Figure 6
Mevalonate cascade inhibition changes the balance and localization of anti and proapoptotic Bcl-2 family member and affects mitochondrial membrane potential in myocardial atrial fibroblast. (a and b) Myocardial atrial fibroblasts were treated with simvastatin (10 μM) for indicated times and pro and antiapoptotic Bcl-2 family member expression and localization (cytosolic/mitochondria-enriched fraction) were investigated using immunoblotting. Mevalonate cascade inhibition increased proapoptotic Bcl-2 family member expression and their mitochondrial localization while also decreasing antiapoptotic Bcl-2 family members and their mitochondrial localization. (c) Simvastatin decreased mitochondrial membrane potential in treated myocardial atrial fibroblast. Cells were treated with simvastatin (10 μM, 72 h) and mitochondrial membrane potential were measured using JC-1 (***P<0.001) (see Materials and Methods section for details). (d–f) Mevalonate cascade inhibition decreased Bcl-2 expression via SAPK/JNK activation in myocardial atrial fibroblast. Cells were treated with simvastatin (10 μM) for indicated time points. Simvastatin increased SAPK/JNK phosphorylation (d) and (e) SAPK/JNK inhibitor (SB600123, 150 nM) significantly (**P<0.01) enhanced cell viability in the presence of simvastatin (10 μM, 72 h). Cells were pretreated with indicated concentration of SB600123 for 4 h and then co-treated with indicated concentration of simvastatin. Cell viability was measured using MTT assay. (f) SAPK/JNK inhibitor (SB600123, 150 nM) also inhibited the effect of simvastatin (10 μM, 72 h) on Bcl-2 expression
