Figure 7.

Western blots of confluent rat L2 cells, treated with PBS (Cont), HMW-HA (200 ng/mL) for 24 h, S1 (100 ng) for 24 h or HMW-HA for 1 h followed by S1 for 24 h. A: immunoblotting was performed using specific antibodies against E2F1, its phosphorylated form and actin (top). The intensities of the shown bands were quantified and the ratios of pE2F1 to E2F1 are shown at bottom. B and C: immunoblotting was performed using specific antibodies against phosphRhoA (active RhoA), total RhoA, phosphoROCK2, or total ROCK2 (top). The intensities of the various bands were quantified and the ratios of the phosphorylated to total forms are shown (bottom). Incubation of rat L2 cells with S1 upregulated the activities of the phosphorylated forms of E2F1, RhoA, and its downstream kinase, ROCK2. Preincubation with HMW-HA prevented these effects. Values are means with standard error of the means and individual points from three different batches of cells. One-way analysis of variance followed by the Tukey’s t test for multiple comparisons. HA, hyaluronan (hyaluronic acid); HMW, high molecular weight.