The effect of estrogen on diabetic wound healing is mediated through increasing the function of various bone marrow-derived progenitor cells.

Abstract

OBJECTIVE:

Endothelial progenitor cells (EPCs) are the key cells of postnatal neovascularization, and mesenchymal stem cells (MSCs) possess pluripotent differentiation capacity and contribute to tissue regeneration and wound healing. Both EPCs and MSCs are critical to the wound repair process, which is hindered in diabetes mellitus. Diabetes has been shown to decrease the function of these progenitor cells, whereas estrogen has beneficial wound healing effects. However, the role of estrogen in modulating EPC and MSC biology in diabetes is unknown. We investigated the effect of estrogen on improving bone marrow (BM)-derived EPC and MSC function using a murine diabetic wound healing model.

METHODS:

Female diabetic db+/db+ and nondiabetic control mice were wounded cutaneously and treated with topical estrogen or placebo cream. On day 5 after wounding, BM cells were harvested to quantify EPC number and colony-forming units of EPCs and MSCs. Wound healing rate was concurrently studied. Vessel density and scar density were then quantified using whole body perfusion and laser confocal microscopy. EPC recruitment was documented by immunohistochemistry to identify CD34- and vascular endothelial growth factor receptor 2-positive cells in the vessel wall. Data were analyzed by analysis of variance.

RESULTS:

Topical estrogen significantly increased colony-forming units of both EPCs and MSCs compared with placebo treatment, indicating improved viability and proliferative ability of these cells. Consistently, increased recruitment of EPCs to diabetic wounds and higher vessel density were observed in estrogen-treated compared with placebo-treated mice. Consequently, topical estrogen significantly accelerated wound healing as early as day 6 after wounding. In addition, scar density resulting from collagen deposition was increased in the estrogen-treated group, reflecting increased MSC activity and differentiation.

CONCLUSIONS:

Estrogen treatment increases wound healing and wound neovascularization in diabetic mice. Our data implicate that these beneficial effects may be mediated through improving the function of BM-derived EPCs and MSCs.

• Authors: Ying Zhuge, Manuela M Regueiro, Runxia Tian, Yan Li, Xiaomei Xia, Roberto Vazquez-Padron, Sharon Elliot, Seth R Thaller, Zhao-Jun Liu, Omaida C Velazquez
• Journal: Journal of vascular surgery (J Vasc Surg) Vol. 68 Issue 6S Pg. 127S-135S (12 2018) ISSN: 1097-6809 [Electronic] United States
• PMID: 30064832 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Chemical References

• Antigens, CD34
• Estrogens
• Ointments
• Collagen
• Kdr protein, mouse
• Vascular Endothelial Growth Factor Receptor-2

Topics

• Administration, Cutaneous
• Animals
• Antigens, CD34 (metabolism)
• Cell Proliferation (drug effects)
• Collagen (metabolism)
• Diabetes Mellitus (metabolism, pathology)
• Endothelial Progenitor Cells (drug effects, metabolism, pathology)
• Estrogens (administration & dosage)
• Female
• Mesenchymal Stem Cells (drug effects, metabolism, pathology)
• Mice, Mutant Strains
• Neovascularization, Physiologic (drug effects)
• Ointments
• Phenotype
• Skin (blood supply, drug effects, injuries, metabolism)
• Time Factors
• Vascular Endothelial Growth Factor Receptor-2 (metabolism)
• Wound Healing (drug effects)
• Wounds, Penetrating (drug therapy, metabolism, pathology)