25(OH)D3 and 1.25(OH)2D3 inhibits TNF-α expression in human monocyte derived macrophages

Purpose We wanted to investigate effects of vitamin D-3 (25(OH)D-3 and 1.25(OH)(2)D-3) on inflammatory cytokine expression in both activated and non-activated M phi. Materials and methods Mononuclear cells, isolated from healthy donor buffy coats were cultured for a 6-day differentiation-period. Fully differentiated M phi were pre-treated with either 25(OH)D-3 or 1.25(OH)(2)D-3 for (4, 12 or 24 hours) +/-LPS challenge for 4 hours. Gene expression analyses of VDR, Cyp27b1 and pro-inflammatory markers TNF-alpha, IL-6, NF-kappa B, MCP-1, was performed using RT-quantitative PCR. TNF-alpha protein levels from M phi culture media were analysed by ELISA. Results Both 25(OH)D-3 and 1.25(OH)(2)D-3 significantly inhibited TNF-alpha expression in both LPS-stimulated and unstimulated M phi. Also, NF-kappa B, and to a lesser extend IL-6 and MCP-1 were inhibited. LPS up-regulated Cyp27b1 gene expression which was partly reverted by 1.25 (OH)(2)D-3. Conclusion These data show anti-inflammatory effects of vitamin D-3 (25(OH)D-3 and 1.25(OH)(2)D-3) in human macrophages, and support, that means for targeting high dose vitamin D3 to the immune system may have beneficial clinical effect in inflammatory conditions.