MicroRNA-based recent research developments in Alzheimer's disease

Alzheimer's disease (AD) is a chronic neurodegenerative disorder that is characterized by memory and physical impairment in aged individuals. microRNAs (miRNAs) are small, single-stranded noncoding RNAs that induce translational repression by binding to the 3' UTR of a target mRNA. miRNAs play a crucial role in neurological activity by mediating cellular proliferation, synaptic plasticity, apoptosis and more. Ongoing research in patents and clinical trials have called attention to promising miRNAs as biomarkers and therapeutics in AD. Recent research has shown that miRNAs are aberrantly expressed in AD brain, blood, cerebrospinal fluid and serum. Attenuated miRNA expressions have diagnostic potential in AD by interacting with amyloid-β synthesis, phosphorylated tau, and neurofibrillary tangles. In this study, miRNA-29a, miRNA-125b, miRNA-34a, miRNA-146a, and miRNA-155 have shown promise as potential biomarker candidates for AD. Improving cognitive symptoms can be traced to restoring the endogenous miRNA activity by synthesizing miRNA mimics and miRNA antisense oligonucleotides. miRNA-483-5p, miRNA-188-5p, miRNA-219, miRNA135a/5p, miRNA-23/23b-3p, miRNA-124, and miRNA-455-3p are growing therapeutics for AD. However, miRNA-based therapeutics struggle outside of preclinical testing. miRNA-107, miRNA-206, miRNA-30/7, and miRNA-142-3p face bottlenecks in clinical trials due to a lack of experimental design, transparency and volunteer size. Patenting recent miRNA-based developments demonstrates the commitment in identifying a new biomarker and/or therapeutic for AD.