C. difficile infection (CDI)-induced activation of p38, JNK, and ERK. Cecal tissues from noninfected and C. difficile-infected C57/BL6 mice were homogenized, and supernatants were used for analysis of phosphorylated (p-) and total p38, JNK, and ERK by Western blot analysis. β-Actin served as a loading control. Asterisks indicate significant differences (*, P < 0.01) from results for noninfected mice.