Alpha-Synuclein Gene Alterations Modulate Tyrosine Hydroxylase in Human iPSC-Derived Neurons in a Parkinson's Disease Animal Model.

Parkinson's disease (PD) caused by gene triplication (3X) leads to early onset, rapid progression, and often dementia. Understanding the impact of 3X and its absence is crucial. This study investigates the differentiation of human induced pluripotent stem cell (hiPSC)-derived floor-plate progenitors into dopaminergic neurons.

Identification and validation of N-acetylputrescine in combination with non-canonical clinical features as a Parkinson's disease biomarker panel.

Parkinson's disease is a progressive neurodegenerative disorder in which loss of dopaminergic neurons in the substantia nigra results in a clinically heterogeneous group with variable motor and non-motor symptoms with a degree of misdiagnosis. Only 3-25% of sporadic Parkinson's patients present with genetic abnormalities that could represent a risk factor, thus environmental, metabolic, and other unknown causes contribute to the pathogenesis of Parkinson's disease, which highlights the critical need for biomarkers. In the present study, we prospectively collected and analyzed plasma samples from 194 Parkinson's disease patients and 197 age-matched non-diseased controls.

Inactive S. aureus Cas9 downregulates alpha-synuclein and reduces mtDNA damage and oxidative stress levels in human stem cell model of Parkinson's disease.

Parkinson's disease (PD) is one of the most common neurodegenerative diseases, but no disease modifying therapies have been successful in clinical translation presenting a major unmet medical need. A promising target is alpha-synuclein or its aggregated form, which accumulates in the brain of PD patients as Lewy bodies. While it is not entirely clear which alpha-synuclein protein species is disease relevant, mere overexpression of alpha-synuclein in hereditary forms leads to neurodegeneration.

Automated 384-well SYBR Green Expression Array for Optimization of Human Induced Pluripotent Stem Cell Differentiation.

Cell populations and tissues exhibit unique gene expression profiles, which allow for characterizing and distinguishing cellular subtypes. Monitoring gene expression of cell type-specific markers can indicate cell status such as proliferation, stress, quiescence, or maturation. Quantitative reverse transcriptase PCR (qRT-PCR) allows quantifying RNA expression of cell type-specific markers and distinguishing one cell type from another.

Embryoid Body Cells from Human Embryonic Stem Cells Overexpressing Dopaminergic Transcription Factors Survive and Initiate Neurogenesis via Neural Rosettes in the Substantia Nigra.

Transplantation of immature dopaminergic neurons or neural precursors derived from embryonic stem cells (ESCs) into the substantia nigra pars compacta (SNpc) is a potential therapeutic approach for functional restitution of the nigrostriatal pathway in Parkinson's disease (PD). However, further studies are needed to understand the effects of the local microenvironment on the transplanted cells to improve survival and specific differentiation in situ. We have previously reported that the adult SNpc sustains a neurogenic microenvironment.

Nuclease-dead S. Cas9 downregulates alpha-synuclein and reduces mtDNA damage and oxidative stress levels in patient-derived stem cell model of Parkinson's disease.

Parkinson's disease (PD) is one of the most common neurodegenerative diseases, but no disease modifying therapies have been successful in clinical translation presenting a major unmet medical need. A promising target is alpha-synuclein or its aggregated form, which accumulates in the brain of PD patients as Lewy bodies. While it is not entirely clear which alpha-synuclein protein species is disease relevant, mere overexpression of alpha-synuclein in hereditary forms leads to neurodegeneration.

A reference human induced pluripotent stem cell line for large-scale collaborative studies.

Human induced pluripotent stem cell (iPSC) lines are a powerful tool for studying development and disease, but the considerable phenotypic variation between lines makes it challenging to replicate key findings and integrate data across research groups. To address this issue, we sub-cloned candidate human iPSC lines and deeply characterized their genetic properties using whole genome sequencing, their genomic stability upon CRISPR-Cas9-based gene editing, and their phenotypic properties including differentiation to commonly used cell types. These studies identified KOLF2.

Early embryonic lethality in complex I associated p.L104P Nubpl mutant mice.

Background: Variants in the mitochondrial complex I assembly factor, NUBPL are associated with a rare cause of complex I deficiency mitochondrial disease. Patients affected by complex I deficiency harboring homozygous NUBPL variants typically have neurological problems including seizures, intellectual disability, and ataxia associated with cerebellar hypoplasia. Thus far only 19 cases have been reported worldwide, and no treatment is available for this rare disease.

ATTCT and ATTCC repeat expansions in the ATXN10 gene affect disease penetrance of spinocerebellar ataxia type 10.

Spinocerebellar ataxia type 10 (SCA10) is an autosomal-dominant disorder caused by an expanded pentanucleotide repeat in the gene. This repeat expansion, when fully penetrant, has a size of 850-4,500 repeats. It has been shown that the repeat composition can be a modifier of disease, e.

Gene Expression Analysis in Stem Cell-derived Cortical Neuronal Cultures Using Multi-well SYBR Green Quantitative PCR Arrays.

To optimize differentiation protocols for stem cell-based modeling applications, it is essential to assess the change in gene expression during the differentiation process. This allows controlling its differentiation efficiency into the target cell types. While RNA transcriptomics provides detail at a larger scale, timing and cost are prohibitive to include such analyses in the optimization process.

Multiplex imaging of human induced pluripotent stem cell-derived neurons with CO-Detection by indEXing (CODEX) technology.

Background: Human induced pluripotent stem cell (iPSC) models have been hailed as a breakthrough for understanding disease and developing new therapeutics. The major advantage of iPSC-derived neurons is that they carry the genetic background of the donor, and as such could be more predictive for clinical translation. However, the development of these cell models is time-consuming and expensive and it is thus critical to maximize readout of markers for immunocytochemistry.

Effect of LRRK2 protein and activity on stimulated cytokines in human monocytes and macrophages.

Leucine-rich-repeat kinase 2 (LRRK2), a potential therapeutic target for the treatment of Parkinson's disease (PD), is highly expressed in monocytes and macrophages and may play a role in the regulation of inflammatory pathways. To determine how LRRK2 protein levels and/or its activity modulate inflammatory cytokine/chemokine levels in human immune cells, isogenic human induced pluripotent stem cells (iPSC) with the LRRK2-activating G2019S mutation, wild-type LRRK2, and iPSC deficient in LRRK2 were differentiated to monocytes and macrophages and stimulated with inflammatory toll-like receptor (TLR) agonists in the presence and absence of LRRK2 kinase inhibitors. The effect of LRRK2 inhibitors and the effect of increasing LRRK2 levels with interferon gamma on TLR-stimulated cytokines were also assessed in primary peripheral blood-derived monocytes.

Isogenic human SNCA gene dosage induced pluripotent stem cells to model Parkinson's disease.

Alpha-synuclein overexpression and aggregation are critical factors in the pathogenesis of Parkinson's disease (PD). Clinical cases with alpha-synuclein (SNCA) multiplications or deletions indicate that gene expression levels are essential for neurodegeneration and neurodevelopment. Here, we developed an isogenic SNCA gene dosage model using CRISPR/Cas9 gene editing to introduce frameshift mutations into exon 2 of the SNCA coding region in human induced pluripotent stem cells (iPSCs) from a patient with an SNCA triplication.

Phenotypic Heterogeneity among p.R202X Carriers in Lewy Body Spectrum Disorders.

We describe the clinical and neuropathologic features of patients with Lewy body spectrum disorder (LBSD) carrying a nonsense variant, c.604C>T; p.R202X, in the glucocerebrosidase 1 () gene.

Embryoid Body Formation from Mouse and Human Pluripotent Stem Cells for Transplantation to Study Brain Microenvironment and Cellular Differentiation.

Human embryonic stem cell (hESC) and human-induced pluripotent stem cell (hiPSC) technologies have a critical role in regenerative strategies for personalized medicine. Both share the ability to differentiate into almost any cell type of the human body. The study of their properties and clinical applications requires the development of robust and reproducible cell culture paradigms that direct cell differentiation toward a specific phenotype in vitro and in vivo.

Short-term deceleration capacity of heart rate: a sensitive marker of cardiac autonomic dysfunction in idiopathic Parkinson's disease.

Purpose: Cardiac autonomic dysfunction in idiopathic Parkinson's disease (PD) manifests as reduced heart rate variability (HRV). In the present study, we explored the deceleration capacity of heart rate (DC) in patients with idiopathic PD, an advanced HRV marker that has proven clinical utility.

Methods: Standard and advanced HRV measures derived from 7-min electrocardiograms in 20 idiopathic PD patients and 27 healthy controls were analyzed.

Genomewide Association Studies of LRRK2 Modifiers of Parkinson's Disease.

Objective: The aim of this study was to search for genes/variants that modify the effect of LRRK2 mutations in terms of penetrance and age-at-onset of Parkinson's disease.

Methods: We performed the first genomewide association study of penetrance and age-at-onset of Parkinson's disease in LRRK2 mutation carriers (776 cases and 1,103 non-cases at their last evaluation). Cox proportional hazard models and linear mixed models were used to identify modifiers of penetrance and age-at-onset of LRRK2 mutations, respectively.

Genetic and Environmental Factors Influence the Pleomorphy of Parkinsonism.

Missense mutations in the gene were first identified as a pathogenic cause of Parkinson's disease (PD) in 2004. Soon thereafter, a founder mutation in , p.G2019S (rs34637584), was described, and it is now estimated that there are approximately 100,000 people worldwide carrying this risk variant.

Loss-of-Function Mutation May Link Parkinson's Disease to Recessive Complex I Deficiency.

In an unbiased genome-wide screen for copy number variants (CNVs) on a cohort of Parkinson's disease (PD) patients, we identified in one patient a complex chromosomal rearrangement involving the nucleotide binding protein-like () gene on chromosome 14q12. We noted that mutations in the gene had been reported as causing autosomal recessive (AR) mitochondrial Complex I (CI) deficiency in children. The precise breakpoints of the rearrangement in our PD case were found to be identical to those described in a patient with AR CI deficiency who also harbored a second pathogenic mutation in .

The Role of Alpha-Synuclein and Other Parkinson's Genes in Neurodevelopmental and Neurodegenerative Disorders.

Neurodevelopmental and late-onset neurodegenerative disorders present as separate entities that are clinically and neuropathologically quite distinct. However, recent evidence has highlighted surprising commonalities and converging features at the clinical, genomic, and molecular level between these two disease spectra. This is particularly striking in the context of autism spectrum disorder (ASD) and Parkinson's disease (PD).

Nonsteroidal Anti-inflammatory Use and LRRK2 Parkinson's Disease Penetrance.

Background: The penetrance of leucine rich repeat kinase 2 (LRRK2) mutations is incomplete and may be influenced by environmental and/or other genetic factors. Nonsteroidal anti-inflammatory drugs (NSAIDs) are known to reduce inflammation and may lower Parkinson's disease (PD) risk, but their role in LRRK2-associated PD is unknown.

Objectives: The objective of this study is to evaluate the association of regular NSAID use and LRRK2-associated PD.

Correction: Pulse-Field capillary electrophoresis of repeat-primed PCR amplicons for analysis of large repeats in Spinocerebellar Ataxia Type 10.

[This corrects the article DOI: 10.1371/journal.pone.

Alpha-Synuclein Physiology and Pathology: A Perspective on Cellular Structures and Organelles.

Alpha-synuclein (α-syn) is localized in cellular organelles of most neurons, but many of its physiological functions are only partially understood. α-syn accumulation is associated with Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy as well as other synucleinopathies; however, the exact pathomechanisms that underlie these neurodegenerative diseases remain elusive. In this review, we describe what is known about α-syn function and pathophysiological changes in different cellular structures and organelles, including what is known about its behavior as a prion-like protein.

Report of the Phenotype of a Patient with Roberts Syndrome and a Rare Variant.

Roberts syndrome is a rare autosomal recessive genetic disease. In this report, we report a Brazilian patient with a rare variant. The patient manifested a broad range of clinical findings including the significant, bilateral shortening of the extremities.

Exosome/microvesicle content is altered in leucine-rich repeat kinase 2 mutant induced pluripotent stem cell-derived neural cells.

Extracellular vesicles, including exosomes/microvesicles (EMVs), have been described as sensitive biomarkers that represent disease states and response to therapies. In light of recent reports of disease-mirroring EMV molecular signatures, the present study profiled two EMVs from different Parkinson's disease (PD) tissue sources: (a) neural progenitor cells derived from an endogenous adult stem/progenitor cell, called adult human neural progenitor (AHNP) cells, that we found to be pathological when isolated from postmortem PD patients' substantia nigra; and (b) leucine-rich repeat kinase 2 (LRRK2) gene identified patient induced pluripotent stem cells (iPSCs), which were used to isolate EMVs and begin to characterize their cargoes. Initial characterization of EMVs derived from idiopathic patients (AHNPs) and mutant LRRK2 patients showed differences between both phenotypes and when compared with a sibling control in EMV size and release based on Nanosight analysis.