Figure 7
MMP-7 induces Fas ligand expression in renal interstitial fibroblasts and potentiates fibroblast apoptosis.
(a, b) Recombinant MMP-7 induced Fas ligand (FasL) expression in a time- and dose-dependent manner. Normal rat kidney interstitial fibroblast (NRK-49F) cells were incubated with 50 nM of MMP-7 for various periods of time (a), or different doses of MMP-7 for 24 h (b). Cell lysates were immunoblotted with antibodies against FasL, Bax and actin, respectively. (c) MMP-7 alone did not significantly induce fibroblast apoptosis. (d through g) MMP-7 potentiated fibroblast apoptosis induced by staurosporine (STS). NRK-49F cells were incubated with different doses of MMP-7 for 24 h (d, e) or 50 nM of MMP-7 for various periods of time (f, g) in the presence of 0.1 μM staurosporine. Representative micrographs (d, f) and quantitative data (e, g) are presented. (h, i) MMP-7 promoted Bax induction in renal interstitial fibroblasts. NRK-49F cells were incubated with 50 nM of MMP-7 for various periods of time (h) or different doses of MMP-7 for 24 h (i) in the presence of 0.1 μM staurosporine. Cell lysates were immunoblotted with antibodies against Bax and actin, respectively.
