High glucose-induced growth factor resistance in human fibroblasts can be reversed by antioxidants and protein kinase C-inhibitors

We have studied the influence of high glucose on basal fibroblast proliferation, growth factor induced cellular proliferation and the effects of antioxidants, protein kinase C-inhibitors and troglitazone. Fibroblast cultures were obtained from five patients undergoing mammary reduction plastic surgery. A fluorometric method was used for determining total DNA in the cell samples, DNA content being proportional to cell number. D-Glucose at 15.5 mM and above was shown to inhibit fibroblast proliferation, and the cells were resistant to growth factors such as IGF-I and EGF at this glucose concentration. H7, bisindolylmaleimide IX, troglitazone, alpha-tocopherol acetate, Q10, ascorbic acid, beta-carotene, DMTU and selenite were all found to reverse the high glucose-induced growth factor resistance observed in human fibroblasts. We believe that these findings may be of value in the understanding and future treatment of wound healing in diabetic foot ulcers.