Relationship Between miRNA and Neurodegenerative Diseases Such as Alzheimer's disease, Parkinson's, Huntington's...

The regulatory roles of miRNAs on CNS homeostasis, neuronal differentiation, and synaptic plasticity make these molecules indispensable for healthy brain functions. miRNA dysregulation, by triggering abnormal neurodevelopment, has a critical impact on the etiology and progression of neurodegenerative diseases. MicroRNAs (miRNAs) are short, single-stranded, non-coding ribonucleic acid (RNA) molecules, 18 to 24 nucleotides long. They play a role in posttranscriptional gene regulation by binding to complementary sequences on messenger RNA (mRNA), thereby promoting mRNA degradation or preventing translation into protein. MiRNAs are essential regulators of the genome because they bind targets and alter gene expression. MiRNA biogenesis and functions are tightly regulated, and their dysregulation is associated with various diseases, including cancer, cardiovascular diseases, and neurodegenerative disorders. In particular, disruption of the Blood-Brain Barrier in neurodegenerative diseases allows molecules to leak into the bloodstream, enabling the detection of miRNAs in other body fluids and making these fluids potential biomarker sources. In this context, miRNAs can be measured in blood, cerebrospinal fluid, and other biological samples. It has significant potential for early diagnosis, disease progression monitoring, and evaluation of treatment efficacy. In this review, the relationship between MiRNAs and neuronal degeneration diseases was evaluated. In this review, prepared in light of the current literature scanned through the PubMed database, we examined data from the last 5 years (2021-2026) on neurodegenerative diseases associated with miRNA dysregulation, including Alzheimer's Disease (AD), Parkinson's Disease (PD), Amyotrophic Lateral Sclerosis (ALS), and Huntington's Disease (HD).