Figure 1.

Rapamycin reduced mesangial cell proliferation and inhibited p70S6K phosphorylation. (a) MTT assay for cell proliferation; the optical density (OD) was measured at 492 nm. (b) The rate of inhibition of MC proliferation by rapamycin. Rapamycin inhibited cell proliferation induced by PDGF-BB in dose- and time-dependent manners at 24 and 48 h. Rapamycin treatment at 1 nmol/L for 48 h but not for 24 h significantly suppressed MC proliferation. There was no significant difference between the groups using 100 or 1000 nmol/L (n = 6/group). (c) Flow cytometry for cell apoptosis. Rapamycin had no obvious effect on apoptosis of MCs and there was no abundance of dead cells at 1000 nmol/L group. (d) Rapamycin (10–1000 nmol/L) significantly inhibited p70S6K phosphorylation by blocking the phosphorylation of mTOR in a dose-dependent manner . However, the test results for p70S6k mRNA showed that rapamycin does not affect its expression (Figure 1d)’.

The data are presented as the mean ± SD.

*P < 0.05. **P < 0.01 versus control.

^#P < 0.05. ^##P < 0.01 versus PDGF.