Amyloid β, lipid metabolism, basal cholinergic system, and therapeutics in Alzheimer\u27s disease

The presence of insoluble aggregates of amyloid β (Aβ) in the form of neuritic plaques (NPs) is one of the main features that define Alzheimer\u27s disease. Studies have suggested that the accumulation of these peptides in the brain significantly contributes to extensive neuronal loss. Furthermore, the content and distribution of cholesterol in the membrane have been shown to have an important effect on the production and subsequent accumulation of Aβ peptides in the plasma membrane, contributing to dysfunction and neuronal death. The monomeric forms of these membrane-bound peptides undergo several conformational changes, ranging from oligomeric forms to beta-sheet structures, each presenting different levels of toxicity. Aβ peptides can be internalized by particular receptors and trigger changes from Tau phosphorylation to alterations in cognitive function, through dysfunction of the cholinergic system. The goal of this review is to summarize the current knowledge on the role of lipids in Alzheimer\u27s disease and their relationship with the basal cholinergic system, as well as potential disease-modifying therapies

The Impairment of Blood-Brain Barrier in Alzheimer’s Disease: Challenges and Opportunities with Stem Cells

Alzheimer’s disease (AD) is the most common neurodegenerative disorder and its prevalence is increasing. Nowadays, very few drugs effectively reduce AD symptoms and thus, a better understanding of its pathophysiology is vital to design new effective schemes. Presymptomatic neuronal damage caused by the accumulation of Amyloid β peptide and Tau protein abnormalities remains a challenge, despite recent efforts in drug development. Importantly, therapeutic targets, biomarkers, and diagnostic techniques have emerged to detect and treat AD. Of note, the compromised blood-brain barrier (BBB) and peripheral inflammation in AD are becoming more evident, being harmful factors that contribute to the development of the disease. Perspectives from different pre-clinical and clinical studies link peripheral inflammation with the onset and progression of AD. This review aims to analyze the main factors and the contribution of impaired BBB in AD development. Additionally, we describe the potential therapeutic strategies using stem cells for AD treatment

Historical distribution of central nervous system tumors in the Mexican National Institute of Neurology and Neurosurgery

Objective. To determine the frequency of central nervous system (CNS) tumors in the first fifty years of the National Institute of Neurology and Neurosurgery of Mexico Manuel Velasco Suárez (Instituto Nacional de Neurología y Neurocirugía de México, INNN) from 1965 to 2014. Materials and methods. A total of 16 116 institutional records of CNS tumors were analyzed. The frequency and distribution of CNS tumors were evaluated by tumor type, patient age and patient gender. The annual relationship between CNS tumors and surgical discharges (SD) over the last 20 years was estimated. Results. The frequencies of most CNS tumors were consistent with those found worldwide, and the most common tumors were neuroepithelial tumors (33%), particularly astrocytic tumors (67%); meningeal tumors (26%); and pituitary tumors (20%). The incidence of pituitary tumors in these data was twice as high as that reported in other regions of the world, and the relationship between CNS tumors and SD was consistent over time (0.22-0.39). Conclusion. This study summarizes the largest sample of CNS tumor cases analyzed in Mexico and provides an important reference of the frequency of this tumor type in the country. This work will serve as a basis for conducting studies evaluating factors associated with the presence of CNS tumors and for identifying adequate public health interventions.  DOI: http://dx.doi.org/10.21149/spm.v58i2.778