Effect of LPS on 7KCh-mediated inflammation.

<p>ARPE19 cells were treated with two concentrations of LPS (20 and 50 µg/ml) for 24 hr and the mRNA inductions of the inflammatory markers measured by qRT-PCR<b>. (a)</b> Measurement (mean ± s.d., <i>n</i> = 3) of the inflammatory in response to LPS. LPS does not induce any inflammatory response in ARPE19 cells. <b>(b)</b> Measurements (mean ± s.d., <i>n</i> = 3) in cells treated with 8 µM 7KCh for 24 hr with and without 50 µg/ml LPS. LPS reduced the mRNA induction of all of the inflammatory markers VEGF (4.6 to 1.4 fold), IL-1β (4.0 to 1.4 fold), IL-6 (33.7 to 3.8 fold), IL-8 (7.2 to 1.4 fold), CHOP (31.0 to 3.7 fold), and GRP78 (7.1 to 1.5 fold). <b>(c)</b> Measurements of secreted cytokines (mean ± s.d.) from conditioned in cells treated with 6 µM 7KCh for 48 hr (VEGF, <i>n</i> = 3) or 8 µM 7KCh for 24 hr (IL-6 and IL-8, <i>n</i> = 4) with and without 50 µg/ml LPS. LPS reduced the levels of VEGF (1035 pg/ml to 848 pg/ml) and IL-6 (191 pg/ml to 77 pg/ml) but had no significant effect on IL-8. <b>(d)</b> Immunoblot demonstrating that LPS pretreatment significantly reduced the 7KCh-induced expression of CHOP and GRP78. *<i>p</i><0.05, two-tailed Student's t-test.