Figure 6.

Effect of an AGE-modified type I collagen substratum on the generation of intracellular reactive oxygen species by MC3T3E1 and UMR106 cells. Osteoblasts were cultured at 37°C either on control collagen or on AGE-modified collagen. After 48 hours, media were replaced by phenol red-free DMEM with 10 μM dihydro-rhodamine, and cells were incubated for an additional 4 hours. At the end of this incubation the cell monolayers were lysated with 0.1 % Triton X-100, and the levels of the oxidation product rhodamine were measured in the lysates by the determination of fluorescence intensity (excitation wavelength 495 nm, emission wavelength 532 nm). Results are given as a percentage of the corresponding basal condition (unmodified collagen), and are expressed as the mean ± SEM. Differences between collagen vs. AGE-collagen are as follows: * p<0.01; ** p<0.001