Effects of Placenta-Derived Human Amniotic Epithelial Cells on the Wound Healing Process and TGF-β Induced Scar Formation in Murine Ischemic-Reperfusion Injury Model.

Abstract

Pressure ulcers (PUs), a result of ischemic reperfusion (IR) injuries, are prevalent skin problems which show refractoriness against standard therapeutic approaches. Besides, scar formation is a critical complication of ulcers that affects functionality and the skin's cosmetic aspect. The current study aimed to investigate the effects of placenta-derived human amniotic epithelial cells (hAECs), as important agents of regenerative medicine and stem cell therapy, on accelerating the healing of IR ulcers in mice. We also evaluated the effects of these cells on reducing the TGFβ-induced scar formation. Male Balb/c mice at the age of 6-8weeks were subjected to three IR cycles. Afterward, the mice were divided into three experimental groups (n = 6 per group), including the control group, vehicle group, and hAECs treatment group. Mice of the treatment group received 100μL of fresh hAECs 1 × 106 cell/ml suspension in PBS. Afterward, mice were assessed by histological, stereological, molecular, and western blotting techniques at 3, 7, 14, and 21days after wounding. The histological and stereological results showed the most diminutive scar formation and better healing in the hAECs treated group compared to control group. Furthermore, our results demonstrated that the expression level of Col1A1 on days 3, 14, and 21 in the hAECs treated group was significantly lower than control. Additionally, injection of hAECs significantly reduced the expression level of Col3A1 on days 3, 7, and 21 while increased Col3A1 on the day 14. Otherwise, in the hAECs treated group, the expression levels of VEGFA on days 7 and 14 were higher, which showed that hAECs could promote angiogenesis and wound healing. Also, cell therapy significantly lowered the protein levels of TGF-β1 on day 14, while the protein level of TGF-β3 on day 14 was significantly higher. This data could demonstrate the role of hAECs in scar reduction in IR wounds. These results suggest that hAECs can promote re-epithelialization and wound closure in an animal model of PU. They also reduced scar formation during wound healing by reducing the expression of TGF-β1/ TGF-β3 ratio.