MicroRNA and Alzheimer’s disease: Diagnostic biomarkers and potential therapeutic targets

MicroRNAs (miRNAs), small non-coding RNAs ranging from 19 to 25 nucleotides in length, are key regulators of gene expression that function primarily by inhibiting the translation of target mRNAs. Recent studies have suggested that miRNAs play important roles in regulating key aspects in the pathology of Alzheimer's disease, including the modulation and accumulation of amyloid-beta and tau proteins. Moreover, miRNAs have been implicated in the regulation of neuroinflammation through various inflammatory pathways, notably the nuclear factor kappa B signaling cascade. Additional emerging evidence has shown that miRNAs regulate synaptic growth and maturation, and they perform promising roles in regulating neuronal death and development. miRNAs also offer a novel avenue for direct reprogramming of neurons, representing a promising strategy for Alzheimer's disease treatment. The regulation of miRNA biogenesis and the post-transcriptional modifications of miRNAs are critical factors in Alzheimer's disease pathology, influencing miRNA activity and disease progression. In this review, we comprehensively explore the role of different miRNAs in regulating various pathological processes associated with Alzheimer's disease, focusing primarily on four representative miRNAs: miR-9, miR-29, miR-126, and miR-146a for further exploration. We also discuss the influence of miRNA biogenesis on Alzheimer's disease, emphasizing how dysregulation of miRNA processing may contribute to the disease. Additionally, we highlight the potential of miRNAs as both diagnostic biomarkers and therapeutic targets in Alzheimer's disease, along with promising vector delivery strategies aimed at improving clinical outcomes. Finally, we discuss the challenges and limitations associated with the use of miRNAs in the diagnosis and treatment of Alzheimer's disease. By reviewing the current clinical applications of miRNAs as biomarkers and therapeutic agents, we aim to provide insights that will inform future research and development in this promising field.