Effect of homocysteine on the expression of macrophage inflammatory protein-1α in THP-1 monocytes

AIM: To investigate whether homocysteine (HCY) induce the expression of macrophage inflammatory protein-1α(MIP-1α)in cultured THP-1 monocytes. METHODS: After exposure of THP-1 monocytes to HCY at increasing concentrations (0.05,0.1 and 0.2 mmol/L) for 8 h, or at 0.1 mmol/L of HCY for different incubation times (4, 8 and 16 h), the expressions of MIP-1α mRNA and protein were determined by RT-PCR and immunocytochemistry, respectively. RESULTS: RT-PCR showed that the expression of MIP-1α mRNA increased with the concentrations of HCY compared with the control group. Meanwhile, after the treatment of 0.1 mmol/L HCY to the cells for different times, the MIP-1α mRNA expression increased at 4 h, peaked at 8 h, and then decreased at 16 h. The authenticity of RT-PCR products was confirmed by DNA sequencing. Image analysis of Immunocytochemistry assay showed the expression of MIP-1α protein in experimental groups increased in a dose- and time-dependent manner(P＜0.01). CONCLUSIONS: HCY induced monocytes to express MIP-1α mRNA and protein.