ABSTRACT
Ischemic dysfunction is an important global health problem. Vascular endothelial cells(VECs) play a key role in angiogenesis, and insufficient vascular remodeling may lead to chronic nonhealing wounds. Therefore, effective VEC generation strategies of exploration help improve angiogenesisin damaged tissues. Embryonic stem cells (ESCs) are widely used in the study of tissueendothelialization, and endothelial progenitor cells (EPCs) are indispensable parts of the development ofVECs. The aims of this study were to find a rapid, easily screened and reproducible method for thederivation of EPCs from mouse embryonic stem cells (mESCs), and obtain VECs with high survival ratesand strong functions from the directed differentiation of the EPCs. The results showed that mESCs weredifferentiated into " stepping stone" -like progenitor cells with active proliferative ability by 10 ng / mLVEGF and 5 ng / mL bFGF. At the same time, the method of differential adherence was helpful for theselection of EPCs, and EPCs induced high expression of CD133 and CD34 (The relative expressionlevels were 0. 88 ± 0. 04 and 2. 12 ± 0. 02, respectively) for 3 days. Then EPCs were digested withacctuse enzymes, and induced to differentiate into vascular endothelial-like cells by 50 ng / mL VEGF and25 ng / mL bFGF for 7 days. The endothelial cells not only expressed endothelial marker genes (CD31, CD144, LAMA5, Tek, KDR and vWF),and marker proteins CD31, CD144 and LAMA5 (The relativeexpression levels were 1. 07 ± 0. 03, 0. 60 ± 0. 02 and 0. 70 ± 0. 02, respectively), but also had thegood ability of migration, tubulogenesis and formation of W-P bodies. Moreover, PBS, EPC and VECwere used to treat wounds of the same size. Both EPC and VEC could accelerate the degree of tissuehealing (The relative healing rates were 78. 93 ± 75. 35%, 95. 57 ± 83. 73% and 100. 00 ± 0. 00%, respectively), and VEC significantly enhanced the ability of wound angiogenesis and inflammatoryresponses. In consequence, this study preliminarily confirmed that mESC-derived EPCs coulddifferentiate into VECs after directional induction for 7 days, which had good function of tissue repair. The physiological pathway on stem cells by stimulating angiogenesis is expected to become a new target fortissue remodeling.
ABSTRACT
The skin is one of the most important tissues in mammals. When the skin is damaged, the damaged tissue is repaired through the physiological and psychological effects of a series of wound healing reactions to achieve tissue regeneration. The regeneration reaction mainly occurs in the early stage of embryonic development, and the wound self-healing ability weakens as the body matures. The process of tissue remodeling in mammals is more complicated. Incorrect signal guidance may cause complications and lead to abnormal wound healing. Studies have shown that the homeostasis of the wound microenvironment and the auxiliary effects of signalling molecules are important factors in healing. The Notch signaling pathway is involved in the regulation of epithelial macrophage recruitment, vascular endothelial cell regeneration and other wound healing stages. Wnt signaling promotes the proliferation of wound epidermal stem cells and the formation of vascular network structure. The Hedgehog signal drives the development of hair follicles at the wound and the regeneration of the surrounding tissues, and the TGF-beta signal contributes to the formation of multicellular layers and scar reduction during healing. This article focuses on the regulation of the Notch signaling pathway and the interaction of Notch and related signaling molecules in wound healing. We summarize the latest developments in tissue engineering research on signal molecules, analyze the signal interaction mechanism of the wound microenvironment, and provide a theoretical basis for the treatment of long-term wound healing and excessive wound healing.
