Circulating, Cell-Free Micro-RNA Profiles Reflect Discordant Development of Dementia in Monozygotic Twins

Area of Science:

• Biochemistry
• Genetics
• Neuroscience

Background:

• Dementia diagnosis relies on clinical assessment, lacking reliable early biomarkers.
• Micro-RNAs (miRNAs) and cytokines are potential circulating biomarkers for neurodegenerative diseases.

Purpose of the Study:

• To investigate the association between circulating micro-RNA and cytokine levels with dementia diagnosis and cognitive performance.
• To identify potential miRNA and cytokine biomarkers for early dementia detection.

Main Methods:

• Plasma samples from 48 monozygotic twin pairs were analyzed.
• Microfluidic RT-qPCR quantified 46 miRNAs; multiplex immunoassays measured 10 cytokines.
• Associations with dementia diagnosis and cognitive scores were examined longitudinally and at baseline.

Main Results:

• 36 miRNAs and all cytokines were consistently detected.
• Micro-RNA profiles significantly associated with dementia diagnosis and cognitive scores.
• Cytokine levels showed trends suggesting chronic inflammation in dementia patients.
• Decreased miR-106a/miR-210 and increased miR-106b expression were notable in dementia cases.

Conclusions:

• Circulating micro-RNAs, particularly miR-106a, miR-210, and miR-106b, are promising biomarkers for dementia.
• These miRNAs may target pathways involved in vasculogenesis, lipoprotein transport, and amyloid precursor protein processing.