Exosomes from human adipose-derived mesenchymal stem cells attenuate localized scleroderma fibrosis by the let-7a-5p/TGF-βR1/Smad axis

Red propolis extract associated to platelet-rich plasma and stromal cells with focus in cell therapy and functional tissue regeneration

The use of platelet-rich plasma (PRP) and adipose-derived stromal cells (ADSC) have been investigated as a form of wound healing enhancement. The objective of this work was to evaluate the association of red propolis (RP) and PRP as inducers of ADSC for application in tissue regeneration. Adipose tissue post-collection and post-cryopreservation was isolated with type II collagenase, characterized by flow cytometry, and differentiated into osteogenic, chondrogenic and adipose cell. The viability of ADSC was evaluated when exposed to different concentrations of RP using the MTT and trypan blue assay. Acridine orange and ethidium bromide (AO/EB) was performed to evaluate cell death events. Horizontal migration methods were investigated in ADSC using autologous and homologous PRP associated with RP (PRP/RP). All assays were processed in triplicate. Flow cytometry and cellular differentiation showed that type II collagenase was effective for isolating ADSC post-collection and post-cryopreservation. RP extracts at concentrations of up to 50 μg.mL-1 presented no cytotoxic effects. Association of PRP and RP at 25 and 50 μg.ml-1 influenced ADSC migration, with total closure on the seventh day after exposition. The results here presented could stimulate proliferation of ADSC cells that may contribute directly or indirectly to the reconstructive process of tissue regeneration.

Exosomes from adipose-derived mesenchymal stem cell improve diabetic wound healing and inhibit fibrosis via miR-128-1-5p/TGF-β1/Smad axis

OBJECTIVE

Difficult-to-heal wound is a prevalent and significant complication of diabetes, characterized by impaired functionality of epithelial cells such as fibroblasts. This study aims to investigate the potential mechanism of ADSC-Exos promoting diabetic wound healing by regulating fibroblast function.

MATERIALS AND METHODS

ADSC-Exos were confirmed through TEM, NTA, and Western Blot techniques. The study conducted on rat skin fibroblasts (RSFs) exposed to 33 mmol/L glucose in vitro. We used cck-8, EDU, transwell, and scratch assays to verify the proliferation and migration of RSFs. Furthermore, levels of TGF-β1 and α-SMA proteins were determined by immunofluorescence and Western Blot. RSFs were transfected with miR-128-1-5p mimics and inhibitors, followed by quantification of TGF-β1, α-SMA, Col I and Smad2/3 protein levels using Western Blot. In vivo, the effects of ADSC-Exos on diabetic wounds were assessed using digital imaging, histological staining, as well as Western Blot analysis.

RESULTS

In vitro, ADSC-Exos significantly enhanced proliferation and migration of RSFs while reducing the expression of TGF-β1 and α-SMA. In vivo, ADSC-Exos effectively promoted diabetic wound healing and mitigated scar fibrosis. Additionally, ADSC-Exos exhibited elevated levels of miR-128-1-5p, which targets TGF-β1, resulting in a notable reduction in TGF-β1, α-SMA, Col I and smad2/3 phosphorylation in RSFs.

CONCLUSION

In conclusion, our results demonstrated that ADSC-Exos promoted diabetic wound healing, and inhibited skin fibrosis by regulating miR-128-1-5p/TGF-β1/Smad signaling pathway, which provides a promising innovative treatment for diabetic wound healing.