autophagy dysfunction or oxidative stress, it is crucial to elucidate the intricate mechanisms governing their interplay in PD to develop more effective therapeutics. This review overviews the role of autophagy and nuclear factor erythroid 2-related factor 2 (Nrf2), a pivotal transcriptional regulator orchestrating cellular defense mechanisms against oxidative stress, and the complex interplay between these processes. By elucidating the intricate interplay between these key pathological processes in PD, this review will deepen our comprehensive understanding of the multifaceted pathological processes underlying PD and may uncover potential strategies for its prevention and treatment.

Olfactory dysfunction as potential biomarker in neurodegenerative diseases: a narrative review.

Neurodegenerative diseases represent a group of disorders characterized by progressive degeneration of neurons in the central nervous system, leading to a range of cognitive, motor, and sensory impairments. In recent years, there has been growing interest in the association between neurodegenerative diseases and olfactory dysfunction (OD). Characterized by a decline in the ability to detect or identify odors, OD has been observed in various conditions, including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and Amyotrophic Lateral Sclerosis (ALS). This phenomenon often precedes the onset of other clinical symptoms, suggesting its potential utility as an early marker or prodromal symptom of neurodegenerative diseases. This review provides a vast literature overview on the current knowledge of OD in PD, AD, ALS, and HD in order to evaluate its potential as a biomarker, particularly in the early and prodromal stages of these diseases. We summarize the most common methods used to measure olfactory function and delve into neuropathological correlations and the alterations in neurotransmitter systems associated with OD in those neurodegenerative diseases, including differences in genetic variants if applicable, and cater to current pitfalls and shortcomings in the research.

Connectome-based biophysical models of pathological protein spreading in neurodegenerative diseases.

Neurodegenerative diseases are a group of disorders characterized by progressive degeneration or death of neurons. The complexity of clinical symptoms and irreversibility of disease progression significantly affects individual lives, leading to premature mortality. The prevalence of neurodegenerative diseases keeps increasing, yet the specific pathogenic mechanisms remain incompletely understood and effective treatment strategies are lacking. In recent years, convergent experimental evidence supports the "prion-like transmission" assumption that abnormal proteins induce misfolding of normal proteins, and these misfolded proteins propagate throughout the neural networks to cause neuronal death. To elucidate this dynamic process in vivo from a computational perspective, researchers have proposed three connectome-based biophysical models to simulate the spread of pathological proteins: the Network Diffusion Model, the Epidemic Spreading Model, and the agent-based Susceptible-Infectious-Removed model. These models have demonstrated promising predictive capabilities. This review focuses on the explanations of their fundamental principles and applications. Then, we compare the strengths and weaknesses of the models. Building upon this foundation, we introduce new directions for model optimization and propose a unified framework for the evaluation of connectome-based biophysical models. We expect that this review could lower the entry barrier for researchers in this field, accelerate model optimization, and thereby advance the clinical translation of connectome-based biophysical models.

The therapeutic effects of induced pluripotent stem cell‐derived mesenchymal stem cells on Parkinson's disease

AbstractParkinson's disease (PD), characterized by progressive degeneration of dopaminergic neurons in substantia nigra, has no disease‐modifying therapy. Mesenchymal stem cell (MSC) therapy has shown great promise as a disease‐modifying solution for PD. Induced pluripotent stem cell‐derived MSC (iMSC) not only has stronger neural repair function, but also helps solve the problem of MSC heterogeneity. So we evaluated the therapeutic effects of iMSCs on PD. iMSCs were administered by tail vein in 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine‐induced PD models of C57BL/6 mice. The results showed iMSCs increased body weights, inhibited the prolongation of latencies to descend in pole tests, the decrease of grip strength in grip strength tests and increase of open arm entries in elevated plus maze test, and showed a trend to alleviate striatal dopamine loss. They indicate iMSCs might improve functions partially by preserving striatal dopamine in PD. We for the first time (1) found that iMSC has therapeutic effects on PD; (2) tested specifically muscle strength in cell therapy for PD and found it increases muscle strength; (3) found cell therapy alleviated the increase of entries into the open arms in PD. It suggests iMSC is a promising candidate for clinical investigations and drug development for PD.

Care Pathway Heterogeneity in Amyotrophic Lateral Sclerosis: Effects of Gender, Age, and Onset

Background and Objectives: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive motor neuron degeneration resulting in loss of muscle function. Care management is restricted to symptomatic and palliative strategies, while clinical manifestations are heterogeneous. However, assessing the timing and benefits of ALS major clinical interventions remains challenging, with varying and nonspecific time-to-events estimates reported in the literature. Consequently, we proposed a retrospective cohort study leveraging healthcare system data to investigate ALS patients care pathway stratified by gender, age class, and onset site to describe strategies diversity and temporality. Methods: We developed an algorithm to identify incident ALS patients in the French hospitalization registry and assessed its quality through comparison with literature. We described 7 states, encompassing patient status regarding clinical intervention history, considered 15 transitions, and stratified the analysis depending on 12 different patient profiles, defined according to gender, the presence of symptoms indicative of disease onset site, and age class, to model profile-specific care pathway trajectories. Alongside analysis of median time before transition, we compared acceleration factors resulting from accelerated failure time and time-inhomogeneous models. Results: We identified 21,153 incident patients with ALS between 2013 and 2022 with a mean age of 67.7±13.1 years at time of in-registry detection, male/female and spinal/bulbar ratios of 1.2 and 1.9, respectively. Noninvasive ventilation (NIV), gastrostomy, tracheostomy, or death at hospital were recorded for 55.24% of the study population. We identified significant variations in utilization based on gender, age class, and onset site. Notably, older age and bulbar onset site accelerated gastrostomy use and spinal onset site was associated with delayed NIV initiation while tracheostomy, mainly considered for younger patients (<64 years), is rarely indicated in ALS care management. Alongside investigation of time-to-event speed, we report extensively the patient profile-specific estimated median delay before clinical event start. Conclusion: Leveraging real-world data from hospital registries provides a large sample size to investigate low prevalence diseases. In conjunction with multistate models, such data enable a comprehensive analysis of care pathways, which revealed variations in ALS management strategies based on patient profiles. By identifying these disparities, our study contributes to enhancing the foreseeability of support strategies for ALS patients.

Emerging role of Nrf2 in Parkinson's disease therapy: a critical reassessment.

Parkinson's disease (PD) is the neurodegenerative disorder characterized by the progressive degeneration of nigrostriatal dopaminergic neurons, leading to the range of motor and non-motor symptoms. There is mounting evidence suggesting that oxidative stress, neuroinflammation and mitochondrial dysfunction play pivotal roles in the pathogenesis of PD. Current therapies only alleviate perturbed motor symptoms. Therefore, it is essential to find out new therapies that allow us to improve not only motor symptoms, but non-motor symptoms like cognitive impairment and modulate disease progression. Nuclear factor erythroid 2-related factor 2 (Nrf2) is transcription factor that regulates the expression of numerous anti-oxidants and cytoprotective genes can counteract oxidative stress, neuroinflammation and mitochondrial dysfunction, thereby potentially ameliorating PD-associated pathology. The current review discusses about the Nrf2 structure and function with special emphasis on various molecular signalling pathways involved in positive and negative modulation of Nrf2, namely Glycogen synthase kinase-3β, Phosphoinositide-3-kinase, AMP-activated protein kinase, Mitogen activated protein kinase, nuclear factor-κB and P62. Furthermore, this review highlights the various Nrf2 activators as promising therapeutic agents for slowing down the progression of PD.

Exploring the Role of Axons in ALS from Multiple Perspectives.

Amyotrophic lateral sclerosis (ALS), commonly known as motor neuron disease, is a neurodegenerative disorder characterized by the progressive degeneration of both upper and lower motor neurons. This pathological process results in muscle weakness and can culminate in paralysis. To date, the precise etiology of ALS remains unclear. However, a burgeoning body of research indicates that axonal dysfunction is a pivotal element in the pathogenesis of ALS and significantly influences the progression of disease. Dysfunction of axons in ALS can result in impediments to nerve impulse transmission, leading to motor impairment, muscle atrophy, and other associated complications that severely compromise patients' quality of life and survival prognosis. In this review, we concentrate on several key areas: the ultrastructure of axons, the mechanisms of axonal degeneration in ALS, the impact of impaired axonal transport on disease progression in ALS, and the potential for axonal regeneration within the central nervous system (CNS). Our objective is to achieve a more holistic and profound understanding of the multifaceted role that axons play in ALS, thereby offering a more intricate and refined perspective on targeted axonal therapeutic interventions.

The Combined Use of Levodopa/Benserazide and Pramipexole Proves Beneficial for Managing Parkinson's Disease.

Parkinson's disease (PD), a prevalent neurological condition, is characterized by the progressive degeneration of dopamine-producing neurons, leading to motor dysfunction and non-motor symptoms. Therefore, this study aimed to evaluate the impact of combining levodopa/benserazide with pramipexole on PD patients, focusing on cognitive function, plasma monoamine neurotransmitter levels, and serum growth differentiation factor-15 (GDF-15) and angiopoietin-1 (Ang-1) levels. This retrospective study included 120 PD patients admitted to the hospital between January 2021 and January 2023. Based on the treatment approaches, the patients were categorized into the control group (n = 61) and the observation group (n = 59). The control group received oral levodopa/benserazide tablets, while the observation group was treated with levodopa/benserazide tablets combined with pramipexole. The two experimental groups were assessed and compared across several parameters, including PD symptoms [Unified Parkinson's Disease Rating Scale (UPDRS)], cognitive function [Montreal Cognitive Assessment (MoCA)], the levels of plasma monoamine neurotransmitters, and serum GDF-15 and Ang-1 levels. The response rate to treatment was more significant in the observation group (96.55%) compared to the control group (87.93%, p = 0.162). Post-treatment, both groups demonstrated a decline in their UPDRS and overall scores, with the observation group indicating substantially lower scores than the control group (p < 0.05). Furthermore, both groups showed improvements in MoCA scores, with the observation group exhibiting higher scores than the control group (p < 0.05). Similarly, we observed significantly increased dopamine, 5-hydroxytryptamine, and norepinephrine levels in both groups, with the observation group showing a more pronounced increase (p < 0.05). Additionally, we observed a significant decrease in serum GDF-15 levels and an increase in Ang-1 levels across both groups after treatment. However, the observation group exhibited lower GDF-15 levels and higher Ang-1 levels than the control group (p < 0.05). The combined use of levodopa/benserazide and pramipexole proves beneficial for managing PD. This therapeutic regimen can improve cognitive abilities and plasma monoamine neurotransmitter levels in PD patients, reduce brain tissue damage and decrease serum levels of GDF-15.

Neuroprotective effect of L-DOPA-induced interleukin-13 on striatonigral degeneration in cerebral ischemia

Levodopa (L-DOPA) treatment is a clinically effective strategy for improving motor function in patients with ischemic stroke. However, the mechanisms by which modulating the dopamine system relieves the pathology of the ischemic brain remain unclear. Emerging evidence from an experimental mouse model of ischemic stroke, established by middle cerebral artery occlusion (MCAO), suggested that L-DOPA has the potential to modulate the inflammatory and immune response that occurs during a stroke. Here, we aimed to demonstrate the therapeutic effect of L-DOPA in regulating the systemic immune response and improving functional deficits in mice with ischemia. Transient MCAO led to progressive degeneration of nigrostriatal dopamine neurons and significant rotational behavior in mice. Exogenous L-DOPA treatment attenuated the striatonigral degeneration and reversed motor behavioral impairment. Notably, treatment with L-DOPA significantly increased IL-13 but reduced IFN-γ in infarct lesions. To investigate the role of IL-13 in motor behavior, we stereotaxically injected anti-IL-13 antibodies into the infarct area of the mouse brain one week after MCAO, followed by L-DOPA treatment. The intervention reduced dopamine, IL-13, and IL-10 levels and exacerbated motor function. IL-13 is potentially expressed on CD4 T cells, while IL-10 is mainly expressed on microglia rather than astrocytes. Finally, IL-13 activates the phagocytosis of microglia, which may contribute to neuroprotection by eliminating degenerating neurons. Our study provides evidence that the L-DOPA-activated dopamine system modulates peripheral immune cells, resulting in the expression of anti-inflammatory and neuroprotective cytokines in mice with ischemic stroke.

Advances in drug screening and toxicity testing: A review on Parkinson's disease using brain-on-a-chip

Abstract. Neurodegenerative diseases like Parkinson's disease (PD) pose substantial challenges to health and well-being. PD is characterized by the progressive degeneration of dopamine-producing neurons in the substantia nigra of the brain, leading to motor dysfunction, cognitive decline, and various non-motor symptoms. Advances in drug screening and toxicity testing have transformed the study of neurodegenerative diseases. Traditional methods often fall short in replicating the intricate environment of the human brain, highlighting the necessity for alternative pre-clinical models. Brain-on-a-chip technology, an innovative in vitro platform, offers a promising solution by simulating the intricate architecture and microenvironment of brain tissue. This microfluidic device incorporates living brain cells within a controlled setting, enabling the examination of neuronal behavior, disorder mechanisms, and pharmacological responses in a physiologically relevant context. This review examines recent advancements in brain-on-a-chip systems for PD research, emphasizes their potential to advance drug discovery and toxicity testing, also discusses the difficulty and limitations of current brain-on-a-chip technologies, for examples, challenges of specific neuron cell selection and incubation, and also restriction of organ-organ connection. By comparing in vitro and in vivo studies, brain-on-a-chip technology shows great promise for accelerating the development of effective therapies for PD, ultimately contributing to improved patient outcomes and a deeper understanding of the disease.

Upregulated miR-10b-5p as a potential miRNA signature in amyotrophic lateral sclerosis patients.

Amyotrophic lateral sclerosis (ALS) is a fatal, adult-onset disease marked by a progressive degeneration of motor neurons (MNs) present in the spinal cord, brain stem and motor cortex. Death in most patients usually occurs within 2-4 years after symptoms onset. Despite promising progress in delineating underlying mechanisms, such as disturbed proteostasis, DNA/RNA metabolism, splicing or proper nucleocytoplasmic shuttling, there are no effective therapies for the vast majority of cases. A reason for this might be the disease heterogeneity and lack of substantial clinical and molecular biomarkers. The identification and validation of such pathophysiology driven biomarkers could be useful for early diagnosis and treatment stratification. Recent advances in next generation RNA-sequencing approaches have provided important insights to identify key changes of non-coding RNAs (ncRNAs) implicated with ALS disease. Especially, microRNAs (miRNAs) have emerged as key post-transcriptional regulators of gene expression to target several genes/pathways by degrading messenger RNAs (mRNAs) or repressing levels of gene expression. In this study, we expand our previous work to identify top-regulated differentially expressed (DE)-miRNAs by combining different normalizations to search for important and generalisable pathomechanistic dysregulations in ALS as putative novel biomarkers of the disease. For this we performed a consensus pipeline of existing datasets to investigate the transcriptomic profile (mRNAs and miRNAs) of MN cell lines from iPSC-derived SOD1- and TARDBP (TDP-43 protein)-mutant-ALS patients and healthy controls to identify potential signatures and their related pathways associated with neurodegeneration. Transcriptional profiling of miRNA-mRNA interactions from MN cell lines in ALS patients revealed differential expression of genes showed greater vulnerability to KEAP1-NRF2 stress response pathway, sharing a common molecular denominator linked to both disease conditions. We also reported that mutations in above genes led to significant upregulation of the top candidate miR-10b-5p, which we could validate in immortalized lymphoblast cell lines (LCLs) derived from sporadic and familial ALS patients and postmortem tissues of familial ALS patients. Collectively, our findings suggest that miRNA analysis simultaneously performed in various human biological samples may reveal shared miRNA profiles potentially useful as a biomarker of the disease.

Neuroprotective properties of zinc oxide nanoparticles: therapeutic implications for Parkinson's disease.

Parkinson's disease (PD) significantly affects millions of people worldwide due to the progressive degeneration of dopamine-producing neurons in the substantia nigra pars compacta. Despite extensive research efforts, effective treatments that can halt or reverse the progression of PD remain elusive. In recent years, nanotechnology has emerged as a promising new avenue for addressing this challenge, with zinc oxide nanoparticles (ZnO-NPs) standing out for their extensive therapeutic potential. ZnO-NPs have shown remarkable promise in neuroprotection through several key mechanisms. The multifaceted properties of ZnO-NPs suggest that they could play a crucial role in intervening across various fundamental mechanisms implicated in PD. By targeting these mechanisms, ZnO-NPs offer new insights and potential strategies for managing and treating PD. This review aims to provide a thorough examination of the molecular mechanisms through which ZnO-NPs exert their neuroprotective effects. It highlights their potential as innovative therapeutic agents for PD and outlines directions for future research to explore and harness their full capabilities.

Focusing on Enzyme Suppression in Neurodegenerative Disorders: Promising Approaches for Therapeutic Measures

: Neurodegenerative diseases, characterized by the progressive degeneration of neurons, represent a significant and growing global health concern. Despite extensive research, the underlying molecular mechanisms driving these conditions remain elusive. Enzyme dysregulation has emerged as a pivotal player in the pathogenesis of various neurodegenerative disorders, including Alzheimer's, Parkinson's, and Huntington's diseases. Understanding and targeting these enzymes hold immense therapeutic potential for mitigating disease progression. This abstract summarizes the current state of knowledge regarding the involvement of enzymes in neurodegenerative diseases and explores the potential therapeutic interventions aimed at enzyme inhibition. First, we provide an overview of the key enzymes implicated in each disorder and highlight their specific roles in neurodegenerative processes. Next, we delve into the intricate interplay between enzyme dysregulation and disease progression, elucidating the cascade of events leading to neuronal death and cognitive decline. Additionally, we explore promising preclinical and clinical studies that have shown encouraging results in inhibiting specific enzymes, validating the therapeutic potential of targeting these pathways. In conclusion, targeting enzyme inhibition in neurodegenerative diseases holds immense promise as a therapeutic avenue to slow disease progression and improve patients' quality of life. Nevertheless, considerable challenges lie ahead, necessitating collaborative efforts among researchers, clinicians, and pharmaceutical companies to develop safe, effective, and precise interventions for combating these devastating disorders. With continued advancements in molecular biology and drug discovery, we remain optimistic that the targeted modulation of enzymes will pave the way for innovative and transformative treatments in the realm of neurodegenerative diseases.

Cholesterol Accelerates Aggregation of α-Synuclein Simultaneously Increasing the Toxicity of Amyloid Fibrils.

A hallmark of Parkinson disease (PD) is a progressive degeneration of neurons in the substantia nigra pars compacta, hypothalamus, and thalamus. Although the exact etiology of irreversible neuronal degeneration is unclear, a growing body of experimental evidence indicates that PD could be triggered by the abrupt aggregation of α-synuclein (α-Syn), a small membrane protein that is responsible for cell vesicle trafficking. Phospholipids uniquely alter the rate of α-Syn aggregation and, consequently, change the cytotoxicity of α-Syn oligomers and fibrils. However, the role of cholesterol in the aggregation of α-Syn remains unclear. In this study, we used Caenorhabditis elegans that overexpressed α-Syn to investigate the effect of low (15%), normal (30%), and high (60%) concentrations of cholesterol on α-Syn aggregation. We found that an increase in the concentration of cholesterol in diets substantially shortened the lifespan of C. elegans. Using biophysical methods, we also investigated the extent to which large unilamellar vesicles (LUVs) with low, normal, and high concentrations of cholesterol altered the rate of α-Syn aggregation. We found that only lipid membranes with a 60% concentration of cholesterol substantially accelerated the rate of protein aggregation. Cell assays revealed that α-Syn fibrils formed in the presence of LUVs with different concentrations of cholesterol exerted very similar levels of cytotoxicity to rat dopaminergic neurons. These results suggest that changes in the concentration of cholesterol in the plasma membrane, which in turn could be caused by nutritional preferences, could accelerate the onset and progression of PD.

A Non-Invasive Gait-Based Screening Approach for Parkinson’s Disease

Parkinson's disease (PD) presents a significant global health challenge, characterized by the progressive degeneration of dopamine-producing neurons in the brain, resulting in both motor and non-motor symptoms that severely impact quality of life. This study addresses the complexities of PD, highlighting the critical need for early diagnosis to slow disease progression. This research addresses the challenges of early diagnosis, such as the use of unreliable diagnostic techniques and limited healthcare resources. It uses the MMU Parkinson Disease Dataset and applies camera-based data collection to analyze gait patterns that can identify a risk of Parkinson's Disease. The study utilizes computer vision and the AlphaPose framework to analyze video data and detect body key points. By employing machine learning algorithms, including Support Vector Machines (SVM) and CatBoost, showing highly effective in identifying temporal dependencies in gait patterns. The algorithms achieved a high accuracy of 83.33% on the MMU dataset. This method enhances the accuracy of PD detection and enables immediate detection and control of the disease. The combination of advanced data analysis methods and medical knowledge offers new possibilities to develop targeted treatments that improve patient outcomes, demonstrating the potential of machine learning in effectively managing and treating Parkinson's disease. To enhance the generalizability of models, future research should collect extensive and diverse datasets covering various backgrounds and different stages of Parkinson's disease and utilize advanced techniques for extracting features to improve the accuracy of gait analysis.

Enhanced Age-Dependent Motor Impairment in Males of Drosophila melanogaster Modeling Spinocerebellar Ataxia Type 1 Is Linked to Dysregulation of a Matrix Metalloproteinase.

Over the past two decades, Drosophila melanogaster has proven to be successful in modeling the polyglutamine (polyQ) (caused by CAG repeats) family of neurodegenerative disorders, including the faithful recapitulation of pathological features such as polyQ length-dependent formation of protein aggregates and progressive neuronal degeneration. In this study, pan-neuronal expression of human Ataxin-1 with long polyQ repeat of 82 amino acids was driven using an elav-GAL4 driver line. This would essentially model the polyQ disease spinocerebellar ataxia type 1 (SCA1). Longevity and behavioral analysis of male flies expressing human Ataxin-1 revealed compromised lifespan and accelerated locomotor activity deficits both in diurnal activity and negative geotaxis response compared to control flies. Interestingly, this decline in motor response was coupled to an enhancement of matrix metalloproteinase 1 (dMMP1) expression together with declining expression of extracellular matrix (ECM) fibroblast growth factor (FGF) signaling by hedgehog (Hh) and branchless (bnl) and a significant decrease in expression of survival motor neuron gene (dsmn) in old (30 d) flies. Taken together, our results indicate a role for dysregulation of matrix metalloproteinase in polyQ disease with consequent impact on ECM signaling factors, as well as SMN at the neuromuscular junction causing overt physiological and behavioral deficits.

A Review of Biomarkers of Amyotrophic Lateral Sclerosis: A Pathophysiologic Approach.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive degeneration of upper and lower motor neurons. The heterogeneous nature of ALS at the clinical, genetic, and pathological levels makes it challenging to develop diagnostic and prognostic tools that fit all disease phenotypes. Limitations associated with the functional scales and the qualitative nature of mainstay electrophysiological testing prompt the investigation of more objective quantitative assessment. Biofluid biomarkers have the potential to fill that gap by providing evidence of a disease process potentially early in the disease, its progression, and its response to therapy. In contrast to other neurodegenerative diseases, no biomarker has yet been validated in clinical use for ALS. Several fluid biomarkers have been investigated in clinical studies in ALS. Biofluid biomarkers reflect the different pathophysiological processes, from protein aggregation to muscle denervation. This review takes a pathophysiologic approach to summarizing the findings of clinical studies utilizing quantitative biofluid biomarkers in ALS, discusses the utility and shortcomings of each biomarker, and highlights the superiority of neurofilaments as biomarkers of neurodegeneration over other candidate biomarkers.