Project description:Induced pluripotent stem cell-derived neurons from a sporadic Alzheimer disease donor as a model for investigating disease mechanisms
Project description:<p>Although clinical research has revealed microglia-related inflammatory and immune responses in bipolar disorder (BD) patient brains, it remains unclear how microglia contribute to the pathogenesis of BD. Here, we demonstrated that Serinc2 is associated with susceptibility to BD and showed a reduced expression in BDII patient plasma, which correlated with the disease severity. Using induced pluripotent stem cell (iPSC) models of sporadic and familial BDII patients, we found that Serinc2 expression showed deficits in iPSC-derived microglia-like cells, resulting in decreased synaptic pruning. Further, combining the microglia-specific Serinc2-deficient mouse and iPSC-microglia models, we found that microglial Serinc2 deficits functioned through attenuating the synthesis of serine-related phospholipids in the plasma membrane, thus resulting in depression-like behavioral abnormalities in the animals. Finally, we showed that the Serinc2-dependent lipid deficits diminished microglial membrane CR3 formation to interrupted synaptic pruning signals from neurons. Therefore, our results indicated that Serinc2 deficits in microglia might contribute to the pathogenesis of BD.</p>
Project description:Mitochondrial dysfunction plays a major role in the pathogenesis of sporadic Parkinson’s disease (PD) and familial PD caused by mutations in the PARK2 gene. The protein, parkin, is vital for mitochondrial function, but the lack of key PD phenotypes in PARK2 knockout (KO) rodent models has hindered investigations into parkin’s role in PD pathogenesis. Human isogenic induced pluripotent stem cell (iPSC) lines with and without PARK2 KO enable studies of the effect of parkin dysfunction in dopaminergic neuronal cultures.
Project description:Mitochondrial dysfunction plays a major role in the pathogenesis of sporadic Parkinson’s disease (PD) and familial PD caused by mutations in the PARK2 gene. The protein, parkin, is vital for mitochondrial function, but the lack of key PD phenotypes in PARK2 knockout (KO) rodent models has hindered investigations into parkin’s role in PD pathogenesis. Human isogenic induced pluripotent stem cell (iPSC) lines with and without PARK2 KO enable studies of the effect of parkin dysfunction in dopaminergic neuronal cultures.
Project description:Evidence suggests that extracellular vesicles (EVs) act as mediators and biomarkers of neurodegenerative diseases. Two distinct forms of Alzheimer Disease (AD) are known: a late-onset sporadic form (SAD) and an early-onset familial form (FAD). This project aims to characterize and compare the protein profile of systemic EVs from postmortem SAD and FAD patients and compared them to postmortem controls. We used LC-MS/MS label-free analysis.
Project description:Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease mainly affecting upper and lower motoneurons (MNs). In the last decades, several genes have been associated to the familial form of this disorder (fALS), thus depicting an extremely complex pathogenic landscape. The aim of this study was to identify convergent molecular underpinnings shared by ALS cases characterized by mutations in different genes using human induced pluripotent stem cells (hiPSCs).
Project description:Non-familial Alzheimer’s disease (AD) occurring before 65 years of age is commonly referred to as early-onset Alzheimer’s disease (EOAD) and constitutes ~5-6% of all Alzheimer’s disease (AD) cases. While EOAD exhibits the same clinicopathological changes such as amyloid plaques, neurofibrillary tangles (NFTs), brain atrophy, and cognitive decline as observed in the more prevalent late-onset AD (LOAD), EOAD patients tend to have more severe cognitive deficits, including visuospatial, language, and motor dysfunction. Patient-derived induced pluripotent stem cells (iPSCs) have been used to model and study penetrative, familial AD (FAD) mutations in APP, PSEN1, and PSEN2, but have been seldom used for sporadic forms of AD that display more heterogeneous disease manifestation. In this study, we sought to characterize iPSC-derived neurons from EOAD patients via RNA-sequencing. A modest difference in expression profiles between EOAD patients and non-demented control subjects resulted in a limited number of differentially expressed genes (DEGs). Based on this analysis, we provide evidence that iPSC-derived neuron model systems, likely due to the loss of EOAD-associated epigenetic signatures during the iPSC reprogramming, are not an ideal model system to study sporadic AD.
Project description:The discovery of cell-free micro-RNAs in body fluids has made them a promising biomarker target in the field of neurodegenerative diseases. Although they have been reported to be differentially expressed in biofluids and tissue from sporadic Parkinson’s disease patients, it remains unclear whether similar observations can be made in patients with genetic forms of the disease. Since induced pluripotent stem cell derived neurons represent a widely used research model for both sporadic and familial Parkinson’s disease, we sought to assess the usability of this model for the identification of differentially expressed cell-free micro-RNAs in the context of the Parkinson’s disease related LRRK2 G2019S mutation in a proof-of-concept study. We isolated extracellular vesicles carrying cell-free RNA from patient-derived induced pluripotent stem cell lines carrying the LRRK2 G2019S mutation and their gene corrected isogenic controls. After generation of small-RNA libraries and differential expression analysis, we validated fourteen micro-RNAs in an independent batch of cell-free and cellular RNA via RT-qPCR. Finally, we selected eleven differentially expressed micro-RNAs from our cell culture experiments and quantified their expression levels in cerebrospinal fluid derived from two LRRK2 G2019S patients and two healthy controls.