Letter to the Editor: Low-energy fractional carbon dioxide laser priming of mesenchymal stem cell-derived exosomes: A photothermal boost for diabetic wound angiogenesis.

The study by Chen et al recently published in World Journal of Methodology provides a significant advancement in the field of diabetic wound healing by demonstrating that low-energy fractional carbon dioxide laser preconditioning (40 mJ/cm², 300 Hz, 5% density) significantly enhances the angiogenic potential of adipose-derived mesenchymal stem cell-derived exosomes. This single-exposure, 10 mm × 10 mm Micro-DeepFX protocol raised the culture temperature to 42.7 °C and increased exosomal sphingosine-1-phosphate (S1P) content by about 1.8-fold (enzyme-linked immunosorbent assay: 2.4 ng/109 vs 1.3 ng/109 particles, P < 0.01). Through carefully controlled photothermal stimulation, the authors enriched exosomal S1P) content, thereby activating the S1PR1/AKT/HIF-1α signalling axis in endothelial cells. This mechanistic cascade resulted in improved proliferation, migration, and tube formation, ultimately accelerating wound closure in diabetic mouse models. The work under discussion highlights a clinically feasible, non-chemical strategy for augmenting exosome bioactivity and offers strong translational potential. However, the heterogeneity of donors, the limited mechanistic depth of exosomal lipid remodelling, and the need for validation in larger and more clinically representative models warrant further investigation.