β-Amyloid 1-42 Oligomers Impair Function of Human Embryonic Stem Cell-Derived Forebrain Cholinergic Neurons

Cognitive impairment in Alzheimer's disease (AD) patients is associated with a decline in the levels of growth factors, impairment of axonal transport and marked degeneration of basal forebrain cholinergic neurons (BFCNs). Neurogenesis persists in the adult human brain, and the stimulation of regenerative processes in the CNS is an attractive prospect for neuroreplacement therapy in neurodegenerative diseases such as AD. Currently, it is still not clear how the pathophysiological environment in the AD brain affects stem cell biology. Previous studies investigating the effects of the β-amyloid (Aβ) peptide on neurogenesis have been inconclusive, since both neurogenic and neurotoxic effects on progenitor cell populations have been reported. In this study, we treated pluripotent human embryonic stem (hES) cells with nerve growth factor (NGF) as well as with fibrillar and oligomeric Aβ1-40 and Aβ1-42 (nM-µM concentrations) and thereafter studied the differentiation in vitro during 28-35 days. The process applied real time quantitative PCR, immunocytochemistry as well as functional studies of intracellular calcium signaling. Treatment with NGF promoted the differentiation into functionally mature BFCNs. In comparison to untreated cells, oligomeric Aβ1–40 increased the number of functional neurons, whereas oligomeric Aβ1–42 suppressed the number of functional neurons. Interestingly, oligomeric Aβ exposure did not influence the number of hES cell-derived neurons compared with untreated cells, while in contrast fibrillar Aβ1–40 and Aβ1–42 induced gliogenesis. These findings indicate that Aβ1–42 oligomers may impair the function of stem cell-derived neurons. We propose that it may be possible for future AD therapies to promote the maturation of functional stem cell-derived neurons by altering the brain microenvironment with trophic support and by targeting different aggregation forms of Aβ

Intranasal “painless” Human Nerve Growth Factors Slows Amyloid Neurodegeneration and Prevents Memory Deficits in App X PS1 Mice

Nerve Growth Factor (NGF) is being considered as a therapeutic candidate for Alzheimer's disease (AD) treatment but the clinical application is hindered by its potent pro-nociceptive activity. Thus, to reduce systemic exposure that would induce pain, in recent clinical studies NGF was administered through an invasive intracerebral gene-therapy approach. Our group demonstrated the feasibility of a non-invasive intranasal delivery of NGF in a mouse model of neurodegeneration. NGF therapeutic window could be further increased if its nociceptive effects could be avoided altogether. In this study we exploit forms of NGF, mutated at residue R100, inspired by the human genetic disease HSAN V (Hereditary Sensory Autonomic Neuropathy Type V), which would allow increasing the dose of NGF without triggering pain. We show that “painless” hNGF displays full neurotrophic and anti-amyloidogenic activities in neuronal cultures, and a reduced nociceptive activity in vivo. When administered intranasally to APPxPS1 mice ( n = 8), hNGFP61S/R100E prevents the progress of neurodegeneration and of behavioral deficits. These results demonstrate the in vivo neuroprotective and anti-amyloidogenic properties of hNGFR100 mutants and provide a rational basis for the development of “painless” hNGF variants as a new generation of therapeutics for neurodegenerative diseases

Cellular therapies for treating pain associated with spinal cord injury

Spinal cord injury leads to immense disability and loss of quality of life in human with no satisfactory clinical cure. Cell-based or cell-related therapies have emerged as promising therapeutic potentials both in regeneration of spinal cord and mitigation of neuropathic pain due to spinal cord injury. This article reviews the various options and their latest developments with an update on their therapeutic potentials and clinical trialing

The modular systems biology approach to investigate the control of apoptosis in Alzheimer's disease neurodegeneration

Apoptosis is a programmed cell death that plays a critical role during the development of the nervous system and in many chronic neurodegenerative diseases, including Alzheimer's disease (AD). This pathology, characterized by a progressive degeneration of cholinergic function resulting in a remarkable cognitive decline, is the most common form of dementia with high social and economic impact. Current therapies of AD are only symptomatic, therefore the need to elucidate the mechanisms underlying the onset and progression of the disease is surely needed in order to develop effective pharmacological therapies. Because of its pivotal role in neuronal cell death, apoptosis has been considered one of the most appealing therapeutic targets, however, due to the complexity of the molecular mechanisms involving the various triggering events and the many signaling cascades leading to cell death, a comprehensive understanding of this process is still lacking. Modular systems biology is a very effective strategy in organizing information about complex biological processes and deriving modular and mathematical models that greatly simplify the identification of key steps of a given process. This review aims at describing the main steps underlying the strategy of modular systems biology and briefly summarizes how this approach has been successfully applied for cell cycle studies. Moreover, after giving an overview of the many molecular mechanisms underlying apoptosis in AD, we present both a modular and a molecular model of neuronal apoptosis that suggest new insights on neuroprotection for this disease

Lack of Accuracy for the Proposed 'Dubois Criteria' in Alzheimer's Disease: A Validation Study from the Swedish Brain Power Initiative

Background/Aims: Our purpose was to investigate whether the new research criteria for Alzheimer's disease proposed in 2007 by Dubois et al. are valid in a naturalistic memory clinic sample. Method: Retrospective diagnostic analyses were carried out to compare the traditional diagnostic criteria for dementia with the new criteria suggested by Dubois et al. No patient had gone through all procedures postulated as additional features in the proposed new Dubois criteria. Material: Two independent experienced geriatricians re-examined 150 complete patients' records. The study physicians were blinded to any of the results of the core and additional features suggested by Dubois et al. to avoid circular diagnostic bias. Results: Among our 96 patients with a clinical diagnosis of subjective cognitive impairment and/or mild cognitive impairment, 2 of the patients with subjective cognitive impairment and 5 patients with mild cognitive impairment would classify as pre-dementia Alzheimer's disease according to the Dubois criteria. In our 23 Alzheimer patients diagnosed clinically, only 12 of the cases fulfilled the criteria for Alzheimer's disease suggested by Dubois et al. Interpretation: The proposed new criteria for Alzheimer's disease are valid in 55% of our patients clinically diagnosed as having full-blown Alzheimer dementia. Additionally, 7.3% 'true' Alzheimer cases will be identified in a group of 96 clinically non-demented patients. Our results show that there is a large heterogeneity in a clinical naturalistic sample of patients with an Alzheimer phenotype. Conclusion: There is a need to further validate the currently existing biomarkers in large unselected samples and avoid the pitfall of workup bias and circular diagnostic processes. Additionally, valid age-specific cut-off values for the diagnostic markers in question have to be defined. Copyright (C) 2010 S. Karger AG, Base

Age and diagnostic performance of Alzheimer disease CSF biomarkers.

Item does not contain fulltextOBJECTIVES: Core CSF changes in Alzheimer disease (AD) are decreased amyloid beta(1-42), increased total tau, and increased phospho-tau, probably indicating amyloid plaque accumulation, axonal degeneration, and tangle pathology, respectively. These biomarkers identify AD already at the predementia stage, but their diagnostic performance might be affected by age-dependent increase of AD-type brain pathology in cognitively unaffected elderly. METHODS: We investigated effects of age on the diagnostic performance of CSF biomarkers in a uniquely large multicenter study population, including a cross-sectional cohort of 529 patients with AD dementia (median age 71, range 43-89 years) and 304 controls (67, 44-91 years), and a longitudinal cohort of 750 subjects without dementia with mild cognitive impairment (69, 43-89 years) followed for at least 2 years, or until dementia diagnosis. RESULTS: The specificities for subjects without AD and the areas under the receiver operating characteristics curves decreased with age. However, the positive predictive value for a combination of biomarkers remained stable, while the negative predictive value decreased only slightly in old subjects, as an effect of the high AD prevalence in older ages. CONCLUSION: Although the diagnostic accuracies for AD decreased with age, the predictive values for a combination of biomarkers remained essentially stable. The findings highlight biomarker variability across ages, but support the use of CSF biomarkers for AD even in older populations

Progression of Alzheimer Disease in Europe: Data from the European ICTUS Study

Item does not contain fulltextThe clinical progression of Alzheimer disease (AD) was studied in European subjects under treatment with AChE inhibitors (AChE-I) in relation to geographical location over a 2-years period. One thousand three hundred and six subjects from 11 European countries were clustered into 3 regions (North, South, West) and investigated with biannual follow-up over 2 years. Primary outcomes were cognitive, functional and behavioral measures. Caregiver burden, hospital admission and admission to nursing home were also recorded. Participant cognitive function declined non-linearly over time (MMSE: -1.5 pts/first year, -2.5 pts/second year; ADAScog: + 3.5 pts/first year, + 4.8 pts/second year), while the progression of behavioral disturbances (NPI scale) was linear. Neither scale showed regional differences, and progression of the disease was similar across Europe despite different health care systems. Functional decline (ADL, IADL) tended to progress more rapidly in Southern Europe (p=0.09), while progression of caregiver burden (Zarit Burden Interview) was most rapid in Northern Europe (5.6 pts/y, p=0.04). Incidences of hospital admission (10.44, 95%CI: 8.13-12.75, p < 0.001) and admission to nursing home (2.97, 95%CI: 1.83-4.11, p < 0.001) were lowest in Southern Europe. In general cognitive and functional decline was slower than in former cohorts. European geographical location reflecting differences in culture and in health care system does not impact on the progression of AD but does influence the management of AD subjects and caregiver burden

Cell Therapy for Epilepsy

This volume provides a comprehensive, state-of-the art review of the field of cell therapy. The volume begins with an overview of the breadth of the field and then turns to overviews of imaging technologies that can aid in both safety and efficacy evaluations. The book then turns to numerous contributions detailing the rapidly growing field of stem cell therapies. These sections cover our understanding of the natural roles of stem cells in biology and human disease and then touches on several of the more prominent areas where stem cells are moving rapidly into clinical evaluation including neurodegenerative diseases, muscular dystrophy, cardiac repair, and diabetes. The volume concludes with contributions from experts in oncology, ophthalmology, stem cells, 3-D printing, and biomaterials where the convergence of expertise is leading to unprecedented insights into how to minutely control the in vivo fate and function of transplanted and/or endogeneously mobilized cells. Finally, the book provides insights into the pivotal relationship between academic and industrial partnerships. This volume is designed to touch on the major areas where the field will make its greatest and most immediate clinical impacts. This text will provide a useful resource for physicians and researchers interested in the rapidly changing filed of cell therapy