Correlational analysis of the regulatory interplay between molecules and cellular components mediating angiogenesis in wound healing under normal and hyperglycemic conditions.

Abstract

The aim of this study was to correlate the content of cells with regulatory molecules associated with angiogenesis in wound healing in a rat model of hyperglycemia. We hypothesize that blood neutrophils are the main VEGF source and can stimulate FLT-1 receptor expression, which is the perquisite for efficient neoangiogenesis. Kinetic studies of the healing dynamics (3, 7, 14, 21 days) of burn wounds on the skin were conducted in white adult male rats. The content of nuclear factor kappa B (NF-κB), vascular endothelial growth factor (VEGF), its receptor (Flt-1) in the regenerated tissue was analyzed by western blot. Numbers of cells associated with the regenerative process and from peripheral blood (PB) were determined. Additionally a bone marrow (BM) myelogram was conducted. The relative number of peripheral blood (PB) neutrophils was found to be associated with the level of VEGF (R = 0.708) and Flt-1 (R = 0.472). The relative number of fibroblasts was also associated with VEGF (R = 0.562), but not with Flt-1. A negative association was found between the number of neutrophils in the regenerated tissue with VEGF (R = -0.454) and FLT-1 (R = -0.665). This confirms our hypothesis, that blood neutrophils are the main VEGF producer that stimulate the expression of the FLT-1 receptor subsequently inducing neoangiogenesis.Furthermore, that under hyperglycemic conditions fibroblasts were highly associated with VEGF (R = 0.800), while negatively associated with FLT-1 (R = -0.506). There was a high association between PB neutrophils and newly generated tissue cells: neutrophils (R = 0.717) and macrophages (R = 0.622), as well as the association between neutrophils and macrophages (R = 0.798). This is an indication of chronic inflammation and increased transmigration of blood cells to the burned tissue. Blood neutrophils are the main producer of VEGF and stimulate the expression of the FLT-1 receptor. In the context of hyperglycemia the imbalance of receptor and ligand associated with angiogenesis indicates for chronic inflammation: VEGF and FLT-1, which facilitates hypoxia, prevents the physiological course of burn wound healing and may be an important factor in impaired tissue regeneration in diabetes.