Feedback interaction of research, advocacy, and clinical care applied to ALS research in South America

Mitochondrial Quality Control Strategies: Potential Therapeutic Targets for Neurodegenerative Diseases?

Many lines of evidence have indicated the therapeutic potential of rescuing mitochondrial integrity by targeting specific mitochondrial quality control pathways in neurodegenerative diseases, such as Parkinson's disease, Huntington's disease, and Alzheimer's disease. In addition to ATP synthesis, mitochondria are critical regulators of ROS production, lipid metabolism, calcium buffering, and cell death. The mitochondrial unfolded protein response, mitochondrial dynamics, and mitophagy are the three main quality control mechanisms responsible for maintaining mitochondrial proteostasis and bioenergetics. The proper functioning of these complex processes is necessary to surveil and restore mitochondrial homeostasis and the healthy pool of mitochondria in cells. Mitochondrial dysfunction occurs early and causally in disease pathogenesis. A significant accumulation of mitochondrial damage resulting from compromised quality control pathways leads to the development of neuropathology. Moreover, genetic or pharmaceutical manipulation targeting the mitochondrial quality control mechanisms can sufficiently rescue mitochondrial integrity and ameliorate disease progression. Thus, therapies that can improve mitochondrial quality control have great promise for the treatment of neurodegenerative diseases. In this review, we summarize recent progress in the field that underscores the essential role of impaired mitochondrial quality control pathways in the pathogenesis of neurodegenerative diseases. We also discuss the translational approaches targeting mitochondrial function, with a focus on the restoration of mitochondrial integrity, including mitochondrial dynamics, mitophagy, and mitochondrial proteostasis.

Epidemiological and genetic features of amyotrophic lateral sclerosis in Latin America and the Caribbean: a systematic review

Introduction: Heterogeneity of amyotrophic lateral sclerosis (ALS) has been suggested in terms of epidemiology, phenotypes and genetics between geographic areas and populations. However, there is limited information in Latin America. We conducted a systematic review that aimed to describe the epidemiology, frequency of genetic mutations, clinical characteristics and survival of ALS patients in this region. Methods: We reviewed Medline, Scopus, Scielo and LILACS databases up to April 2020. The search terms "Amyotrophic Lateral Sclerosis" or "Motor Neuron Disease" were used in combination with the list of Latin American countries from the United Nations. All observational studies were included. A methodological overview was performed using the principles of descriptive epidemiology. Results: Overall, 1364 publications were identified and 36 studies were selected, covering 13 Latin American countries. According to the original reports, ALS occurrence varied among countries with a standardized incidence ranging from 0.3 per 100,000 person-years follow up (PYFU) in Ecuador to 3.6 per 100,000 PYFU in Uruguay. A low proportion of the C9orf72 repeat expansion was reported in Cuba and Brazil. We identified age at onset between 50 and 60 years. Survival time was higher than 40 months in half of the studies. Data from multiethnic populations reported a higher risk of developing ALS in Caucasians compared to admixed and Black populations. Conclusion: This review provides a perspective of ALS variability across Latin America and highlights specific differences when comparing to Europe and North America. However, we cannot draw firm conclusions because of different methodological concerns within the studies.