Fig. 2

Effect of H. pylori infection and coinfection on activity and expression of MMPs. Different strains of H. pylori (AM1 or SS1) were orally fed separately or coinfected (AM1/SS1or SS1/AM1) to four groups of mice and they were sacrificed on day 10 post infection. Control mice were fed with PBS and kept separately under same conditions. The activities of MMP2 and 9 in mouse gastric tissue extracts were measured by gelatin zymography (a). Histographic representations of gelatinolytic activities as measured by lab image densitometry (b). Values were from the above zymograms and three other zymograms from independent experiments. Expression of MMP9 was measured by Western blotting analysis (c). Equal amount of tissue extracts (120 μg) of control and infected mice were used and probed with polyclonal anti-MMP9 and monoclonal anti-β actin antibody. The activity and expression of MMP3 in mouse gastric tissue extracts were measured by casein zymography and Western blot. Representative blots showing the activity and expression MMP3 (d, f). β-actin served as loading control. Histographic representations of MMP3 activity and expressions in control and H. pylori infected gastric tissues (e) from the above blots and two other representative blots from independent experiments in each case. Error bars ±SEM ***P < 0.001; **P < 0.01; *P < 0.05; NS, P = not significant versus control