Adipose-derived Stem Cells and Wound Healing Are Progressively Impaired Long-term After Radiotherapy in Mice

Area of Science:

• Radiation oncology
• Stem cell biology
• Dermatology

Background:

• Deterministic radiation damage pathogenesis is unclear, but fibroinflammatory pathways are implicated.
• Hypothesis: Radiotherapy reduces adipose-derived stem/stromal cells (ASCs), hindering fibrosis and angiogenesis normalization, causing chronic radiation damage.

Purpose of the Study:

• To investigate the long-term effects of radiotherapy on ASCs and skin healing in a mouse model.
• To determine the correlation between ASC depletion and the progression of radiation-induced skin damage.

Main Methods:

• BALB/cfC3H mice underwent 4 weekly 10 Gy irradiations to the dorsal skin.
• Evaluated epithelialization time, tissue oxygen saturation, skin thickness, and CD34+/isolectin- ASC counts at 1, 3, 6, 9, and 12 months post-radiotherapy.

Main Results:

• Epithelialization time and tissue oxygen saturation increased significantly over time post-radiotherapy.
• CD34+/isolectin- ASC counts progressively decreased, particularly after 6 months.
• Subcutaneous fatty layer thickness significantly reduced from 3 months onwards.

Conclusions:

• Post-radiotherapy, ASCs decline over time, correlating with irreversible fibrosis, atrophy, and ischemia.
• This ASC depletion impairs wound healing and contributes to the progression of chronic radiation damage.