CCN1 secreted by human adipose-derived stem cells enhances wound healing and promotes angiogenesis through activating the AKT signalling pathway.

Abstract

The study aimed to explore the role of cellular communication network factor 1 (CCN1) an extracellular matrix protein in hADSC-treated wound healing. Immunofluorescence and enzyme-linked immunosorbent assays (ELISA) were used to demonstrate the secretion of CCN1 by hADSCs, isolated from human fat tissue. We investigated the role of CCN1 in wound healing by knockdown of CCN1 expression in hADSCs using CCN1 siRNA. Conditioned medium of hADSCs or hADSCs with CCN1 knocked down (hADSC-CMCCN1↓ ) was collected. After treatment with plain DMEM/F12, hADSC-CM, hADSC-CMCCN1↓ , or recombinant human CCN1 (rhCCN1), the wound healing abilities of human umbilical vascular endothelial cells (HUVECs) were assayed, and the AKT, also known as protein kinase B (PKB), signalling pathway was detected using western blotting. Next, we created full-thickness skin wounds on the backs of the mice and different treatments were applied to the wound surface. Wound size was measured using a digital camera on days 0-10, and evaluated. H&E and immunohistochemical staining were performed, and laser Doppler perfusion imaging was used to evaluate blood perfusion. The wound model and wound-healing assay showed that the hADSCs-CM and rhCCN1 groups had enhanced wound healing compared to the hADSCs-CMCCN1↓ group. Further, CCN1 and hADSCs-CM promoted the proliferation and migration of HUVECs through the AKT signalling pathway. We concluded that CCN1 secreted by hADSCs enhances wound healing and promotes angiogenesis by activating the AKT signalling pathway. CCN1 plays a vital role in the regulation of hADSCs-CM during wound healing.