Circulating Biomarker for Amyotrophic Lateral Sclerosis (ALS)

Amyotrophic Lateral Sclerosis (ALS) is a rare disease with a worldwide incidence of 2-3 cases per 100,000 individuals/year and it is characterized by progressive neurodegeneration of motor neurons. When motor neurons degenerate the ability of the brain to initiate and control muscle movement is lost. ALS manifests in two forms: Familiar ALS (FALS) with inherited risk genotypes, accounts for only 10% of cases and sporadic ALS (SALS) without apparent heritability accounts for 90% of cases. ALS can occur in both female and male subjects at any age but is more common in people aged over 40.

Although the molecular mechanism underlying the pathogenesis of ALS is still under investigation, recent research has revealed that diseases affecting motor neurons may be associated to alterations of RNA metabolism and biogenesis of small non-coding micro RNAs (miRNAs). miRNAs are circulating molecules, whose expression profiles are widely described to have an important potential in monitoring the progression of a disease, to promote the development of more targeted therapies and/or to determine the effectiveness of treatments. Altered patterns of specific miRNAs expression have been described in several pathological conditions. Evidence shows a significant reduction in the levels of certain miRNAs also in patients with ALS. Among others, miRNA-218 has been described to play a critical role in the onset of motor neurons differentiation and in establishing cell identity and fate.

Changes in the levels of miRNA-218 in the serum of ALS patients may potentially provide useful tools to determine the possible association with this disease and to candidate it as indicator of disease progression.