Reduced Expression of Selected Exosomal MicroRNAs Is Associated with Poor Outcomes in Patients with Acute Stroke...

Area of Science:

• Neuroscience
• Molecular Biology
• Biochemistry

Background:

• Reperfusion therapy aims to restore brain blood flow post-stroke, but functional independence remains limited for many patients.
• MicroRNAs (miRNAs) are implicated in regulating cerebral ischemia/reperfusion injury, with exosomal transfer potentially influencing recipient cell function.
• Understanding exosomal miRNA dynamics is crucial for predicting stroke outcomes and developing targeted therapies.

Purpose of the Study:

• To investigate serum exosomal miRNA levels in stroke patients undergoing different reperfusion therapies.
• To correlate miRNA expression with stroke treatments and functional outcomes (modified Rankin Scale).
• To explore the role of differentially expressed miRNA (DEmiRNA) target genes in the brain's response to reperfusion.

Main Methods:

• Serum samples were collected from stroke patients (aspirin, rt-PA, MT, or rt-PA/MT) on days 1 and 10 post-stroke.
• Serum exosomal miRNA levels were quantified using qRT-PCR.
• DEmiRNAs, their targets, and associated pathways were identified; functional outcomes were assessed using the modified Rankin Scale (mRS).

Main Results:

• The combination therapy (rt-PA/MT) uniquely reduced DEmiRNA levels by day 10 compared to other treatments.
• Patients with unfavorable mRS scores showed decreased levels of miR-17, miR-20, miR-186, and miR-222 after combined therapy.
• Functional analysis linked DEmiRNA targets to cytoskeleton remodeling, cell death, autophagy, inflammation, and dementia pathways.

Conclusions:

• Lower serum exosomal miRNA levels following rt-PA/MT may predict unfavorable stroke outcomes.
• These decreased miRNA levels could promote cell death and neurodegenerative processes, contributing to poor recovery.
• Targeting exosomal miRNA pathways presents a potential therapeutic strategy for improving stroke recovery.