Cerebellar morphometry in sporadic and familial Amyotrophic Lateral Sclerosis (ATXN1 and ATXN2)

• Grant number: 21/11715-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2022
• End date: October 31, 2024
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Marcondes Cavalcante Franca Junior
• Grantee: Paulo Schneider Wolmer
• Host Institution: Faculdade de Ciências Médicas (FCM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease that causes destruction of motor neurons, both superior (SMN) and inferior (IMN), and that causes progressive paralysis of the somatic muscles. The disease is presented in two forms: sporadic (sALS), more frequent, around 90% of cases; and familial (fALS), 5-10% of cases. Regarding fALS, several genetic alterations have been implicated in its pathogenesis. Repeat expansions of CAG triplets in the ATXN1 and ATXN2 genes (that produce a polyglutamine tract (polyQ) in the ataxin 1 and ataxin 2 proteins respectively) are considered risk factors for the development of the disease and, although imaging studies exist in patients with these mutations, approaches have had little cerebellar focus for the time being. Considering that intermediate repeat expansions in the ATXN1 and ATXN2 genes are considered risk factors for the developmento of ALS, while complete expansions lead to spinocerebellar ataxias (SCAs) with significant atrophy of the cerebellum, the question arises about the involvement of the cerebellum in patients with ALS related to mutations in these genes. Thus, given the absence of prominent cerebellar lesions in qualitative visual neuroimaging analyzes of these patients, a detailed quantitative analysis of their cerebellar volumes by magnetic resonance imaging becomes relevant. Thus, to better understand the genotype-phenotype correlation, as well as the pathophysiology of the disease, this study aims to assess the cerebellum volumes of the patients with ALS-ATXN1, ALS-ATXN2, sporadic ALS and a control group. The volumes of the cerebellar lobules will be compared between the groups and related to the clinic conditions of the disease. All the patients included in this study are followed up in the neurogenetics and neuromuscular diseases clinics at the Hospital de Clínicas of the State University of Campinas.(AU)