Effect of homocysteine on expression of interleukin-8 mRNA and protein in THP-1 macrophages

AIM: To investigate the effect of homocysteine (Hcy) on expression of interleukin-8 (IL-8) mRNA and protein in THP-1-derived macrophages (THP-1 macrophages). METHODS: Cultured THP-1 monocytes were induced to macrophages by 0 1 μmol/L PMA treatment for 72 hours, then the differentiated THP-1 macrophages were incubated with homocysteine (0 01 mmol/L-0 20 mmol/L) for 24 hours, or with 0 10 mmol/L Hcy for various time up to 48 hours. IL-8 protein in THP-1 supernatants was measured by ELISA, and IL-8 mRNA expression was detected by semiquantitive RT-PCR. RESULTS: Compared with control, Hcy significantly increased the expression of IL-8 protein in a concentration-dependent manner. 0 05 mmol/L, 0 10 mmol/L and 0 20 mmol/L Hcy increased IL-8 production by 1 28 fold, 1 32 fold and 1 55 fold, respectively ( P0 01 ). IL-8 production were elevated significantly 3 h after treatment with 0 10 mmol/L Hcy. In addition, Hcy also increased IL-8 mRNA expression in a concentration-and time-dependent manner. CONCLUSION: Hcy may contribute to atherogenesis by inducing IL-8 expression and secretion in THP-1 macrophages. [