hUCB-MSCs Secreted Exosomal miR-21-5p Promotes Vascular Endothelial Tip Cell Proliferation and Migration by...

Area of Science:

• Regenerative Medicine
• Cell Biology
• Vascular Biology

Background:

• Therapeutic angiogenesis presents a novel strategy for Peripheral Arterial Disease (PAD) treatment.
• Human Umbilical Cord Blood Mesenchymal Stem Cells (hUCB-MSCs) and their exosomes show potential in promoting neovascularization.
• These cells and exosomes are key research targets for therapeutic angiogenesis.

Purpose of the Study:

• To investigate the effects of hUCB-MSCs and their exosomes on vascular endothelial tip cell proliferation and migration.
• To identify key molecular mechanisms underlying these effects.

Main Methods:

• Cultivation and identification of endothelial tip cells and hUCB-MSCs.
• Exosome isolation and characterization.
• Co-culture experiments and exosome incubation with tip cells.
• Quantitative PCR (qPCR) for microRNA and gene expression analysis (miR-21-5p, TGF-β1).
• Western blotting for protein analysis.
• Cell proliferation (CCK-8, EdU), migration (Transwell), and apoptosis (flow cytometry) assays.

Main Results:

• hUCB-MSCs and exosomes significantly promoted tip cell proliferation and migration, while inhibiting apoptosis.
• Exosomes demonstrated superior efficacy compared to hUCB-MSCs.
• Exosomal miR-21-5p was identified as a crucial factor, downregulating TGF-β1 in tip cells.
• Increased miR-21-5p enhanced tip cell proliferation and migration and reduced apoptosis, an effect reversed by TGF-β1.

Conclusions:

• hUCB-MSC-derived exosomes, particularly those enriched with miR-21-5p, enhance endothelial tip cell function.
• This enhancement is achieved through the targeted suppression of TGF-β1.
• These findings suggest a promising therapeutic potential for hUCB-MSC exosomes in PAD treatment.