Effect of LDL-Ox on genes related to inflammatory process in macrophage cells

GONZALEZ MC; LEDDA A; GRASSA MM; MANSILLA L; TOLEDO JD; GARDA HA; ESTEVE RAFOLS M

Puerto Varas

Congreso; XII Congress of Panamerican Association for Biochemistry and Molecular Biology; 2013

Panamerican Association for Biochemistry and Molecular Biology (PABMB)

Isolated LDL fraction from human plasma was peroxidized in vitro with Cu++. THP1 human cells (as monocytes and macrophages) were treated with LDL-Ox for 4, 8, 12 and 24 h. Monocytes were transformed into macrophages by adding PMA in the culture medium. We evaluated the expression of genes involved in the inflammatory (TNFα, FAT/CD36) and anti inflammatory process (11ßHSD1, MMR). The mRNA level of different genes was measured by quantitative real-time PCR. In THP1-monocytes, FAT/CD36 and ACAT1 gene expression related to LDL-Ox incorporation, fatty acid esterification and formation of foam cells increased at 8 h; however, THP1-macrophages needed longer time (24 h LDL-Ox treatment) to show the increment. Results showed, again, an increase of pro-inflammatory marker TNFα at short time incubation in THP1-monocytes and longer time in THP-1 macrophages. The 11ßHSD1 expression indicates the reduction of cortisona to cortisol (glucocorticoid active form). In THP1-monocytes, the effect of LDL-Ox promotes a significant increase of 11ßHSD1 expression at all the times tested; however, in THP1-macrophages the increment was only at short times. The increase of the gene F4/80 (macrophages marker) and the decrease of MMR (antiinflammatory macrophages marker) suggest that longer LDL exposition times promoted the proliferation of pro-inflammatory macrophages population. In conclusion, monocytes showed a more rapid pro-inflammatory response than macrophages type.