Monocyte chemotactic protein-1 (MCP-1) mRNA is down-regulated in human dermal fibroblasts by dexamethasone: differential regulation by TGF-beta.

Macrophages are a source of cytokines driving repair. Wound macrophages are derived from circulating monocytes. Monocyte chemotactic protein-1 (MCP-1) is a potent specific monocyte chemoattractant. Treatment of serum stimulated dermal fibroblasts with dexamethasone led to a dose dependent down-regulation of MCP-1 mRNA levels. Such an anti-inflammatory effect may partially explain the negative influence of glucocorticoid treatment on wound repair. Topical or parenteral of fibroblasts cultured in serum free media with TGF-beta increased MCP-1 mRNA levels. TGF-beta treatment of fibroblasts cultured in serum also partially overcame the dexamethasone mediated decrease in MCP-1 mRNA levels. In glucocorticoid treated animals TGF-beta may stimulate repair by an indirect pro-inflammatory action following transcriptional up-regulation of MCP-1.