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Induced pluripotent stem cells are shown to be useful for studying phenotypes relevant to familial and sporadic Alzheimer’s disease, even though it can take decades for the disease to manifest in patients. Alzheimer's disease in a dish Induced pluripotent stem (iPS) cell cultures are being used as models for various genetic diseases, including Parkinson's disease and diabetes. Alzheimer's disease seems an unlikely candidate for such a technique, because it can take decades for the disease to manifest in patients. But here, Lawrence Goldstein and colleagues provide evidence that iPS cell technology can be used to study phenotypes that are relevant to familial and sporadic Alzheimer's disease. Patient-derived fibroblasts were reprogrammed as iPS cells and differentiated into neurons expressing various biochemical markers of Alzheimer's disease, including elevated amyloid-β secretion. Treatment of neurons with a γ-secretase inhibitor, a type of drug considered a candidate for Alzheimer's therapy, significantly reduced both amyloid-β and phospho-tau levels. Our understanding of Alzheimer’s disease pathogenesis is currently limited by difficulties in obtaining live neurons from patients and the inability to model the sporadic form of the disease. It may be possible to overcome these challenges by reprogramming primary cells from patients into induced pluripotent stem cells (iPSCs). Here we reprogrammed primary fibroblasts from two patients with familial Alzheimer’s disease, both caused by a duplication of the amyloid-β precursor protein gene 1 ( APP ; termed APP Dp ), two with sporadic Alzheimer’s disease (termed sAD1, sAD2) and two non-demented control individuals into iPSC lines. Neurons from differentiated cultures were purified with fluorescence-activated cell sorting and characterized. Purified cultures contained more than 90% neurons, clustered with fetal brain messenger RNA samples by microarray criteria, and could form functional synaptic contacts. Virtually all cells exhibited normal electrophysiological activity. Relative to controls, iPSC-derived, purified neurons from the two APP Dp patients and patient sAD2 exhibited significantly higher levels of the pathological markers amyloid-β(1–40), phospho-tau(Thr 231) and active glycogen synthase kinase-3β (aGSK-3β). Neurons from APP Dp and sAD2 patients also accumulated large RAB5-positive early endosomes compared to controls. Treatment of purified neurons with β-secretase inhibitors, but not γ-secretase inhibitors, caused significant reductions in phospho-Tau(Thr 231) and aGSK-3β levels. These results suggest a direct relationship between APP proteolytic processing, but not amyloid-β, in GSK-3β activation and tau phosphorylation in human neurons. Additionally, we observed that neurons with the genome of one sAD patient exhibited the phenotypes seen in familial Alzheimer’s disease samples. More generally, we demonstrate that iPSC technology can be used to observe phenotypes relevant to Alzheimer’s disease, even though it can take decades for overt disease to manifest in patients.

Neural induction of human pluripotent stem cells often yields heterogeneous cell populations that can hamper quantitative and comparative analyses. There is a need for improved differentiation and enrichment procedures that generate highly pure populations of neural stem cells (NSC), glia and neurons. One way to address this problem is to identify cell-surface signatures that enable the isolation of these cell types from heterogeneous cell populations by fluorescence activated cell sorting (FACS). We performed an unbiased FACS- and image-based immunophenotyping analysis using 190 antibodies to cell surface markers on naïve human embryonic stem cells (hESC) and cell derivatives from neural differentiation cultures. From this analysis we identified prospective cell surface signatures for the isolation of NSC, glia and neurons. We isolated a population of NSC that was CD184(+)/CD271(-)/CD44(-)/CD24(+) from neural induction cultures of hESC and human induced pluripotent stem cells (hiPSC). Sorted NSC could be propagated for many passages and could differentiate to mixed cultures of neurons and glia in vitro and in vivo. A population of neurons that was CD184(-)/CD44(-)/CD15(LOW)/CD24(+) and a population of glia that was CD184(+)/CD44(+) were subsequently purified from cultures of differentiating NSC. Purified neurons were viable, expressed mature and subtype-specific neuronal markers, and could fire action potentials. Purified glia were mitotic and could mature to GFAP-expressing astrocytes in vitro and in vivo. These findings illustrate the utility of immunophenotyping screens for the identification of cell surface signatures of neural cells derived from human pluripotent stem cells. These signatures can be used for isolating highly pure populations of viable NSC, glia and neurons by FACS. The methods described here will enable downstream studies that require consistent and defined neural cell populations.

The use of genetic engineering to generate point mutations in induced pluripotent stem cells (iPSCs) is essential for studying a specific genetic effect in an isogenic background. We demonstrate that a combination of p53 inhibition and pro-survival small molecules achieves a homologous recombination rate higher than 90% using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) in human iPSCs. Our protocol reduces the effort and time required to create isogenic lines.

We report the cloning and characterization of TOX3, a high mobility group box protein involved in mediating calcium-dependent transcription. TOX3 was identified as a calcium-dependent transactivator using the Transactivator Trap screen. We find that TOX3 interacts with both cAMP response element (CRE)-binding protein (CREB) and CREB-binding protein (CBP), and knockdown of the endogenous TOX3 by RNAi leads to significant reduction of calcium-induced c-fos expression and complete inhibition of calcium activation of the c-fos promoter. The effects of TOX3 on calcium-dependent transcription require the CRE elements. These observations identify TOX3 as an important regulator of calcium-dependent transcription and suggest that TOX3 exerts its effect on CRE-mediated transcription via its association with the CREB-CBP complex.

Alzheimer's Disease (AD) constitutes a major societal problem with devastating neuropsychiatric involvement in over 90% of those diagnosed. The large spectrum of AD neuropsychiatric symptoms leads to polypharmacological prescribing that, in turn, poses a major risk for increased side effects. Non-pharmacological interventions such as music therapy (MT) are therefore recommended as first-line treatments. The amalgamation of an aging population, long lifespan, and shortage of qualified music therapists limits access to MT services for AD. The purpose of this paper is to provide a rationale for a protocolized music teletherapy (MTT) intervention to increase accessibility for MT as a psychosocial intervention for neuropsychiatric symptoms in people with AD by conducting a narrative review of the existing MT and AD literature. We conducted a narrative review of MT and MTT publications indexed in PubMed and Google Scholar wherein authors used the Neuropsychiatric Inventory. We examined the impact of MT on neuropsychiatric symptoms of AD and identified MTT as a way to increase access to clinical services. MT can have positive impacts on neuropsychiatric symptoms in AD. However, we identified an ensuing need for protocolized MT interventions, access to services, and increased awareness. MTT is an option that can address these needs. Although MT can have positive effects on neuropsychiatric symptoms and can be beneficial and safe for individuals with AD, the current approach to MT practice is enormously heterogeneous with studies demonstrating variable therapist qualifications, uses of music, therapy approaches, and clinical populations. Congruently, the existing literature indicates that MT has not been standardized with protocolized interventions, making it difficult for clinicians and researchers to objectively assess the evidence, and thus, prescribe MT interventions. The lack of MT standardization, coupled with a low number of music therapists relative to people with AD, result in a lack of awareness that hinders access to MT as a psychosocial treatment for neuropsychiatric symptoms in people with AD. We therefore propose that protocolized MTT interventions are needed to increase access to better address neuropsychiatric symptoms associated with AD.

Neurodegenerative diseases are an ever-increasing problem for the rapidly aging population. Despite this, our understanding of how these neurodegenerative diseases develop and progress, is in most cases, rudimentary. Protein kinase RNA (PKR)-like ER kinase (PERK) comprises one of three unfolded protein response pathways in which cells attempt to manage cellular stress. However, because of its role in the cellular stress response and the far-reaching implications of this pathway, error within the PERK pathway has been shown to lead to a variety of pathologies. Genetic and clinical studies show a correlation between failure of the PERK pathway in neural cells and the development of neurodegeneration, but the wide array of methodology of these studies is presenting conflicting narratives about the role of PERK in these affected systems. Because of the connection between PERK and pathology, PERK has become a high value target of study for understanding neurodegenerative diseases and potentially how to treat them. Here, we present a review of the literature indexed in PubMed of the PERK pathway and some of the complexities involved in investigating the protein’s role in the development of neurodegenerative diseases as well as how it may act as a target for therapeutics.

Chronic traumatic encephalopathy (CTE) has been receiving increasing attention due to press coverage of professional football players. The devastating sequelae of CTE compel us to aim for early diagnosis and treatment. However, by current standards, CTE is challenging to diagnose. Clear clinical diagnostic criteria for CTE have not been established. Only recently, pathological diagnostic criteria have been recognized, but postmortem diagnosis is too late. Reliable biomarkers are not available. By imaging criteria, cavum septum pellucidum has been the only consistent identifiable MRI finding. Because of the imprecise nature of diagnosis based on clinical suspicion, physicians must become cognizant of the broad spectrum of presentations of CTE. With this awareness, appropriate workup can be initiated. CTE can present with early symptoms of emotional changes or late symptoms with memory decline and dementia. Here we present an unusual case of a patient with Alzheimer’s disease secondary to suspected CTE that stems from subconcussive head impacts presenting with severe memory and MRI changes. Clinicians should be aware of this presentation and consider CTE in their differential diagnoses while undergoing workup of memory disorders.

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease caused by head trauma. Diagnosis of this disease is difficult as reliable biomarkers have not been established and often this clinical entity is underappreciated with poor recognition of its clinical presentations (Lenihan and Jordan, 2015). The definitive diagnosis of CTE is determined by identification of neurofibrillary tangles in the perivascular space around the sulci in postmortem tissue (McKee et al., 2015). However, performing brain biopsies searching for neurofibrillary tangles is not a feasible option for early diagnosis. Thus, diagnosis of suspected CTE in the living has been based on clinical suspicion using proposed research criteria of clinical presentations. In addition, neuroimaging techniques have shown some promise in assisting diagnosis. Clinically, CTE is more commonly known to be associated with memory impairment and executive function disorder (Stern et al., 2013). However, here, we present two unique cases of prior professional football players where behavioral changes were the first identifying factors in clinical presentation and discuss possible neuroimaging options to help with CTE diagnosis. Because behavioral changes can be mistaken for other neuropsychological diseases, recognizing differing clinical constellations is critical to early diagnosis, early intervention, and improving patient care in suspected CTE.

The extracellular matrix (ECM) plays important roles in influencing cellular behavior such as attachment, differentiation, and proliferation. However, in conventional culture and tissue engineering strategies, single proteins are frequently utilized, which do not mimic the complex extracellular microenvironment seen in vivo. In this study we report a method to decellularize brain tissue using detergents. This decellularized brain matrix is rich in glycosaminoglycans and contains collagen I, collagen III, collagen IV, collagen V, collagen VI, perlecan, and laminin. By further processing the material into a liquid form, the brain matrix can be used as a cell culture coating. Neurons derived from human induced pluripotent stem cells plated on the brain matrix express neuronal markers and assume neuronal morphology. Additionally, the same material can potentially be used as a scaffold for tissue engineering as it reassembles upon injection in vivo to form a gel. Thus, our work demonstrates the ability to use decellularized brain ECM for cell culture and tissue engineering applications.