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Alzheimer's disease (AD) is a progressive, degenerative disorder that mainly results in memory loss and a cognitive disorder. Although the cause of AD is still unknown, a minor percentage of AD cases are produced by genetic mutations in the presenilin-1 (PSEN1) gene. Differentiated neuronal cells derived from induced pluripotent stem cells (iPSCs) of patients can recapitulate key pathological features of AD in vitro; however, iPSCs studies focused on the p.E280 A mutation, which afflicts the largest family in the world with familial AD, have not been carried out yet. Although a link between the loss of the Y (LOY) chromosome in peripheral blood cells and risk for AD has been reported, LOY-associated phenotype has not been previously studied in PSEN1 E280 A carriers. Here, we report the reprogramming of fibroblast cells into iPSCs from a familial AD patient with the PSEN1 E280 A mutation, followed by neuronal differentiation into neural precursor cells (NPCs), and the differentiation of NPCs into differentiated neurons that lacked a Y chromosome. Although the PSEN1 E280 A iPSCs and NPCs were successfully obtained, after 8 days of differentiation, PSEN1 E280 A differentiated neurons massively died reflected by release and/ or activation of death markers, and failed to reach complete neural differentiation compared to PSEN 1 wild type cells.

Parkinson's disease (PD) is a multifactorial, chronic, and progressive neurodegenerative disorder inducing movement alterations as a result of the loss of dopaminergic (DAergic) neurons of the pars compacta in the substantia nigra and protein aggregates of alpha synuclein (α-Syn). Although its etiopathology agent has not yet been clearly established, environmental and genetic factors have been suggested as the major contributors to the disease. Mutations in the glucosidase beta acid 1 (GBA1) gene, which encodes the lysosomal glucosylceramidase (GCase) enzyme, are one of the major genetic risks for PD. We found that the GBA1 K198E fibroblasts but not WT fibroblasts showed reduced catalytic activity of heterozygous mutant GCase by −70% but its expression levels increased by 3.68-fold; increased the acidification of autophagy vacuoles (e.g., autophagosomes, lysosomes, and autolysosomes) by +1600%; augmented the expression of autophagosome protein Beclin-1 (+133%) and LC3-II (+750%), and lysosomal–autophagosome fusion protein LAMP-2 (+107%); increased the accumulation of lysosomes (+400%); decreased the mitochondrial membrane potential (∆Ψm) by −19% but the expression of Parkin protein remained unperturbed; increased the oxidized DJ-1Cys106-SOH by +900%, as evidence of oxidative stress; increased phosphorylated LRRK2 at Ser935 (+1050%) along with phosphorylated α-synuclein (α-Syn) at pathological residue Ser129 (+1200%); increased the executer apoptotic protein caspase 3 (cleaved caspase 3) by +733%. Although exposure of WT fibroblasts to environmental neutoxin rotenone (ROT, 1 μM) exacerbated the autophagy–lysosomal system, oxidative stress, and apoptosis markers, ROT moderately increased those markers in GBA1 K198E fibroblasts. We concluded that the K198E mutation endogenously primes skin fibroblasts toward autophagy dysfunction, OS, and apoptosis. Our findings suggest that the GBA1 K198E fibroblasts are biochemically and molecularly equivalent to the response of WT GBA1 fibroblasts exposed to ROT. [ABSTRACT FROM AUTHOR]

Background: Familial Alzheimer's disease (FAD) is caused by mutations in one or more of 3 genes known as AβPP, PSEN1, and PSEN2. There are currently no effective therapies for FAD. Hence, novel therapeutics are needed. Objective: To analyze the effect of treatment with a combination of epigallocatechin-3-gallate (EGCG) and Melatonin (N-acetyl-5-methoxytryptamine, aMT) in a cerebral spheroid (CS) 3D in vitro model of PSEN 1 E280A FAD. Methods: We developed a CS in vitro model based on menstrual stromal cells derived from wild-type (WT) and mutant PSEN1 E280A menstrual blood cultured in Fast-N-Spheres V2 medium. Results: Beta-tubulin III, choline acetyltransferase, and GFAP in both WT and mutant CSs spontaneously expressed neuronal and astroglia markers when grown in Fast-N-Spheres V2 medium for 4 or 11 days. Mutant PSEN1 CSs had significantly increased levels of intracellular AβPP fragment peptides and concomitant appearance of oxidized DJ-1 as early as 4 days, and phosphorylated tau, decreased ΔΨm, and increased caspase-3 activity were observed on Day 11. Moreover, mutant CSs were unresponsive to acetylcholine. Treatment with a combination of EGCG and aMT decreased the levels of all typical pathological markers of FAD more efficiently than did EGCG or aMT alone, but aMT failed to restore Ca2+ influx in mutant CSs and decreased the beneficial effect of EGCG on Ca2+ influx in mutant CSs. Conclusion: Treatment with a combination of EGCG and aMT can be of high therapeutic value due to the high antioxidant capacity and anti-amyloidogenic effect of both compounds. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive memory loss and cognitive disturbance as a consequence of the loss of cholinergic neurons in the brain, neuritic plaques and hyperphosphorylation of TAU protein. Although the underlying mechanisms leading to these events are unclear, mutations in presenilin 1 (PSEN1), e.g., E280A (PSEN1 E280A), are causative factors for autosomal dominant early-onset familial AD (FAD). Despite advances in the understanding of the physiopathology of AD, there are no efficient therapies to date. Limitations in culturing brain-derived live neurons might explain the limited effectiveness of AD research. Here, we show that mesenchymal stromal (stem) cells (MSCs) can be used to model FAD, providing novel opportunities to study cellular mechanisms and to establish therapeutic strategies. Indeed, we cultured MSCs with the FAD mutation PSEN1 E280A and wild-type (WT) PSEN1 from umbilical cords and characterized the transdifferentiation of these cells into cholinergic-like neurons (ChLNs). PSEN1 E280A ChLNs but not WT PSEN1 ChLNs exhibited increased intracellular soluble amyloid precursor protein (sAPPf) fragments and extracellular Aβ42 peptide and TAU phosphorylation (at residues Ser202/Thr205), recapitulating the molecular pathogenesis of FAD caused by mutant PSEN1. Furthermore, PSEN1 E280A ChLNs presented oxidative stress (OS) as evidenced by the oxidation of DJ-1Cys106-SH into DJ-1Cys106-SO3 and the detection of DCF-positive cells and apoptosis markers such as activated pro-apoptosis proteins p53, c-JUN, PUMA and CASPASE-3 and the concomitant loss of the mitochondrial membrane potential and DNA fragmentation. Additionally, mutant ChLNs displayed Ca2+ flux dysregulation and deficient acetylcholinesterase (AChE) activity compared to control ChLNs. Interestingly, the inhibitor JNK SP600125 almost completely blocked TAU phosphorylation. Our findings demonstrate that FAD MSC-derived cholinergic neurons with the PSEN1 E280A mutation provide important clues for the identification of targetable pathological molecules. [ABSTRACT FROM AUTHOR]