Thioredoxin-loaded nanocomposite wound dressing for the delivery of adipose derived stem cells for wound healing applications.

In the current research, Thioredoxin was loaded into chitosan nanoparticles and then loaded into the matrix of collagen hydrogel containing adipose-derived stem cells (ASCs). In vitro studies including Scanning electron microscopy imaging, cell viability assay, cell migration assay, swelling assay, release assay, radical scavenging assay were performed in order to characterize the dressings. Then, the wound healing activity of these scaffolds were studied in a rat model of wound healing. Our findings indicate that the scaffolds markedly accelerated wound closure, enhanced epithelial regeneration, and increased collagen deposition. The wound closure values for the developed dressings were 60.507 ± 2.287% on Day 7 and 95.270 ± 2.600% on Day 14. ELISA results demonstrated an upregulation of VEGF, b-FGF, and TGF-β expression, while TNF-α and IL-6 levels were significantly reduced. For our developed dressings, VEGF levels were 661.307 ± 80.195 pg/mL, while bFGF was detected at 524.410 ± 81.040 pg/mL. The concentration of TGF-β was 315.357 ± 54.783 pg/mL, and TNF-α was measured at 176.093 ± 43.934 pg/mL. Additionally, IL-6 levels were found to be 187.577 ± 40.860 pg/mL. Our results suggest that our developed hydrogel system has improved wound healing via improving angiogenesis and modulating inflammation. These mechanisms can be attributed to the proangiogenic and immunomodulatory activities of ASCs and the antioxidative properties of Thioredoxin.