Three-dimensional self-assembling nanofiber matrix rejuvenates aged/degenerative human tendon stem/progenitor cells.

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Cell Biology

Background:

• Tendon healing capacity declines with age, linked to pathological changes in human tendon stem/progenitor cells (hTSPCs).
• Aging affects the function and regenerative potential of hTSPCs, posing challenges for tendon repair in the elderly.

Purpose of the Study:

• To investigate the rejuvenating potential of 3D RADA peptide nanofiber hydrogels on aged human tendon stem/progenitor cells (A-TSPCs).
• To compare the effects of RADA and RADA/RGD hydrogels on A-TSPCs versus young/healthy TSPCs (Y-TSPCs).

Main Methods:

• Utilized RADA peptide hydrogels, functionalized with RGD motifs, to create a 3D nanofibrous niche for hTSPCs.
• Performed cell survival, apoptosis, and proliferation assays.
• Employed microscopy techniques (TEM, confocal, AFM) and quantitative PCR to analyze cell phenotype and gene expression.

Main Results:

• RADA and RADA/RGD hydrogels supported A-TSPCs similarly to Y-TSPCs.
• A-TSPCs in hydrogels showed rejuvenated morphology, cytoskeletal architecture, and comparable ultrastructure to Y-TSPCs.
• Gene expression profiles in A-TSPCs were similar to Y-TSPCs, with upregulation of tenogenesis and multipotency markers.

Conclusions:

• RADA-based hydrogels effectively rejuvenate aged hTSPCs by mimicking the native microenvironment.
• These peptide hydrogels show significant potential for directing cell behavior and addressing cell aging in tendon repair strategies.