Intracellular amyloid formation in muscle cells of Aβ-transgenic Caenorhabditis elegans: determinants and physiological role in copper detoxification

Background: The amyloid β-peptide is a ubiquitous peptide, which is prone to aggregate forming soluble toxic oligomers and insoluble less-toxic aggregates. The intrinsic and external/environmental factors that determine Aβ aggregation in vivo are poorly understood, as well as the cellular meaning of this process itself. Genetic data as well as cell biological and biochemical evidence strongly support the hypothesis that Aβ is a major player in the onset and development of Alzheimer's disease. In addition, it is also known that Aβ is involved in Inclusion Body Myositis, a common myopathy of the elderly in which the peptide accumulates intracellularly. Results: In the present work, we found that intracellular Aβ aggregation in muscle cells of Caenorhabditis elegans overexpressing Aβ peptide is affected by two single amino acid substitutions, E22G (Arctic) and V18A (NIC). Both variations show decrease intracellular amyloidogenesis compared to wild type Aβ. We show that intracellular amyloid aggregation of wild type Aβ is accelerated by Cu2+ and diminished by copper chelators. Moreover, we demonstrate through toxicity and behavioral assays that Aβ-transgenic worms display a higher tolerance to Cu2+ toxic effects and that this resistance may be linked to the formation of amyloid aggregates. Conclusion: Our data show that intracellular Aβ amyloid aggregates may trap excess of free Cu2+ buffering its cytotoxic effects and that accelerated intracellular Aβ aggregation may be part of a cell protective mechanism

Muscle cell outside and inside: the nascent approach of a clinician

Understanding muscle cell in disease and health is an unfinished process. Following the lead of Jaime Alvarez, I have had the opportunity of working on two complementary approaches to this field. One is the study of muscle cell surface molecules. Both synaptic muscle molecules, such as the asymmetric form of acetylcholinesterase, and extrasynaptic molecules, such as the extracellular matrix proteoglycans, are regulated by the motor nerve activity. This illustrates one of Jaime's teachings: cell phenotypes are a dynamic process that reflects the influence of other cells (Alvarez, 2001). Proteoglycans have many functions, including growth factor receptors. Studying them in muscular dystrophy will contribute to the comprehension of the muscle regeneration failure, characteristic of this disease. Muscle cells are highly dependent upon energy production, and the mitochondriae produce most of it. These organelles are unique in having their own genome. Mutations in these genes have recently been recognized as the cause of human disease and originally in muscle pathology. The physiopathology of these diseases is summarized her

Clinical and Demographical Characteristics of Patients with Medication Overuse Headache in Argentina and Chile:Analysis of the Latin American Section of COMOESTAS Project

BACKGROUND: Data on the characteristics of Medication Overuse Headache (MOH) in Latin American (LA) are scarce. Here we report the demographic and clinical features of the MOH patients from Argentina and Chile enrolled in the multinational COMOESTAS project in the period 2008–2010. METHODS: The LA population was formed by 240 MOH subjects, 110 from Chile and 130 from Argentina, consecutively attending the local headache centres. In each centre, specifically trained neurologist interviewed and confirmed the diagnosis according to the ICHD-II criteria. A detailed history was collected on an electronic patient record form. RESULTS: The mean patient age was 38.6 years, with a female/male ratio of 8:2. The mean time since onset of the primary headache was 21 years, whereas duration of MOH was 3.9 years. The primary headache was migraine without aura in 77.5 % and migraine with aura in 18.8 %. Forty two % of the patients self-reported emotional stress associated with the chronification of headache; 43.8 % reported insomnia. The most overused medications were acute drug combinations containing ergotamine (70 %), NSAIDs (33.8 %) and triptans (5.4 %). CONCLUSION: Though little described, MOH is present also in LA, where it affects mostly women, in the most active decades of life. Some differences emerge as regards the demographic and clinical characteristics of MOH in this population as compared to Europe or Northern America. What seems more worrying about MOH in Argentina and Chile is that most patients overuse ergotamine, a drug that may cause serious adverse events when used chronically. These findings once more underscore the importance of properly diagnose and treat MOH

Mitochondrial DNA heteroplasmy of the m.3243A>G mutation in maternally inherited diabetes and deafness

El objetivo de este trabajo es evaluar el grado de heteroplasmia de la mutación m.3243A>G en diferentes tejidos obtenidos de una paciente afectada con MIDD (sangre, raíz de pelo, músculo y saliva) y evaluar su utilidad diagnóstica

The added value of an electronic monitoring and alerting system in the management of medication-overuse headache: A controlled multicentre study

Background Medication-overuse headache (MOH) is a chronic disabling condition associated with a high rate of relapse. Methods We evaluated whether the adoption of electronic-assisted monitoring, advice and communication would improve the outcome over a follow-up of 6 months in a controlled, multicentre, multinational study conducted in six headache centres located in Europe and Latin America. A total of 663 MOH subjects were enrolled and divided into two groups: the Comoestas group was monitored with an electronic diary associated with an alert system and a facilitated communication option, and the Classic group with a paper headache diary. Results We observed a significantly higher percentage of overuse-free subjects in the Comoestas group compared with the Classic group: 73.1 vs 64.1% (odds ratio 1.45, 95% confidence interval 1.07-2.09, p = 0.046). The Comoestas group performed better also regarding the number of days/month with intake of acute drugs and the level of disability [Migraine Disability Assessment Score: Comoestas group - 42.5 ± 53.6 (35.5-49.3) and Classic group - 27.5 ± 56.1 (20.6-34.3) ( p < 0.003)]. Conclusion The adoption of the electronic tool improved the outcome of patients suffering from MOH after withdrawal from overused drugs. Information and communication technology represents a valid aid for optimizing the management of chronic conditions at risk of worsening or of relapsing. Trial registration The trial was registered at ClinicalTrials.gov (no. NCT02435056)