miRNAs and Stem Cells as Promising Diagnostic and Therapeutic Targets for Alzheimer's Disease

Alzheimer's disease (AD) is a cumulative progressive neurodegenerative disease characterized mainly by impairment in cognitive functions accompanied by memory loss, disturbance in behavior and personality, and difficulties in learning. Although the main causes of AD pathogenesis are not fully understood yet, amyloid-beta peptides and tau proteins are supposed to be responsible for AD onset and pathogenesis. Various demographic, genetic, and environmental risk factors are involved in AD onset and pathogenesis such as age, gender, several genes, lipids, malnutrition, and poor diet. Significant changes were observed in microRNA (miRNA) levels between normal and AD cases giving hope for a diagnostic procedure for AD through a simple blood test. As yet, only two classes of AD therapeutic drugs are approved by FDA. They are classified as acetylcholinesterase inhibitors and N-methyl-D-aspartate antagonists (NMDA). Unfortunately, they can only treat the symptoms but cannot cure AD or stop its progression. New therapeutic approaches were developed for AD treatment including acitretin due to its ability to cross blood-brain barrier in the brain of rats and mice and induce the expression of ADAM 10 gene, the alpha- secretase of human amyloid-beta protein precursor, stimulating the non-amyloidogenic pathway for amyloid-beta protein precursor processing resulting in amyloid-beta reduction. Also stem cells may have a crucial role in AD treatment as they can improve cognitive functions and memory in AD rats through regeneration of damaged neurons. This review spotlights on promising diagnostic techniques such as miRNAs and therapeutic approaches such as acitretin and/or stem cells keeping in consideration AD pathogenesis, stages, symptoms, and risk factors.

Automated summary

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by cognitive impairment, memory loss, and behavioral changes. The exact causes of AD are not fully understood, but amyloid-beta peptides and tau proteins are believed to play a role. Various demographic, genetic, and environmental risk factors contribute to the onset and progression of AD. MicroRNA levels show promise as a diagnostic tool for AD, and while there are currently only two FDA-approved therapeutic drugs, new approaches such as acitretin and stem cells show potential for treatment. This review highlights promising diagnostic techniques and therapeutic approaches for AD.