Evaluation effects of chitosan for the extracellular matrix production by fibroblasts and the growth factors production by macrophages

Chitosan is reported as an accelerator of wound healing. Histological findi ngs of previous reports indicate that chitosan accelerates the reformation of connective tissue, however the details of the mechanism are not clear. I n this study, firstly L929 mouse fibroblasts were cultured with chitosan an d the production of extracellular matrix (ECM) was evaluated in vitro. Type I and III collagens and fibronectin were secreted by L929 with or without chitosan; however there was no significant difference in the amount of ECM between the control and the chitosan groups. Secondly, macrophages were sti mulated with chitosan, and then transforming growth factor-beta 1 (TGF-beta 1) and platelet-derived growth factor (PDGF) messenger ribonucleic acid (mR NA) expressions and production of their proteins were assayed in vitro. As a result, chitosan promoted the production of TGF-beta1 and PDGF. These res ults indicate that chitosan does not directly accelerate ECM production by fibroblast and the ECM production may increase by the growth factors. (C) 2 001 Elsevier Science Ltd. All rights reserved.